Is Atherectomy the Best First-Line Therapy for Limb Salvage in Patients With Critical Limb Ischemia?

PubMed Central

Loor, Gabriel; Skelly, Christopher L.; Wahlgren, Carl-Magnus; Bassiouny, Hisham S.; Piano, Giancarlo; Shaalan, Wael

2010-01-01

Objective To determine the efficacy of atherectomy for limb salvage compared with open bypass in patients with critical limb ischemia. Methods Ninety-nine consecutive bypass and atherectomy procedures performed for critical limb ischemia between January 2003 and October 2006 were reviewed. Results A total of 99 cases involving TASC C (n = 43, 44%) and D (n = 56, 56%) lesions were treated with surgical bypass in 59 patients and atherectomy in 33 patients. Bypass and atherectomy achieved similar 1-year primary patency (64% vs 63%; P = .2). However, the 1-year limb salvage rate was greater in the bypass group (87% vs 69%; P = .004). In the tissue loss subgroup, there was a greater limb salvage rate for bypass patients versus atherectomy (79% vs 60%; P = .04). Conclusions Patients with critical limb ischemia may do better with open bypass compared with atherectomy as first-line therapy for limb salvage. PMID:19640919

Functional specialisation of pelvic limb anatomy in horses (Equus caballus)

PubMed Central

Payne, RC; Hutchinson, JR; Robilliard, JJ; Smith, NC; Wilson, AM

2005-01-01

We provide quantitative anatomical data on the muscle–tendon units of the equine pelvic limb. Specifically, we recorded muscle mass, fascicle length, pennation angle, tendon mass and tendon rest length. Physiological cross sectional area was then determined and maximum isometric force estimated. There was proximal-to-distal reduction in muscle volume and fascicle length. Proximal limb tendons were few and, where present, were relatively short. By contrast, distal limb tendons were numerous and long in comparison to mean muscle fascicle length, increasing potential for elastic energy storage. When compared with published data on thoracic limb muscles, proximal pelvic limb muscles were larger in volume and had shorter fascicles. Distal limb muscle architecture was similar in thoracic and pelvic limbs with the exception of flexor digitorum lateralis (lateral head of the deep digital flexor), the architecture of which was similar to that of the pelvic and thoracic limb superficial digital flexors, suggesting a functional similarity. PMID:15960766

Developmental origin of limb size variation in lizards.

PubMed

Andrews, Robin M; Skewes, Sable A

2017-05-01

In many respects, reptile hatchlings are fully functional, albeit miniature, adults. This means that the adult morphology must emerge during embryonic development. This insight emphasizes the connection between the mechanisms that generate phenotypic variation during embryonic development and the action of selection on post-hatching individuals. To determine when species-specific differences in limb and tail lengths emerge during embryonic development, we compared allometric patterns of early limb growth of four distantly related species of lizards. The major questions addressed were whether early embryonic limb and tail growth is characterized by the gradual (continuous allometry) or by the abrupt emergence (transpositional allometry) of size differences among species. Our observations supported transpositional allometry of both limbs and tails. Species-specific differences in limb and tail length were exhibited when limb and tail buds first protruded from the body wall. Genes known to be associated with early limb development of tetrapods are obvious targets for studies on the genetic mechanisms that determine interspecific differences in relative limb length. Broadly comparative studies of gene regulation would facilitate understanding of the mechanisms underlying adaptive variation in limb size, including limb reduction and loss, of squamate reptiles. © 2017 Wiley Periodicals, Inc.

An attempt to detect lameness in galloping horses by use of body-mounted inertial sensors.

PubMed

Lopes, Marco A F; Dearo, Antonio C O; Lee, Allen; Reed, Shannon K; Kramer, Joanne; Pai, P Frank; Yonezawa, Yoshiharu; Maki, Hiromitchi; Morgan, Terry L; Wilson, David A; Keegan, Kevin G

2016-10-01

OBJECTIVE To evaluate head, pelvic, and limb movement to detect lameness in galloping horses. ANIMALS 12 Thoroughbreds. PROCEDURES Movement data were collected with inertial sensors mounted on the head, pelvis, and limbs of horses trotting and galloping in a straight line before and after induction of forelimb and hind limb lameness by use of sole pressure. Successful induction of lameness was determined by measurement of asymmetric vertical head and pelvic movement during trotting. Differences in gallop strides before and after induction of lameness were evaluated with paired-sample statistical analysis and neural network training and testing. Variables included maximum, minimum, range, and time indices of vertical head and pelvic acceleration, head rotation in the sagittal plane, pelvic rotation in the frontal plane, limb contact intervals, stride durations, and limb lead preference. Difference between median standardized gallop strides for each limb lead before and after induction of lameness was calculated as the sum of squared differences at each time index and assessed with a 2-way ANOVA. RESULTS Head and pelvic acceleration and rotation, limb timing, stride duration measurements, and limb lead preference during galloping were not significantly different before and after induction of lameness in the forelimb or hind limb. Differences between limb leads before induction of lameness were similar to or greater than differences within limb leads before and after lameness induction. CONCLUSIONS AND CLINICAL RELEVANCE Galloping horses maintained asymmetry of head, pelvic, and limb motion between limb leads that was unrelated to lameness.

Does a balance deficit persist in Australian Football players with previous lower limb ligament injury?

PubMed

Hrysomallis, C; McLaughlin, P; Goodman, C

2005-03-01

A history of lower limb ligament injury is a commonly-cited risk factor for another similar injury. During the acute phase of injury, there is a balancing skill deficit in the injured limb. It has been unclear as to whether this deficit persists in the medium-to-long term for previously injured Australian footballers, contributing to the risk of re-injury. This study compared the balance ability of footballers with and without previous lower limb ligament injury and, for previously injured players, the balance ability of the previously injured limb to the opposite uninjured limb. A total of 216 players from 6 teams from the Australian Football League were tested. The balance task comprised stepping on to a foam mat on top of a force plate and maintaining one-legged balance. The subjects were divided into 4 groups based on their injury history: all ankle injuries to only one limb, recent ankle injuries to only one limb (within the last 12 months), knee ligament injury only to one limb, and no previous ankle or knee ligament injury. Statistical analysis revealed that there was no significant difference between the balance scores of any of the previously injured players and those with no previous lower limb ligament injury. There was no significant difference between the balance score of the previously injured limb with the opposite uninjured limb. It appears that a balance deficit does not persist in Australian Football players with previous lower limb ligament injury.

Long-term outcome of dogs treated with ulnar rollover transposition for limb-sparing of distal radial osteosarcoma: 27 limbs in 26 dogs.

PubMed

Séguin, Bernard; O'Donnell, Matthew D; Walsh, Peter J; Selmic, Laura E

2017-10-01

To determine outcomes in dogs with distal radial osteosarcoma treated with ulnar rollover transposition (URT) limb-sparing surgery including: viability of the ulnar graft, complications, subjective limb function, disease-free interval (DFI), and survival time (ST). Retrospective case series. Twenty-six client-owned dogs with distal radial osteosarcoma and no involvement of the ulna. Data of dogs treated with URT were collected at the time of surgery and retrospectively from medical records and by contacting owners and referring veterinarians. URT technique was performed on 27 limbs in 26 dogs. The ulnar graft was determined to be viable in 17 limbs, nonviable in 3, and unknown in 7. Complications occurred in 20 limbs. Infection was diagnosed in 12 limbs. Biomechanical complications occurred in 15 and local recurrence in 2 limbs. Limb function graded by veterinarians or owners was poor in 2 limbs, fair in 4, good in 14, excellent in 3, and unknown in 4. Median DFI was 245 days and median ST was 277 days. The URT technique maintained the viability of the ulnar graft. The complication rate was high but limb function appeared acceptable. Although sufficient length of the distal aspect of the ulna must be preserved to perform this technique, local recurrence was not increased compared to other limb-sparing techniques when cases were appropriately selected. © 2017 The American College of Veterinary Surgeons.

Trunk and Shank Position Influences Patellofemoral Joint Stress in the Lead and Trail Limbs During the Forward Lunge Exercise.

PubMed

Hofmann, Cory L; Holyoak, Derek T; Juris, Paul M

2017-01-01

Study Design Controlled laboratory study, repeated-measures design. Background The effects of trunk and shank position on patellofemoral joint stress of the lead limb have been well studied; however, the effects on the trail limb are not well understood. Objectives To test the hypothesis that trunk and shank position may influence patellofemoral joint stress in both limbs during the forward lunge exercise. Methods Patellofemoral kinetics were quantified from 18 healthy participants performing the lunge exercise with different combinations of trunk and shank positions (vertical or forward). A 2-by-3 (limb-by-lunge variation) repeated-measures analysis of variance was performed, using paired t tests for post hoc comparisons. Results The trail limb experienced greater total patellofemoral joint stress relative to the lead limb, regardless of trunk and shank position (P<.0001). The lunge variation with a vertical shank position resulted in significantly greater peak patellofemoral joint stress in the trail limb relative to the lead limb (P<.0001). A forward trunk and shank position resulted in the highest patellofemoral stress in the lead limb (P<.0001). Conclusion Trunk and shank positions have a significant influence on patellofemoral joint loading of both limbs during the forward lunge, with the trail limb generally experiencing greater total joint stress. Restricting forward translation of the lead-limb shank may reduce patellofemoral joint stress at the expense of increased stress in the trail limb. Technique recommendations should consider the demands imposed on both knees during this exercise. J Orthop Sports Phys Ther 2017;47(1):31-40. Epub 4 Nov 2016. doi:10.2519/jospt.2017.6336.

Gait termination on a declined surface in trans-femoral amputees: Impact of using microprocessor-controlled limb system.

PubMed

Abdulhasan, Zahraa M; Scally, Andy J; Buckley, John G

2018-05-30

Walking down ramps is a demanding task for transfemoral-amputees and terminating gait on ramps is even more challenging because of the requirement to maintain a stable limb so that it can do the necessary negative mechanical work on the centre-of-mass in order to arrest (dissipate) forward/downward velocity. We determined how the use of a microprocessor-controlled limb system (simultaneous control over hydraulic resistances at ankle and knee) affected the negative mechanical work done by each limb when transfemoral-amputees terminated gait during ramp descent. Eight transfemoral-amputees completed planned gait terminations (stopping on prosthesis) on a 5-degree ramp from slow and customary walking speeds, with the limb's microprocessor active or inactive. When active the limb operated in its 'ramp-descent' mode and when inactive the knee and ankle devices functioned at constant default levels. Negative limb work, determined as the integral of the negative mechanical (external) limb power during the braking phase, was compared across speeds and microprocessor conditions. Negative work done by each limb increased with speed (p < 0.001), and on the prosthetic limb it was greater when the microprocessor was active compared to inactive (p = 0.004). There was no change in work done across microprocessor conditions on the intact limb (p = 0.35). Greater involvement of the prosthetic limb when the limb system was active indicates its ramp-descent mode effectively altered the hydraulic resistances at the ankle and knee. Findings highlight participants became more assured using their prosthetic limb to arrest centre-of-mass velocity. Copyright © 2018 Elsevier Ltd. All rights reserved.

Surgical Tourniquets in Orthopaedics

DTIC Science & Technology

2009-12-01

occlusion pressure and the ratio of the cuff width to the limb circumference23. This relationship is shown in Figure 4, indicating that, for a given limb...measured limb occlusion pressure to account for physiologic Fig. 3 a: A normal node of Ranvier of a nerve in a limb, showing a nodal gap 1 to 2 mm in ...limb occlusion pressure an additional pressure safety margin that is selected to be greater than the magnitude of any increase in limb occlusion

Energetic benefits and adaptations in mammalian limbs: Scale effects and selective pressures.

PubMed

Kilbourne, Brandon M; Hoffman, Louwrens C

2015-06-01

Differences in limb size and shape are fundamental to mammalian morphological diversity; however, their relevance to locomotor costs has long been subject to debate. In particular, it remains unknown if scale effects in whole limb morphology could partially underlie decreasing mass-specific locomotor costs with increasing limb length. Whole fore- and hindlimb inertial properties reflecting limb size and shape-moment of inertia (MOI), mass, mass distribution, and natural frequency-were regressed against limb length for 44 species of quadrupedal mammals. Limb mass, MOI, and center of mass position are negatively allometric, having a strong potential for lowering mass-specific locomotor costs in large terrestrial mammals. Negative allometry of limb MOI results in a 40% reduction in MOI relative to isometry's prediction for our largest sampled taxa. However, fitting regression residuals to adaptive diversification models reveals that codiversification of limb mass, limb length, and body mass likely results from selection for differing locomotor modes of running, climbing, digging, and swimming. The observed allometric scaling does not result from selection for energetically beneficial whole limb morphology with increasing size. Instead, our data suggest that it is a consequence of differing morphological adaptations and body size distributions among quadrupedal mammals, highlighting the role of differing limb functions in mammalian evolution. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

Gender differences in asymmetrical limb support patterns between subjects with and without recurrent low back pain.

PubMed

Sung, Paul S; Zipple, J Tim; Danial, Pamela

2017-04-01

New insight regarding limb-dominance effects on temporal-spatial gait parameters is needed to further investigate subjects with recurrent low back pain (LBP). Although an asymmetrical gait pattern was found to reflect natural functional differences, there is a lack of information regarding gender differences on dominant limb support patterns in subjects with LBP. The purpose of this study was to investigate temporal-spatial gait parameters based on limb dominance and gender between subjects with and without LBP. One hundred and ten right limb dominant older adults (51 subjects with LBP and 59 control subjects) participated in the study. A three-dimensional motion capture system was utilized to measure temporal-spatial gait parameters, including initial double, single, and terminal double limb support times and walking speed. The gender differences between subjects with and without LBP were analyzed based on dominance for those parameters. Overall, limb dominance demonstrated significant differences on single and terminal double limb support times as well as walking speed. Limb dominance also demonstrated interactions on group x gender for single limb support time and walking speed. The male subjects with LBP demonstrated significantly increased single limb support times on the non-dominant limb. The significant gender and group interactions based on limb dominance account for a possible pain avoidance, asymmetrical limb support pattern. The causal pathway in dominance dependency gait by unweighted ambulation might be considered as an intervention for correcting these gait deviations in subjects with LBP. The specific modification recovery profiles of the subjects with LBP could shed light on variability of current LBP experiences of the subjects and reasons for gait deviations. Clinicians need to consider the mechanism of dominant limb dependency, which requires postural control strategies in male subjects with recurrent LBP. Copyright © 2017 Elsevier B.V. All rights reserved.

Customization of biliopancreatic limb length to modulate and sustain antidiabetic effect of gastric bypass surgery.

PubMed

Pal, A; Rhoads, D B; Tavakkoli, A

2018-02-01

Although Roux-en-Y Gastric Bypass (RYGB) remains the most effective treatment for obesity and type 2 diabetes (T2D), many patients fail to achieve remission, or relapse. Increasing intestinal limb lengths of RYGB may improve outcomes, but the mechanistic basis for this remains unclear. We hypothesize biliopancreatic (BP) limb length modulates the antidiabetic effect of RYGB. Rats underwent RYGB with a 20-cm (RYGB-20cm) or 40-cm (RYGB-40cm) BP limb and were compared with control animals. After 2 and 4 wk, portal and systemic blood was sampled during intestinal glucose infusion. Portosystemic gradient was used to calculate intestinal glucose utilization (G util ), absorption (G absorp ), and hormone secretion. Intestinal morphology and gene expression were assessed. At 2 wk, G absorp progressively decreased with increasing BP limb length; this pattern persisted at 4 wk. G util increased ≈70% in both RYGB-20cm and -40cm groups at 2 wk. At 4 wk, G util progressively increased with limb length. Furthermore, Roux limb weight, and expression of hexokinase and preproglucagon, exhibited a similar progressive increase. At 4 wk, glucagon-like peptide-1 and -2 levels were higher after RYGB-40cm, with associated increased secretion. We conclude that BP limb length modulates multiple antidiabetic mechanisms, analogous to the dose-response relationship of a drug. Early postoperatively, a longer BP limb reduces G absorp . Later, G util , Roux limb hypertrophy, hormone secretion, and hormone levels are increased with longer BP limb. Sustained high incretin levels may prevent weight regain and T2D relapse. These data provide the basis for customizing BP limb length according to patient characteristics and desired metabolic effect. NEW & NOTEWORTHY Biliopancreatic limb length in gastric bypass modulates multiple antidiabetic mechanisms, analogous to the dose-response relationship of a drug. With a longer biliopancreatic limb, Roux limb hypertrophy, increased glucose utilization, reduced glucose absorption, and sustained high incretin levels may prevent weight regain and diabetes relapse.

Apparatus for determining changes in limb volume

NASA Technical Reports Server (NTRS)

Bhagat, P. K.; Wu, V. C. (Inventor)

1981-01-01

Measuring apparatus for determining changes in the volume of limbs or other boty extremities by determining the cross-sectional area of such limbs many comprise a transmitter including first and second transducers for positioning on the surface of the limb at a predetermined distance there between, and a receiver including a receiver crystal for positioning on the surface of the limb. The distance between the receiver crystal and the first and second transducers are represented by respective first and second chords of the cross-section of the limb and the predetermined distance between the first and second transducers is represented by a third chord of the limb cross section.

The Floating Upper Limb: Multiple Injuries Involving Ipsilateral, Proximal, Humeral, Supracondylar, and Distal Radial Limb

PubMed Central

Manaan, Qazi; Bashir, Adil; Zahoor, Adnan; Mokhdomi, Taseem A.

2016-01-01

Floating arm injury represents a common yet complicated injury of the childhood severely associated with limb deformation and even morbidity, if not precisely addressed and credibly operated. Here, we report a rare floating upper limb case of a 9-year-old boy with multiple injuries of ipsilateral proximal humeral, supracondylar and distal radial limb. This is the first report to document such a combined floating elbow and floating arm injury in the same limb. In this report, we discuss the surgical procedures used and recovery of the patient monitored to ascertain the effectiveness of the method in limb reorganisation. PMID:27583121

The Floating Upper Limb: Multiple Injuries Involving Ipsilateral, Proximal, Humeral, Supracondylar, and Distal Radial Limb.

PubMed

Manaan, Qazi; Bashir, Adil; Zahoor, Adnan; Mokhdomi, Taseem A; Danish, Qazi

2016-09-01

Floating arm injury represents a common yet complicated injury of the childhood severely associated with limb deformation and even morbidity, if not precisely addressed and credibly operated. Here, we report a rare floating upper limb case of a 9-year-old boy with multiple injuries of ipsilateral proximal humeral, supracondylar and distal radial limb. This is the first report to document such a combined floating elbow and floating arm injury in the same limb. In this report, we discuss the surgical procedures used and recovery of the patient monitored to ascertain the effectiveness of the method in limb reorganisation.

Suppression of morphogenesis in embryonic mouse limbs exposed in vitro to excess gravity

NASA Technical Reports Server (NTRS)

Duke, Jackie C.

1983-01-01

The effect of excess gravity on in vitro mammalian limb chondrogenesis is studied. Limb buds from mice of various gestational stages were exposed to excess gravity (2.6G) using a culture centrifuge. Both forelimbs and hind limbs were cultured, and the development of various limb elements was scored after four to six days. The 2.6G force significantly depressed the development of limb elements when applied during the teratogen-sensitive period of chondrogenesis.

Limb length inequality: clinical implications for assessment and intervention.

PubMed

Brady, Rebecca J; Dean, John B; Skinner, T Marc; Gross, Michael T

2003-05-01

The purpose of this paper is to review relevant literature concerning limb length inequalities in adults and to make recommendations for assessment and intervention based on the literature and our own clinical experience. Literature searches were conducted in the MEDLINE, PubMed, and CINAHL databases. Limb length inequality and common classification criteria are defined and etiological factors are presented. Common methods of detecting limb length inequality include direct (tape measure methods), indirect (pelvic leveling), and radiological techniques. Interventions include shoe inserts or external shoe lift therapy for mild cases. Surgery may be appropriate in severe cases. Little agreement exists regarding the prevalence of limb length inequality, the degree of limb length inequality that is considered clinically significant, and the reliability and validity of assessment methods. Based on correlational studies, the relationship between limb length inequality and orthopaedic pathologies is questionable. Stronger support for the link between low back pain (LBP) and limb length inequality is provided by intervention studies. Methods involving palpation of pelvic landmarks with block correction have the most support for clinical assessment of limb length inequality. Standing radiographs are suggested when clinical assessment methods are unsatisfactory. Clinicians should exercise caution when undertaking intervention strategies for limb length inequality of less than 5 mm when limb length inequality has been identified with clinical techniques. Recommendations are provided regarding intervention strategies.

Electromyographic analysis of trunk and hip muscles during resisted lateral band walking.

PubMed

Youdas, James W; Foley, Brooke M; Kruger, BreAnna L; Mangus, Jessica M; Tortorelli, Alis M; Madson, Timothy J; Hollman, John H

2013-02-01

The purpose of this study was to simultaneously quantify bilateral activation/recruitment levels (% maximum voluntary isometric contraction [MVIC]) for trunk and hip musculature on both moving and stance lower limbs during resisted lateral band walking. Differential electromyographic (EMG) activity was recorded in neutral, internal, and external hip rotation in 21 healthy participants. EMG signals were collected with DE-3.1 double-differential surface electrodes at a sampling frequency of 1,000 Hz during three consecutive lateral steps. Gluteus medius average EMG activation was greater (p = 0.001) for the stance limb (52 SD 18% MVIC) than moving limb (35 SD 16% MVIC). Gluteus maximus EMG activation was greater (p = 0.002) for the stance limb (19 SD 13% MVIC) than moving limb (13 SD 9% MVIC). Erector spinae activation was greater (p = 0.007) in hip internal rotation (30 SD 13% MVIC) than neutral rotation (26 SD 10% MVIC) and the moving limb (31 SD 15% MVIC) was greater (p = 0.039) than the stance limb (23 SD 11% MVIC). Gluteus medius and maximus muscle activation were greater on the stance limb than moving limb during resisted lateral band walking. Therefore, clinicians may wish to consider using the involved limb as the stance limb during resisted lateral band walking exercise.

Society for Vascular Surgery Wound, Ischemia, foot Infection (WIfI) score correlates with the intensity of multimodal limb treatment and patient-centered outcomes in patients with threatened limbs managed in a limb preservation center.

PubMed

Robinson, William P; Loretz, Lorraine; Hanesian, Colleen; Flahive, Julie; Bostrom, John; Lunig, Nicholas; Schanzer, Andres; Messina, Louis

2017-08-01

The Society for Vascular Surgery Wound, Ischemia, foot Infection (WIfI) system aims to stratify threatened limbs according to their anticipated natural history and estimate the likelihood of benefit from revascularization, but whether it accurately stratifies outcomes in limbs undergoing aggressive treatment for limb salvage is unknown. We investigated whether the WIfI stage correlated with the intensity of limb treatment required and patient-centered outcomes. We stratified limbs from a prospectively maintained database of consecutive patients referred to a limb preservation center according to WIfI stage (October 2013-May 2015). Comorbidities, multimodal limb treatment, including foot operations and revascularization, and patient-centered outcomes (wound healing, limb salvage, amputation-free survival, maintenance of ambulatory and independent living status, and mortality) were compared among WIfI stages. Multivariate analysis was performed to identify predictors of wound healing and limb salvage. We identified 280 threatened limbs encompassing all WIfI stages in 257 consecutive patients: stage 1, 48 (17%); stage 2, 67 (24%); stage 3, 64 (23%); stage 4, 83 (30%); and stage 5 (unsalvageable), 18 (6%). Operative foot débridement, minor amputation, and use of revascularization increased with increasing WIfI stage (P ≤ .04). Revascularization was performed in 106 limbs (39%), with equal use of open and endovascular procedures. Over a median follow-up of 209 days (interquartile range, 95, 340) days, 1-year Kaplan-Meier wound healing cumulative incidence was 71%, and the proportion with complete wound healing decreased with increasing WIfI stage. Major amputation was required in 26 stage 1 to 4 limbs (10%). Increasing WIfI stage was associated with decreased 1-year Kaplan-Meier limb salvage (stage 1: 96%, stage 2: 84%, stage 3: 90%, and stage 4: 78%; P = .003) and amputation-free survival (P = .006). Stage 4 WIfI independently predicted amputation (hazard ratio, 12; 95% confidence interval, 1.6-94). Amputation rates in patients with severe Ischemia grade 3 were lower in those who underwent revascularization than in those who did not (14% vs 41%; P = .01) Ambulatory and independent living status at follow-up deteriorated significantly from baseline in stage 4 but not stage 1 to 3 patients. Mortality was not different between WIfI stages. In patients treated aggressively for limb salvage, WIfI stage correlated with intensity of multimodal limb treatment and with limb salvage and patient-centered outcomes at 1 year. Revascularization improved limb salvage in severe ischemia. These data support the Society for Vascular Surgery WIfI system as a powerful tool to risk-stratify patients with threatened limbs and guide treatment. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Spatial Coupling Affects Both Homologous and Non-Homologous Limbs

ERIC Educational Resources Information Center

Huh, Carey Y.

2004-01-01

The present study examined the interaction between limb movements in space. The amount of interaction was measured by how much moving one limb affected the movement of another limb. Participants were 24 right-handed university students (19 female, mean AGE=19 years). The task was to draw lines with the right hand while moving another limb in lines…

Isolated primary lymphedema tarda of the upper limb.

PubMed

Shariati, Farzaneh; Ravari, Hasan; Kazemzadeh, Gholamhossein; Sadeghi, Ramin

2013-03-01

Primary lymphedema tarda is considered as a congenital disease with late presentation. Primary lymphedema tarda usually affects lower limbs, and primary lymphedema tarda of the upper limbs usually accompanies lower limb lymphedema. In the current case report, we present an 80-year-old male patient with isolated left upper limb swelling that lymphoscintigraphy imaging proved to be lymphedema.

Evaluation of Limb-Girdle Muscular Dystrophy

ClinicalTrials.gov

2014-03-06

Becker Muscular Dystrophy; Limb-Girdle Muscular Dystrophy, Type 2A (Calpain-3 Deficiency); Limb-Girdle Muscular Dystrophy, Type 2B (Miyoshi Myopathy, Dysferlin Deficiency); Limb-Girdle Muscular Dystrophy, Type 2I (FKRP-deficiency)

Probability of Regenerating a Normal Limb After Bite Injury in the Mexican Axolotl (Ambystoma mexicanum).

PubMed

Thompson, Sierra; Muzinic, Laura; Muzinic, Christopher; Niemiller, Matthew L; Voss, S Randal

2014-06-01

Multiple factors are thought to cause limb abnormalities in amphibian populations by altering processes of limb development and regeneration. We examined adult and juvenile axolotls ( Ambystoma mexicanum ) in the Ambystoma Genetic Stock Center (AGSC) for limb and digit abnormalities to investigate the probability of normal regeneration after bite injury. We observed that 80% of larval salamanders show evidence of bite injury at the time of transition from group housing to solitary housing. Among 717 adult axolotls that were surveyed, which included solitary-housed males and group-housed females, approximately half presented abnormalities, including examples of extra or missing digits and limbs, fused digits, and digits growing from atypical anatomical positions. Bite injury likely explains these limb defects, and not abnormal development, because limbs with normal anatomy regenerated after performing rostral amputations. We infer that only 43% of AGSC larvae will present four anatomically normal looking adult limbs after incurring a bite injury. Our results show regeneration of normal limb anatomy to be less than perfect after bite injury.

Limb Dominance and Its Effects on the Benefits of Intralimb Transfer of Learning: A Visuomotor Aiming Task.

PubMed

Aiken, Christopher A; Pan, Zhujun; Van Gemmert, Arend W A

2015-01-01

Research has attempted to address what characteristics benefit from transfer of learning; however, it is still unclear which characteristics are effector dependent or independent. Furthermore, it is not clear if intralimb transfer shows, similarly to interlimb transfer, an asymmetry of benefits between the upper limbs. The purpose of the current study is to examine if effector independence effects emerge, as observed in interlimb transfer studies, when transfer to new effector group within the same limb occurs, and whether the pattern of intralimb transfer benefits differ between the limbs. Our results suggest that a visuomotor task transfers within both limbs, even though the transfer benefits within the limbs seem to differ. This was supported by more transfer occurring in the dominant limb than the nondominant limb. Potential control mechanisms used for intralimb transfer are discussed.

Movement patterns of limb coordination in infant rolling.

PubMed

Kobayashi, Yoshio; Watanabe, Hama; Taga, Gentaro

2016-12-01

Infants must perform dynamic whole-body movements to initiate rolling, a key motor skill. However, little is known regarding limb coordination and postural control in infant rolling. To address this lack of knowledge, we examined movement patterns and limb coordination during rolling in younger infants (aged 5-7 months) that had just begun to roll and in older infants (aged 8-10 months) with greater rolling experience. Due to anticipated difficulty in obtaining measurements over the second half of the rolling sequence, we limited our analysis to the first half. Ipsilateral and contralateral limbs were identified on the basis of rolling direction and were classified as either a stationary limb used for postural stability or a moving limb used for controlled movement. We classified the observed movement patterns by identifying the number of stationary limbs and the serial order of combinational limb movement patterns. Notably, older infants performed more movement patterns that involved a lower number of stationary limbs than younger infants. Despite the wide range of possible movement patterns, a small group of basic patterns dominated in both age groups. Our results suggest that the fundamental structure of limb coordination during rolling in the early acquisition stages remains unchanged until at least 8-10 months of age. However, compared to younger infants, older infants exhibited a greater ability to select an effective rotational movement by positioning themselves with fewer stationary limbs and performing faster limb movements.

Limb deficiency and prosthetic management. 2. Aging with limb loss.

PubMed

Flood, Katherine M; Huang, Mark E; Roberts, Toni L; Pasquina, Paul F; Nelson, Virginia S; Bryant, Phillip R

2006-03-01

This self-directed learning module highlights the issues faced by people aging with limb loss. It is part of the study guide on limb deficiency and vascular rehabilitation in the Self-Directed Physiatric Education Program for practitioners and trainees in physical medicine and rehabilitation. This article specifically focuses on the impact that limb loss has on health and physical function throughout the life span. Case examples are used to illustrate what effect limb loss in childhood or young adulthood has on the incidence and management of new impairments or disease processes commonly associated with aging. To discuss the impact of early-life limb loss on the incidence and management of physiologic and functional changes associated with aging.

Upper Limb Posture Estimation in Robotic and Virtual Reality-Based Rehabilitation

PubMed Central

Cortés, Camilo; Ardanza, Aitor; Molina-Rueda, F.; Cuesta-Gómez, A.; Ruiz, Oscar E.

2014-01-01

New motor rehabilitation therapies include virtual reality (VR) and robotic technologies. In limb rehabilitation, limb posture is required to (1) provide a limb realistic representation in VR games and (2) assess the patient improvement. When exoskeleton devices are used in the therapy, the measurements of their joint angles cannot be directly used to represent the posture of the patient limb, since the human and exoskeleton kinematic models differ. In response to this shortcoming, we propose a method to estimate the posture of the human limb attached to the exoskeleton. We use the exoskeleton joint angles measurements and the constraints of the exoskeleton on the limb to estimate the human limb joints angles. This paper presents (a) the mathematical formulation and solution to the problem, (b) the implementation of the proposed solution on a commercial exoskeleton system for the upper limb rehabilitation, (c) its integration into a rehabilitation VR game platform, and (d) the quantitative assessment of the method during elbow and wrist analytic training. Results show that this method properly estimates the limb posture to (i) animate avatars that represent the patient in VR games and (ii) obtain kinematic data for the patient assessment during elbow and wrist analytic rehabilitation. PMID:25110698

Effects of varying inter-limb spacing to limb length ratio in metachronal swimming

NASA Astrophysics Data System (ADS)

Lai, Hong Kuan; Merkel, Rachael; Santhanakrishnan, Arvind

2016-11-01

Crustaceans such as shrimp, krill and crayfish swim by rhythmic paddling of four to five pairs of closely spaced limbs. Each pair is phase-shifted in time relative to the neighboring pair, resulting in a metachronal wave that travels in the direction of animal motion. The broad goal of this study is to investigate how the mechanical design of the swimming limbs affect scalability of metachronal swimming in terms of limb-based Reynolds number (Re). A scaled robotic model of metachronal paddling was developed, consisting of four pairs of hinged acrylic plates actuated using stepper motors that were immersed in a rectangular tank containing water-glycerin fluid medium. 2D PIV measurements show that the propulsive jets transition from being primarily horizontal (thrust-producing direction) at Re of order 10 to angled vertically at Re of order 100. The ratio of inter-limb spacing to limb length among metachronal swimming organisms ranges between 0.2 to 0.65. 2D PIV will be used to examine the jets generated between adjacent limbs for varying inter-limb spacing to limb length ratios. The effect of increasing this ratio to beyond the biologically observed range will be discussed.

Ectodermal Wnt6 is an early negative regulator of limb chondrogenesis in the chicken embryo

PubMed Central

2010-01-01

Background Pattern formation of the limb skeleton is regulated by a complex interplay of signaling centers located in the ectodermal sheath and mesenchymal core of the limb anlagen, which results, in the forelimb, in the coordinate array of humerus, radius, ulna, carpals, metacarpals and digits. Much less understood is why skeletal elements form only in the central mesenchyme of the limb, whereas muscle anlagen develop in the peripheral mesenchyme ensheathing the chondrogenic center. Classical studies have suggested a role of the limb ectoderm as a negative regulator of limb chondrogenesis. Results In this paper, we investigated the molecular nature of the inhibitory influence of the ectoderm on limb chondrogenesis in the avian embryo in vivo. We show that ectoderm ablation in the early limb bud leads to increased and ectopic expression of early chondrogenic marker genes like Sox9 and Collagen II, indicating that the limb ectoderm inhibits limb chondrogenesis at an early stage of the chondrogenic cascade. To investigate the molecular nature of the inhibitory influence of the ectoderm, we ectopically expressed Wnt6, which is presently the only known Wnt expressed throughout the avian limb ectoderm, and found that Wnt6 overexpression leads to reduced expression of the early chondrogenic marker genes Sox9 and Collagen II. Conclusion Our results suggest that the inhibitory influence of the ectoderm on limb chondrogenesis acts on an early stage of chondrogenesis upsteam of Sox9 and Collagen II. We identify Wnt6 as a candidate mediator of ectodermal chondrogenic inhibition in vivo. We propose a model of Wnt-mediated centripetal patterning of the limb by the surface ectoderm. PMID:20334703

Neural Adaptations Associated with Interlimb Transfer in a Ballistic Wrist Flexion Task

PubMed Central

Ruddy, Kathy L.; Rudolf, Anne K.; Kalkman, Barbara; King, Maedbh; Daffertshofer, Andreas; Carroll, Timothy J.; Carson, Richard G.

2016-01-01

Cross education is the process whereby training of one limb gives rise to increases in the subsequent performance of its opposite counterpart. The execution of many unilateral tasks is associated with increased excitability of corticospinal projections from primary motor cortex (M1) to the opposite limb. It has been proposed that these effects are causally related. Our aim was to establish whether changes in corticospinal excitability (CSE) arising from prior training of the opposite limb determine levels of interlimb transfer. We used three vision conditions shown previously to modulate the excitability of corticospinal projections to the inactive (right) limb during wrist flexion movements performed by the training (left) limb. These were: (1) mirrored visual feedback of the training limb; (2) no visual feedback of either limb; and (3) visual feedback of the inactive limb. Training comprised 300 discrete, ballistic wrist flexion movements executed as rapidly as possible. Performance of the right limb on the same task was assessed prior to, at the mid point of, and following left limb training. There was no evidence that variations in the excitability of corticospinal projections (assessed by transcranial magnetic stimulation (TMS)) to the inactive limb were associated with, or predictive of, the extent of interlimb transfer that was expressed. There were however associations between alterations in muscle activation dynamics observed for the untrained limb, and the degree of positive transfer that arose from training of the opposite limb. The results suggest that the acute adaptations that mediate the bilateral performance gains realized through unilateral practice of this ballistic wrist flexion task are mediated by neural elements other than those within M1 that are recruited at rest by single-pulse TMS. PMID:27199722

Minor Morbidity with Emergency Tourniquet Use to Stop Bleeding in Severe Limb Trauma: Research, History, and Reconciling Advocates and Abolitionists

DTIC Science & Technology

2011-07-01

unknown. If we say these 13 limbs had only one tourniquet per limb, then the total number of tourniquets was 875. The body regions ( forearm , arm ...leg, thigh) where the tourniquets were applied to the 651 limbs included 436 thighs, 162 arms , 46 legs, 13 forearms , 8 limbs where the tourniquets...I body region ( forearm 0113, thigh 2/436, leg, 1146, and arm : 6/162). The overall rate of side-by-side use was 20% (93 • of 461 limbs). There

Managing residual limb hyperhidrosis in wounded warriors.

PubMed

Pace, Sarah; Kentosh, Joshua

2016-06-01

Residual limb dermatologic problems are a common concern among young active traumatic amputee patients who strive to maintain an active lifestyle. Hyperhidrosis of residual limbs is a recognized inciting factor that often contributes to residual limb dermatoses and is driven by the design of the prosthetic liner covering the residual limb. Treatment of hyperhidrosis in this population presents a unique challenge. Several accepted treatments of hyperhidrosis can offer some relief but have been limited by lack of results or side-effect profiles. Microwave thermal ablation has presented an enticing potential for residual limb hyperhidrosis.

In vivo locomotor strain in the hindlimb bones of alligator mississippiensis and iguana iguana: implications for the evolution of limb bone safety factor and non-sprawling limb posture

PubMed

Blob; Biewener

1999-05-01

Limb postures of terrestrial tetrapods span a continuum from sprawling to fully upright; however, most experimental investigations of locomotor mechanics have focused on mammals and ground-dwelling birds that employ parasagittal limb kinematics, leaving much of the diversity of tetrapod locomotor mechanics unexplored. This study reports measurements of in vivo locomotor strain from the limb bones of lizard (Iguana iguana) and crocodilian (Alligator mississippiensis) species, animals from previously unsampled phylogenetic lineages with non-parasagittal limb posture and kinematics. Principal strain orientations and shear strain magnitudes indicate that the limb bones of these species experience considerable torsion during locomotion. This contrasts with patterns commonly observed in mammals, but matches predictions from kinematic observations of axial rotation in lizard and crocodilian limbs. Comparisons of locomotor load magnitudes with the mechanical properties of limb bones in Alligator and Iguana indicate that limb bone safety factors in bending for these species range from 5.5 to 10.8, as much as twice as high as safety factors previously calculated for mammals and birds. Limb bone safety factors in shear (3.9-5.4) for Alligator and Iguana are also moderately higher than safety factors to yield in bending for birds and mammals. Finally, correlations between limb posture and strain magnitudes in Alligator show that at some recording locations limb bone strains can increase during upright locomotion, in contrast to expectations based on size-correlated changes in posture among mammals that limb bone strains should decrease with the use of an upright posture. These data suggest that, in some lineages, strain magnitudes may not have been maintained at constant levels through the evolution of a non-sprawling posture unless the postural change was accompanied by a shift to parasagittal kinematics or by an evolutionary decrease in body size.

Interlimb coordination during the stance phase of gait in subjects with stroke.

PubMed

Sousa, Andreia S P; Silva, Augusta; Santos, Rubim; Sousa, Filipa; Tavares, João Manuel R S

2013-12-01

To analyze the relation between contralesional and ipsilesional limbs in subjects with stroke during step-to-step transition of walking. Observational, transversal, analytical study with a convenience sample. Physical medicine and rehabilitation clinic. Subjects (n=16) with poststroke hemiparesis with the ability to walk independently and healthy controls (n=22). Not applicable. Bilateral lower limbs electromyographic activity of the soleus (SOL), gastrocnemius medialis, tibialis anterior, biceps femoris, rectus femoris, and vastus medialis (VM) muscles and the ground reaction force were analyzed during double-support and terminal stance phases of gait. The propulsive impulse of the contralesional trailing limb was negatively correlated with the braking impulse of the leading limb during double support (r=-.639, P=.01). A moderate functional relation was observed between thigh muscles (r=-.529, P=.035), and a strong and moderate dysfunctional relation was found between the plantar flexors of the ipsilesional limb and the vastus medialis of the contralesional limb, respectively (SOL-VM, r=-.80, P<.001; gastrocnemius medialis-VM, r=-.655, P=.002). Also, a functional moderate negative correlation was found between the SOL and rectus femoris muscles of the ipsilesional limb during terminal stance and between the SOL (r=-.506, P=.046) and VM (r=-.518, P=.04) muscles of the contralesional limb during loading response, respectively. The trailing limb relative impulse contribution of the contralesional limb was lower than the ipsilesional limb of subjects with stroke (P=.02) and lower than the relative impulse contribution of the healthy limb (P=.008) during double support. The findings obtained suggest that the lower performance of the contralesional limb in forward propulsion during gait is related not only to contralateral supraspinal damage but also to a dysfunctional influence of the ipsilesional limb. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Cryopreservation and replantation of amputated rat hind limbs

PubMed Central

2014-01-01

Background In spite of the relatively high success rate of limb replantation, many patients cannot undergo replantation surgery because the preservation time of an amputated limb is only about six hours. In addition, although allotransplantation of composite tissues is being performed more commonly with increasingly greater success rates, the shortage of donors limits the number of patients that can be treated. So the purpose of this study is to examine the feasibility of cryopreservation and replantation of limbs in a rat model. Methods Twelve five-month-old Sprague-Dawley rats were divided evenly into group A (above-knee amputation) and group B (Syme’s amputation). One hind limb was amputated from each rat. The limbs were irrigated with cryoprotectant, cooled in a controlled manner to -140°C, and placed in liquid nitrogen. Thawing and replantation were performed 14 days later. Results In group A, the limbs became swollen after restoration of blood flow resulting in blood vessel compression and all replantations failed. In group B, restoration of blood flow was noted in all limbs after replantation. In one case, the rat chewed the replanted limb and replantation failed. The other five rats were followed for three months with no abnormalities noted in the replanted limbs. Conclusions Limbs with a minimal amount of muscle tissue can be successfully cryopreserved and replanted. PMID:24886622

Suppression of morphogenesis in embryonic mouse limbs exposed in vitro to excess gravity.

PubMed

Duke, J C

1983-06-01

This paper is a report of the first investigation of the effect of excess gravity on in vitro mammalian limb chondrogenesis. Limb buds from mice of various gestational stages were exposed to excess gravity (2.6G) using a culture centrifuge. Both forelimbs and hind limbs were cultured and the development of various limb elements was scored after four to six days. The 2.6G force significantly depressed the development of limb elements when applied during the teratogen-sensitive period of chondrogenesis. There was a proximodistal gradient of sensitivity to excess gravity in the limb with proximal structures being less susceptible than distal ones. In some cases, proximal limb elements present prior to explantation disappeared upon exposure to excess gravity. Hypergravity's teratogenic effect is assumed to operate via changes in tension and/or pressure on the cells, accompanied by alterations in cell morphometry and membrane properties.

Automatic limb identification and sleeping parameters assessment for pressure ulcer prevention.

PubMed

Baran Pouyan, Maziyar; Birjandtalab, Javad; Nourani, Mehrdad; Matthew Pompeo, M D

2016-08-01

Pressure ulcers (PUs) are common among vulnerable patients such as elderly, bedridden and diabetic. PUs are very painful for patients and costly for hospitals and nursing homes. Assessment of sleeping parameters on at-risk limbs is critical for ulcer prevention. An effective assessment depends on automatic identification and tracking of at-risk limbs. An accurate limb identification can be used to analyze the pressure distribution and assess risk for each limb. In this paper, we propose a graph-based clustering approach to extract the body limbs from the pressure data collected by a commercial pressure map system. A robust signature-based technique is employed to automatically label each limb. Finally, an assessment technique is applied to evaluate the experienced stress by each limb over time. The experimental results indicate high performance and more than 94% average accuracy of the proposed approach. Copyright © 2016 Elsevier Ltd. All rights reserved.

Successful limb salvage through staged bypass combined with free gracilis muscle transfer for critical limb ischemia with osteomyelitis after failed endovascular therapy.

PubMed

Miyake, Keisuke; Kikuchi, Shinsuke; Okuda, Hiroko; Koya, Atsuhiro; Abe, Satomi; Sawa, Yoshiki; Ota, Tetsuo; Azuma, Nobuyoshi

2018-05-02

Critical limb ischemia with osteomyelitis is so difficult to treat that even appropriate revascularization and wound therapy cannot achieve limb salvage because of uncontrollable infection. It is still difficult to judge the possibility of limb salvage before revascularization. A 73-year-old male complained of a small ulcer on his left toe, which was treated with multiple endovascular therapy. After failed endovascular therapy, he suffered extensive tissue loss with tibial osteomyelitis. We carried out staged surgery that was composed of dual bypass to the sural artery and posterior tibial artery. After intensive debridement and wound care, insertion of a subsequent free gracilis muscle flap to cover the exposed tibial bone was performed, achieving functional limb salvage. Even in the threatened limb with extensive tissue loss and osteomyelitis, intensive and multidisciplinary treatment with staged revascularization, muscle transfer, and appropriate wound care achieved functional limb salvage.

Effect of Upper Limb Deformities on Gross Motor and Upper Limb Functions in Children with Spastic Cerebral Palsy

ERIC Educational Resources Information Center

Park, Eun Sook; Sim, Eun Geol; Rha, Dong-wook

2011-01-01

The aims of this study were to investigate the nature and extent of upper limb deformities via the use of various classifications, and to analyze the relationship between upper limb deformities and gross motor or upper limb functionality levels. Upper extremity data were collected from 234 children with spastic cerebral palsy (CP) who were…

Epidemiology of race-day distal limb fracture in flat racing Thoroughbreds in Great Britain (2000 to 2013).

PubMed

Rosanowski, S M; Chang, Y M; Stirk, A J; Verheyen, K L P

2018-05-28

A key focus of the racing industry is to minimise the number of race-day distal limb fractures, although no studies have identified risk factors for both fatal and non-fatal distal limb fractures. To determine risk factors for race-day distal limb fractures experienced by Thoroughbred racehorses participating in flat racing in Great Britain (GB). Retrospective cohort. Information was collected from all flat racing starts occurring on GB racecourses between 2000 and 2013, including horse, race, course, trainer and jockey data for each horse start and race-day injury data as reported by on-course veterinarians. Associations between exposure variables and cases of distal limb fracture were assessed using mixed effects logistic regression analyses using data from all starts, and turf starts only. A total of 806,764 starts and 624 cases of distal limb fracture were included, of which 548,571 starts and 379 cases of distal limb fracture occurred on turf surfaces. In both models, increasing firmness of the going, increasing racing distance and horses in their first year of racing were at a higher risk of distal limb fracture, while increasing number of previous race starts were protective. Trainer performance was associated with distal limb fracture. Generally, the risk of distal limb fracture increased with increasing horse age. Starts in selling or claiming races or Group 1, Group 3 or claiming races were at higher odds of distal limb fracture in the all starts and turf models, respectively. Clinical diagnosis of distal limb fracture and all types of distal limb fracture considered as one outcome. This study confirmed previously identified risk factors for distal limb fracture including going, race distance and number of horse starts. Novel risk factors were related to trainer and horse performance, and race type. Identification of at risk groups will help inform interventions to reduce distal limb fracture occurrence in flat racing horses. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Scale effects between body size and limb design in quadrupedal mammals.

PubMed

Kilbourne, Brandon M; Hoffman, Louwrens C

2013-01-01

Recently the metabolic cost of swinging the limbs has been found to be much greater than previously thought, raising the possibility that limb rotational inertia influences the energetics of locomotion. Larger mammals have a lower mass-specific cost of transport than smaller mammals. The scaling of the mass-specific cost of transport is partly explained by decreasing stride frequency with increasing body size; however, it is unknown if limb rotational inertia also influences the mass-specific cost of transport. Limb length and inertial properties--limb mass, center of mass (COM) position, moment of inertia, radius of gyration, and natural frequency--were measured in 44 species of terrestrial mammals, spanning eight taxonomic orders. Limb length increases disproportionately with body mass via positive allometry (length ∝ body mass(0.40)); the positive allometry of limb length may help explain the scaling of the metabolic cost of transport. When scaled against body mass, forelimb inertial properties, apart from mass, scale with positive allometry. Fore- and hindlimb mass scale according to geometric similarity (limb mass ∝ body mass(1.0)), as do the remaining hindlimb inertial properties. The positive allometry of limb length is largely the result of absolute differences in limb inertial properties between mammalian subgroups. Though likely detrimental to locomotor costs in large mammals, scale effects in limb inertial properties appear to be concomitant with scale effects in sensorimotor control and locomotor ability in terrestrial mammals. Across mammals, the forelimb's potential for angular acceleration scales according to geometric similarity, whereas the hindlimb's potential for angular acceleration scales with positive allometry.

Transcriptomic insights into the genetic basis of mammalian limb diversity.

PubMed

Maier, Jennifer A; Rivas-Astroza, Marcelo; Deng, Jenny; Dowling, Anna; Oboikovitz, Paige; Cao, Xiaoyi; Behringer, Richard R; Cretekos, Chris J; Rasweiler, John J; Zhong, Sheng; Sears, Karen E

2017-03-23

From bat wings to whale flippers, limb diversification has been crucial to the evolutionary success of mammals. We performed the first transcriptome-wide study of limb development in multiple species to explore the hypothesis that mammalian limb diversification has proceeded through the differential expression of conserved shared genes, rather than by major changes to limb patterning. Specifically, we investigated the manner in which the expression of shared genes has evolved within and among mammalian species. We assembled and compared transcriptomes of bat, mouse, opossum, and pig fore- and hind limbs at the ridge, bud, and paddle stages of development. Results suggest that gene expression patterns exhibit larger variation among species during later than earlier stages of limb development, while within species results are more mixed. Consistent with the former, results also suggest that genes expressed at later developmental stages tend to have a younger evolutionary age than genes expressed at earlier stages. A suite of key limb-patterning genes was identified as being differentially expressed among the homologous limbs of all species. However, only a small subset of shared genes is differentially expressed in the fore- and hind limbs of all examined species. Similarly, a small subset of shared genes is differentially expressed within the fore- and hind limb of a single species and among the forelimbs of different species. Taken together, results of this study do not support the existence of a phylotypic period of limb development ending at chondrogenesis, but do support the hypothesis that the hierarchical nature of development translates into increasing variation among species as development progresses.

Deep-time evolution of regeneration and preaxial polarity in tetrapod limb development.

PubMed

Fröbisch, Nadia B; Bickelmann, Constanze; Olori, Jennifer C; Witzmann, Florian

2015-11-12

Among extant tetrapods, salamanders are unique in showing a reversed preaxial polarity in patterning of the skeletal elements of the limbs, and in displaying the highest capacity for regeneration, including full limb and tail regeneration. These features are particularly striking as tetrapod limb development has otherwise been shown to be a highly conserved process. It remains elusive whether the capacity to regenerate limbs in salamanders is mechanistically and evolutionarily linked to the aberrant pattern of limb development; both are features classically regarded as unique to urodeles. New molecular data suggest that salamander-specific orphan genes play a central role in limb regeneration and may also be involved in the preaxial patterning during limb development. Here we show that preaxial polarity in limb development was present in various groups of temnospondyl amphibians of the Carboniferous and Permian periods, including the dissorophoids Apateon and Micromelerpeton, as well as the stereospondylomorph Sclerocephalus. Limb regeneration has also been reported in Micromelerpeton, demonstrating that both features were already present together in antecedents of modern salamanders 290 million years ago. Furthermore, data from lepospondyl 'microsaurs' on the amniote stem indicate that these taxa may have shown some capacity for limb regeneration and were capable of tail regeneration, including re-patterning of the caudal vertebral column that is otherwise only seen in salamander tail regeneration. The data from fossils suggest that salamander-like regeneration is an ancient feature of tetrapods that was subsequently lost at least once in the lineage leading to amniotes. Salamanders are the only modern tetrapods that retained regenerative capacities as well as preaxial polarity in limb development.

Scale Effects between Body Size and Limb Design in Quadrupedal Mammals

PubMed Central

Kilbourne, Brandon M.; Hoffman, Louwrens C.

2013-01-01

Recently the metabolic cost of swinging the limbs has been found to be much greater than previously thought, raising the possibility that limb rotational inertia influences the energetics of locomotion. Larger mammals have a lower mass-specific cost of transport than smaller mammals. The scaling of the mass-specific cost of transport is partly explained by decreasing stride frequency with increasing body size; however, it is unknown if limb rotational inertia also influences the mass-specific cost of transport. Limb length and inertial properties – limb mass, center of mass (COM) position, moment of inertia, radius of gyration, and natural frequency – were measured in 44 species of terrestrial mammals, spanning eight taxonomic orders. Limb length increases disproportionately with body mass via positive allometry (length ∝ body mass0.40); the positive allometry of limb length may help explain the scaling of the metabolic cost of transport. When scaled against body mass, forelimb inertial properties, apart from mass, scale with positive allometry. Fore- and hindlimb mass scale according to geometric similarity (limb mass ∝ body mass1.0), as do the remaining hindlimb inertial properties. The positive allometry of limb length is largely the result of absolute differences in limb inertial properties between mammalian subgroups. Though likely detrimental to locomotor costs in large mammals, scale effects in limb inertial properties appear to be concomitant with scale effects in sensorimotor control and locomotor ability in terrestrial mammals. Across mammals, the forelimb's potential for angular acceleration scales according to geometric similarity, whereas the hindlimb's potential for angular acceleration scales with positive allometry. PMID:24260117

The effects of laterality on obstacle crossing performance in unilateral trans-tibial amputees.

PubMed

De Asha, Alan R; Buckley, John G

2015-05-01

Unilateral trans-tibial amputees have bilaterally reduced toe clearance, and an increased risk of foot contact, while crossing obstacles compared to the able-bodied. While the able-bodied tend to lead with a 'preferred' limb it is equivocal whether amputees prefer to lead with the intact or prosthetic limb. This study determined the effects of laterality, compared to side of amputation, on amputees' obstacle crossing performance. To help understand why laterality could affect performance we also assessed knee proprioception for both limbs. Foot placement and toe clearance parameters were recorded while nine amputees crossed obstacles of varying heights leading with both their intact and prosthetic limbs. Joint-position sense was also assessed. Participants self-reported which limb was their preferred (dominant) limb. There were no significant differences in foot placements or toe clearance variability across lead-limb conditions. There were no significant differences in toe clearance between intact and prosthetic lead-limbs (p=0.28) but toe clearance was significantly higher when amputees led with their preferred compared to non-preferred limb (p=0.025). There was no difference in joint-position sense between the intact and residual knees (p=0.34) but joint-position sense tended to be more accurate for the preferred, compared to non-preferred limb (p=0.08). Findings suggest that, despite the mechanical constraints imposed by use of a prosthesis, laterality may be as important in lower-limb amputees as it is in the able bodied. This suggests that amputees should be encouraged to cross obstacles leading with their preferred limb. Copyright © 2015. Published by Elsevier Ltd.

Hind limb malformations in free-living northern leopard frogs (Rana pipiens) from Maine, Minnesota, and Vermont suggest multiple etiologies

USGS Publications Warehouse

Meteyer, C.U.; Loeffler, I.K.; Fallon, J.F.; Converse, K.A.; Green, E.; Helgen, J.C.; Kersten, S.; Levey, R.; Eaton-Poole, L.; Burkhart, J.G.

2000-01-01

Background Reports of malformed frogs have increased throughout the North American continent in recent years. Most of the observed malformations have involved the hind limbs. The goal of this study was to accurately characterize the hind limb malformations in wild frogs as an important step toward understanding the possible etiologies. Methods During 1997 and 1998, 182 recently metamorphosed northern leopard frogs (Rana pipiens) were collected from Minnesota, Vermont, and Maine. Malformed hind limbs were present in 157 (86%) of these frogs, which underwent necropsy and radiographic evaluation at the National Wildlife Health Center. These malformations are described in detail and classified into four major categories: (1) no limb (amelia); (2) multiple limbs or limb elements (polymelia, polydactyly, polyphalangy); (3) reduced limb segments or elements (phocomelia, ectromelia, ectrodactyly, and brachydactyly; and (4) distally complete but malformed limb (bone rotations, bridging, skin webbing, and micromelia). Results Amelia and reduced segments and/or elements were the most common finding. Frogs with bilateral hind limb malformations were not common, and in only eight of these 22 frogs were the malformations symmetrical. Malformations of a given type tended to occur in frogs collected from the same site, but the types of malformations varied widely among all three states, and between study sites within Minnesota. Conclusions Clustering of malformation type suggests that developmental events may produce a variety of phenotypes depending on the timing, sequence, and severity of the environmental insult. Hind limb malformations in free-living frogs transcend current mechanistic explanations of tetrapod limb development.

Genetics Home Reference: limb-girdle muscular dystrophy

MedlinePlus

... age of onset, and features of limb-girdle muscle dystrophy vary among the many subtypes of this condition ... occurs in some people with limb-girdle muscular dystrophy . Weakening of the heart muscle (cardiomyopathy) occurs in some forms of limb-girdle ...

Postoperative limb alignment and its determinants after minimally invasive Oxford medial unicompartmental knee arthroplasty.

PubMed

Mullaji, Arun B; Shetty, Gautam M; Kanna, Raj

2011-09-01

One hundred twenty-two consecutive minimally invasive Oxford phase 3 medial unicompartmental knee arthroplasties in 109 patients were evaluated for postoperative limb alignment and the influence of factors such as preoperative limb alignment, age, body mass index, sex, insert thickness, and surgeon's experience. The mean mechanical preoperative hip-knee-ankle (HKA) angle of 172.2° ± 3.1° improved to 177.1° ± 2.9° postoperatively. In 75% of the limbs, the HKA angle was restored to within an acceptable alignment of 177° ± 3°, 14% of the limbs were in excessive varus (<174°), and 11% were in valgus (>180°). Only preoperative HKA angle was predictive of postoperative HKA angle. Although most of the limbs had acceptable limb alignment after unicompartmental knee arthroplasty, limbs with more severe preoperative varus deformity had a tendency to remain in excessive varus, and limbs with lesser preoperative varus deformity had a greater tendency to go into valgus postoperatively. Copyright © 2011 Elsevier Inc. All rights reserved.

Probability of regenerating a normal limb after bite injury in the Mexican axolotl (Ambystoma mexicanum)

PubMed Central

Thompson, Sierra; Muzinic, Laura; Muzinic, Christopher; Niemiller, Matthew L.

2014-01-01

Abstract Multiple factors are thought to cause limb abnormalities in amphibian populations by altering processes of limb development and regeneration. We examined adult and juvenile axolotls (Ambystoma mexicanum) in the Ambystoma Genetic Stock Center (AGSC) for limb and digit abnormalities to investigate the probability of normal regeneration after bite injury. We observed that 80% of larval salamanders show evidence of bite injury at the time of transition from group housing to solitary housing. Among 717 adult axolotls that were surveyed, which included solitary‐housed males and group‐housed females, approximately half presented abnormalities, including examples of extra or missing digits and limbs, fused digits, and digits growing from atypical anatomical positions. Bite injury probably explains these limb defects, and not abnormal development, because limbs with normal anatomy regenerated after performing rostral amputations. We infer that only 43% of AGSC larvae will present four anatomically normal looking adult limbs after incurring a bite injury. Our results show regeneration of normal limb anatomy to be less than perfect after bite injury. PMID:25745564

Comparison of 2-limb versus 3-limb electrodiagnostic studies in the evaluation of chronic inflammatory demyelinating polyneuropathy.

PubMed

Vo, Mary L; Hanineva, Aneliya; Chin, Russell L; Carey, Bridget T; Latov, Norman; Langsdorf, Jennifer A

2015-04-01

European Federation of Neurological Societies/Peripheral Nerve Society electrodiagnostic (EDx) criteria for the definite diagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP) require the presence of demyelinating findings (DF) in at least 2 nerves. Data are lacking, however, regarding the optimal number of nerves to test. We retrospectively reviewed EDx data from 53 patients with CIDP and compared the number of DF found on 2- and 3-limb testing. A median of 3 (range 2-5) DF were found on 2-limb testing compared with 5 (range 4-7) DF when 3 limbs were evaluated. Two-limb EDx studies were sufficient to diagnose definite CIDP in 92.3% of typical, 84.2% of asymmetric, and 66.7% of distal phenotypes. Testing a third limb increased diagnostic certainty in 11 patients (20.8%) to definite CIDP. Three-limb testing may increase diagnostic sensitivity of definite CIDP, especially in patients with atypical phenotypes. Larger prospective studies are needed to better assess the benefit of performing 3-limb EDx studies. © 2014 Wiley Periodicals, Inc.

Regeneration and repair of human digits and limbs: fact and fiction

PubMed Central

Cheng, Tsun‐Chih

2015-01-01

Abstract A variety of digit and limb repair and reconstruction methods have been used in different clinical settings, but regeneration remains an item on every plastic surgeon's “wish list.” Although surgical salvage techniques are continually being improved, unreplantable digits and limbs are still abundant. We comprehensively review the structural and functional salvage methods in clinical practice, from the peeling injuries of small distal fingertips to multisegmented amputated limbs, and the developmental and tissue engineering approaches for regenerating human digits and limbs in the laboratory. Although surgical techniques have forged ahead, there are still situations in which digits and limbs are unreplantable. Advances in the field are delineated, and the regeneration processes of salamander limbs, lizard tails, and mouse digits and each component of tissue engineering approaches for digit‐ and limb‐building are discussed. Although the current technology is promising, there are many challenges in human digit and limb regeneration. We hope this review inspires research on the critical gap between clinical and basic science, and leads to more sophisticated digit and limb loss rescue and regeneration innovations. PMID:27499873

The effect of limb amputation on standing weight distribution in the remaining three limbs in dogs.

PubMed

Cole, Grayson Lee; Millis, Darryl

2017-01-16

Despite the fact that limb amputation is a commonly performed procedure in veterinary medicine, quantitative data regarding outcomes are lacking. The intention of this study was to evaluate the effect of limb amputation on weight distribution to the remaining three limbs at a stance in dogs. Ten dogs with a prior forelimb amputation and ten dogs with a prior hindlimb amputation; all of which had no history of orthopaedic or neural disease in the remaining three limbs were included in the study. Standing weight bearing was evaluated with a commercial stance analyzer in all dogs. Five valid trials were obtained and a mean percentage of weight bearing was calculated for each remaining limb. The dogs with a previous forelimb amputation, and also those with a previous hindlimb amputation, had the largest mean increase in weight bearing in the contralateral forelimb. In conclusion, proactive monitoring of orthopaedic disease in the contralateral forelimb may be advisable in dogs with a previous limb amputation. In addition, when determining candidacy for a limb amputation, disease of the contralateral forelimb should be thoroughly evaluated.

Shared Enhancer Activity in the Limbs and Phallus and Functional Divergence of a Limb-Genital cis-Regulatory Element in Snakes.

PubMed

Infante, Carlos R; Mihala, Alexandra G; Park, Sungdae; Wang, Jialiang S; Johnson, Kenji K; Lauderdale, James D; Menke, Douglas B

2015-10-12

The amniote phallus and limbs differ dramatically in their morphologies but share patterns of signaling and gene expression in early development. Thus far, the extent to which genital and limb transcriptional networks also share cis-regulatory elements has remained unexplored. We show that many limb enhancers are retained in snake genomes, suggesting that these elements may function in non-limb tissues. Consistent with this, our analysis of cis-regulatory activity in mice and Anolis lizards reveals that patterns of enhancer activity in embryonic limbs and genitalia overlap heavily. In mice, deletion of HLEB, an enhancer of Tbx4, produces defects in hindlimbs and genitalia, establishing the importance of this limb-genital enhancer for development of these different appendages. Further analyses demonstrate that the HLEB of snakes has lost hindlimb enhancer function while retaining genital activity. Our findings identify roles for Tbx4 in genital development and highlight deep similarities in cis-regulatory activity between limbs and genitalia. Copyright © 2015 Elsevier Inc. All rights reserved.

A Limb Action Detector Enabling People with Multiple Disabilities to Control Environmental Stimulation through Limb Action with a Nintendo Wii Remote Controller

ERIC Educational Resources Information Center

Shih, Ching-Hsiang; Chang, Man-Ling; Shih, Ching-Tien

2010-01-01

This study assessed whether two persons with multiple disabilities would be able to control environmental stimulation using limb action with a Nintendo Wii Remote Controller and a newly developed limb action detection program (LADP, i.e., a new software program that turns a Wii Remote Controller into a precise limb action detector). This study was…

Visual Feedback of the Non-Moving Limb Improves Active Joint-Position Sense of the Impaired Limb in Spastic Hemiparetic Cerebral Palsy

ERIC Educational Resources Information Center

Smorenburg, Ana R. P.; Ledebt, Annick; Deconinck, Frederik J. A.; Savelsbergh, Geert J. P.

2011-01-01

This study examined the active joint-position sense in children with Spastic Hemiparetic Cerebral Palsy (SHCP) and the effect of static visual feedback and static mirror visual feedback, of the non-moving limb, on the joint-position sense. Participants were asked to match the position of one upper limb with that of the contralateral limb. The task…

A New Limb Movement Detector Enabling People with Multiple Disabilities to Control Environmental Stimulation through Limb Swing with a Gyration Air Mouse

ERIC Educational Resources Information Center

Shih, Ching-Hsiang; Chang, Man-Ling; Shih, Ching-Tien

2010-01-01

This study assessed whether two persons with multiple disabilities would be able to control environmental stimulation using limb swing with a gyration air mouse and a newly developed limb movement detection program (LMDP, i.e., a new software program that turns a gyration air mouse into a precise limb movement detector). The study was performed…

Elevated vacuum suspension preserves residual-limb skin health in people with lower-limb amputation: Randomized clinical trial.

PubMed

Rink, Cameron; Wernke, Matthew M; Powell, Heather M; Gynawali, Surya; Schroeder, Ryan M; Kim, Jayne Y; Denune, Jeffrey A; Gordillo, Gayle M; Colvin, James M; Sen, Chandan K

2016-01-01

A growing number of clinical trials and case reports support qualitative claims that use of an elevated vacuum suspension (EVS) prosthesis improves residual-limb health on the basis of self-reported questionnaires, clinical outcomes scales, and wound closure studies. Here, we report first efforts to quantitatively assess residual-limb circulation in response to EVS. Residual-limb skin health and perfusion of people with lower-limb amputation (N = 10) were assessed during a randomized crossover study comparing EVS with nonelevated vacuum suspension (control) over a 32 wk period using noninvasive probes (transepidermal water loss, laser speckle imaging, transcutaneous oxygen measurement) and functional hyperspectral imaging approaches. Regardless of the suspension system, prosthesis donning decreased perfusion in the residual limb under resting conditions. After 16 wk of use, EVS improved residual-limb oxygenation during treadmill walking. Likewise, prosthesis-induced reactive hyperemia was attenuated with EVS following 16 wk of use. Skin barrier function was preserved with EVS but disrupted after control socket use. Taken together, outcomes suggest chronic EVS use improves perfusion and preserves skin barrier function in people with lower-limb amputation. ClinicalTrials.gov; "Evaluation of limb health associated with a prosthetic vacuum socket system": NCT01839123; https://clinicaltrials.gov/ct2/show/NCT01839123?term=NCT01839123&rank=1.

ATHLETE: A Limbed Vehicle for Solar System Exploration

NASA Technical Reports Server (NTRS)

Wilcox, Brian H.

2012-01-01

As part of the Human-Robot Systems project funded by NASA, the Jet Propulsion Laboratory has developed a vehicle called ATHLETE: the All-Terrain Hex-Limbed Extra-Terrestrial Explorer. Each vehicle is based on six wheels at the ends of six multi-degree-of-freedom limbs. Because each limb has enough degrees of freedom for use as a general-purpose leg, the wheels can be locked and used as feet to walk out of excessively soft or other extreme terrain. Since the vehicle has this alternative mode of traversing through or at least out of extreme terrain, the wheels and wheel actuators can be sized for nominal terrain. There are substantial mass savings in the wheel and wheel actuators associated with designing for nominal instead of extreme terrain. These mass savings are comparable-to or larger-than the extra mass associated with the articulated limbs. As a result, the entire mobility system, including wheels and limbs, can be about 25% lighter than a conventional mobility chassis. A side benefit of this approach is that each limb has sufficient degrees-of-freedom to use as a general-purpose manipulator (hence the name "limb" instead of "leg"). Our prototype ATHLETE vehicles have quick-disconnect tool adapters on the limbs that allow tools to be drawn out of a "tool belt" and maneuvered by the limb.

Leaping lopsided: a review of the current hypotheses regarding etiologies of limb malformations in frogs.

PubMed

Loeffler, I K; Stocum, D L; Fallon, J F; Meteyer, C U

2001-10-15

Recent progress in the investigation of limb malformations in free-living frogs has underlined the wide range in the types of limb malformations and the apparent spatiotemporal clustering of their occurrence. Here, we review the current understanding of normal and abnormal vertebrate limb development and regeneration and discuss some of the molecular events that may bring about limb malformation. Consideration of the differences between limb development and regeneration in amphibians has led us to the hypothesis that some of the observed limb malformations come about through misdirected regeneration. We report the results of a pilot study that supports this hypothesis. In this study, the distal aspect of the right hindlimb buds of X. laevis tadpoles was amputated at the pre-foot paddle stage. The tadpoles were raised in water from a pond in Minnesota at which 7% of surveyed newly metamorphosed feral frogs had malformations. Six percent (6 of 100) of the right limbs of the tadpoles raised in pond water developed abnormally. One truncated right limb was the only malformation in the control group, which was raised in dechlorinated municipal water. All unamputated limbs developed normally in both groups. Three major factors under consideration for effecting the limb malformations are discussed. These factors include environmental chemicals (primarily agrichemicals), encysted larvae (metacercariae) of trematode parasites, and increased levels of ultraviolet light. Emphasis is placed on the necessary intersection of environmental stressors and developmental events to bring about the specific malformations that are observed in free-living frog populations.

Kinematic adaptations to tripedal locomotion in dogs.

PubMed

Goldner, B; Fuchs, A; Nolte, I; Schilling, N

2015-05-01

Limb amputation often represents the only treatment option for canine patients with certain diseases or injuries of the appendicular system. Previous studies have investigated adaptations to tripedal locomotion in dogs but there is a lack of understanding of biomechanical compensatory mechanisms. This study evaluated the kinematic differences between quadrupedal and tripedal locomotion in nine healthy dogs running on a treadmill. The loss of the right pelvic limb was simulated using an Ehmer sling. Kinematic gait analysis included spatio-temporal comparisons of limb, joint and segment angles of the remaining pelvic and both thoracic limbs. The following key parameters were compared between quadrupedal and tripedal conditions: angles at touch-down and lift-off, minimum and maximum joint angles, plus range of motion. Significant differences in angular excursion were identified in several joints of each limb during both stance and swing phases. The most pronounced differences concerned the remaining pelvic limb, followed by the contralateral thoracic limb and, to a lesser degree, the ipsilateral thoracic limb. The thoracic limbs were, in general, more retracted, consistent with pelvic limb unloading and previous observations of bodyweight re-distribution in amputees. Proximal limb segments showed more distinct changes than distal ones. Particularly, the persistently greater anteversion of the pelvis probably affects the axial system. Overall, tripedal locomotion requires concerted kinematic adjustments of both the appendicular and axial systems, and consequently preventive, therapeutic and rehabilitative care of canine amputees should involve the whole musculoskeletal apparatus. Copyright © 2015 Elsevier Ltd. All rights reserved.

Leaping lopsided: a review of the current hypotheses regarding etiologies of limb malformations in frogs

USGS Publications Warehouse

Loeffler, I.K.; Stocum, D.L.; Fallon, J.F.; Meteyer, C.U.

2001-01-01

Recent progress in the investigation of limb malformations in free-living frogs has underlined the wide range in the types of limb malformations and the apparent spatiotemporal clustering of their occurrence. Here, we review the current understanding of normal and abnormal vertebrate limb development and regeneration and discuss some of the molecular events that may bring about limb malformation. Consideration of the differences between limb development and regeneration in amphibians has led us to the hypothesis that some of the observed limb malformations come about through misdirected regeneration. We report the results of a pilot study that supports this hypothesis. In this study, the distal aspect of the right hindlimb buds of X. laevis tadpoles was amputated at the pre-foot paddle stage. The tadpoles were raised in water from a pond in Minnesota at which 7% of surveyed newly metamorphosed feral frogs had malformations. Six percent (6 of 100) of the right limbs of the tadpoles raised in pond water developed abnormally. One truncated right limb was the only malformation in the control group, which was raised in dechlorinated municipal water. All unamputated limbs developed normally in both groups. Three major factors under consideration for effecting the limb malformations are discussed. These factors include environmental chemicals (primarily agrichemicals), encysted larvae (metacercariae) of trematode parasites, and increased levels of ultraviolet light. Emphasis is placed on the necessary intersection of environmental stressors and developmental events to bring about the specific malformations that are observed in free-living frog populations.

Society for Vascular Surgery limb stage and patient risk correlate with outcomes in an amputation prevention program.

PubMed

Causey, Marlin W; Ahmed, Ayman; Wu, Bian; Gasper, Warren J; Reyzelman, Alex; Vartanian, Shant M; Hiramoto, Jade S; Conte, Michael S

2016-06-01

Clinical decision making and accurate outcomes comparisons in advanced limb ischemia require improved staging systems. The Society for Vascular Surgery Lower Extremity Threatened Limb Classification System (Wound extent, Ischemia, and foot Infection [WIfI]) was designed to stratify limb outcomes based on three major factors-wound extent, ischemia, and foot infection. The Project or Ex-Vivo vein graft Engineering via Transfection III (PREVENT) III (PIII) risk score was developed to stratify patients by expected amputation-free survival (AFS) after surgical revascularization. This study was designed to prospectively assess limb and patient-based staging for predicting outcomes of hospitalized patients in an amputation prevention program. This study undertook a retrospective analysis of prospectively gathered registry data of consecutive patients with limb-threatening conditions admitted to a fully integrated vascular/podiatry service over a 16-month period. Upon admission, limb risk was stratified using the WIfI system and patient risk was categorized using PIII classification. Patients were assessed for perioperative and postdischarge outcomes, and their relationship to staging at admission was analyzed. There were 174 threatened limbs (143 hospitalized patients) stratified by WIfI stage (1%-12%, 2%-28%, 3%-24%, 4%-28%, 5%-3%, unstaged-5%) and PIII risk (34% low, 49% moderate, and 17% high risk). Diabetes and end-stage renal disease were associated with WIfI stage (P = .006 and P = .018) and PIII risk (P = .003 and P < .001). Perioperative (30-day) events included 3% mortality, 8% major adverse cardiovascular events and 2.4% major amputation. There were 119 limbs (71%) that underwent revascularization, including 108 infrainguinal reconstructions (endovascular or open revascularization). Rate of revascularization increased with WIfI stage (P < .001), concomitant with the number of podiatric procedures, minor amputations, and initial hospital duration of stay (all P < .001). Increased WIfI stage was associated with major adverse limb events (P = .018), reduced limb salvage (P = .037), and decreased AFS (P = .048). In contrast, PIII risk category was associated with mortality (P < .001) and AFS (P < .001). Among infrainguinal reconstruction procedures, there was a similar distribution of endovascular (46%) and surgical (54%) interventions. Freedom from major adverse limb events was best for autogenous vein bypass (P = .025), and surgical revascularization was associated with improved limb salvage among the most severely threatened limbs (WIfI stage 4: 95% limb salvage for open bypass vs 68% limb salvage for endovascular; P = .026). Among patients hospitalized with limb-threatening conditions and treated by a multidisciplinary amputation prevention team, PIII risk correlates with mortality whereas WIfI stage strongly predicts initial hospital duration of stay, and key mid-term limb outcomes. Surgical revascularization performed best in the limbs at greatest risk (WIfI stage 4), and autogenous vein bypass was the preferred conduit for open bypass. These data support the use of WIfI and PIII as complementary staging tools in the management of chronic limb-threatening ischemia. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

The Effect of Prosthetic Foot Push-off on Mechanical Loading Associated with Knee Osteoarthritis in Lower Extremity Amputees

PubMed Central

Morgenroth, David C.; Segal, Ava D.; Zelik, Karl E.; Czerniecki, Joseph M.; Klute, Glenn K.; Adamczyk, Peter G.; Orendurff, Michael S.; Hahn, Michael E.; Collins, Steven H.; Kuo, Art D.

2011-01-01

Lower extremity amputation not only limits mobility, but also increases the risk of knee osteoarthritis of the intact limb. Dynamic walking models of non-amputees suggest that pushing-off from the trailing limb can reduce collision forces on the leading limb. These collision forces may determine the peak knee external adduction moment (EAM), which has been linked to the development of knee OA in the general population. We therefore hypothesized that greater prosthetic push-off would lead to reduced loading and knee EAM of the intact limb in unilateral transtibial amputees. Seven unilateral transtibial amputees were studied during gait under three prosthetic foot conditions that were intended to vary push-off. Prosthetic foot-ankle push-off work, intact limb knee EAM and ground reaction impulses for both limbs during step-to-step transition were measured. Overall, trailing limb prosthetic push-off work was negatively correlated with leading intact limb 1st peak knee EAM (slope = −0.72 +/− 0.22; p=0.011). Prosthetic push-off work and 1st peak intact knee EAM varied significantly with foot type. The prosthetic foot condition with the least push-off demonstrated the largest knee EAM, which was reduced by 26% with the prosthetic foot producing the most push-off. Trailing prosthetic limb push-off impulse was negatively correlated with leading intact limb loading impulse (slope = −0.34 +/− 0.14; p=.001), which may help explain how prosthetic limb push-off can affect intact limb loading. Prosthetic feet that perform more prosthetic push-off appear to be associated with a reduction in 1st peak intact knee EAM, and their use could potentially reduce the risk and burden of knee osteoarthritis in this population. PMID:21803584

The effect of prosthetic foot push-off on mechanical loading associated with knee osteoarthritis in lower extremity amputees.

PubMed

Morgenroth, David C; Segal, Ava D; Zelik, Karl E; Czerniecki, Joseph M; Klute, Glenn K; Adamczyk, Peter G; Orendurff, Michael S; Hahn, Michael E; Collins, Steven H; Kuo, Art D

2011-10-01

Lower extremity amputation not only limits mobility, but also increases the risk of knee osteoarthritis of the intact limb. Dynamic walking models of non-amputees suggest that pushing-off from the trailing limb can reduce collision forces on the leading limb. These collision forces may determine the peak knee external adduction moment (EAM), which has been linked to the development of knee OA in the general population. We therefore hypothesized that greater prosthetic push-off would lead to reduced loading and knee EAM of the intact limb in unilateral transtibial amputees. Seven unilateral transtibial amputees were studied during gait under three prosthetic foot conditions that were intended to vary push-off. Prosthetic foot-ankle push-off work, intact limb knee EAM and ground reaction impulses for both limbs during step-to-step transition were measured. Overall, trailing limb prosthetic push-off work was negatively correlated with leading intact limb 1st peak knee EAM (slope=-.72±.22; p=.011). Prosthetic push-off work and 1st peak intact knee EAM varied significantly with foot type. The prosthetic foot condition with the least push-off demonstrated the largest knee EAM, which was reduced by 26% with the prosthetic foot producing the most push-off. Trailing prosthetic limb push-off impulse was negatively correlated with leading intact limb loading impulse (slope=-.34±.14; p=.001), which may help explain how prosthetic limb push-off can affect intact limb loading. Prosthetic feet that perform more prosthetic push-off appear to be associated with a reduction in 1st peak intact knee EAM, and their use could potentially reduce the risk and burden of knee osteoarthritis in this population. Published by Elsevier B.V.

The effects of body proportions on thermoregulation: an experimental assessment of Allen's rule.

PubMed

Tilkens, Michael J; Wall-Scheffler, Cara; Weaver, Timothy D; Steudel-Numbers, Karen

2007-09-01

Numerous studies have discussed the influence of thermoregulation on hominin body shape concluding, in accordance with Allen's rule, that the presence of relatively short limbs on both extant as well as extinct hominin populations offers an advantage for survival in cold climates by reducing the limb's surface area to volume ratio. Moreover, it has been suggested that shortening the distal limb segment compared to the proximal limb segment may play a larger role in thermoregulation due to a greater relative surface area of the shank. If longer limbs result in greater heat dissipation, we should see higher resting metabolic rates (RMR) in longer-limbed individuals when temperature conditions fall, since the resting rate will need to replace the lost heat. We collected resting oxygen consumption on volunteer human subjects to assess the correlation between RMR and lower limb length in human subjects, as well as to reexamine the prediction that shortening the distal segment would have a larger effect on heat loss and, thus, RMR than the shortening of the proximal segment. Total lower limb length exhibits a statistically significant relationship with resting metabolic rate (p<0.001; R(2)=0.794). While this supports the hypothesis that as limb length increases, resting metabolic rate increases, it also appears that thigh length, rather than the length of the shank, drives this relationship. The results of the present study confirm the widely-held expectation of Allen's rule, that short limbs reduce the metabolic cost of maintaining body temperature, while long limbs result in greater heat dissipation regardless of the effect of mass. The present results suggest that the shorter limbs of Neandertals, despite being energetically disadvantageous while walking, would indeed have been advantageous for thermoregulation.

The influence of asymmetric force requirements on a multi-frequency bimanual coordination task.

PubMed

Kennedy, Deanna M; Rhee, Joohyun; Jimenez, Judith; Shea, Charles H

2017-01-01

An experiment was designed to determine the impact of the force requirements on the production of bimanual 1:2 coordination patterns requiring the same (symmetric) or different (asymmetric) forces when Lissajous displays and goal templates are provided. The Lissajous displays have been shown to minimize the influence of attentional and perceptual constraints allowing constraints related to neural crosstalk to be more clearly observed. Participants (N=20) were randomly assigned to a force condition in which the left or right limb was required to produce more force than the contralateral limb. In each condition participants were required to rhythmically coordinate the pattern of isometric forces in a 1:2 coordination pattern. Participant performed 13 practice trials and 1 test trial per force level. The results indicated that participants were able to effectively coordinate the 1:2 multi-frequency goal patterns under both symmetric and asymmetric force requirements. However, consistent distortions in the force and force velocity time series were observed for one limb that appeared to be associated with the production of force in the contralateral limb. Distortions in the force produced by the left limb occurred regardless of the force requirements of the task (symmetric, asymmetric) or whether the left or right limb had to produce more force than the contralateral limb. However, distinct distortions in the right limb occurred only when the left limb was required to produce 5 times more force than the right limb. These results are consistent with the notion that neural crosstalk can influence both limbs, but may manifest differently for each limb depending on the force requirements of the task. Copyright © 2016 Elsevier B.V. All rights reserved.

Ertl and Non-Ertl amputees exhibit functional biomechanical differences during the sit-to-stand task.

PubMed

Ferris, Abbie E; Christiansen, Cory L; Heise, Gary D; Hahn, David; Smith, Jeremy D

2017-05-01

People with transtibial amputation stand ~50times/day. There are two general approaches to transtibial amputation: 1) distal tibia and fibula union using a "bone-bridge" (Ertl), 2) non-union of the tibia and fibula (Non-Ertl). The Ertl technique may improve functional outcomes by increasing the end-bearing ability of the residual limb. We hypothesized individuals with an Ertl would perform a five-time sit-to-stand task faster through greater involvement/end-bearing of the affected limb. Ertl (n=11) and Non-Ertl (n=7) participants sat on a chair with each foot on separate force plates and performed the five-time sit-to-stand task. A symmetry index (intact vs affected limbs) was calculated using peak ground reaction forces. The Ertl group performed the task significantly faster (9.33s (2.66) vs 13.27 (2.83)s). Symmetry index (23.33 (23.83)% Ertl, 36.53 (13.51)% Non-Ertl) indicated the intact limb for both groups produced more force than the affected limb. Ertl affected limb peak ground reaction forces were significantly larger than the Non-Ertl affected limb. Peak knee power and net work of the affected limb were smaller than their respective intact limb for both groups. The Ertl intact limb produced significantly greater peak knee power and net work than the Non-Ertl intact knee. Although loading asymmetries existed between the intact and affected limb of both groups, the Ertl group performed the task ~30% faster. This was driven by greater power and work production of the Ertl intact limb knee. Our results suggest that functional differences exist between the procedures. Copyright © 2017 Elsevier Ltd. All rights reserved.

Postural control strategies during single limb stance following acute lateral ankle sprain.

PubMed

Doherty, Cailbhe; Bleakley, Chris; Hertel, Jay; Caulfield, Brian; Ryan, John; Delahunt, Eamonn

2014-06-01

Single-limb stance is maintained via the integration of visual, vestibular and somatosensory afferents. Musculoskeletal injury challenges the somatosensory system to reweight distorted sensory afferents. This investigation supplements kinetic analysis of eyes-open and eyes-closed single-limb stance tasks with a kinematic profile of lower limb postural orientation in an acute lateral ankle sprain group to assess the adaptive capacity of the sensorimotor system to injury. Sixty-six participants with first-time acute lateral ankle sprain completed a 20-second eyes-open single-limb stance task on their injured and non-injured limbs (task 1). Twenty-three of these participants successfully completed the same 20-second single-limb stance task with their eyes closed (task 2). A non-injured control group of 19 participants completed task 1, with 16 completing task 2. 3-dimensional kinematics of the hip, knee and ankle joints, as well as associated fractal dimension of the center-of-pressure path were determined for each limb during these tasks. Between trial analyses revealed significant differences in stance limb kinematics and fractal dimension of the center-of-pressure path for task 2 only. The control group bilaterally assumed a position of greater hip flexion compared to injured participants on their side-matched "involved"(7.41 [6.1°] vs 1.44 [4.8]°; η(2)=.34) and "uninvolved" (9.59 [8.5°] vs 2.16 [5.6°]; η(2)=.31) limbs, with a greater fractal dimension of the center-of-pressure path (involved limb=1.39 [0.16°] vs 1.25 [0.14°]; uninvolved limb=1.37 [0.21°] vs 1.23 [0.14°]). Bilateral impairment in postural control strategies present following a first time acute lateral ankle sprain. Copyright © 2014 Elsevier Ltd. All rights reserved.

Environmental monitoring for the DOE coolside and LIMB demonstration extension projects

DOE Office of Scientific and Technical Information (OSTI.GOV)

White, T.; Contos, L.; Adams, L.

1992-02-01

The purpose of this document is to present environmental monitoring data collected during the US DOE Limestone Injection Multistage Burner (LIMB) Demonstration Project Extension. The objective of the LIMB program is to demonstrate the sulfur dioxide (SO{sub 2}) and nitrogen oxide (NO{sub x}) emission reduction capabilities of the LIMB system. The LIMB system is a retrofit technology to be used for existing coal-fired boilers equipped with electrostatic precipitators. (VC)

Tissue dielectric constant and circumference measurement in the follow-up of treatment-related changes in lower-limb lymphedema.

PubMed

Tugral, Alper; Viren, Tuomas; Bakar, Yesim

2018-02-01

Lymphedema of lower limbs is a chronic condition that requires life-long management. Therapeutic effect of complex decongestive physiotherapy (CDP) is most often followed by circumference measurements (CM). However, the CM measurements are not specific to interstitial tissue fluid and have problems in sensitivity and objectivity. The aim of present study was to evaluate the therapeutic effect of CDP with a new tissue water specific measurement technique, in patients with lower limb lymphedema (LLL). A total of 17 patients with unilateral LLL (11 primary, 6 secondary lymphedema) were recruited in this study. CDP was applied for 5 days a week for 4 weeks. CM measurement of both limbs was performed at nine sites along limb by tape measure. Percentage skin water content (PWC) of thigh, calf and ankle was measured in affected lymphedema limb and contralateral limb with MoistureMeterD Compact (MMDC) device. Inter-limb PWC ratio was calculated by dividing affected side's PWC value with PWC of contralateral limb. Patients were asked to fullfill the Lymph Quality of Life Questionnaire. Significant reduction of circumference after CDP was detected at all nine measurement sites along lower limb (P<0.01). PWC measurements showed a significant decrease of skin tissue water at thigh, calf and ankle measurement sites after CDP (P<0.001). Inter-limb PWC ratios demonstrated significant reduction of edema between affected and contraletral limbs post-treatment (P<0.003). CDP also increased the quality of life (P=0.006). CM and PWC measurements reflected a positive effect of CDP in patients with LLL. Both absolute PWC values and inter-limb PWC ratios were meaningful tools to follow the effect of therapautic intervention. Compared with CM measurements the TDC technique offered easier, quicker, objective and more practical measurements for routine assessments of LLL.

Restoring movement representation and alleviating phantom limb pain through short-term neurorehabilitation with a virtual reality system.

PubMed

Osumi, M; Ichinose, A; Sumitani, M; Wake, N; Sano, Y; Yozu, A; Kumagaya, S; Kuniyoshi, Y; Morioka, S

2017-01-01

We developed a quantitative method to measure movement representations of a phantom upper limb using a bimanual circle-line coordination task (BCT). We investigated whether short-term neurorehabilitation with a virtual reality (VR) system would restore voluntary movement representations and alleviate phantom limb pain (PLP). Eight PLP patients were enrolled. In the BCT, they repeatedly drew vertical lines using the intact hand and intended to draw circles using the phantom limb. Drawing circles mentally using the phantom limb led to the emergence of an oval transfiguration of the vertical lines ('bimanual-coupling' effect). We quantitatively measured the degree of this bimanual-coupling effect as movement representations of the phantom limb before and immediately after short-term VR neurorehabilitation. This was achieved using an 11-point numerical rating scale (NRS) for PLP intensity and the Short-Form McGill Pain Questionnaire (SF-MPQ). During VR neurorehabilitation, patients wore a head-mounted display that showed a mirror-reversed computer graphic image of an intact arm (the virtual phantom limb). By intending to move both limbs simultaneously and similarly, the patients perceived voluntary execution of movement in their phantom limb. Short-term VR neurorehabilitation promptly restored voluntary movement representations in the BCT and alleviated PLP (NRS: p = 0.015; 39.1 ± 28.4% relief, SF-MPQ: p = 0.015; 61.5 ± 48.5% relief). Restoration of phantom limb movement representations and reduced PLP intensity were linearly correlated (p < 0.05). VR rehabilitation may encourage patient's motivation and multimodal sensorimotor re-integration of a phantom limb and subsequently have a potent analgesic effect. There was no objective evidence that restoring movement representation by neurorehabilitation with virtual reality alleviated phantom limb pain. This study revealed quantitatively that restoring movement representation with virtual reality rehabilitation using a bimanual coordination task correlated with alleviation of phantom limb pain. © 2016 European Pain Federation - EFIC®.

Apparent motion perception in lower limb amputees with phantom sensations: "obstacle shunning" and "obstacle tolerance".

PubMed

Saetta, Gianluca; Grond, Ilva; Brugger, Peter; Lenggenhager, Bigna; Tsay, Anthony J; Giummarra, Melita J

2018-03-21

Phantom limbs are the phenomenal persistence of postural and sensorimotor features of an amputated limb. Although immaterial, their characteristics can be modulated by the presence of physical matter. For instance, the phantom may disappear when its phenomenal space is invaded by objects ("obstacle shunning"). Alternatively, "obstacle tolerance" occurs when the phantom is not limited by the law of impenetrability and co-exists with physical objects. Here we examined the link between this under-investigated aspect of phantom limbs and apparent motion perception. The illusion of apparent motion of human limbs involves the perception that a limb moves through or around an object, depending on the stimulus onset asynchrony (SOA) for the two images. Participants included 12 unilateral lower limb amputees matched for obstacle shunning (n = 6) and obstacle tolerance (n = 6) experiences, and 14 non-amputees. Using multilevel linear models, we replicated robust biases for short perceived trajectories for short SOA (moving through the object), and long trajectories (circumventing the object) for long SOAs in both groups. Importantly, however, amputees with obstacle shunning perceived leg stimuli to predominantly move through the object, whereas amputees with obstacle tolerance perceived leg stimuli to predominantly move around the object. That is, in people who experience obstacle shunning, apparent motion perception of lower limbs was not constrained to the laws of impenetrability (as the phantom disappears when invaded by objects), and legs can therefore move through physical objects. Amputees who experience obstacle tolerance, however, had stronger solidity constraints for lower limb apparent motion, perhaps because they must avoid co-location of the phantom with physical objects. Phantom limb experience does, therefore, appear to be modulated by intuitive physics, but not in the same way for everyone. This may have important implications for limb experience post-amputation (e.g., improving prosthesis embodiment when limb representation is constrained by the same limits as an intact limb). Copyright © 2018 Elsevier Ltd. All rights reserved.

Medial knee joint contact force in the intact limb during walking in recently ambulatory service members with unilateral limb loss: a cross-sectional study

PubMed Central

Krupenevich, Rebecca L.; Pruziner, Alison L.; Wolf, Erik J.; Schnall, Barri L.

2017-01-01

Background Individuals with unilateral lower limb amputation have a high risk of developing knee osteoarthritis (OA) in their intact limb as they age. This risk may be related to joint loading experienced earlier in life. We hypothesized that loading during walking would be greater in the intact limb of young US military service members with limb loss than in controls with no limb loss. Methods Cross-sectional instrumented gait analysis at self-selected walking speeds with a limb loss group (N = 10, age 27 ± 5 years, 170 ± 36 days since last surgery) including five service members with transtibial limb loss and five with transfemoral limb loss, all walking independently with their first prosthesis for approximately two months. Controls (N = 10, age 30 ± 4 years) were service members with no overt demographical risk factors for knee OA. 3D inverse dynamics modeling was performed to calculate joint moments and medial knee joint contact forces (JCF) were calculated using a reduction-based musculoskeletal modeling method and expressed relative to body weight (BW). Results Peak JCF and maximum JCF loading rate were significantly greater in limb loss (184% BW, 2,469% BW/s) vs. controls (157% BW, 1,985% BW/s), with large effect sizes. Results were robust to probabilistic perturbations to the knee model parameters. Discussion Assuming these data are reflective of joint loading experienced in daily life, they support a “mechanical overloading” hypothesis for the risk of developing knee OA in the intact limb of limb loss subjects. Examination of the evolution of gait mechanics, joint loading, and joint health over time, as well as interventions to reduce load or strengthen the ability of the joint to withstand loads, is warranted. PMID:28168120

Imparting regenerative capacity to limbs by progenitor cell transplantation

PubMed Central

Lin, Gufa; Chen, Ying; Slack, Jonathan M.W.

2012-01-01

Summary The frog Xenopus can normally regenerate its limbs at early developmental stages but loses the ability during metamorphosis. This behavior provides a potential gain-of-function model for measures that can enhance limb regeneration. Here we show that frog limbs can be caused to form multidigit regenerates after receiving transplants of larval limb progenitor cells. It is necessary to activate Wnt/β -catenin signaling in the cells, and to add Sonic hedgehog, FGF10 and thymosin β4. These factors promote survival and growth of the grafted cells and also provide pattern information. The eventual regenerates are not composed solely of donor tissue; the host cells also make a substantial contribution despite their lack of regeneration-competence. Cells from adult frog legs or from regenerating tadpole tails do not promote limb regeneration, demonstrating the necessity for limb progenitor cells. These findings have obvious implications for the development of a technology to promote limb regeneration in mammals. PMID:23273877

The Dependence of Solar Flare Limb Darkening on Emission Peak Formation Temperature

NASA Astrophysics Data System (ADS)

Thiemann, Edward; Epp, Luke; Eparvier, Francis; Chamberlin, Phillip C.

2017-08-01

Solar limb effects are local brightening or darkening of an emission that depend on where in the Sun's atmosphere it forms. Near the solar limb, optically thick (thin) emissions will darken (brighten) as the column of absorbers (emitters) along the line-of-sight increases. Note that in limb brightening, emission sources are re-arranged whereas in limb darkening they are obscured. Thus, only limb darkening is expected to occur in disk integrated observations. Limb darkening also results in center-to-limb variations of disk-integrated solar flare spectra, with important consequences for how planetary atmospheres are affected by flares. Flares are typically characterized by their flux in the optically thin 0.1-0.8 nm band measured by the X-ray Sensor (XRS) on board the Geostationary Operational Environmental Satellite (GOES). On the other hand, Extreme Ultraviolet (EUV) line emissions can limb darken because they are sensitive to resonant scattering, resulting in a flare's location on the solar disk controlling the amount of ionizing radiation that reaches a planet. For example, an X-class flare originating from disk center may significantly heat a planet's thermosphere, whereas the same flare originating near the limb may have no effect because much of the effective emissions are scattered in the solar corona.To advance the relatively poor understanding of flare limb darkening, we use over 300 M-class or larger flares observed by the EUV Variability Experiment (EVE) onboard the Solar Dynamics Observatory (SDO) to characterize limb darkening as a function of emission peak formation temperature, Tf. For hot coronal emissions (Tf>2 MK), these results show a linear relationship between the degree of limb darkening and Tf where lines with Tf=2 MK darken approximately 7 times more than lines with Tf=16 MK. Because the extent of limb darkening is dependent on the height of the source plasma, we use simple Beer-Lambert radiative transfer analysis to interpret these results and characterize the average thermal structure of the flares considered. As such, these results can be used to constrain both empirical flare irradiance models and more sophisticated flare loop hydrodynamic models.

The solar XUV He I and He II emission lines. I - Intensities and gross center-to-limb behavior

NASA Technical Reports Server (NTRS)

Mango, S. A.; Bohlin, J. D.; Glackin, D. L.; Linsky, J. L.

1978-01-01

The center-to-limb variation of the He II 304- and 256-A lines and He I 584- and 537-A lines is derived for different solar features, but averaged over the chromospheric supergranulation structure. The general trend is for limb brightening in quiet-sun regions, limb neutrality in unipolar magnetic regions (UMR), and limb darkening in polar coronal holes. The center-to-limb behavior in these optically thick emission lines indicates collisional excitation and decreasing transition-region temperature gradients with respect to optical depth in the sequence quiet sun to UMR to coronal hole.

Positional information in axolotl and mouse limb extracellular matrix is mediated via heparan sulfate and fibroblast growth factor during limb regeneration in the axolotl (Ambystoma mexicanum).

PubMed

Phan, Anne Q; Lee, Jangwoo; Oei, Michelle; Flath, Craig; Hwe, Caitlyn; Mariano, Rachele; Vu, Tiffany; Shu, Cynthia; Dinh, Andrew; Simkin, Jennifer; Muneoka, Ken; Bryant, Susan V; Gardiner, David M

2015-08-01

Urodele amphibians are unique among adult vertebrates in their ability to regenerate complex body structures after traumatic injury. In salamander regeneration, the cells maintain a memory of their original position and use this positional information to recreate the missing pattern. We used an in vivo gain-of-function assay to determine whether components of the extracellular matrix (ECM) have positional information required to induce formation of new limb pattern during regeneration. We discovered that salamander limb ECM has a position-specific ability to either inhibit regeneration or induce de novo limb structure, and that this difference is dependent on heparan sulfates that are associated with differential expression of heparan sulfate sulfotransferases. We also discovered that an artificial ECM containing only heparan sulfate was sufficient to induce de novo limb pattern in salamander limb regeneration. Finally, ECM from mouse limbs is capable of inducing limb pattern in axolotl blastemas in a position-specific, developmental-stage-specific, and heparan sulfate-dependent manner. This study demonstrates a mechanism for positional information in regeneration and establishes a crucial functional link between salamander regeneration and mammals.

Positional information in axolotl and mouse limb extracellular matrix is mediated via heparan sulfate and fibroblast growth factor during limb regeneration in the axolotl (Ambystoma mexicanum)

PubMed Central

Phan, Anne Q.; Lee, Jangwoo; Oei, Michelle; Flath, Craig; Hwe, Caitlyn; Mariano, Rachele; Vu, Tiffany; Shu, Cynthia; Dinh, Andrew; Simkin, Jennifer; Muneoka, Ken; Bryant, Susan V.

2015-01-01

Abstract Urodele amphibians are unique among adult vertebrates in their ability to regenerate complex body structures after traumatic injury. In salamander regeneration, the cells maintain a memory of their original position and use this positional information to recreate the missing pattern. We used an in vivo gain‐of‐function assay to determine whether components of the extracellular matrix (ECM) have positional information required to induce formation of new limb pattern during regeneration. We discovered that salamander limb ECM has a position‐specific ability to either inhibit regeneration or induce de novo limb structure, and that this difference is dependent on heparan sulfates that are associated with differential expression of heparan sulfate sulfotransferases. We also discovered that an artificial ECM containing only heparan sulfate was sufficient to induce de novo limb pattern in salamander limb regeneration. Finally, ECM from mouse limbs is capable of inducing limb pattern in axolotl blastemas in a position‐specific, developmental‐stage‐specific, and heparan sulfate‐dependent manner. This study demonstrates a mechanism for positional information in regeneration and establishes a crucial functional link between salamander regeneration and mammals. PMID:27499874

HOW DOES ADDING AND REMOVING LIQUID FROM SOCKET BLADDERS AFFECT RESIDUAL LIMB FLUID VOLUME?

PubMed Central

Sanders, JE; Cagle, JC; Harrison, DS; Myers, TR; Allyn, KJ

2015-01-01

Adding and removing liquid from socket bladders is a means for people with limb loss to accommodate residual limb volume change. Nineteen people with trans-tibial amputation using their regular prosthetic socket fitted with fluid bladders on the inside socket surface underwent cycles of bladder liquid addition and removal. In each cycle, subjects sat, stood, and walked for 90s with bladder liquid added and then sat, stood, and walking for 90s again with the bladder liquid removed. The amount of bladder liquid added was increased in each cycle. Bioimpedance analysis was implemented to measure residual limb fluid volume. Results showed that the preferred bladder liquid volume was 16.8 mL (s.d.8.4), corresponding to 1.7% (s.d.0.8%) of the average socket volume between the bioimpedance voltage-sensing electrodes. Limb fluid volume driven out of the residual limb when bladder liquid was added was typically not recovered upon subsequent bladder liquid removal. Fifteen of nineteen subjects experienced a gradual limb fluid volume loss over the test session. Care should be taken when implementing adjustable socket technologies in people with limb amputation. Reducing socket volume may accentuate limb fluid volume loss. PMID:24203546

Limb Correction of Polar-Orbiting Imagery for the Improved Interpretation of RGB Composites

NASA Technical Reports Server (NTRS)

Jedlovec, Gary J.; Elmer, Nicholas

2016-01-01

Red-Green-Blue (RGB) composite imagery combines information from several spectral channels into one image to aid in the operational analysis of atmospheric processes. However, infrared channels are adversely affected by the limb effect, the result of an increase in optical path length of the absorbing atmosphere between the satellite and the earth as viewing zenith angle increases. This paper reviews a newly developed technique to quickly correct for limb effects in both clear and cloudy regions using latitudinally and seasonally varying limb correction coefficients for real-time applications. These limb correction coefficients account for the increase in optical path length in order to produce limb-corrected RGB composites. The improved utility of a limb-corrected Air Mass RGB composite from the application of this approach is demonstrated using Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) imagery. However, the limb correction can be applied to any polar-orbiting sensor infrared channels, provided the proper limb correction coefficients are calculated. Corrected RGB composites provide multiple advantages over uncorrected RGB composites, including increased confidence in the interpretation of RGB features, improved situational awareness for operational forecasters, and the ability to use RGB composites from multiple sensors jointly to increase the temporal frequency of observations.

Chemical activation of Wnt/β-catenin signalling inhibits innervation and causes skeletal tissue malformations during axolotl limb regeneration.

PubMed

Wischin, Sabina; Castañeda-Patlán, Cristina; Robles-Flores, Martha; Chimal-Monroy, Jesús

2017-04-01

Limb regeneration involves several interrelated physiological processes in which a particular signalling pathway may play a variety of functions. Blocking the function of Wnt/β-catenin signalling during limb regeneration inhibits regeneration in axolotls (Ambystoma mexicanum). Limb development shares many features with limb regeneration, and Wnt/β-catenin activation has different effects depending on the developmental stage. The aim of this study was to evaluate whether Wnt/β-catenin signalling activation during axolotl limb regeneration has different effects when activated at different stages of regeneration. To evaluate this hypothesis, we treated amputated axolotls with a Wnt agonist chemical at different stages of limb regeneration. The results showed that limb regeneration was inhibited when the treatment began before blastema formation. Under these conditions, blastema formation was hindered, possibly due to the lack of innervation. On the other hand, when axolotls were treated after blastema formation and immediately before the onset of morphogenesis, we observed structural disorganization in skeletal formation. In conclusion, we found that limb regeneration was differentially affected depending on the stage at which the Wnt signalling pathway was activated. Copyright © 2017 Elsevier B.V. All rights reserved.

Detection of Genes Regulated by Lmx1b During Limb Dorsalization

PubMed Central

Feenstra, Jennifer M.; Kanaya, Kohei; Pira, Charmaine U; Hoffman, Sarah E.; Eppey, Richard J.; Oberg, Kerby C.

2012-01-01

Lmx1b is a homeodomain transcription factor that regulates dorsal identity during limb development. Lmx1b knockout (KO) mice develop distal ventral-ventral limbs. Although induction of Lmx1b is linked to Wnt7a expression in the dorsal limb ectoderm, the downstream targets of Lmx1b that accomplish limb dorsalization are unknown. To identify genes targeted by Lmx1b, we compared gene arrays from Lmx1b KO and wildtype mouse limbs during limb dorsalization, i.e., 11.5, 12.5, and 13.5 days post coitum. We identified 54 target genes differentially expressed in all three stages. Several skeletal targets, including Emx2, Matrilin1 and Matrilin4, demonstrated a loss of scapular expression in the Lmx1b KO mice, supporting a role for Lmx1b in scapula development. Furthermore, the relative abundance of extracellular matrix-related soft tissue targets regulated by Lmx1b, such as collagens and proteoglycans, suggests a mechanism which includes changes in the extracellular matrix composition to accomplish limb dorsalization. Our study provides the most comprehensive characterization of genes regulated by Lmx1b during limb development to-date and provides targets for further investigation. PMID:22417325

CRISM Limb Observations of Aerosols and Water Vapor

NASA Technical Reports Server (NTRS)

Smith, Michael D.; Wolff, M.J.; Clancy, R.T.; Seelos, F.; Murchie, S.L.

2009-01-01

Near-infrared spectra taken in a limb-viewing geometry by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) on-board the Mars Reconnaissance Orbiter (MRO) provide a useful tool for probing atmospheric structure. Here we describe preliminary work on the retrieval of vertical profiles of aerosols and water vapor from the CRISM limb observations. The first full set of CRISM limb observations was taken in July 2009, with subsequent limb observations planned once every two months. Each set of limb observations contains about four dozen scans across the limb giving pole-to-pole coverage for two orbits at roughly 100 and 290 W longitude. Radiative transfer modeling taking account of aerosol scattering in the limb-viewing geometry is used to model the observations. The retrievals show the height to which dust and water vapor extend and the location and height of water ice clouds. Results from the First set of CRISM limb observations (July 2009, Ls=300) show dust aerosol well-mixed to about three scale heights above the surface with thin water ice clouds above the dust near the equator and at mid-northern latitudes. Water vapor is concentrated at high southern latitudes.

Neural mechanisms of limb position estimation in the primate brain.

PubMed

Shi, Ying; Buneo, Christopher A

2011-01-01

Understanding the neural mechanisms of limb position estimation is important both for comprehending the neural control of goal directed arm movements and for developing neuroprosthetic systems designed to replace lost limb function. Here we examined the role of area 5 of the posterior parietal cortex in estimating limb position based on visual and somatic (proprioceptive, efference copy) signals. Single unit recordings were obtained as monkeys reached to visual targets presented in a semi-immersive virtual reality environment. On half of the trials animals were required to maintain their limb position at these targets while receiving both visual and non-visual feedback of their arm position, while on the other trials visual feedback was withheld. When examined individually, many area 5 neurons were tuned to the position of the limb in the workspace but very few neurons modulated their firing rates based on the presence/absence of visual feedback. At the population level however decoding of limb position was somewhat more accurate when visual feedback was provided. These findings support a role for area 5 in limb position estimation but also suggest that visual signals regarding limb position are only weakly represented in this area, and only at the population level.

Intralimb and Interlimb Cutaneous Reflexes during Locomotion in the Intact Cat.

PubMed

Hurteau, Marie-France; Thibaudier, Yann; Dambreville, Charline; Danner, Simon M; Rybak, Ilya A; Frigon, Alain

2018-04-25

When the foot contacts an obstacle during locomotion, cutaneous inputs activate spinal circuits to ensure dynamic balance and forward progression. In quadrupeds, this requires coordinated reflex responses between the four limbs. Here, we investigated the patterns and phasic modulation of cutaneous reflexes in forelimb and hindlimb muscles evoked by inputs from all four limbs. Five female cats were implanted to record muscle activity and to stimulate the superficial peroneal and superficial radial nerves during locomotion. Stimulating these nerves evoked short-, mid-, and longer-latency excitatory and/or inhibitory responses in all four limbs that were phase-dependent. The largest responses were generally observed during the peak activity of the muscle. Cutaneous reflexes during mid-swing were consistent with flexion of the homonymous limb and accompanied by modification of the stance phases of the other three limbs, by coactivating flexors and extensors and/or by delaying push-off. Cutaneous reflexes during mid-stance were consistent with stabilizing the homonymous limb by delaying and then facilitating its push-off and modifying the support phases of the homolateral and diagonal limbs, characterized by coactivating flexors and extensors, reinforcing extensor activity and/or delaying push-off. The shortest latencies of homolateral and diagonal responses were consistent with fast-conducting disynaptic or trisynaptic pathways. Descending homolateral and diagonal pathways from the forelimbs to the hindlimbs had a higher probability of eliciting responses compared with ascending pathways from the hindlimbs to the forelimbs. Thus, in quadrupeds, intralimb and interlimb reflexes activated by cutaneous inputs ensure dynamic coordination of the four limbs, producing a whole-body response. SIGNIFICANCE STATEMENT The skin contains receptors that, when activated, send inputs to spinal circuits, signaling a perturbation. Rapid responses, or reflexes, in muscles of the contacted limb and opposite homologous limb help maintain balance and forward progression. Here, we investigated reflexes during quadrupedal locomotion in the cat by electrically stimulating cutaneous nerves in each of the four limbs. Functionally, responses appear to modify the trajectory or stabilize the movement of the stimulated limb while modifying the support phase of the other limbs. Reflexes between limbs are mediated by fast-conducting pathways that involve excitatory and inhibitory circuits controlling each limb. The comparatively stronger descending pathways from cervical to lumbar circuits controlling the forelimbs and hindlimbs, respectively, could serve a protective function. Copyright © 2018 the authors 0270-6474/18/384104-19$15.00/0.

Muscular and functional effects of partitioning exercising muscle mass in patients with chronic obstructive pulmonary disease - a study protocol for a randomized controlled trial.

PubMed

Nyberg, Andrè; Saey, Didier; Martin, Mickaël; Maltais, François

2015-04-27

Low-load, high-repetitive single-limb resistance training may increase limb muscle function and functional exercise capacity in patients with chronic obstructive pulmonary disease (COPD) while minimizing the occurrence of limiting exertional symptoms. Whether high-repetitive single-limb resistance training would perform better than high-repetitive two-limb resistance training is unknown. In addition, the mechanisms underlying possible benefits of high-repetitive resistance training has not been investigated. The aims of this study are to compare single versus two-limb high-repetitive resistance training in patients with COPD and to investigate mechanisms of action of these training modalities. This trial is a prospective, assessor-blind, randomized controlled trial. The participants are patients with stable severe to very severe COPD who are older than 40 years of age and healthy controls. The intervention is single-limb, high-repetitive, resistance training with elastic bands, three times/week for 8 weeks. The control is two-limb high-repetitive resistance training with elastic bands, three times/week for 8 weeks. The primary outcomes is change in the 6-min walking distance after 8 weeks of single-limb or two-limb high-repetitive resistance training. The secondary outcomes are changes in limb muscle strength and endurance capacity, key protein involved in quadriceps anabolic/catabolic signalization, fiber-type distribution and capillarization, subjective dyspnea and muscle fatigue, muscle oxygenation, cardiorespiratory demand and health-related quality-of-life after 8 weeks of single-limb or two-limb high-repetitive resistance training. The acute effects of single-limb versus two-limb high-repetitive resistance training on contractile fatigue, exercise stimulus (the product of number of repetition and load), subjective dyspnea and muscle fatigue, muscle oxygenation, and cardiorespiratory demand during upper and lower limb exercises will also be investigated in patients with COPD and healthy controls. Randomization will be performed using a random number generator by a person independent of the recruitment process, using 1:1 allocation to the intervention and the control group using random block sizes. All outcome assessors will be blinded to group assignment. The results of this project will provide important information to help developing and implementing customized exercise training programs for patients with COPD. ClinicalTrials.gov Identifier NCT02283580 Registration date: 4 November 2014. First participant randomized: 10 November 2014.

Functional anatomy and muscle moment arms of the thoracic limb of an elite sprinting athlete: the racing greyhound (Canis familiaris)

PubMed Central

Williams, S B; Wilson, A M; Daynes, J; Peckham, K; Payne, R C

2008-01-01

We provide quantitative muscle–tendon architecture and geometry data for the racing greyhound thoracic limb. Muscle mass, belly length, fascicle lengths, pennation angles and moment arms were measured, as were tendon masses and lengths. Maximum isometric force and maximum power were estimated for muscles, and maximum stress and strain were estimated for tendons. Results are compared with other fast quadrupedal runners, and to previously published data in mixed-breed dogs. The implications of the functional adaptations of the greyhound thoracic limb for sprinting performance are discussed. The thoracic limb was found to benefit from a similar proportion of locomotor muscle mass to the pelvic limb, suggesting that it may be used to some extent in propulsion, or alternatively that stabilisation is very important in this animal. Extrinsic muscles, especially latissimus dorsi and pectoralis profundus, were predicted to be powerful and important for generating net positive work during accelerations. Proximal biarticular muscles show specialisation toward preventing collapse of the shoulder and elbow joints to enable strut-like limb function, or some form of dynamic control. Distal muscles did not appear specialised for elastic energy storage, a functional difference to pelvic limb muscles, and the equivalents in horse thoracic limbs. The greyhound thoracic limb appears to possess substantial differences from both that of more ‘sub-maximal specialist’ quadrupeds, and from the greyhound pelvic limb. PMID:19034998

Functional anatomy and muscle moment arms of the thoracic limb of an elite sprinting athlete: the racing greyhound (Canis familiaris).

PubMed

Williams, S B; Wilson, A M; Daynes, J; Peckham, K; Payne, R C

2008-10-01

We provide quantitative muscle-tendon architecture and geometry data for the racing greyhound thoracic limb. Muscle mass, belly length, fascicle lengths, pennation angles and moment arms were measured, as were tendon masses and lengths. Maximum isometric force and maximum power were estimated for muscles, and maximum stress and strain were estimated for tendons. Results are compared with other fast quadrupedal runners, and to previously published data in mixed-breed dogs. The implications of the functional adaptations of the greyhound thoracic limb for sprinting performance are discussed. The thoracic limb was found to benefit from a similar proportion of locomotor muscle mass to the pelvic limb, suggesting that it may be used to some extent in propulsion, or alternatively that stabilisation is very important in this animal. Extrinsic muscles, especially latissimus dorsi and pectoralis profundus, were predicted to be powerful and important for generating net positive work during accelerations. Proximal biarticular muscles show specialisation toward preventing collapse of the shoulder and elbow joints to enable strut-like limb function, or some form of dynamic control. Distal muscles did not appear specialised for elastic energy storage, a functional difference to pelvic limb muscles, and the equivalents in horse thoracic limbs. The greyhound thoracic limb appears to possess substantial differences from both that of more 'sub-maximal specialist' quadrupeds, and from the greyhound pelvic limb.

Allometry and apparent paradoxes in human limb proportions: Implications for scaling factors.

PubMed

Auerbach, Benjamin M; Sylvester, Adam D

2011-03-01

It has been consistently demonstrated that human proximal limb elements exhibit negative allometry, while distal elements scale with positive allometry. Such scaling implies that longer limbs will have higher intralimb indices, a phenomenon not borne out by empirical analyses. This, therefore, creates a paradox within the limb allometry literature. This study shows that these apparently conflicting results are the product of two separate phenomena. First, the use of the geometric mean of limb elements produces allometry coefficients that are not independent, and that when using ordinary least squares regression must yield an average slope of one. This phenomenon argues against using the geometric mean as a size variable when examining limb allometry. While the employment of relevant dimensions independent of those under analysis to calculate the geometric mean--as suggested by Coleman (Am J Phys Anthropol 135 (2008) 404-415)--may be a partial method for resolving the problem, an empirically determined, independent and biologically relevant size variable is advocated. If stature is used instead of the geometric mean as an independent size variable, all major limb elements scale with positive allometry. Second, while limb allometry coefficients do indicate differential allometry in limb elements, and thus should lead to some intralimb index allometry, this pattern appears to be attenuated by other sources of limb element length variation. Copyright © 2010 Wiley-Liss, Inc.

Experimental evaluation of rigor mortis. III. Comparative study of the evolution of rigor mortis in different sized muscle groups in rats.

PubMed

Krompecher, T; Fryc, O

1978-01-01

The use of new methods and an appropriate apparatus has allowed us to make successive measurements of rigor mortis and a study of its evolution in the rat. By a comparative examination on the front and hind limbs, we have determined the following: (1) The muscular mass of the hind limbs is 2.89 times greater than that of the front limbs. (2) In the initial phase rigor mortis is more pronounced in the front limbs. (3) The front and hind limbs reach maximum rigor mortis at the same time and this state is maintained for 2 hours. (4) Resolution of rigor mortis is accelerated in the front limbs during the initial phase, but both front and hind limbs reach complete resolution at the same time.

Expression of Msx-2 during development, regeneration, and wound healing in axolotl limbs.

PubMed

Carlson, M R; Bryant, S V; Gardiner, D M

1998-12-15

Msx genes are transcription factors that are expressed during embryogenesis of developing appendages in regions of epithelial-mesenchymal interactions. Various lines of evidence indicate that these genes function to maintain embryonic tissues in an undifferentiated, proliferative state. We have identified the axolotl homolog of Msx-2, and investigated its expression during limb development, limb regeneration, and wound healing. As in limb buds of higher vertebrates, axolotl Msx-2 is expressed in the apical epidermis and mesenchyme; however, its expression domain is more extensive, reflecting the broader region of the apical epidermal cap in amphibians. Msx-2 expression is downregulated at late stages of limb development, but is reexpressed within one hour after limb amputation. Msx-2 is also reexpressed during wound healing, and may be essential in the early stages of initiation of the limb regeneration cascade.

Phantom Limbs, Neuroprosthetics, and the Developmental Origins of Embodiment.

PubMed

Blumberg, Mark S; Dooley, James C

2017-10-01

Amputees who wish to rid themselves of a phantom limb must weaken the neural representation of the absent limb. Conversely, amputees who wish to replace a lost limb must assimilate a neuroprosthetic with the existing neural representation. Whether we wish to remove a phantom limb or assimilate a synthetic one, we will benefit from knowing more about the developmental process that enables embodiment. A potentially critical contributor to that process is the spontaneous activity - in the form of limb twitches - that occurs exclusively and abundantly during active (REM) sleep, a particularly prominent state in early development. The sensorimotor circuits activated by twitching limbs, and the developmental context in which activation occurs, could provide a roadmap for creating neuroprosthetics that feel as if they are part of the body. Copyright © 2017 Elsevier Ltd. All rights reserved.

Growth characteristics of fibroblasts isolated from the trunk and distal aspect of the limb of horses and ponies.

PubMed

Miller, C B; Wilson, D A; Keegan, K G; Kreeger, J M; Adelstein, E H; Ganjam, V K

2000-01-01

To determine if there is a difference in in vitro growth of fibroblasts isolated from the trunk and distal aspect of the limb of horses and ponies. To determine the effects of a corticosteroid and monokine on in vitro growth of fibroblasts isolated from the trunk and distal aspect of the limb of horses and ponies. Growth of fibroblasts from tissues harvested from the trunk and limb were compared from horse and pony samples grown in control media and control media with triamcinolone or monokine added. Dermal and subcutaneous tissue from 22 horses and 17 ponies of various ages and breeds. Fibroblast growth was assessed by tritiated thymidine uptake using standard cell culture techniques. The effect of a monokine or triamcinolone plus control media were compared with control media for fibroblast growth. Fibroblast growth from tissues isolated from the horse limb was significantly less than growth from the horse trunk and the limb and trunk of ponies. Monokine was more effective than triamcinolone in suppressing fibroblast growth from tissues isolated from the trunk and limb in both horses and ponies. There are growth differences in fibroblasts isolated from the limb of horses compared with those isolated from the trunk and from the limb and trunk of ponies. The difference in fibroblast growth from tissues isolated from the trunk and limb of horses and ponies may provide evidence for the difference reported in the healing characteristics of limb wounds in horses and ponies. Influencing fibroblast growth may provide a key to controlling the development of exuberant granulation tissue in horses and ponies.

The Differential Effect of Arm Movements during Gait on the Forward Acceleration of the Centre of Mass in Children with Cerebral Palsy and Typically Developing Children.

PubMed

Meyns, Pieter; Molenaers, Guy; Duysens, Jacques; Jonkers, Ilse

2017-01-01

Background: We aimed to study the contribution of upper limb movements to propulsion during walking in typically developing (TD) children ( n = 5) and children with hemiplegic and diplegic cerebral palsy (CP; n = 5 and n = 4, respectively). Methods: Using integrated three-dimensional motion capture data and a scaled generic musculoskeletal model that included upper limbs, we generated torque driven simulations of gait in OpenSim. Induced acceleration analyses were then used to determine the contributions of the individual actuators located at the relevant degrees of freedoms of the upper and lower limb joints to the forward acceleration of the COM at each time point of the gait simulation. The mean values of the contribution of the actuators of upper limbs, lower limbs, and gravity in different phases of the gait cycle were compared between the three groups. Findings: The results indicated a limited contribution of the upper limb actuators to COM forward acceleration compared to the contribution of lower limbs and gravity, in the three groups. In diplegic CP, the contribution of the upper limbs seemed larger compared to TD during the preswing and swing phases of gait. In hemiplegic CP, the unaffected arm seemed to contribute more to COM deceleration during (pre)swing, while the affected side contributed to COM acceleration. Interpretation: These findings suggest that in the presence of lower limb dysfunction, the contribution of the upper limbs to forward propulsion is altered, although they remain negligible compared to the lower limbs and gravity.

Comparison of transtibial amputee and non-amputee biomechanics during a common turning task.

PubMed

Segal, Ava D; Orendurff, Michael S; Czerniecki, Joseph M; Schoen, Jason; Klute, Glenn K

2011-01-01

The biomechanics of amputee turning gait has been minimally studied, in spite of its integral relationship with the more complex gait required for household or community ambulation. This study compares the biomechanics of unilateral transtibial amputees and non-amputees completing a common turning task. Full body gait analysis was completed for subjects walking at comparable self-selected speeds around a 1m radius circular path. Peak internal and external rotation moments of the hip, knee and ankle, mediolateral ground reaction impulse (ML GRI), peak effective limb length, and stride length were compared across conditions (non-amputee, amputee prosthetic limb, amputee sound limb). Amputees showed decreased internal rotation moments at the prosthetic limb hip and knee compared to non-amputees, perhaps as a protective mechanism to minimize stress on the residual limb. There was also an increase in amputee sound limb hip external rotation moment in early stance compared to non-amputees, which may be a compensation for the decrease in prosthetic limb internal rotation moment during late stance of the prior step. ML GRI was decreased for the amputee inside limb compared to non-amputee, possibly to minimize the body's acceleration in the direction of the turn. Amputees also exhibited a shorter inside limb stride length compared to non-amputees. Both decreased ML GRI and stride length indicate a COM that is more centered over the base of support, which may minimize the risk of falling. Finally, a longer effective limb length was found for the amputee inside limb turning, possibly due to excessive trunk shift. Published by Elsevier B.V.

Objective assessment of the compensatory effect of clinical hind limb lameness in horses: 37 cases (2011-2014).

PubMed

Maliye, Sylvia; Marshall, John F

2016-10-15

OBJECTIVE To characterize and describe the compensatory load redistribution that results from unilateral hind limb lameness in horses. DESIGN Retrospective case series. ANIMALS 37 client-owned horses. PROCEDURES Medical records were reviewed to identify horses with unilateral hind limb lameness that responded positively (by objective assessment) to diagnostic local anesthesia during lameness evaluation and that were evaluated before and after diagnostic local anesthesia with an inertial sensor-based lameness diagnosis system. Horses were grouped as having hind limb lameness only, hind limb and ipsilateral forelimb lameness, or hind limb and contralateral forelimb lameness. Measures of head and pelvic movement asymmetry before (baseline) and after diagnostic local anesthesia were compared. The effect of group on baseline pelvic movement asymmetry variables was analyzed statistically. RESULTS Maximum pelvic height significantly decreased from the baseline value after diagnostic local anesthesia in each of the 3 lameness groups and in all horses combined. Minimum pelvic height significantly decreased after the procedure in all groups except the hind limb and contralateral forelimb lameness group. Head movement asymmetry was significantly decreased after diagnostic local anesthesia for horses with hind limb and ipsilateral forelimb lameness and for all horses combined, but not for those with hind limb lameness only or those with hind limb and contralateral forelimb lameness. CONCLUSIONS AND CLINICAL RELEVANCE Results supported that hind limb lameness can cause compensatory load redistribution evidenced as ipsilateral forelimb lameness. In this population of horses, contralateral forelimb lameness was not compensatory and likely reflected true lameness. Further studies are needed to investigate the source of the contralateral forelimb lameness in such horses.

Lower-Limb Amputation and Effect of Posttraumatic Stress Disorder on Department of Veterans Affairs Outpatient Cost Trends

DTIC Science & Technology

2015-07-01

JRRD Volume 52, Number 7, 2015Pages 827–838Lower-limb amputation and effect of posttraumatic stress disorder on Department of Veterans Affairs...lower- limb amputations and limb injuries. We evaluated the effect of lower-limb injury, amputation(s), and PTSD on outpatient costs, adjusting for...amputation status and significant parameters were tested (p  0.05) and models stratified by significant effect modi- fiers (p  0.05). For cost categories

Environmental monitoring for the DOE coolside and LIMB demonstration extension projects. Quarterly report for the period of February, March and April 1991

DOE Office of Scientific and Technical Information (OSTI.GOV)

White, T.; Contos, L.; Adams, L.

1992-02-01

The purpose of this document is to present environmental monitoring data collected during the US DOE Limestone Injection Multistage Burner (LIMB) Demonstration Project Extension. The objective of the LIMB program is to demonstrate the sulfur dioxide (SO{sub 2}) and nitrogen oxide (NO{sub x}) emission reduction capabilities of the LIMB system. The LIMB system is a retrofit technology to be used for existing coal-fired boilers equipped with electrostatic precipitators. (VC)

Lineage tracing of genome-edited alleles reveals high fidelity axolotl limb regeneration.

PubMed

Flowers, Grant Parker; Sanor, Lucas D; Crews, Craig M

2017-09-16

Salamanders are unparalleled among tetrapods in their ability to regenerate many structures, including entire limbs, and the study of this ability may provide insights into human regenerative therapies. The complex structure of the limb poses challenges to the investigation of the cellular and molecular basis of its regeneration. Using CRISPR/Cas, we genetically labelled unique cell lineages within the developing axolotl embryo and tracked the frequency of each lineage within amputated and fully regenerated limbs. This allowed us, for the first time, to assess the contributions of multiple low frequency cell lineages to the regenerating limb at once. Our comparisons reveal that regenerated limbs are high fidelity replicas of the originals even after repeated amputations.

Disappearance of "phantom limb" and amputated arm usage during dreaming in REM sleep behaviour disorder.

PubMed

Vetrugno, Roberto; Arnulf, Isabelle; Montagna, Pasquale

2009-01-01

Limb amputation is followed, in approximately 90% of patients, by "phantom limb" sensations during wakefulness. When amputated patients dream, however, the phantom limb may be present all the time, part of the time, intermittently or not at all. Such dreaming experiences in amputees have usually been obtained only retrospectively in the morning and, moreover, dreaming is normally associated with muscular atonia so the motor counterpart of the phantom limb experience cannot be observed directly. REM sleep behaviour disorder (RBD), in which muscle atonia is absent during REM sleep and patients act out their dreams, allows a more direct analysis of the "phantom limb" phenomena and their modifications during sleep.

Robotics in Lower-Limb Rehabilitation after Stroke

PubMed Central

2017-01-01

With the increase in the elderly, stroke has become a common disease, often leading to motor dysfunction and even permanent disability. Lower-limb rehabilitation robots can help patients to carry out reasonable and effective training to improve the motor function of paralyzed extremity. In this paper, the developments of lower-limb rehabilitation robots in the past decades are reviewed. Specifically, we provide a classification, a comparison, and a design overview of the driving modes, training paradigm, and control strategy of the lower-limb rehabilitation robots in the reviewed literature. A brief review on the gait detection technology of lower-limb rehabilitation robots is also presented. Finally, we discuss the future directions of the lower-limb rehabilitation robots. PMID:28659660

Combined mirror visual and auditory feedback therapy for upper limb phantom pain: a case report

PubMed Central

2011-01-01

Introduction Phantom limb sensation and phantom limb pain is a very common issue after amputations. In recent years there has been accumulating data implicating 'mirror visual feedback' or 'mirror therapy' as helpful in the treatment of phantom limb sensation and phantom limb pain. Case presentation We present the case of a 24-year-old Caucasian man, a left upper limb amputee, treated with mirror visual feedback combined with auditory feedback with improved pain relief. Conclusion This case may suggest that auditory feedback might enhance the effectiveness of mirror visual feedback and serve as a valuable addition to the complex multi-sensory processing of body perception in patients who are amputees. PMID:21272334

Robotics in Lower-Limb Rehabilitation after Stroke.

PubMed

Zhang, Xue; Yue, Zan; Wang, Jing

2017-01-01

With the increase in the elderly, stroke has become a common disease, often leading to motor dysfunction and even permanent disability. Lower-limb rehabilitation robots can help patients to carry out reasonable and effective training to improve the motor function of paralyzed extremity. In this paper, the developments of lower-limb rehabilitation robots in the past decades are reviewed. Specifically, we provide a classification, a comparison, and a design overview of the driving modes, training paradigm, and control strategy of the lower-limb rehabilitation robots in the reviewed literature. A brief review on the gait detection technology of lower-limb rehabilitation robots is also presented. Finally, we discuss the future directions of the lower-limb rehabilitation robots.

Exploring the fine structure at the limb in coronal holes

NASA Technical Reports Server (NTRS)

Karovska, Magarita; Blundell, Solon F.; Habbal, Shadia Rifai

1994-01-01

The fine structure of the solar limb in coronal holes is explored at temperatures ranging from 10(exp 4) to 10(exp 6) K. An image enhancement algorithm orignally developed for solar eclipse observations is applied to a number of simultaneous multiwavelength observations made with the Harvard Extreme Ultraviolet Spectrometer experiment on Skylab. The enhanced images reveal the presence of filamentary structures above the limb with a characteristic separation of approximately 10 to 15 sec . Some of the structures extend from the solar limb into the corona to at least 4 min above the solar limb. The brightness of these structures changes as a function of height above the limb. The brightest emission is associated with spiculelike structures in the proximity of the limb. The emission characteristic of high-temperature plasma is not cospatial with the emission at lower temperatures, indicating the presence of different temperature plasmas in the field of view.

Limb immobilization and corticobasal syndrome.

PubMed

Graff-Radford, Jonathan; Boeve, Bradley F; Drubach, Daniel A; Knopman, David S; Ahlskog, J Eric; Golden, Erin C; Drubach, Dina I; Petersen, Ronald C; Josephs, Keith A

2012-12-01

Recently, we evaluated two patients with corticobasal syndrome (CBS) who reported symptom onset after limb immobilization. Our objective was to investigate the association between trauma, immobilization and CBS. The charts of forty-four consecutive CBS patients seen in the Mayo Clinic Alzheimer Disease Research Center were reviewed with attention to trauma and limb immobilization. 10 CBS patients (23%) had immobilization or trauma on the most affected limb preceding the onset or acceleration of symptoms. The median age at onset was 61. Six patients manifested their first symptoms after immobilization from surgery or fracture with one after leg trauma. Four patients had pre-existing symptoms of limb dysfunction but significantly worsened after immobilization or surgery. 23 percent of patients had immobilization or trauma of the affected limb. This might have implications for management of CBS, for avoiding injury, limiting immobilization and increasing movement in the affected limb. Copyright © 2012 Elsevier Ltd. All rights reserved.

Cross-education of wrist extensor strength is not influenced by non-dominant training in right-handers.

PubMed

Coombs, Timothy A; Frazer, Ashlyn K; Horvath, Deanna M; Pearce, Alan J; Howatson, Glyn; Kidgell, Dawson J

2016-09-01

Cross-education of strength has been proposed to be greater when completed by the dominant limb in right handed humans. We investigated whether the direction of cross-education of strength and corticospinal plasticity are different following right or left limb strength training in right-handed participants. Changes in strength, muscle thickness and indices of corticospinal plasticity were analyzed in 23 adults who were exposed to 3-weeks of either right-hand strength training (RHT) or left-hand strength training (LHT). Maximum voluntary wrist extensor strength in both the trained and untrained limb increased, irrespective of which limb was trained, with TMS revealing reduced corticospinal inhibition. Cross-education of strength was not limited by which limb was trained and reduced corticospinal inhibition was not just confined to the trained limb. Critically, from a behavioral perspective, the magnitude of cross-education was not limited by which limb was trained.

Surrogate: A Body-Dexterous Mobile Manipulation Robot with a Tracked Base

NASA Technical Reports Server (NTRS)

Hebert, Paul (Inventor); Borders, James W. (Inventor); Hudson, Nicolas H. (Inventor); Kennedy, Brett A. (Inventor); Ma, Jeremy C. (Inventor); Bergh, Charles F. (Inventor)

2018-01-01

Robotics platforms in accordance with various embodiments of the invention can be utilized to implement highly dexterous robots capable of whole body motion. Robotics platforms in accordance with one embodiment of the invention include: a memory containing a whole body motion application; a spine, where the spine has seven degrees of freedom and comprises a spine actuator and three spine elbow joints that each include two spine joint actuators; at least one limb, where the at least one limb comprises a limb actuator and three limb elbow joints that each include two limb joint actuators; a tracked base; a connecting structure that connects the at least one limb to the spine; a second connecting structure that connects the spine to the tracked base; wherein the processor is configured by the whole body motion application to move the at least one limb and the spine to perform whole body motion.

Pre- and Postoperative Evaluation by Photoplethysmography in Patients Receiving Surgery for Lower-Limb Varicose Veins

PubMed Central

Saliba Júnior, Orlando Adas; Giannini, Mariangela; Mórbio, Ana Paula; Saliba, Orlando; Rollo, Hamilton Almeida

2014-01-01

Objective. To evaluate the effectiveness of surgery in treating primary varicose veins in the lower limbs by photoplethysmography (PPG) and duplex mapping (DM). Method. Forty-eight lower limbs were clinically evaluated according to the CEAP classification system and subjected to PPG and DM exams. Each limb had a venous refill time (VRT) of <20 seconds and a normal deep vein system (DVS) by DM. Results. The mean pre- and postoperative VRTs were 13.79 and 26.43 seconds, respectively (P < 0.0001). After surgery, 42 limbs (87.50%) had normal results by PPG (VRT > 20 seconds). Four limbs (8.33%) showed improved VRTs, but the VRTs did not reach 20 seconds. In the 2 limbs (4.17%) that maintained their original VRTs, the DM exams showed the presence of insufficient perforating veins. Conclusion. In most cases, PPG allows for a satisfactory evaluation of the outcome of varicose vein surgery. PMID:24696783

Normal body scheme and absent phantom limb experience in amputees while dreaming.

PubMed

Alessandria, Maria; Vetrugno, Roberto; Cortelli, Pietro; Montagna, Pasquale

2011-12-01

While dreaming amputees often experience a normal body image and the phantom limb may not be present. However, dreaming experiences in amputees have mainly been collected by questionnaires. We analysed the dream reports of amputated patients with phantom limb collected after awakening from REM sleep during overnight videopolysomnography (VPSG). Six amputated patients underwent overnight VPSG study. Patients were awakened during REM sleep and asked to report their dreams. Three patients were able to deliver an account of a dream. In all dreaming recalls, patients reported that the amputated limbs were intact and completely functional and they no longer experienced phantom limb sensations. Phantom limb experiences, that during wake result from a conflict between a pre-existing body scheme and the sensory information on the missing limb, were suppressed during sleep in our patients in favour of the image of an intact body accessed during dream. Copyright © 2011 Elsevier Inc. All rights reserved.

Age-Related Differences in Bilateral Asymmetry in Cycling Performance

ERIC Educational Resources Information Center

Liu, Ting; Jensen, Jody L.

2012-01-01

Bilateral asymmetry, a form of limb laterality in the context of moving two limbs, emerges in childhood. Children and adults show lateral preference in tasks that involve the upper and lower limbs. The importance of research in limb laterality is the insight it could provide about lateralized functions of the cerebral hemispheres. Analyzing…

7 CFR 51.1220 - Leaf or limb rub injury.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 2 2014-01-01 2014-01-01 false Leaf or limb rub injury. 51.1220 Section 51.1220 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Leaf or limb rub injury. “Leaf or limb rub injury” means that the scarring is not smooth, not light...

7 CFR 51.1220 - Leaf or limb rub injury.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 2 2013-01-01 2013-01-01 false Leaf or limb rub injury. 51.1220 Section 51.1220 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Leaf or limb rub injury. “Leaf or limb rub injury” means that the scarring is not smooth, not light...

Limb observations of the 12.32 micron solar emission line during the 1991 July total eclipse

NASA Technical Reports Server (NTRS)

Deming, Drake; Jennings, Donald E.; Mccabe, George; Noyes, Robert; Wiedemann, Gunter; Espenak, Fred

1992-01-01

The limb profile of the Mg I 12.32-micron emission line is determined by occultation in the July 11, 1991 total solar eclipse over Mauna Kea. It is shown that the emission peaks are very close to the 12-micron continuum limb, as predicted by recent theory for this line as a non-LTE photospheric emission. The increase in optical depth for this extreme limb-viewing situation indicates that most of the observed emission arises from above the chromospheric temperature minimum, and it is found that this emission is extended to heights well in excess of the model predictions. The line emission can be observed as high as 2000 km above the 12-micron continuum limb, whereas theory predicts it to remain observable no higher than about 500 km above the continuum limb. The substantial limb extension observed in this line is quantitatively consistent with limb extensions seen in the far-IR continuum, and it is concluded that it is indicative of departures from gravitational hydrostatic equilibrium, or spatial inhomogeneities, in the upper solar atmosphere.

Multi-view light-sheet imaging and tracking with the MaMuT software reveals the cell lineage of a direct developing arthropod limb

PubMed Central

Stamataki, Evangelia; Harich, Benjamin; Guignard, Léo; Preibisch, Stephan; Shorte, Spencer; Keller, Philipp J

2018-01-01

During development, coordinated cell behaviors orchestrate tissue and organ morphogenesis. Detailed descriptions of cell lineages and behaviors provide a powerful framework to elucidate the mechanisms of morphogenesis. To study the cellular basis of limb development, we imaged transgenic fluorescently-labeled embryos from the crustacean Parhyale hawaiensis with multi-view light-sheet microscopy at high spatiotemporal resolution over several days of embryogenesis. The cell lineage of outgrowing thoracic limbs was reconstructed at single-cell resolution with new software called Massive Multi-view Tracker (MaMuT). In silico clonal analyses suggested that the early limb primordium becomes subdivided into anterior-posterior and dorsal-ventral compartments whose boundaries intersect at the distal tip of the growing limb. Limb-bud formation is associated with spatial modulation of cell proliferation, while limb elongation is also driven by preferential orientation of cell divisions along the proximal-distal growth axis. Cellular reconstructions were predictive of the expression patterns of limb development genes including the BMP morphogen Decapentaplegic. PMID:29595475

Roux limb volvulus in laparoscopic Roux-en-Y gastric bypass due to Roux limb stabilization suture: case series.

PubMed

Marr, Brendan; Yenumula, Panduranga

2012-01-01

Complications after laparoscopic Roux-en-Y gastric bypass surgery may be related to the type of surgical technique employed. One technique, the placement of a Roux limb stabilization suture, presumably prevents kink at the gastrojejunal anastomosis. However, it can have an adverse effect and we studied a series of cases presenting with intestinal obstruction secondary to this stitch. A retrospective review of a prospectively collected database of laparoscopic Roux-en-Y gastric bypass cases who had reoperations for Roux limb volvulus was performed at a single bariatric center by a single surgeon. Out of 199 patients who underwent laparoscopic Roux en Y gastric bypass with placement of Roux limb stabilization suture, 4 patients (2.01%) presented with Roux limb volvulus postoperatively. BMI was 45.35 ± 2.95. The postoperative time to presentation was 11 ± 10.6 months. All four patients required surgical exploration to reduce the volvulus. In all cases, the Roux limb volvulus was directly attributable to the presence of the stabilization suture. In subsequent 250 cases where this suture was eliminated, there was no volvulus of Roux limb seen. The use of a stabilization suture can result in volvulus of the Roux limb causing intestinal obstruction and this complication can be prevented by avoiding this suture.

The effects of prism glasses and intensive upper limb exercise on hemineglect, upper limb function, and activities of daily living in stroke patients: a case series.

PubMed

Oh, Se-Il; Kim, Jin-Kyung; Park, So-Yeon

2015-12-01

[Purpose] This study aimed to examine the effects of visual field with prism glasses, and intensive upper limb functional training on reduction of hemineglect and improvement in upper limb function and activities of daily living in three stroke patients with hemineglect. [Subjects] This study included three stroke patients hospitalized in a sanatorium. [Methods] Intervention treatment involving prism glass use for 12 hours and 30 minutes and paretic side upper limb training was conducted 5 days a week for 15 weeks. Three upper limb training tasks (hitting a balloon, passing through a ring, and reading a newspaper) were performed for 10 minutes each session, for a total of 30 minutes. Line by Section, Motor-Free Visual Perception Test-3 (MVPT-3), Manual Function Test (MFT), Box & Block Test (BBT), and Assessment of Motor and Process Skills (AMPS) were conducted before and after intervention. [Results] Subjects' hemineglect decreased and upper limb function on the paretic side improved after intervention, which enhanced activities of daily living. [Conclusion] Prism glass use and paretic upper limb functional training effectively ameliorated stroke patients' hemineglect and improved upper limb function. Future research should focus on prism glasses that provide a wide visual field for use in patients with different conditions.

Lower Limb Function in Elderly Korean Adults Is Related to Cognitive Function.

PubMed

Kim, A-Sol; Ko, Hae-Jin

2018-05-01

Patients with cognitive impairment have decreased lower limb function. Therefore, we aimed to investigate the relationship between lower limb function and cognitive disorders to determine whether lower limb function can be screened to identify cognitive decline. Using Korean National Health Insurance Service-National Sample Cohort database data, we assessed the cognitive and lower limb functioning of 66-year-olds who underwent national health screening between 2010 and 2014. Cognitive function was assessed via a questionnaire. Timed Up-and-Go (TUG) and one-leg-standing (OLS) tests were performed to evaluate lower limb function. Associations between cognitive and lower limb functions were analyzed, and optimal cut-off points for these tests to screen for cognitive decline, were determined. Cognitive function was significantly correlated with TUG interval ( r = 0.414, p < 0.001) and OLS duration ( r = −0.237, p < 0.001). Optimal cut-off points for screening cognitive disorders were >11 s and ≤12 s for TUG interval and OLS duration, respectively. Among 66-year-olds who underwent national health screening, a significant correlation between lower limb and cognitive function was demonstrated. The TUG and OLS tests are useful screening tools for cognitive disorders in elderly patients. A large-scale prospective cohort study should be conducted to investigate the causal relationship between cognitive and lower limb function.

Detection of genes regulated by Lmx1b during limb dorsalization.

PubMed

Feenstra, Jennifer M; Kanaya, Kohei; Pira, Charmaine U; Hoffman, Sarah E; Eppey, Richard J; Oberg, Kerby C

2012-05-01

Lmx1b is a homeodomain transcription factor that regulates dorsal identity during limb development. Lmx1b knockout (KO) mice develop distal ventral-ventral limbs. Although induction of Lmx1b is linked to Wnt7a expression in the dorsal limb ectoderm, the downstream targets of Lmx1b that accomplish limb dorsalization are unknown. To identify genes targeted by Lmx1b, we compared gene arrays from Lmx1b KO and wild type mouse limbs during limb dorsalization, i.e., 11.5, 12.5, and 13.5 days post coitum. We identified 54 target genes that were differentially expressed in all three stages. Several skeletal targets, including Emx2, Matrilin1 and Matrilin4, demonstrated a loss of scapular expression in the Lmx1b KO mice, supporting a role for Lmx1b in scapula development. Furthermore, the relative abundance of extracellular matrix-related soft tissue targets regulated by Lmx1b, such as collagens and proteoglycans, suggests a mechanism that includes changes in the extracellular matrix composition to accomplish limb dorsalization. Our study provides the most comprehensive characterization of genes regulated by Lmx1b during limb development to-date and provides targets for further investigation. © 2012 The Authors. Development, Growth & Differentiation © 2012 Japanese Society of Developmental Biologists.

Expression of Msx genes in regenerating and developing limbs of axolotl.

PubMed

Koshiba, K; Kuroiwa, A; Yamamoto, H; Tamura, K; Ide, H

1998-12-15

Msx genes, homeobox-containing genes, have been isolated as homologues of the Drosophila msh gene and are thought to play important roles in the development of chick or mouse limb buds. We isolated two Msx genes, Msx1 and Msx2, from regenerating blastemas of axolotl limbs and examined their expression patterns using Northern blot and whole mount in situ hybridization during regeneration and development. Northern blot analysis revealed that the expression level of both Msx genes increased during limb regeneration. The Msx2 expression level increased in the blastema at the early bud stage, and Msx1 expression level increased at the late bud stage. Whole mount in situ hybridization revealed that Msx2 was expressed in the distal mesenchyme and Msx1 in the entire mesenchyme of the blastema at the late bud stage. In the developing limb bud, Msx1 was expressed in the entire mesenchyme, while Msx2 was expressed in the distal and peripheral mesenchyme. The expression patterns of Msx genes in the blastemas and limb buds of the axolotl were different from those reported for chick or mouse limb buds. These expression patterns of axolotl Msx genes are discussed in relation to the blastema or limb bud morphology and their possible roles in limb patterning.

Bilateral electromyogram response latency following platform perturbation in unilateral transtibial prosthesis users: influence of weight distribution and limb position.

PubMed

Rusaw, David; Hagberg, Kerstin; Nolan, Lee; Ramstrand, Nerrolyn

2013-01-01

Appropriate muscular response following an external perturbation is essential in preventing falls. Transtibial prosthesis users lack a foot-ankle complex and associated sensorimotor structures on the side with the prosthesis. The effect of this lack on rapid responses of the lower limb to external surface perturbations is unknown. The aim of the present study was to compare electromyogram (EMG) response latencies of otherwise healthy, unilateral, transtibial prosthesis users (n = 23, mean +/- standard deviation [SD] age = 48 +/- 14 yr) and a matched control group (n = 23, mean +/- SD age = 48 +/- 13 yr) following sudden support-surface rotations in the pitch plane (toes-up and toes-down). Perturbations were elicited in various weight-bearing and limb-perturbed conditions. The results indicated that transtibial prosthesis users have delayed responses of multiple muscles of the lower limb following perturbation, both in the intact and residual limbs. Weight-bearing had no influence on the response latency in the residual limb, but did on the intact limb. Which limb received the perturbation was found to influence the muscular response, with the intact limb showing a significantly delayed response when the perturbation was received only on the side with a prosthesis. These delayed responses may represent an increased risk of falling for individuals who use transtibial prostheses.

Motor exam of patients with spinal cord injury: a terminological imbroglio.

PubMed

Figueiredo, Nicandro

2017-07-01

The description of the motor deficit of patients with spinal cord injury (SCI) varies significantly, leading to confusion within the neurological terminology. This paper proposes a concise and easy to use terminology to describe the motor deficit of patients with SCI. A broad review of the origin of the nomenclature used to describe the motor deficit of patients with SCI was performed and discussed. The prefix: "hemi" should be used to describe paralysis of one half of the body; "mono" for one limb; "para" for lower limbs, di" for two symmetrical segments and/or parts in both sides of the body; "tri" for three limbs, or two limbs and one side of the face; and "tetra" for four limbs. The suffix: "plegia" should be used for total paralysis of a limb or part of the body, and "paresis" for partial paralysis. The term "brachial" refers to the upper limbs; and "podal" to the lower limbs. According to the spinal cord origin of the main key muscles for the limbs, patients with complete injury affecting spinal cord segments C1-5 usually presents with "tetraplegia"; C6-T1 presents with "paraplegia and brachial diparesis"; T2-L2 with "paraplegia"; and L3-S1 with "paraparesis".

Delayed amputation following trauma increases residual lower limb infection.

PubMed

Jain, Abhilash; Glass, Graeme E; Ahmadi, Hootan; Mackey, Simon; Simmons, Jon; Hettiaratchy, Shehan; Pearse, Michael; Nanchahal, Jagdeep

2013-04-01

Residual limb infection following amputation is a devastating complication, resulting in delayed rehabilitation, repeat surgery, prolonged hospitalisation and poor functional outcome. The aim of this study was to identify variables predicting residual limb infection following non-salvageable lower limb trauma. All cases of non-salvageable lower limb trauma presenting to a specialist centre over 5 years were evaluated from a prospective database and clinical and management variables correlated with the development of deep infection. Forty patients requiring 42 amputations were identified with a mean age of 49 years (±19.9, 1SD). Amputations were performed for 21 Gustilo IIIB injuries, 12 multi-planar degloving injuries, seven IIIC injuries and one open Schatzker 6 fracture. One limb was traumatically amputated at the scene and surgically revised. Amputation level was transtibial in 32, through-knee in one and transfemoral in nine. Median time from injury to amputation was 4 days (range 0-30 days). Amputation following only one debridement and within 5 days resulted in significantly fewer stump infections (p = 0.026 and p = 0.03, respectively, Fisher's exact test). The cumulative probability of infection-free residual limb closure declined steadily from day 5. Multivariate analyses revealed that neither the nature of the injury nor pre-injury patient morbidity independently influenced residual limb infection. Avoiding residual limb infection is critically dependent on prompt amputation of non-salvageable limbs. Copyright © 2012 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Assessment of radial torsion using computed tomography in dogs with and without antebrachial limb deformity.

PubMed

Kroner, Kevin; Cooley, Katie; Hoey, Seamus; Hetzel, Scott J; Bleedorn, Jason A

2017-01-01

To evaluate the reliability of radial torsion assessment in dogs using computed tomography (CT). Cadaveric and retrospective observational clinical study. Thoracic limbs (n = 40) from bilateral normal cadaveric canine specimens (10 pairs) and unilateral antebrachial angular limb deformity (ALD) dogs (10 uniapical and 10 biapical deformities). Limbs were evaluated using CT. Frontal, sagittal, and axial plane (torsion) values were obtained using published guidelines and compared between groups and limbs. Radial torsion reliability was assessed among 3 observers using intraclass correlation coefficients (ICC). The mean (±SD) radial torsion of normal dogs was 3.6° ± 6.4° and contained a significant right to left limb variation of 2.6°. Mean radial torsion in uniapical ALD limbs (3.6° ± 18.7°) was not significantly different from biapical ALD limbs (8.9° ± 17.9°). There was a wide range of torsion values in normal and ALD limbs. The interobserver reliability was excellent (ICC > 0.8) for normal dogs, good (0.73) for uniapical, and excellent (0.89) for biapical ALD limbs. The intraobserver reliability was excellent (>0.8) for all groups. There was a small side-to-side variation of radial torsion in normal dogs. With directed training, torsion assessment using CT is reliable in dogs with and without antebrachial bone deformity. © 2016 The American College of Veterinary Surgeons.

Manipulated Changes in Limb Mass and Rotational Inertia in Trotting Dogs (Canis lupus familiaris) and Their Effect on Limb Kinematics.

PubMed

Kilbourne, Brandon M; Carrier, David R

2016-12-01

While the mass distribution of limbs is known to influence the metabolic energy consumed during locomotion, it remains unknown how the mass distribution of limbs may influence overall limb kinematics and whether the influence of limb mass distribution on limb kinematics differs between fore- and hindlimbs. To examine limb mass distribution's influence upon fore- and hindlimb kinematics, temporal stride parameters and swing phase joint kinematics were recorded from four dogs trotting on a treadmill with 0.5% and 1.0% body mass added to each limb, forelimbs alone, and hindlimbs alone, as well as with no added mass. Under all loading conditions, stride period did not differ between fore- and hindlimbs; however, forelimbs exhibited greater duty factors and stance durations, whereas hindlimbs exhibited greater swing durations, which may be related to the hindlimb's greater mass. Changes in forelimb joint and hip range of motion (RoM), flexion, and extension were subject to a high amount of kinematic plasticity among dogs. In contrast, for the knee and ankle, distally loading all four limbs or hindlimbs alone substantially increased joint RoM and flexion. Increased flexion of the knee and ankle has the potential to reduce the hindlimb's rotational inertia during swing phase. The differing response of fore- and hindlimbs with regard to joint kinematics is likely due to differences in their mass and mass distribution and differences in the physiological traits of fore- and hindlimb protractors and joint flexors. © 2017 Wiley Periodicals, Inc.

Acute limb heating improves macro- and microvascular dilator function in the leg of aged humans.

PubMed

Romero, Steven A; Gagnon, Daniel; Adams, Amy N; Cramer, Matthew N; Kouda, Ken; Crandall, Craig G

2017-01-01

Local heating of an extremity increases blood flow and vascular shear stress throughout the arterial tree. Local heating acutely improves macrovascular dilator function in the upper limbs of young healthy adults through a shear stress-dependent mechanism but has no such effect in the lower limbs of this age group. The effect of acute limb heating on dilator function within the atherosclerotic prone vasculature of the lower limbs of aged adults is unknown. Therefore, the purpose of this study was to test the hypothesis that acute lower limb heating improves macro- and microvascular dilator function within the leg vasculature of aged adults. Nine young and nine aged adults immersed their lower limbs at a depth of ~33 cm into a heated (~42°C) circulated water bath for 45 min. Before and 30 min after heating, macro (flow-mediated dilation)- and microvascular (reactive hyperemia) dilator functions were assessed in the lower limb, following 5 min of arterial occlusion, via Doppler ultrasound. Compared with preheat, macrovascular dilator function was unchanged following heating in young adults (P = 0.6) but was improved in aged adults (P = 0.04). Similarly, microvascular dilator function, as assessed by peak reactive hyperemia, was unchanged following heating in young adults (P = 0.1) but was improved in aged adults (P < 0.01). Taken together, these data suggest that acute lower limb heating improves both macro- and microvascular dilator function in an age dependent manner. We demonstrate that lower limb heating acutely improves macro- and microvascular dilator function within the atherosclerotic prone vasculature of the leg in aged adults. These findings provide evidence for a potential therapeutic use of chronic lower limb heating to improve vascular health in primary aging and various disease conditions. Copyright © 2017 the American Physiological Society.

Influence of maturation on instep kick biomechanics in female soccer athletes.

PubMed

Lyle, Mark A; Sigward, Susan M; Tsai, Liang-Ching; Pollard, Christine D; Powers, Christopher M

2011-10-01

The purpose of this study was to compare kicking biomechanics between young female soccer players at two different stages of physical maturation and to identify biomechanical predictors of peak foot velocity. Swing and stance limb kinematics and kinetics were recorded from 20 female soccer players (10 prepubertal, 10 postpubertal) while kicking a soccer ball using an angled two-step approach. Peak foot velocity as well as hip and knee kinematics and kinetics were compared between groups using independent-samples t-tests. Pearson correlation coefficients and stepwise multiple regression were used to identify predictors of peak foot velocity. Peak foot velocity and the peak swing limb net hip flexor moment was significantly greater in the postpubertal group when compared with the prepubertal group (13.4 vs 11.6 m·s(-1), P = 0.003; 1.22 vs 1.07 N·m·kg(-1)·m(-1), P = 0.03). Peak stance limb hip and knee extensor moments were not different between groups. Although the peak swing limb hip and knee flexion angles were similar between groups, the postpubertal group demonstrated significantly less peak stance limb hip and knee flexion angles when compared with the prepubertal group (P < 0.001 and P = 0.045). Using a linear regression model, swing limb peak hip flexor moment and peak swing limb hip extension range of motion combined to explain 65% of the variance in peak foot velocity. Despite a difference in stance limb kinematics, similar swing limb kinematics between groups indicates that the prepubertal female athletes kicked with a mature swing limb kick pattern. The ability to generate a large hip flexor moment of the swing limb seems to be an important factor for improving kicking performance in young female soccer players.

Reactivation of larval keratin gene (krt62.L) in blastema epithelium during Xenopus froglet limb regeneration.

PubMed

Satoh, Akira; Mitogawa, Kazumasa; Saito, Nanami; Suzuki, Miyuki; Suzuki, Ken-Ichi T; Ochi, Haruki; Makanae, Aki

2017-12-15

Limb regeneration is considered a form of limb redevelopment because of the molecular and morphological similarities. Forming a regeneration blastema is, in essence, creating a developing limb bud in an adult body. This reactivation of a developmental process in a mature body is worth studying. Xenopus laevis has a biphasic life cycle that involves distinct larval and adult stages. These distinct developmental stages are useful for investigating the reactivation of developmental processes in post-metamorphic frogs (froglets). In this study, we focused on the re-expression of a larval gene (krt62.L) during Xenopus froglet limb regeneration. Recently renamed krt62.L, this gene was known as the larval keratin (xlk) gene, which is specific to larval-tadpole stages. During limb regeneration in a froglet, krt62.L was re-expressed in a basal layer of blastema epithelium, where adult-specific keratin (Krt12.6.S) expression was also observable. Nerves produce important regulatory factors for amphibian limb regeneration, and also play a role in blastema formation and maintenance. The effect of nerve function on krt62.L expression could be seen in the maintenance of krt62.L expression, but not in its induction. When an epidermis-stripped limb bud was grafted in a froglet blastema, the grafted limb bud could reach the digit-forming stage. This suggests that krt62.L-positive froglet blastema epithelium is able to support the limb development process. These findings imply that the developmental process is locally reactivated in an postmetamorphic body during limb regeneration. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Structure design of lower limb exoskeletons for gait training

NASA Astrophysics Data System (ADS)

Li, Jianfeng; Zhang, Ziqiang; Tao, Chunjing; Ji, Run

2015-09-01

Due to the close physical interaction between human and machine in process of gait training, lower limb exoskeletons should be safe, comfortable and able to smoothly transfer desired driving force/moments to the patients. Correlatively, in kinematics the exoskeletons are required to be compatible with human lower limbs and thereby to avoid the uncontrollable interactional loads at the human-machine interfaces. Such requirement makes the structure design of exoskeletons very difficult because the human-machine closed chains are complicated. In addition, both the axis misalignments and the kinematic character difference between the exoskeleton and human joints should be taken into account. By analyzing the DOF(degree of freedom) of the whole human-machine closed chain, the human-machine kinematic incompatibility of lower limb exoskeletons is studied. An effective method for the structure design of lower limb exoskeletons, which are kinematically compatible with human lower limb, is proposed. Applying this method, the structure synthesis of the lower limb exoskeletons containing only one-DOF revolute and prismatic joints is investigated; the feasible basic structures of exoskeletons are developed and classified into three different categories. With the consideration of quasi-anthropopathic feature, structural simplicity and wearable comfort of lower limb exoskeletons, a joint replacement and structure comparison based approach to select the ideal structures of lower limb exoskeletons is proposed, by which three optimal exoskeleton structures are obtained. This paper indicates that the human-machine closed chain formed by the exoskeleton and human lower limb should be an even-constrained kinematic system in order to avoid the uncontrollable human-machine interactional loads. The presented method for the structure design of lower limb exoskeletons is universal and simple, and hence can be applied to other kinds of wearable exoskeletons.

Attenuation of bone morphogenetic protein signaling during amphibian limb development results in the generation of stage-specific defects.

PubMed

Jones, Tamsin E M; Day, Robert C; Beck, Caroline W

2013-11-01

The vertebrate limb is one of the most intensively studied organs in the field of developmental biology. Limb development in tetrapod vertebrates is highly conserved and dependent on the interaction of several important molecular pathways. The bone morphogenetic protein (BMP) signaling cascade is one of these pathways and has been shown to be crucial for several aspects of limb development. Here, we have used a Xenopus laevis transgenic line, in which expression of the inhibitor Noggin is under the control of the heat-shock promoter hsp70 to examine the effects of attenuation of BMP signaling at different stages of limb development. Remarkably different phenotypes were produced at different stages, illustrating the varied roles of BMP in development of the limb. Very early limb buds appeared to be refractory to the effects of BMP attenuation, developing normally in most cases. Ectopic limbs were produced by overexpression of Noggin corresponding to a brief window of limb development at about stage 49/50, as recently described by Christen et al. (2012). Attenuation of BMP signaling in stage 51 or 52 tadpoles lead to a reduction in the number of digits formed, resulting in hypodactyly or ectrodactyly, as well as occasional defects in the more proximal tibia-fibula. Finally, inhibition at stage 54 (paddle stage) led to the formation of dramatically shortened digits resulting from loss of distal phalanges. Transcriptome analysis has revealed the possibility that more Noggin-sensitive members of the BMP family could be involved in limb development than previously suspected. Our analysis demonstrates the usefulness of heat-shock-driven gene expression as an effective method for inhibiting a developmental pathway at different times during limb development. © 2013 Anatomical Society.

Sonic Hedgehog Signaling in Limb Development

PubMed Central

Tickle, Cheryll; Towers, Matthew

2017-01-01

The gene encoding the secreted protein Sonic hedgehog (Shh) is expressed in the polarizing region (or zone of polarizing activity), a small group of mesenchyme cells at the posterior margin of the vertebrate limb bud. Detailed analyses have revealed that Shh has the properties of the long sought after polarizing region morphogen that specifies positional values across the antero-posterior axis (e.g., thumb to little finger axis) of the limb. Shh has also been shown to control the width of the limb bud by stimulating mesenchyme cell proliferation and by regulating the antero-posterior length of the apical ectodermal ridge, the signaling region required for limb bud outgrowth and the laying down of structures along the proximo-distal axis (e.g., shoulder to digits axis) of the limb. It has been shown that Shh signaling can specify antero-posterior positional values in limb buds in both a concentration- (paracrine) and time-dependent (autocrine) fashion. Currently there are several models for how Shh specifies positional values over time in the limb buds of chick and mouse embryos and how this is integrated with growth. Extensive work has elucidated downstream transcriptional targets of Shh signaling. Nevertheless, it remains unclear how antero-posterior positional values are encoded and then interpreted to give the particular structure appropriate to that position, for example, the type of digit. A distant cis-regulatory enhancer controls limb-bud-specific expression of Shh and the discovery of increasing numbers of interacting transcription factors indicate complex spatiotemporal regulation. Altered Shh signaling is implicated in clinical conditions with congenital limb defects and in the evolution of the morphological diversity of vertebrate limbs. PMID:28293554

How do somatosensory deficits in the arm and hand relate to upper limb impairment, activity, and participation problems after stroke? A systematic review.

PubMed

Meyer, Sarah; Karttunen, Auli H; Thijs, Vincent; Feys, Hilde; Verheyden, Geert

2014-09-01

The association between somatosensory impairments and outcome after stroke remains unclear. The aim of this study was to systematically review the available literature on the relationship between somatosensory impairments in the upper limb and outcome after stroke. The electronic databases PubMed, CINAHL, EMBASE, Cochrane Library, PsycINFO, and Web of Science were systematically searched from inception until July 2013. Studies were included if adult patients with stroke (minimum n=10) were examined with reliable and valid measures of somatosensation in the upper limb to investigate the relationship with upper limb impairment, activity, and participation measures. Exclusion criteria included measures of somatosensation involving an overall score for upper and lower limb outcome and articles including only lower limb outcomes. Eligibility assessment, data extraction, and quality evaluation were completed by 2 independent reviewers. A cutoff score of ≥65% of the maximal quality score was used for further inclusion in this review. Six articles met all inclusion criteria. Two-point discrimination was shown to be predictive for upper limb dexterity, and somatosensory evoked potentials were shown to have predictive value in upper limb motor recovery. Proprioception was significantly correlated with perceived level of physical activity and social isolation and had some predictive value in functional movements of the upper limb. Finally, the combination of light touch and proprioception impairment was shown to be significantly related to upper limb motor recovery as well as handicap situations during activities of daily living. Heterogeneity of the included studies warrants caution when interpreting results. Large variation in results was found due to heterogeneity of the studies. However, somatosensory deficits were shown to have an important role in upper limb motor and functional performance after stroke. © 2014 American Physical Therapy Association.

[Psychotherapies for the Treatment of Phantom Limb Pain].

PubMed

Cárdenas, Katherine; Aranda, Mariana

The phantom limb pain has been described as a condition in which patients experience a feeling of itching, spasm or pain in a limb or body part that has been previously amputated. Such pain can be induced by a conflict between the representation of the visual and proprioceptive feedback of the previously healthy limb. The phantom limb pain occurs in at least 42 to 90% of amputees. Regular drug treatment of phantom limb pain is almost never effective. A systematic review of the literature was conducted in Medline and Cochrane using the MESH terms "phantom limb pain" and "psychotherapy", published in the last 10 years, in English and Spanish, finding 49 items. After reviewing the abstracts, 25 articles were excluded for not being related to the objective of the research. Additionally cross references of included articles and literature were reviewed. To describe the psychotherapies used in the management of phantom limb pain, their effectiveness and clinical application reported in the literature. The mechanisms underlying phantom limb pain were initially explained, as were the published studies on the usefulness of some psychotherapies such as mirror visual feedback and immersive virtual reality, visual imagery, desensitization and reprocessing eye movements and hypnosis. The phantom limb pain is a complex syndrome that requires pharmacological and psychotherapeutic intervention. The psychotherapies that have been used the most as adjuvants in the treatment of phantom limb pain are mirror visual feedback, desensitization and reprocessing eye movements, imagery and hypnosis. Studies with more representative samples, specifically randomized trials are required. Copyright © 2016 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

Periodic Limb Movements during Sleep and Cardiac Arrhythmia in Older Men (MrOS Sleep)

PubMed Central

Koo, Brian B.; Mehra, Reena; Blackwell, Terri; Ancoli-Israel, Sonia; Stone, Katie L.; Redline, Susan

2014-01-01

Study Objectives: To determine if periodic limb movements during sleep (PLMS) are associated with nocturnal cardiac arrhythmia. Methods: 2,793 community-dwelling older men underwent polysomnography with measurement of limb movements and EKG. Logistic regression assessed association of periodic limb movement index and periodic limb movement arousal index with arrhythmia including atrial fibrillation and non-sustained ventricular tachycardia detected by polysomnography. Models were adjusted for age, race, cardiovascular risk factors, and clinic site. Secondary analyses were subset to men without calcium channel/β-adrenergic medication usage, and stratified by congestive heart failure or myocardial infarction history. Results: In the overall cohort, periodic limb movement index, and periodic limb movement arousal index were not associated with ventricular or atrial arrhythmia after considering potential confounders. In men not taking calcium channel/β-blocking medication, increased adjusted odds of non-sustained ventricular tachycardia were observed for periodic limb movement index (OR = 1.30 per SD increase; 95% CI 1.00, 1.68) and periodic limb movement arousal index (OR = 1.29 per SD increase; 95% CI 1.03, 1.62). In men with CHF or MI, there was a suggested association of atrial fibrillation with periodic limb movement index (OR = 1.29, 95% CI 0.96, 1.73 per SD increase; p = 0.09) or periodic limb movement arousal index (OR = 1.21, 95% CI 0.94, 1.57 per SD increase; p = 0.14), although results were not statistically significant. Conclusions: There is not an association between PLMS and cardiac arrhythmia in all older men but in subsets of men, particularly those with structural heart disease and not on calcium channel or β-adrenergic medication, cardiac arrhythmia does associate with PLMS. Citation: Koo BB; Mehra R; Blackwell T; Ancoli-Israel S; Stone KL; Redline S; for the Osteoporotic Fractures in Men (MrOS) Study Group. Periodic limb movements during sleep and cardiac arrhythmia in older men (MrOS sleep). J Clin Sleep Med 2014;10(1):7-11. PMID:24426814

Limb Correction of Infrared Imagery in Cloudy Regions for the Improved Interpretation of RGB Composites

NASA Technical Reports Server (NTRS)

Elmer, Nicholas J.; Berndt, Emily; Jedlovec, Gary J.

2016-01-01

Red-Green-Blue (RGB) composites (EUMETSAT User Services 2009) combine information from several channels into a single composite image. RGB composites contain the same information as the original channels, but presents the information in a more efficient manner. However, RGB composites derived from infrared imagery of both polar-orbiting and geostationary sensors are adversely affected by the limb effect, which interferes with the qualitative interpretation of RGB composites at large viewing zenith angles. The limb effect, or limb-cooling, is a result of an increase in optical path length of the absorbing atmosphere as viewing zenith angle increases (Goldberg et al. 2001; Joyce et al. 2001; Liu and Weng 2007). As a result, greater atmospheric absorption occurs at the limb, causing the sensor to observe anomalously cooler brightness temperatures. Figure 1 illustrates this effect. In general, limb-cooling results in a 4-11 K decrease in measured brightness temperature (Liu and Weng 2007) depending on the infrared band. For example, water vapor and ozone absorption channels display much larger limb-cooling than infrared window channels. Consequently, RGB composites created from infrared imagery not corrected for limb effects can only be reliably interpreted close to nadir, which reduces the spatial coverage of the available imagery. Elmer (2015) developed a reliable, operational limb correction technique for clear regions. However, many RGB composites are intended to be used and interpreted in cloudy regions, so a limb correction methodology valid for both clear and cloudy regions is needed. This paper presents a limb correction technique valid for both clear and cloudy regions, which is described in Section 2. Section 3 presents several RGB case studies demonstrating the improved functionality of limb-corrected RGBs in both clear and cloudy regions, and Section 4 summarizes and presents the key conclusions of this work.

A nationwide analysis of 30-day readmissions related to critical limb ischemia.

PubMed

Masoomi, Reza; Shah, Zubair; Quint, Clay; Hance, Kirk; Vamanan, Karthik; Prasad, Anand; Hoel, Andrew; Dawn, Buddhadeb; Gupta, Kamal

2018-06-01

Objectives There is paucity of information regarding critical limb ischemia-related readmission rates in patients admitted with critical limb ischemia. We studied 30-day critical limb ischemia-related readmission rate, its predictors, and clinical outcomes using a nationwide real-world dataset. Methods We did a secondary analysis of the 2013 Nationwide Readmissions Database. We included all patients with a primary diagnosis of extremity rest pain, ulceration, and gangrene secondary to peripheral arterial disease. From this group, all patients readmitted with similar diagnosis within 30 days were recorded. Results Of the total 25,111 index hospitalization for critical limb ischemia, 1270 (5%) were readmitted with a primary diagnosis of critical limb ischemia within 30 days. The readmission rate was highest (9.5%) for the group that did not have any intervention (revascularization or major amputation) and was lowest for surgical revascularization and major amputation groups (2.6% and 1.3%, P value <0.001 for all groups). Severity of critical limb ischemia at index admission was associated with a significantly higher rate of 30-day readmission. Critical limb ischemia-related readmission was associated with a higher rate of major amputation (29.6% vs. 16.2%, P<0.001), a lower rate of any revascularization procedure (46% vs. 62.6%, P<0.001), and a higher likelihood of discharge to a skilled nursing facility (43.2% vs. 32.2%, P<0.001) compared to index hospitalization. Conclusions In patients with primary diagnosis of critical limb ischemia, 30-day critical limb ischemia-related readmission rate was affected by initial management strategy and the severity of critical limb ischemia. Readmission was associated with a significantly higher rate of amputation, increased length of stay, and a more frequent discharge to an alternate care facility than index admission and thus may serve as a useful quality of care metric in critical limb ischemia patients.

Running stability is enhanced by a proximo-distal gradient in joint neuromechanical control.

PubMed

Daley, M A; Felix, G; Biewener, A A

2007-02-01

We currently know little about how animals achieve dynamic stability when running over uneven and unpredictable terrain, often characteristic of their natural environment. Here we investigate how limb and joint mechanics of an avian biped, the helmeted guinea fowl Numida meleagris, respond to an unexpected drop in terrain during running. In particular, we address how joint mechanics are coordinated to achieve whole limb dynamics. Based on muscle-tendon architecture and previous studies of steady and incline locomotion, we hypothesize a proximo-distal gradient in joint neuromechanical control. In this motor control strategy, (1) proximal muscles at the hip and knee joints are controlled primarily in a feedforward manner and exhibit load-insensitive mechanical performance, and (2) distal muscles at the ankle and tarsometatarso-phalangeal (TMP) joints are highly load-sensitive, due to intrinsic mechanical effects and rapid, higher gain proprioceptive feedback. Limb kinematics and kinetics during the unexpected perturbation reveal that limb retraction, controlled largely by the hip, remains similar to level running throughout the perturbed step, despite altered limb loading. Individual joints produce or absorb energy during both level and perturbed running steps, such that the net limb work depends on the balance of energy among the joints. The hip maintains the same mechanical role regardless of limb loading, whereas the ankle and TMP switch between spring-like or damping function depending on limb posture at ground contact. Initial knee angle sets limb posture and alters the balance of work among the joints, although the knee contributes little work itself. This distribution of joint function results in posture-dependent changes in work performance of the limb, which allow guinea fowl to rapidly produce or absorb energy in response to the perturbation. The results support the hypothesis that a proximo-distal gradient exists in limb neuromuscular performance and motor control. This control strategy allows limb cycling to remain constant, whereas limb posture, loading and energy performance are interdependent. We propose that this control strategy provides simple, rapid mechanisms for managing energy and controlling velocity when running over rough terrain.

Running stability is enhanced by a proximo-distal gradient in joint neuromechanical control

PubMed Central

Daley, M. A.; Felix, G.; Biewener, A. A.

2008-01-01

Summary We currently know little about how animals achieve dynamic stability when running over uneven and unpredictable terrain, often characteristic of their natural environment. Here we investigate how limb and joint mechanics of an avian biped, the helmeted guinea fowl Numida meleagris, respond to an unexpected drop in terrain during running. In particular, we address how joint mechanics are coordinated to achieve whole limb dynamics. Based on muscle–tendon architecture and previous studies of steady and incline locomotion, we hypothesize a proximo-distal gradient in joint neuromechanical control. In this motor control strategy, (1) proximal muscles at the hip and knee joints are controlled primarily in a feedforward manner and exhibit load-insensitive mechanical performance, and (2) distal muscles at the ankle and tarsometatarso-phalangeal (TMP) joints are highly load-sensitive, due to intrinsic mechanical effects and rapid, higher gain proprioceptive feedback. Limb kinematics and kinetics during the unexpected perturbation reveal that limb retraction, controlled largely by the hip, remains similar to level running throughout the perturbed step, despite altered limb loading. Individual joints produce or absorb energy during both level and perturbed running steps, such that the net limb work depends on the balance of energy among the joints. The hip maintains the same mechanical role regardless of limb loading, whereas the ankle and TMP switch between spring-like or damping function depending on limb posture at ground contact. Initial knee angle sets limb posture and alters the balance of work among the joints, although the knee contributes little work itself. This distribution of joint function results in posture-dependent changes in work performance of the limb, which allow guinea fowl to rapidly produce or absorb energy in response to the perturbation. The results support the hypothesis that a proximo-distal gradient exists in limb neuromuscular performance and motor control. This control strategy allows limb cycling to remain constant, whereas limb posture, loading and energy performance are interdependent. We propose that this control strategy provides simple, rapid mechanisms for managing energy and controlling velocity when running over rough terrain. PMID:17234607

Changes in expression of the lysosomal membrane glycoprotein, LAMP-1 in interdigital regions during embryonic mouse limb development, in vivo and in vitro.

PubMed

Stewart, S; Yi, S; Kassabian, G; Mayo, M; Sank, A; Shuler, C

2000-06-01

Syndactyly, a failure of the digits to separate into individual units, affects about 8 to 9 per 1000 newborns and results from an aberration of the normal development of the interdigital tissues. Limb digit separation is the result of programmed cell death (apoptosis). Lysosomes play a role in the process of cell self-destruction. Our experiment was designed to test the hypothesis that the intensity of interdigital lysosomes increases during the separation of digits in vivo and in vitro. The primary mouse monoclonal antibody, 1D4B, detects the presence of lysosomes by identifying the LAMP-1 glycoprotein on the lysosome cell membrane. In our experiment this antibody immunodetected interdigital lysosome proteins in serial sections of limbs from Swiss-Webster mouse embryos, gestational ages E12.5 through E15, key developmental stages for digit separation. Digit separation was associated with an increase in intensity of lysosomal protein staining. In E12.5 limbs, the presence of lysosomes was enriched in the distal aspect of the interdigital tissue. However, the number of lysosomes markedly increased in the E13 and E14 limbs, including the entire length and width of the interdigital tissue in the E14 limbs. This lysosomal protein presence in E14 limbs was significant compared to E12.5, E13, and E15 limbs. By day 12.5, the mouse embryo limb is committed to digit separation. Addition of retinoic acid to the culture medium of limbs earlier in development, such as E12, results in induction of the process of digit separation. Cultured E12 limbs that did not receive an addition of retinoic acid, did not show digit separation. We conclude that in the limb development process, the enrichment in interdigit LAMP-1 proteins, may indicate a relationship between lysosomes, apoptosis, and digit separation. We also conclude that retinoic acid has an important role in digit separation in vivo, as shown in limb development, and demonstrated through the addition of retinoic acid to media of cultured tissues.

Grading sugar pine saw logs in trees.

Treesearch

John W. Henley

1972-01-01

Small limbs and small overgrown limbs cause problems when grading saw logs in sugar pine trees. Surface characteristics and lumber recovery information for 426 logs from 64 sugar pine trees were examined. Resulting modifications in the grading specification that allow a grader to ignore small limbs and small limb indicators do not appear to decrease the performance of...

LIMB DEFECTS INDUCED BY RETINOIC ACID SIGNALING ANTAGONISM AND SYNTHESIS INHIBITION ARE CONSISTENT WITH ETHANOL-INDUCED LIMB DEFECTS

EPA Science Inventory

Limb defects induced by retinoic acid signaling antagonism and synthesis inhibition are consistent with ethanol-induced limb defects

Johnson CS1, Sulik KK1,2, Hunter, ES III3
1Department of Cell and Developmental Biology, University of North Carolina at Chapel Hill, NC....

Motor Impairment Evaluation for Upper Limb in Stroke Patients on the Basis of a Microsensor

ERIC Educational Resources Information Center

Huang, Shuai; Luo, Chun; Ye, Shiwei; Liu, Fei; Xie, Bin; Wang, Caifeng; Yang, Li; Huang, Zhen; Wu, Jiankang

2012-01-01

There has been an urgent need for an effective and efficient upper limb rehabilitation method for poststroke patients. We present a Micro-Sensor-based Upper Limb rehabilitation System for poststroke patients. The wearable motion capture units are attached to upper limb segments embedded in the fabric of garments. The body segment orientation…

7 CFR 51.1220 - Leaf or limb rub injury.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf or limb rub injury. 51.1220 Section 51.1220... STANDARDS) United States Standards for Grades of Peaches Definitions § 51.1220 Leaf or limb rub injury. “Leaf or limb rub injury” means that the scarring is not smooth, not light colored, or aggregates more...

7 CFR 51.1220 - Leaf or limb rub injury.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 2 2011-01-01 2011-01-01 false Leaf or limb rub injury. 51.1220 Section 51.1220... STANDARDS) United States Standards for Grades of Peaches Definitions § 51.1220 Leaf or limb rub injury. “Leaf or limb rub injury” means that the scarring is not smooth, not light colored, or aggregates more...

7 CFR 51.1220 - Leaf or limb rub injury.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 2 2012-01-01 2012-01-01 false Leaf or limb rub injury. 51.1220 Section 51.1220... STANDARDS) United States Standards for Grades of Peaches Definitions § 51.1220 Leaf or limb rub injury. “Leaf or limb rub injury” means that the scarring is not smooth, not light colored, or aggregates more...

The relationship between buccofacial and limb apraxia.

PubMed

Raade, A S; Rothi, L J; Heilman, K M

1991-07-01

There are at least two possible models depicting the relationship between buccofacial and limb apraxia. First, apraxia can be viewed as a unitary motor disorder which transcends the output modalities of both buccofacial and limb output. A high degree of similarity between the two types of apraxia would support this model. Alternatively, the relationship between buccofacial and limb apraxia may not include a unitary mechanism. The presence of quantitative and qualitative differences between buccofacial and limb performance would support this nonunitary model. The results of the present study support the nonunitary model.

cis-Regulatory Mutations Are a Genetic Cause of Human Limb Malformations

PubMed Central

VanderMeer, Julia E.; Ahituv, Nadav

2011-01-01

The underlying mutations that cause human limb malformations are often difficult to determine, particularly for limb malformations that occur as isolated traits. Evidence from a variety of studies shows that cis-regulatory mutations, specifically in enhancers, can lead to some of these isolated limb malformations. Here, we provide a review of human limb malformations that have been shown to be caused by enhancer mutations and propose that cis-regulatory mutations will continue to be identified as the cause of additional human malformations as our understanding of regulatory sequences improves. PMID:21509892

Method and apparatus for simulating gravitational forces on a living organism

NASA Technical Reports Server (NTRS)

Thornton, W. E. (Inventor)

1983-01-01

A method and apparatus for simulating gravitational forces on a living organism wherein a series of negative pressures are externally applied to successive length-wise sections of a lower limb of the organism. The pressures decreasing progressively with distance of said limb sections from the heart of the organism. A casing defines a chamber adapted to contain the limb of the organism and is rigidified to resist collapse upon the application of negative pressures to the interior of the chamber. Seals extend inwardly from the casing for effective engagement with the limb of the organism and, in cooperation with the limb, subdivide the chamber into a plurality of compartments each in negative pressure communicating relation with the limb.

Warfarin-induced Venous Limb Gangrene

PubMed Central

Grim Hostetler, Sarah; Sopkovich, Jennifer; Dean, Steven

2012-01-01

Warfarin is a commonly used anticoagulant that has been associated with several significant cutaneous side effects, most notably warfarin-induced skin necrosis. A lesser known adverse reaction to warfarin is warfarin-induced venous limb gangrene. Both cutaneous adverse effects share the same pathophysiology, but are clinically quite different. The majority of cases of warfarin-induced venous limb gangrene has been in patients with cancer or heparin-induced thrombocytopenia. However, other hypercoagulable disease states, such as the antiphospholipid antibody syndrome, can be associated with venous limb gangrene. In order to increase recognition of this important condition, the authors report a case of warfarin-induced venous limb gangrene in a patient with presumed antiphospholipid antibody syndrome and review the literature on warfarin-induced venous limb gangrene. PMID:23198012

Characterization of interfacial socket pressure in transhumeral prostheses: A case series.

PubMed

Schofield, Jonathon S; Schoepp, Katherine R; Williams, Heather E; Carey, Jason P; Marasco, Paul D; Hebert, Jacqueline S

2017-01-01

One of the most important factors in successful upper limb prostheses is the socket design. Sockets must be individually fabricated to arrive at a geometry that suits the user's morphology and appropriately distributes the pressures associated with prosthetic use across the residual limb. In higher levels of amputation, such as transhumeral, this challenge is amplified as prosthetic weight and the physical demands placed on the residual limb are heightened. Yet, in the upper limb, socket fabrication is largely driven by heuristic practices. An analytical understanding of the interactions between the socket and residual limb is absent in literature. This work describes techniques, adapted from lower limb prosthetic research, to empirically characterize the pressure distribution occurring between the residual limb and well-fit transhumeral prosthetic sockets. A case series analyzing the result of four participants with transhumeral amputation is presented. A Tekscan VersaTek pressure measurement system and FaroArm Edge coordinate measurement machine were employed to capture socket-residual limb interface pressures and geometrically register these values to the anatomy of participants. Participants performed two static poses with their prosthesis under two separate loading conditions. Surface pressure maps were constructed from the data, highlighting pressure distribution patterns, anatomical locations bearing maximum pressure, and the relative pressure magnitudes. Pressure distribution patterns demonstrated unique characteristics across the four participants that could be traced to individual socket design considerations. This work presents a technique that implements commercially available tools to quantitatively characterize upper limb socket-residual limb interactions. This is a fundamental first step toward improved socket designs developed through informed, analytically-based design tools.

Characterization of interfacial socket pressure in transhumeral prostheses: A case series

PubMed Central

Schoepp, Katherine R.; Williams, Heather E.; Carey, Jason P.; Marasco, Paul D.

2017-01-01

One of the most important factors in successful upper limb prostheses is the socket design. Sockets must be individually fabricated to arrive at a geometry that suits the user’s morphology and appropriately distributes the pressures associated with prosthetic use across the residual limb. In higher levels of amputation, such as transhumeral, this challenge is amplified as prosthetic weight and the physical demands placed on the residual limb are heightened. Yet, in the upper limb, socket fabrication is largely driven by heuristic practices. An analytical understanding of the interactions between the socket and residual limb is absent in literature. This work describes techniques, adapted from lower limb prosthetic research, to empirically characterize the pressure distribution occurring between the residual limb and well-fit transhumeral prosthetic sockets. A case series analyzing the result of four participants with transhumeral amputation is presented. A Tekscan VersaTek pressure measurement system and FaroArm Edge coordinate measurement machine were employed to capture socket-residual limb interface pressures and geometrically register these values to the anatomy of participants. Participants performed two static poses with their prosthesis under two separate loading conditions. Surface pressure maps were constructed from the data, highlighting pressure distribution patterns, anatomical locations bearing maximum pressure, and the relative pressure magnitudes. Pressure distribution patterns demonstrated unique characteristics across the four participants that could be traced to individual socket design considerations. This work presents a technique that implements commercially available tools to quantitatively characterize upper limb socket-residual limb interactions. This is a fundamental first step toward improved socket designs developed through informed, analytically-based design tools. PMID:28575012

Limb-girdle muscular dystrophy subtypes: First-reported cohort from northeastern China

PubMed Central

Mahmood, Omar Abdulmonem; Jiang, Xinmei; Zhang, Qi

2013-01-01

The relative frequencies of different subtypes of limb-girdle muscular dystrophies vary widely among different populations. We estimated the percentage of limb-girdle muscular dystrophy subtypes in Chinese people based on 68 patients with limb-girdle muscular dystrophy from the Myology Clinic, Neurology Department, First Hospital of Jilin University, China. A diagnosis of calpainopathy was made in 12 cases (17%), and dysferlin deficiency in 10 cases (15%). Two biopsies revealed α-sarcoglycan deficiency (3%), and two others revealed a lack of caveolin-3 (3%). A diagnosis of unclassified limb-girdle muscular dystrophy was made in the remaining patients (62%). The appearances of calpain 3- and dysferlin-deficient biopsies were similar, though rimmed vacuoles were unique to dysferlinopathy, while inflammatory infiltrates were present in both these limb-girdle muscular dystrophy type 2D biopsies. Macrophages were detected in seven dysferlinopathy biopsies. The results of this study suggest that the distribution of limb-girdle muscular dystrophy subtypes in the Han Chinese population is similar to that reported in the West. The less necrotic, regenerating and inflammatory appearance of limb-girdle muscular dystrophy type 2A, but with more lobulated fibers, supports the idea that calpainopathy is a less active, but more chronic disease than dysferlinopathy. Unusual features indicated an extended limb-girdle muscular dystrophy disease spectrum. The use of acid phosphatase stain should be considered in suspected dysferlinopathies. To the best of our knowledge, this is the first report to define the relative proportions of the various forms of limb-girdle muscular dystrophy in China, based on protein testing. PMID:25206500

Ectopic Fgf signaling induces the intercalary response in developing chicken limb buds.

PubMed

Makanae, Aki; Satoh, Akira

2018-01-01

Intercalary pattern formation is an important regulatory step in amphibian limb regeneration. Amphibian limb regeneration is composed of multiple steps, including wounding, blastema formation, and intercalary pattern formation. Attempts have been made to transfer insights from regeneration-competent animals to regeneration-incompetent animalsat each step in the regeneration process. In the present study, we focused on the intercalary mechanism in chick limb buds. In amphibian limb regeneration, a proximodistal axis is organized as soon as a regenerating blastema is induced. Intermediate structures are subsequently induced (intercalated) between the established proximal and distal identities. Intercalary tissues are derived from proximal tissues. Fgf signaling mediates the intercalary response in amphibian limb regeneration. We attempted to transfer insights into intercalary regeneration from amphibian models to the chick limb bud. The zeugopodial part was dissected out, and the distal and proximal parts were conjunct at st. 24. Delivering ectopic Fgf2 + Fgf8 between the distal and proximal parts resulted in induction of zeugopodial elements. Examination of HoxA11 expression, apoptosis, and cell proliferation provides insights to compare with those in the intercalary mechanism of amphibian limb regeneration. Furthermore, the cellular contribution was investigated in both the chicken intercalary response and that of axolotl limb regeneration. We developed new insights into cellular contribution in amphibian intercalary regeneration, and found consistency between axolotl and chicken intercalary responses. Our findings demonstrate that the same principal of limb regeneration functions between regeneration-competent and -incompetent animals. In this context, we propose the feasibility of the induction of the regeneration response in amniotes.

Reasonable classical concepts in human lower limb anatomy from the viewpoint of the primitive persistent sciatic artery and twisting human lower limb.

PubMed

Kawashima, Tomokazu; Sasaki, Hiroshi

2010-11-01

The main aim of this review is (1) to introduce the two previous studies we published human lower limb anatomy based on the conventional macroscopic anatomical [corrected] criteria with hazardous recognition of this description, (2) to activate the discussion whether the limb homology exists, and (3) to contribute to future study filling the gap between the gross anatomy and embryology. One of the topics we discussed was the human persistent sciatic artery. To date, numerous human cases of persistent sciatic artery have been reported in which the anomalous artery was present in the posterior compartment of the thigh alongside the sciatic nerve. As one of the important criteria for assessing the human primitive sciatic artery, its ventral arterial position with respect to the sciatic nerve is reasonable based on the initial positional relationship between ventral arterial and dorsal nervous systems and comparative anatomical findings. We also discuss ways of considering the topography of muscles of the lower limb and their innervations compared to those of the upper limb. We propose a schema of the complex anatomical characteristics of the lower limb based on the vertebrate body plan. According to this reasonable schema, the twisted anatomy of the lower limb can be understood more easily. These two main ideas discussed in this paper will be useful for further understanding of the anatomy of the lower limb and as a first step for future. We hope that the future study in lower limb will be further developed by both viewpoints of the classical gross anatomy and recent embryology.

Phase II Pragmatic Randomized Controlled Trial of Patient-Led Therapies (Mirror Therapy and Lower-Limb Exercises) During Inpatient Stroke Rehabilitation.

PubMed

Tyson, Sarah; Wilkinson, Jack; Thomas, Nessa; Selles, Ruud; McCabe, Candy; Tyrrell, Pippa; Vail, Andy

2015-10-01

Patient-led therapy has the potential to increase the amount of therapy patients undertake during stroke rehabilitation and to enhance recovery. Our objective was to assess the feasibility and acceptability of 2 patient-led therapies during the acute stages of stroke care: mirror therapy for the upper limb and lower-limb exercises for the lower limb. This was a blind assessed, multicenter, pragmatic randomized controlled trial of patient-led upper-limb mirror therapy and patient-led lower leg exercises. Stroke survivors with upper and lower limb limitations, undergoing inpatient rehabilitation and able to consent were recruited at least 1 week poststroke. Both interventions proved feasible, with >90% retention. No serious adverse events were reported. Both groups did less therapy than recommended; typically 5 to 15 minutes for 7 days or less. Participants receiving mirror therapy (n = 63) tended to do less practice than those doing lower-limb exercises (n = 31). Those with neglect did 69% less mirror therapy than those without (P = .02), which was not observed in the exercise group. Observed between-group differences were modest but neglect, upper-limb strength, and dexterity showed some improvement in the mirror therapy group. No changes were seen in the lower-limb group. Both patient-led mirror therapy and lower-limb exercises during inpatient stroke care are safe, feasible, and acceptable and warrant further investigation. Practice for 5 to 15 minutes for 7 days is a realistic prescription unless strategies to enhance adherence are included. © The Author(s) 2015.

Progress Toward Optimizing Prosthetic Socket Fit and Suspension Using Elevated Vacuum to Promote Residual Limb Health.

PubMed

Wernke, Matthew M; Schroeder, Ryan M; Haynes, Michael L; Nolt, Lonnie L; Albury, Alexander W; Colvin, James M

2017-07-01

Objective: Prosthetic sockets are custom made for each amputee, yet there are no quantitative tools to determine the appropriateness of socket fit. Ensuring a proper socket fit can have significant effects on the health of residual limb soft tissues and overall function and acceptance of the prosthetic limb. Previous work found that elevated vacuum pressure data can detect movement between the residual limb and the prosthetic socket; however, the correlation between the two was specific to each user. The overall objective of this work is to determine the relationship between elevated vacuum pressure deviations and prosthetic socket fit. Approach: A tension compression machine was used to apply repeated controlled forces onto a residual limb model with sockets of different internal volume. Results: The vacuum pressure-displacement relationship was dependent on socket fit. The vacuum pressure data were sensitive enough to detect differences of 1.5% global volume and can likely detect differences even smaller. Limb motion was reduced as surface area of contact between the limb model and socket was maximized. Innovation: The results suggest that elevated vacuum pressure data provide information to quantify socket fit. Conclusions: This study provides evidence that the use of elevated vacuum pressure data may provide a method for prosthetists to quantify and monitor socket fit. Future studies should investigate the relationship between socket fit, limb motion, and limb health to define optimal socket fit parameters.

[Range of Hip Joint Motion and Weight of Lower Limb Function under 3D Dynamic Marker].

PubMed

Xia, Q; Zhang, M; Gao, D; Xia, W T

2017-12-01

To explore the range of reasonable weight coefficient of hip joint in lower limb function. When the hip joints of healthy volunteers under normal conditions or fixed at three different positions including functional, flexed and extension positions, the movements of lower limbs were recorded by LUKOtronic motion capture and analysis system. The degree of lower limb function loss was calculated using Fugl-Meyer lower limb function assessment form when the hip joints were fixed at the aforementioned positions. One-way analysis of variance and Tamhane's T2 method were used to proceed statistics analysis and calculate the range of reasonable weight coefficient of hip joint. There were significant differences between the degree of lower limb function loss when the hip joints fixed at flexed and extension positions and at functional position. While the differences between the degree of lower limb function loss when the hip joints fixed at flexed position and extension position had no statistical significance. In 95% confidence interval, the reasonable weight coefficient of hip joint in lower limb function was between 61.05% and 73.34%. Expect confirming the reasonable weight coefficient, the effects of functional and non-functional positions on the degree of lower limb function loss should also be considered for the assessment of hip joint function loss. Copyright© by the Editorial Department of Journal of Forensic Medicine

Robotic touch shifts perception of embodiment to a prosthesis in targeted reinnervation amputees

PubMed Central

Kim, Keehoon; Colgate, James Edward; Peshkin, Michael A.; Kuiken, Todd A.

2011-01-01

Existing prosthetic limbs do not provide amputees with cutaneous feedback. Tactile feedback is essential to intuitive control of a prosthetic limb and it is now clear that the sense of body self-identification is also linked to cutaneous touch. Here we have created an artificial sense of touch for a prosthetic limb by coupling a pressure sensor on the hand through a robotic stimulator to surgically redirected cutaneous sensory nerves (targeted reinnervation) that once served the lost limb. We hypothesize that providing physiologically relevant cutaneous touch feedback may help an amputee incorporate an artificial limb into his or her self image. To investigate this we used a robotic touch interface coupled with a prosthetic limb and tested it with two targeted reinnervation amputees in a series of experiments fashioned after the Rubber Hand Illusion. Results from both subjective (self-reported) and objective (physiological) measures of embodiment (questionnaires, psychophysical temporal order judgements and residual limb temperature measurements) indicate that returning physiologically appropriate cutaneous feedback from a prosthetic limb drives a perceptual shift towards embodiment of the device for these amputees. Measurements provide evidence that the illusion created is vivid. We suggest that this may help amputees to more effectively incorporate an artificial limb into their self image, providing the possibility that a prosthesis becomes not only a tool, but also an integrated body part. PMID:21252109

Variables Affecting the Amputees' Reactions Artificial Limbs in the Kingdom of Jordan

ERIC Educational Resources Information Center

Al-Adwan, Mezyed; Najjar, Yahya; Hdaib, Maha; Al-Khateeb, Monadel

2017-01-01

Amputee reaction to artificial limb is an important issue faces amputated individuals and the team who delivers services to these individuals. Although some individuals using artificial limb accept it, some others do not. There are several factors that may make it difficult to accept the artificial limb for a long time. The aim of this study is to…

Cut your losses: self-amputation of injured limbs increases survival.

PubMed

Emberts, Zachary; Miller, Christine W; Kiehl, Daniel; St Mary, Colette M

2017-01-01

Autotomy, self-induced limb loss, is an extreme trait observed throughout the animal kingdom; lizards drop their tails, crickets release their legs, and crabs drop their claws. These repeated evolutionary origins suggest that autotomy is adaptive. Yet, we do not have a firm understanding of the selective pressures that promote and maintain this extreme trait. Although multiple adaptive hypotheses exist, research has generally focused on autotomy's adaptive value as a form of predator escape. However, autotomy could also be selected to reduce the cost of an injured limb, which we investigate here. Previously, this alternative hypothesis has been challenging to directly test because when an injury occurs on an autotomizable limb, that limb is almost always dropped (i.e., autotomy is behaviorally fixed within populations). Recently, however, we have identified a species, Narnia femorata (Insecta: Hemiptera: Coreidae), where some individuals autotomize limbs in response to injury, but some do not. This natural variation allowed us to investigate both the survival costs of retaining an injured limb and the benefits of autotomizing it. In this study, we find a positive association between autotomizing injured limbs and survival, thereby quantifying a new and likely widespread benefit of autotomy-reducing the cost of injury.

Cut your losses: self-amputation of injured limbs increases survival

PubMed Central

Miller, Christine W; Kiehl, Daniel; St. Mary, Colette M

2017-01-01

Abstract Autotomy, self-induced limb loss, is an extreme trait observed throughout the animal kingdom; lizards drop their tails, crickets release their legs, and crabs drop their claws. These repeated evolutionary origins suggest that autotomy is adaptive. Yet, we do not have a firm understanding of the selective pressures that promote and maintain this extreme trait. Although multiple adaptive hypotheses exist, research has generally focused on autotomy’s adaptive value as a form of predator escape. However, autotomy could also be selected to reduce the cost of an injured limb, which we investigate here. Previously, this alternative hypothesis has been challenging to directly test because when an injury occurs on an autotomizable limb, that limb is almost always dropped (i.e., autotomy is behaviorally fixed within populations). Recently, however, we have identified a species, Narnia femorata (Insecta: Hemiptera: Coreidae), where some individuals autotomize limbs in response to injury, but some do not. This natural variation allowed us to investigate both the survival costs of retaining an injured limb and the benefits of autotomizing it. In this study, we find a positive association between autotomizing injured limbs and survival, thereby quantifying a new and likely widespread benefit of autotomy—reducing the cost of injury. PMID:29622925

Isolated limb infusion with fotemustine after dacarbazine chemosensitisation for inoperable loco-regional melanoma recurrence.

PubMed

Bonenkamp, J J; Thompson, J F; de Wilt, J H; Doubrovsky, A; de Faria Lima, R; Kam, P C A

2004-12-01

Isolated limb infusion (ILI) is a simple yet effective alternative to conventional isolated limb perfusion for the treatment of advanced melanoma of the extremities. The study group comprised 13 patients with very advanced limb disease who had failed to achieve a satisfactory response to one or more ILIs with melphalan, and in whom amputation was the only other realistic treatment option. The aim of this study was to evaluate the efficacy and toxicity of ILI with fotemustine after systemic chemosensitisation with dacarbazine (DTIC). Complete remission was achieved in four patients and partial remission in eight patients, with a median response duration of 3 months. Limb salvage was achieved in five of 12 assessable patients (42%). Limb toxicity peaked 9 days after ILI; two patients experienced Wieberdink grade IV (severe) toxicity and four patients had grade V toxicity (requiring early amputation). ILI with fotemustine after DTIC chemosensitisation can be successful when gross limb disease has not been controlled by one or more ILIs with melphalan. However, it cannot be recommended as a routine method of treatment for advanced melanoma of the extremities because of the high incidence of severe limb toxicity.

Interlimb relation during the double support phase of gait: an electromyographic, mechanical and energy-based analysis.

PubMed

Sousa, Andreia S P; Silva, Augusta; Tavares, João Manuel R S

2013-03-01

The purpose of this study is to analyse the interlimb relation and the influence of mechanical energy on metabolic energy expenditure during gait. In total, 22 subjects were monitored as to electromyographic activity, ground reaction forces and VO2 consumption (metabolic power) during gait. The results demonstrate a moderate negative correlation between the activity of tibialis anterior, biceps femoris and vastus medialis of the trailing limb during the transition between mid-stance and double support and that of the leading limb during double support for the same muscles, and between these and gastrocnemius medialis and soleus of the trailing limb during double support. Trailing limb soleus during the transition between mid-stance and double support was positively correlated to leading limb tibialis anterior, vastus medialis and biceps femoris during double support. Also, the trailing limb centre of mass mechanical work was strongly influenced by the leading limbs, although only the mechanical power related to forward progression of both limbs was correlated to metabolic power. These findings demonstrate a consistent interlimb relation in terms of electromyographic activity and centre of mass mechanical work, being the relations occurred in the plane of forward progression the more important to gait energy expenditure.

Stance-phase force on the opposite limb dictates swing-phase afferent presynaptic inhibition during locomotion

PubMed Central

Hayes, Heather Brant; Chang, Young-Hui

2012-01-01

Presynaptic inhibition is a powerful mechanism for selectively and dynamically gating sensory inputs entering the spinal cord. We investigated how hindlimb mechanics influence presynaptic inhibition during locomotion using pioneering approaches in an in vitro spinal cord–hindlimb preparation. We recorded lumbar dorsal root potentials to measure primary afferent depolarization-mediated presynaptic inhibition and compared their dependence on hindlimb endpoint forces, motor output, and joint kinematics. We found that stance-phase force on the opposite limb, particularly at toe contact, strongly influenced the magnitude and timing of afferent presynaptic inhibition in the swinging limb. Presynaptic inhibition increased in proportion to opposite limb force, as well as locomotor frequency. This form of presynaptic inhibition binds the sensorimotor states of the two limbs, adjusting sensory inflow to the swing limb based on forces generated by the stance limb. Functionally, it may serve to adjust swing-phase sensory transmission based on locomotor task, speed, and step-to-step environmental perturbations. PMID:22442562

[Prevention of recurrent varicose veins after surgery caused by phenomenon of neovascularization].

PubMed

Kas'ian, D A; Gutsu, E V; Ivanov, V A; Kuliuk, V S; Dontsu, I I

2010-01-01

The aim of study was to evaluate the effectiveness of surgical "barrier techniques" in prevention of phenomenon of inguinal neovascularization in patients with varicose veins of lower limbs. There were 68 patients (80 limbs) treated with flush ligation of saphenofemoral junction, stripping of great saphenous vein and avulsion of varicosities. Patients were divided in three groups: I (no "barrier techniques")--40 limbs; II (anatomical barrier)--20 limbs and III (synthetic barrier)--20 limbs. Duplex ultrasound was performed at interval of 24 months postoperatively. Signs of neovascularization were found more frequently in group I--22.5% of limbs vs 7.5% of limbs in patients with utilization of "barrier techniques". There were types B1, B2a and B2b of neovascularization only, according to Fischer classification. We conclude that use of a "barrier techniques", either anatomic or synthetic, is associated with a decreased incidence of neovascularization at the level of the saphenofemoral junction compared with a control group.

Msx genes are important apoptosis effectors downstream of the Shh/Gli3 pathway in the limb.

PubMed

Lallemand, Yvan; Bensoussan, Vardina; Cloment, Cécile Saint; Robert, Benoît

2009-07-15

In tetrapods, the anteroposterior (AP) patterning of the limb is under the control of the antagonistic activities of the secreted factor Sonic hedgehog (Shh) and Gli3R, the truncated repressor form of the transcription factor Gli3. In this report, we show that Msx1 and Msx2 are targets and downstream effectors of Gli3R. Consequently, in Shh null mutants, Msx genes are overexpressed and, furthermore, partially responsible for the limb phenotype. This is exemplified by the fact that reducing Msx activity in Shh mutants partially restores a normal limb development. Finally, we show that the main action of the Msx genes, in both normal and Shh(-/-) limb development, is to control cell death in the mesenchyme. We propose that, in the limb, Msx genes act downstream of the Shh/Gli3 pathway by transducing BMP signaling and that, in the absence of Shh signaling, their deregulation contributes to the extensive apoptosis that impairs limb development.

Attenuated sensing of SHH by Ptch1 underlies evolution of bovine limbs.

PubMed

Lopez-Rios, Javier; Duchesne, Amandine; Speziale, Dario; Andrey, Guillaume; Peterson, Kevin A; Germann, Philipp; Unal, Erkan; Liu, Jing; Floriot, Sandrine; Barbey, Sarah; Gallard, Yves; Müller-Gerbl, Magdalena; Courtney, Andrew D; Klopp, Christophe; Rodriguez, Sabrina; Ivanek, Robert; Beisel, Christian; Wicking, Carol; Iber, Dagmar; Robert, Benoit; McMahon, Andrew P; Duboule, Denis; Zeller, Rolf

2014-07-03

The large spectrum of limb morphologies reflects the wide evolutionary diversification of the basic pentadactyl pattern in tetrapods. In even-toed ungulates (artiodactyls, including cattle), limbs are adapted for running as a consequence of progressive reduction of their distal skeleton to symmetrical and elongated middle digits with hoofed phalanges. Here we analyse bovine embryos to establish that polarized gene expression is progressively lost during limb development in comparison to the mouse. Notably, the transcriptional upregulation of the Ptch1 gene, which encodes a Sonic hedgehog (SHH) receptor, is disrupted specifically in the bovine limb bud mesenchyme. This is due to evolutionary alteration of a Ptch1 cis-regulatory module, which no longer responds to graded SHH signalling during bovine handplate development. Our study provides a molecular explanation for the loss of digit asymmetry in bovine limb buds and suggests that modifications affecting the Ptch1 cis-regulatory landscape have contributed to evolutionary diversification of artiodactyl limbs.

Upper limb load as a function of repetitive task parameters: part 1--a model of upper limb load.

PubMed

Roman-Liu, Danuta

2005-01-01

The aim of the study was to develop a theoretical indicator of upper limb musculoskeletal load based on repetitive task parameters. As such the dimensionless parameter, Integrated Cycle Load (ICL) was accepted. It expresses upper limb load which occurs during 1 cycle. The indicator is based on a model of a repetitive task, which consists of a model of the upper limb, a model of basic types of upper limb forces and a model of parameters of a repetitive task such as length of the cycle, length of periods of the cycle and external force exerted during each of the periods of the cycle. Calculations of the ICL parameter were performed for 12 different variants of external load characterised by different values of repetitive task parameters. A comparison of ICL, which expresses external load with a physiological indicator of upper limb load, is presented in Part 2 of the paper.

Upper-limb motor and sensory function in patients with hip fracture: Comparison with community-dwelling older adults.

PubMed

Hayashi, Hiroyuki; Nakashima, Daiki; Matsuoka, Hiroka; Iwai, Midori; Nakamura, Shugo; Kubo, Ayumi; Tomiyama, Naoki

2017-11-06

Upper-limb function is important in patients with hip fracture so they can perform activities of daily living and participate in leisure activities. Upper-limb function of these patients, however, has not been thoroughly investigated. The aim of this study was to evaluate the upper-limb motor and sensory functions in patients with hip fracture by comparing these functions with those of community-dwelling older adults (control group). We compared the results of motor and sensory function tests of upper-limb function - range of motion, strength, sensibility, finger dexterity, comprehensive hand function - between patients with hip fracture (n= 32) and the control group (n= 32). Patients with hip fracture had significantly reduced grip strength, pinch strength, finger dexterity, and comprehensive hand function compared with the control group. Most upper-limb functions are impaired in the patients with hip fracture. Thus, upper-limb function of patients with hip fracture should be considered during treatment.

Age Effects on Upper Limb Kinematics Assessed by the REAplan Robot in Healthy School-Aged Children.

PubMed

Gilliaux, Maxime; Dierckx, Floriane; Vanden Berghe, Lola; Lejeune, Thierry M; Sapin, Julien; Dehez, Bruno; Stoquart, Gaëtan; Detrembleur, Christine

2015-05-01

The use of kinematics is recommended to quantitatively evaluate upper limb movements. The aims of this study were to determine the age effects on upper limb kinematics and establish norms in healthy children. Ninety-three healthy children, aged 3-12 years, participated in this study. Twenty-eight kinematic indices were computed from four tasks. Each task was performed with the REAplan, a distal effector robotic device that allows upper limb displacements in the horizontal plane. Twenty-four of the 28 indices showed an improvement during childhood. Indeed, older children showed better upper limb movements. This study was the first to use a robotic device to show the age effects on upper limb kinematics and establish norms in healthy children.

Postural asymmetries in response to holding evenly and unevenly distributed loads during self-selected stance.

PubMed

Haddad, Jeffrey M; Rietdyk, Shirley; Ryu, Joong Hyun; Seaman, Jessica M; Silver, Tobin A; Kalish, Julia A; Hughes, Charmayne M L

2011-01-01

The authors examined postural asymmetries during quiet stance and while holding evenly or unevenly distributed loads. Right-hand dominant subjects preferentially loaded their right lower limb when holding no load or a load evenly distributed in both hands, but no differences in center of pressure (CoP) were observed between the left and right limbs. However, longer CoP displacement was observed under the preferentially loaded limb, which may reflect a functional asymmetry that allows quick movement of one limb in response to a potential perturbation. When a load was held only in the nondominant hand, sample entropy decreased in the left (loaded) limb but increased in the right (unloaded) limb, suggesting the unloaded foot compensated for a loss of control flexibility in the loaded foot.

A limb action detector enabling people with multiple disabilities to control environmental stimulation through limb action with a Nintendo Wii Remote Controller.

PubMed

Shih, Ching-Hsiang; Chang, Man-Ling; Shih, Ching-Tien

2010-01-01

This study assessed whether two persons with multiple disabilities would be able to control environmental stimulation using limb action with a Nintendo Wii Remote Controller and a newly developed limb action detection program (LADP, i.e., a new software program that turns a Wii Remote Controller into a precise limb action detector). This study was carried out according to an ABAB sequence in which A represented baseline and B represented intervention phases. Data showed that both participants significantly increased their target response, thus increasing the level of environmental stimulation by activating the control system through limb action, during the intervention phases. Practical and developmental implications of the findings are discussed. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

A Special Golden Curve in Human Upper Limbs' Length Proportion: A Functional Partition Which Is Different from Anatomy.

PubMed

Wang, Nan; Ma, Jie; Jin, Dan; Yu, Bin

2017-01-01

Aim . The purpose of this study was to investigate the relationship between upper limbs' three functional partitions and the golden curve. Materials and Methods . We measured 30 subjects' right or left upper limb data and investigate the relationship between them and the golden curve by use of SPSS version 20.0 statistical software (SPSS, Inc., Chicago, Illinois), one-sample t -test. Results . There are four points on human's upper limbs which have no difference with the four points on the golden curve. And there is one point of which the difference is obvious. But we still could draw the conclusion that human upper limbs are accordant with the golden curve. Conclusion . Human upper limbs are accordant with the golden curve.

Sex and the single (-eared) female: leg function, limb autotomy and mating history trade-offs in field crickets (Gryllus bimaculatus)

PubMed Central

Bateman, Philip W; Fleming, Patricia A

2005-01-01

Both male and female field crickets (Gryllus bimaculatus) autotomize front (tympanal) limbs more slowly than hind limbs. Arguably, this pattern could reflect possible differences in the mechanism of limb autotomy. However, we demonstrate that, for females, limb autotomy is also dependent on their mating status: virgin females autotomize front legs significantly more slowly than mated females. This response suggests a central control for leg autotomy in these animals, and less readiness to autotomize a front leg, possibly because the tympanum is crucial for mate location. PMID:17148319

Differentiation of cartilaginous anlagen in entire embryonic mouse limbs cultured in a rotating bioreactor

NASA Astrophysics Data System (ADS)

Montufar-Solis, D.; Oakley, C. R.; Jefferson, Y.; Duke, P. J.

2003-10-01

Mechanisms involved in development of the embryonic limb have remained the same throughout eons of genetic and environmental evolution under Earth gravity (lg). During the spaceflight era it has been of interest to explore the ancient theory that form of the skeleton develops in response to gravity, and that changes in gravitational forces can change the developmental pattern of the limb. This has been shown in vivo and in vitro, allowing the hypergravity of centrifugation and microgravity of space to be used as tools to increase our knowledge of limb development. In recapitulations of spaceflight experiments, premetatarsals were cultured in suspension in a bioreactor, and found to be shorter and less differentiated than those cultured in standard culture dishes. This study only measured length of the metatarsals, and did not account for possible changes due to the skeletal elements having a more in vivo 3D shape while in suspension vs. flattened tissues compressed by their own weight. A culture system with an outcome closer to in vivo and that supports growth of younger limb buds than traditional systems will allow studies of early Hox gene expression, and contribute to the understanding of very early stages of development. The purpose of the current experiment was to determine if entire limb buds could be cultured in the bioreactor, and to compare the growth and differentiation with that of culturing in a culture dish system. Fore and hind limbs from E11-E13 ICR mouse embryos were cultured for six days, either in the bioreactor or in center-well organ culture dishes, fixed, and embedded for histology. E13 specimens grown in culture dishes were flat, while bioreactor culture specimens had a more in vivo-like 3D limb shape. Sections showed excellent cartilage differentiation in both culture systems, with more cell maturation, and hypertrophy in the specimens cultured in the bioreactor. Younger limb buds fused together during culture, so an additional set of El 1.5 limb buds was cultured with and without encapsulation in alginate prior to culturing in the bioreactor. Encapsulated limbs grown in the bioreactor did not fuse together, but developed only the more proximal elements while limbs grown in culture dishes formed proximal and distal elements. Alginate encapsulation may have reduced oxygenation to the progress zone of the developing limb bud resulting in lack of development of the more distal elements. These results show that the bioreactor supports growth and differentiation of skeletal elements in entire E13 limb buds, and that a method to culture younger limb buds without fusing together needs to be developed if any morphometric analysis is to be performed.

Real-time patient-specific finite element analysis of internal stresses in the soft tissues of a residual limb: a new tool for prosthetic fitting.

PubMed

Portnoy, S; Yarnitzky, G; Yizhar, Z; Kristal, A; Oppenheim, U; Siev-Ner, I; Gefen, A

2007-01-01

Fitting of a prosthetic socket is a critical stage in the process of rehabilitation of a trans-tibial amputation (TTA) patient, since a misfit may cause pressure ulcers or a deep tissue injury (DTI: necrosis of the muscle flap under intact skin) in the residual limb. To date, prosthetic fitting typically depends on the subjective skills of the prosthetist, and is not supported by biomedical instrumentation that allows evaluation of the quality of fitting. Specifically, no technology is presently available to provide real-time continuous information on the internal distribution of mechanical stresses in the residual limb during fitting of the prosthesis, or while using it and this severely limits patient evaluations. In this study, a simplified yet clinically oriented patient-specific finite element (FE) model of the residual limb was developed for real-time stress analysis. For this purpose we employed a custom-made FE code that continuously calculates internal stresses in the residual limb, based on boundary conditions acquired in real-time from force sensors, located at the limb-prosthesis interface. Validation of the modeling system was accomplished by means of a synthetic phantom of the residual limb, which allowed simultaneous measurements of interface pressures and internal stresses. Human studies were conducted subsequently in five TTA patients. The dimensions of bones and soft tissues were obtained from X-rays of the residual limb of each patient. An indentation test was performed in order to obtain the effective elastic modulus of the soft tissues of the residual limb. Seven force sensors were placed between the residual limb and the prosthetic liner, and subjects walked on a treadmill during analysis. Generally, stresses under the shinbones were approximately threefold higher than stresses at the soft tissues behind the bones. Usage of a thigh corset decreased the stresses in the residual limb during gait by approximately 80%. Also, the stresses calculated during the trial of a subject who complained about pain and discomfort were the highest, confirming that his socket was not adequately fitted. We conclude that real-time patient-specific FE analysis of internal stresses in deep soft tissues of the residual limb in TTA patients is feasible. This method is promising for improving the fitting of prostheses in the clinical setting and for protecting the residual limb from pressure ulcers and DTI.

Total hip arthroplasty performed in patients with residual poliomyelitis: does it work?

PubMed

Yoon, Byung-Ho; Lee, Young-Kyun; Yoo, Jeong Joon; Kim, Hee Joong; Koo, Kyung-Hoi

2014-03-01

Patients with residual poliomyelitis can have advanced degenerative arthritis of the hip in the paralytic limb or the nonparalytic contralateral limb. Although THA is a treatment option for some of these patients, there are few studies regarding THA in this patient population. We therefore reviewed a group of patients with residual poliomyelitis who underwent cementless THA on either their paralytic limb or nonparalytic limb to assess (1) Harris hip scores, (2) radiographic results, including implant loosening, (3) complications, including dislocation, and (4) limb length discrepancy after recovery from surgery. From January 2000 to December 2009, 10 patients with residual poliomyelitis (10 hips, four paralytic limbs and six nonparalytic contralateral limbs) underwent THA using cementless prostheses. Harris hip scores, complications, and leg length discrepancy were determined by chart review, and confirmed by questionnaire and examination; radiographs were reviewed by two observers for this study. Followup was available for all 10 patients at a minimum of 3 years (median, 7 years; range, 3.4-13 years). Surgery was done at the same side of the paralytic limb in four hips and contralateral to the paralytic limb in six. All patients had pain relief and improvement in function; the Harris hip score improved from mean of 68 preoperatively to 92 at last followup (p = 0.043). However, only three patients had complete pain relief. One hip dislocated, which was treated successfully with closed reduction and a hip spica cast for 2 months. There was no loosening or osteolysis in this series. Leg length discrepancy improved after the index operation, but only in the THAs performed in the paralytic limbs. Cementless THA may be suitable for painful hips in adult patients with residual poliomyelitis. Nonetheless, these patients should be informed of the possibility of mild residual pain and persistent leg length discrepancy, particularly patients whose THA is performed on the limb that was not affected by polio (ie, the nonparalytic contralateral limb). Level IV, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Limb Symmetry Indexes Can Overestimate Knee Function After Anterior Cruciate Ligament Injury.

PubMed

Wellsandt, Elizabeth; Failla, Mathew J; Snyder-Mackler, Lynn

2017-05-01

Study Design Prospective cohort. Background The high risk of second anterior cruciate ligament (ACL) injuries after return to sport highlights the importance of return-to-sport decision making. Objective return-to-sport criteria frequently use limb symmetry indexes (LSIs) to quantify quadriceps strength and hop scores. Whether using the uninvolved limb in LSIs is optimal is unknown. Objectives To evaluate the uninvolved limb as a reference standard for LSIs utilized in return-to-sport testing and its relationship with second ACL injury rates. Methods Seventy athletes completed quadriceps strength and 4 single-leg hop tests before anterior cruciate ligament reconstruction (ACLR) and 6 months after ACLR. Limb symmetry indexes for each test compared involved-limb measures at 6 months to uninvolved-limb measures at 6 months. Estimated preinjury capacity (EPIC) levels for each test compared involved-limb measures at 6 months to uninvolved-limb measures before ACLR. Second ACL injuries were tracked for a minimum follow-up of 2 years after ACLR. Results Forty (57.1%) patients achieved 90% LSIs for quadriceps strength and all hop tests. Only 20 (28.6%) patients met 90% EPIC levels (comparing the involved limb at 6 months after ACLR to the uninvolved limb before ACLR) for quadriceps strength and all hop tests. Twenty-four (34.3%) patients who achieved 90% LSIs for all measures 6 months after ACLR did not achieve 90% EPIC levels for all measures. Estimated preinjury capacity levels were more sensitive than LSIs in predicting second ACL injuries (LSIs, 0.273; 95% confidence interval [CI]: 0.010, 0.566 and EPIC, 0.818; 95% CI: 0.523, 0.949). Conclusion Limb symmetry indexes frequently overestimate knee function after ACLR and may be related to second ACL injury risk. These findings raise concern about whether the variable ACL return-to-sport criteria utilized in current clinical practice are stringent enough to achieve safe and successful return to sport. Level of Evidence Prognosis, 2b. J Orthop Sports Phys Ther 2017;47(5):334-338. Epub 29 Mar 2017. doi:10.2519/jospt.2017.7285.

Different regulation of limb development by p63 transcript variants.

PubMed

Kawata, Manabu; Taniguchi, Yuki; Mori, Daisuke; Yano, Fumiko; Ohba, Shinsuke; Chung, Ung-Il; Shimogori, Tomomi; Mills, Alea A; Tanaka, Sakae; Saito, Taku

2017-01-01

The apical ectodermal ridge (AER), located at the distal end of each limb bud, is a key signaling center which controls outgrowth and patterning of the proximal-distal axis of the limb through secretion of various molecules. Fibroblast growth factors (FGFs), particularly Fgf8 and Fgf4, are representative molecules produced by AER cells, and essential to maintain the AER and cell proliferation in the underlying mesenchyme, meanwhile Jag2-Notch pathway negatively regulates the AER and limb development. p63, a transcription factor of the p53 family, is expressed in the AER and indispensable for limb formation. However, the underlying mechanisms and specific roles of p63 variants are unknown. Here, we quantified the expression of p63 variants in mouse limbs from embryonic day (E) 10.5 to E12.5, and found that ΔNp63γ was strongly expressed in limbs at all stages, while TAp63γ expression was rapidly increased in the later stages. Fluorescence-activated cell sorting analysis of limb bud cells from reporter mouse embryos at E11.5 revealed that all variants were abundantly expressed in AER cells, and their expression was very low in mesenchymal cells. We then generated AER-specific p63 knockout mice by mating mice with a null and a flox allele of p63, and Msx2-Cre mice (Msx2-Cre;p63Δ/fl). Msx2-Cre;p63Δ/fl neonates showed limb malformation that was more obvious in distal elements. Expression of various AER-related genes was decreased in Msx2-Cre;p63Δ/fl limb buds and embryoid bodies formed by p63-knockdown induced pluripotent stem cells. Promoter analyses and chromatin immunoprecipitation assays demonstrated Fgf8 and Fgf4 as transcriptional targets of ΔNp63γ, and Jag2 as that of TAp63γ. Furthermore, TAp63γ overexpression exacerbated the phenotype of Msx2-Cre;p63Δ/fl mice. These data indicate that ΔNp63 and TAp63 control limb development through transcriptional regulation of different target molecules with different roles in the AER. Our findings contribute to further understanding of the molecular network of limb development.

Limb bone morphology, bone strength, and cursoriality in lagomorphs

PubMed Central

Young, Jesse W; Danczak, Robert; Russo, Gabrielle A; Fellmann, Connie D

2014-01-01

The primary aim of this study is to broadly evaluate the relationship between cursoriality (i.e. anatomical and physiological specialization for running) and limb bone morphology in lagomorphs. Relative to most previous studies of cursoriality, our focus on a size-restricted, taxonomically narrow group of mammals permits us to evaluate the degree to which ‘cursorial specialization’ affects locomotor anatomy independently of broader allometric and phylogenetic trends that might obscure such a relationship. We collected linear morphometrics and μCT data on 737 limb bones covering three lagomorph species that differ in degree of cursoriality: pikas (Ochotona princeps, non-cursorial), jackrabbits (Lepus californicus, highly cursorial), and rabbits (Sylvilagus bachmani, level of cursoriality intermediate between pikas and jackrabbits). We evaluated two hypotheses: cursoriality should be associated with (i) lower limb joint mechanical advantage (i.e. high ‘displacement advantage’, permitting more cursorial species to cycle their limbs more quickly) and (ii) longer, more gracile limb bones, particularly at the distal segments (as a means of decreasing rotational inertia). As predicted, highly cursorial jackrabbits are typically marked by the lowest mechanical advantage and the longest distal segments, non-cursorial pikas display the highest mechanical advantage and the shortest distal segments, and rabbits generally display intermediate values for these variables. Variation in long bone robusticity followed a proximodistal gradient. Whereas proximal limb bone robusticity declined with cursoriality, distal limb bone robusticity generally remained constant across the three species. The association between long, structurally gracile limb bones and decreased maximal bending strength suggests that the more cursorial lagomorphs compromise proximal limb bone integrity to improve locomotor economy. In contrast, the integrity of distal limb bones is maintained with increasing cursoriality, suggesting that the safety factor takes priority over locomotor economy in those regions of the postcranial skeleton that experience higher loading during locomotion. Overall, these findings support the hypothesis that cursoriality is associated with a common suite of morphological adaptations across a range of body sizes and radiations. PMID:25046350

Muscle activation levels of the gluteus maximus and medius during standing hip-joint strengthening exercises using elastic-tubing resistance.

PubMed

Youdas, James W; Adams, Kady E; Bertucci, John E; Brooks, Koel J; Nelson, Meghan M; Hollman, John H

2014-02-01

No published studies have compared muscle activation levels simultaneously for the gluteus maximus and medius muscles of stance and moving limbs during standing hip-joint strengthening while using elastic-tubing resistance. To quantify activation levels bilaterally of the gluteus maximus and medius during resisted lower-extremity standing exercises using elastic tubing for the cross-over, reverse cross-over, front-pull, and back-pull exercise conditions. Repeated measures. Laboratory. 26 active and healthy people, 13 men (25 ± 3 y) and 13 women (24 ± 1 y). Subjects completed 3 consecutive repetitions of lower-extremity exercises in random order. Surface electromyographic (EMG) signals were normalized to peak activity in the maximum voluntary isometric contraction (MVIC) trial and expressed as a percentage. Magnitudes of EMG recruitment were analyzed with a 2 × 4 repeated-measures ANOVA for each muscle (α = .05). For the gluteus maximus an interaction between exercise and limb factor was significant (F3,75 = 21.5; P < .001). The moving-limb gluteus maximus was activated more than the stance limb's during the back-pull exercise (P < .001), and moving-limb gluteus maximus muscle recruitment was greater for the back-pull exercise than for the cross-over, reverse cross-over, and front-pull exercises (P < .001). For the gluteus medius an interaction between exercise and limb factor was significant (F3,75 = 3.7; P < .03). Gluteus medius muscle recruitment (% MVIC) was greater in the stance limb than moving limb when performing the front-pull exercise (P < .001). Moving-limb gluteus medius muscle recruitment was greater for the reverse cross-over exercise than for the cross-over, front-pull, and back-pull exercises (P < .001). From a clinical standpoint there is no therapeutic benefit to selectively activate the gluteus maximus and gluteus medius muscles on the stance limb by resisting sagittal- and frontal-plane hip movements on the moving limb using resistance supplied by elastic tubing.

Constraint-induced movement therapy improves upper limb activity and participation in hemiplegic cerebral palsy: a systematic review.

PubMed

Chiu, Hsiu-Ching; Ada, Louise

2016-07-01

Does constraint-induced movement therapy improve activity and participation in children with hemiplegic cerebral palsy? Does it improve activity and participation more than the same dose of upper limb therapy without restraint? Is the effect of constraint-induced movement therapy related to the duration of intervention or the age of the children? Systematic review of randomised trials with meta-analysis. Children with hemiplegic cerebral palsy with any level of motor disability. The experimental group received constraint-induced movement therapy (defined as restraint of the less affected upper limb during supervised activity practice of the more affected upper limb). The control group received no intervention, sham intervention, or the same dose of upper limb therapy. Measures of upper limb activity and participation were used in the analysis. Constraint-induced movement therapy was more effective than no/sham intervention in terms of upper limb activity (SMD 0.63, 95% CI 0.20 to 1.06) and participation (SMD 1.21, 95% CI 0.41 to 2.02). However, constraint-induced movement therapy was no better than the same dose of upper limb therapy without restraint either in terms of upper limb activity (SMD 0.05, 95% CI -0.21 to 0.32) or participation (SMD -0.02, 95% CI -0.34 to 0.31). The effect of constraint-induced movement therapy was not related to the duration of intervention or the age of the children. This review suggests that constraint-induced movement therapy is more effective than no intervention, but no more effective than the same dose of upper limb practice without restraint. PROSPERO CRD42015024665. [Chiu H-C, Ada L (2016) Constraint-induced movement therapy improves upper limb activity and participation in hemiplegic cerebral palsy: a systematic review.Journal of Physiotherapy62: 130-137]. Copyright © 2016 Australian Physiotherapy Association. Published by Elsevier B.V. All rights reserved.

Growth factors FGF8 and FGF2 and their receptor FGFR1, transcriptional factors Msx-1 and MSX-2, and apoptotic factors p19 and RIP5 participate in the early human limb development.

PubMed

Becic, Tina; Kero, Darko; Vukojevic, Katarina; Mardesic, Snjezana; Saraga-Babic, Mirna

2018-04-01

The expression pattern of fibroblast growth factors FGF8 and FGF2 and their receptor FGFR1, transcription factors MSX-1 and MSX-2, as well as cell proliferation (Ki-67) and cell death associated caspase-3, p19 and RIP5 factors were analyzed in histological sections of eight 4th-9th-weeks developing human limbs by immunohistochemistry and semi-thin sectioning. Increasing expression of all analyzed factors (except FGF8) characterized both the multilayered human apical ectodermal ridge (AER), sub-ridge mesenchyme (progress zone) and chondrocytes in developing human limbs. While cytoplasmic co-expression of MSX-1 and MSX-2 was observed in both limb epithelium and mesenchyme, p19 displayed strong cytoplasmic expression in non-proliferating cells. Nuclear expression of Ki-67 proliferating cells, and partly of MSX-1 and MSX-2 was detected in the whole limb primordium. Strong expression of factors p19 and RIP5, both in the AER and mesenchyme of human developing limbs indicates their possible involvement in control of cell senescence and cell death. In contrast to animal studies, expression of FGFR1 in the surface ectoderm and p19 in the whole limb primordium might reflect interspecies differences in limb morphology. Expression of FGF2 and downstream RIP5 gene, and transcription factors Msx-1 and MSX-2 did not show human-specific changes in expression pattern. Based on their spatio-temporal expression during human limb development, our study indicates role of FGFs and Msx genes in stimulation of cell proliferation, limb outgrowth, digit elongation and separation, and additionally MSX-2 in control of vasculogenesis. The cascade of orchestrated gene expressions, including the analyzed developmental factors, jointly contribute to the complex human limb development. Copyright © 2018 Elsevier GmbH. All rights reserved.

Visualisation of upper limb activity using spirals: A new approach to the assessment of daily prosthesis usage.

PubMed

Chadwell, Alix; Kenney, Laurence; Granat, Malcolm; Thies, Sibylle; Head, John S; Galpin, Adam

2018-02-01

Current outcome measures used in upper limb myoelectric prosthesis studies include clinical tests of function and self-report questionnaires on real-world prosthesis use. Research in other cohorts has questioned both the validity of self-report as an activity assessment tool and the relationship between clinical functionality and real-world upper limb activity. Previously, 1 we reported the first results of monitoring upper limb prosthesis use. However, the data visualisation technique used was limited in scope. Methodology development. To introduce two new methods for the analysis and display of upper limb activity monitoring data and to demonstrate the potential value of the approach with example real-world data. Upper limb activity monitors, worn on each wrist, recorded data on two anatomically intact participants and two prosthesis users over 1 week. Participants also filled in a diary to record upper limb activity. Data visualisation was carried out using histograms, and Archimedean spirals to illustrate temporal patterns of upper limb activity. Anatomically intact participants' activity was largely bilateral in nature, interspersed with frequent bursts of unilateral activity of each arm. At times when the prosthesis was worn prosthesis users showed very little unilateral use of the prosthesis (≈20-40 min/week compared to ≈350 min/week unilateral activity on each arm for anatomically intact participants), with consistent bias towards the intact arm throughout. The Archimedean spiral plots illustrated participant-specific patterns of non-use in prosthesis users. The data visualisation techniques allow detailed and objective assessment of temporal patterns in the upper limb activity of prosthesis users. Clinical relevance Activity monitoring offers an objective method for the assessment of upper limb prosthesis users' (PUs) activity outside of the clinic. By plotting data using Archimedean spirals, it is possible to visualise, in detail, the temporal patterns of upper limb activity. Further work is needed to explore the relationship between traditional functional outcome measures and real-world prosthesis activity.

Air pollution and limb defects: a matched-pairs case-control study in Taiwan.

PubMed

Lin, Yu-Ting; Lee, Yungling Leo; Jung, Chau-Ren; Jaakkola, Jouni J K; Hwang, Bing-Fang

2014-07-01

Air pollution influences the development of limb defects in animals. There is little epidemiologic evidence on the effect of prenatal air pollution exposure on the risk of limb defects. To assess the relations between exposure to ambient air pollutants and the risk of limb defects. We conducted a matched-pairs case-control study in Taiwan from 2001 through 2007. The case group consisted of 1687 limb defects and the control group was density-sampling matched one to ten based on the month and year of conception from 1510,064 live singleton newborns in 2001-2007. Adjusted conditional logistic regression models were used to estimate odds ratios per 10 ppb change for O3, NO2, 1 ppb change for SO2, 10 µg/m(3) change for PM10, and 100 ppb change for CO during the first trimester and first three gestational months. Of the specific limb defects, reduction deformities of limbs (adjusted OR=1.024, 95% CI: 1.000, 1.048) was associated with a 1 ppb increase in SO2 during weeks of 9-12 of gestation as well as the first trimester. Reduction deformities of limbs was also associated with a 10 ppb increase in O3 during weeks of 1-4 of gestation (adjusted OR=1.391, 95% CI: 1.064, 1.818) among preterm births. The present study provides evidence that exposure to outdoor air SO2 during the first trimester of pregnancy may increase the risk of limb defects. Exposure to O3 was associated with reduction deformities of limbs among preterm births. Similar levels of SO2 and O3 are encountered globally by large numbers of pregnant women. Copyright © 2014 Elsevier Inc. All rights reserved.

Genetic Interactions Between Shox2 and Hox Genes During the Regional Growth and Development of the Mouse Limb

PubMed Central

Neufeld, Stanley J.; Wang, Fan; Cobb, John

2014-01-01

The growth and development of the vertebrate limb relies on homeobox genes of the Hox and Shox families, with their independent mutation often giving dose-dependent effects. Here we investigate whether Shox2 and Hox genes function together during mouse limb development by modulating their relative dosage and examining the limb for nonadditive effects on growth. Using double mRNA fluorescence in situ hybridization (FISH) in single embryos, we first show that Shox2 and Hox genes have associated spatial expression dynamics, with Shox2 expression restricted to the proximal limb along with Hoxd9 and Hoxa11 expression, juxtaposing the distal expression of Hoxa13 and Hoxd13. By generating mice with all possible dosage combinations of mutant Shox2 alleles and HoxA/D cluster deletions, we then show that their coordinated proximal limb expression is critical to generate normally proportioned limb segments. These epistatic interactions tune limb length, where Shox2 underexpression enhances, and Shox2 overexpression suppresses, Hox-mutant phenotypes. Disruption of either Shox2 or Hox genes leads to a similar reduction in Runx2 expression in the developing humerus, suggesting their concerted action drives cartilage maturation during normal development. While we furthermore provide evidence that Hox gene function influences Shox2 expression, this regulation is limited in extent and is unlikely on its own to be a major explanation for their genetic interaction. Given the similar effect of human SHOX mutations on regional limb growth, Shox and Hox genes may generally function as genetic interaction partners during the growth and development of the proximal vertebrate limb. PMID:25217052

Genetic interactions between Shox2 and Hox genes during the regional growth and development of the mouse limb.

PubMed

Neufeld, Stanley J; Wang, Fan; Cobb, John

2014-11-01

The growth and development of the vertebrate limb relies on homeobox genes of the Hox and Shox families, with their independent mutation often giving dose-dependent effects. Here we investigate whether Shox2 and Hox genes function together during mouse limb development by modulating their relative dosage and examining the limb for nonadditive effects on growth. Using double mRNA fluorescence in situ hybridization (FISH) in single embryos, we first show that Shox2 and Hox genes have associated spatial expression dynamics, with Shox2 expression restricted to the proximal limb along with Hoxd9 and Hoxa11 expression, juxtaposing the distal expression of Hoxa13 and Hoxd13. By generating mice with all possible dosage combinations of mutant Shox2 alleles and HoxA/D cluster deletions, we then show that their coordinated proximal limb expression is critical to generate normally proportioned limb segments. These epistatic interactions tune limb length, where Shox2 underexpression enhances, and Shox2 overexpression suppresses, Hox-mutant phenotypes. Disruption of either Shox2 or Hox genes leads to a similar reduction in Runx2 expression in the developing humerus, suggesting their concerted action drives cartilage maturation during normal development. While we furthermore provide evidence that Hox gene function influences Shox2 expression, this regulation is limited in extent and is unlikely on its own to be a major explanation for their genetic interaction. Given the similar effect of human SHOX mutations on regional limb growth, Shox and Hox genes may generally function as genetic interaction partners during the growth and development of the proximal vertebrate limb. Copyright © 2014 by the Genetics Society of America.

Energy flow analysis of amputee walking shows a proximally-directed transfer of energy in intact limbs, compared to a distally-directed transfer in prosthetic limbs at push-off.

PubMed

Weinert-Aplin, R A; Howard, D; Twiste, M; Jarvis, H L; Bennett, A N; Baker, R J

2017-01-01

Reduced capacity and increased metabolic cost of walking occurs in amputees, despite advances in prosthetic componentry. Joint powers can quantify deficiencies in prosthetic gait, but do not reveal how energy is exchanged between limb segments. This study aimed to quantify these energy exchanges during amputee walking. Optical motion and forceplate data collected during walking at a self-selected speed for cohorts of 10 controls, 10 unilateral trans-tibial, 10 unilateral trans-femoral and 10 bilateral trans-femoral amputees were used to determine the energy exchanges between lower limb segments. At push-off, consistent thigh and shank segment powers were observed between amputee groups (1.12W/kg vs. 1.05W/kg for intact limbs and 0.97W/kg vs. 0.99W/kg for prosthetic limbs), and reduced prosthetic ankle power, particularly in trans-femoral amputees (3.12W/kg vs. 0.87W/kg). Proximally-directed energy exchange was observed in the intact limbs of amputees and controls, while prosthetic limbs displayed distally-directed energy exchanges at the knee and hip. This study used energy flow analysis to show a reversal in the direction in which energy is exchanged between prosthetic limb segments at push-off. This reversal was required to provide sufficient energy to propel the limb segments and is likely a direct result of the lack of push-off power at the prosthetic ankle, particularly in trans-femoral amputees, and leads to their increased metabolic cost of walking. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

The effect of lower limb rehabilitation gymnastics on postoperative rehabilitation in elderly patients with femoral shaft fracture

PubMed Central

Yang, Si-Dong; Ning, Sheng-Hua; Zhang, Li-Hong; Zhang, Ying-Ze; Ding, Wen-Yuan; Yang, Da-Long

2016-01-01

Abstract The purpose of this study was to explore the effect of lower limb rehabilitation gymnastics on postoperative rehabilitation in elderly patients with femoral shaft fracture after undergoing intramedullary nail fixation surgery. We collected medical records of elderly patients aged ≥ 60 years with femoral shaft fracture between 03/2010 and 03/2015 in Longyao County Hospital. Totally, 160 patients were identified and divided into the intervention group (n = 80) and the control group (n = 80). During the postoperative period, the intervention group received lower limb rehabilitation gymnastics treatment for 3 months, but the control group did not. All patients were routinely asked to return hospital for a check in the 1st postoperative week, as well as the 2nd week, the 1st month, and the 3rd month, after surgery. The clinical rehabilitation effect was evaluated by checking lower limb action ability, detecting the lower limb deep venous thrombosis (DVT), scoring muscle strength of quadriceps and visual analog scale (VAS) score, and performing satisfaction survey. At the 1st week and 2nd week after surgery, the clinical rehabilitation effect in the intervention group was better regarding lower limb action ability, lower limb DVT, muscle strength of quadriceps, VAS score, and patient satisfaction, as compared with the control group. However, there was no significant difference at the 1st month and the 3rd month after surgery when comparing the intervention group to the control group. In the early postoperative stage, lower limb rehabilitation gymnastics can effectively improve the recovery of lower limb function, beneficial to reducing postoperative complications such as lower limb DVT and muscle atrophy, and increasing patient satisfaction rate. PMID:27537579

The effect of lower limb rehabilitation gymnastics on postoperative rehabilitation in elderly patients with femoral shaft fracture: A retrospective case-control study.

PubMed

Yang, Si-Dong; Ning, Sheng-Hua; Zhang, Li-Hong; Zhang, Ying-Ze; Ding, Wen-Yuan; Yang, Da-Long

2016-08-01

The purpose of this study was to explore the effect of lower limb rehabilitation gymnastics on postoperative rehabilitation in elderly patients with femoral shaft fracture after undergoing intramedullary nail fixation surgery.We collected medical records of elderly patients aged ≥ 60 years with femoral shaft fracture between 03/2010 and 03/2015 in Longyao County Hospital. Totally, 160 patients were identified and divided into the intervention group (n = 80) and the control group (n = 80). During the postoperative period, the intervention group received lower limb rehabilitation gymnastics treatment for 3 months, but the control group did not. All patients were routinely asked to return hospital for a check in the 1st postoperative week, as well as the 2nd week, the 1st month, and the 3rd month, after surgery. The clinical rehabilitation effect was evaluated by checking lower limb action ability, detecting the lower limb deep venous thrombosis (DVT), scoring muscle strength of quadriceps and visual analog scale (VAS) score, and performing satisfaction survey.At the 1st week and 2nd week after surgery, the clinical rehabilitation effect in the intervention group was better regarding lower limb action ability, lower limb DVT, muscle strength of quadriceps, VAS score, and patient satisfaction, as compared with the control group. However, there was no significant difference at the 1st month and the 3rd month after surgery when comparing the intervention group to the control group.In the early postoperative stage, lower limb rehabilitation gymnastics can effectively improve the recovery of lower limb function, beneficial to reducing postoperative complications such as lower limb DVT and muscle atrophy, and increasing patient satisfaction rate.

Skin blood flow: a comparison of transcutaneous oximetry and laser Doppler flowmetry.

PubMed

Allen, P I; Goldman, M

1987-10-01

In normal limbs skin blood flow (SBF) falls on standing, but in ischaemic limbs there is a characteristic blush on dependancy. We studied the effect of changing posture in a range of ischaemic limbs, using two non-invasive techniques--laser Doppler (LD) and transcutaneous oximetry (TcPO2). Warmed TcPO2 and LD probes were placed over the first metatarsal cleft and SBF recorded with the limb horizontal, dependant and elevated. Ankle to brachial pressure ratios (A:B) were also measured. Twelve patients with lower limb ischaemia, mean A:B ratio 0.5 +/- 0.21 (+/- S.D.) were compared with 21 asymptomatic controls, mean A:B ratio 1.2 +/- 0.15. In the controls, neither TcPO2 nor LD values changed significantly with limb position. Both flux and oxygen tension were significantly lower in ischaemic limbs in all positions; on lowering the ischaemic limb, flux unexpectedly rose to 23.5 +/- 17.7 V from a mean of 14 + 9.0 V (horizontal). Both TcPO2 and LD correlated well with A:B ratio in two positions: horizontal r (TcPO2) = 0.73, r(LD) = 0.57; elevated r(TcPO2) = 0.78, r(LD) = 0.68. Overall there was a highly significant correlation between LD and TcPO2 (r = 0.6, P less than 0.001, Student's test), but this was strongest in the elevated position (r = 0.87, P less than 0.001). LD and TcPO2 relate to A:B ratio and to each other, particularly in the stressed limb; in the well perfused limb, the poorer correlation suggests skin perfusion is not linearly related to tissue oxygen tension.

Update and validation of the Society for Vascular Surgery wound, ischemia, and foot infection threatened limb classification system.

PubMed

Mills, Joseph L

2014-03-01

The diagnosis of critical limb ischemia, first defined in 1982, was intended to delineate a patient cohort with a threatened limb and at risk for amputation due to severe peripheral arterial disease. The influence of diabetes and its associated neuropathy on the pathogenesis-threatened limb was an excluded comorbidity, despite its known contribution to amputation risk. The Fontaine and Rutherford classifications of limb ischemia severity have also been used to predict amputation risk and the likelihood of tissue healing. The dramatic increase in the prevalence of diabetes mellitus and the expanding techniques of arterial revascularization has prompted modification of peripheral arterial disease classification schemes to improve outcomes analysis for patients with threatened limbs. The diabetic patient with foot ulceration and infection is at risk for limb loss, with abnormal arterial perfusion as only one determinant of outcome. The wound extent and severity of infection also impact the likelihood of limb loss. To better predict amputation risk, the Society for Vascular Surgery Lower Extremity Guidelines Committee developed a classification of the threatened lower extremity that reflects these important clinical considerations. Risk stratification is based on three major factors that impact amputation risk and clinical management: wound, ischemia, and foot infection. This classification scheme is relevant to the patient with critical limb ischemia because many are also diabetic. Implementation of the wound, ischemia, and foot infection classification system in critical limb ischemia patients is recommended and should assist the clinician in more meaningful analysis of outcomes for various forms of wound and arterial revascularizations procedures required in this challenging, patient population. Copyright © 2014 Elsevier Inc. All rights reserved.

Can Video Self-Modeling Improve Affected Limb Reach and Grasp Ability in Stroke Patients?

PubMed

Steel, Kylie Ann; Mudie, Kurt; Sandoval, Remi; Anderson, David; Dogramaci, Sera; Rehmanjan, Mohammad; Birznieks, Ingvars

2018-01-01

The authors examined whether feedforward video self-modeling (FF VSM) would improve control over the affected limb, movement self-confidence, movement self-consciousness, and well-being in 18 stroke survivors. Participants completed a cup transport task and 2 questionnaires related to psychological processes pre- and postintervention. Pretest video footage of the unaffected limb performing the task was edited to create a best-of or mirror-reversed training DVD, creating the illusion that patients were performing proficiently with the affected limb. The training yielded significant improvements for the forward movement of the affected limb compared to the unaffected limb. Significant improvements were also seen in movement self-confidence, movement self-consciousness, and well-being. FF VSM appears to be a viable way to improve motor ability in populations with movement disorders.

Functional analysis of limb enhancers in the developing fin

PubMed Central

Booker, Betty M.; Murphy, Karl K.

2013-01-01

Despite diverging ~365 million years ago, tetrapod limbs and pectoral fins express similar genes that could be regulated by shared regulatory elements. In this study, we set out to analyze the ability of enhancers to maintain tissue specificity in these two divergent structures. We tested 22 human sequences that were previously reported as mouse limb enhancers for their enhancer activity in zebrafish (Danio rerio). Using a zebrafish enhancer assay, we found that 10/22 (45 %) were positive for pectoral fin activity. Analysis of the various criteria that correlated with positive fin activity found that both spatial limb activity and evolutionary conservation are not good predictors of fin enhancer activity. These results suggest that zebrafish enhancer assays may be limited in detecting human limb enhancers, and this limitation does not improve by the use of limb spatial expression or evolutionary conservation. PMID:24068387

Morphogenesis and evolution of vertebrate appendicular muscle

PubMed Central

HAINES, LYNN; CURRIE, PETER D.

2001-01-01

Two different modes are utilised by vertebrate species to generate the appendicular muscle present within fins and limbs. Primitive Chondricthyan or cartilaginous fishes use a primitive mode of muscle formation to generate the muscle of the fins. Direct epithelial myotomal extensions invade the fin and generate the fin muscles while remaining in contact with the myotome. Embryos of amniotes such as chick and mouse use a similar mechanism to that deployed in the bony teleost species, zebrafish. Migratory mesenchymal myoblasts delaminate from fin/limb level somites, migrate to the fin/limb field and differentiate entirely within the context of the fin/limb bud. Migratory fin and limb myoblasts express identical genes suggesting that they possess both morphogenetic and molecular identity. We conclude that the mechanisms controlling tetrapod limb muscle formation arose prior to the Sarcopterygian or tetrapod radiation. PMID:11523824

Slow Movements of Bio-Inspired Limbs

NASA Astrophysics Data System (ADS)

Babikian, Sarine; Valero-Cuevas, Francisco J.; Kanso, Eva

2016-10-01

Slow and accurate finger and limb movements are essential to daily activities, but the underlying mechanics is relatively unexplored. Here, we develop a mathematical framework to examine slow movements of tendon-driven limbs that are produced by modulating the tendons' stiffness parameters. Slow limb movements are driftless in the sense that movement stops when actuations stop. We demonstrate, in the context of a planar tendon-driven system representing a finger, that the control of stiffness suffices to produce stable and accurate limb postures and quasi-static (slow) transitions among them. We prove, however, that stable postures are achievable only when tendons are pretensioned, i.e., they cannot become slack. Our results further indicate that a non-smoothness in slow movements arises because the precision with which individual stiffnesses need to be altered changes substantially throughout the limb's motion.

Progress Toward Optimizing Prosthetic Socket Fit and Suspension Using Elevated Vacuum to Promote Residual Limb Health

PubMed Central

Wernke, Matthew M.; Schroeder, Ryan M.; Haynes, Michael L.; Nolt, Lonnie L.; Albury, Alexander W.; Colvin, James M.

2017-01-01

Objective: Prosthetic sockets are custom made for each amputee, yet there are no quantitative tools to determine the appropriateness of socket fit. Ensuring a proper socket fit can have significant effects on the health of residual limb soft tissues and overall function and acceptance of the prosthetic limb. Previous work found that elevated vacuum pressure data can detect movement between the residual limb and the prosthetic socket; however, the correlation between the two was specific to each user. The overall objective of this work is to determine the relationship between elevated vacuum pressure deviations and prosthetic socket fit. Approach: A tension compression machine was used to apply repeated controlled forces onto a residual limb model with sockets of different internal volume. Results: The vacuum pressure–displacement relationship was dependent on socket fit. The vacuum pressure data were sensitive enough to detect differences of 1.5% global volume and can likely detect differences even smaller. Limb motion was reduced as surface area of contact between the limb model and socket was maximized. Innovation: The results suggest that elevated vacuum pressure data provide information to quantify socket fit. Conclusions: This study provides evidence that the use of elevated vacuum pressure data may provide a method for prosthetists to quantify and monitor socket fit. Future studies should investigate the relationship between socket fit, limb motion, and limb health to define optimal socket fit parameters. PMID:28736683

Computer-assisted kinematic evaluation of induced compensatory movements resembling lameness in horses trotting on a treadmill.

PubMed

Kelmer, Gal; Keegan, Kevin G; Kramer, Joanne; Wilson, David A; Pai, Frank P; Singh, Prableen

2005-04-01

To characterize compensatory movements of the head and pelvis that resemble lameness in horses. 17 adult horses. Kinematic evaluations were performed while horses trotted on a treadmill before and after shoe-induced lameness. Lameness was quantified and the affected limb determined by algorithms that measured asymmetry in vertical movement of the head and pelvis. Induced primary lameness and compensatory movements resembling lameness were assessed by the Friedman test. Association between induced lameness and compensatory movements was examined by regression analysis. Compensatory movements resembling lameness in the ipsilateral forelimb were seen with induced lameness of a hind limb. There was less downward and less upward head movement during and after the stance phase of the ipsilateral forelimb. Doubling the severity of lameness in the hind limb increased severity of the compensatory movements in the ipsilateral forelimb by 50%. Compensatory movements resembling lameness of the hind limb were seen after induced lameness in a forelimb. There was less upward movement of the pelvis after the stance phase of the contralateral hind limb and, to a lesser extent, less downward movement of the pelvis during the stance phase of the ipsilateral hind limb. Doubling the severity of lameness in the forelimb increased compensatory movements of the contralateral hind limb by 5%. Induced lameness in a hind limb causes prominent compensatory movements resembling lameness in the ipsilateral forelimb. Induced lameness in a forelimb causes slight compensatory movements resembling lameness in the ipsilateral and contralateral hind limbs.

Comparative architectural properties of limb muscles in Crocodylidae and Alligatoridae and their relevance to divergent use of asymmetrical gaits in extant Crocodylia.

PubMed

Allen, Vivian; Molnar, Julia; Parker, William; Pollard, Andrea; Nolan, Grant; Hutchinson, John R

2014-12-01

Crocodiles and their kin (Crocodylidae) use asymmetrical (bounding and galloping) gaits when moving rapidly. Despite being morphologically and ecologically similar, it seems alligators and their kin (Alligatoridae) do not. To investigate a possible anatomical basis for this apparent major difference in locomotor capabilities, we measured relative masses and internal architecture (fascicle lengths and physiological cross-sectional areas) of muscles of the pectoral and pelvic limbs of 40 individuals from six representative species of Crocodylidae and Alligatoridae. We found that, relative to body mass, Crocodylidae have significantly longer muscle fascicles (increased working range), particularly in the pectoral limb, and generally smaller muscle physiological cross-sectional areas (decreased force-exerting capability) than Alligatoridae. We therefore hypothesise that the ability of some crocodylians to use asymmetrical gaits may be limited more by the ability to make large, rapid limb motions (especially in the pectoral limb) than the ability to exert large limb forces. Furthermore, analysis of scaling patterns in muscle properties shows that limb anatomy in the two clades becomes more divergent during ontogeny. Limb muscle masses, fascicle lengths and physiological cross-sectional areas scale with significantly larger coefficients in Crocodylidae than Alligatoridae. This combination of factors suggests that inter-clade disparity in maximal limb power is highest in adult animals. Therefore, despite their apparent morphological similarities, both mean values and scaling patterns suggest that considerable diversity exists in the locomotor apparatus of extant Crocodylia. © 2014 Anatomical Society.

Prior nonhip limb fracture predicts subsequent hip fracture in institutionalized elderly people.

PubMed

Nakamura, K; Takahashi, S; Oyama, M; Oshiki, R; Kobayashi, R; Saito, T; Yoshizawa, Y; Tsuchiya, Y

2010-08-01

This 1-year cohort study of nursing home residents revealed that historical fractures of upper limbs or nonhip lower limbs were associated with hip fracture (hazard ratio = 2.14), independent of activities of daily living (ADL), mobility, dementia, weight, and type of nursing home. Prior nonhip fractures are useful for predicting of hip fracture in institutional settings. The aim of this study was to evaluate the utility of fracture history for the prediction of hip fracture in nursing home residents. This was a cohort study with a 1-year follow-up. Subjects were 8,905 residents of nursing homes in Niigata, Japan (mean age, 84.3 years). Fracture histories were obtained from nursing home medical records. ADL levels were assessed by caregivers. Hip fracture diagnosis was based on hospital medical records. Subjects had fracture histories of upper limbs (5.0%), hip (14.0%), and nonhip lower limbs (4.6%). Among historical single fractures, only prior nonhip lower limbs significantly predicted subsequent fracture (adjusted hazard ratio, 2.43; 95% confidence interval (CI), 1.30-4.57). The stepwise method selected the best model, in which a combined historical fracture at upper limbs or nonhip lower limbs (adjusted hazard ratio, 2.14; 95% CI, 1.30-3.52), dependence, ADL levels, mobility, dementia, weight, and type of nursing home independently predicted subsequent hip fracture. A fracture history at upper or nonhip lower limbs, in combination with other known risk factors, is useful for the prediction of future hip fracture in institutional settings.

Peripheral neuropathy reduces asymmetries in inter-limb transfer in a visuo-motor task.

PubMed

Pan, Zhujun; Van Gemmert, Arend W A

2016-01-01

Asymmetry of inter-limb transfer has been associated with the specialization of the dominant and non-dominant motor system. Reductions of asymmetry have been interpreted as behavioural evidence showing a decline of hemispheric lateralization. A previous study showed that ageing did not qualitatively change the inter-limb transfer asymmetry of a visuo-motor task. The current study elaborates on these findings; it examines whether diminished somatosensory information as a result of peripheral neuropathy (PN) adversely affects inter-limb transfer asymmetry. Twenty individuals affected by PN and 20 older controls were recruited and divided equally across two groups. One group trained a visuo-motor task with the right hand while the other group trained it with the left hand. Performance (initial direction error) of the untrained hand before and after training was collected to determine learning effects from inter-limb transfer. Similar to previous studies, the current study showed asymmetric inter-limb transfer in older controls. In contrast, PN showed inter-limb transfer in both directions indicating that PN reduces inter-limb transfer asymmetry. Increased bilateral hemispheric recruitment is suggested to be responsible for this reduced asymmetry which may compensate for deteriorated tactile and/or proprioceptive inputs in PN. Two possible hypotheses are discussed explaining the relationship between declined somatosensory information and increases in bilateral hemispheric recruitment.

Neurotrophic regulation of epidermal dedifferentiation during wound healing and limb regeneration in the axolotl (Ambystoma mexicanum).

PubMed

Satoh, A; Graham, G M C; Bryant, S V; Gardiner, D M

2008-07-15

Adult urodeles (salamanders) are unique in their ability to regenerate complex organs perfectly. The recently developed Accessory Limb Model (ALM) in the axolotl provides an opportunity to identify and characterize the essential signaling events that control the early steps in limb regeneration. The ALM demonstrates that limb regeneration progresses in a stepwise fashion that is dependent on signals from the wound epidermis, nerves and dermal fibroblasts from opposite sides of the limb. When all the signals are present, a limb is formed de novo. The ALM thus provides an opportunity to identify and characterize the signaling pathways that control blastema morphogenesis and limb regeneration. In the present study, we have utilized the ALM to identity the buttonhead-like zinc-finger transcription factor, Sp9, as being involved in the formation of the regeneration epithelium. Sp9 expression is induced in basal keratinocytes of the apical blastema epithelium in a pattern that is comparable to its expression in developing limb buds, and it thus is an important marker for dedifferentiation of the epidermis. Induction of Sp9 expression is nerve-dependent, and we have identified KGF as an endogenous nerve factor that induces expression of Sp9 in the regeneration epithelium.

Three-dimensional contrast-enhanced magnetic resonance angiography for anterolateral thigh flap outlining: A retrospective case series of 68 patients.

PubMed

Jiang, Chunjing; Lin, Ping; Fu, Xiaoyan; Shu, Jiner; Li, Huimin; Hu, Xiaogang; He, Jianrong; Ding, Mingxing

2016-08-01

Flap transfer is increasingly used for repairing limb defects secondary to trauma or tumor, and appropriate preoperative planning plays a critical role. The present study aimed to examine the use of three-dimensional (3D) contrast-enhanced magnetic resonance angiography (CE-MRA) in evaluating the blood supply distribution and perforating branch pattern of anterolateral thigh (ALT) flaps. Bilateral donor lower limbs were scanned in 68 patients (136 limbs) using a Siemens Avanto 1.5 T magnetic resonance imaging scanner with a 3D fast low-angle shot sequence, following the thin-slab maximum intensity projection (TS-MIP) technique. The lateral femoral circumflex artery (LFCA) was visualized in all patients: 101 limbs (101/136, 74.3%) were type I; 20 limbs (20/136, 14.7%) were type II; 3 limbs (3/136, 2.2%) were type III; and 12 limbs (12/136, 8.8%) were type IV. Tertiary branches were identified in 94 limbs (94/136, 69.1%). Donor flaps were outlined according to MRA TS-MIP findings in 4 patients. All flaps survived uneventfully following the transfer. In donor flap outlining, 3D CE-MRA with the TS-MIP technique allowed an accurate, direct visualization of the branching pattern and distribution profile of the LFCA supplying the ALT flap.

Studies of limb-dislodging forces acting on an ejection seat occupant.

PubMed

Schneck, D J

1980-03-01

A mathematical theory is being developed in order to calculate the aerodynamic loading to which a pilot is exposed during high-speed ejections. Neglecting the initial effects of flow separation, results thus far indicate that a pilot's musculoskeletal system is not likely to withstand the tendency for limb-flailing if he is ejecting at Mach numbers in excess of about 0.7. This tendency depends very strongly upon the angle at which the pilot's limbs intercept a high-speed flow; the forces that cause limb dislodgement increase dramatically with speed of ejection. Examining the time-course of limb-dislodging forces after the initial onset of windblast, the theory further predicts the generation of a double vortex street pattern on the downstream side of the limbs of an ejection seat occupant. This results in the corresponding appearance of oscillating forces tending to cause lateral motion (vibration) of the limbs. The amplitude and frequency of these oscillating forces are also very dependent on the Mach number of ejection and the angle at which the pilot's limbs intercept the flow. However, even at moderate Mach numbers, the frequency can be as high as 100 cycles per second, and the amplitude rapidly exceeds a pilot's musculo-skeletal resistive powers for Mach numbers above 0.7.

Six-degree-of-freedom parallel minimanipulator with three inextensible limbs

NASA Technical Reports Server (NTRS)

Tahmasebi, Farhad (Inventor); Tsai, Lung-Wen (Inventor)

1994-01-01

A Six-Degree-of-Freedom Parallel-Manipulator having three inextensible limbs for manipulating a platform is described. The three inextensible limbs are attached via universal joints to the platform at non-collinear points. Each of the inextensible limbs is also attached via universal joints to a two-degree-of-freedom parallel driver such as a five-bar linkage, a pantograph, or a bidirectional linear stepper motor. The drivers move the lower ends of the limbs parallel to a fixed base and thereby provide manipulation of the platform. The actuators are mounted on the fixed base without using any power transmission devices such as gears or belts.

Facts about Upper and Lower Limb Reduction Defects

MedlinePlus

... its normal size or is missing. What We Know About Upper and Lower Limb Reduction Defects How ... and productive lives. What We Still Do Not Know About Upper and Lower Limb Reduction Defects What ...

Clouds above the Martin Limb: Viking observations

NASA Technical Reports Server (NTRS)

Martin, L. J.; Baum, W. A.; Wasserman, L. H.; Kreidl, T. J.

1984-01-01

Whenever Viking Orbiter images included the limb of Mars, they recorded one or more layers of clouds above the limb. The height above the limb and the brightness (reflectivity) of these clouds were determined in a selected group of these images. Normalized individual brightness profiles of three separate traverses across the limb of each image are shown. The most notable finding is that some of these clouds can be very high. Many reach heights of over 60 km, and several are over 70 km above the limb. Statistically, the reflectivity of the clouds increases with phase angle. Reflectivity and height both appear to vary with season, but the selected images spanned only one Martian year, so the role of seasons cannot be isolated. Limb clouds in red-filter images tend to be brighter than violet-filter images, but both season and phase appear to be more dominant factors. Due to the limited sample available, the possible influences of latitude and longitude are less clear. The layering of these clouds ranges from a single layer to five or more layers. Reflectivity gradients range from smooth and gentle to steep and irregular.

Functional testing of space flight induced changes in tonic motor control by using limb-attached excitation and load devices

NASA Astrophysics Data System (ADS)

Gallasch, Eugen; Kozlovskaya, Inessa

2007-02-01

Long term space flights induce atrophy and contractile changes on postural muscles such effecting tonic motor control. Functional testing of tonic motor control structures is a challenge because of the difficulties to deliver appropriate test forces on crew members. In this paper we propose two approaches for functional testing by using limb attached loading devices. The first approach is based on a frequency and amplitude controllable moving magnet exciter to deliver sinusoidal test forces during limb postures. The responding limb deflection is recorded by an embedded accelerometer to obtain limb impedance. The second approach is based on elastic limb loading to evoke self-excited oscillations during arm extensions. Here the contraction force at the oscillation onset provides information about limb stiffness. The rationale for both testing approaches is based on Feldman's λ-model. An arm expander based on the second approach was probed in a 6-month MIR space flight. The results obtained from the load oscillations, confirmed that this device is well suited to capture space flight induced neuromuscular changes.

Driving ability following upper limb amputation.

PubMed

Burger, Helena; Marincek, Crt

2013-10-01

In the existing literature, there is scarce information about subjects with upper limb amputation and driving. The aim of this study was to find out how frequently subjects following upper limb amputation have problems when driving; most frequently proposed adaptations and, when possible, factors that influence driving ability. Retrospective clinical study. Medical records were reviewed of all subjects following upper limb amputation who had been amputated in the last 5 years and those with congenital upper limb deficiency who in the last 5 years turned 17. Out of 37 subjects, 7 did not attend the clinic for assessment of driving abilities. They were significantly older at the time of the amputation (p < 0.001). To the remaining 30 who attended driving assessment, zero to four car adaptations (two on average) were proposed. There were no correlations between the number of suggested car adaptations and the age at the time of the amputation, amputation level, education and severity of phantom limb pain. Type of prosthesis also did not influence the number of car adaptations. Most people following upper limb amputation need at least one car adaptation for safe driving.

Proximal—distal pattern formation in Drosophila: cell autonomous requirement for Distal-less gene activity in limb development

PubMed Central

Cohen, Stephen M.; Jürgens, Gerd

1989-01-01

Limb development in the Drosophila embryo requires a pattern-forming system to organize positional information along the proximal–distal axis of the limb. This system must function in the context of the well characterized anterior–posterior and dorsal–ventral pattern-forming systems that are required to organize the body plan of the embryo. By genetic criteria the Distal-less gene appears to play a central role in limb development. Lack-of-function Distal-less mutations cause the deletion of a specific subset of embryonic peripheral sense organs that represent the evolutionary remnants of larval limbs. Distal-less activity is also required in the imaginal discs for the development of adult limbs. This requirement is cell autonomous and region specific within the developing limb primordium. Production of genetically mosaic imaginal discs, in which clones of cells lack Distal-less activity, indicates the existence of an organized proximal–distal positional information in very young imaginal disc primordia. We suggest that this graded positional information may depend on the activity of the Distal-less gene. Images PMID:16453891

SPECTRO-POLARIMETRIC SIMULATIONS OF THE SOLAR LIMB: ABSORPTION-EMISSION Fe I 6301.5 Å AND 6302.5 Å LINE PROFILES AND TORSIONAL FLOWS IN THE INTERGRANULAR MAGNETIC FLUX CONCENTRATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shelyag, S.

2015-03-01

Using radiative magnetohydrodynamic simulations of the magnetized solar photosphere and detailed spectro-polarimetric diagnostics with the Fe I 6301.5 Å and 6302.5 Å photospheric lines in the local thermodynamic equilibrium approximation, we model active solar granulation as if it was observed at the solar limb. We analyze general properties of the radiation across the solar limb, such as the continuum and the line core limb darkening and the granulation contrast. We demonstrate the presence of profiles with both emission and absorption features at the simulated solar limb, and pure emission profiles above the limb. These profiles are associated with the regionsmore » of strong linear polarization of the emergent radiation, indicating the influence of the intergranular magnetic fields on the line formation. We analyze physical origins of the emission wings in the Stokes profiles at the limb, and demonstrate that these features are produced by localized heating and torsional motions in the intergranular magnetic flux concentrations.« less

Assisting people with attention deficit hyperactivity disorder by actively reducing limb hyperactive behavior with a gyration air mouse through a controlled environmental stimulation.

PubMed

Shih, Ching-Hsiang

2011-01-01

The latest researches have adopted software technology turning the gyration air mouse into a high performance limb movement detector, and have assessed whether two persons with multiple disabilities would be able to control an environmental stimulation using limb movement. This study extends gyration air mouse functionality by actively reducing limb hyperactive behavior to assess whether two persons with attention deficit hyperactivity disorder (ADHD) would be able to actively reduce their limb hyperactive behavior by controlling their favorite stimulation on/off using a gyration air mouse with a newly developed actively limb hyperactive behavior reducing program (ALHBRP). The study was performed according to an ABAB design, in which A represented the baseline and B represented intervention phases. Data showed that both participants significantly increased their time duration of maintaining a static limb posture (TDMSLP) to activate the control system in order to produce environmental stimulation during the intervention phases. Practical and developmental implications of the findings are discussed. Copyright © 2010 Elsevier Ltd. All rights reserved.

A New Animal Model for Developing a Somatosensory Neural Interface for Prosthetic Limbs

DTIC Science & Technology

2008-02-12

interface for neuroprosthetic limbs . PI: Douglas J. Weber, Ph.D. University of Pittsburgh 1 10/15/2007 Scientific progress and accomplishments. We...information to the brain. A new animal model for developing a somatosensory neural interface for neuroprosthetic limbs . PI: Douglas J. Weber, Ph.D...A new animal model for developing a somatosensory neural interface for neuroprosthetic limbs . PI: Douglas J. Weber, Ph.D. University of Pittsburgh

Influence of Total Knee Arthroplasty on Gait Mechanics of the Replaced and Non-Replaced Limb During Stair Negotiation.

PubMed

Standifird, Tyler W; Saxton, Arnold M; Coe, Dawn P; Cates, Harold E; Reinbolt, Jeffrey A; Zhang, Songning

2016-01-01

This study compared biomechanics during stair ascent in replaced and non-replaced limbs of total knee arthroplasty (TKA) patients with control limbs of healthy participants. Thirteen TKA patients and fifteen controls performed stair ascent. Replaced and non-replaced knees of TKA patients were less flexed at contact compared to controls. The loading response peak knee extension moment was greater in control and non-replaced knees compared with replaced. The push-off peak knee abduction moment was elevated in replaced limbs compared to controls. Loading and push-off peak hip abduction moments were greater in replaced limbs compared to controls. The push-off peak hip abduction moment was greater in non-replaced limbs compared to controls. Future rehabilitation protocols should consider the replaced knee and also the non-replaced knee and surrounding joints. Copyright © 2016 Elsevier Inc. All rights reserved.

Symmetrical upper limb peromelia and lower limb phocomelia associated with a de novo apparently balanced reciprocal translocation: 46,XX,t(2; 12)(p25.1;q24.1).

PubMed

Murray, R S; Keeling, J W; Ellis, P M; FitzPatrick, D R

2002-04-01

We report a female fetus of 20 weeks gestation with severe symmetrical deformity affecting all four limbs. These deformities were unusual in that there was upper limb peromelia and lower limb phocomelia. No additional major malformations were identified on postmortem examination. In particular there was no evidence of splenogonadal fusion or micrognathia and hypoglossia. The limb malformations in this case are associated with a de novo apparently balanced reciprocal translocation 46,XX,t(2;12)(p25.1;q24.1). The cytogenetic features of Roberts-SC phocomelia syndrome were not detected. Unfortunately, the fibroblast line died and no FISH or DNA analysis could be carried out. In spite of this, the case is presented as it may be useful to other researchers in the selection of candidate genes for mendelian forms of peromelia and phocomelia.

Mutations in WNT7A cause a range of limb malformations, including Fuhrmann syndrome and Al-Awadi/Raas-Rothschild/Schinzel phocomelia syndrome.

PubMed

Woods, C G; Stricker, S; Seemann, P; Stern, R; Cox, J; Sherridan, E; Roberts, E; Springell, K; Scott, S; Karbani, G; Sharif, S M; Toomes, C; Bond, J; Kumar, D; Al-Gazali, L; Mundlos, S

2006-08-01

Fuhrmann syndrome and the Al-Awadi/Raas-Rothschild/Schinzel phocomelia syndrome are considered to be distinct limb-malformation disorders characterized by various degrees of limb aplasia/hypoplasia and joint dysplasia in humans. In families with these syndromes, we found homozygous missense mutations in the dorsoventral-patterning gene WNT7A and confirmed their functional significance in retroviral-mediated transfection of chicken mesenchyme cell cultures and developing limbs. The results suggest that a partial loss of WNT7A function causes Fuhrmann syndrome (and a phenotype similar to mouse Wnt7a knockout), whereas the more-severe limb truncation phenotypes observed in Al-Awadi/Raas-Rothschild/Schinzel phocomelia syndrome result from null mutations (and cause a phenotype similar to mouse Shh knockout). These findings illustrate the specific and conserved importance of WNT7A in multiple aspects of vertebrate limb development.

Mutations in WNT7A Cause a Range of Limb Malformations, Including Fuhrmann Syndrome and Al-Awadi/Raas-Rothschild/Schinzel Phocomelia Syndrome

PubMed Central

Woods, C. G.; Stricker, S.; Seemann, P.; Stern, R.; Cox, J.; Sherridan, E.; Roberts, E.; Springell, K.; Scott, S.; Karbani, G.; Sharif, S. M.; Toomes, C.; Bond, J.; Kumar, D.; Al-Gazali, L.; Mundlos, S.

2006-01-01

Fuhrmann syndrome and the Al-Awadi/Raas-Rothschild/Schinzel phocomelia syndrome are considered to be distinct limb-malformation disorders characterized by various degrees of limb aplasia/hypoplasia and joint dysplasia in humans. In families with these syndromes, we found homozygous missense mutations in the dorsoventral-patterning gene WNT7A and confirmed their functional significance in retroviral-mediated transfection of chicken mesenchyme cell cultures and developing limbs. The results suggest that a partial loss of WNT7A function causes Fuhrmann syndrome (and a phenotype similar to mouse Wnt7a knockout), whereas the more-severe limb truncation phenotypes observed in Al-Awadi/Raas-Rothschild/Schinzel phocomelia syndrome result from null mutations (and cause a phenotype similar to mouse Shh knockout). These findings illustrate the specific and conserved importance of WNT7A in multiple aspects of vertebrate limb development. PMID:16826533

[Implementation of control system and software design for limbs rehabilitation training based on PCI-1240].

PubMed

Zhu, Wenchao; Xu, Xiulin; Hu, Xiufang; An, Meijun

2017-06-01

This article presents the design of a motion control system for seated lower-limb rehabilitation training. The system is composed of lower limb exoskeleton, motor drive circuit, program of motion control, and so forth. The power of lower limbs joints is provided by six motors. The PCI-1240 motion control card is used as the core. This study achieved repetitive rotation training and gait trajectory training of lower limbs joints, of which the velocity, angle and time can be accurately controlled and adjusted. The experimental results showed that the motion control system can meet the requirement of repetitive rehabilitation training for patients with lower limb dysfunction. This article provides a new method to the research of motion control system in rehabilitation training, which can promote industrial automation technique to be used for health care, and conducive to the further study of the rehabilitation robot.

Upper extremity prosthesis user perspectives on unmet needs and innovative technology.

PubMed

Benz, Heather L; Jia Yao; Rose, Laura; Olgac, Okan; Kreutz, Karen; Saha, Anindita; Civillico, Eugene F

2016-08-01

The needs of individuals with upper limb amputation and congenital limb difference are not being fully met by current prostheses, as evidenced by prosthesis rejection, non-wear, and user reports of pain and challenging activities. Emerging technologies such as dexterous sensorized robotic limbs, osseointegrated prostheses, implantable EMG electrodes, and electrical stimulation for sensory feedback have the potential to address unmet needs, but pose additional risks. We plan to assess upper limb prosthesis user needs and perspectives on these new benefits and risks using an extensive quantitative survey. In preparation for this survey, we report here on qualitative interviews with seven individuals with upper limb amputation or congenital limb difference. Unstructured text was mined using topic modeling and the results compared with identified themes. A more complete understanding of how novel technologies could address real user concerns will inform implementation of new technologies and regulatory decision-making.

Upper Extremity Prosthesis User Perspectives on Unmet Needs and Innovative Technology

PubMed Central

Benz, Heather L.; Yao, Jia; Rose, Laura; Olgac, Okan; Kreutz, Karen; Saha, Anindita; Civillico, Eugene F.

2017-01-01

The needs of individuals with upper limb amputation and congenital limb difference are not being fully met by current prostheses, as evidenced by prosthesis rejection, non-wear, and user reports of pain and challenging activities. Emerging technologies such as dexterous sensorized robotic limbs, osseointegrated prostheses, implantable EMG electrodes, and electrical stimulation for sensory feedback have the potential to address unmet needs, but pose additional risks. We plan to assess upper limb prosthesis user needs and perspectives on these new benefits and risks using an extensive quantitative survey. In preparation for this survey, we report here on qualitative interviews with seven individuals with upper limb amputation or congenital limb difference. Unstructured text was mined using topic modeling and the results compared with identified themes. A more complete understanding of how novel technologies could address real user concerns will inform implementation of new technologies and regulatory decision-making. PMID:28268333

Environmental monitoring for the DOE coolside and LIMB demonstration extension projects

DOE Office of Scientific and Technical Information (OSTI.GOV)

White, T.; Contos, L.; Adams, L.

1992-03-01

The purpose of this document is to present environmental monitoring data collected during the US Department of Energy Limestone Injection Multistage Burner (DOE LIMB) Demonstration Project Extension at the Ohio Edison Edgewater Generating Station in Lorain, Ohio. The DOE project is an extension of the US Environmental Protection Agency's (EPA's) original LIMB Demonstration. The program is operated nuclear DOE's Clean Coal Technology Program of emerging clean coal technologies'' under the categories of in boiler control of oxides of sulfur and nitrogen'' as well as post-combustion clean-up.'' The objective of the LIMB program is to demonstrate the sulfur dioxide (SO{sub 2})more » and nitrogen oxide (NO{sub x}) emission reduction capabilities of the LIMB system. The LIMB system is a retrofit technology to be used for existing coal-fired boilers equipped with electrostatic precipitators (ESPs).« less

Environmental monitoring for the DOE coolside and LIMB demonstration extension projects. Final report, May--August 1991

DOE Office of Scientific and Technical Information (OSTI.GOV)

White, T.; Contos, L.; Adams, L.

1992-03-01

The purpose of this document is to present environmental monitoring data collected during the US Department of Energy Limestone Injection Multistage Burner (DOE LIMB) Demonstration Project Extension at the Ohio Edison Edgewater Generating Station in Lorain, Ohio. The DOE project is an extension of the US Environmental Protection Agency`s (EPA`s) original LIMB Demonstration. The program is operated nuclear DOE`s Clean Coal Technology Program of ``emerging clean coal technologies`` under the categories of ``in boiler control of oxides of sulfur and nitrogen`` as well as ``post-combustion clean-up.`` The objective of the LIMB program is to demonstrate the sulfur dioxide (SO{sub 2})more » and nitrogen oxide (NO{sub x}) emission reduction capabilities of the LIMB system. The LIMB system is a retrofit technology to be used for existing coal-fired boilers equipped with electrostatic precipitators (ESPs).« less

Glucose uptake and glycogen synthesis in muscles from immobilized limbs

NASA Technical Reports Server (NTRS)

Nicholson, W. F.; Watson, P. A.; Booth, F. W.

1984-01-01

Defects in glucose metabolism in muscles of immobilized limbs of mice were related to alterations in insulin binding, insulin responsiveness, glucose supply, and insulin activation of glycogen synthase. These were tested by in vitro methodology. A significant lessening in the insulin-induced maximal response of 2-deoxyglucose uptake into the mouse soleus muscle occurred between the 3rd and 8th h of limb immobilization, suggesting a decreased insulin responsiveness. Lack of change in the specific binding of insulin to muscles of 24-h immobilized limbs indicates that a change in insulin receptor number did not play a role in the failure of insulin to stimulate glucose metabolism. Its inability to stimulate glycogen synthesis in muscle from immobilized limbs is due, in part, to a lack of glucose supply to glycogen synthesis and also to the ineffectiveness of insulin to increase the percentage of glycogen synthase in its active form in muscles from 24-h immobilized limbs.

Determinants of midterm functional outcomes, wound healing, and resources used in a hospital-based limb preservation program.

PubMed

Ramanan, Bala; Ahmed, Ayman; Wu, Bian; Causey, Marlin W; Gasper, Warren J; Vartanian, Shant M; Reyzelman, Alexander M; Hiramoto, Jade S; Conte, Michael S

2017-12-01

The objective of this study was to assess midterm functional status, wound healing, and in-hospital resource use among a prospective cohort of patients treated in a tertiary hospital, multidisciplinary Center for Limb Preservation. Data were prospectively gathered on all consecutive admissions to the Center for Limb Preservation from July 2013 to October 2014 with follow-up data collection through January 2016. Limbs were staged using the Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) threatened limb classification scheme at the time of hospital admission. Patients with nonatherosclerotic vascular disorders, acute limb ischemia, and trauma were excluded. The cohort included 128 patients with 157 threatened limbs; 8 limbs with unstageable disease were excluded. Mean age (±standard deviation [SD]) was 66 (±13) years, and median follow-up duration (interquartile range) was 395 (80-635) days. Fifty percent (n = 64/128) of patients were readmitted at least once, with a readmission rate of 20% within 30 days of the index admission. Mean total number of admissions per patient (±SD) was 1.9 ± 1.2, with mean (±SD) cumulative length of stay (cLOS) of 17.1 (±17.9) days. During follow-up, 25% of limbs required a vascular reintervention, and 45% developed recurrent wounds. There was no difference in the rate of readmission, vascular reintervention, or wound recurrence by initial WIfI stage (P > .05). At the end of the study period, 23 (26%) were alive and nonambulatory; in 20%, functional status was missing. On both univariate and multivariate analysis, end-stage renal disease and prior functional status predicted ability to ambulate independently (P < .05). WIfI stage was associated with major amputation (P = .01) and cLOS (P = .002) but not with time to wound healing. Direct hospital (inpatient) cost per limb saved was significantly higher in stage 4 patients (P < .05 for all time periods). WIfI stage was associated with cumulative in-hospital costs at 1 year and for the overall follow-up period. Among a population of patients admitted to a tertiary hospital limb preservation service, WIfI stage was predictive of midterm freedom from amputation, cLOS, and hospital costs but not of ambulatory functional status, time to wound healing, or wound recurrence. Patients presenting with limb-threatening conditions require significant inpatient care, have a high frequency of repeated hospitalizations, and are at significant risk for recurrent wounds and leg symptoms at later times. Stage 4 patients require the most intensive care and have the highest initial and aggregate hospital costs per limb saved. However, limb salvage can be achieved in these patients with a dedicated multidisciplinary team approach. Published by Elsevier Inc.

Vertical Distribution of Aerosols and Water Vapor Using CRISM Limb Observations

NASA Astrophysics Data System (ADS)

Smith, M. D.; Wolff, M. J.; Clancy, R. T.; CRISM Science; Operations Teams

2011-12-01

Near-infrared spectra taken in a limb-viewing geometry by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) on-board the Mars Reconnaissance Orbiter (MRO) provide a useful tool for probing atmospheric structure. Specifically, the observed radiance as a function of wavelength and height above the limb allows the vertical distribution of both dust and ice aerosols to be retrieved. These data serve as an important supplement to the aerosol profiling provided by the MRO/MCS instrument allowing independent validation and giving additional information on particle physical and scattering properties through multi-wavelength studies. A total of at least ten CRISM limb observations have been taken so far covering a full Martian year. Each set of limb observations nominally contains about four dozen scans across the limb giving pole-to-pole coverage for two orbits at roughly 100 and 290 W longitude over the Tharsis and Syrtis/Hellas regions, respectively. At each longitude, limb scans are spaced roughly 10 degrees apart in latitude, with a vertical spatial resolution on the limb of roughly 800 m. Radiative transfer modeling is used to model the observations. We compute synthetic CRISM limb spectra using a discrete-ordinates radiative transfer code that accounts for multiple scattering from aerosols and accounts for spherical geometry of the limb observations by integrating the source functions along curved paths in that coordinate system. Retrieved are 14-point vertical profiles for dust and water ice aerosols with resolution of 0.4 scale heights between one and six scale heights above the surface. After the aerosol retrieval is completed, the abundances of CO2 (or surface pressure) and H2O gas are retrieved by matching the depth of absorption bands at 2000 nm for carbon dioxide and at 2600 nm for water vapor. In addition to the column abundance of water vapor, limited information on its vertical structure can also be retrieved depending on the signal available from aerosol scattering. Significant differences are seen in the retrieved vertical profiles of dust and water ice as a function of season. Dust typically extends to higher altitudes during the perihelion season. Ice aerosols are often observed to cap the dust layer during all seasons. Water vapor is observed to be deeply mixed in the perihelion season and confined near the surface in the aphelion season. The CRISM limb-geometry observations support the quantitative retrieval of aerosol and gas vertical profiles. These quantities cannot be retrieved using nadir observations, and they enable the study of important new science questions. The CRISM limbs also serve as a valuable supplement to the MRO/MCS limb profiles, enabling validation and multi-wavelength comparisons. Additional CRISM limb-geometry sets will continue to be taken approximately every two months (~30 degrees of Ls) as operations allow.

Functional expansion of sensorimotor representation and structural reorganization of callosal connections in lower limb amputees.

PubMed

Simões, Elington L; Bramati, Ivanei; Rodrigues, Erika; Franzoi, Ana; Moll, Jorge; Lent, Roberto; Tovar-Moll, Fernanda

2012-02-29

Previous studies have indicated that amputation or deafferentation of a limb induces functional changes in sensory (S1) and motor (M1) cortices, related to phantom limb pain. However, the extent of cortical reorganization after lower limb amputation in patients with nonpainful phantom phenomena remains uncertain. In this study, we combined functional magnetic resonance (fMRI) and diffusion tensor imaging (DTI) to investigate the existence and extent of cortical and callosal plasticity in these subjects. Nine "painless" patients with lower limb amputation and nine control subjects (sex- and age-matched) underwent a 3-T MRI protocol, including fMRI with somatosensory stimulation. In amputees, we observed an expansion of activation maps of the stump in S1 and M1 of the deafferented hemisphere, spreading to neighboring regions that represent the trunk and upper limbs. We also observed that tactile stimulation of the intact foot in amputees induced a greater activation of ipsilateral S1, when compared with controls. These results demonstrate a functional remapping of S1 in lower limb amputees. However, in contrast to previous studies, these neuroplastic changes do not appear to be dependent on phantom pain but do also occur in those who reported only the presence of phantom sensation without pain. In addition, our findings indicate that amputation of a limb also induces changes in the cortical representation of the intact limb. Finally, DTI analysis showed structural changes in the corpus callosum of amputees, compatible with the hypothesis that phantom sensations may depend on inhibitory release in the sensorimotor cortex.

Whole limb kinematics are preferentially conserved over individual joint kinematics after peripheral nerve injury

PubMed Central

Chang, Young-Hui; Auyang, Arick G.; Scholz, John P.; Nichols, T. Richard

2009-01-01

Summary Biomechanics and neurophysiology studies suggest whole limb function to be an important locomotor control parameter. Inverted pendulum and mass-spring models greatly reduce the complexity of the legs and predict the dynamics of locomotion, but do not address how numerous limb elements are coordinated to achieve such simple behavior. As a first step, we hypothesized whole limb kinematics were of primary importance and would be preferentially conserved over individual joint kinematics after neuromuscular injury. We used a well-established peripheral nerve injury model of cat ankle extensor muscles to generate two experimental injury groups with a predictable time course of temporary paralysis followed by complete muscle self-reinnervation. Mean trajectories of individual joint kinematics were altered as a result of deficits after injury. By contrast, mean trajectories of limb orientation and limb length remained largely invariant across all animals, even with paralyzed ankle extensor muscles, suggesting changes in mean joint angles were coordinated as part of a long-term compensation strategy to minimize change in whole limb kinematics. Furthermore, at each measurement stage (pre-injury, paralytic and self-reinnervated) step-by-step variance of individual joint kinematics was always significantly greater than that of limb orientation. Our results suggest joint angle combinations are coordinated and selected to stabilize whole limb kinematics against short-term natural step-by-step deviations as well as long-term, pathological deviations created by injury. This may represent a fundamental compensation principle allowing animals to adapt to changing conditions with minimal effect on overall locomotor function. PMID:19837893

Scintigraphic Tracking of Allogeneic Mesenchymal Stem Cells in the Distal Limb After Intra-Arterial Injection in Standing Horses.

PubMed

Espinosa, Pablo; Spriet, Mathieu; Sole, Albert; Walker, Naomi J; Vaughan, Betsy; Galuppo, Larry D

2016-07-01

To assess the feasibility of intra-arterial administration of allogeneic mesenchymal stem cells (MSC) in the median artery of standing horses and evaluate the distribution and retention of radiolabeled cells. In vivo experimental study. Six research horses. Technetium(99m) -HexaMethyl-Propylene-Amine Oxime-labeled MSC were injected under ultrasound guidance in the median artery of 6 front limbs of 3 horses, standing under sedation. Scintigraphic images were obtained at the time of injection, and at 1, 6, and 24 hours postinjection. Six additional limbs from 3 horses were similarly injected with unlabeled MSC. Ultrasound was performed the following day for assessment of vascular changes. Intra-arterial injection was performed successfully in 11 of 12 limbs. In 1 limb, partial periarterial injection compromised the success of the procedure. Homogeneous distribution of radiolabeled MSC was observed through the entire distal limb, including within the hoof. Partial venous thrombosis was found in both groups of horses, but was subjectively less severe in horses injected with unlabeled MSC. No lameness was observed. Transient swelling of the distal limb occurred in only 1 limb. Intra-arterial injection of MSC can be performed in standing horses under sedation and successfully distribute MSC to the distal limb. A risk of periarterial injection was identified but can be reduced with proper sedation, local anesthesia, and increased experience. Partial venous thrombosis was observed as a complication, but did not cause changes of clinical importance, other than rare transient swelling. © Copyright 2016 by The American College of Veterinary Surgeons.

Failure to activate the in-hospital emergency team: causes and outcomes.

PubMed

Barbosa, Vera; Gomes, Ernestina; Vaz, Senio; Azevedo, Gustavo; Fernandes, Gonçalo; Ferreira, Amélia; Araujo, Rui

2016-01-01

To determine the incidence of afferent limb failure of the in-hospital Medical Emergency Team, characterizing it and comparing the mortality between the population experiencing afferent limb failure and the population not experiencing afferent limb failure. A total of 478 activations of the Medical Emergency Team of Hospital Pedro Hispano occurred from January 2013 to July 2015. A sample of 285 activations was obtained after excluding incomplete records and activations for patients with less than 6 hours of hospitalization. The sample was divided into two groups: the group experiencing afferent limb failure and the group not experiencing afferent limb failure of the Medical Emergency Team. Both populations were characterized and compared. Statistical significance was set at p ≤ 0.05. Afferent limb failure was observed in 22.1% of activations. The causal analysis revealed significant differences in Medical Emergency Team activation criteria (p = 0.003) in the group experiencing afferent limb failure, with higher rates of Medical Emergency Team activation for cardiac arrest and cardiovascular dysfunction. Regarding patient outcomes, the group experiencing afferent limb failure had higher immediate mortality rates and higher mortality rates at hospital discharge, with no significant differences. No significant differences were found for the other parameters. The incidence of cardiac arrest and the mortality rate were higher in patients experiencing failure of the afferent limb of the Medical Emergency Team. This study highlights the need for health units to invest in the training of all healthcare professionals regarding the Medical Emergency Team activation criteria and emergency medical response system operations.

Propulsion and braking in the study of asymmetry in able-bodied men's gaits.

PubMed

Potdevin, François; Gillet, Christophe; Barbier, Franck; Coello, Yann; Moretto, Pierre

2008-12-01

The present study was designed to test functional differences between both lower limbs in able-bodied gait according to fore-aft force impulse analyses and to assess the existence of a preferential lower limb for forward propulsion and braking. The leg that did more of the braking (Most Braking Limb) and the leg that did more of the propulsion (Most Propulsive Limb) were defined by the higher negative and positive impulses calculated from the anterior-posterior component of the ground reaction force. 24 adult men free of pain and injury to their lower extremities (M age =25.9 yr., SD=4.5) performed 10 walking trials on a 10-m walkway with two force plates flush mounted in the middle. The anterior-posterior component of the velocity of the center of mass (V(AP)) was calculated with the VICON system. Results highlighted two forms of asymmetry behaviour: although significant bilateral differences between the legs concerning the propulsive and braking impulses were found in all participants, 70.8% of the participants displayed a different Most Braking Limb than Most Propulsive Limb, whereas 25% used the same leg to produce both more propulsion and braking. High consistency was found in the behavioural strategy. Bilateral differences in V(AP) according to the gait cycle (Most Propulsive Limb vs Most Braking Limb) suggested a functional division of tasks between the two lower limbs for 70.8% of the participants. The study provides support for the relevancy of a functional categorization to highlight different asymmetry strategies in able-bodied gait.

Lower extremity sagittal joint moment production during split-belt treadmill walking

PubMed Central

Roemmich, Ryan T.; Stegemöller, Elizabeth L.; Hass, Chris J.

2012-01-01

The split-belt treadmill (SBT) has recently been used to rehabilitate locomotor asymmetries in clinical populations. However, the joint mechanics produced while walking on a SBT are not well-understood. The purpose of this study was to investigate the lower extremity sagittal joint moments produced by each limb during SBT walking and provide insight as to how these joint moment patterns may be useful in rehabilitating unilateral gait deficits. Thirteen healthy young volunteers walked on the SBT with the belts tied and in a “SPLIT” session in which one belt moved twice as fast as the other. Sagittal lower extremity joint moment and ground reaction force impulses were then calculated over the braking and propulsive phases of the gait cycle. Paired t-tests were performed to analyze magnitude differences between conditions (i.e. the fast and slow limbs during SPLIT vs. the same limb during tied-belt walking) and between the fast and slow limbs during SPLIT. During the SPLIT session, the fast limb produced higher ground reaction force and ankle moment impulses during the propulsive and braking phases, and lower knee moment impulses during the propulsive phase when compared to the slow limb. The knee moment impulse was also significantly higher during braking in the slow limb than in the fast limb. The mechanics of each limb during the SPLIT session also differed from the mechanics observed when the belt speeds were tied. Based on these findings, we suggest that each belt may have intrinsic value in rehabilitating specific unilateral locomotor deficits. PMID:22985473

Conditional inactivation of Has2 reveals a crucial role for hyaluronan in skeletal growth, patterning, chondrocyte maturation and joint formation in the developing limb.

PubMed

Matsumoto, Kazu; Li, Yingcui; Jakuba, Caroline; Sugiyama, Yoshinori; Sayo, Tetsuya; Okuno, Misako; Dealy, Caroline N; Toole, Bryan P; Takeda, Junji; Yamaguchi, Yu; Kosher, Robert A

2009-08-01

The glycosaminoglycan hyaluronan (HA) is a structural component of extracellular matrices and also interacts with cell surface receptors to directly influence cell behavior. To explore functions of HA in limb skeletal development, we conditionally inactivated the gene for HA synthase 2, Has2, in limb bud mesoderm using mice that harbor a floxed allele of Has2 and mice carrying a limb mesoderm-specific Prx1-Cre transgene. The skeletal elements of Has2-deficient limbs are severely shortened, indicating that HA is essential for normal longitudinal growth of all limb skeletal elements. Proximal phalanges are duplicated in Has2 mutant limbs indicating an involvement of HA in patterning specific portions of the digits. The growth plates of Has2-deficient skeletal elements are severely abnormal and disorganized, with a decrease in the deposition of aggrecan in the matrix and a disruption in normal columnar cellular relationships. Furthermore, there is a striking reduction in the number of hypertrophic chondrocytes and in the expression domains of markers of hypertrophic differentiation in the mutant growth plates, indicating that HA is necessary for the normal progression of chondrocyte maturation. In addition, secondary ossification centers do not form in the central regions of Has2 mutant growth plates owing to a failure of hypertrophic differentiation. In addition to skeletal defects, the formation of synovial joint cavities is defective in Has2-deficient limbs. Taken together, our results demonstrate that HA has a crucial role in skeletal growth, patterning, chondrocyte maturation and synovial joint formation in the developing limb.

Gender differences in limited duty time for lower limb injury.

PubMed

Holsteen, K K; Choi, Y S; Bedno, S A; Nelson, D A; Kurina, L M

2018-02-16

Among active-duty military personnel, lower limb musculoskeletal injuries and related conditions (injuries) frequently arise as unintended consequences of physical training. These injuries are particularly common among women. The practical impact of such injuries on temporary military occupational disability has not been estimated with precision on a large scale. To determine the proportion of service time compromised by limited duty days attributable to lower limb injuries, characterize the time affected by these limitations in terms of specific lower limb region and compare the limited duty time between male and female soldiers. Administrative data and individual limited duty assignments (profiles) were obtained for active-duty US Army personnel who served in 2014. Lower limb injury-related profiles were used to calculate the percent of person-time requiring duty limitations by gender and body region. The study group was 568 753 soldiers of whom 14% were women. Nearly 13% of service days for active-duty US Army soldiers required limited duty for lower limb injuries during 2014. Knee injuries were responsible for 45% of those days. Within integrated military occupations, female soldiers experienced 27-57% more time on limited duty for lower limb injuries compared with men. The substantial amount of limited duty for lower limb musculoskeletal injuries among soldiers highlights the need for improvement in training-related injury screening, prevention and timely treatment with particular attention to knee injuries. The excessive impact of lower limb injuries on female soldiers' occupational functions should be a surveillance priority in the current environment of expanding gender-integrated training. Published by Oxford University Press on behalf of The Society of Occupational Medicine 2017.

Predictive Value of Upper Limb Muscles and Grasp Patterns on Functional Outcome in Cervical Spinal Cord Injury.

PubMed

Velstra, Inge-Marie; Bolliger, Marc; Krebs, Jörg; Rietman, Johan S; Curt, Armin

2016-05-01

To determine which single or combined upper limb muscles as defined by the International Standards for the Neurological Classification of Spinal Cord Injury (ISNCSCI); upper extremity motor score (UEMS) and the Graded Redefined Assessment of Strength, Sensibility, and Prehension (GRASSP), best predict upper limb function and independence in activities of daily living (ADLs) and to assess the predictive value of qualitative grasp movements (QlG) on upper limb function in individuals with acute tetraplegia. As part of a Europe-wide, prospective, longitudinal, multicenter study ISNCSCI, GRASSP, and Spinal Cord Independence Measure (SCIM III) scores were recorded at 1 and 6 months after SCI. For prediction of upper limb function and ADLs, a logistic regression model and unbiased recursive partitioning conditional inference tree (URP-CTREE) were used. Results: Logistic regression and URP-CTREE revealed that a combination of ISNCSCI and GRASSP muscles (to a maximum of 4) demonstrated the best prediction (specificity and sensitivity ranged from 81.8% to 96.0%) of upper limb function and identified homogenous outcome cohorts at 6 months. The URP-CTREE model with the QlG predictors for upper limb function showed similar results. Prediction of upper limb function can be achieved through a combination of defined, specific upper limb muscles assessed in the ISNCSCI and GRASSP. A combination of a limited number of proximal and distal muscles along with an assessment of grasping movements can be applied for clinical decision making for rehabilitation interventions and clinical trials. © The Author(s) 2015.

ATHLETE: Lunar Cargo Unloading from a High Deck

NASA Technical Reports Server (NTRS)

Wilcox, Brian H.

2010-01-01

As part of the NASA Exploration Technology Development Program, the Jet Propulsion Laboratory is developing a vehicle called ATHLETE: the All-Terrain Hex-Limbed Extra-Terrestrial Explorer. Each vehicle is based on six wheels at the ends of six multi-degree-of freedom limbs. Because each limb has enough degrees of freedom for use as a general-purpose leg, the wheels can be locked and used as feet to walk out of excessively soft or other extreme terrain. Since the vehicle has this alternative mode of traversing through or at least out of extreme terrain, the wheels and wheel actuators can be sized for nominal terrain. There are substantial mass savings in the wheel and wheel actuators associated with designing for nominal instead of extreme terrain. These mass savings are at least comparable-to or larger-than the extra mass associated with the articulated limbs. As a result, the entire mobility system, including wheels and limbs, can be lighter than a conventional all-terrain mobility chassis. A side benefit of this approach is that each limb has sufficient degrees-of freedom to be used as a general-purpose manipulator (hence the name "limb" instead of "leg"). Our prototype ATHLETE vehicles have quick-disconnect tool adapters on the limbs that allow tools to be drawn out of a "tool belt" and maneuvered by the limb. A power-take-off from the wheel actuates the tools, so that they can take advantage of the 1+ horsepower motor in each wheel to enable drilling, gripping or other power-tool functions.

ATHLETE: a Cargo and Habitat Transporter for the Moon

NASA Technical Reports Server (NTRS)

Wilcox, Brian H.

2009-01-01

As part of the NASA Exploration Technology Development Program, the Jet Propulsion Laboratory is developing a vehicle called ATHLETE: the All-Terrain Hex-Limbed Extra-Terrestrial Explorer. The vehicle concept is based on six wheels at the ends of six multi-degree-of-freedom limbs. Because each limb has enough degrees of freedom for use as a general-purpose leg, the wheels can be locked and used as feet to walk out of excessively soft or other extreme terrain. Since the vehicle has this alternative mode of traversing through (or at least out of) extreme terrain, the wheels and wheel actuators can be sized only for nominal terrain. There are substantial mass savings in the wheels and wheel actuators associated with designing for nominal instead of extreme terrain. These mass savings are comparable-to or larger-than the extra mass associated with the articulated limbs. As a result, the entire mobility system, including wheels and limbs, can be about 25 percent lighter than a conventional mobility chassis for planetary exploration. A side benefit of this approach is that each limb has sufficient degrees-of-freedom for use as a general-purpose manipulator (hence the name "limb" instead of "leg"). Our prototype ATHLETE vehicles have quick-disconnect tool adapters on the limbs that allow tools to be drawn out of a "tool belt" and maneuvered by the limb. A rotating power-take-off from the wheel actuates the tools, so that they can take advantage of the 1-plus-horsepower motor in each wheel to enable drilling, gripping or other power-tool functions.

Molecular anatomy of the developing limb in the coquí frog, Eleutherodactylus coqui.

PubMed

Gross, Joshua B; Kerney, Ryan; Hanken, James; Tabin, Clifford J

2011-01-01

The vertebrate limb demonstrates remarkable similarity in basic organization across phylogenetically disparate groups. To gain further insight into how this morphological similarity is maintained in different developmental contexts, we explored the molecular anatomy of size-reduced embryos of the Puerto Rican coquí frog, Eleutherodactylus coqui. This animal demonstrates direct development, a life-history strategy marked by rapid progression from egg to adult and absence of a free-living, aquatic larva. Nonetheless, coquí exhibits a basal anuran limb structure, with four toes on the forelimb and five toes on the hind limb. We investigated the extent to which coquí limb bud development conforms to the model of limb development derived from amniote studies. Toward this end, we characterized dynamic patterns of expression for 13 critical patterning genes across three principle stages of limb development. As expected, most genes demonstrate expression patterns that are essentially unchanged compared to amniote species. For example, we identified an EcFgf8-expression domain within the apical ectodermal ridge (AER). This expression pattern defines a putatively functional AER signaling domain, despite the absence of a morphological ridge in coquí embryos. However, two genes, EcMeis2 and EcAlx4, demonstrate altered domains of expression, which imply a potential shift in gene function between coquí frogs and amniote model systems. Unexpectedly, several genes thought to be critical for limb patterning in other systems, including EcFgf4, EcWnt3a, EcWnt7a, and EcGremlin, demonstrated no evident expression pattern in the limb at the three stages we analyzed. The absence of EcFgf4 and EcWnt3a expression during limb patterning is perhaps not surprising, given that neither gene is critical for proper limb development in the mouse, based on knockout and expression analyses. In contrast, absence of EcWnt7a and EcGremlin is surprising, given that expression of these molecules appears to be absolutely essential in all other model systems so far examined. Although this analysis substantiates the existence of a core set of ancient limb-patterning molecules, which likely mediate identical functions across highly diverse vertebrate forms, it also reveals remarkable evolutionary flexibility in the genetic control of a conserved morphological pattern across evolutionary time. © 2011 Wiley Periodicals, Inc.

[Domestic external fixator application in the treatment of limb deformities: 7 289 cases application report].

PubMed

Qin, S H; Guo, B F; Zheng, X J; Jiao, S F; Xia, H T; Peng, A M; Pan, Q; Zang, J C; Wang, Z J

2017-09-01

Objective: To discuss the clinical application and effects of domestic external fixator in the treatment of patients with malformations of limbs. Methods: A total of 7 289 patients with malformation of limbs who had been operated in Qin Sihe orthopedic surgery team from January 1989 to June 2016 were retrospective analyzed. The patients were treated with domestic external fixator, including 4 033 males and 3 256 females, aging from 2 to 82 years with a mean age of 23.4 years. There were 2 732 patients using Ilizarov external fixator, 4 713 patients using hybrid external fixator, 57 patients using monobrachial external fixator, 232 patients using Ilizarov external fixator and hybrid external fixator. The Ilizarov, hybrid and monobrachial external fixator were used in 67, 65 and 0 patients on the upper limbs and in 2 665, 4 616 and 57 patients on the lower limbs. There were 3 028 patients operated on the left limbs, 3 260 patients operated on the right limbs and 1 001 patients operated on the bilateral limbs. The top three types of diseases were sequelae of poliomyelitis, cerebral palsy and post-traumatic stress disorder peromely. Deformity types inclued talipes equinovarus, knee flexion deformity, cavus foot and so on. Results: All the patients were followed up for a period of 2.5 months to 22.4 years, with an average follow-up time of 5.4 years. All of the external fixators were used for single once, and there was no substitute for external fixator quality problem. All the patients were completed surgery goal until removing external fixation except 1 patient gave up treatment and 1 removed the fixator because of metal allergy. The common complications included wire or pin infection and joint movement limitation and so on. Conclusions: The domestic external fixator developed and produced based on the characteristics of Chinese limb deformity disability. The domestic external fixator can be used to treat kinds of limb deformities with the advantages of practical, economical, adjustable, universal and portable. The domestic external fixator could meet the clinical demand for fixation of the osteotomy end of the limbs, the correction of the deformity, the repair of the defects and the limb lengthening.

Vertical distribution of Martian aerosols from SPICAM/Mars-Express limb observations

NASA Astrophysics Data System (ADS)

Fedorova, A.; Korablev, O.; Bertaux, J.-L.; Rodin, A.; Perrier, S.; Moroz, V. I.

Limb spectroscopic observations provide invaluable information about vertical distribution of main atmospheric components in the Martian atmosphere, in particular vertical distribution and structure of aerosols, which play an important role in the heat balance of the planet. Only limited set of successful limb spectroscopic observations have been carried out on Mars so far, including those by MGS/TES spectrometer and Thermoscan and Auguste experiments of Phobos mission. Currently SPICAM instrument onboard Mars-Express spacecraft has accomplished several sequences of limb observations. First analysis of limb sounding data received by SPICAM IR and UV channels, which imply the presence of fine, deep, optically thin aerosol fraction extended over broad range of altitudes, is presented.

Cortical motor activity and reorganization following upper-limb amputation and subsequent targeted reinnervation.

PubMed

Chen, Albert; Yao, Jun; Kuiken, Todd; Dewald, Julius P A

2013-01-01

Previous studies have postulated that the amount of brain reorganization following peripheral injuries may be correlated with negative symptoms or consequences. However, it is unknown whether restoring effective limb function may then be associated with further changes in the expression of this reorganization. Recently, targeted reinnervation (TR), a surgical technique that restores a direct neural connection from amputated sensorimotor nerves to new peripheral targets such as muscle, has been successfully applied to upper-limb amputees. It has been shown to be effective in restoring both peripheral motor and sensory functions via the reinnervated nerves as soon as a few months after the surgery. However, it was unclear whether TR could also restore normal cortical motor representations for control of the missing limb. To answer this question, we used high-density electroencephalography (EEG) to localize cortical activity related to cued motor tasks generated by the intact and missing limb. Using a case study of 3 upper-limb amputees, 2 of whom went through pre and post-TR experiments, we present unique quantitative evidence for the re-mapping of motor representations for the missing limb closer to their original locations following TR. This provides evidence that an effective restoration of peripheral function from TR can be linked to the return of more normal cortical expression for the missing limb. Therefore, cortical mapping may be used as a potential guide for monitoring rehabilitation following peripheral injuries.

Five-Strand versus Four-Strand Hamstring Tendon Graft Technique for Anterior Cruciate Ligament Reconstruction: A Biomechanical Comparison.

PubMed

Vaillant, Eric R; Parks, Brent G; Camire, Lyn M; Hinton, Richard Y

2017-11-01

The aim of this article is to compare diameter and stiffness, displacement, and strain in a five-strand versus four-strand hamstring graft for anterior cruciate ligament reconstruction. Eight matched pairs of lower extremities underwent four-strand or five-strand hamstring graft reconstruction. Diameter was significantly higher in the five-strand versus the four-strand construct ( p  = 0.002). No significant difference was found between the groups in construct displacement or stiffness. Significantly higher strain was observed in the inner limb versus the outer limb in the four-strand construct ( p  = 0.001) and in the inner limb versus the fifth limb in the 5-strand construct ( p  = 0.004). A fifth limb added to a four-strand hamstring graft significantly increased graft diameter but did not significantly change stiffness or displacement, suggesting that attachment of additional graft material via suture did not provide for full incorporation of the added limb into the graft at time zero. The inner limb in both constructs absorbed significantly greater load than did other limbs. The use of suture to attach additional material to a four-strand hamstring graft may not contribute to improved biomechanical qualities of the graft at time zero. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Push-off reactions in recovery after tripping discriminate young subjects, older non-fallers and older fallers.

PubMed

Pijnappels, Mirjam; Bobbert, Maarten F; van Dieën, Jaap H

2005-06-01

Tripping is a major cause for falls, especially in the elderly. This study investigated whether falls in the elderly can be attributed to inadequate push-off reactions by the support limb in the recovery after a trip. Twelve young (20-34 years) and eleven older (65-72 years) men and women walked over a platform and were tripped several times over an obstacle that suddenly appeared from the floor. Kinematics and ground reactions forces of the support limb during push-off were measured of falls and successful recoveries. Young subjects did not fall. The older subjects were divided into a group of four non-fallers and seven fallers. Older fallers showed insufficient reduction of the angular momentum during push-off and less proper placement of the recovery limb. This was due to a lower rate of change of moment generation in all support limb joints and a lower peak ankle moment. Onset of knee moment generation was slightly delayed in older fallers. Improvement over trials was ascribed to better positioning of the recovery limb, as no clear differences were seen in the joint moments of the support limb. In conclusion, the contribution of the support limb to prevent a fall after tripping is decreased in older adults. Lower limb strength could be an underlying factor and strength training might help to reduce fall risk.

The impact of lower limb chronic oedema on patients' quality of life.

PubMed

Greene, Adelene; Meskell, Pauline

2017-06-01

This study aimed to explore patients' perceptions regarding the impact that lower limb chronic oedema has on their quality of life (QoL). A quantitative descriptive design was used to collect data from patients with lower limb chronic oedema. A condition-specific validated questionnaire was distributed to a purposive sample (n = 122) through manual lymphatic drainage/vascular/health clinics in Ireland. Results indicated that patients with lower limb chronic oedema experience a wide range of physical problems such as limb heaviness (74%, n = 66), weakness (44%, n = 40) and pain (38%, n = 34). Additionally, difficulties with walking (53%, n = 48), standing (51%, n = 46) and bending (45%, n = 40) were reported. Concerns regarding poor body image were strongly evident (76%, n = 68). Difficulties finding clothing/footwear to fit oedematous limb(s) were reported (59%, n = 53), in addition to finding clothes that participants would like to wear (64%, n = 58). Emotional symptoms of irritability (42%, n = 38), anxiety (41%, n = 37) and tension (40%, n = 36) were reported. Over half of the participants (55%, n = 49) stated that their chronic swelling affected their social functioning and their ability to engage in leisure activities. This study has identified that lower limb chronic oedema has significant psychological, social and physical implications for persons' QoL. © 2016 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Gender related Long-term Differences after Open Infrainguinal Surgery for Critical Limb Ischemia.

PubMed

Lejay, A; Schaeffer, M; Georg, Y; Lucereau, B; Roussin, M; Girsowicz, E; Delay, C; Schwein, A; Thaveau, F; Geny, B; Chakfe, N

2015-10-01

The role of gender on long-term infrainguinal open surgery outcomes still remains uncertain in critical limb ischemia patients. The aim of this study is to evaluate the gender-specific differences in patient characteristics and long-term clinical outcomes in terms of survival, primary patency and limb salvage among patients undergoing infrainguinal open surgery for CLI. All consecutive patients undergoing infrainguinal open surgery for critical limb ischemia between 2003 and 2012 were included. Survival, limb salvage and primary patency rates were assessed. Independent outcome determinants were identified by the Cox proportional hazard ratio using age and gender as adjustment factors. 584 patients (269 women and 315 men, mean age 76 and 71 years respectively) underwent 658 infrainguinal open surgery (313 in women and 345 in men). Survival rate at 6 years was lower among women compared to men with 53.5% vs 70.9% (p < 0.001). The same applied to primary patency (35.9% vs 52.4%, p < 0.001) and limb salvage (54.3% vs 81.1%, p < 0.001) at 6 years. Female-gender was an independent factor predicting death (hazard ratio 1.50), thrombosis (hazard ratio 2.37) and limb loss (hazard ratio 7.05) in age and gender-adjusted analysis. Gender-related disparity in critical limb ischemia open surgical revascularization outcomes still remains. Copyright © 2015 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Steady state temperature distribution in dermal regions of an irregular tapered shaped human limb with variable eccentricity.

PubMed

Agrawal, M; Pardasani, K R; Adlakha, N

2014-08-01

The investigators in the past have developed some models of temperature distribution in the human limb assuming it as a regular circular or elliptical tapered cylinder. But in reality the limb is not of regular tapered cylindrical shape. The radius and eccentricity are not same throughout the limb. In view of above a model of temperature distribution in the irregular tapered elliptical shaped human limb is proposed for a three dimensional steady state case in this paper. The limb is assumed to be composed of multiple cylindrical substructures with variable radius and eccentricity. The mathematical model incorporates the effect of blood mass flow rate, metabolic activity and thermal conductivity. The outer surface is exposed to the environment and appropriate boundary conditions have been framed. The finite element method has been employed to obtain the solution. The temperature profiles have been computed in the dermal layers of a human limb and used to study the effect of shape, microstructure and biophysical parameters on temperature distribution in human limbs. The proposed model is one of the most realistic model as compared to conventional models as this can be effectively employed to every regular and nonregular structures of the body with variable radius and eccentricity to study the thermal behaviour. Copyright © 2014 Elsevier Ltd. All rights reserved.

The axolotl limb blastema: cellular and molecular mechanisms driving blastema formation and limb regeneration in tetrapods

PubMed Central

McCusker, Catherine; Bryant, Susan V.

2015-01-01

Abstract The axolotl is one of the few tetrapods that are capable of regenerating complicated biological structures, such as complete limbs, throughout adulthood. Upon injury the axolotl generates a population of regeneration‐competent limb progenitor cells known as the blastema, which will grow, establish pattern, and differentiate into the missing limb structures. In this review we focus on the crucial early events that occur during wound healing, the neural−epithelial interactions that drive the formation of the early blastema, and how these mechanisms differ from those of other species that have restricted regenerative potential, such as humans. We also discuss how the presence of cells from the different axes of the limb is required for the continued growth and establishment of pattern in the blastema as described in the polar coordinate model, and how this positional information is reprogrammed in blastema cells during regeneration. Multiple cell types from the mature limb stump contribute to the blastema at different stages of regeneration, and we discuss the contribution of these types to the regenerate with reference to whether they are “pattern‐forming” or “pattern‐following” cells. Lastly, we explain how an engineering approach will help resolve unanswered questions in limb regeneration, with the goal of translating these concepts to developing better human regenerative therapies. PMID:27499868

Lmx1b-targeted cis-regulatory modules involved in limb dorsalization.

PubMed

Haro, Endika; Watson, Billy A; Feenstra, Jennifer M; Tegeler, Luke; Pira, Charmaine U; Mohan, Subburaman; Oberg, Kerby C

2017-06-01

Lmx1b is a homeodomain transcription factor responsible for limb dorsalization. Despite striking double-ventral (loss-of-function) and double-dorsal (gain-of-function) limb phenotypes, no direct gene targets in the limb have been confirmed. To determine direct targets, we performed a chromatin immunoprecipitation against Lmx1b in mouse limbs at embryonic day 12.5 followed by next-generation sequencing (ChIP-seq). Nearly 84% ( n =617) of the Lmx1b-bound genomic intervals (LBIs) identified overlap with chromatin regulatory marks indicative of potential cis -regulatory modules (PCRMs). In addition, 73 LBIs mapped to CRMs that are known to be active during limb development. We compared Lmx1b-bound PCRMs with genes regulated by Lmx1b and found 292 PCRMs within 1 Mb of 254 Lmx1b-regulated genes. Gene ontological analysis suggests that Lmx1b targets extracellular matrix production, bone/joint formation, axonal guidance, vascular development, cell proliferation and cell movement. We validated the functional activity of a PCRM associated with joint-related Gdf5 that provides a mechanism for Lmx1b-mediated joint modification and a PCRM associated with Lmx1b that suggests a role in autoregulation. This is the first report to describe genome-wide Lmx1b binding during limb development, directly linking Lmx1b to targets that accomplish limb dorsalization. © 2017. Published by The Company of Biologists Ltd.

[Mirror, mirror of the wall: mirror therapy in the treatment of phantom limbs and phantom limb pain].

PubMed

Casale, Roberto; Furnari, Anna; Lamberti, Raul Coelho; Kouloulas, Efthimios; Hagenberg, Annegret; Mallik, Maryam

2015-01-01

Phantom limb and phantom limb pain control are pivotal points in the sequence of intervention to bring the amputee to functional autonomy. The alterations of perception and sensation, the pain of the residual limb and the phantom limb are therefore aspects of amputation that should be taken into account in the "prise en charge" of these patients. Within the more advanced physical therapies to control phantom and phantom limb pain there is the use of mirrors (mirror therapy). This article willfocus on its use and on the possible side effects induced by the lack of patient selection and a conflict of body schema restoration through mirror therapy with concurrent prosthetic training and trauma acceptance. Advice on the need to select patients before treatment decisions, with regard to their psychological as well as clinical profile (including time since amputation and clinical setting), and the need to be aware of the possible adverse effects matching different and somehow conflicting therapeutic approaches, are put forward. Thus a coordinated sequence of diagnostic, prognostic and therapeutic procedures carried out by an interdisciplinary rehabilitation team that works globally on all patients' problems is fundamental in the management of amputees and phantom limb pain. Further studies and the development of a multidisciplinary network to study this and other applications of mirror therapy are needed.

Bilateral Proprioceptive Evaluation in Individuals With Unilateral Chronic Ankle Instability

PubMed Central

Sousa, Andreia S. P.; Leite, João; Costa, Bianca; Santos, Rubim

2017-01-01

Context: Despite extensive research on chronic ankle instability, the findings regarding proprioception have been conflicting and focused only on the injured limb. Also, the different components of proprioception have been evaluated in isolation. Objective: To evaluate bilateral ankle proprioception in individuals with unilateral ankle instability. Design: Cohort study. Setting: Research laboratory center in a university. Patients or Other Participants: Twenty-four individuals with a history of unilateral ankle sprain and chronic ankle instability (mechanical ankle instability group, n = 10; functional ankle instability [FAI] group, n = 14) and 20 controls. Main Outcome Measure(s): Ankle active and passive joint position sense, kinesthesia, and force sense. Results: We observed a significant interaction between the effects of limb and group for kinesthesia (F = 3.27, P = .049). Increased error values were observed in the injured limb of the FAI group compared with the control group (P = .031, Cohen d = 0.47). Differences were also evident for force sense (F = 9.31, P < .001): the FAI group demonstrated increased error versus the control group (injured limb: P < .001, Cohen d = 1.28; uninjured limb: P = .009, Cohen d = 0.89) and the mechanical ankle instability group (uninjured limb: P = .023, Cohen d = 0.76). Conclusions: Individuals with unilateral FAI had increased error ipsilaterally (injured limb) for inversion movement detection (kinesthesia) and evertor force sense and increased error contralaterally (uninjured limb) for evertor force sense. PMID:28318316

FOXO4-Knockdown Suppresses Oxidative Stress-Induced Apoptosis of Early Pro-Angiogenic Cells and Augments Their Neovascularization Capacities in Ischemic Limbs

PubMed Central

Nakayoshi, Takaharu; Sasaki, Ken-ichiro; Kajimoto, Hidemi; Koiwaya, Hiroshi; Ohtsuka, Masanori; Ueno, Takafumi; Chibana, Hidetoshi; Itaya, Naoki; Sasaki, Masahiro; Yokoyama, Shinji; Fukumoto, Yoshihiro; Imaizumi, Tsutomu

2014-01-01

The effects of therapeutic angiogenesis by intramuscular injection of early pro-angiogenic cells (EPCs) to ischemic limbs are unsatisfactory. Oxidative stress in the ischemic limbs may accelerate apoptosis of injected EPCs, leading to less neovascularization. Forkhead transcription factor 4 (FOXO4) was reported to play a pivotal role in apoptosis signaling of EPCs in response to oxidative stress. Accordingly, we assessed whether FOXO4-knockdown EPCs (FOXO4KD-EPCs) could suppress the oxidative stress-induced apoptosis and augment the neovascularization capacity in ischemic limbs. We transfected small interfering RNA targeted against FOXO4 of human EPCs to generate FOXO4KD-EPCs and confirmed a successful knockdown. FOXO4KD-EPCs gained resistance to apoptosis in response to hydrogen peroxide in vitro. Oxidative stress stained by dihydroethidium was stronger for the immunodeficient rat ischemic limb tissue than for the rat non-ischemic one. Although the number of apoptotic EPCs injected into the rat ischemic limb was greater than that of apoptotic EPCs injected into the rat non-ischemic limb, FOXO4KD-EPCs injected into the rat ischemic limb brought less apoptosis and more neovascularization than EPCs. Taken together, the use of FOXO4KD-EPCs with resistance to oxidative stress-induced apoptosis may be a new strategy to augment the effects of therapeutic angiogenesis by intramuscular injection of EPCs. PMID:24663349

Anatomical Network Comparison of Human Upper and Lower, Newborn and Adult, and Normal and Abnormal Limbs, with Notes on Development, Pathology and Limb Serial Homology vs. Homoplasy

PubMed Central

Diogo, Rui; Esteve-Altava, Borja; Smith, Christopher; Boughner, Julia C.; Rasskin-Gutman, Diego

2015-01-01

How do the various anatomical parts (modules) of the animal body evolve into very different integrated forms (integration) yet still function properly without decreasing the individual’s survival? This long-standing question remains unanswered for multiple reasons, including lack of consensus about conceptual definitions and approaches, as well as a reasonable bias toward the study of hard tissues over soft tissues. A major difficulty concerns the non-trivial technical hurdles of addressing this problem, specifically the lack of quantitative tools to quantify and compare variation across multiple disparate anatomical parts and tissue types. In this paper we apply for the first time a powerful new quantitative tool, Anatomical Network Analysis (AnNA), to examine and compare in detail the musculoskeletal modularity and integration of normal and abnormal human upper and lower limbs. In contrast to other morphological methods, the strength of AnNA is that it allows efficient and direct empirical comparisons among body parts with even vastly different architectures (e.g. upper and lower limbs) and diverse or complex tissue composition (e.g. bones, cartilages and muscles), by quantifying the spatial organization of these parts—their topological patterns relative to each other—using tools borrowed from network theory. Our results reveal similarities between the skeletal networks of the normal newborn/adult upper limb vs. lower limb, with exception to the shoulder vs. pelvis. However, when muscles are included, the overall musculoskeletal network organization of the upper limb is strikingly different from that of the lower limb, particularly that of the more proximal structures of each limb. Importantly, the obtained data provide further evidence to be added to the vast amount of paleontological, gross anatomical, developmental, molecular and embryological data recently obtained that contradicts the long-standing dogma that the upper and lower limbs are serial homologues. In addition, the AnNA of the limbs of a trisomy 18 human fetus strongly supports Pere Alberch's ill-named "logic of monsters" hypothesis, and contradicts the commonly accepted idea that birth defects often lead to lower integration (i.e. more parcellation) of anatomical structures. PMID:26452269

Musculoskeletal Complaints in Transverse Upper Limb Reduction Deficiency and Amputation in The Netherlands: Prevalence, Predictors, and Effect on Health.

PubMed

Postema, Sietke G; Bongers, Raoul M; Brouwers, Michael A; Burger, Helena; Norling-Hermansson, Liselotte M; Reneman, Michiel F; Dijkstra, Pieter U; van der Sluis, Corry K

2016-07-01

(1) To determine the prevalence of musculoskeletal complaints (MSCs) in individuals with upper limb absence in The Netherlands, (2) to assess the health status of individuals with upper limb absence in general and in relation to the presence of MSCs, and (3) to explore the predictors of development of MSCs and MSC-related disability in this population. Cross-sectional study: national survey. Twelve rehabilitation centers and orthopedic workshops. Individuals (n=263; mean age, 50.7±16.7y; 60% men) ≥18 years old, with transverse upper limb reduction deficiency (42%) or amputation (58%) at or proximal to the carpal level (response, 45%) and 108 individuals without upper limb reduction deficiency or amputation (n=108; mean age, 50.6±15.7y; 65% men) (N=371). Not applicable. Point and year prevalence of MSCs, MSC-related disability (Pain Disability Index), and general health perception and mental health (RAND-36 subscales). Point and year prevalence of MSCs were almost twice as high in individuals with upper limb absence (57% and 65%, respectively) compared with individuals without upper limb absence (27% and 34%, respectively) and were most often located in the nonaffected limb and upper back/neck. MSCs were associated with decreased general health perception and mental health and higher perceived upper extremity work demands. Prosthesis use was not related to presence of MSCs. Clinically relevant predictors of MSCs were middle age, being divorced/widowed, and lower mental health. Individuals with upper limb absence experienced more MSC-related disability than individuals without upper limb absence. Higher age, more pain, lower general and mental health, and not using a prosthesis were related to higher disability. Presence of MSCs is a frequent problem in individuals with upper limb absence and is associated with decreased general and mental health. Mental health and physical work demands should be taken into account when assessing such a patient. Clinicians should note that MSC-related disability increases with age. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Unilateral Plantar Flexors Static-Stretching Effects on Ipsilateral and Contralateral Jump Measures

PubMed Central

da Silva, Josinaldo Jarbas; Behm, David George; Gomes, Willy Andrade; Silva, Fernando Henrique Domingues de Oliveira; Soares, Enrico Gori; Serpa, Érica Paes; Vilela Junior, Guanis de Barros; Lopes, Charles Ricardo; Marchetti, Paulo Henrique

2015-01-01

The aim of this study was to evaluate the acute effects of unilateral ankle plantar flexors static-stretching (SS) on the passive range of movement (ROM) of the stretched limb, surface electromyography (sEMG) and single-leg bounce drop jump (SBDJ) performance measures of the ipsilateral stretched and contralateral non-stretched lower limbs. Seventeen young men (24 ± 5 years) performed SBDJ before and after (stretched limb: immediately post-stretch, 10 and 20 minutes and non-stretched limb: immediately post-stretch) unilateral ankle plantar flexor SS (6 sets of 45s/15s, 70-90% point of discomfort). SBDJ performance measures included jump height, impulse, time to reach peak force, contact time as well as the sEMG integral (IEMG) and pre-activation (IEMGpre-activation) of the gastrocnemius lateralis. Ankle dorsiflexion passive ROM increased in the stretched limb after the SS (pre-test: 21 ± 4° and post-test: 26.5 ± 5°, p < 0.001). Post-stretching decreases were observed with peak force (p = 0.029), IEMG (P<0.001), and IEMGpre-activation (p = 0.015) in the stretched limb; as well as impulse (p = 0.03), and jump height (p = 0.032) in the non-stretched limb. In conclusion, SS effectively increased passive ankle ROM of the stretched limb, and transiently (less than 10 minutes) decreased muscle peak force and pre-activation. The decrease of jump height and impulse for the non-stretched limb suggests a SS-induced central nervous system inhibitory effect. Key points When considering whether or not to SS prior to athletic activities, one must consider the potential positive effects of increased ankle dorsiflexion motion with the potential deleterious effects of power and muscle activity during a simple jumping task or as part of the rehabilitation process. Since decreased jump performance measures can persist for 10 minutes in the stretched leg, the timing of SS prior to performance must be taken into consideration. Athletes, fitness enthusiasts and therapists should also keep in mind that SS one limb has generalized effects upon contralateral limbs as well. PMID:25983580

Anatomical Network Comparison of Human Upper and Lower, Newborn and Adult, and Normal and Abnormal Limbs, with Notes on Development, Pathology and Limb Serial Homology vs. Homoplasy.

PubMed

Diogo, Rui; Esteve-Altava, Borja; Smith, Christopher; Boughner, Julia C; Rasskin-Gutman, Diego

2015-01-01

How do the various anatomical parts (modules) of the animal body evolve into very different integrated forms (integration) yet still function properly without decreasing the individual's survival? This long-standing question remains unanswered for multiple reasons, including lack of consensus about conceptual definitions and approaches, as well as a reasonable bias toward the study of hard tissues over soft tissues. A major difficulty concerns the non-trivial technical hurdles of addressing this problem, specifically the lack of quantitative tools to quantify and compare variation across multiple disparate anatomical parts and tissue types. In this paper we apply for the first time a powerful new quantitative tool, Anatomical Network Analysis (AnNA), to examine and compare in detail the musculoskeletal modularity and integration of normal and abnormal human upper and lower limbs. In contrast to other morphological methods, the strength of AnNA is that it allows efficient and direct empirical comparisons among body parts with even vastly different architectures (e.g. upper and lower limbs) and diverse or complex tissue composition (e.g. bones, cartilages and muscles), by quantifying the spatial organization of these parts-their topological patterns relative to each other-using tools borrowed from network theory. Our results reveal similarities between the skeletal networks of the normal newborn/adult upper limb vs. lower limb, with exception to the shoulder vs. pelvis. However, when muscles are included, the overall musculoskeletal network organization of the upper limb is strikingly different from that of the lower limb, particularly that of the more proximal structures of each limb. Importantly, the obtained data provide further evidence to be added to the vast amount of paleontological, gross anatomical, developmental, molecular and embryological data recently obtained that contradicts the long-standing dogma that the upper and lower limbs are serial homologues. In addition, the AnNA of the limbs of a trisomy 18 human fetus strongly supports Pere Alberch's ill-named "logic of monsters" hypothesis, and contradicts the commonly accepted idea that birth defects often lead to lower integration (i.e. more parcellation) of anatomical structures.

Nerves and Tissue Repair.

DTIC Science & Technology

1994-07-01

axolotl limbs are transected the concentration of transferrin in the distal limb tissue declines rapidly and limb regeneration stops. These results...transferrin binding and expression of the transferrin gene in cells of axolotl peripheral nerve indicate that both uptake and synthesis of this factor occur

The classification of phocomelia.

PubMed

Tytherleigh-Strong, G; Hooper, G

2003-06-01

We studied 24 patients with 44 phocomelic upper limbs. Only 11 limbs could be grouped in the classification system of Frantz and O' Rahilly. The non-classifiable limbs were further studied and their characteristics identified. It is confirmed that phocomelia is not an intercalary defect.

Psychosomatic treatment of phantom limb pain with post-traumatic stress disorder: a case report.

PubMed

Muraoka, M; Komiyama, H; Hosoi, M; Mine, K; Kubo, C

1996-08-01

The successful treatment of severe left lower limb phantom pain is reported. Hypnosis and antidepressant drugs were the basis for the treatment which controlled the phantom limb pain and an associated post-traumatic stress disorder.

Ectopic expression of Msx-2 in posterior limb bud mesoderm impairs limb morphogenesis while inducing BMP-4 expression, inhibiting cell proliferation, and promoting apoptosis.

PubMed

Ferrari, D; Lichtler, A C; Pan, Z Z; Dealy, C N; Upholt, W B; Kosher, R A

1998-05-01

During early stages of chick limb development, the homeobox-containing gene Msx-2 is expressed in the mesoderm at the anterior margin of the limb bud and in a discrete group of mesodermal cells at the midproximal posterior margin. These domains of Msx-2 expression roughly demarcate the anterior and posterior boundaries of the progress zone, the highly proliferating posterior mesodermal cells underneath the apical ectodermal ridge (AER) that give rise to the skeletal elements of the limb and associated structures. Later in development as the AER loses its activity, Msx-2 expression expands into the distal mesoderm and subsequently into the interdigital mesenchyme which demarcates the developing digits. The domains of Msx-2 expression exhibit considerably less proliferation than the cells of the progress zone and also encompass several regions of programmed cell death including the anterior and posterior necrotic zones and interdigital mesenchyme. We have thus suggested that Msx-2 may be in a regulatory network that delimits the progress zone by suppressing the morphogenesis of the regions of the limb mesoderm in which it is highly expressed. In the present study we show that ectopic expression of Msx-2 via a retroviral expression vector in the posterior mesoderm of the progress zone from the time of initial formation of the limb bud severely impairs limb morphogenesis. Msx-2-infected limbs are typically very narrow along the anteroposterior axis, are occasionally truncated, and exhibit alterations in the pattern of formation of skeletal elements, indicating that as a consequence of ectopic Msx-2 expression the morphogenesis of large portions of the posterior mesoderm has been suppressed. We further show that Msx-2 impairs limb morphogenesis by reducing cell proliferation and promoting apoptosis in the regions of the posterior mesoderm in which it is ectopically expressed. The domains of ectopic Msx-2 expression in the posterior mesoderm also exhibit ectopic expression of BMP-4, a secreted signaling molecule that is coexpressed with Msx-2 during normal limb development in the anterior limb mesoderm, the posterior necrotic zone, and interdigital mesenchyme. This indicates that Msx-2 regulates BMP-4 expression and that the suppressive effects of Msx-2 on limb morphogenesis might be mediated in part by BMP-4. These studies indicate that during normal limb development Msx-2 is a key component of a regulatory network that delimits the boundaries of the progress zone by suppressing the morphogenesis of the regions of the limb mesoderm in which it is highly expressed, thus restricting the outgrowth and formation of skeletal elements and associated structures to the progress zone. We also report that rather large numbers of apoptotic cells as well as proliferating cells are present throughout the AER during all stages of normal limb development we have examined, indicating that many of the cells of the AER are continuously undergoing programmed cell death at the same time that new AER cells are being generated by cell proliferation. Thus, a balance between cell proliferation and programmed cell death may play a very important role in maintaining the activity of the AER. Copyright 1998 Academic Press.

Vertical Distribution of Aersols and Water Vapor Using CRISM Limb Observations

NASA Technical Reports Server (NTRS)

Smith, Michael D.; Wolff, Michael J.; Clancy, R. Todd

2011-01-01

Near-infrared spectra taken in a limb-viewing geometry by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) on-board the Mars Reconnaissance Orbiter (MRO) provide a useful tool for probing atmospheric structure. Specifically, the observed radiance as a function of wavelength and height above the limb allows the vertical distribution of both dust and ice aerosols to be retrieved. These data serve as an important supplement to the aerosol profiling provided by the MRO/MCS instrument allowing independent validation and giving additional information on particle physical and scattering properties through multi-wavelength studies. A total of at least ten CRISM limb observations have been taken so far covering a full Martian year. Each set of limb observations nominally contains about four dozen scans across the limb giving pole-to-pole coverage for two orbits at roughly 100 and 290 W longitude over the Tharsis and Syrtis/Hellas regions, respectively. At each longitude, limb scans are spaced roughly 10 degrees apart in latitude, with a vertical spatial resolution on the limb of roughly 800 m. Radiative transfer modeling is used to model the observations. We compute synthetic CRISM limb spectra using a discrete-ordinates radiative transfer code that accounts for multiple scattering from aerosols and accounts for spherical geometry of the limb observations by integrating the source functions along curved paths in that coordinate system. Retrieved are 14-point vertical profiles for dust and water ice aerosols with resolution of 0.4 scale heights between one and six scale heights above the surface. After the aerosol retrieval is completed, the abundances of C02 (or surface pressure) and H20 gas are retrieved by matching the depth of absorption bands at 2000 nm for carbon dioxide and at 2600 run for water vapor. In addition to the column abundance of water vapor, limited information on its vertical structure can also be retrieved depending on the signal available from aerosol scattering.

Absence of the genicular arterial anastomosis as generally depicted in textbooks.

PubMed

Sabalbal, M; Johnson, M; McAlister, V

2013-09-01

Textbook representations of the genicular arterial anastomosis show a large direct communication between the descending branch of the lateral circumflex femoral artery (DBLCFA) and a genicular branch of the popliteal artery but this is not compatible with clinical experience. The aim of this study was to determine whether the arterial anastomosis at the knee is sufficient, in the event of traumatic disruption of the superficial femoral artery, to infuse protective agents or to place a stent to restore flow to the lower leg. Dissection of ten cadaveric lower limbs was performed to photograph the arterial anatomy from the inguinal ligament to the tibial tubercle. Anastomosis with branches of the popliteal artery was classified as: 'direct communication', 'approaching communication' or 'no evident communication'. A constant descending artery in the lateral thigh (LDAT) was found to have five types of origin: Type 1 (2/10 limbs) involved the lateral circumflex femoral branch of the femoral artery, Type 2 (3/10 limbs) the lateral circumflex femoral branch of the profunda femoris artery, Type 3 (1/10 limbs) the femoral artery, Type 4 (3/10 limbs) the superficial femoral artery and Type 5 (2/10 limbs) the profunda femoris artery. In one limb, there were two descending arteries (Types 4 and 5). Collateral circulation at the knee was also variable: direct communicating vessels (3/10 limbs); approaching vessels with possible communication via capillaries (5/10 limbs); no evident communication (2/10 limbs). Communicating vessels, if present, are too small to provide immediate collateral circulation. Modern representations of the genicular arterial anastomosis are inaccurate, derived commonly from an idealised image that first appeared Gray's Anatomy in 1910. The afferent vessel is not the DBLCFA. The majority of subjects have the potential to recruit collateral circulation via the LDAT following gradual obstruction to normal arterial flow, which may be important if the LDAT is removed for bypass or flap surgery. A direct communication is rarely present and is never as robust as generally depicted in textbooks.

The benefit of limb cloud imaging for infrared limb sounding of tropospheric trace gases

NASA Astrophysics Data System (ADS)

Adams, S.; Spang, R.; Preusse, P.; Heinemann, G.

2009-06-01

Advances in detector technology enable a new generation of infrared limb sounders to measure 2-D images of the atmosphere. A proposed limb cloud imager (LCI) mode will detect clouds with a spatial resolution unprecedented for limb sounding. For the inference of temperature and trace gas distributions, detector pixels of the LCI have to be combined into super-pixels which provide the required signal-to-noise and information content for the retrievals. This study examines the extent to which tropospheric coverage can be improved in comparison to limb sounding using a fixed field of view with the size of the super-pixels, as in conventional limb sounders. The study is based on cloud topographies derived from (a) IR brightness temperatures (BT) of geostationary weather satellites in conjunction with ECMWF temperature profiles and (b) ice and liquid water content data of the Consortium for Small-scale Modeling-Europe (COSMO-EU) of the German Weather Service. Limb cloud images are simulated by matching the cloud topography with the limb sounding line of sight (LOS). The analysis of the BT data shows that the reduction of the spatial sampling along the track has hardly any effect on the gain in information. The comparison between BT and COSMO-EU data identifies the strength of both data sets, which are the representation of the horizontal cloud extent for the BT data and the reproduction of the cloud amount for the COSMO-EU data. The results of the analysis of both data sets show the great advantage of the cloud imager. However, because both cloud data sets do not present the complete fine structure of the real cloud fields in the atmosphere it is assumed that the results tend to underestimate the increase in information. In conclusion, real measurements by such an instrument may result in an even higher benefit for tropospheric limb retrievals.

LADEE UVS (UltraViolet Visible Spectrometer) and the Search for Lunar Exospheric Dust: A Detailed Spectral Analysis

NASA Technical Reports Server (NTRS)

Wooden, Diane H.; Cook, Amanda; Colaprete, Anthony; Shirley, Mark; Vargo, Kara; Elphic, Richard C.; Hermalyn, Brendan; Stubbs, Timothy John; Glenar, David A.

2014-01-01

The Lunar Atmosphere and Dust Environment Explorer (LADEE) executed science observations in lunar orbit spanning 2013-Oct-16- 2014-04-18 UT. LADEE's Ultraviolet/Visible Spectrometer (UVS) studies the composition and temporal variations of the tenuous lunar exosphere and dust environment, utilizing two sets of optics: a limb-viewing telescope, and a solar-viewer. The limb-viewing telescope observes illuminated dust and emitting gas species while the Sun is just behind the lunar limb. The solar viewer, with its diffuser, allows UVS to also stare directly at the solar disk as it approaches the limb, sampling progressively lower exosphere altitudes. Solar viewer "Occultation" activities occur at the lunar sunrise limb, as the LADEE spacecraft passes into the lunar night side, facing the Sun (the spacecraft orbit is near-equatorial retrograde). A loss of transmission of sunlight occurs by the occultation of dust grains along the line-of-sight. So-called "Inertial Limb" activities have the limb-viewing telescope pointed at the lit exosphere just after the Sun has set. Inertial Limb activities follow a similar progression of diminishing sampling altitudes but hold the solar elongation angle constant so the zodiacal light contribution remains constant while seeking to observe the weak lunar horizon glow. On the dark side of the moon, "Sodium Tail" activities pointed the limb-viewing telescope in the direction of the Moon's sodium tail (similar to anti-sunward), during different lunar phases. Of the UVS data sets, these show the largest excess of scattered blue light, indicative of the presence of small (approximately 100 nm) dust grains in the tail. Correlations are sought between dust in the sodium tail and meteor streams and magnetotail crossings to investigate impact- versus electrostatic-lofting. Once lofted, nanoparticles can become charged and picked up by the solar wind. The LADEE UVS Occultation, Inertial Limb, and Sodium Tail spectral datasets provide evidence of a lunar dust exosphere.

Cross-bridge kinetics of fast and slow fibres of cat jaw and limb muscles: correlations with myosin subunit composition.

PubMed

Hoh, Joseph F Y; Li, Zhao-Bo; Qin, Han; Hsu, Michael K H; Rossmanith, Gunther H

2007-01-01

Mechanical properties of the jaw-closing muscles of the cat are poorly understood. These muscles are known to differ in myosin and fibre type compositions from limb muscles. This work aims to correlate mechanical properties of single fibres in cat jaw and limb muscles with their myosin subunit compositions. The stiffness minimum frequency, f(min), which reflects isometric cross-bridge kinetics, was measured in Ca(2+)-activated glycerinated fast and slow fibres from cat jaw and limb muscles for temperatures ranging between 15 and 30 degrees C by mechanical perturbation analysis. At 15 degrees C, f(min) was 0.5 Hz for limb-slow fibres, 4-6 Hz for jaw-slow fibres, and 10-13 Hz for limb-fast and jaw-fast fibres. The activation energy for f(min) obtained from the slope of the Arrhenius plot for limb-slow fibres was 30-40% higher than values for the other three types of fibres. SDS-PAGE and western blotting using highly specific antibodies verified that limb-fast fibres contained IIA or IIX myosin heavy chain (MyHC). Jaw-fast fibres expressed masticatory MyHC while both jaw-fast and jaw-slow fibres expressed masticatory myosin light chains (MLCs). The nucleotide sequences of the 3' ends of the slow MyHC cDNAs isolated from cat masseter and soleus cDNA libraries showed identical coding and 3'-untranslated regions, suggesting that jaw-slow and limb-slow fibres express the same slow MyHC gene. We conclude that the isometric cross-bridge cycling kinetics of jaw-fast and limb-fast fibres detected by f(min) are indistinguishable in spite of differences in MyHC and light chain compositions. However, jaw-slow fibres, in which the same slow MyHCs are found in combination with MLCs of the jaw type, show enhanced cross-bridge cycling kinetics and reduced activation energy for cross-bridge detachment.

Geometric Morphometrics on Gene Expression Patterns Within Phenotypes: A Case Example on Limb Development

PubMed Central

Martínez-Abadías, Neus; Mateu, Roger; Niksic, Martina; Russo, Lucia; Sharpe, James

2016-01-01

How the genotype translates into the phenotype through development is critical to fully understand the evolution of phenotypes. We propose a novel approach to directly assess how changes in gene expression patterns are associated with changes in morphology using the limb as a case example. Our method combines molecular biology techniques, such as whole-mount in situ hybridization, with image and shape analysis, extending the use of Geometric Morphometrics to the analysis of nonanatomical shapes, such as gene expression domains. Elliptical Fourier and Procrustes-based semilandmark analyses were used to analyze the variation and covariation patterns of the limb bud shape with the expression patterns of two relevant genes for limb morphogenesis, Hoxa11 and Hoxa13. We devised a multiple thresholding method to semiautomatically segment gene domains at several expression levels in large samples of limb buds from C57Bl6 mouse embryos between 10 and 12 postfertilization days. Besides providing an accurate phenotyping tool to quantify the spatiotemporal dynamics of gene expression patterns within developing structures, our morphometric analyses revealed high, non-random, and gene-specific variation undergoing canalization during limb development. Our results demonstrate that Hoxa11 and Hoxa13, despite being paralogs with analogous functions in limb patterning, show clearly distinct dynamic patterns, both in shape and size, and are associated differently with the limb bud shape. The correspondence between our results and already well-established molecular processes underlying limb development confirms that this morphometric approach is a powerful tool to extract features of development regulating morphogenesis. Such multilevel analyses are promising in systems where not so much molecular information is available and will advance our understanding of the genotype–phenotype map. In systematics, this knowledge will increase our ability to infer how evolution modified a common developmental pattern to generate a wide diversity of morphologies, as in the vertebrate limb. PMID:26377442

Peak knee biomechanics and limb symmetry following unilateral anterior cruciate ligament reconstruction: Associations of walking gait and jump-landing outcomes.

PubMed

Pfeiffer, Steven J; Blackburn, J Troy; Luc-Harkey, Brittney; Harkey, Matthew S; Stanley, Laura E; Frank, Barnett; Padua, Darin; Marshall, Stephen W; Spang, Jeffrey T; Pietrosimone, Brian

2018-03-01

Aberrant walking-gait and jump-landing biomechanics may influence the development of post-traumatic osteoarthritis and increase the risk of a second anterior cruciate ligament injury, respectively. It remains unknown if individuals who demonstrate altered walking-gait biomechanics demonstrate similar altered biomechanics during jump-landing. Our aim was to determine associations in peak knee biomechanics and limb-symmetry indices between walking-gait and jump-landing tasks in individuals with a unilateral anterior cruciate ligament reconstruction. Thirty-five individuals (74% women, 22.1 [3.4] years old, 25 [3.89] kg/m 2 ) with an anterior cruciate ligament reconstruction performed 5-trials of self-selected walking-gait and jump-landing. Peak kinetics and kinematics were extracted from the first 50% of stance phase during walking-gait and first 100 ms following ground contact for jump-landing. Pearson product-moment (r) and Spearman's Rho (ρ) analyses were used to evaluate relationships between outcome measures. Significance was set a priori (P ≤ 0.05). All associations between walking-gait and jump-landing for the involved limb, along with the majority of associations for limb-symmetry indices and the uninvolved limb, were negligible and non-statistically significant. There were weak significant associations for instantaneous loading rate (ρ = 0.39, P = 0.02) and peak knee abduction angle (ρ = 0.36, p = 0.03) uninvolved limb, as well as peak abduction displacement limb-symmetry indices (ρ= - 0.39, p = 0.02) between walking-gait and jump-landing. No systematic associations were found between walking-gait and jump-landing biomechanics for either limb or limb-symmetry indices in people with unilateral anterior cruciate ligament reconstruction. Individuals with an anterior cruciate ligament reconstruction who demonstrate high-involved limb loading or asymmetries during jump-landing may not demonstrate similar biomechanics during walking-gait. Copyright © 2018 Elsevier Ltd. All rights reserved.

An official American Thoracic Society/European Respiratory Society statement: update on limb muscle dysfunction in chronic obstructive pulmonary disease.

PubMed

Maltais, François; Decramer, Marc; Casaburi, Richard; Barreiro, Esther; Burelle, Yan; Debigaré, Richard; Dekhuijzen, P N Richard; Franssen, Frits; Gayan-Ramirez, Ghislaine; Gea, Joaquim; Gosker, Harry R; Gosselink, Rik; Hayot, Maurice; Hussain, Sabah N A; Janssens, Wim; Polkey, Micheal I; Roca, Josep; Saey, Didier; Schols, Annemie M W J; Spruit, Martijn A; Steiner, Michael; Taivassalo, Tanja; Troosters, Thierry; Vogiatzis, Ioannis; Wagner, Peter D

2014-05-01

Limb muscle dysfunction is prevalent in chronic obstructive pulmonary disease (COPD) and it has important clinical implications, such as reduced exercise tolerance, quality of life, and even survival. Since the previous American Thoracic Society/European Respiratory Society (ATS/ERS) statement on limb muscle dysfunction, important progress has been made on the characterization of this problem and on our understanding of its pathophysiology and clinical implications. The purpose of this document is to update the 1999 ATS/ERS statement on limb muscle dysfunction in COPD. An interdisciplinary committee of experts from the ATS and ERS Pulmonary Rehabilitation and Clinical Problems assemblies determined that the scope of this document should be limited to limb muscles. Committee members conducted focused reviews of the literature on several topics. A librarian also performed a literature search. An ATS methodologist provided advice to the committee, ensuring that the methodological approach was consistent with ATS standards. We identified important advances in our understanding of the extent and nature of the structural alterations in limb muscles in patients with COPD. Since the last update, landmark studies were published on the mechanisms of development of limb muscle dysfunction in COPD and on the treatment of this condition. We now have a better understanding of the clinical implications of limb muscle dysfunction. Although exercise training is the most potent intervention to address this condition, other therapies, such as neuromuscular electrical stimulation, are emerging. Assessment of limb muscle function can identify patients who are at increased risk of poor clinical outcomes, such as exercise intolerance and premature mortality. Limb muscle dysfunction is a key systemic consequence of COPD. However, there are still important gaps in our knowledge about the mechanisms of development of this problem. Strategies for early detection and specific treatments for this condition are also needed.

An Official American Thoracic Society/European Respiratory Society Statement: Update on Limb Muscle Dysfunction in Chronic Obstructive Pulmonary Disease

PubMed Central

Maltais, François; Decramer, Marc; Casaburi, Richard; Barreiro, Esther; Burelle, Yan; Debigaré, Richard; Dekhuijzen, P. N. Richard; Franssen, Frits; Gayan-Ramirez, Ghislaine; Gea, Joaquim; Gosker, Harry R.; Gosselink, Rik; Hayot, Maurice; Hussain, Sabah N. A.; Janssens, Wim; Polkey, Micheal I.; Roca, Josep; Saey, Didier; Schols, Annemie M. W. J.; Spruit, Martijn A.; Steiner, Michael; Taivassalo, Tanja; Troosters, Thierry; Vogiatzis, Ioannis; Wagner, Peter D.

2014-01-01

Background: Limb muscle dysfunction is prevalent in chronic obstructive pulmonary disease (COPD) and it has important clinical implications, such as reduced exercise tolerance, quality of life, and even survival. Since the previous American Thoracic Society/European Respiratory Society (ATS/ERS) statement on limb muscle dysfunction, important progress has been made on the characterization of this problem and on our understanding of its pathophysiology and clinical implications. Purpose: The purpose of this document is to update the 1999 ATS/ERS statement on limb muscle dysfunction in COPD. Methods: An interdisciplinary committee of experts from the ATS and ERS Pulmonary Rehabilitation and Clinical Problems assemblies determined that the scope of this document should be limited to limb muscles. Committee members conducted focused reviews of the literature on several topics. A librarian also performed a literature search. An ATS methodologist provided advice to the committee, ensuring that the methodological approach was consistent with ATS standards. Results: We identified important advances in our understanding of the extent and nature of the structural alterations in limb muscles in patients with COPD. Since the last update, landmark studies were published on the mechanisms of development of limb muscle dysfunction in COPD and on the treatment of this condition. We now have a better understanding of the clinical implications of limb muscle dysfunction. Although exercise training is the most potent intervention to address this condition, other therapies, such as neuromuscular electrical stimulation, are emerging. Assessment of limb muscle function can identify patients who are at increased risk of poor clinical outcomes, such as exercise intolerance and premature mortality. Conclusions: Limb muscle dysfunction is a key systemic consequence of COPD. However, there are still important gaps in our knowledge about the mechanisms of development of this problem. Strategies for early detection and specific treatments for this condition are also needed. PMID:24787074

BMP-Mediated Functional Cooperation between Dlx5;Dlx6 and Msx1;Msx2 during Mammalian Limb Development

PubMed Central

Vieux-Rochas, Maxence; Bouhali, Kamal; Mantero, Stefano; Garaffo, Giulia; Provero, Paolo; Astigiano, Simonetta; Barbieri, Ottavia; Caratozzolo, Mariano F.; Tullo, Apollonia; Guerrini, Luisa; Lallemand, Yvan; Robert, Benoît

2013-01-01

The Dlx and Msx homeodomain transcription factors play important roles in the control of limb development. The combined disruption of Msx1 and Msx2, as well as that of Dlx5 and Dlx6, lead to limb patterning defects with anomalies in digit number and shape. Msx1;Msx2 double mutants are characterized by the loss of derivatives of the anterior limb mesoderm which is not observed in either of the simple mutants. Dlx5;Dlx6 double mutants exhibit hindlimb ectrodactyly. While the morphogenetic action of Msx genes seems to involve the BMP molecules, the mode of action of Dlx genes still remains elusive. Here, examining the limb phenotypes of combined Dlx and Msx mutants we reveal a new Dlx-Msx regulatory loop directly involving BMPs. In Msx1;Dlx5;Dlx6 triple mutant mice (TKO), beside the expected ectrodactyly, we also observe the hallmark morphological anomalies of Msx1;Msx2 double mutants suggesting an epistatic role of Dlx5 and Dlx6 over Msx2. In Msx2;Dlx5;Dlx6 TKO mice we only observe an aggravation of the ectrodactyly defect without changes in the number of the individual components of the limb. Using a combination of qPCR, ChIP and bioinformatic analyses, we identify two Dlx/Msx regulatory pathways: 1) in the anterior limb mesoderm a non-cell autonomous Msx-Dlx regulatory loop involves BMP molecules through the AER and 2) in AER cells and, at later stages, in the limb mesoderm the regulation of Msx2 by Dlx5 and Dlx6 occurs also cell autonomously. These data bring new elements to decipher the complex AER-mesoderm dialogue that takes place during limb development and provide clues to understanding the etiology of congenital limb malformations. PMID:23382810

BMP-mediated functional cooperation between Dlx5;Dlx6 and Msx1;Msx2 during mammalian limb development.

PubMed

Vieux-Rochas, Maxence; Bouhali, Kamal; Mantero, Stefano; Garaffo, Giulia; Provero, Paolo; Astigiano, Simonetta; Barbieri, Ottavia; Caratozzolo, Mariano F; Tullo, Apollonia; Guerrini, Luisa; Lallemand, Yvan; Robert, Benoît; Levi, Giovanni; Merlo, Giorgio R

2013-01-01

The Dlx and Msx homeodomain transcription factors play important roles in the control of limb development. The combined disruption of Msx1 and Msx2, as well as that of Dlx5 and Dlx6, lead to limb patterning defects with anomalies in digit number and shape. Msx1;Msx2 double mutants are characterized by the loss of derivatives of the anterior limb mesoderm which is not observed in either of the simple mutants. Dlx5;Dlx6 double mutants exhibit hindlimb ectrodactyly. While the morphogenetic action of Msx genes seems to involve the BMP molecules, the mode of action of Dlx genes still remains elusive. Here, examining the limb phenotypes of combined Dlx and Msx mutants we reveal a new Dlx-Msx regulatory loop directly involving BMPs. In Msx1;Dlx5;Dlx6 triple mutant mice (TKO), beside the expected ectrodactyly, we also observe the hallmark morphological anomalies of Msx1;Msx2 double mutants suggesting an epistatic role of Dlx5 and Dlx6 over Msx2. In Msx2;Dlx5;Dlx6 TKO mice we only observe an aggravation of the ectrodactyly defect without changes in the number of the individual components of the limb. Using a combination of qPCR, ChIP and bioinformatic analyses, we identify two Dlx/Msx regulatory pathways: 1) in the anterior limb mesoderm a non-cell autonomous Msx-Dlx regulatory loop involves BMP molecules through the AER and 2) in AER cells and, at later stages, in the limb mesoderm the regulation of Msx2 by Dlx5 and Dlx6 occurs also cell autonomously. These data bring new elements to decipher the complex AER-mesoderm dialogue that takes place during limb development and provide clues to understanding the etiology of congenital limb malformations.

Limb Preservation With Isolated Limb Infusion for Locally Advanced Nonmelanoma Cutaneous and Soft-Tissue Malignant Neoplasms

PubMed Central

Turaga, Kiran K.; Beasley, Georgia M.; Kane, John M.; Delman, Keith A.; Grobmyer, Stephen R.; Gonzalez, Ricardo J.; Letson, G. Douglas; Cheong, David; Tyler, Douglas S.; Zager, Jonathan S.

2015-01-01

Objective To demonstrate the efficacy of isolated limb infusion (ILI) in limb preservation for patients with locally advanced soft-tissue sarcomas and nonmelanoma cutaneous malignant neoplasms. Background Locally advanced nonmelanoma cutaneous and soft-tissue malignant neoplasms, including soft-tissue sarcomas of the extremities, can pose significant treatment challenges. We report our experience, including responses and limb preservation rates, using ILI in cutaneous and soft-tissue malignant neoplasms. Methods We identified 22 patients with cutaneous and soft-tissue malignant neoplasms who underwent 26 ILIs with melphalan and actinomycin from January 1, 2004, through December 31, 2009, from 5 institutions. Outcome measures included limb preservation and in-field response rates. Toxicity was measured using the Wieberdink scale and serum creatinine phosphokinase levels. Results The median age was 70 years (range, 19-92 years), and 12 patients (55%) were women. Fourteen patients (64%) had sarcomas, 7 (32%) had Merkel cell carcinoma, and 1 (5%) had squamous cell carcinoma. The median length of stay was 5.5 days (interquartile range, 4-8 days). Twenty-five of the 26 ILIs (96%) resulted in Wieberdink grade III or less toxicity, and 1 patient (4%) developed grade IV toxicity. The median serum creatinine phosphokinase level was 127 U/L for upper extremity ILIs and 93 U/L for lower extremity ILIs. Nineteen of 22 patients (86%) underwent successful limb preservation. The 3-month in-field response rate was 79% (21% complete and 58% partial), and the median follow-up was 8.6 months (range, 1-63 months). Five patients underwent resection of disease after an ILI, of whom 80% are disease free at a median of 8.6 months. Conclusions Isolated limb infusion provides an attractive alternative therapy for regional disease control and limb preservation in patients with limb-threatening cutaneous and soft-tissue malignant neoplasms. Short-term response rates appear encouraging, yet durability of response is unknown. PMID:21768436

Lower limb strength in sports-active transtibial amputees.

PubMed

Nolan, Lee

2009-09-01

The aim of this study was to compare hip strength in sports-active transtibial (TT) amputees, sedentary TT amputees and sports-active non-amputees. Three 'active' (exercising recreationally at least three times per week) TT amputees, four 'inactive' or sedentary TT amputees and nine 'active' able-bodied persons (AB) underwent concentric and eccentric hip flexion and extension strength testing on both limbs on an isokinetic dynamometer at 60 and 120 degrees /s. Little strength asymmetry was noted between the limbs of the active TT amputees (8% and 14% at 60 and 120 degrees /s, respectively), their residual limb being slightly stronger. Inactive TT amputees demonstrated up to 49% strength asymmetry, their intact limb being the stronger. Active TT amputees demonstrated greater peak hip torques (Nm/kg) for all conditions and speeds compared to inactive TT amputees. Peak hip torques (Nm/kg), were greater in the active TT amputees' residual limb compared to AB. While inactive TT amputees and AB had similar flexion/extension ratios, active TT amputees exhibited a lower ratio indicating overdeveloped hip extensors with respect to their hip flexors. It is not known whether this is due to the demands of sport or exercise with a prosthetic limb, or remaining residual thigh atrophy.

A comparison of upper limb amputees and patients with upper limb injuries using the Disability of the Arm, Shoulder and Hand (DASH).

PubMed

Davidson, Judith

To use the Disability of the Arm Shoulder and Hand (DASH) scale to measure the disability of patients with upper limb amputation(s) and to compare these to other upper limb injuries. All 274 patients over the age of 18 years presenting to Prince Henry Hospital in Sydney over a 4-year time frame were given the DASH assessment tool and asked to complete it under supervision of the Occupational Therapist. Patients with brachial plexus injuries, Complex Regional Pain Syndrome and bilateral upper limb amputations demonstrated significantly higher levels of disability to patients with unilateral upper limb amputations. Partial hand amputees reported a higher level of disability than major unilateral upper limb amputees. For the 48 patients who completed pre- and post-treatment assessments, there was a significant improvement in their health status. Further research is required to understand the factors that affect a patient's perceptions of their disability. Perhaps the definitive nature of an amputation and the immediate involvement of highly skilled health professionals serve to assist patients to accept their injury and therefore minimizes the level of disability.

Limb-use by foraging marine turtles, an evolutionary perspective

PubMed Central

McLeish, Don; Brooks, Andrew J.; Gaskell, John; Van Houtan, Kyle S.

2018-01-01

The use of limbs for foraging is documented in both marine and terrestrial tetrapods. These behaviors were once believed to be less likely in marine tetrapods due to the physical constraints of body plans adapted to locomotion in a fluid environment. Despite these obstacles, ten distinct types of limb-use while foraging have been previously reported in nine marine tetrapod families. Here, we expand the types of limb-use documented in marine turtles and put it in context with the diversity of marine tetrapods currently known to use limbs for foraging. Additionally, we suggest that such behaviors could have occurred in ancestral turtles, and thus, possibly extend the evolutionary timeline of limb-use behavior in marine tetrapods back approximately 70 million years. Through direct observation in situ and crowd-sourcing, we document the range of behaviors across habitats and prey types, suggesting its widespread occurrence. We argue the presence of these behaviors among marine tetrapods may be limited by limb mobility and evolutionary history, rather than foraging ecology or social learning. These behaviors may also be remnant of ancestral forelimb-use that have been maintained due to a semi-aquatic life history. PMID:29610708

Anti-gravity treadmill can promote aerobic exercise for lower limb osteoarthritis patients

PubMed Central

Kawae, Toshihiro; Mikami, Yukio; Fukuhara, Kouki; Kimura, Hiroaki; Adachi, Nobuo

2017-01-01

[Purpose] The anti-gravity treadmill (Alter-G®) allows the load on the lower limbs to be adjusted, which is considered useful for patients with lower limb osteoarthritis. The aim of the present study was to examine the effects of aerobic exercise using an anti-gravity treadmill in patients with lower limb osteoarthritis by using a cardiopulmonary exercise load monitoring system. [Subjects and Methods] The subjects were 20 patients with lower limb osteoarthritis. These subjects walked naturally for 8 minutes and then walked on the Alter-G for 8 minutes at their fastest speed at a load where lower limb pain was alleviated. [Results] Subjective and objective exercise intensity did not differ significantly between level ground walking and Alter-G walking neither before nor after walking. Pain before walking did not differ significantly between level ground walking and Alter-G walking, but pain after walking was significantly greater with level ground walking than with Alter-G walking. [Conclusion] Exercise therapy using an anti-gravity treadmill was useful for patients with lower limb osteoarthritis in terms of cardiopulmonary function, which suggested that this could become a new form of exercise therapy. PMID:28878480

Effect of Surface Reflectivity Variations On Uv-visible Limb Scattering Measurements of The Atmosphere

NASA Astrophysics Data System (ADS)

Oikarinen, L.

Solar UV and visible radiation scattered at the limb of the Earth's atmosphere is used for measuring density profiles of atmosperic trace gases. For example, the OSIRIS instrument on Odin and SCIAMACHY on Envisat use this technique. A limb-viewing instrument does not see Earth's surface or tropospheric clouds directly. However, in- direct light reflected from the surface or low altitude clouds can make up tens of per cents of the signal. Furthermore, the surface area that contributes to limb intensity ex- tends over 1000 km along the instrument line-of-sight and 200 km across it. Over this area surface reflectivity can vary from almost 0% to 100%. Inaccurate modelling of reflected intensity is a potential source of error in the trace gas retrieval. Generally, radiative transfer models used for analysing limb measure- ments have to assume that the surface has a constant albedo. We have used a three- dimensional Monte Carlo radiative transfer model to study the effects of surface vari- ation to limb radiance. Based on the simulations, we have developed an approximate method for averaging surface albedo for limb scattering measurements with the help of a simple single scattering radiative transfer model.

Upper limb motor function in young adults with spina bifida and hydrocephalus

PubMed Central

Salman, M. S.; Jewell, D.; Hetherington, R.; Spiegler, B. J.; MacGregor, D. L.; Drake, J. M.; Humphreys, R. P.; Gentili, F.

2011-01-01

Objective The objective of the study was to measure upper limb motor function in young adults with spina bifida meningomyelocele (SBM) and typically developing age peers. Method Participants were 26 young adults with SBM, with a Verbal or Performance IQ score of at least 70 on the Wechsler scales, and 27 age- and gender-matched controls. Four upper limb motor function tasks were performed under four different visual and cognitive challenge conditions. Motor independence was assessed by questionnaire. Results Fewer SBM than control participants obtained perfect posture and rebound scores. The SBM group performed less accurately and was more disrupted by cognitive challenge than controls on limb dysmetria tasks. The SBM group was slower than controls on the diadochokinesis task. Adaptive motor independence was related to one upper limb motor task, arm posture, and upper rather than lower spinal lesions were associated with less motor independence. Conclusions Young adults with SBM have significant limitations in upper limb function and are more disrupted by some challenges while performing upper limb motor tasks. Within the group of young adults with SBM, upper spinal lesions compromise motor independence more than lower spinal lesions. PMID:19672605

Local dynamic stability of lower extremity joints in lower limb amputees during slope walking.

PubMed

Chen, Jin-Ling; Gu, Dong-Yun

2013-01-01

Lower limb amputees have a higher fall risk during slope walking compared with non-amputees. However, studies on amputees' slope walking were not well addressed. The aim of this study was to identify the difference of slope walking between amputees and non-amputees. Lyapunov exponents λS was used to estimate the local dynamic stability of 7 transtibial amputees' and 7 controls' lower extremity joint kinematics during uphill and downhill walking. Compared with the controls, amputees exhibited significantly lower λS in hip (P=0.04) and ankle (P=0.01) joints of the sound limb, and hip joints (P=0.01) of the prosthetic limb during uphill walking, while they exhibited significantly lower λS in knee (P=0.02) and ankle (P=0.03) joints of the sound limb, and hip joints (P=0.03) of the prosthetic limb during downhill walking. Compared with amputees level walking, they exhibited significantly lower λS in ankle joints of the sound limb during both uphill (P=0.01) and downhill walking (P=0.01). We hypothesized that the better local dynamic stability of amputees was caused by compensation strategy during slope walking.

Comparative Transcriptional Profiling of the Axolotl Limb Identifies a Tripartite Regeneration-Specific Gene Program

PubMed Central

Knapp, Dunja; Schulz, Herbert; Rascon, Cynthia Alexander; Volkmer, Michael; Scholz, Juliane; Nacu, Eugen; Le, Mu; Novozhilov, Sergey; Tazaki, Akira; Protze, Stephanie; Jacob, Tina; Hubner, Norbert; Habermann, Bianca; Tanaka, Elly M.

2013-01-01

Understanding how the limb blastema is established after the initial wound healing response is an important aspect of regeneration research. Here we performed parallel expression profile time courses of healing lateral wounds versus amputated limbs in axolotl. This comparison between wound healing and regeneration allowed us to identify amputation-specific genes. By clustering the expression profiles of these samples, we could detect three distinguishable phases of gene expression – early wound healing followed by a transition-phase leading to establishment of the limb development program, which correspond to the three phases of limb regeneration that had been defined by morphological criteria. By focusing on the transition-phase, we identified 93 strictly amputation-associated genes many of which are implicated in oxidative-stress response, chromatin modification, epithelial development or limb development. We further classified the genes based on whether they were or were not significantly expressed in the developing limb bud. The specific localization of 53 selected candidates within the blastema was investigated by in situ hybridization. In summary, we identified a set of genes that are expressed specifically during regeneration and are therefore, likely candidates for the regulation of blastema formation. PMID:23658691

Anti-gravity treadmill can promote aerobic exercise for lower limb osteoarthritis patients.

PubMed

Kawae, Toshihiro; Mikami, Yukio; Fukuhara, Kouki; Kimura, Hiroaki; Adachi, Nobuo

2017-08-01

[Purpose] The anti-gravity treadmill (Alter-G ® ) allows the load on the lower limbs to be adjusted, which is considered useful for patients with lower limb osteoarthritis. The aim of the present study was to examine the effects of aerobic exercise using an anti-gravity treadmill in patients with lower limb osteoarthritis by using a cardiopulmonary exercise load monitoring system. [Subjects and Methods] The subjects were 20 patients with lower limb osteoarthritis. These subjects walked naturally for 8 minutes and then walked on the Alter-G for 8 minutes at their fastest speed at a load where lower limb pain was alleviated. [Results] Subjective and objective exercise intensity did not differ significantly between level ground walking and Alter-G walking neither before nor after walking. Pain before walking did not differ significantly between level ground walking and Alter-G walking, but pain after walking was significantly greater with level ground walking than with Alter-G walking. [Conclusion] Exercise therapy using an anti-gravity treadmill was useful for patients with lower limb osteoarthritis in terms of cardiopulmonary function, which suggested that this could become a new form of exercise therapy.

Limb-use by foraging marine turtles, an evolutionary perspective.

PubMed

Fujii, Jessica A; McLeish, Don; Brooks, Andrew J; Gaskell, John; Van Houtan, Kyle S

2018-01-01

The use of limbs for foraging is documented in both marine and terrestrial tetrapods. These behaviors were once believed to be less likely in marine tetrapods due to the physical constraints of body plans adapted to locomotion in a fluid environment. Despite these obstacles, ten distinct types of limb-use while foraging have been previously reported in nine marine tetrapod families. Here, we expand the types of limb-use documented in marine turtles and put it in context with the diversity of marine tetrapods currently known to use limbs for foraging. Additionally, we suggest that such behaviors could have occurred in ancestral turtles, and thus, possibly extend the evolutionary timeline of limb-use behavior in marine tetrapods back approximately 70 million years. Through direct observation in situ and crowd-sourcing, we document the range of behaviors across habitats and prey types, suggesting its widespread occurrence. We argue the presence of these behaviors among marine tetrapods may be limited by limb mobility and evolutionary history, rather than foraging ecology or social learning. These behaviors may also be remnant of ancestral forelimb-use that have been maintained due to a semi-aquatic life history.

Gender-related differences in lower limb alignment, range of joint motion, and the incidence of sports injuries in Japanese university athletes.

PubMed

Mitani, Yasuhiro

2017-01-01

[Purpose] To investigate the gender-related differences in lower limb alignment, range of joint motion, and history of lower limb sports injuries in Japanese university athletes. [Subjects and Methods] The subjects were 224 Japanese university athletes (154 males and 70 females). The quadriceps angle (Q-angle), arch height index, and ranges of internal and external rotation of the hip joints were measured. History of lower limb sports injury was surveyed using a questionnaire. [Results] Females had a significantly higher Q-angle and hip joint internal rotation angle and a significantly lower arch height index than males. The survey revealed that a significantly higher proportion of females had a history of lower limb sports injuries, and that the proportion of those with a history of foot/ankle injuries was particularly high. [Conclusion] These results suggested that females experience more lower limb sports injuries than males, and that a large proportion of these injuries involve the foot/ankle. Reduced lower limb alignment and increased range of joint motion in females may be risk factors for injury because they lead to increased physical stress being exerted on the lower legs during sporting activities.

Major lower extremity lawn mower injuries in children.

PubMed

Dormans, J P; Azzoni, M; Davidson, R S; Drummond, D S

1995-01-01

Between 1983 and 1993, 16 children with 18 lower extremity power lawn mower-related injuries were treated at Children's Hospital of Philadelphia. Eleven of 16 patients (69%) were bystanders or nonoperators. The average age at injury was 4 years 9 months. Length of follow-up averaged 3 years 10 months. There was an average of 4.9 procedures per patient. Fourteen of the 18 limbs injured required eventual amputation (78%). We propose a new classification of lawn mower injuries in children. The most common injury (16 of 18 limbs) was a shredding type injury and was either intercalary or distal. The second was a paucilaceration type (two of 18 limbs). Of the four salvaged limbs, there were two shredding type injuries, and on most recent follow-up are considered to have poor results. The two patients with the paucilaceration type injuries and limb salvage are considered to have excellent results. All patients with a shredding type injury ultimately required amputation or had poor results with the salvaged limb. Limb salvage surgery was associated with prolonged hospitalizations, a higher incidence of surgical problems, a longer treatment course, and more complications than early ablative procedures.

Motor control and learning with lower-limb myoelectric control in amputees.

PubMed

Alcaide-Aguirre, Ramses E; Morgenroth, David C; Ferris, Daniel P

2013-01-01

Advances in robotic technology have recently enabled the development of powered lower-limb prosthetic limbs. A major hurdle in developing commercially successful powered prostheses is the control interface. Myoelectric signals are one way for prosthetic users to provide feedforward volitional control of prosthesis mechanics. The goal of this study was to assess motor learning in people with lower-limb amputation using proportional myoelectric control from residual-limb muscles. We examined individuals with transtibial amputation and nondisabled controls performing tracking tasks of a virtual object. We assessed how quickly the individuals with amputation improved their performance and whether years since amputation correlated with performance. At the beginning of training, subjects with amputation performed much worse than control subjects. By the end of a short training period, tracking error did not significantly differ between subjects with amputation and nondisabled subjects. Initial but not final performance correlated significantly with time since amputation. This study demonstrates that although subjects with amputation may initially have poor volitional control of their residual lower-limb muscles, training can substantially improve their volitional control. These findings are encouraging for the future use of proportional myoelectric control of powered lower-limb prostheses.

Effects of postural changes of the upper limb on reflex transmission in the lower limb. Cervicolumbar reflex interactions in man.

PubMed

Delwaide, P J; Figiel, C; Richelle, C

1977-06-01

The influence of passive changes in upper limb position on the excitability of three myotatic arc reflexes (soleus, quadriceps, and biceps femoris) of the lower limb has been explored on 42 volunteers. The results indicate that the excitability of the three myotatic arcs can be influenced at a distance by postural modifications of the upper limb. When the ipsilateral upper limb is forwards or the contralateral backwards, a facilitation of both soleus and quadriceps tendon reflexes is observed while the biceps femoris reflexes are reduced. This pattern of facilitation and inhibition is reversed when the ipsilateral upper limb is backwards or the contralateral forwards. The facilitations as well as inhibitions of proximal myotatic arc reflexes are quantitatively more marked than that of the soleus reflex. Facilitation and inhibition are not linearly related to the angle of the arm with the trunk. Effects begin at a considerable angle, become maximal at 45 degrees, and progressively disappear for greater values. It is suggested that the distinct pattern of facilitation and inhibition which is exerted in reciprocal fashion on extensor and flexor motor nuclei might depend on the long propriospinal neurones connecting cervical and lumbar enlargements.

EFFECTS OF RETINOIC ACID AND ULTRAVIOLET RADIATION ON LIMB DEVELOPMENT IN ANURANS

EPA Science Inventory

Several recent studies suggest that the prevalence of limb abnormalities in North American anurans is elevated compared to historical records. These obsrvations have caused concern that environmental conditions are responsible for the increase through perturbation of normal limb ...

Recanalisation of Chronically Occluded Remote Superficial Femoral Artery Endarterectomy Through Angioplasty for Limb Salvage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Husainy, Mohammad Ali, E-mail: m.husainy@nhs.net; Slim, Hani; Rashid, Hisham

2017-02-15

We report a novel application of balloon angioplasty to recanalise a chronically occluded remote endarterectomy superficial femoral artery. This patient previously had two occluded surgical bypass grafts in an attempt to revascularise the limb and presented with critical limb ischaemia and necrotic foot ulcerations. Following the angioplasty, the patient showed significant improvement in rest pain and healing of the ulcerations. This technique may be useful for limb salvage in patients where surgical options have been exhausted.

Management of Major Limb Injuries

PubMed Central

Langer, Vijay

2014-01-01

Management of major limb injuries is a daunting challenge, especially as many of these patients have severe associated injuries. In trying to save life, often the limb is sacrificed. The existing guidelines on managing such trauma are often confusing. There is scope to lay down such protocols along with the need for urgent transfer of such patients to a multispecialty center equipped to salvage life and limb for maximizing outcome. This review article comprehensively deals with the issue of managing such major injuries. PMID:24511296

Achondroplasia: Really rhizomelic?

PubMed

Shelmerdine, Susan Cheng; Brittain, Helen; Arthurs, Owen J; Calder, Alistair D

2016-08-01

Achondroplasia is the most common form of short limb dwarfism in humans. The shortening of the limb lengths in achondroplasia is widely described as "rhizomelic." While this appearance may be convincing clinically, the description is not necessarily true or helpful radiologically. The aims of this study, were therefore, to determine whether rhizomelic shortening is a true feature of achondroplasia at diagnosis in infancy. Humeral, radial, femoral, and tibial diaphyseal lengths were recorded by two independent observers from 22 skeletal surveys of infants with achondroplasia and compared with 150 normal age-matched control subjects. Upper and lower limb bone length ratios (radial/humeral and tibial/femoral lengths, respectively) in both groups were compared using an unpaired t-test. Mean upper limb length ratios were statistically higher within the achondroplasia group at 0.87 ± 0.04 (n = 22, mean age 70 ± 94 days) compared to normal controls at 0.79 ± 0.02 (n = 150, mean age 113 days ± 88 days; P < 0.0001). Lower limb length ratios were not significantly different between groups (0.84 ± 0.04 vs. 0.83 ± 0.02, P = 0.46). There was good inter-observer agreement of limb length measurements, with an average measurement difference of 0.1 ± 1.4 mm. In conclusion, infants with achondroplasia demonstrate statistically significant rhizomelic shortening within the upper limbs, but not lower limbs at diagnosis, compared to normal controls. The term "rhizomelic shortening" in relation to achondroplasia should be reserved when describing upper limb proportions. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Risk factors for adverse outcomes after endovascular therapy for critical limb ischemia with tissue loss due to infrainguinal artery disease.

PubMed

Tnishibe, Toshiya; Yamamoto, Kiyohito; Toguchi, Kayo; Seike, Yoshimasa; Ito, Naoki; Nishibe, Masayasu; Koizumi, Jun; Dardik, Alan; Ogino, Hitoshi

2016-10-01

The purpose of this study was to analyze the risk factors for an adverse outcome after endovascular therapy (EVT) for critical limb ischemia (CLI) with tissue loss due to infrainguinal artery disease. We retrospectively reviewed the charts of patients with tissue loss (Rutherford class 5 and 6) due to infrainguinal artery disease who were managed with endovascular therapy (EVT) between January 2006 and December 2013. The primary endpoint was amputation-free survival (AFS), while the secondary endpoints were freedom from a major adverse limb event (MALE) plus perioperative (30 days) death (POD), limb salvage, and survival rates at one year. Multivariable perioperative predictors of AFS were identified using the stepwise Cox proportional hazards regression model. A total of 65 patients underwent EVT for infrainguinal artery disease on 72 limbs. The technical success rate was 94% (68/72), while the clinical success was attained in 54 of 72 limbs (72%). The AFS, MALE + POD, limb salvage, and survival rates at one year were 76%, 86%, 91%, and 81%, respectively. The multivariate analysis demonstrated that major tissue loss classified as Rutherford class 6 (HR, 5.68; 95% CI, 2.29-14.13; P<0.05) was negatively associated with decreased AFS, while clinical success (HR, 0.25; 95% CI, 0.11-0.60; P<0.05) was positively associated with increased AFS. EVT resulted in an acceptable rate of AFS, MALE+POD, limb salvage, and survival. However, we must keep in mind that there are significant limitations to be considered for EVT in patients with major tissue loss, and that, even if revascularization could be successfully performed, a significant number of the treated limbs are still in a critical situation, such as major amputation or death.

Force-velocity properties' contribution to bilateral deficit during ballistic push-off.

PubMed

Samozino, Pierre; Rejc, Enrico; di Prampero, Pietro Enrico; Belli, Alain; Morin, Jean-Benoît

2014-01-01

The objective of this study is to quantify the contribution of the force-velocity (F-v) properties to bilateral force deficit (BLD) in ballistic lower limb push-off and to relate it to individual F-v mechanical properties of the lower limbs. The F-v relation was individually assessed from mechanical measurements for 14 subjects during maximal ballistic lower limb push-offs; its contribution to BLD was then investigated using a theoretical macroscopic approach, considering both the mechanical constraints of movement dynamics and the maximal external capabilities of the lower limb neuromuscular system. During ballistic lower limb push-off, the maximum force each lower limb can produce was lower during bilateral than unilateral actions, thus leading to a BLD of 36.7% ± 5.7%. The decrease in force due to the F-v mechanical properties amounted to 19.9% ± 3.6% of the force developed during BL push-offs, which represents a nonneural contribution to BLD of 43.5% ± 9.1%. This contribution to BLD that cannot be attributed to changes in neural features was negatively correlated to the maximum unloaded extension velocity of the lower limb (r = -0.977, P < 0.001). During ballistic lower limb push-off, BLD is due to both neural alterations and F-v mechanical properties, the latter being associated with the change in movement velocity between bilateral and unilateral actions. The level of the contribution of the F-v properties depends on the individual F-v mechanical profile of the entire lower limb neuromuscular system: the more the F-v profile is oriented toward velocity capabilities, the lower the loss of force from unilateral to bilateral push-offs due to changes in movement velocity.

Hip Strength in Patients with Quadriceps Strength Deficits after ACL Reconstruction.

PubMed

Bell, David R; Trigsted, Stephanie M; Post, Eric G; Walden, Courtney E

2016-10-01

Quadriceps strength deficits persist for years after anterior cruciate ligament (ACL) reconstruction, and patients with these deficits often shift torque demands away from the knee extensors to the hip during functional tasks. However, it is not clear how quadriceps strength deficits may affect hip strength. Therefore, the purpose of this study was to investigate differences in lower extremity strength in individuals with ACL reconstruction with differing levels of quadriceps strength asymmetry. Isometric strength was recorded bilaterally in 135 participants (73 control and 62 with unilateral ACL reconstruction, time from surgery = 30.9 ± 17.6 months) from the knee extensors and flexors, hip extensors and abductors, and hip internal and external rotator muscle groups. Symmetry indices (limb symmetry index (LSI)) were created based on quadriceps strength, and subjects with ACL reconstruction were subdivided (high quadriceps (LSI ≥ 90%), n = 37; low quadriceps (LSI < 85%), n = 18). Individual group (control vs high quadriceps vs low quadriceps) by limb (reconstructed/nondominant vs healthy/dominant) repeated-measures ANOVA was used to compare strength (%BW) for each of the six joint motions of interest (knee extensors/flexors, hip abductors/extensors/external, and internal rotators) while controlling for time from surgery. An interaction was observed for quadriceps strength (P < 0.001), and the reconstructed limb in the low quadriceps group was weaker than all other limbs. A main effect for group was observed with the low quadriceps group having greater hip extension (P = 0.007) strength in both limbs compared with the other groups. Knee flexion strength was weaker in the reconstructed limb of the high quadriceps group (P = 0.047) compared with all other groups and limbs. Individuals with ACL reconstruction and involved limb quadriceps weakness have greater hip extension strength in both limbs compared with patients with bilateral strength symmetry and controls.

Extrinsic Factors as Component Positions to Bone and Intrinsic Factors Affecting Postoperative Rotational Limb Alignment in Total Knee Arthroplasty.

PubMed

Mochizuki, Tomoharu; Sato, Takashi; Tanifuji, Osamu; Watanabe, Satoshi; Kobayashi, Koichi; Endo, Naoto

2018-02-13

This study aimed to identify the factors affecting postoperative rotational limb alignment of the tibia relative to the femur. We hypothesized that not only component positions but also several intrinsic factors were associated with postoperative rotational limb alignment. This study included 99 knees (90 women and 9 men) with a mean age of 77 ± 6 years. A three-dimensional (3D) assessment system was applied under weight-bearing conditions to biplanar long-leg radiographs using 3D-to-2D image registration technique. The evaluation parameters were (1) component position; (2) preoperative and postoperative coronal, sagittal, and rotational limb alignment; (3) preoperative bony deformity, including femoral torsion, condylar twist angle, and tibial torsion; and (4) preoperative and postoperative range of motion (ROM). In multiple linear regression analysis using a stepwise procedure, postoperative rotational limb alignment was associated with the following: (1) rotation of the component position (tibia: β = 0.371, P < .0001; femur: β = -0.327, P < .0001), (2) preoperative rotational limb alignment (β = 0.253, P = .001), (3) postoperative flexion angle (β = 0.195, P = .007), and (4) tibial torsion (β = 0.193, P = .010). In addition to component positions, the intrinsic factors, such as preoperative rotational limb alignment, ROM, and tibial torsion, affected postoperative rotational limb alignment. On a premise of correct component positions, the intrinsic factors that can be controlled by surgeons should be taken care. In particular, ROM is necessary to be improved within the possible range to acquire better postoperative rotational limb alignment. Copyright © 2018 Elsevier Inc. All rights reserved.

Modulation of phase durations, phase variations, and temporal coordination of the four limbs during quadrupedal split-belt locomotion in intact adult cats

PubMed Central

D'Angelo, Giuseppe; Thibaudier, Yann; Telonio, Alessandro; Hurteau, Marie-France; Kuczynski, Victoria; Dambreville, Charline

2014-01-01

Stepping along curvilinear paths produces speed differences between the inner and outer limb(s). This can be reproduced experimentally by independently controlling left and right speeds with split-belt locomotion. Here we provide additional details on the pattern of the four limbs during quadrupedal split-belt locomotion in intact cats. Six cats performed tied-belt locomotion (same speed bilaterally) and split-belt locomotion where one side (constant side) stepped at constant treadmill speed while the other side (varying side) stepped at several speeds. Cycle, stance, and swing durations changed in parallel in homolateral limbs with shorter and longer stance and swing durations on the fast side, respectively, compared with the slow side. Phase variations were quantified in all four limbs by measuring the slopes of the regressions between stance and cycle durations (rSTA) and between swing and cycle durations (rSW). For a given limb, rSTA and rSW were not significantly different from one another on the constant side whereas on the varying side rSTA increased relative to tied-belt locomotion while rSW became more negative. Phase variations were similar for homolateral limbs. Increasing left-right speed differences produced a large increase in homolateral double support on the slow side, while triple-support periods decreased. Increasing left-right speed differences altered homologous coupling, homolateral coupling on the fast side, and coupling between the fast hindlimb and slow forelimb. Results indicate that homolateral limbs share similar control strategies, only certain features of the interlimb pattern adjust, and spinal locomotor networks of the left and right sides are organized symmetrically. PMID:25031257

A difference in systolic blood pressure between arms and between lower limbs is a novel risk marker for diabetic nephropathy in patients with type 2 diabetes.

PubMed

Okada, Hiroshi; Fukui, Michiaki; Tanaka, Muhei; Matsumoto, Shinobu; Mineoka, Yusuke; Nakanishi, Naoko; Asano, Mai; Yamazaki, Masahiro; Hasegawa, Goji; Nakamura, Naoto

2013-05-01

Recent studies have demonstrated that a difference in systolic blood pressure (SBP) between arms is associated with both vascular disease and mortality. The aim of this study was to investigate the relationship between a difference in SBP between arms and between lower limbs and the degree of albuminuria, which is an established marker for cardiovascular disease and diabetic nephropathy in patients with Type 2 diabetes. We measured blood pressure in the arms and lower limbs of 314 consecutive patients with Type 2 diabetes, and we calculated a difference in SBP between arms and between lower limbs. We then evaluated the relationship of the difference in SBP between arms and between lower limbs to the degree of urinary albumin excretion (UAE). The average difference in SBP between arms and between lower limbs was 3.52±3.94 and 9.66±14.1 mm Hg, respectively. Multiple regression analyses demonstrated that a difference in SBP between arms (β=0.172, P=0.0239) and between lower limbs (β=0.238, P=0.0033) independently correlated with the logarithm of the UAE. Multiple logistic regression analyses showed that a difference in SBP of 10 mm Hg between arms (odds ratio 12.23 (95% CI 1.130-132.35), P<0.0393) and a difference in SBP of 15 mm Hg between lower limbs (odds ratio 4.291 (95% CI 1.403-13.123), P<0.0106) correlated with the risk of albuminuria. A difference in SBP between arms and between lower limbs, therefore, could be a novel risk marker for diabetic nephropathy in patients with Type 2 diabetes.

The Organization and Control of Intra-Limb Anticipatory Postural Adjustments and Their Role in Movement Performance

PubMed Central

Cavallari, Paolo; Bolzoni, Francesco; Bruttini, Carlo; Esposti, Roberto

2016-01-01

Anticipatory Postural Adjustments (APAs) are commonly described as unconscious muscular activities aimed to counterbalance the perturbation caused by the primary movement, so as to ensure the whole-body balance, as well as contributing to initiate the displacement of the body center of mass when starting gait or whole-body reaching movements. These activities usually create one or more fixation chains which spread over several muscles of different limbs, and may be thus called inter-limb APAs. However, it has been reported that APAs also precede voluntary movements involving tiny masses, like a flexion/extension of the wrist or even a brisk flexion of the index-finger. In particular, such movements are preceded by an intra-limb APA chain, that involves muscles acting on the proximal joints. Considering the small mass of the moving segments, it is unlikely that the ensuing perturbation could threaten the whole-body balance, so that it is interesting to enquire the physiological role of intra-limb APAs and their organization and control compared to inter-limb APAs. This review is focused on intra-limb APAs and highlights a strict correspondence in their behavior and temporal/spatial organization with respect to inter-limb APAs. Hence it is suggested that both are manifestations of the same phenomenon. Particular emphasis is given to intra-limb APAs preceding index-finger flexion, because their relatively simple biomechanics and the fact that muscular actions were limited to a single arm allowed peculiar investigations, leading to important conclusions. Indeed, such paradigm provided evidence that by granting a proper fixation of those body segments proximal to the moving one APAs are involved in refining movement precision, and also that APAs and prime mover activation are driven by a shared motor command. PMID:27807411

Isolated limb perfusion for the management limb threatening soft tissue sarcomas: The role of histological type on clinical outcomes.

PubMed

Rastrelli, M; Mocellin, S; Stramare, R; Brunello, A; Maruzzo, M; Basso, U; Scarzello, G; Buzzaccarini, M S; Pilati, P; Saadeh, L M; Del Fiore, S P; Tosi, A; Montesco, C; Campana, L G; Tropea, S; Rossi, C R

2017-02-01

Hyperthermic isolated limb perfusion (HILP) is an effective neoadjuvant treatment to avoid amputation in patients with locally advanced extremity soft tissue sarcomas (STS). We aimed to investigate whether STS histological type plays a role in predicting clinical outcomes. This study reports a retrospective analysis of 125 patients with limb threatening STS (liposarcoma, n = 41; malignant peripheral nerve sheath tumor, n = 20; leiomyosarcoma, n = 20; miscellany, n = 44), who underwent HILP from 1990 through 2015 at our institution. The following endpoints were evaluated: tumor response (assessed by radiological imaging and histology), limb sparing rate, local progression-free survival (LPFS) and overall survival (OS). On average, overall (complete + partial) tumor response was significantly greater in patients affected with liposarcoma as compared to those with other histotypes (radiological response rate: 38/41, 92.7% vs 66/84, 78.6%, P-value: 0.048; mean histological necrosis: 83.6% vs 52.9%, P < 0.0001). Limb sparing rate was also higher among patients with liposarcoma as compared to other histotypes (39/41, 95.1% vs 62/84, 73.8%, P-value: 0.005). As regards survival, LPFS was similar across tumor types, whereas OS resulted significantly worse in patients with limb leiomyosarcoma (log-rank P-value: 0.009). HILP is a very effective treatment modality for limb threatening STS. In our series, liposarcoma appears to be the histological type most sensitive to HILP in terms of tumor response and thus limb sparing, which might help clinicians in the patient selection process. Copyright © 2016 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

Conditional inactivation of Has2 reveals a crucial role for hyaluronan in skeletal growth, patterning, chondrocyte maturation and joint formation in the developing limb

PubMed Central

Matsumoto, Kazu; Li, Yingcui; Jakuba, Caroline; Sugiyama, Yoshinori; Sayo, Tetsuya; Okuno, Misako; Dealy, Caroline N.; Toole, Bryan P.; Takeda, Junji; Yamaguchi, Yu; Kosher, Robert A.

2009-01-01

Summary The glycosaminoglycan hyaluronan (HA) is a structural component of extracellular matrices and also interacts with cell surface receptors to directly influence cell behavior. To explore functions of HA in limb skeletal development, we conditionally inactivated the gene for HA synthase 2, Has2, in limb bud mesoderm using mice that harbor a floxed allele of Has2 and mice carrying a limb mesoderm-specific Prx1-Cre transgene. The skeletal elements of Has2-deficient limbs are severely shortened, indicating that HA is essential for normal longitudinal growth of all limb skeletal elements. Proximal phalanges are duplicated in Has2 mutant limbs indicating an involvement of HA in patterning specific portions of the digits. The growth plates of Has2-deficient skeletal elements are severely abnormal and disorganized, with a decrease in the deposition of aggrecan in the matrix and a disruption in normal columnar cellular relationships. Furthermore, there is a striking reduction in the number of hypertrophic chondrocytes and in the expression domains of markers of hypertrophic differentiation in the mutant growth plates, indicating that HA is necessary for the normal progression of chondrocyte maturation. In addition, secondary ossification centers do not form in the central regions of Has2 mutant growth plates owing to a failure of hypertrophic differentiation. In addition to skeletal defects, the formation of synovial joint cavities is defective in Has2-deficient limbs. Taken together, our results demonstrate that HA has a crucial role in skeletal growth, patterning, chondrocyte maturation and synovial joint formation in the developing limb. PMID:19633173

Gadolinium and ruthenium red attenuate remote hind limb preconditioning-induced cardioprotection: possible role of TRP and especially TRPV channels.

PubMed

Randhawa, Puneet Kaur; Jaggi, Amteshwar Singh

2016-08-01

Remote ischemic preconditioning is a well reported therapeutic strategy that induces cardioprotective effects but the underlying intracellular mechanisms have not been widely explored. The current study was designed to investigate the involvement of TRP and especially TRPV channels in remote hind limb preconditioning-induced cardioprotection. Remote hind limb preconditioning stimulus (4 alternate cycles of inflation and deflation of 5 min each) was delivered using a blood pressure cuff tied on the hind limb of the anesthetized rat. Using Langendorff's system, the heart was perfused and subjected to 30-min ischemia and 120-min reperfusion. The myocardial injury was assessed by measuring infarct size, lactate dehydrogenase (LDH), creatine kinase (CK), LVDP, +dp/dtmax, -dp/dtmin, heart rate, and coronary flow rate. Gadolinium, TRP blocker, and ruthenium red, TRPV channel blocker, were employed as pharmacological tools. Remote hind limb preconditioning significantly reduced the infarct size, LDH release, CK release and improved coronary flow rate, hemodynamic parameters including LVDP, +dp/dtmax, -dp/dtmin, and heart rate. However, gadolinium (7.5 and 15 mg kg(-1)) and ruthenium red (4 and 8 mg kg(-1)) significantly attenuated the cardioprotective effects suggesting the involvement of TRP especially TRPV channels in mediating remote hind limb preconditioning-induced cardioprotection. Remote hind limb preconditioning stimulus possibly activates TRPV channels on the heart or sensory nerve fibers innervating the heart to induce cardioprotective effects. Alternatively, remote hind limb preconditioning stimulus may also activate the mechanosensitive TRP and especially TRPV channels on the sensory nerve fibers innervating the skeletal muscles to trigger cardioprotective neurogenic signaling cascade. The cardioprotective effects of remote hind limb preconditioning may be mediated via activation of mechanosensitive TRP and especially TRPV channels.

Evaluating optimal superficial limb perfusion at different angles using non-invasive micro-lightguide spectrophotometry.

PubMed

Darmanin, Geraldine; Jaggard, Matthew; Hettiaratchy, Shehan; Nanchahal, Jagdeep; Jain, Abhilash

2013-06-01

It is common practice to elevate the limbs postoperatively to reduce oedema and hence optimise perfusion and facilitate rehabilitation. However, elevation may be counterproductive as it reduces the mean perfusion pressure. There are no clear data on the optimal position of the limbs even in normal subjects. The optimal position of limbs was investigated in 25 healthy subjects using a non-invasive micro-lightguide spectrophotometry system "O2C", which indirectly measures skin and superficial tissue perfusion through blood flow, oxygen saturation and relative haemoglobin concentration. We found a reduction in skin and superficial tissue blood flow of 17% (p=0.0001) on arm elevation (180° shoulder flexion) as compared to heart level and an increase in skin and superficial tissue blood flow of 25% (p=0.02) on forearm elevation of 45°. Lower limb skin and superficial tissue blood flow decreased by 15% (p=0.004) on elevation to 47 cm and by 70% on dependency (p=0.0001) compared to heart level. However, on elevation of the lower limb there was also a 28% reduction in superficial venous pooling (p=0.0001) compared to heart level. In the normal limb, the position for optimal superficial perfusion of the upper limb is with the arm placed at heart level and forearm at 45°. In the lower limb the optimal position for superficial perfusion would be at heart level. However, some degree of elevation may be useful if there is an element of venous congestion. Copyright © 2013 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Evidence for existence of trunk-limb neural interaction in the corticospinal pathway.

PubMed

Sasaki, Atsushi; Milosevic, Matija; Sekiguchi, Hirofumi; Nakazawa, Kimitaka

2018-03-06

In humans, trunk muscles have an essential role in postural control as well as walking. However, little is known about the mechanisms of interaction with different muscles, especially related to how trunk muscles interact with the limbs. Contraction of muscles can modulate the corticospinal excitability not only of the contracted muscle, but also of other muscles even in the remote segments of the body. However, "remote effect" mechanism has only been examined for inter-limb interactions. The aim of our current study was to test if there are trunk-limb interactions in the corticospinal pathways. We examined corticospinal excitability of: (a) trunk muscles at rest when hands, legs and jaw muscles were contracted and; (b) hand, leg, and jaw muscles at rest when trunk muscles were contracted. We measured motor evoked potentials elicited using transcranial magnetic stimulation in the rectus abdominis, flexor digitorum superficialis, masseter, tibialis anterior muscles under the following experimental conditions: (1) participants remained relaxed (Rest); (2) during trunk contraction (Trunk); (3) during bilateral hand clenching (Hands); (4) during jaw clenching (Jaw); and (5) during bilateral ankle dorsiflexion (Legs). Each condition was performed at three different stimulation intensities and conditions were randomized between participants. We found that voluntary contraction of trunk muscle facilitated the corticospinal excitability of upper-limb and lower-limb muscles during rest state. Furthermore, voluntary contraction of upper-limb muscle also facilitated the corticospinal excitability of trunk muscles during rest state. Overall, these results suggest the existence of trunk-limb interaction in the corticospinal pathway, which is likely depended on proximity of the trunk and limb representation in the motor cortex. Copyright © 2018 Elsevier B.V. All rights reserved.

Resveratrol increases nitric oxide production in the rat thick ascending limb via Ca2+/calmodulin.

PubMed

Gonzalez-Vicente, Agustin; Cabral, Pablo D; Garvin, Jeffrey L

2014-01-01

The thick ascending limb of the loop of Henle reabsorbs 30% of the NaCl filtered through the glomerulus. Nitric oxide (NO) produced by NO synthase 3 (NOS3) inhibits NaCl absorption by this segment. Resveratrol, a polyphenol, has beneficial cardiovascular and renal effects, many of which are mediated by NO. Resveratrol increases intracellular Ca2+ (Cai) and AMP kinase (AMPK) and NAD-dependent deacetylase sirtuin1 (SIRT1) activities, all of which could activate NO production. We hypothesized that resveratrol stimulates NO production by thick ascending limbs via a Ca2+/calmodulin-dependent mechanism. To test this, the effect of resveratrol on NO bioavailability was measured in thick ascending limb suspensions. Cai was measured in single perfused thick ascending limbs. SIRT1 activity and expression were measured in thick ascending limb lysates. Resveratrol (100 µM) increased NO bioavailability in thick ascending limb suspensions by 1.3±0.2 AFU/mg/min (p<0.03). The NOS inhibitor L-NAME blunted resveratrol-stimulated NO bioavailability by 96±11% (p<0.03). The superoxide scavenger tempol had no effect. Resveratrol elevated Cai from 48±7 to 135±24 nM (p<0.01) in single tubules. In Ca2+-free media, the resveratrol-induced increase in NO was blunted by 60±20% (p<0.05) and the rise in Cai reduced by 80%. Calmodulin inhibition prevented the resveratrol-induced increase in NO (p<0.002). AMPK inhibition had no effect. Resveratrol did not increase SIRT1 activity. We conclude that resveratrol increases NO production in thick ascending limbs via a Ca2+/calmodulin dependent mechanism, and SIRT1 and AMPK do not participate. Resveratrol-stimulated NO production in thick ascending limbs may account for part of its beneficial effects.

The impact of workplace risk factors on the occurrence of neck and upper limb pain: a general population study.

PubMed

Sim, Julius; Lacey, Rosie J; Lewis, Martyn

2006-09-19

Work-related neck and upper limb pain has mainly been studied in specific occupational groups, and little is known about its impact in the general population. The objectives of this study were to estimate the prevalence and population impact of work-related neck and upper limb pain. A cross-sectional survey was conducted of 10,000 adults in North Staffordshire, UK, in which there is a common local manual industry. The primary outcome measure was presence or absence of neck and upper limb pain. Participants were asked to give details of up to five recent jobs, and to report exposure to six work activities involving the neck or upper limbs. Psychosocial measures included job control, demand and support. Odds ratios (ORs) and population attributable fractions were calculated for these risk factors. The age-standardized one-month period prevalence of neck and upper limb pain was 44%. There were significant independent associations between neck and upper limb pain and: repeated lifting of heavy objects (OR = 1.4); prolonged bending of neck (OR = 2.0); working with arms at/above shoulder height (OR = 1.3); little job control (OR = 1.6); and little supervisor support (OR = 1.3). The population attributable fractions were 0.24 (24%) for exposure to work activities and 0.12 (12%) for exposure to psychosocial factors. Neck and upper limb pain is associated with both physical and psychosocial factors in the work environment. Inferences of cause-and-effect from cross-sectional studies must be made with caution; nonetheless, our findings suggest that modification of the work environment might prevent up to one in three of cases of neck and upper limb pain in the general population, depending on current exposures to occupational risk.

Outcomes of lower extremity bypass performed for acute limb ischemia

PubMed Central

Baril, Donald T.; Patel, Virendra I.; Judelson, Dejah R.; Goodney, Philip P.; McPhee, James T.; Hevelone, Nathanael D.; Cronenwett, Jack L.; Schanzer, Andres

2013-01-01

Objective Acute limb ischemia remains one of the most challenging emergencies in vascular surgery. Historically, outcomes following interventions for acute limb ischemia have been associated with high rates of morbidity and mortality. The purpose of this study was to determine contemporary outcomes following lower extremity bypass performed for acute limb ischemia. Methods All patients undergoing infrainguinal lower extremity bypass between 2003 and 2011 within hospitals comprising the Vascular Study Group of New England were identified. Patients were stratified according to whether or not the indication for lower extremity bypass was acute limb ischemia. Primary end points included bypass graft occlusion, major amputation, and mortality at 1 year postoperatively as determined by Kaplan-Meier life table analysis. Multivariable Cox proportional hazards models were constructed to evaluate independent predictors of mortality and major amputation at 1 year. Results Of 5712 lower extremity bypass procedures, 323 (5.7%) were performed for acute limb ischemia. Patients undergoing lower extremity bypass for acute limb ischemia were similar in age (66 vs 67; P = .084) and sex (68% male vs 69% male; P = .617) compared with chronic ischemia patients, but were less likely to be on aspirin (63% vs 75%; P < .0001) or a statin (55% vs 68%; P < .0001). Patients with acute limb ischemia were more likely to be current smokers (49% vs 39%; P < .0001), to have had a prior ipsilateral bypass (33% vs 24%; P = .004) or a prior ipsilateral percutaneous intervention (41% vs 29%; P = .001). Bypasses performed for acute limb ischemia were longer in duration (270 vs 244 minutes; P = .007), had greater blood loss (363 vs 272 mL; P < .0001), and more commonly utilized prosthetic conduits (41% vs 33%; P = .003). Acute limb ischemia patients experienced increased in-hospital major adverse events (20% vs 12%; P < .0001) including myocardial infarction, congestive heart failure exacerbation, deterioration in renal function, and respiratory complications. Patients who underwent lower extremity bypass for acute limb ischemia had no difference in rates of graft occlusion (18.1% vs 18.5%; P = .77), but did have significantly higher rates of limb loss (22.4% vs 9.7%; P < .0001) and mortality (20.9% vs 13.1%; P < .0001) at 1 year. On multivariable analysis, acute limb ischemia was an independent predictor of both major amputation (hazard ratio, 2.16; confidence interval, 1.38–3.40; P = .001) and mortality (hazard ratio, 1.41; confidence interval, 1.09–1.83; P = .009) at 1 year. Conclusions Patients who present with acute limb ischemia represent a less medically optimized subgroup within the population of patients undergoing lower extremity bypass. These patients may be expected to have more complex operations followed by increased rates of perioperative adverse events. Additionally, despite equivalent graft patency rates, patients undergoing lower extremity bypass for acute ischemia have significantly higher rates of major amputation and mortality at 1 year. PMID:23714364

Outcomes of lower extremity bypass performed for acute limb ischemia.

PubMed

Baril, Donald T; Patel, Virendra I; Judelson, Dejah R; Goodney, Philip P; McPhee, James T; Hevelone, Nathanael D; Cronenwett, Jack L; Schanzer, Andres

2013-10-01

Acute limb ischemia remains one of the most challenging emergencies in vascular surgery. Historically, outcomes following interventions for acute limb ischemia have been associated with high rates of morbidity and mortality. The purpose of this study was to determine contemporary outcomes following lower extremity bypass performed for acute limb ischemia. All patients undergoing infrainguinal lower extremity bypass between 2003 and 2011 within hospitals comprising the Vascular Study Group of New England were identified. Patients were stratified according to whether or not the indication for lower extremity bypass was acute limb ischemia. Primary end points included bypass graft occlusion, major amputation, and mortality at 1 year postoperatively as determined by Kaplan-Meier life table analysis. Multivariable Cox proportional hazards models were constructed to evaluate independent predictors of mortality and major amputation at 1 year. Of 5712 lower extremity bypass procedures, 323 (5.7%) were performed for acute limb ischemia. Patients undergoing lower extremity bypass for acute limb ischemia were similar in age (66 vs 67; P = .084) and sex (68% male vs 69% male; P = .617) compared with chronic ischemia patients, but were less likely to be on aspirin (63% vs 75%; P < .0001) or a statin (55% vs 68%; P < .0001). Patients with acute limb ischemia were more likely to be current smokers (49% vs 39%; P < .0001), to have had a prior ipsilateral bypass (33% vs 24%; P = .004) or a prior ipsilateral percutaneous intervention (41% vs 29%; P = .001). Bypasses performed for acute limb ischemia were longer in duration (270 vs 244 minutes; P = .007), had greater blood loss (363 vs 272 mL; P < .0001), and more commonly utilized prosthetic conduits (41% vs 33%; P = .003). Acute limb ischemia patients experienced increased in-hospital major adverse events (20% vs 12%; P < .0001) including myocardial infarction, congestive heart failure exacerbation, deterioration in renal function, and respiratory complications. Patients who underwent lower extremity bypass for acute limb ischemia had no difference in rates of graft occlusion (18.1% vs 18.5%; P = .77), but did have significantly higher rates of limb loss (22.4% vs 9.7%; P < .0001) and mortality (20.9% vs 13.1%; P < .0001) at 1 year. On multivariable analysis, acute limb ischemia was an independent predictor of both major amputation (hazard ratio, 2.16; confidence interval, 1.38-3.40; P = .001) and mortality (hazard ratio, 1.41; confidence interval, 1.09-1.83; P = .009) at 1 year. Patients who present with acute limb ischemia represent a less medically optimized subgroup within the population of patients undergoing lower extremity bypass. These patients may be expected to have more complex operations followed by increased rates of perioperative adverse events. Additionally, despite equivalent graft patency rates, patients undergoing lower extremity bypass for acute ischemia have significantly higher rates of major amputation and mortality at 1 year. Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

[A Case of Middle Cerebral Artery Stenosis Presented with Limb-Shaking TIA].

PubMed

Uno, Junji; Mineta, Haruyuki; Ren, Nice; Takagishi, Sou; Nagaoka, Shintarou; Kameda, Katsuharu; Maeda, Kazushi; Ikai, Yoshiaki; Gi, Hidefuku

2016-07-01

Involuntary movement is a rare clinical manifestation of transient ischemic attack (TIA). However, limb-shaking TIA is well described presentation of carotid occlusive disease. We present the case of a patient who developed limb-shaking TIA associated with high-grade stenosis of middle cerebral artery (M1), which was treated with percutaneous transluminal angioplasty (PTA). The procedure was performed successfully without complication and the symptom disappeared immediately after the procedure. The patient remained free of symptoms at the 38-month follow-up. There was no tendency of restenosis of M1. In this case, PTA was technically feasible and beneficial for limb-shaking TIA with M1 stenosis. Limb-shaking TIA can be a symptom of high-grade stenosis of M1.

Temperature-salinity structure of the AMOC in high-resolution ocean simulations and in CMIP5 models

NASA Astrophysics Data System (ADS)

Wang, F.; Xu, X.; Chassignet, E.

2017-12-01

On average, the CMIP5 models represent the AMOC structure, water properties, Heat transport and Freshwater transport reasonably well. For temperature, CMIP5 models exhibit a colder northward upper limb and a warmer southward lower limb. the temperature contrast induces weaker heat transport than observation. For salinity, CMIP5 models exhibit saltier southward lower limb, thus contributes to weaker column freshwater transport. Models have large spread, among them, AMOC strength contributes to Heat transport but not freshwater transport. AMOC structure (the overturning depth) contributes to transport-weighted temperature not transport-weighted salinity in southward lower limb. The salinity contrast in upper and lower limb contributes to freshwater transport, but temperature contrast do not contribute to heat transport.

Concentrations and loads of cadmium, lead, and zinc measured on the ascending and descending limbs of the 1999 snowmelt-runoff hydrographs for nine water-quality stations, Coeur d'Alene River basin, Idaho

USGS Publications Warehouse

Woods, Paul F.

2001-01-01

Hysteresis effects on concentrations and loads over the ascending and descending limbs of the snowmelt-runoff hydrograph were quite apparent, especially for whole-water recoverable constituents. Hysteresis is present when a property, such as constituent concentration or load, has different values for a given discharge over the ascending and descending limbs of a hydrograph. During this study, loads of whole-water recoverable constituents on the ascending limb were between 1.5 and 3.6 times larger than those mea- sured on the descending limb at nearly equal discharge. In contrast, dissolved constituents showed minimal hysteresis effects.

Prevention of Kinked Stent Graft Limb Due to Severe Angulated Proximal Neck during Endovascular Repair for Abdominal Aortic Aneurysm.

PubMed

Oh, Pyung Chun; Kim, Minsu; Shin, Eak Kyun; Kang, Woong Chol

2018-04-20

Although the technology of endovascular aortic repair (EVAR) for abdominal aortic aneurysm (AAA) is evolving that make it appealing for challenging anatomy, proximal aortic neck morphology, especially severe angulation, is still one of the most determinants for a successful procedure. We describe a patient of AAA with severely angulated proximal neck, in whom kinked stent graft limb occurred against severe angulation of proximal neck. Then, we suggested how to prevent this complication in the second patient. Our case demonstrated the stent graft limb could be kinked by severe aortic neck angulation, making it challenging. However, the kinked stent graft limb could be prevented by deploying stent graft limbs below the most severely angulated aortic neck intentionally.

Hang Them High: A Hands-Free Technique for Upper Extremity Limb Holding During Surgical Preparation.

PubMed

Aneja, Arun; Leung, Patrick; Marquez-Lara, Alejandro

Lifting and holding upper and lower limbs during the "prep and drape" portion of certain orthopaedic procedures exert strong forces on the holder and may lead to musculoskeletal disorders. To address these challenges during upper extremity procedures, this article describes a hand-free elevation and traction technique of the upper limbs during preoperative skin preparation with the use of items readily available within the operating room (OR). This technique is particularly useful for heavy or fractured limbs that may impose a physical challenge to lift and maintain in a stable position. Implementation of this technique reduces the risk to nurses, OR personnel, and caregivers of developing work-related musculoskeletal injuries while lifting and holding limbs in the orthopaedic OR.

ENGINEERING APPLICATION AND ECONOMICS OF LIMB (LIMESTONE INJECTION/MULTISTAGE BURNERS)

EPA Science Inventory

The paper describes the use of an EPA LIMB cost model, in conjunction with cost and performance models for flue gas desulfurization (FGD), to compare these two technologies under similar premises. (NOTE: The performance goals of LIMB, EPA's acronym for Limestone Injection/Multist...

A cortical-spinal prosthesis for targeted limb movement in paralyzed primate avatars

PubMed Central

Shanechi, Maryam M.; Hu, Rollin C.; Williams, Ziv M.

2014-01-01

Motor paralysis is among the most disabling aspects of injury to the central nervous system. Here we develop and test a target-based cortical-spinal neural prosthesis that employs neural activity recorded from pre-motor neurons to control limb movements in functionally paralyzed primate avatars. Given the complexity by which muscle contractions are naturally controlled, we approach the problem of eliciting goal-directed limb movement in paralyzed animals by focusing on the intended targets of movement rather than their intermediate trajectories. We then match this information in real-time with spinal cord and muscle stimulation parameters that produce free planar limb movements to those intended target locations. We demonstrate that both the decoded activities of pre-motor populations and their adaptive responses can be used, after brief training, to effectively direct an avatar’s limb to distinct targets variably displayed on a screen. These findings advance the future possibility of reconstituting targeted limb movement in paralyzed subjects. PMID:24549394

Upper limb dysfunction following selective neck dissection: a retrospective questionnaire study.

PubMed

Carr, Simon D; Bowyer, Duncan; Cox, Graham

2009-06-01

To determine total upper limb function following selective neck dissection over a mean follow-up of 1.6 years. A retrospective questionnaire study in a tertiary head and neck surgical unit. One hundred forty-eight patients who underwent selective neck dissection for head and neck cancer from January 2000 to December 2005 were invited to participate. The main outcome measure was ipsilateral upper limb dysfunction as measured by the Disability of Arm, Shoulder and Hand (DASH) questionnaire. Sixty-five patients responded to the invitation to join the study from 148 invited. Despite accessory nerve conserving surgery for all the selective neck dissections studied, 23% reported no upper limb dysfunction, 54% reported mild upper limb dysfunction, 15% reported moderate, and 8% reported a severe dysfunction. Long-term upper limb dysfunction is common following nerve preserving surgery. The DASH questionnaire is a useful preoperative and postoperative clinical tool for those patients undergoing selective neck dissections. (c) 2009 Wiley Periodicals, Inc.

Dimeric combinations of MafB, cFos and cJun control the apoptosis-survival balance in limb morphogenesis.

PubMed

Suda, Natsuno; Itoh, Takehiko; Nakato, Ryuichiro; Shirakawa, Daisuke; Bando, Masashige; Katou, Yuki; Kataoka, Kohsuke; Shirahige, Katsuhiko; Tickle, Cheryll; Tanaka, Mikiko

2014-07-01

Apoptosis is an important mechanism for sculpting morphology. However, the molecular cascades that control apoptosis in developing limb buds remain largely unclear. Here, we show that MafB was specifically expressed in apoptotic regions of chick limb buds, and MafB/cFos heterodimers repressed apoptosis, whereas MafB/cJun heterodimers promoted apoptosis for sculpting the shape of the limbs. Chromatin immunoprecipitation sequencing in chick limb buds identified potential target genes and regulatory elements controlled by Maf and Jun. Functional analyses revealed that expression of p63 and p73, key components known to arrest the cell cycle, was directly activated by MafB and cJun. Our data suggest that dimeric combinations of MafB, cFos and cJun in developing chick limb buds control the number of apoptotic cells, and that MafB/cJun heterodimers lead to apoptosis via activation of p63 and p73. © 2014. Published by The Company of Biologists Ltd.

Movement analysis of upper limb during resistance training using general purpose robot arm "PA10"

NASA Astrophysics Data System (ADS)

Morita, Yoshifumi; Yamamoto, Takashi; Suzuki, Takahiro; Hirose, Akinori; Ukai, Hiroyuki; Matsui, Nobuyuki

2005-12-01

In this paper we perform movement analysis of an upper limb during resistance training. We selected sanding training, which is one type of resistance training for upper limbs widely performed in occupational therapy. Our final aims in the future are to quantitatively evaluate the therapeutic effect of upper limb motor function during training and to develop a new rehabilitation training support system. For these purposes, first of all we perform movement analysis using a conventional training tool. By measuring upper limb motion during the sanding training we perform feature abstraction. Next we perform movement analysis using the simulated sanding training system. This system is constructed using the general purpose robot arm "PA10". This system enables us to measure the force/torque exerted by subjects and to easily change the load of resistance. The control algorithm is based on impedance control. We found these features of the upper limb motion during the sanding training.

ITRAQ-based quantitative proteomic analysis of Cynops orientalis limb regeneration.

PubMed

Tang, Jie; Yu, Yuan; Zheng, Hanxue; Yin, Lu; Sun, Mei; Wang, Wenjun; Cui, Jihong; Liu, Wenguang; Xie, Xin; Chen, Fulin

2017-09-22

Salamanders regenerate their limbs after amputation. However, the molecular mechanism of this unique regeneration remains unclear. In this study, isobaric tags for relative and absolute quantification (iTRAQ) coupled with liquid chromatography tandem mass spectrometry (LC-MS/MS) was employed to quantitatively identify differentially expressed proteins in regenerating limbs 3, 7, 14, 30 and 42 days post amputation (dpa). Of 2636 proteins detected in total, 253 proteins were differentially expressed during different regeneration stages. Among these proteins, Asporin, Cadherin-13, Keratin, Collagen alpha-1(XI) and Titin were down-regulated. CAPG, Coronin-1A, AnnexinA1, Cathepsin B were up-regulated compared with the control. The identified proteins were further analyzed to obtain information about their expression patterns and functions in limb regeneration. Functional analysis indicated that the differentially expressed proteins were associated with wound healing, immune response, cellular process, metabolism and binding. This work indicated that significant proteome alternations occurred during salamander limb regeneration. The results may provide fundamental knowledge to understand the mechanism of limb regeneration.

Effect of bilateral lower limb strengthening exercise on balance and walking in hemiparetic patients after stroke: a randomized controlled trial.

PubMed

Jeon, Hye Joo; Hwang, Byong Yong

2018-02-01

[Purpose] To evaluate the effect of bilateral lower limb strengthening designed to improve balance and walking in stroke patients. [Subjects and Methods] Twenty hemiparetic stroke patients were divided into two groups: a unilateral therapy group (UTG) (n=10) and a bilateral therapy group (BTG) (n=10). The UTG completed strength training only in the paretic lower limb. The BTG completed strength training in the paretic and non-paretic lower limbs. Assessment tools included the functional reach test (FRT), the Berg balance scale (BBS), the timed up and go (TUG) test, and a 10-meter walk test (10MWT). [Results] In both groups, the lower limb strengthening exercise for balance and walking significantly improved the FRT, BBS, TUG, and 10MWT scores. Compared with UTG, the BTG attained significantly improved FRT and BBS scores. [Conclusion] Bilateral therapy using this lower limb strengthening exercise effectively promotes balance in hemiparetic stroke patients.

Constraints on arm selection processes when reaching: degrees of freedom and joint amplitudes interact to influence limb selection.

PubMed

Kim, Wondae; Buchanan, John; Gabbard, Carl

2011-01-01

With an interest in identifying the variables that constrain arm choice when reaching, the authors had 11 right-handed participants perform free-choice and assigned-limb reaches at 9 object positions. The right arm was freely selected 100% of the time when reaching to positions at 30° and 40° into right hemispace. However, the left arm was freely selected to reach to positions at -30° and -40° in left hemispace 85% of the time. A comparison between free- and assigned-limb reaching kinematics revealed that free limb selection when reaching to the farthest positions was constrained by joint amplitude requirements and the time devoted to limb deceleration. Differences between free- and assigned-arm reaches were not evident when reaching to the midline and positions of ±10°, even though the right arm was freely selected most often for these positions. Different factors contribute to limb selection as a function of distance into a specific hemispace.

LIMB-DARKENING COEFFICIENTS FOR ECLIPSING WHITE DWARFS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gianninas, A.; Strickland, B. D.; Kilic, Mukremin

2013-03-20

We present extensive calculations of linear and nonlinear limb-darkening coefficients as well as complete intensity profiles appropriate for modeling the light-curves of eclipsing white dwarfs. We compute limb-darkening coefficients in the Johnson-Kron-Cousins UBVRI photometric system as well as the Large Synoptic Survey Telescope (LSST) ugrizy system using the most up to date model atmospheres available. In all, we provide the coefficients for seven different limb-darkening laws. We describe the variations of these coefficients as a function of the atmospheric parameters, including the effects of convection at low effective temperatures. Finally, we discuss the importance of having readily available limb-darkening coefficientsmore » in the context of present and future photometric surveys like the LSST, Palomar Transient Factory, and the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS). The LSST, for example, may find {approx}10{sup 5} eclipsing white dwarfs. The limb-darkening calculations presented here will be an essential part of the detailed analysis of all of these systems.« less

Revised upper limb module for spinal muscular atrophy: Development of a new module.

PubMed

Mazzone, Elena S; Mayhew, Anna; Montes, Jacqueline; Ramsey, Danielle; Fanelli, Lavinia; Young, Sally Dunaway; Salazar, Rachel; De Sanctis, Roberto; Pasternak, Amy; Glanzman, Allan; Coratti, Giorgia; Civitello, Matthew; Forcina, Nicola; Gee, Richard; Duong, Tina; Pane, Marika; Scoto, Mariacristina; Pera, Maria Carmela; Messina, Sonia; Tennekoon, Gihan; Day, John W; Darras, Basil T; De Vivo, Darryl C; Finkel, Richard; Muntoni, Francesco; Mercuri, Eugenio

2017-06-01

There is a growing need for a robust clinical measure to assess upper limb motor function in spinal muscular atrophy (SMA), as the available scales lack sensitivity at the extremes of the clinical spectrum. We report the development of the Revised Upper Limb Module (RULM), an assessment specifically designed for upper limb function in SMA patients. An international panel with specific neuromuscular expertise performed a thorough review of scales currently available to assess upper limb function in SMA. This review facilitated a revision of the existing upper limb function scales to make a more robust clinical scale. Multiple revisions of the scale included statistical analysis and captured clinically relevant changes to fulfill requirements by regulators and advocacy groups. The resulting RULM scale shows good reliability and validity, making it a suitable tool to assess upper extremity function in the SMA population for multi-center clinical research. Muscle Nerve 55: 869-874, 2017. © 2016 Wiley Periodicals, Inc.

Distal Limb Patterning Requires Modulation of cis-Regulatory Activities by HOX13

DOE PAGES

Sheth, Rushikesh; Barozzi, Iros; Langlais, David; ...

2016-12-13

The combinatorial expression of Hox genes along the body axes is a major determinant of cell fate and plays a pivotal role in generating the animal body plan. Loss of HOXA13 and HOXD13 transcription factors (HOX13) leads to digit agenesis in mice, but how HOX13 proteins regulate transcriptional outcomes and confer identity to the distal-most limb cells has remained elusive. Here, we report on the genome-wide profiling of HOXA13 and HOXD13 in vivo binding and changes of the transcriptome and chromatin state in the transition from the early to the late-distal limb developmental program, as well as in Hoxa13–/–; Hoxd13–/– limbs. Ourmore » results show that proper termination of the early limb transcriptional program and activation of the late-distal limb program are coordinated by the dual action of HOX13 on cis-regulatory modules.« less

Limb darkening effect on transit light curves of HAT-P-32b

NASA Astrophysics Data System (ADS)

ćuha, H.; Erdem, A.

2018-02-01

The transit light curve of a transiting exoplanet offers us an opportunity to measure the fractional radius, semi-major axis and orbital inclination of the star-planet system. Precision of those parameters is strongly affected by limb darkening of the host star. In this study, we examine the limb darkening effect on the transit light curves of HAT-P-32b. The transit light curves of HAT-P-32b were observed on three nights at TUBITAK National Observatory with a 100-cm aperture telescope in Bessel R and V filters. The light curves were solved using jktebop code. Linear, square root, logarithmic and quadratic limb darkening laws were taken into account during the analysis. The derived limb darkening coefficients from our observations were then compared with theoretical values given in the literature. We conclude that more sensitive data, such as space based photometric observations, are needed in order to determine the limb darkening coefficients accurately.

Effect of bilateral lower limb strengthening exercise on balance and walking in hemiparetic patients after stroke: a randomized controlled trial

PubMed Central

Jeon, Hye Joo; Hwang, Byong Yong

2018-01-01

[Purpose] To evaluate the effect of bilateral lower limb strengthening designed to improve balance and walking in stroke patients. [Subjects and Methods] Twenty hemiparetic stroke patients were divided into two groups: a unilateral therapy group (UTG) (n=10) and a bilateral therapy group (BTG) (n=10). The UTG completed strength training only in the paretic lower limb. The BTG completed strength training in the paretic and non-paretic lower limbs. Assessment tools included the functional reach test (FRT), the Berg balance scale (BBS), the timed up and go (TUG) test, and a 10-meter walk test (10MWT). [Results] In both groups, the lower limb strengthening exercise for balance and walking significantly improved the FRT, BBS, TUG, and 10MWT scores. Compared with UTG, the BTG attained significantly improved FRT and BBS scores. [Conclusion] Bilateral therapy using this lower limb strengthening exercise effectively promotes balance in hemiparetic stroke patients. PMID:29545693

HAND2 Targets Define a Network of Transcriptional Regulators that Compartmentalize the Early Limb Bud Mesenchyme

DOE PAGES

Osterwalder, Marco; Speziale, Dario; Shoukry, Malak; ...

2014-11-10

The genetic networks that govern vertebrate development are well studied, but how the interactions of trans-acting factors with cis-regulatory modules (CRMs) are integrated into spatiotemporal regulation of gene expression is not clear. The transcriptional regulator HAND2 is required during limb, heart, and branchial arch development. Here, we identify the genomic regions enriched in HAND2 chromatin complexes from mouse embryos and limb buds. Then we analyze the HAND2 target CRMs in the genomic landscapes encoding transcriptional regulators required in early limb buds. HAND2 controls the expression of genes functioning in the proximal limb bud and orchestrates the establishment of anterior andmore » posterior polarity of the nascent limb bud mesenchyme by impacting Gli3 and Tbx3 expression. TBX3 is required downstream of HAND2 to refine the posterior Gli3 expression boundary. In conclusion, our analysis uncovers the transcriptional circuits that function in establishing distinct mesenchymal compartments downstream of HAND2 and upstream of SHH signaling.« less

Assisting children with Attention Deficit Hyperactivity Disorder actively reduces limb hyperactive behavior with a Nintendo Wii Remote Controller through controlling environmental stimulation.

PubMed

Shih, Ching-Hsiang; Yeh, Jui-Chi; Shih, Ching-Tien; Chang, Man-Ling

2011-01-01

The latest studies have adopted software technology which turns the Wii Remote Controller into a high-performance limb action detector, we assessed whether two persons with multiple disabilities would be able to control an environmental stimulus through limb action. This study extends the functionality of the Wii Remote Controller to the correction of limb hyperactive behavior to assess whether two children with Attention Deficit Hyperactivity Disorder (ADHD) would be able to actively reduce their limb hyperactive behavior through controlling their favorite stimuli by turning them on/off using a Wii Remote Controller. An ABAB design, in which A represented the baseline and B represented intervention phases, was adopted in this study. Result showed that both participants significantly increased their time duration of maintaining a static limb posture (TDMSLP) to activate the control system in order to produce environmental stimulation in the intervention phases. Practical and developmental implications of the findings are discussed. Copyright © 2011 Elsevier Ltd. All rights reserved.

Phantom motor execution facilitated by machine learning and augmented reality as treatment for phantom limb pain: a single group, clinical trial in patients with chronic intractable phantom limb pain.

PubMed

Ortiz-Catalan, Max; Guðmundsdóttir, Rannveig A; Kristoffersen, Morten B; Zepeda-Echavarria, Alejandra; Caine-Winterberger, Kerstin; Kulbacka-Ortiz, Katarzyna; Widehammar, Cathrine; Eriksson, Karin; Stockselius, Anita; Ragnö, Christina; Pihlar, Zdenka; Burger, Helena; Hermansson, Liselotte

2016-12-10

Phantom limb pain is a debilitating condition for which no effective treatment has been found. We hypothesised that re-engagement of central and peripheral circuitry involved in motor execution could reduce phantom limb pain via competitive plasticity and reversal of cortical reorganisation. Patients with upper limb amputation and known chronic intractable phantom limb pain were recruited at three clinics in Sweden and one in Slovenia. Patients received 12 sessions of phantom motor execution using machine learning, augmented and virtual reality, and serious gaming. Changes in intensity, frequency, duration, quality, and intrusion of phantom limb pain were assessed by the use of the numeric rating scale, the pain rating index, the weighted pain distribution scale, and a study-specific frequency scale before each session and at follow-up interviews 1, 3, and 6 months after the last session. Changes in medication and prostheses were also monitored. Results are reported using descriptive statistics and analysed by non-parametric tests. The trial is registered at ClinicalTrials.gov, number NCT02281539. Between Sept 15, 2014, and April 10, 2015, 14 patients with intractable chronic phantom limb pain, for whom conventional treatments failed, were enrolled. After 12 sessions, patients showed statistically and clinically significant improvements in all metrics of phantom limb pain. Phantom limb pain decreased from pre-treatment to the last treatment session by 47% (SD 39; absolute mean change 1·0 [0·8]; p=0·001) for weighted pain distribution, 32% (38; absolute mean change 1·6 [1·8]; p=0·007) for the numeric rating scale, and 51% (33; absolute mean change 9·6 [8·1]; p=0·0001) for the pain rating index. The numeric rating scale score for intrusion of phantom limb pain in activities of daily living and sleep was reduced by 43% (SD 37; absolute mean change 2·4 [2·3]; p=0·004) and 61% (39; absolute mean change 2·3 [1·8]; p=0·001), respectively. Two of four patients who were on medication reduced their intake by 81% (absolute reduction 1300 mg, gabapentin) and 33% (absolute reduction 75 mg, pregabalin). Improvements remained 6 months after the last treatment. Our findings suggest potential value in motor execution of the phantom limb as a treatment for phantom limb pain. Promotion of phantom motor execution aided by machine learning, augmented and virtual reality, and gaming is a non-invasive, non-pharmacological, and engaging treatment with no identified side-effects at present. Promobilia Foundation, VINNOVA, Jimmy Dahlstens Fond, PicoSolve, and Innovationskontor Väst. Copyright © 2016 Elsevier Ltd. All rights reserved.

Treating peripheral arterial disease percutaneously with atherectomy.

PubMed

Schwartz, Bryan G; Kloner, Robert A; Burstein, Steven; Economides, Christina; Mayeda, Guy S

2012-06-01

To determine clinical outcomes of patients who underwent percutaneous revascularization (PR) with multiple devices. PR cases at a private, tertiary referral hospital were reviewed retrospectively. Limb salvage and patency rates were calculated by the Kaplan Meier method. Historical and procedural factors were analyzed by multivariate Cox proportional hazards models. We identified 66 patients and 87 limbs with 261 lesions, including 38 patients with critical limb ischemia (CLI) (51 limbs, 171 lesions). PR incorporated multiple devices (2.0 ± 1.2 devices/lesion, 2.4 ± 1.6 devices/procedure), including balloon angioplasty (57%), excisional atherectomy (54%), orbital atherectomy (44%), and stenting (13%). Last imaged patency was at 18 ± 13 months and last clinical follow-up was 22 ± 12 months. Thirty-five of 87 limbs had ≥1 repeat PR. In 51 limbs with CLI, limb salvage was 75% at 3 years. Independent predictors of amputation were higher creatinine (P=.01; hazard ratio [HR], 1.4), Rutherford category (P=.03; HR, 3.5), and history of coronary artery bypass graft (CABG) (P=.03; HR, 8.9). Overall patency remained 75% through 3 years. Loss of patency or primary patency (patency without repeat PR) was predicted by higher creatinine, Rutherford category, chronic total occlusion, history of CABG, female gender, current and past smoking. Use of excisional atherectomy maintained overall patency (P=.01; HR, 0.36). An aggressive approach to PR with frequent use of atherectomy resulted in high rates of limb salvage and patency. Smoking cessation and excisional atherectomy may improve patency rates.

Correlation of Meniscal T2* with Multiphoton Microscopy, and Change of Articular Cartilage T2 in an Ovine Model of Meniscal Repair

PubMed Central

Koff, Matthew F.; Shah, Parina; Pownder, Sarah; Romero, Bethsabe; Williams, Rebecca; Gilbert, Susannah; Maher, Suzanne; Fortier, Lisa A.; Rodeo, Scott A.; Potter, Hollis G.

2013-01-01

Objective To correlate meniscal T2* relaxation times using ultra-short echo time (UTE) magnetic resonance imaging (MRI) with quantitative microscopic methods, and to determine the effect of meniscal repair on post-operative cartilage T2 values. Design A medial meniscal tear was created and repaired in the anterior horn of one limb of 28 crossbred mature ewes. MR scans for morphological evaluation, meniscal T2* values, and cartilage T2 values were acquired at 0, 4 and 8 months post-operatively for the Tear and Non-Op limb. Samples of menisci from both limbs were analyzed using multiphoton microscopy (MPM) analysis and biomechanical testing. Results Significantly prolonged meniscal T2* values were found in repaired limbs than in control limbs, p<0.0001. No regional differences of T2* were detected for either the repaired or control limbs in the anterior horn. Repaired limbs had prolonged cartilage T2 values, primarily anteriorly, and tended to have lower biomechanical force to failure at 8 months than Non-Op limbs. MPM autofluorescence and second harmonic generation data correlated with T2* values at 8 months (ρ=−0.48, p=0.06). Conclusions T2* mapping is sensitive to detecting temporal and zonal differences of meniscal structure and composition. Meniscal MPM and cartilage T2 values indicate changes in tissue integrity in the presence of meniscal repair. PMID:23680878

Neuregulin-1 signaling is essential for nerve-dependent axolotl limb regeneration.

PubMed

Farkas, Johanna E; Freitas, Polina D; Bryant, Donald M; Whited, Jessica L; Monaghan, James R

2016-08-01

The Mexican axolotl (Ambystoma mexicanum) is capable of fully regenerating amputated limbs, but denervation of the limb inhibits the formation of the post-injury proliferative mass called the blastema. The molecular basis behind this phenomenon remains poorly understood, but previous studies have suggested that nerves support regeneration via the secretion of essential growth-promoting factors. An essential nerve-derived factor must be found in the blastema, capable of rescuing regeneration in denervated limbs, and its inhibition must prevent regeneration. Here, we show that the neuronally secreted protein Neuregulin-1 (NRG1) fulfills all these criteria in the axolotl. Immunohistochemistry and in situ hybridization of NRG1 and its active receptor ErbB2 revealed that they are expressed in regenerating blastemas but lost upon denervation. NRG1 was localized to the wound epithelium prior to blastema formation and was later strongly expressed in proliferating blastemal cells. Supplementation by implantation of NRG1-soaked beads rescued regeneration to digits in denervated limbs, and pharmacological inhibition of NRG1 signaling reduced cell proliferation, blocked blastema formation and induced aberrant collagen deposition in fully innervated limbs. Taken together, our results show that nerve-dependent NRG1/ErbB2 signaling promotes blastemal proliferation in the regenerating limb and may play an essential role in blastema formation, thus providing insight into the longstanding question of why nerves are required for axolotl limb regeneration. © 2016. Published by The Company of Biologists Ltd.

Activation of germline-specific genes is required for limb regeneration in the Mexican axolotl

PubMed Central

Zhu, Wei; Pao, Gerald M; Satoh, Akira; Cummings, Gillian; Monaghan, James R; Harkins, Timothy T; Bryant, Susan V; Voss, S Randal; Gardiner, David M; Hunter, Tony

2013-01-01

The capacity for tissue and organ regeneration in humans is dwarfed by comparison to that of salamanders. Emerging evidence suggests that mechanisms learned from the early phase of salamander limb regeneration – wound healing, cellular dedifferentiation and blastemal formation – will reveal therapeutic approaches for tissue regeneration in humans. Here we describe a unique transcriptional fingerprint of regenerating limb tissue in the Mexican axolotl (Ambystoma mexicanum) that is indicative of cellular reprogramming of differentiated cells to a germline-like state. Two genes that are required for self-renewal of germ cells in mice and flies, Piwi-like 1 (PL1) and Piwi-like 2 (PL2), are expressed in limb blastemal cells, the basal layer keratinocytes and the thickened apical epithelial cap in the wound epidermis in the regenerating limb. Depletion of PL1 and PL2 by morpholino oligonucleotides decreased cell proliferation and increased cell death in the blastema leading to a significant retardation of regeneration. Examination of key molecules that are known to be required for limb development or regeneration further revealed that FGF8 is transcriptionally downregulated in the presence of the morpholino oligos, indicating PL1 and PL2 might participate in FGF signaling during limb regeneration. Given the requirement for FGF signaling in limb development and regeneration, the results suggest that PL1 and PL2 function to establish a unique germline-like state that is associated with successful regeneration. PMID:22841627

Correlation of ankle eversion to inversion strength ratio and static balance in dominant and non-dominant limbs of basketball players.

PubMed

Dabadghav, Rachana

2016-04-01

To compare ankle eversion to inversion strength ratio (E/I R) and static balance control between the dominant and non-dominant limbs of basketball players and to correlate ankle E/I R and static balance control in the dominant and non-dominant limbs of basketball players. Twenty-one healthy basketball players in the age-group of 18-25 years participated in this study. Isokinetic ankle eversion and inversion muscle strength was assessed at 30°/s and 120°/s in both dominant and non-dominant limbs using the Biodex isokinetic dynamometer. Similarly balance was assessed on a force platform with eyes open and eyes closed in both dominant and non-dominant limbs. Repeated measure ANOVA for strength measurement, found that there was significant main effect of speed, P=0.001 (P<0.05). However, there was no significant main effect in the sides P=0.099 (P<0.05).There was significant main effect of sides with respect to balance. Balance was affected more in non-dominant limb P=0.000 as compared to dominant limb. However, there was not much of a significant difference with eyes open and eyes closed position. The E/I ratio was >1.0 at the angular velocity of 120°/s increasing the chances of ankle injuries in basketball players. There was no correlation between ankle strength and balance in both dominant and non-dominant limbs.

3D optical imagery for motion compensation in a limb ultrasound system

NASA Astrophysics Data System (ADS)

Ranger, Bryan J.; Feigin, Micha; Zhang, Xiang; Mireault, Al; Raskar, Ramesh; Herr, Hugh M.; Anthony, Brian W.

2016-04-01

Conventional processes for prosthetic socket fabrication are heavily subjective, often resulting in an interface to the human body that is neither comfortable nor completely functional. With nearly 100% of amputees reporting that they experience discomfort with the wearing of their prosthetic limb, designing an effective interface to the body can significantly affect quality of life and future health outcomes. Active research in medical imaging and biomechanical tissue modeling of residual limbs has led to significant advances in computer aided prosthetic socket design, demonstrating an interest in moving toward more quantifiable processes that are still patient-specific. In our work, medical ultrasonography is being pursued to acquire data that may quantify and improve the design process and fabrication of prosthetic sockets while greatly reducing cost compared to an MRI-based framework. This paper presents a prototype limb imaging system that uses a medical ultrasound probe, mounted to a mechanical positioning system and submerged in a water bath. The limb imaging is combined with three-dimensional optical imaging for motion compensation. Images are collected circumferentially around the limb and combined into cross-sectional axial image slices, resulting in a compound image that shows tissue distributions and anatomical boundaries similar to magnetic resonance imaging. In this paper we provide a progress update on our system development, along with preliminary results as we move toward full volumetric imaging of residual limbs for prosthetic socket design. This demonstrates a novel multi-modal approach to residual limb imaging.

Influence of Ribeiroia ondatrae (Trematoda: Digenea) infection on limb development and survival of northern leopard frogs (Rana pipiens): effects of host stage and parasite-exposure level

USGS Publications Warehouse

Schotthoefer, Anna M.; Koehler, Anson V.; Meteyer, Carol U.; Cole, Rebecca A.

2003-01-01

Recent evidence suggests that infection by larvae of the trematode Ribeiroia ondatrae accounts for a significant proportion of limb malformations currently observed in amphibian populations of North America. However, the effects of R. ondatrae infection on northern leopard frogs (Rana pipiens), one of the species most frequently reported with malformations, have not been adequately explored. Moreover, the risk factors associated with R. ondatrae-induced malformations have not been clearly identified. We examined the effects of timing of infection on tadpole survival and limb development. Rana pipiens tadpoles were individually exposed to R. ondatrae cercariae at the pre-limb-bud (Gosner stages 24 and 25), limb-bud (Gosner stages 27 and 28), or paddle (Gosner stages 31–33) stages of development and monitored through metamorphosis. The effects of infection were stage-specific. Infections acquired at the pre-limb-bud stage resulted in a high mortality rate (47.5–97.5%), whereas tadpoles infected at the limb-bud stage displayed a high malformation rate (16% overall), and the magnitude of effects increased with the level of exposure to cercariae. In contrast, infections acquired at the paddle stage had no effect on limb development or tadpole survival, which suggests that the timing of R. ondatrae infection in relation to the stage structure of tadpole populations in the wild is an important determinant of the degree to which populations are affected by R. ondatrae.

Modeling rate sensitivity of exercise transient responses to limb motion.

PubMed

Yamashiro, Stanley M; Kato, Takahide

2014-10-01

Transient responses of ventilation (V̇e) to limb motion can exhibit predictive characteristics. In response to a change in limb motion, a rapid change in V̇e is commonly observed with characteristics different than during a change in workload. This rapid change has been attributed to a feed-forward or adaptive response. Rate sensitivity was explored as a specific hypothesis to explain predictive V̇e responses to limb motion. A simple model assuming an additive feed-forward summation of V̇e proportional to the rate of change of limb motion was studied. This model was able to successfully account for the adaptive phase correction observed during human sinusoidal changes in limb motion. Adaptation of rate sensitivity might also explain the reduction of the fast component of V̇e responses previously reported following sudden exercise termination. Adaptation of the fast component of V̇e response could occur by reduction of rate sensitivity. Rate sensitivity of limb motion was predicted by the model to reduce the phase delay between limb motion and V̇e response without changing the steady-state response to exercise load. In this way, V̇e can respond more quickly to an exercise change without interfering with overall feedback control. The asymmetry between responses to an incremental and decremental ramp change in exercise can also be accounted for by the proposed model. Rate sensitivity leads to predicted behavior, which resembles responses observed in exercise tied to expiratory reserve volume. Copyright © 2014 the American Physiological Society.

Temporary arterial shunts to maintain limb perfusion after arterial injury: an animal study

NASA Technical Reports Server (NTRS)

Dawson, D. L.; Putnam, A. T.; Light, J. T.; Ihnat, D. M.; Kissinger, D. P.; Rasmussen, T. E.; Bradley, D. V. Jr

1999-01-01

BACKGROUND: Temporary shunt placement can quickly restore perfusion after extremity arterial injury. This study examined the adequacy of limb blood flow with shunt use, non-heparin-bonded shunt patency over prolonged periods, and the safety of this technique. METHODS: Common iliac arteries were divided and 4.0-mm Silastic Sundt shunts placed in 16 anesthetized pigs. Eight (group I) had shunts placed immediately; eight others (group II) were shunted after an hour of limb ischemia and hemorrhagic shock. Physiologic parameters and femoral artery blood flow in both hindlimbs were continuously monitored. Limb lactic acid generation, oxygen utilization, and hematologic and metabolic effects were serially evaluated for 24 hours. RESULTS: Shunts remained patent in 13 of 16 pigs. Shunts thrombosed in two group I animals because of technical errors, but functioned well after thrombectomy and repositioning. Patency could not be maintained in one animal that died from shock. Flow in group I shunted limbs was 57 (+/-11 SD) % of control. For group II animals in shock, shunted limb flow initially averaged 46 +/- 15% of control, but 4 hours after shunt placement, the mean limb blood flow was the same as in group I. Increased oxygen extraction compensated for the lower flow. Lactic acid production was not increased in comparison to control limbs. CONCLUSION: Shunts provided adequate flow in this model of extremity trauma. Correctly placed shunts stayed patent for 24 hours, without anticoagulation, if shunt placement followed resuscitation.

A comparative study of single-leg ground reaction forces in running lizards.

PubMed

McElroy, Eric J; Wilson, Robbie; Biknevicius, Audrone R; Reilly, Stephen M

2014-03-01

The role of different limbs in supporting and propelling the body has been studied in many species with animals appearing to have either similarity in limb function or differential limb function. Differential hindlimb versus forelimb function has been proposed as a general feature of running with a sprawling posture and as benefiting sprawled postured animals by enhancing maneuvering and minimizing joint moments. Yet only a few species have been studied and thus the generality of differential limb function in running animals with sprawled postures is unknown. We measured the limb lengths of seven species of lizard and their single-limb three-dimensional ground reaction forces during high-speed running. We found that all species relied on the hindlimb for producing accelerative forces. Braking forces were forelimb dominated in four species and equally distributed between limbs in the other three. Vertical forces were dominated by the hindlimb in three species and equally distributed between the forelimb and hindlimb in the other four. Medial forces were dominated by the hindlimb in four species and equally distributed in the other three, with all Iguanians exhibiting hindlimb-biased medial forces. Relative hindlimb to forelimb length of each species was related to variation in hindlimb versus forelimb medial forces; species with relatively longer hindlimbs compared with forelimbs exhibited medial forces that were more biased towards the hindlimbs. These results suggest that the function of individual limbs in lizards varies across species with only a single general pattern (hindlimb-dominated accelerative force) being present.

Alcohol affects executive cognitive functioning differentially on the ascending versus descending limb of the blood alcohol concentration curve.

PubMed

Pihl, Robert O; Paylan, Sheila S; Gentes-Hawn, Alyson; Hoaken, Peter N S

2003-05-01

Executive cognitive functioning (ECF), a construct that includes cognitive abilities such as planning, abstract reasoning, and the capacity to govern self-directed behavior, has been recently researched as an antecedent to many forms of psychopathology and has been implicated in alcohol-related aggression. This study was designed to examine whether differential ECF impairments can be noted on the ascending versus the descending limbs of the blood alcohol concentration curve. Forty-one male university students participated in this study. Twenty-one subjects were given 1.32 ml of 95% alcohol per kilogram of body weight, mixed with orange juice, and the remaining 20 were given a placebo. Participants were randomly assigned to either an ascending or descending blood alcohol group and were tested on six tests of ECF on their assigned limb. Subjective mood data were also collected. Intoxicated participants on both limbs demonstrated ECF impairment; the descending-limb group showed greater impairment than their ascending-limb counterparts. Intoxicated subjects were significantly more anxious at baseline than placebo subjects. The introduction of this covariate nullified any significant differences in subjective mood found on either limb of the blood alcohol concentration curve, but ECF impairments remained robust. Our results support the conclusion that alcohol negatively affects cognitive performance and has a differential effect on the descending versus the ascending limb of the blood alcohol concentration curve. The latter finding may have important ramifications relating to the detrimental consequences of alcohol intoxication.

Limb Darkening and Planetary Transits: Testing Center-to-limb Intensity Variations and Limb-darkening Directly from Model Stellar Atmospheres

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neilson, Hilding R.; Lester, John B.; McNeil, Joseph T.

The transit method, employed by Microvariability and Oscillation of Stars ( MOST ), Kepler , and various ground-based surveys has enabled the characterization of extrasolar planets to unprecedented precision. These results are precise enough to begin to measure planet atmosphere composition, planetary oblateness, starspots, and other phenomena at the level of a few hundred parts per million. However, these results depend on our understanding of stellar limb darkening, that is, the intensity distribution across the stellar disk that is sequentially blocked as the planet transits. Typically, stellar limb darkening is assumed to be a simple parameterization with two coefficients thatmore » are derived from stellar atmosphere models or fit directly. In this work, we revisit this assumption and compute synthetic planetary-transit light curves directly from model stellar atmosphere center-to-limb intensity variations (CLIVs) using the plane-parallel Atlas and spherically symmetric SAtlas codes. We compare these light curves to those constructed using best-fit limb-darkening parameterizations. We find that adopting parametric stellar limb-darkening laws leads to systematic differences from the more geometrically realistic model stellar atmosphere CLIV of about 50–100 ppm at the transit center and up to 300 ppm at ingress/egress. While these errors are small, they are systematic, and they appear to limit the precision necessary to measure secondary effects. Our results may also have a significant impact on transit spectra.« less

The functional anatomy of suggested limb paralysis.

PubMed

Deeley, Quinton; Oakley, David A; Toone, Brian; Bell, Vaughan; Walsh, Eamonn; Marquand, Andre F; Giampietro, Vincent; Brammer, Michael J; Williams, Steven C R; Mehta, Mitul A; Halligan, Peter W

2013-02-01

Suggestions of limb paralysis in highly hypnotically suggestible subjects have been employed to successfully model conversion disorders, revealing similar patterns of brain activation associated with attempted movement of the affected limb. However, previous studies differ with regard to the executive regions involved during involuntary inhibition of the affected limb. This difference may have arisen as previous studies did not control for differences in hypnosis depth between conditions and/or include subjective measures to explore the experience of suggested paralysis. In the current study we employed functional magnetic resonance imaging (fMRI) to examine the functional anatomy of left and right upper limb movements in eight healthy subjects selected for high hypnotic suggestibility during (i) hypnosis (NORMAL) and (ii) attempted movement following additional left upper limb paralysis suggestions (PARALYSIS). Contrast of left upper limb motor function during NORMAL relative to PARALYSIS conditions revealed greater activation of contralateral M1/S1 and ipsilateral cerebellum, consistent with the engagement of these regions in the completion of movements. By contrast, two significant observations were noted in PARALYSIS relative to NORMAL conditions. In conjunction with reports of attempts to move the paralysed limb, greater supplementary motor area (SMA) activation was observed, a finding consistent with the role of SMA in motor intention and planning. The anterior cingulate cortex (ACC, BA 24) was also significantly more active in PARALYSIS relative to NORMAL conditions - suggesting that ACC (BA 24) may be implicated in involuntary, as well as voluntary inhibition of prepotent motor responses. Copyright © 2012 Elsevier Ltd. All rights reserved.

Chicken homeobox gene Msx-1: structure, expression in limb buds and effect of retinoic acid.

PubMed

Yokouchi, Y; Ohsugi, K; Sasaki, H; Kuroiwa, A

1991-10-01

A chicken gene carrying a homeobox highly homologous to the Drosophila muscle segment homeobox (msh) gene was isolated and designated as Msx-1. Conceptual translation from the longest ORF gave a protein of 259 amino acids lacking the conserved hexapeptide. Northern analysis detected a single 2.6 kb transcript. As early as day 2 of incubation, the transcript was detected but was not found in adult tissue. In situ hybridization analysis revealed that Msx-1 expression is closely related to a particular mesenchymal cell lineage during limb bud formation. In early stage embryos, Msx-1 was expressed in the somatopleure. When primordial mesenchyme cells for limb bud were generated from the Wolffian ridge of the somatopleure, Msx-1 expression began to diminish in the posterior half of the limb bud then in the presumptive cartilage-forming mesenchyme. In developing limb buds, remarkable expression was seen in the apical ectodermal ridge (AER), which is responsible for the sustained outgrowth and development of the limb. The Msx-1 transcripts were found in the limb mesenchymal cells in the region covering the necrotic zone and ectodermal cells overlying such mesenchymal cells. Both ectodermal and mesenchymal expression in limb bud were rapidly suppressed by local treatment of retinoic acid which can generate mirror-image duplication of digits. This indicates that retinoic acid alters the marginal presumptive non-cartilage forming mesenchyme cell lineage through suppression of Msx-1 expression.

Residual limb skin temperature and thermal comfort in people with amputation during activity in a cold environment.

PubMed

Segal, Ava D; Klute, Glenn K

2016-01-01

Thermal comfort remains a common problem for people with lower-limb amputation. Both donning a prosthesis and engaging in activity at room temperature can increase residual limb skin temperature; however, the effects of activity on skin temperature and comfort in more extreme environments remain unknown. We examined residual limb skin temperatures and perceived thermal comfort (PTC; 11-point Likert scale) of participants with unilateral transtibial amputation (n = 8) who were snowshoeing in a cold environment. Residual limb skin temperature increased by 3.9°C [3.0°C to 4.7°C] (mean difference [95% confidence interval (CI)], p < 0.001) after two 30 min exercise sessions separated by a 5 min rest session. Minimal cooling (-0.2°C [-1.1°C to 0.6°C]) occurred during the rest period. Similar changes in PTC were found for the residual limb, intact limb, and whole body, with a mean scale increase of 1.6 [1.1 to 2.1] and 1.3 [0.8 to 1.8] for the first and second exercise sessions, respectively (p < 0.001). Activity in a cold environment caused similar increases in residual limb skin temperature as those found in studies conducted at room temperature. Participants with amputation perceived warming as their skin temperature increased during exercise followed by the perception of cooling during rest, despite minimal associated decreases in skin temperature.

Length asymmetry of the bovine digits.

PubMed

Muggli, E; Sauter-Louis, C; Braun, U; Nuss, K

2011-06-01

The lengths of the digital bones of the fore- and hind-limbs obtained post mortem from 40 cattle of different ages were measured using digital radiographs. The lengths of the individual digital bones and the overall length of the digit were determined using computer software. The lateral metacarpal/metatarsal condyle, and lateral P1 and P2 were significantly longer than their medial counterparts, whereas P3 of the medial digit was longer than its lateral partner. Measured from the cannon bone epiphysis to the tip of the pedal bone, the mean increased length of the lateral digit was 0.8 mm in the fore- and 1.5 mm in the hind-limb. When the lengths of the digital bones were summed, the mean length of the lateral digit was 1.8 mm longer in the fore-limb and 2.1 mm longer in the hind-limb. Based on these findings, it can be concluded that the lengths of the paired digits differ in cattle. The majority of cattle have longer lateral digits in the fore- and hind-limbs. This asymmetry might explain why the lateral hind-limb claws are predisposed to sole ulcers on hard surfaces. In the hind-limbs, the impact is transferred from the pelvis directly to the longer lateral digit. In the fore-limb claws, the tenomuscular attachment to the trunk may be involved in a more even weight distribution and in a shift of weight to the medial claw. Copyright © 2010 Elsevier Ltd. All rights reserved.

The origin of mean arterial and jugular venous blood pressures in giraffes.

PubMed

Mitchell, Graham; Maloney, Shane K; Mitchell, Duncan; Keegan, D James

2006-07-01

Using a mechanical model of the giraffe neck and head circulation consisting of a rigid, ascending, 'carotid' limb, a 'cranial' circulation that could be rigid or collapsible, and a descending, 'jugular' limb that also could be rigid or collapsible, we have analyzed the origin of the high arterial and venous pressures in giraffe, and whether blood flow is assisted by a siphon. When the tubes were rigid and the 'jugular' limb exit was lower than the 'carotid' limb entrance a siphon operated, 'carotid' hydrostatic pressures became more negative, and flow was 3.3 l min(-1) but ceased when the 'cranial' and 'jugular' limbs were collapsible or when the 'jugular' limb was opened to the atmosphere. Pumping water through the model produced positive pressures in the 'carotid' limb similar to those found in giraffe. Applying an external 'tissue' pressure to the 'jugular' tube during pump flow produced the typical pressures found in the jugular vein in giraffe. Constriction of the lowest, 'jugular cuff', portion of the 'jugular' limb showed that the cuff may augment the orthostatic reflex during head raising. Except when all tubes were rigid, pressures were unaffected by a siphon. We conclude that mean arterial blood pressure in giraffes is a consequence of the hydrostatic pressure generated by the column of blood in the neck, that tissue pressure around the collapsible jugular vein produces the known jugular pressures, and that a siphon does not assist flow through the cranial circulation.

Mirror therapy in complex regional pain syndrome type 1 of the upper limb in stroke patients.

PubMed

Cacchio, Angelo; De Blasis, Elisabetta; De Blasis, Vincenzo; Santilli, Valter; Spacca, Giorgio

2009-10-01

Complex regional pain syndrome type 1 (CRPSt1) of the upper limb is a painful and debilitating condition, frequent after stroke, and interferes with the rehabilitative process and outcome. However, treatments used for CRPSt1 of the upper limb are limited. . This randomized controlled study was conducted to compare the effectiveness on pain and upper limb function of mirror therapy on CRPSt1 of upper limb in patients with acute stroke. . Of 208 patients with first episode of unilateral stroke admitted to the authors' rehabilitation center, 48 patients with CRPSt1 of the affected upper limb were enrolled in a randomized controlled study, with a 6-month follow-up, and assigned to either a mirror therapy group or placebo control group. The primary end points were a reduction in the visual analogue scale score of pain at rest, on movement, and brush-induced tactile allodynia. The secondary end points were improvement in motor function as assessed by the Wolf Motor Function Test and Motor Activity Log. . The mean scores of both the primary and secondary end points significantly improved in the mirror group (P < .001). No statistically significant improvement was observed in any of the control group values (P > .001). Moreover, statistically significant differences after treatment (P < .001) and at the 6-month follow-up were found between the 2 groups. . The results indicate that mirror therapy effectively reduces pain and enhances upper limb motor function in stroke patients with upper limb CRPSt1.

Manometry of the Upper Gut Following Roux-en-Y Gastric Bypass Indicates That the Gastric Pouch and Roux Limb Act as a Common Cavity.

PubMed

Björklund, Per; Lönroth, Hans; Fändriks, Lars

2015-10-01

The motility of the upper gut after Roux-en-Y gastric bypass (RYGBP) is underexplored. We aimed to investigate the oesophago-gastro-Roux limb motor activity during fasting and after food intake. Eighteen morbidly obese patients were examined at least 2 years after RYGBP. A high-resolution manometry catheter was positioned to straddle the oesophagogastric junction, the gastric pouch and the proximal Roux limb using transmucosal potential difference measurements. Three patients with vertical banded gastroplasty (VBG) were also studied. During the fasting state, the gastric pouch had low or no activity whereas the Roux limb exhibited regular migrating motility complexes (MMCs) being initiated just distal to gastroenteroanastomosis. Median cycle duration was 72 min, and the median propagating velocity of the phase III MMC phase was 2.7 cm/min (n = 8). When patients were asked to eat until they felt comfortably full, intraluminal pressure increased by 6 to 8 cmH₂O without any significant difference between gastric pouch and the Roux limb (n = 9). The increased intraluminal pressure following food intake correlated neither to weight loss nor to meal size or rate of eating. A successful RYGBP is associated with MMC in the Roux limb during fasting. The gastric pouch and the Roux limb behaved as a common cavity during food ingestion. Data do not support the hypothesis that the alimentary limb pressure in response to food intake influences either meal size or weight loss.

Prevalence of upper limb disorders among female librarians.

PubMed

Pandy, R

2013-09-01

Work as a librarian involves exposure to potential risk factors for developing upper limb disorders. The prevalence of upper limb symptoms has, however, not previously been assessed in this occupational group. To estimate the 7-day and annual prevalence of self-reported neck and upper limb symptoms in librarians and to examine associations with specific tasks and ergonomic risk factors. A cross-sectional study using components of the standardized Nordic questionnaire. The study population consisted of librarians employed by a large local authority, and data collection was by means of a self-administered questionnaire. from studies on keyboard workers and on the general population were used as comparators. The 7-day prevalence of self-reported neck and upper limb pain in female librarians was 42% (95% confidence interval (CI) 33.7-50.5) and the annual prevalence was 65% (95% CI 56.6-72.8). The prevalence of reported wrist and hand pain increased with increased working involving a wide thumb-index span (P < 0.05) with a significant linear trend in prevalence with increasing exposure (P < 0.01). There was a strong association between reporting hand and/or wrist pain and awareness of work-related upper limb disorder (P < 0.05). The annual prevalence of self-reported upper limb symptoms among female librarians was high, but there was insufficient evidence to confirm whether the prevalence was higher than in the general population or among keyboard workers. Working with a wide thumb-index span was associated with reporting upper limb symptoms.

EFFECTS OF ETHANOL AND HYDROGEN PEROXIDE ON MOUSE LIMB BUD MESENCHYME DIFFERENTIATION AND CELL DEATH

EPA Science Inventory

Many of the morphological defects associated with embryonic alcohol exposure are a result of cell death. During limb development, ethanol administration produces cell death in the limb and digital defects, including postaxial ectrodactyly. Because an accumulation of reactive oxyg...

21 CFR 890.3475 - Limb orthosis.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Limb orthosis. 890.3475 Section 890.3475 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3475 Limb orthosis. (a) Identification...

21 CFR 890.3475 - Limb orthosis.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Limb orthosis. 890.3475 Section 890.3475 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3475 Limb orthosis. (a) Identification...

21 CFR 890.3475 - Limb orthosis.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Limb orthosis. 890.3475 Section 890.3475 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3475 Limb orthosis. (a) Identification...

21 CFR 890.3475 - Limb orthosis.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Limb orthosis. 890.3475 Section 890.3475 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3475 Limb orthosis. (a) Identification...

21 CFR 890.3475 - Limb orthosis.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Limb orthosis. 890.3475 Section 890.3475 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3475 Limb orthosis. (a) Identification...

Chronic Ankle Instability and Neural Excitability of the Lower Extremity.

PubMed

McLeod, Michelle M; Gribble, Phillip A; Pietrosimone, Brian G

2015-08-01

Neuromuscular dysfunction of the leg and thigh musculature, including decreased strength and postural control, is common in patients with chronic ankle instability (CAI). Understanding how CAI affects specific neural pathways may provide valuable information for targeted therapies. To investigate differences in spinal reflexive and corticospinal excitability of the fibularis longus and vastus medialis between limbs in patients with unilateral CAI and between CAI patients and participants serving as healthy controls. Case-control study. Research laboratory. A total of 56 participants volunteered, and complete data for 21 CAI patients (9 men, 12 women; age = 20.81 ± 1.63 years, height = 171.57 ± 11.44 cm, mass = 68.84 ± 11.93 kg) and 24 healthy participants serving as controls (7 men, 17 women; age = 22.54 ± 2.92 years, height = 172.35 ± 10.85 cm, mass = 69.15 ± 12.30 kg) were included in the final analyses. Control participants were matched to CAI patients on sex, age, and limb dominance. We assigned "involved" limbs, which corresponded with the involved limbs of the CAI patients, to control participants. Spinal reflexive excitability was assessed via the Hoffmann reflex and normalized to a maximal muscle response. Corticospinal excitability was assessed using transcranial magnetic stimulation. Active motor threshold (AMT) was defined as the lowest transcranial magnetic stimulation intensity required to elicit motor-evoked potentials equal to or greater than 100 μV in 5 of 10 consecutive stimuli. We obtained motor-evoked potentials (MEPs) at percentages ranging from 100% to 140% of AMT. Fibularis longus MEP amplitudes were greater in control participants than in CAI patients bilaterally at 100% AMT (control involved limb: 0.023 ± 0.031; CAI involved limb: 0.014 ± 0.008; control uninvolved limb: 0.021 ± 0.022; CAI uninvolved limb: 0.015 ± 0.007; F1,41 = 4.551, P = .04) and 105% AMT (control involved limb: 0.029 ± 0.026; CAI involved limb: 0.021 ± 0.009; control uninvolved limb: 0.034 ± 0.037; CAI uninvolved limb: 0.023 ± 0.013; F1,35 = 4.782, P = .04). We observed no differences in fibularis longus MEP amplitudes greater than 110% AMT and no differences in vastus medialis corticospinal excitability (P > .05). We noted no differences in the Hoffmann reflex between groups for the vastus medialis (F1,37 = 0.103, P = .75) or the fibularis longus (F1,41 = 1.139, P = .29). Fibularis longus corticospinal excitability was greater in control participants than in CAI patients.

TES/Aura L2 Atmospheric Temperatures Limb V6 (TL2TLS)

Atmospheric Science Data Center

2018-03-01

TES/Aura L2 Atmospheric Temperatures Limb (TL2TLS) News:  TES News ... Level:  L2 Platform:  TES/Aura L2 Atmospheric Temperatures Spatial Coverage:  27 x 23 km Limb ... OPeNDAP Access: OPeNDAP Parameters:  Atmospheric Temperature Temperature Precision Vertical Resolution ...

TES/Aura L2 Atmospheric Temperatures Limb V6 (TL2ATMTL)

Atmospheric Science Data Center

2018-03-01

TES/Aura L2 Atmospheric Temperatures Limb (TL2ATMTL) News:  TES News ... Level:  L2 Platform:  TES/Aura L2 Atmospheric Temperatures Spatial Coverage:  27 x 23 km Limb ... OPeNDAP Access: OPeNDAP Parameters:  Atmospheric Temperature Temperature Precision Vertical Resolution ...

TES/Aura L3 Atmospheric Temperatures Daily V4 (TL3ATD)

Atmospheric Science Data Center

2018-05-09

... Platform:  TES Aura L1B Nadir/Limb Spatial Coverage:  5.3 x 8.5 km nadir 37 x 23 km limb Spatial ... 0.5 x 5 km nadir 2.3 x 23 km limb Temporal Coverage:  08/22/2004 - present Temporal Resolution:  ...

Posttraumatic Oedema in Lower Limbs. Advances in Understanding Etiopathogenesis and Treatment. Review Article.

PubMed

Waśko, Marcin K; Langner, Maciej; Pomianowski, Stanisław

2016-11-30

Mechanical injury to soft tissues and bones of the lower limbs may be complicated by thrombosis and oedema. Treatment of posttraumatic oedema in the lower limbs can be difficult and protracted and rarely leads to complete recovery. The pathogenesis of posttraumatic oedema has not been fully elucidated. This paper presents the aetiopathogenesis of posttraumatic oedema in the lower limbs and a review of relevant literature in English and Polish of the last 5 years, describing therapy outcomes and potential perspectives for develop ment.

Clinical studies on teenage Brazilian victims of thalidomide.

PubMed

Schmidt, M; Salzano, F M

1983-07-01

Ninety-three Brazilian teenagers with thalidomide embryopathy were studied. The pattern of distribution of their most significant defect was: upper limbs, 66; lower limbs, 8; all four limbs, 12; head, 7. Only 10 individuals presented the major defect unilaterally. In 30 of 83 with bilateral defects there were differences in severity between the two sides. Of the 31 patients whose spines had been X-rayed, 16 showed defects, the most common being spina bifida occulta at S1. Gynecomasty was found in three of the patients having major upper limb defects.

Limb replantation with two robots: a feasibility study in a pig model.

PubMed

Taleb, Chihab; Nectoux, Eric; Liverneaux, Philippe

2009-01-01

The aim of this study is to assess the feasibility of limb replantations and transplantations by telesurgery. The material consisted in a large white pig and two surgical robots (DaVinciS telemanipulators). The procedure consisted in a trans-humeral cross-section of the left thoracic limb, which was secondarily replanted. Results showed good vascular permeability, while the operator's physiological tremor was suppressed. Our results seem to demonstrate that telesurgery could improve limb replantation and transplantation management, especially regarding operating gesture precision. (c) 2009 Wiley-Liss, Inc.

Effect of limb regeneration on size increase at molt of the shore crabs Hemigrapsus oregonensis and Pachygrapsus crassipes.

PubMed

Kuris, A M; Mager, M

1975-09-01

Size increase at molt is reduced following multiple limb regeneration in the shore crabs, Hemigrapsus oregonensis and Pachygrapsus crassipes. Limb loss per se does not influence postmolt size. Effect of increasing number of regenerating limbs is additive. Postmolt size is programmed early in the premolt period of the preceding instar and is probably not readily influenced by water uptake mechanics at ecdysis. A simple model for growth, molting, and regeneration in heavily calcified Crustacea is developed from the viewpoint of adaptive strategies and energetic considerations.

Limb apraxia in aphasic patients.

PubMed

Ortiz, Karin Zazo; Mantovani-Nagaoka, Joana

2017-11-01

Limb apraxia is usually associated with left cerebral hemisphere damage, with numerous case studies involving aphasic patients. The aim of this study was to verify the occurrence of limb apraxia in aphasic patients and analyze its nature. This study involved 44 healthy volunteers and 28 aphasic patients matched for age and education. AH participants were assessed using a limb apraxia battery comprising subtests evaluating lexical-semantic aspects related to the comprehension/production of gestures as well as motor movements. Aphasics had worse performances on many tasks related to conceptual components of gestures. The difficulty found on the imitation of dynamic gesture tasks also indicated that there were specific motor difficulties in gesture planning. These results reinforce the importance of conducting limb apraxia assessment in aphasic patients and also highlight pantomime difficulties as a good predictor for semantic disturbances.

Development of a 3-D Rehabilitation System for Upper Limbs Using ER Actuators in a Nedo Project

NASA Astrophysics Data System (ADS)

Furusho, Junji; Koyanagi, Ken'ichi; Nakanishi, Kazuhiko; Ryu, Ushio; Takenaka, Shigekazu; Inoue, Akio; Domen, Kazuhisa; Miyakoshi, Koichi

New training methods and exercises for upper limbs rehabilitation are made possible by application of robotics and virtual reality technology. The technologies can also make quantitative evaluations and enhance the qualitative effect of training. We have joined a project managed by NEDO (New Energy and Industrial Technology Development Organization as a semi-governmental organization under the Ministry of Economy, Trade and Industry of Japan) 5-year Project, "Rehabilitation System for the Upper Limbs and Lower Limbs", and developed a 3-DOF exercise machine for upper limbs (EMUL) using ER actuators. In this paper, we also present the development of software for motion exercise trainings and some results of clinical evaluation. Moreover, it is discussed how ER actuators ensure the mechanical safety.

Development of limb volume measuring system

NASA Technical Reports Server (NTRS)

Bhagat, P. K.; Kadaba, P. K.

1983-01-01

The mechanisms underlying the reductions in orthostatic tolerance associated with weightlessness are not well established. Contradictory results from measurements of leg volume changes suggest that altered venomotor tone and reduced blood flow may not be the only contributors to orthostatic intolerance. It is felt that a more accurate limb volume system which is insensitive to environmental factors will aid in better quantification of the hemodynamics of the leg. Of the varous limb volume techniques presently available, the ultrasonic limb volume system has proven to be the best choice. The system as described herein is free from environmental effects, safe, simple to operate and causes negligible radio frequency interference problems. The segmental ultrasonic ultrasonic plethysmograph is expected to provide a better measurement of limb volume change since it is based on cross-sectional area measurements.

Limb Correction of Individual Infrared Channels Used in RGB Composite Products

NASA Technical Reports Server (NTRS)

Elmer, Nicholas J.; Berndt, Emily; Jedlovec, Gary J.; Lafontaine, Frank J.

2015-01-01

This study demonstrates that limb-cooling can be removed from infrared imagery using latitudinally and seasonally dependent limb correction coefficients, which account for an increasing optical path length as scan angle increases. Furthermore, limb-corrected RGB composites provide multiple advantages over uncorrected RGB composites, including increased confidence in the interpretation of RGB features, improved situation awareness for operational forecasters, seamless transition between overlaid RGB composites, easy comparison of RGB products from different sensors, and the availability of high quality proxy products for the GOES-R era, as demonstrated by the case examples presented in Section 3. This limb correction methodology can also be applied to additional infrared channels used to create other RGB products, including those created from other satellite sensors, such as Suomi NPP Visible Infrared Imaging Radiometer Suite (VIIRS).

[Analysis of the effect of detector's operating temperature on SNR in space-based remote sensor].

PubMed

Li, Zhan-feng; Wang, Shu-rong; Huang, Yu

2012-03-01

Limb viewing is a new viewing geometry for space-based atmospheric remote sensing, but the spectral radiance of atmosphere scattering reduces rapidly with limb height. So the signal-noise-ratio (SNR) is a key performance parameter of limb remote sensor. A SNR model varying with detector's temperature is proposed, based on analysis of spectral radiative transfer and noise' source in representative instruments. The SNR at limb height 70 km under space conditions was validated by simulation experiment on limb remote sensing spectrometer prototype. Theoretic analysis and experiment's results indicate congruously that when detector's temperature reduces to some extent, a maximum SNR will be reached. After considering the power consumption, thermal conductivity and other issues, optimal operating temperature of detector can be decided.

Five early accounts of phantom limb in context: Paré, Descartes, Lemos, Bell, and Mitchell.

PubMed

Finger, Stanley; Hustwit, Meredith P

2003-03-01

PHANTOM LIMB WAS described long before American physician and surgeon Silas Weir Mitchell coined the term and drew attention to the disorder in the 1860s. The early descriptions of Ambroise Paré, René Descartes, Aaron Lemos, Charles Bell, and then Mitchell of this strange consequence of amputation are presented in historical and cultural context. These five men described phantom limbs for various reasons. They also differed when it came to explaining and dealing with these illusory sensations. The rich history of phantom limbs can begin to be appreciated by viewing the contributions of these individuals in perspective and by realizing that their writings represent only a fraction of what was published about phantom limbs more than 130 years ago.

From LIMS to OMPS-LP: limb ozone observations for future reanalyses

NASA Astrophysics Data System (ADS)

Wargan, K.; Kramarova, N. A.; Remsberg, E. E.; Coy, L.; Harvey, L.; Livesey, N. J.; Pawson, S.

2017-12-01

High vertical resolution and accuracy of ozone data from satellite-borne limb sounders have made them an invaluable tool in scientific studies of the middle and upper atmosphere. However, it was not until recently that these measurements were successfully incorporated in atmospheric reanalyses: of the major multidecadal reanalyses only ECMWF's ERA-Interim/ERA5 and NASA's MERRA-2 use limb ozone data. Validation and comparison studies have demonstrated that the addition of observations from the Microwave Limb Sounder (MLS) on EOS Aura greatly improved the quality of ozone fields in MERRA-2 making these assimilated data sets useful for scientific research. In this presentation, we will show the results of test experiments assimilating retrieved ozone from the Limb Infrared Monitor of the Stratosphere (LIMS, 1978/1979) and Ozone Mapping Profiler Suite Limb Profiler (OMPS-LP, 2012 to present). Our approach builds on the established assimilation methodology used for MLS in MERRA-2 and, in the case of OMPS-LP, extends the excellent record of MLS ozone assimilation into the post-EOS era in Earth observations. We will show case studies, discuss comparisons of the new experiments with MERRA-2, strategies for bias correction and the potential for combined assimilation of multiple limb ozone data types in future reanalyses for studies of multidecadal stratospheric ozone changes including trends.

Reliability, agreement, and validity of digital weighing scale with MatScan in limb load measurement.

PubMed

Kumar, Senthil N S; Omar, Baharudin; Htwe, Ohnmar; Joseph, Leonard H; Krishnan, Jagannathan; Jafarzedah Esfehani, Ali; Min, Lee L

2014-01-01

Limb loading measurements serve as an objective evaluation of asymmetrical weight bearing in the lower limb. Digital weighing scales (DWSs) could be used in clinical settings for measurement of static limb loading. However, ambiguity exists whether limb loading measurements of DWSs are comparable with a standard tool such as MatScan. A cross-sectional study composed of 33 nondisabled participants was conducted to investigate the reliability, agreement, and validity of DWSs with MatScan in static standing. Amounts of weight distribution and plantar pressure on the individual lower limb were measured using two DWSs (A, B) and MatScan during eyes open (EO) and eyes closed (EC) conditions. The results showed that intra- and interrater reliability (3, 1) were excellent (0.94-0.97) within and between DWS A and B. Bland-Altman plot revealed good agreement between DWS and MatScan in EO and EC conditions. The area under the receiver operating characteristic curve was significant and identified as 0.68 (p = 0.01). The measurements obtained with DWSs are valid and in agreement with MatScan measurements. Hence, DWSs could be used interchangeably with MatScan and could provide clinicians an objective measurement of limb loading suitable for clinical settings.

Proximity to pollution sources and risk of amphibian limb malformation.

PubMed

Taylor, Brynn; Skelly, David; Demarchis, Livia K; Slade, Martin D; Galusha, Deron; Rabinowitz, Peter M

2005-11-01

The cause of limb deformities in wild amphibian populations remains unclear, even though the apparent increase in prevalence of this condition may have implications for human health. Few studies have simultaneously assessed the effect of multiple exposures on the risk of limb deformities. In a cross-sectional survey of 5,264 hylid and ranid metamorphs in 42 Vermont wetlands, we assessed independent risk factors for nontraumatic limb malformation. The rate of nontraumatic limb malformation varied by location from 0 to 10.2%. Analysis of a subsample did not demonstrate any evidence of infection with the parasite Ribeiroia. We used geographic information system (GIS) land-use/land-cover data to validate field observations of land use in the proximity of study wetlands. In a multiple logistic regression model that included land use as well as developmental stage, genus, and water-quality measures, proximity to agricultural land use was associated with an increased risk of limb malformation (odds ratio = 2.26; 95% confidence interval, 1.42-3.58; p < 0.001). The overall discriminant power of the statistical model was high (C = 0.79). These findings from one of the largest systematic surveys to date provide support for the role of chemical toxicants in the development of amphibian limb malformation and demonstrate the value of an epidemiologic approach to this problem.

Melorheostosis of Leri: report of a case in a young African.

PubMed

Adeyomoye, A A O; Awosanya, G O G; Arogundade, R A

2004-09-01

Melorheostosis of Leri is a non-familial condition of hyperostosis of the cortical bone that usually presents unilaterally in long bones of the upper and lower limbs, but may also present in vertebra, ribs, skull and jaw. The incidence of this disease is quite rare, only about 300 cases have been reported worldwide. We present a case, which may be the first documented case in sub-Saharan Africa. S.K. is a 14 year old male student who presented to the hospital with an 18 month history of persistent pain in the joints of the right upper limb and a limb length discrepancy since birth which has worsened with growth. Examination revealed generalised hypoplasia of the right upper limb with shortening of the limb and atrophy of the muscles, also hypoplasia and contracture of the thumb was observed. The radiographs of the limb showed multiple areas of dense hyperostosis and scleroderma, which showed a linear distribution along the radial half of the bones. In children presentation of melorheostosis, is more likely be as limb length discrepancy, deformity or joint contractures which may be seen before radiographic evidence of any bony changes. Improvement in imaging techniques will therefore result in early diagnosis and greater success with conservative management. Also the increased frequency of tumours necessitates long-term follow up. melorheostosis, scleroderma.

Amputation rehabilitation and prosthetic restoration. From surgery to community reintegration.

PubMed

Esquenazi, Alberto

The purpose of this review is to summarize the literature related to the advances that have taken place in the management and rehabilitation care of limb amputation. Prostheses for the lower and upper limb amputee have changed greatly over the past several years, with advances in components, socket fabrication and fitting techniques, suspension systems and sources of power and electronic controls. Higher levels of limb amputation can now be fitted with functional prostheses, which allow more patients to achieve independent life styles. This is of particular importance for the multi-limb amputee. The rehabilitation of more traditional lower limb levels of amputation have also greatly benefited from the technological advances including energy storing feet, electronic control hydraulic knees, ankle rotators and shock absorbers to mention a few. For the upper limb amputee, myoelectric and proportional controlled terminal devices and elbow joints are now used routinely in some rehabilitation facilities. Experimental prosthetic fitting techniques and devices such as the use of osseo-implantation for suspension of the prosthesis, tension control hands or electromagnetic fluids for knee movement control will also be briefly discussed in this paper. It is possible to conclude from this review that many advances have occurred that have greatly impacted the functional outcomes of patients with limb amputation.

Analysis of Msx1; Msx2 double mutants reveals multiple roles for Msx genes in limb development.

PubMed

Lallemand, Yvan; Nicola, Marie-Anne; Ramos, Casto; Bach, Antoine; Cloment, Cécile Saint; Robert, Benoît

2005-07-01

The homeobox-containing genes Msx1 and Msx2 are highly expressed in the limb field from the earliest stages of limb formation and, subsequently, in both the apical ectodermal ridge and underlying mesenchyme. However, mice homozygous for a null mutation in either Msx1 or Msx2 do not display abnormalities in limb development. By contrast, Msx1; Msx2 double mutants exhibit a severe limb phenotype. Our analysis indicates that these genes play a role in crucial processes during limb morphogenesis along all three axes. Double mutant limbs are shorter and lack anterior skeletal elements (radius/tibia, thumb/hallux). Gene expression analysis confirms that there is no formation of regions with anterior identity. This correlates with the absence of dorsoventral boundary specification in the anterior ectoderm, which precludes apical ectodermal ridge formation anteriorly. As a result, anterior mesenchyme is not maintained, leading to oligodactyly. Paradoxically, polydactyly is also frequent and appears to be associated with extended Fgf activity in the apical ectodermal ridge, which is maintained up to 14.5 dpc. This results in a major outgrowth of the mesenchyme anteriorly, which nevertheless maintains a posterior identity, and leads to formation of extra digits. These defects are interpreted in the context of an impairment of Bmp signalling.

Prx-1 expression in Xenopus laevis scarless skin-wound healing and its resemblance to epimorphic regeneration.

PubMed

Yokoyama, Hitoshi; Maruoka, Tamae; Aruga, Akio; Amano, Takanori; Ohgo, Shiro; Shiroishi, Toshihiko; Tamura, Koji

2011-12-01

Despite a strong clinical need for inducing scarless wound healing, the molecular factors required to accomplish it are unknown. Although skin-wound healing in adult mammals often results in scarring, some amphibians can regenerate injured body parts, even an amputated limb, without it. To understand the mechanisms of perfect skin-wound healing in regenerative tetrapods, we studied the healing process in young adult Xenopus "froglets" after experimental skin excision. We found that the excision wound healed completely in Xenopus froglets, without scarring. Mononuclear cells expressing a homeobox gene, prx1, accumulated under the new epidermis of skin wounds on the limb and trunk and at the regenerating limb. In transgenic Xenopus froglets expressing a reporter for the mouse prx1 limb-specific enhancer, activity was seen in the healing skin and in the regenerating limb. Comparable activity did not accompany skin-wound healing in adult mice. Our results suggest that scarless skin-wound healing may require activation of the prx1 limb enhancer, and competence to activate the enhancer is probably a prerequisite for epimorphic regeneration, such as limb regeneration. Finally, the induction of this prx1 enhancer activity may be useful as a reliable marker for therapeutically induced scarless wound healing in mammals.

Evaluation of Limb Load Asymmetry Using Two New Mathematical Models

PubMed Central

Kumar, Senthil NS; Omar, Baharudin; Joseph, Leonard H.; Htwe, Ohnmar; Jagannathan, K.; Hamdan, Nor M Y; Rajalakshmi, D.

2015-01-01

Quantitative measurement of limb loading is important in orthopedic and neurological rehabilitation. In current practice, mathematical models such as Symmetry index (SI), Symmetry ratio (SR), and Symmetry angle (SA) are used to quantify limb loading asymmetry. Literatures have identified certain limitations with the above mathematical models. Hence this study presents two new mathematical models Modified symmetry index (MSI) and Limb loading error (LLE) that would address these limitations. Furthermore, the current mathematical models were compared against the new model with the goal of achieving a better model. This study uses hypothetical data to simulate an algorithmic preliminary computational measure to perform with all numerical possibilities of even and uneven limb loading that can occur in human legs. Descriptive statistics are used to interpret the limb loading patterns: symmetry, asymmetry and maximum asymmetry. The five mathematical models were similar in analyzing symmetry between limbs. However, for asymmetry and maximum asymmetry data, the SA and SR values do not give any meaningful interpretation, and SI gives an inflated value. The MSI and LLE are direct, easy to interpret and identify the loading patterns with the side of asymmetry. The new models are notable as they quantify the amount and side of asymmetry under different loading patterns. PMID:25716372

Clinical correlates of between-limb synchronization of standing balance control and falls during inpatient stroke rehabilitation.

PubMed

Mansfield, Avril; Mochizuki, George; Inness, Elizabeth L; McIlroy, William E

2012-01-01

Stroke-related sensorimotor impairment potentially contributes to impaired balance. Balance measures that reveal underlying limb-specific control problems, such as a measure of the synchronization of both lower limbs to maintain standing balance, may be uniquely informative about poststroke balance control. This study aimed to determine the relationships between clinical measures of sensorimotor control, functional balance, and fall risk and between-limb synchronization of balance control. The authors conducted a retrospective chart review of 100 individuals with stroke admitted to inpatient rehabilitation. Force plate-based measures were obtained while standing on 2 force plates, including postural sway (root mean square of anteroposterior and mediolateral center of pressure [COP]), stance load asymmetry (percentage of body weight borne on the less-loaded limb), and between-limb synchronization (cross-correlation of the COP recordings under each foot). Clinical measures obtained were motor impairment (Chedoke-McMaster Stroke Assessment), plantar cutaneous sensation, functional balance (Berg Balance Scale), and falls experienced in rehabilitation. Synchronization was significantly related to motor impairment and prospective falls, even when controlling for other force plate-based measures of standing balance control (ie, postural sway and stance load symmetry). Between-limb COP synchronization for standing balance appears to be a uniquely important index of balance control, independent of postural sway and load symmetry during stance.

Modification of hemiplegic compensatory gait pattern by symmetry-based motion controller of HAL.

PubMed

Kawamoto, Hiroaki; Kadone, Hideki; Sakurai, Takeru; Sankai, Yoshiyuki

2015-01-01

As one of several characteristics of hemiplegic patients after stroke, compensatory gait caused by affected limb is often seen. The purpose of this research is to apply a symmetry-based controller of a wearable type lower limb robot, Hybrid Assistive Limb (HAL) to hemiplegic patients with compensatory gait, and to investigate improvement of gait symmetry. The controller is designed respectively for swing phase and support phase according to characteristics of hemiplegic gait pattern. The controller during swing phase stores the motion of the unaffected limb and then provides motion support on the affected limb during the subsequent swing using the stored pattern to realize symmetric gait based on spontaneous limb swing. Moreover, the controller during support phase provides motion to extend hip and knee joints to support wearer's body. Clinical tests were conducted in order to assess the modification of gait symmetry. Our case study involved participation of one chronic stroke patient who performs abnormally-compensatory gait for both of the affected and unaffected limbs. As a result, the patient's gait symmetry was improved by providing motion support during the swing phase on the affected side and motion constraint during the support phase on the unaffected side. The study showed promising basis for the effectiveness of the controller for the future clinical study.

Pattern of spread and prognosis in lower limb-onset ALS

PubMed Central

TURNER, MARTIN R.; BROCKINGTON, ALICE; SCABER, JAKUB; HOLLINGER, HANNAH; MARSDEN, RACHAEL; SHAW, PAMELA J.; TALBOT, KEVIN

2011-01-01

Our objective was to establish the pattern of spread in lower limb-onset ALS (contra- versus ipsi-lateral) and its contribution to prognosis within a multivariate model. Pattern of spread was established in 109 sporadic ALS patients with lower limb-onset, prospectively recorded in Oxford and Sheffield tertiary clinics from 2001 to 2008. Survival analysis was by univariate Kaplan-Meier log-rank and multivariate Cox proportional hazards. Variables studied were time to next limb progression, site of next progression, age at symptom onset, gender, diagnostic latency and use of riluzole. Initial progression was either to the contralateral leg (76%) or ipsilateral arm (24%). Factors independently affecting survival were time to next limb progression, age at symptom onset, and diagnostic latency. Time to progression as a prognostic factor was independent of initial direction of spread. In a regression analysis of the deceased, overall survival from symptom onset approximated to two years plus the time interval for initial spread. In conclusion, rate of progression in lower limb-onset ALS is not influenced by whether initial spread is to the contralateral limb or ipsilateral arm. The time interval to this initial spread is a powerful factor in predicting overall survival, and could be used to facilitate decision-making and effective care planning. PMID:20001488

A bioinformatics expert system linking functional data to anatomical outcomes in limb regeneration

PubMed Central

Lobo, Daniel; Feldman, Erica B.; Shah, Michelle; Malone, Taylor J.

2014-01-01

Abstract Amphibians and molting arthropods have the remarkable capacity to regenerate amputated limbs, as described by an extensive literature of experimental cuts, amputations, grafts, and molecular techniques. Despite a rich history of experimental effort, no comprehensive mechanistic model exists that can account for the pattern regulation observed in these experiments. While bioinformatics algorithms have revolutionized the study of signaling pathways, no such tools have heretofore been available to assist scientists in formulating testable models of large‐scale morphogenesis that match published data in the limb regeneration field. Major barriers to preventing an algorithmic approach are the lack of formal descriptions for experimental regenerative information and a repository to centralize storage and mining of functional data on limb regeneration. Establishing a new bioinformatics of shape would significantly accelerate the discovery of key insights into the mechanisms that implement complex regeneration. Here, we describe a novel mathematical ontology for limb regeneration to unambiguously encode phenotype, manipulation, and experiment data. Based on this formalism, we present the first centralized formal database of published limb regeneration experiments together with a user‐friendly expert system tool to facilitate its access and mining. These resources are freely available for the community and will assist both human biologists and artificial intelligence systems to discover testable, mechanistic models of limb regeneration. PMID:25729585

Resistance Training Reduces Force Tremor and Improves Manual Dexterity in Older Individuals With Essential Tremor.

PubMed

Kavanagh, Justin J; Wedderburn-Bisshop, Jacob; Keogh, Justin W L

2016-01-01

Although symptoms of Essential Tremor (ET) are typically controlled with medication, it is of interest to explore additional therapies to assist with functionality. The purpose of this study was to determine if a generalized upper limb resistance training (RT) program improves manual dexterity and reduces force tremor in older individuals with ET. Ten Essential Tremor and 9 controls were recruited into a dual group, pretest-posttest intervention study. Participants performed 6 weeks of upper-limb RT, and battery of manual dexterity and isometric force tremor assessments were performed before and after the RT to determine the benefits of the program. The six-week, high-load, RT program produced strength increases in each limb for the ET and healthy older group. These changes in strength aligned with improvements in manual dexterity and tremor-most notably for the ET group. The least affected limb and the most affected limb exhibited similar improvements in functional assessments of manual dexterity, whereas reductions in force tremor amplitude following the RT program were restricted to the most affected limb of the ET group. These findings suggest that generalized upper limb RT program has the potential to improve aspects of manual dexterity and reduce force tremor in older ET patients.

The Relative Contribution of Ankle Moment and Trailing Limb Angle to Propulsive Force during Gait

PubMed Central

Hsiao, HaoYuan; Knarr, Brian A.; Higginson, Jill S.; Binder-Macleod, Stuart A.

2014-01-01

A major factor for increasing walking speed is the ability to increase propulsive force. Although propulsive force has been shown to be related to ankle moment and trailing limb angle, the relative contribution of each factor to propulsive force has never been determined. The primary purpose of this study was to quantify the relative contribution of ankle moment and trailing limb angle to propulsive force for able-bodied individuals walking at different speeds. Twenty able-bodied individuals walked at their self-selected and 120% of self-selected walking speed on the treadmill. Kinematic data were collected using an 8-camera motion-capture system. A model describing the relationship between ankle moment, trailing limb angle and propulsive force was obtained through quasi-static analysis. Our main findings were that ankle moment and trailing limb angle each contributes linearly to propulsive force, and that the change in trailing limb angle contributes almost as twice as much as the change in ankle moment to the increase in propulsive force during speed modulation for able-bodied individuals. Able-bodied individuals preferentially modulate trailing limb angle more than ankle moment to increase propulsive force. Future work will determine if this control strategy can be applied to individuals poststroke. PMID:25498289

A pilot study to compare the cerebral hemodynamics between patients with obstructive sleep apnea syndrome (OSA) and periodic limb movement syndrome (PLMS) during nocturnal sleep with near-infrared spectroscopy (NIRS)

NASA Astrophysics Data System (ADS)

Zhang, Zhongxing; Schneider, Maja; Laures, Marco; Fritschi, Ursula; Hügli, Gordana; Lehner, Isabella; Qi, Ming; Khatami, Ramin

2014-03-01

Obstructive sleep apnea syndrome (OSA) and periodic limb movement in sleep syndrome (PLMS) are two common sleep disorders. Previous studies showed that OSA and PLMS share common features, such as increased cardio-vascular risk, both apnea events and limb movements occur periodically, they are usually associated with cortical arousals, and both of them can induce declines in peripheral oxygen saturation measured with pulse oximetry. However, the question whether apnea events and limb movements also show similar characteristics in cerebral hemodynamic and oxygenation has never been addressed. In this pilot study, we will first time compare the cerebral hemodynamic changes induced by apnea events and limb movements in patients with OSA (n=4) and PLMS (n=4) with NIRS. In patients with OSA, we found periodic oscillations in HbO2, HHb, and blood volume induced by apnea/hypopnea events, HbO2 and HHb showed reverse changing trends. By contrast, the periodic oscillations linked to limb movements were only found in HbO2 and blood volume in patients with PLMS. These findings of different cerebral hemodynamics patterns between apnea events and limb movements may indicate different regulations of nervous system between these two sleep disorders.

Recovery of peripheral muscle function from fatiguing exercise and daily physical activity level in patients with multiple sclerosis: a case-control study.

PubMed

Ickmans, Kelly; Simoens, Fauve; Nijs, Jo; Kos, Daphne; Cras, Patrick; Willekens, Barbara; Meeus, Mira

2014-07-01

Delayed recovery of muscle function following exercise has been demonstrated in the lower limbs of patients with multiple sclerosis (MS). However, studies examining this in the upper limbs are currently lacking. This study compared physical activity level (PAL) and recovery of upper limb muscle function following exercise between MS patients and healthy inactive controls. Furthermore, the relationship between PAL and muscle recovery was examined. PAL of 19 MS patients and 32 controls was measured using an accelerometer for 7 consecutive days. Afterwards, recovery of muscle function was assessed by performing a fatiguing upper limb exercise test with subsequent recovery measures. Muscle recovery of the upper limb muscles was similar in both groups. Average activity counts were significantly lower in MS patients than in the control group. MS patients spent significantly more time being sedentary and less time on activities of moderate intensity compared with the control group. No significant correlation between PAL and recovery of muscle function was found in MS patients. Recovery of upper limb muscle function following exercise is normal in MS patients. MS patients are less physically active than healthy inactive controls. PAL and recovery of upper limb muscle function appear unrelated in MS patients. Copyright © 2014 Elsevier B.V. All rights reserved.

How do sock ply changes affect residual-limb fluid volume in people with transtibial amputation?

PubMed

Sanders, Joan E; Harrison, Daniel S; Allyn, Katheryn J; Myers, Timothy R; Ciol, Marcia A; Tsai, Elaine C

2012-01-01

The purpose of this research was to investigate the influence of sock addition and removal on residual-limb fluid volume in people using prosthetic limbs. We used bioimpedance analysis to measure residual-limb extracellular fluid volume on 28 transtibial amputee subjects during 30 min test sessions. Upon addition of a one-ply polyester sock, residual-limb fluid volume changes ranged from -4.0% to 0.8% (mean -0.9 +/- 1.3%) of the initial limb fluid volume. Changes for sock removal ranged from -1.2% to 2.8% (mean 0.5 +/- 0.8%). Subjects who reduced in fluid volume with both addition and removal of a sock and subjects with high positive ratios between the fluid-volume loss upon sock addition and gain upon sock removal (high add/remove [AR] ratios) tended to have arterial disease, were obese, and were smokers. Subjects with low positive AR ratios, subjects who increased in fluid volume both with sock addition and removal, and a single subject who increased in fluid volume with sock addition and decreased with sock removal tended to be nonsmokers and either individuals in good health without complications or individuals without arterial problems. Results are relevant for the anticipation of limb volume changes during prosthetic fitting and toward the design of adjustable-socket technologies.

Outcome Assessments of Patients with Posttraumatic “Ultra-Time Vascular Injuries” of the Extremities

PubMed Central

Sun, Yi-Feng; Fang, Qiong-Xuan; Zhan, Hong-Yan; Wang, Fan; Cao, Wei; Zhao, Gang

2015-01-01

The management of posttraumatic vascular injury that presents after 8 h, or “ultra-time vascular injury”, is daunting, and inciting recognition of this injury is vital. We retrospectively analyzed 29 patients with ultra-time vascular injuries to determine the patients’ demographic characteristics and identify the determinants for amputation and disability. The age distribution of the high-risk population was from 18 years to 40 years, which indicated that these patients had plenty of productive life remaining. Injuries to the lower limbs (79.31%) were over four times more common than injuries to the upper limbs (17.24%), and open and blunt injuries occurred most commonly. The overall rate of limb salvage was 82.76% (24/29) and limb function is excellent in 45.83% (11/24) of the patients. The remaining patients experienced different degrees of disability in their limbs, which was determined by the anatomic location of the injury, and the presence of a combined arterial and venous injury, nerve injury, and complex soft tissue injury, as well as the occurrence of compartment syndrome. Hence, we recommend limb-salvage treatment for patients with traumatic ultra-time vascular injuries, particularly for those aged between 18 years and 40 years. Furthermore, we encourage the development of limb-salvage techniques for ultra-time vascular injuries. PMID:26639214

Blood temperature and perfusion to exercising and non-exercising human limbs.

PubMed

González-Alonso, José; Calbet, José A L; Boushel, Robert; Helge, Jørn W; Søndergaard, Hans; Munch-Andersen, Thor; van Hall, Gerrit; Mortensen, Stefan P; Secher, Niels H

2015-10-01

What is the central question of this study? Temperature-sensitive mechanisms are thought to contribute to blood-flow regulation, but the relationship between exercising and non-exercising limb perfusion and blood temperature is not established. What is the main finding and its importance? The close coupling among perfusion, blood temperature and aerobic metabolism in exercising and non-exercising extremities across different exercise modalities and activity levels and the tight association between limb vasodilatation and increases in plasma ATP suggest that both temperature- and metabolism-sensitive mechanisms are important for the control of human limb perfusion, possibly by activating ATP release from the erythrocytes. Temperature-sensitive mechanisms may contribute to blood-flow regulation, but the influence of temperature on perfusion to exercising and non-exercising human limbs is not established. Blood temperature (TB ), blood flow and oxygen uptake (V̇O2) in the legs and arms were measured in 16 healthy humans during 90 min of leg and arm exercise and during exhaustive incremental leg or arm exercise. During prolonged exercise, leg blood flow (LBF) was fourfold higher than arm blood flow (ABF) in association with higher TB and limb V̇O2. Leg and arm vascular conductance during exercise compared with rest was related closely to TB (r(2) = 0.91; P < 0.05), plasma ATP (r(2) = 0.94; P < 0.05) and limb V̇O2 (r(2) = 0.99; P < 0.05). During incremental leg exercise, LBF increased in association with elevations in TB and limb V̇O2, whereas ABF, arm TB and V̇O2 remained largely unchanged. During incremental arm exercise, both ABF and LBF increased in relationship to similar increases in V̇O2. In 12 trained males, increases in femoral TB and LBF during incremental leg exercise were mirrored by similar pulmonary artery TB and cardiac output dynamics, suggesting that processes in active limbs dominate central temperature and perfusion responses. The present data reveal a close coupling among perfusion, TB and aerobic metabolism in exercising and non-exercising extremities and a tight association between limb vasodilatation and increases in plasma ATP. These findings suggest that temperature and V̇O2 contribute to the regulation of limb perfusion through control of intravascular ATP. © 2015 The Authors Experimental Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.

Blood temperature and perfusion to exercising and non‐exercising human limbs

PubMed Central

Calbet, José A. L.; Boushel, Robert; Helge, Jørn W.; Søndergaard, Hans; Munch‐Andersen, Thor; van Hall, Gerrit; Mortensen, Stefan P.; Secher, Niels H.

2015-01-01

New Findings What is the central question of this study? Temperature‐sensitive mechanisms are thought to contribute to blood‐flow regulation, but the relationship between exercising and non‐exercising limb perfusion and blood temperature is not established. What is the main finding and its importance? The close coupling among perfusion, blood temperature and aerobic metabolism in exercising and non‐exercising extremities across different exercise modalities and activity levels and the tight association between limb vasodilatation and increases in plasma ATP suggest that both temperature‐ and metabolism‐sensitive mechanisms are important for the control of human limb perfusion, possibly by activating ATP release from the erythrocytes. Temperature‐sensitive mechanisms may contribute to blood‐flow regulation, but the influence of temperature on perfusion to exercising and non‐exercising human limbs is not established. Blood temperature (T B), blood flow and oxygen uptake (V˙O2) in the legs and arms were measured in 16 healthy humans during 90 min of leg and arm exercise and during exhaustive incremental leg or arm exercise. During prolonged exercise, leg blood flow (LBF) was fourfold higher than arm blood flow (ABF) in association with higher T B and limb V˙O2. Leg and arm vascular conductance during exercise compared with rest was related closely to T B (r 2 = 0.91; P < 0.05), plasma ATP (r 2 = 0.94; P < 0.05) and limb V˙O2 (r 2 = 0.99; P < 0.05). During incremental leg exercise, LBF increased in association with elevations in T B and limb V˙O2, whereas ABF, arm T B and V˙O2 remained largely unchanged. During incremental arm exercise, both ABF and LBF increased in relationship to similar increases in V˙O2. In 12 trained males, increases in femoral T B and LBF during incremental leg exercise were mirrored by similar pulmonary artery T B and cardiac output dynamics, suggesting that processes in active limbs dominate central temperature and perfusion responses. The present data reveal a close coupling among perfusion, T B and aerobic metabolism in exercising and non‐exercising extremities and a tight association between limb vasodilatation and increases in plasma ATP. These findings suggest that temperature and V˙O2 contribute to the regulation of limb perfusion through control of intravascular ATP. PMID:26268717

Second-Generation Six-Limbed Experimental Robot

NASA Technical Reports Server (NTRS)

Kennedy, Brett; Okon, Avi; Aghazarian, Hrand; Robinson, Matthew; Garrett, Michael; Magnone, Lee

2004-01-01

The figure shows the LEMUR II - the second generation of the Limbed Excursion Mechanical Utility Robot (LEMUR), which was described in "Six-Legged Experimental Robot" (NPO-20897), NASA Tech Briefs, Vol. 25, No. 12 (December 2001), page 58. The LEMUR II incorporates a number of improvements, including new features, that extend its capabilities beyond those of its predecessor, which is now denoted the LEMUR I. To recapitulate: the LEMUR I was a six-limbed robot for demonstrating robotic capabilities for assembly, maintenance, and inspection. The LEMUR I was designed to be capable of walking autonomously along a truss structure toward a mechanical assembly at a prescribed location and to perform other operations. The LEMUR I was equipped with stereoscopic video cameras and image-data-processing circuitry for navigation and mechanical operations. It was also equipped with a wireless modem, through which it could be commanded remotely. Upon arrival at a mechanical assembly, the LEMUR I would perform simple mechanical operations with one or both of its front limbs. It could also transmit images to a host computer. Each of the six limbs of the LEMUR I was operated independently. Each of the four rear limbs had three degrees of freedom (DOFs), while each of the front two limbs had four DOFs. The front two limbs were designed to hold, operate, and/or be integrated with tools. The LEMUR I included an onboard computer equipped with an assortment of digital control circuits, digital input/output circuits, analog-to-digital converters for input, and digital-to-analog (D/A) converters for output. Feedback from optical encoders in the limb actuators was utilized for closed-loop microcomputer control of the positions and velocities of the actuators. The LEMUR II incorporates the following improvements over the LEMUR I: a) The drive trains for the joints of the LEMUR II are more sophisticated, providing greater torque and accuracy. b) The six limbs are arranged symmetrically about a hexagonal body platform instead of in straight lines along the sides. This symmetrical arrangement is more conducive to omnidirectional movement in a plane. c) The number of degrees of freedom of each of the rear four limbs has been increased by one. Now, every limb has four degrees of freedom: three at the hip (or shoulder, depending on one s perspective) and one at the knee (or elbow, depending on one s perspective). d) Now every limb (instead of only the two front limbs) can perform operations. For this purpose, each limb is tipped with an improved quick-release mechanism for swapping of end-effector tools. e) New end-effector tools have been developed. These include an instrumented rotary driver that accepts all tool bits that have 0.125-in. (3.175-mm)-diameter shanks, a charge-coupled-device video camera, a super bright light-emitting diode for illuminating the work area of the robot, and a generic collet tool that can be quickly and inexpensively modified to accept any cylindrical object up to 0.5 in. (12.7 mm) in diameter. f) The stereoscopic cameras are mounted on a carriage that moves along a circular track, thereby providing for omnidirectional machine vision. g) The control software has been augmented with software that implements innovations reported in two prior NASA Tech Briefs articles: the HIPS algorithm ["Hybrid Image-Plane/Stereo Manipulation" (NPO-30492), Vol. 28, No. 7 (July 2004), page 55] and the CAMPOUT architecture ["An Architecture for Controlling Multiple Robots" (NPO-30345), Vol. 28, No. 10 (October 2004), page 65].

Propulsive forces of mudskipper fins and salamander limbs during terrestrial locomotion: implications for the invasion of land.

PubMed

Kawano, Sandy M; Blob, Richard W

2013-08-01

The invasion of land was a pivotal event in vertebrate evolution that was associated with major appendicular modifications. Although fossils indicate that the evolution of fundamentally limb-like appendages likely occurred in aquatic environments, the functional consequences of using early digited limbs, rather than fins, for terrestrial propulsion have had little empirical investigation. Paleontological and experimental analyses both have led to the proposal of an early origin of "hind limb-driven" locomotion among tetrapods or their ancestors. However, the retention of a pectoral appendage that had already developed terrestrial adaptations has been proposed for some taxa, and few data are available from extant functional models that can provide a foundation for evaluating the relative contributions of pectoral and pelvic appendages to terrestrial support among early stem tetrapods. To examine these aspects of vertebrate locomotor evolution during the invasion of land, we measured three-dimensional ground reaction forces (GRFs) produced by isolated pectoral fins of mudskipper fishes (Periophthalmus barbarus) during terrestrial crutching, and compared these to isolated walking footfalls by the forelimbs and hind limbs of tiger salamanders (Ambystoma tigrinum), a species with subequally-sized limbs that facilitate comparisons to early tetrapods. Pectoral appendages of salamanders and mudskippers exhibited numerous differences in GRFs. Compared with salamander forelimbs, isolated fins of mudskippers bear lower vertical magnitudes of GRFs (as a proportion of body weight), and had GRFs that were oriented more medially. Comparing the salamanders' forelimbs and hind limbs, although the peak net GRF occurs later in stance for the forelimb, both limbs experience nearly identical mediolateral and vertical components of GRF, suggesting comparable contributions to support. Thus, forelimbs could also have played a significant locomotor role among basal tetrapods that had limbs of sub-equal size. However, the salamander hind limb and mudskipper pectoral fin had a greater acceleratory role than did the salamander forelimb. Together, data from these extant taxa help to clarify how structural change may have influenced locomotor function through the evolutionary invasion of land by vertebrates.

RETURN TO RUNNING FOLLOWING A KNEE DISARTICULATION AMPUTATION: A CASE REPORT

PubMed Central

Diebal-Lee, Angela R.; Kuenzi, Robert S.; Rábago, Christopher A.

2017-01-01

Background and Purpose The evolution of running-specific prostheses has empowered athletes with lower extremity amputations to run farther and faster than previously thought possible; but running with proper mechanics is still paramount to an injury-free, active lifestyle. The purpose of this case report was to describe the successful alteration of intact limb mechanics from a Rearfoot Striking (RFS) to a Non-Rearfoot Striking (NRFS) pattern in an individual with a knee disarticulation amputation, the associated reduction in Average Vertical Loading Rate (AVLR), and the improvement in functional performance following the intervention. Case description A 30 year-old male with a traumatic right knee disarticulation amputation reported complaints of residual limb pain with running distances greater than 5 km, limiting his ability to train toward his goal of participating in triathlons. Qualitative assessment of his running mechanics revealed a RFS pattern with his intact limb and a NRFS pattern with his prosthetic limb. A full body kinematic and kinetic running analysis using 3D motion capture and force plates was performed. The average intact limb loading rate was four-times greater (112 body weights/s) than in his prosthetic limb which predisposed him to possible injury. He underwent a three week running intervention with a certified running specialist to learn a NRFS pattern with his intact limb. Outcomes Immediately following the running intervention, he was able to run distances of over 10 km without pain. On a two-mile fitness test, he decreased his run time from 19:54 min to 15:14 min. Additionally, the intact limb loading rate was dramatically reduced to 27 body weights/s, nearly identical to the prosthetic limb (24 body weights/s). Discussion This case report outlines a detailed return to run program that targets proprioceptive and neuromuscular components, injury prevention, and specificity of training strategies. The outcomes of this case report are promising as they may spur additional research toward understanding how to eliminate potential injury risk factors associated with running after limb loss. Level of Evidence 4 PMID:28900572

Absence of the genicular arterial anastomosis as generally depicted in textbooks

PubMed Central

Sabalbal, M; Johnson, M

2013-01-01

Introduction Textbook representations of the genicular arterial anastomosis show a large direct communication between the descending branch of the lateral circumflex femoral artery (DBLCFA) and a genicular branch of the popliteal artery but this is not compatible with clinical experience. The aim of this study was to determine whether the arterial anastomosis at the knee is sufficient, in the event of traumatic disruption of the superficial femoral artery, to infuse protective agents or to place a stent to restore flow to the lower leg. Methods Dissection of ten cadaveric lower limbs was performed to photograph the arterial anatomy from the inguinal ligament to the tibial tubercle. Anastomosis with branches of the popliteal artery was classified as: ‘direct communication’, ‘approaching communication’ or ‘no evident communication’. Results A constant descending artery in the lateral thigh (LDAT) was found to have five types of origin: Type 1 (2/10 limbs) involved the lateral circumflex femoral branch of the femoral artery, Type 2 (3/10 limbs) the lateral circumflex femoral branch of the profunda femoris artery, Type 3 (1/10 limbs) the femoral artery, Type 4 (3/10 limbs) the superficial femoral artery and Type 5 (2/10 limbs) the profunda femoris artery. In one limb, there were two descending arteries (Types 4 and 5). Collateral circulation at the knee was also variable: direct communicating vessels (3/10 limbs); approaching vessels with possible communication via capillaries (5/10 limbs); no evident communication (2/10 limbs). Communicating vessels, if present, are too small to provide immediate collateral circulation. Conclusions Modern representations of the genicular arterial anastomosis are inaccurate, derived commonly from an idealised image that first appeared Gray’s Anatomy in 1910. The afferent vessel is not the DBLCFA. The majority of subjects have the potential to recruit collateral circulation via the LDAT following gradual obstruction to normal arterial flow, which may be important if the LDAT is removed for bypass or flap surgery. A direct communication is rarely present and is never as robust as generally depicted in textbooks. PMID:24025288

Genetic regulation of canine skeletal traits: trade-offs between the hind limbs and forelimbs in the fox and dog

PubMed Central

Kharlamova, Anastasia V.; Trut, Lyudmila N.; Carrier, David R.; Chase, Kevin; Lark, Karl G.

2008-01-01

Synopsis Genetic variation in functionally integrated skeletal traits can be maintained over 10 million years despite bottlenecks and stringent selection. Here, we describe an analysis of the genetic architecture of the canid axial skeleton using populations of the Portuguese Water Dog Canis familiaris) and silver fox (Vulpes vulpes). Twenty-one skeletal metrics taken from radiographs of the forelimbs and hind limbs of the fox and dog were used to construct separate anatomical principal component (PC) matrices of the two species. In both species, 15 of the 21 PCs exhibited significant heritability, ranging from 25% to 70%. The second PC, in both species, represents a trade-off in which limb-bone width is inversely correlated with limb-bone length. PC2 accounts for approximately 15% of the observed skeletal variation, ~30% of the variation in shape. Many of the other significant PCs affect very small amounts of variation (e.g., 0.2–2%) along trade-off axes that partition function between the forelimbs and hind limbs. These PCs represent shape axes in which an increase in size of an element of the forelimb is associated with a decrease in size of an element of the hind limb and vice versa. In most cases, these trade-offs are heritable in both species and genetic loci have been identified in the Portuguese Water Dog for many of these. These PCs, present in both the dog and the fox, include ones that affect lengths of the forelimb versus the hind limb, length of the forefoot versus that of the hind foot, muscle moment (i.e., lever) arms of the forelimb versus hind limb, and cortical thickness of the bones of the forelimb versus hind limb. These inverse relationships suggest that genetic regulation of the axial skeleton results, in part, from the action of genes that influence suites of functionally integrated traits. Their presence in both dogs and foxes suggests that the genes controlling the regulation of these PCs of the forelimb versus hind limb may be found in other tetrapod taxa. PMID:18458753

Effect of coordinate frame compatibility on the transfer of implicit and explicit learning across limbs

PubMed Central

Carroll, Timothy J.

2016-01-01

Insights into the neural representation of motor learning can be obtained by investigating how learning transfers to novel task conditions. We recently demonstrated that visuomotor rotation learning transferred strongly between left and right limbs when the task was performed in a sagittal workspace, which afforded a consistent remapping for the two limbs in both extrinsic and joint-based coordinates. In contrast, transfer was absent when performed in horizontal workspace, where the extrinsically defined perturbation required conflicting joint-based remapping for the left and right limbs. Because visuomotor learning is thought to be supported by both implicit and explicit forms of learning, however, it is unclear to what extent these distinct forms of learning contribute to interlimb transfer. In this study, we assessed the degree to which interlimb transfer, following visuomotor rotation training, reflects explicit vs. implicit learning by obtaining verbal reports of participants' aiming direction before each movement. We also determined the extent to which these distinct components of learning are constrained by the compatibility of coordinate systems by comparing transfer between groups of participants who reached to targets arranged in the horizontal and sagittal planes. Both sagittal and horizontal conditions displayed complete transfer of explicit learning to the untrained limb. In contrast, transfer of implicit learning was incomplete, but the sagittal condition showed greater transfer than the horizontal condition. These findings suggest that explicit strategies developed with one limb can be fully implemented in the opposite limb, whereas implicit transfer depends on the degree to which new sensorimotor maps are spatially compatible for the two limbs. PMID:27334955

Effect of coordinate frame compatibility on the transfer of implicit and explicit learning across limbs.

PubMed

Poh, Eugene; Carroll, Timothy J; Taylor, Jordan A

2016-09-01

Insights into the neural representation of motor learning can be obtained by investigating how learning transfers to novel task conditions. We recently demonstrated that visuomotor rotation learning transferred strongly between left and right limbs when the task was performed in a sagittal workspace, which afforded a consistent remapping for the two limbs in both extrinsic and joint-based coordinates. In contrast, transfer was absent when performed in horizontal workspace, where the extrinsically defined perturbation required conflicting joint-based remapping for the left and right limbs. Because visuomotor learning is thought to be supported by both implicit and explicit forms of learning, however, it is unclear to what extent these distinct forms of learning contribute to interlimb transfer. In this study, we assessed the degree to which interlimb transfer, following visuomotor rotation training, reflects explicit vs. implicit learning by obtaining verbal reports of participants' aiming direction before each movement. We also determined the extent to which these distinct components of learning are constrained by the compatibility of coordinate systems by comparing transfer between groups of participants who reached to targets arranged in the horizontal and sagittal planes. Both sagittal and horizontal conditions displayed complete transfer of explicit learning to the untrained limb. In contrast, transfer of implicit learning was incomplete, but the sagittal condition showed greater transfer than the horizontal condition. These findings suggest that explicit strategies developed with one limb can be fully implemented in the opposite limb, whereas implicit transfer depends on the degree to which new sensorimotor maps are spatially compatible for the two limbs. Copyright © 2016 the American Physiological Society.

Effects of Acute Alcohol Tolerance on Perceptions of Danger and Willingness to Drive after Drinking

PubMed Central

Amlung, Michael T.; Morris, David H.; McCarthy, Denis M.

2014-01-01

Rationale Drinking and driving is associated with elevated rates of motor vehicle accidents and fatalities. Previous research suggests that alcohol impairs judgments about the dangers of risky behaviors; however, how alcohol affects driving-related judgments is less clear. Impairments have also been shown to differ across limbs of the blood alcohol concentration (BAC) curve, which is known as acute tolerance. Objectives Examine whether perceptions about the dangerousness of driving after drinking and willingness to drive differed across ascending and descending limbs of the BAC curve. Test whether reductions in perceived danger were associated with willingness to drive on the descending limb. Methods Fifty-six participants were randomly assigned to receive either a moderate dose of alcohol (peak BAC = 0.10 g%) or placebo. We assessed perceived dangerousness and willingness to drive at matched BACs (~0.067-0.068 g%) on the ascending and descending limbs. Results Both perceived danger and willingness to drive showed acute tolerance in the alcohol group. Participants judged driving to be significantly less dangerous and were more willing to drive on the descending limb compared to the ascending limb. The magnitude of change in perceived danger significantly predicted willingness to drive on the descending limb. Conclusions Decreased impairment associated with acute tolerance may lead individuals to underestimate the dangerousness of driving after drinking and in turn make poor decisions regarding driving. This study further emphasizes the descending limb as a period of increased risk and offers support for enhancing prevention efforts by targeting drivers at declining BAC levels. PMID:24752657

Effects of acute alcohol tolerance on perceptions of danger and willingness to drive after drinking.

PubMed

Amlung, Michael T; Morris, David H; McCarthy, Denis M

2014-11-01

Drinking and driving is associated with elevated rates of motor vehicle accidents and fatalities. Previous research suggests that alcohol impairs judgments about the dangers of risky behaviors; however, how alcohol affects driving-related judgments is less clear. Impairments have also been shown to differ across limbs of the blood alcohol concentration (BAC) curve, which is known as acute tolerance. The objectives of this study were to examine whether perceptions about the dangerousness of driving after drinking and willingness to drive differed across the ascending and descending limbs of the BAC curve and to test whether reductions in perceived danger were associated with willingness to drive on the descending limb. Fifty-six participants were randomly assigned to receive either a moderate dose of alcohol (peak BAC = 0.10 g%) or placebo. We assessed perceived dangerousness and willingness to drive at matched BACs (~0.067-0.068 g%) on the ascending and descending limbs. Both perceived danger and willingness to drive showed acute tolerance in the alcohol group. Participants judged driving to be significantly less dangerous and were more willing to drive on the descending limb compared to the ascending limb. The magnitude of change in perceived danger significantly predicted willingness to drive on the descending limb. Decreased impairment associated with acute tolerance may lead individuals to underestimate the dangerousness of driving after drinking and in turn make poor decisions regarding driving. This study further emphasizes the descending limb as a period of increased risk and offers support for enhancing prevention efforts by targeting drivers at declining BAC levels.

Body proportions in ancient Andeans from high and low altitudes.

PubMed

Weinstein, Karen J

2005-11-01

Living human populations from high altitudes in the Andes exhibit relatively short limbs compared with neighboring groups from lower elevations as adaptations to cold climates characteristic of high-altitude environments. This study compares relative limb lengths and proportions in pre-Contact human skeletons from different altitudes to test whether ecogeographic variation also existed in Andean prehistory. Maximum lengths of the humerus, radius, femur, and tibia, and femoral head breadth are measured in sex-specific groups of adult human skeletons (N = 346) from the central (n = 80) and the south-central (n = 123) Andean coasts, the Atacama Desert at 2,500 m (n = 102), and the southern Peruvian highlands at 2,000-3,800 m (n = 41). To test whether limb lengths vary with altitude, comparisons are made of intralimb proportions, limb lengths against body mass estimates derived from published equations, limb lengths against the geometric mean of all measurements, and principal component analysis. Intralimb proportions do not statistically differ between coastal groups and those from the Atacama Desert, whereas intralimb proportions are significantly shorter in the Peruvian highland sample. Overall body size and limb lengths relative to body size vary along an altitudinal gradient, with larger individuals from coastal environments and smaller individuals with relatively longer limbs for their size from higher elevations. Ecogeographic variation in relation to climate explains the variation in intralimb proportions, and dietary variation may explain the altitudinal cline in body size and limb lengths relative to body size. The potential effects of gene flow on variation in body proportions in Andean prehistory are also explored. Copyright 2005 Wiley-Liss, Inc

Survival outcomes of pediatric osteosarcoma and Ewing's sarcoma: a comparison of surgery type within the SEER database, 1988-2007.

PubMed

Schrager, Justin; Patzer, Rachel E; Mink, Pamela J; Ward, Kevin C; Goodman, Michael

2011-01-01

Survival following diagnosis of pediatric Ewing's sarcoma or osteosarcoma is increasing in the United States, but whether survival differs between patients who receive limb salvage surgery compared to amputation has not been evaluated in nationally representative, population-based data. Multivariable-adjusted survival was calculated using Cox regression models among surgically treated pediatric (age <20) osteosarcoma and Ewing's sarcoma patients with bone cancer of the limbs or joints reported to the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program during 1988-2007. Over half (66.3%) of the 890 osteosarcoma patients underwent limb salvage surgery. Five-year overall survival among patients who received limb salvage was 72.7% for osteosarcoma patients and 71.8% for Ewing's sarcoma patients. Among patients who received amputation, 5-year survival was 60.1% for osteosarcoma and 63.1% for Ewing's sarcoma patients. After multivariable adjustment, the mortality was 35% greater for amputation vs limb salvage (HR=1.35, 95% CI: 1.05-1.75). Among 165 Ewing's sarcoma patients, 73.9% underwent limb salvage (vs amputation), and the adjusted mortality was higher for patients receiving amputation, although results were not statistically significant (HR=1.61, 95% CI: 0.80-3.21). Limb salvage surgery (vs amputation) is associated with longer survival among pediatric patients with bone cancer of the limbs or joints. Patient and physician characteristics and the effectiveness of neoadjuvant therapy may play a role in surgery choice, but we were unable to control for these factors.

Calculating regional tissue volume for hyperthermic isolated limb perfusion: Four methods compared.

PubMed

Cecchin, D; Negri, A; Frigo, A C; Bui, F; Zucchetta, P; Bodanza, V; Gregianin, M; Campana, L G; Rossi, C R; Rastrelli, M

2016-12-01

Hyperthermic isolated limb perfusion (HILP) can be performed as an alternative to amputation for soft tissue sarcomas and melanomas of the extremities. Melphalan and tumor necrosis factor-alpha are used at a dosage that depends on the volume of the limb. Regional tissue volume is traditionally measured for the purposes of HILP using water displacement volumetry (WDV). Although this technique is considered the gold standard, it is time-consuming and complicated to implement, especially in obese and elderly patients. The aim of the present study was to compare the different methods described in the literature for calculating regional tissue volume in the HILP setting, and to validate an open source software. We reviewed the charts of 22 patients (11 males and 11 females) who had non-disseminated melanoma with in-transit metastases or sarcoma of the lower limb. We calculated the volume of the limb using four different methods: WDV, tape measurements and segmentation of computed tomography images using Osirix and Oncentra Masterplan softwares. The overall comparison provided a concordance correlation coefficient (CCC) of 0.92 for the calculations of whole limb volume. In particular, when Osirix was compared with Oncentra (validated for volume measures and used in radiotherapy), the concordance was near-perfect for the calculation of the whole limb volume (CCC = 0.99). With methods based on CT the user can choose a reliable plane for segmentation purposes. CT-based methods also provides the opportunity to separate the whole limb volume into defined tissue volumes (cortical bone, fat and water). Copyright © 2016 Elsevier Ltd. All rights reserved.

Anatomical variations between the sciatic nerve and the piriformis muscle: a contribution to surgical anatomy in piriformis syndrome.

PubMed

Natsis, Konstantinos; Totlis, Trifon; Konstantinidis, George A; Paraskevas, George; Piagkou, Maria; Koebke, Juergen

2014-04-01

To detect the variable relationship between sciatic nerve and piriformis muscle and make surgeons aware of certain anatomical features of each variation that may be useful for the surgical treatment of the piriformis syndrome. The gluteal region of 147 Caucasian cadavers (294 limbs) was dissected. The anatomical relationship between the sciatic nerve and the piriformis muscle was recorded and classified according to the Beaton and Anson classification. The literature was reviewed to summarize the incidence of each variation. The sciatic nerve and piriformis muscle relationship followed the typical anatomical pattern in 275 limbs (93.6 %). In 12 limbs (4.1 %) the common peroneal nerve passed through and the tibial nerve below a double piriformis. In one limb (0.3 %) the common peroneal nerve coursed superior and the tibial nerve below the piriformis. In one limb (0.3 %) both nerves penetrated the piriformis. In one limb (0.3 %) both nerves passed above the piriformis. Four limbs (1.4 %) presented non-classified anatomical variations. When a double piriformis muscle was present, two different arrangements of the two heads were observed. Anatomical variations of the sciatic nerve around the piriformis muscle were present in 6.4 % of the limbs examined. When dissection of the entire piriformis is necessary for adequate sciatic nerve decompression, the surgeon should explore for the possible existence of a second tendon, which may be found either inferior or deep to the first one. Some rare, unclassified variations of the sciatic nerve should be expected during surgical intervention of the region.

Dynamic parameters of three-point crutch gait in female patients after total hip arthroplasty.

PubMed

Murawa, Michał; Dworak, Lechosław B; Kabaciński, Jarosław; Syczewska, Małgorzata; Rzepnicka, Agata

2016-01-01

Patient recovery after a surgical procedure depends, among other factors, on the amount of the body weight with which patient loads lower limb. Research studies report different results of the degree of body weight with which lower limb is loaded during three-point crutch gait. The aim of this study was to evaluate the level of the ground reaction forces (GRF) during crutch gait used by patients after total hip arthroplasty (THA) in the first week after discharge from the orthopaedic units. Ten female patients diagnosed with primary unilateral coxarthrosis participated in a single measurement session. In order to record kinematic and dynamic variables of this gait pattern motion analysis system was used together with two force plates. The static test of body weight distribution between lower limbs was performed on a dual-top stabilometric plate. The average peak values of loading on the operated (O) limb during mid stance and terminal stance of three-point crutch gait were 64.6% and 64.3% of body weight (BW), respectively, whereas in the case of the nonoperated (NO) limb 103.5%BW and 108.8%BW, respectively. The maximum loads on the crutches were significantly higher (by 9%BW) on the NO side as compared to the O side ( p < 0.05). During the static test, average values of body weight distribution on the O and NO limb were 36%BW and 64%BW, respectively. The patients showed surprisingly similar level of loading on the O limb. The weight bearing on the O limb was lower during static trial than during three-point crutch gait.

Visual appearance of a virtual upper limb modulates the temperature of the real hand: a thermal imaging study in Immersive Virtual Reality.

PubMed

Tieri, Gaetano; Gioia, Annamaria; Scandola, Michele; Pavone, Enea F; Aglioti, Salvatore M

2017-05-01

To explore the link between Sense of Embodiment (SoE) over a virtual hand and physiological regulation of skin temperature, 24 healthy participants were immersed in virtual reality through a Head Mounted Display and had their real limb temperature recorded by means of a high-sensitivity infrared camera. Participants observed a virtual right upper limb (appearing either normally, or with the hand detached from the forearm) or limb-shaped non-corporeal control objects (continuous or discontinuous wooden blocks) from a first-person perspective. Subjective ratings of SoE were collected in each observation condition, as well as temperatures of the right and left hand, wrist and forearm. The observation of these complex, body and body-related virtual scenes resulted in increased real hand temperature when compared to a baseline condition in which a 3d virtual ball was presented. Crucially, observation of non-natural appearances of the virtual limb (discontinuous limb) and limb-shaped non-corporeal objects elicited high increase in real hand temperature and low SoE. In contrast, observation of the full virtual limb caused high SoE and low temperature changes in the real hand with respect to the other conditions. Interestingly, the temperature difference across the different conditions occurred according to a topographic rule that included both hands. Our study sheds new light on the role of an external hand's visual appearance and suggests a tight link between higher-order bodily self-representations and topographic regulation of skin temperature. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Quantifying frontal plane knee motion during single limb squats: reliability and validity of 2-dimensional measures.

PubMed

Gwynne, Craig R; Curran, Sarah A

2014-12-01

Clinical assessment of lower limb kinematics during dynamic tasks may identify individuals who demonstrate abnormal movement patterns that may lead to etiology of exacerbation of knee conditions such as patellofemoral joint (PFJt) pain. The purpose of this study was to determine the reliability, validity and associated measurement error of a clinically appropriate two-dimensional (2-D) procedure of quantifying frontal plane knee alignment during single limb squats. Nine female and nine male recreationally active subjects with no history of PFJt pain had frontal plane limb alignment assessed using three-dimensional (3-D) motion analysis and digital video cameras (2-D analysis) while performing single limb squats. The association between 2-D and 3-D measures was quantified using Pearson's product correlation coefficients. Intraclass correlation coefficients (ICCs) were determined for within- and between-session reliability of 2-D data and standard error of measurement (SEM) was used to establish measurement error. Frontal plane limb alignment assessed with 2-D analysis demonstrated good correlation compared with 3-D methods (r = 0.64 to 0.78, p < 0.001). Within-session (0.86) and between-session ICCs (0.74) demonstrated good reliability for 2-D measures and SEM scores ranged from 2° to 4°. 2-D measures have good consistency and may provide a valid measure of lower limb alignment when compared to existing 3-D methods. Assessment of lower limb kinematics using 2-D methods may be an accurate and clinically useful alternative to 3-D motion analysis when identifying individuals who demonstrate abnormal movement patterns associated with PFJt pain. 2b.

Where one hand meets the other: limb-specific and action-dependent movement plans decoded from preparatory signals in single human frontoparietal brain areas.

PubMed

Gallivan, Jason P; McLean, D Adam; Flanagan, J Randall; Culham, Jody C

2013-01-30

Planning object-directed hand actions requires successful integration of the movement goal with the acting limb. Exactly where and how this sensorimotor integration occurs in the brain has been studied extensively with neurophysiological recordings in nonhuman primates, yet to date, because of limitations of non-invasive methodologies, the ability to examine the same types of planning-related signals in humans has been challenging. Here we show, using a multivoxel pattern analysis of functional MRI (fMRI) data, that the preparatory activity patterns in several frontoparietal brain regions can be used to predict both the limb used and hand action performed in an upcoming movement. Participants performed an event-related delayed movement task whereby they planned and executed grasp or reach actions with either their left or right hand toward a single target object. We found that, although the majority of frontoparietal areas represented hand actions (grasping vs reaching) for the contralateral limb, several areas additionally coded hand actions for the ipsilateral limb. Notable among these were subregions within the posterior parietal cortex (PPC), dorsal premotor cortex (PMd), ventral premotor cortex, dorsolateral prefrontal cortex, presupplementary motor area, and motor cortex, a region more traditionally implicated in contralateral movement generation. Additional analyses suggest that hand actions are represented independently of the intended limb in PPC and PMd. In addition to providing a unique mapping of limb-specific and action-dependent intention-related signals across the human cortical motor system, these findings uncover a much stronger representation of the ipsilateral limb than expected from previous fMRI findings.

Planar covariance of upper and lower limb elevation angles during hand-foot crawling in healthy young adults.

PubMed

MacLellan, M J; Catavitello, G; Ivanenko, Y P; Lacquaniti, F

2017-11-01

Habitual quadrupeds have been shown to display a planar covariance of segment elevation angle waveforms in the fore and hind limbs during many forms of locomotion. The purpose of the current study was to determine if humans generate similar patterns in the upper and lower limbs during hand-foot crawling. Nine healthy young adults performed hand-foot crawling on a treadmill at speeds of 1, 2, and 3 km/h. A principal component analysis (PCA) was applied to the segment elevation angle waveforms for the upper (upper arm, lower arm, and hand) and lower (thigh, shank, and foot) limbs separately. The planarity of the elevation angle waveforms was determined using the sum of the variance explained by the first two PCs and the orientation of the covariance plane was quantified using the direction cosines of the eigenvector orthogonal to the plane, projected upon each of the segmental semi-axes. Results showed that planarity of segment elevation angles was maintained in the upper and lower limbs (explained variance >97%), although a slight decrease was present in the upper limb when crawling at 3 km/h. The orientation of the covariance plane was highly limb-specific, consistent with animal studies and possibly related to the functional neural control differences between the upper and lower limbs. These results may suggest that the motor patterns stored in the central nervous system for quadrupedal locomotion may be retained through evolution and may still be exploited when humans perform such tasks.

Limb-state information encoded by peripheral and central somatosensory neurons: Implications for an afferent interface

PubMed Central

Weber, Douglas J.; London, Brian M.; Hokanson, James A.; Ayers, Christopher A.; Gaunt, Robert A.; Torres, Ricardo R.; Zaaimi, Boubker; Miller, Lee E.

2013-01-01

A major issue to be addressed in the development of neural interfaces for prosthetic control is the need for somatosensory feedback. Here, we investigate two possible strategies: electrical stimulation of either dorsal root ganglia (DRG) or primary somatosensory cortex (S1). In each approach, we must determine a model that reflects the representation of limb state in terms of neural discharge. This model can then be used to design stimuli that artificially activate the nervous system to convey information about limb state to the subject. Electrically activating DRG neurons using naturalistic stimulus patterns, modeled on recordings made during passive limb movement, evoked activity in S1 that was similar to that of the original movement. We also found that S1 neural populations could accurately discriminate different patterns of DRG stimulation across a wide range of stimulus pulse-rates. In studying the neural coding of limb-state in S1, we also decoded the kinematics of active limb movement using multi-electrode recordings in the monkey. Neurons having both proprioceptive and cutaneous receptive fields contributed equally to this decoding. Some neurons were most informative of limb state in the recent past, but many others appeared to signal upcoming movements suggesting that they also were modulated by an efference copy signal. Finally, we show that a monkey was able to detect stimulation through a large percentage of electrodes implanted in area 2. We discuss the design of appropriate stimulus paradigms for conveying time-varying limb state information, and the relative merits and limitations of central and peripheral approaches. PMID:21878419

Body image and self-esteem in lower-limb amputees.

PubMed

Holzer, Lukas A; Sevelda, Florian; Fraberger, Georg; Bluder, Olivia; Kickinger, Wolfgang; Holzer, Gerold

2014-01-01

Limb amputation is often an inevitable procedure in the advanced condition of various diseases and poses a dramatic impact on a patient's life. The aim of the present study is to analyze the impact of lower-limb amputations on aesthetic factors such as body image and self-esteem as well as quality of life (QoL). 298 patients (149 uni- or bilateral lower-limb amputees and 149 controls) were included in this cross-sectional study in three centers. Demographic data was collected and patients received a 118-item questionnaire including the Multidimensional Body-Self Relations Questionnaire (MBSRQ), the Rosenberg Self-esteem (RSE) scale and the SF-36 Health Survey (QoL). ANOVA and student's t-test were used for statistical analysis. Unilateral lower-limb amputees showed a significant lower MBSRQ score of 3.07±0.54 compared with 3.41±0.34 in controls (p<0.001) and a lower score in the RSE compared to controls (21.63±4.72 vs. 21.46±5.86). However, differences were not statistically significant (p = 0.36). Patients with phantom pain sensation had a significantly reduced RSE (p = 0.01). The SF-36 health survey was significantly lower in patients with lower-limb amputation compared to controls (42.17±14.47 vs. 64.05±12.39) (p<0.001). This study showed that lower-limb amputations significantly influence patients' body image and QoL. Self-esteem seems to be an independent aspect, which is not affected by lower-limb amputation. However, self-esteem is influenced significantly by phantom pain sensation.

Measures of upper limb function for people with neck pain: a systematic review of measurement and practical properties (protocol).

PubMed

Alreni, Ahmad Salah Eldin; Harrop, Deborah; Gumber, Anil; McLean, Sionnadh

2015-04-07

Upper limb disability is a common musculoskeletal condition frequently associated with neck pain. Recent literature has reported the need to utilise validated upper limb outcome measures in the assessment and management of patients with neck pain. However, there is a lack of clear guidance about the suitability of available measures, which may impede utilisation. This review will identify all available measures of upper limb function developed for use in neck pain patients and evaluate their measurement and practical properties in order to identify those measures that are most appropriate for use in clinical practice and research. This review will be performed in two phases. Phase one will identify all measures used to assess upper limb function for patients with neck pain. Phase two will identify all available studies of the measurement and practical properties of identified instrument. The COnsensus-based Standards for selection of health Measurement INstrument (COSMIN) will be used to evaluate the methodological quality of the included studies. To ensure methodological rigour, the findings of this review will be reported in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guideline. Optimal management of patients with neck pain should incorporate upper limb rehabilitation. The findings of this study will assist clinicians who seek to utilise suitable and accurate measures to assess upper limb function for a patient with neck pain. In addition, the findings of this study may suggest new research directions to support the development of upper limb outcome measures for patients with neck pain. PROSPERO CRD42015016624.

Endovascular Recanalization of Chronically Occluded Native Arteries After Failed Bypass Surgery in Patients with Critical Ischemia.

PubMed

Yin, Minyi; Wang, Wei; Huang, Xintian; Hong, Biao; Liu, Xiaobing; Li, Weimin; Lu, Xinwu; Lu, Min; Jiang, Mier

2015-12-01

The study aimed to evaluate the feasibility, safety, and outcome of endovascular recanalization of native chronic total occlusions (CTO) in patients with critical limb ischemia (CLI) and lower extremities bypass graft failure. A retrospective review of CLI patients with failed lower limb grafts (>30 days after surgery) that underwent recanalization of native CTO was conducted in two institutions from January 2010 to June 2014. Twenty-eight patients (28 limbs) were included in the study, and all had limited surgical revascularization options. Demographics, procedural data, technical success, complications, vessel patency, limb salvage rates, and survival rates were analyzed. The mean follow-up period was 12.8 months. The technical success rate was 92.9% (26/28 limbs). The combined ipsilateral antegrade-retrograde approach was performed in nine limbs (32.1%). Major periprocedural (<30 days) complications included two myocardial infarctions (7.1%) and two stent thromboses (7.1%), resulting in one amputation. The ankle brachial index before discharge was significantly improved after recanalization (0.78 ± 0.08 vs. 0.31 ± 0.10, p < 0.01). The primary, assisted primary, and secondary patency rates at 12 months were 52.2, 65.8, and 82.2%, respectively. The limb salvage rate and amputation-free survival rate at 12 months were 91.6 and 87.0%, respectively. Endovascular recanalization of native CTO in patients with graft failure-related CLI is a feasible, safe, and effective procedure, with reasonable technical success, vessel patency, and limb salvage rates. The technique should be attempted before amputation in patients with limited surgical revascularization options.

Hip external rotation strength predicts hop performance after anterior cruciate ligament reconstruction.

PubMed

Kline, Paul W; Burnham, Jeremy; Yonz, Michael; Johnson, Darren; Ireland, Mary Lloyd; Noehren, Brian

2018-04-01

Quadriceps strength and single-leg hop performance are commonly evaluated prior to return to sport after anterior cruciate ligament reconstruction (ACLR). However, few studies have documented potential hip strength deficits after ACLR, or ascertained the relative contribution of quadriceps and hip strength to hop performance. Patients cleared for return to sports drills after ACLR were compared to a control group. Participants' peak isometric knee extension, hip abduction, hip extension, and hip external rotation (HER) strength were measured. Participants also performed single-leg hops, timed hops, triple hops, and crossover hops. Between-limb comparisons for the ACLR to control limb and the non-operative limb were made using independent two-sample and paired sample t tests. Pearson's correlations and stepwise multiple linear regression were used to determine the relationships and predictive ability of limb strength, graft type, sex, and limb dominance to hop performance. Sixty-five subjects, 20 ACLR [11F, age 22.8 (15-45) years, 8.3 ± 2 months post-op, mass 70.47 ± 12.95 kg, height 1.71 ± 0.08 m, Tegner 5.5 (3-9)] and 45 controls [22F, age 25.8 (15-45) years, mass 74.0 ± 15.2 kg, height 1.74 ± 0.1 m, Tegner 6 (3-7)], were tested. Knee extension (4.4 ± 1.5 vs 5.4 ± 1.8 N/kg, p = 0.02), HER (1.4 ± 0.4 vs 1.7 ± 0.5 N/kg, p = 0.04), single-leg hop (146 ± 37 vs 182 ± 38% limb length, p < 0.01), triple hop (417 ± 106 vs 519 ± 102% limb length, p < 0.01), timed hop (3.3 ± 2.0 vs 2.3 ± 0.6 s, p < 0.01), and crossover hop (364 ± 107 vs 446 ± 123% limb length, p = 0.01) were significantly impaired in the operative versus control subject limbs. Similar deficits existed between the operative and non-operative limbs. Knee extension and HER strength were significantly correlated with each of the hop tests, but only HER significantly predicted hop performance. After ACLR, patients have persistent HER strength, knee extension strength, and hop test deficits in the operative limb compared to the control and non-operative limbs, even after starting sport-specific drills. Importantly, HER strength independently predicted hop performance. Based on these findings, to resolve between-limb deficits in strength and hop performance clinicians should include HER strengthening exercises in post-operative rehabilitation. Prognostic Study, Level II.

A feasibility study of limb volume measuring systems

NASA Technical Reports Server (NTRS)

Lafferty, J. F.; Carter, W. M.

1974-01-01

Evaluation of the various techniques by which limb volume can be measured indicates that the odometric (electromechanical) method and the reflective scanner (optical) have a high probability of meeting the specifications of the LBNP experiments. Both of these methods provide segmental measurements from which the cross sectional area of the limb can be determined.

Behavioral and Neurophysiological Correlates of Striatal Dopamine Depletion: A Rodent Model of Parkinson's Disease

ERIC Educational Resources Information Center

Plowman, Emily K.; Kleim, Jeffrey A.

2011-01-01

Both limb and cranial motor functions are adversely impacted by Parkinson's disease (PD). While current pharmacological and surgical interventions are effective in alleviating general limb motor symptoms of PD, they have failed to provide significant benefit for cranial motor functions. This suggests that the neuropathologies mediating limb and…

Limbs beyond the Skin: Exploring the Physical Realities of Digital Composition

ERIC Educational Resources Information Center

Doerr-Stevens, Candance

2011-01-01

This article discusses how prolonged participation and digital composition online intersect to forge material extensions of the physical body, or limbs beyond the skin. Based on postmodern theories of technology and the body, I argue that these limbs, while less tangible, merit serious consideration given their potential to engender physical…

PTSD in Limb Trauma and Recovery

DTIC Science & Technology

2011-10-01

Virtual reality and Motion Analysis to Characterize Disabilities in Lower...Program 4: “ Virtual reality and Motion Analysis to Characterize Disabilities in Lower Limb Injury” (Christopher Rhea, Ph.D., lead investigator). This...ANSI Std. Z39.18 ANNUAL REPORT 10/16/2011 VIRTUAL REALITY AND MOTION ANALYSIS TO CHARACTERIZE DISABILITIES IN LOWER LIMB INJURY PI: SUSAN

Consumed Ischemia of Lower Limbs in the Newborn: A Case Report

PubMed Central

Hamid, Jiber; Rita, Hajji; Youssef, Zrihni; Abdellatif, Bouarhroum

2013-01-01

The limb ischemia is a rare phenomenon in the newborn. It is most often a postnatal ischemia secondary to arterial or venous catheterization, to neonatal infection. Maternal diabetes is most often implicated. The diagnosis implies an urgent situation which may result in extremity gangrene and ultimate loss of limb. PMID:24251263

Planar Covariation of Hindlimb and Forelimb Elevation Angles during Terrestrial and Aquatic Locomotion of Dogs

PubMed Central

Catavitello, Giovanna; Ivanenko, Yuri P.; Lacquaniti, Francesco

2015-01-01

The rich repertoire of locomotor behaviors in quadrupedal animals requires flexible inter-limb and inter-segmental coordination. Here we studied the kinematic coordination of different gaits (walk, trot, gallop, and swim) of six dogs (Canis lupus familiaris) and, in particular, the planar covariation of limb segment elevation angles. The results showed significant variations in the relative duration of rearward limb movement, amplitude of angular motion, and inter-limb coordination, with gait patterns ranging from a lateral sequence of footfalls during walking to a diagonal sequence in swimming. Despite these differences, the planar law of inter-segmental coordination was maintained across different gaits in both forelimbs and hindlimbs. Notably, phase relationships and orientation of the covariation plane were highly limb specific, consistent with the functional differences in their neural control. Factor analysis of published muscle activity data also demonstrated differences in the characteristic timing of basic activation patterns of the forelimbs and hindlimbs. Overall, the results demonstrate that the planar covariation of inter-segmental coordination has emerged for both fore- and hindlimbs and all gaits, although in a limb-specific manner. PMID:26218076

Blastema induction in aneurogenic state and Prrx-1 regulation by MMPs and FGFs in Ambystoma mexicanum limb regeneration.

PubMed

Satoh, Akira; makanae, Aki; Hirata, Ayako; Satou, Yutaka

2011-07-15

Urodele amphibians can regenerate amputated limbs. It has been considered that differentiated dermal tissues generate multipotent and undifferentiated cells called blastema cells during limb regeneration. In early phases of limb regeneration, blastema cells are induced by nerves and the apical epithelial cap (AEC). We had previously investigated the role of neurotrophic factors in blastema or blastema-like formation consisting of Prrx-1 positive cells. A new system suitable for investigating early phases of limb regeneration, called the accessory limb model (ALM), was recently developed. In this study, we performed a comparative transcriptome analysis between a blastema and wound using ALM. Matrix metalloproteinase (MMP) and fibroblast growth factor (FGF) signaling components were observed to be predominantly expressed in ALM blastema cells. Furthermore, we found that MMP activity induced a blastema marker gene, Prrx-1, in vitro, and FGF signaling pathways worked in coordination to maintain Prrx-1 expression and ALM blastema formation. Furthermore, we demonstrated that these two activities were sufficient to induce an ALM blastema in the absence of a nerve in vivo. Copyright © 2011 Elsevier Inc. All rights reserved.

Clinical practice guidelines for the management of acute limb compartment syndrome following trauma.

PubMed

Wall, Christopher J; Lynch, Joan; Harris, Ian A; Richardson, Martin D; Brand, Caroline; Lowe, Adrian J; Sugrue, Michael

2010-03-01

Acute compartment syndrome is a serious and not uncommon complication of limb trauma. The condition is a surgical emergency, and is associated with significant morbidity if not managed appropriately. There is variation in management of acute limb compartment syndrome in Australia. Clinical practice guidelines for the management of acute limb compartment syndrome following trauma were developed in accordance with Australian National Health and Medical Research Council recommendations. The guidelines were based on critically appraised literature evidence and the consensus opinion of a multidisciplinary team involved in trauma management who met in a nominal panel process. Recommendations were developed for key decision nodes in the patient care pathway, including methods of diagnosis in alert and unconscious patients, appropriate assessment of compartment pressure, timing and technique of fasciotomy, fasciotomy wound management, and prevention of compartment syndrome in patients with limb injuries. The recommendations were largely consensus based in the absence of well-designed clinical trial evidence. Clinical practice guidelines for the management of acute limb compartment syndrome following trauma have been developed that will support consistency in management and optimize patient health outcomes.

Klippel-Trenaunay syndrome in a Border collie.

PubMed

de Cock, H; Mols, N; van Roy, M R; Ducatelle, R; Simoens, P

1996-10-01

A Border collie was presented at the age of 9 weeks with several lesions of the right forelimb, including a reddish-blue haemangiomatous macula in the medio-dorsal part of the elbow, multiple, scattered small cavernous haemangioma-like lesions at the plantar part of the foot and a general hypertrophy of the limb. X-rays of the limb showed osteolysis. On skin biopsy, telangiectatic veins were observed. The rest of the body did not show any skin lesions or hypertrophy. The dog was otherwise healthy. Due to the extension of the lesions and worsening of the limb swelling, it was decided to amputate the affected limb. The dog remained healthy for 2 weeks, but then passed through episodes of anaemia, and finally died suddenly with signs of shock. Dissection of the limb after amputation revealed hypoplasia and aplasia of the deep venous system in the lower part of the leg. No arterio-venous shunts were noticed. ln man, this syndrome, characterised by an insufficiently developed deep venous system associated with local overgrowth of the limb and cutaneous telangiectasia, is known as Klippel-Trenaunay syndrome.

Synchronous multifocal necrotizing fasciitis prognostic factors: a retrospective case series study in a single center.

PubMed

Lee, Ching-Yu; Li, Yen-Yao; Huang, Tsan-Wen; Huang, Tsung-Yu; Hsu, Wei-Hsiu; Tsai, Yao-Hung; Huang, Jou-Chen; Huang, Kuo-Chin

2016-12-01

No reports have been published on synchronous multifocal necrotizing fasciitis (SMNF), a multifocal presence of necrotizing fasciitis in different extremities. We evaluated the clinical characteristics and outcomes of SMNF. Eighteen patients (14 men, 4 women; mean age: 59 years) diagnosed with SMNF of the extremities between January 2004 to December 2012 were enrolled and evaluated. Vibrio species were the most commonly (78%; n = 14) isolated; others were two cases (11%) of Aeromonas spp., one case (6%) of group A β-hemolytic streptococcus, and one case of coagulase-negative staphylococcus. SMNF was in the bilateral lower limbs (72%; n = 13), bilateral upper limbs (17%; n = 3), and one patient with one upper and one lower limb (11%). Non-surviving patients had more bilateral lower limb involvement and thrombocytopenia. Most patients with SMNF were male and had bilateral lower limb and marine Gram-negative bacteria involvement. The mortality of SMNF remained extremely high in patients with involvement of bilateral lower limb and initial thrombocytopenia.

The role of early development in mammalian limb diversification: a descriptive comparison of early limb development between the Natal long-fingered bat (Miniopterus natalensis) and the mouse (Mus musculus).

PubMed

Hockman, Dorit; Mason, Mandy K; Jacobs, David S; Illing, Nicola

2009-04-01

Comparative embryology expands our understanding of unique limb structures, such as that found in bats. Bat forelimb digits 2 to 5 are differentially elongated and joined by webbing, while the hindlimb digits are of similar length in many species. We compare limb development between the mouse and the Natal long-fingered bat, Miniopterus natalensis, to pinpoint the stage at which their limbs begin to differ. The bat forelimb differs from the mouse at Carollia stage (CS) 14 with the appearance of the wing membrane primordia. This difference is enhanced at CS 15 with the posterior expansion of the hand plate. The bat hindlimb begins to differ from the mouse between CS 15 and 16 when the foot plate undergoes a proximal expansion resulting in digit primordia of very similar length. Our findings support recent gene expression studies, which reveal a role for early patterning in the development of the bat limb. Copyright 2009 Wiley-Liss, Inc.

Impact of revascularization and factors associated with limb salvage in patients with diabetic foot.

PubMed

Hinojosa, Carlos A; Boyer-Duck, Estefanía; Anaya-Ayala, Javier E; Núñez-Salgado, Ana E; Laparra-Escareno, Hugo; Lizola, René

2018-01-01

Diabetic foot is a common cause of hospitalization. To examine the impact of revascularization on lower limb salvage. Retrospective study of diabetic patients with foot ulcers. The extent of tissue loss was assessed according to the PEDIS and Wagner classifications, and revascularization indications and techniques were evaluated. Factors involved with major amputation and limb salvage were assessed with Fisher's and chi-square tests. A total of 307 patients with a mean age of 61 years were included in the study; 198 (64%) were males; 53 (17%) underwent limb revascularization, 26 (8%) with endovascular techniques and 27 (9%) with open surgery; 27 belonged to PEDIS grade 3 (51%) and 21 (41%) to Wagner's classification grade 4; 52% of revascularized patients required major amputation versus 25% of those without revascularization. Comorbidities, demographic variables, complications and mortality showed no differences when patients who required major amputation were compared with those who didn't. Despite revascularization, the limb was preserved in less than 50% of patients. Early referral to vascular surgery and appropriate patient-selection criteria might increase limb salvage. Copyright: © 2018 SecretarÍa de Salud.

Comparison of laterality index of upper and lower limb movement using brain activated fMRI

NASA Astrophysics Data System (ADS)

Harirchian, Mohammad Hossein; Oghabian, Mohammad Ali; Rezvanizadeh, Alireza; Bolandzadeh, Niousha

2008-03-01

Asymmetry of bilateral cerebral function, i.e. laterality, is an important phenomenon in many brain actions such as motor functions. This asymmetry maybe altered in some clinical conditions such as Multiple Sclerosis (MS). The aim of this study was to delineate the laterality differences for upper and lower limbs in healthy subjects to compare this pattern with subjects suffering from MS in advance. Hence 9 Male healthy subjects underwent fMRI assessment, while they were asked to move their limbs in a predetermined pattern. The results showed that hands movement activates the brain with a significant lateralization in pre-motor cortex in comparison with lower limb. Also, dominant hands activate brain more lateralized than the non-dominant hand. In addition, Left basal ganglia were observed to be activated regardless of the hand used, While, These patterns of Brain activation was not detected in lower limbs. We hypothesize that this difference might be attributed to this point that hand is usually responsible for precise and fine voluntary movements, whereas lower limb joints are mainly responsible for locomotion, a function integrating voluntary and automatic bilateral movements.

A STUDY OF SOLAR PHOTOSPHERIC TEMPERATURE GRADIENT VARIATION USING LIMB DARKENING MEASUREMENTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Criscuoli, Serena; Foukal, Peter

2017-01-20

The variation in area of quiet magnetic network measured over the sunspot cycle should modulate the spatially averaged photospheric temperature gradient, since temperature declines with optical depth more gradually in magnetic flux tube atmospheres. Yet, limb darkening measurements show no dependence upon activity level, even at an rms precision of 0.04%. We study the sensitivity of limb darkening to changes in area filling factor using a 3D MHD model of the magnetized photosphere. The limb darkening change expected from the measured 11-year area variation lies below the level of measured limb darkening variations, for a reasonable range of magnetic fluxmore » in quiet network and internetwork regions. So the remarkably constant limb darkening observed over the solar activity cycle is not inconsistent with the measured 11-year change in area of quiet magnetic network. Our findings offer an independent constraint on photospheric temperature gradient changes reported from measurements of the solar spectral irradiance from the Spectral Irradiance Monitor, and recently, from wavelength-differential spectrophotometry using the Solar Optical Telescope aboard the HINODE spacecraft.« less

Design and preliminary evaluation of an exoskeleton for upper limb resistance training

NASA Astrophysics Data System (ADS)

Wu, Tzong-Ming; Chen, Dar-Zen

2012-06-01

Resistance training is a popular form of exercise recommended by national health organizations, such as the American College of Sports Medicine (ACSM) and the American Heart Association (AHA). This form of training is available for most populations. A compact design of upper limb exoskeleton mechanism for homebased resistance training using a spring-loaded upper limb exoskeleton with a three degree-of-freedom shoulder joint and a one degree-of-freedom elbow joint allows a patient or a healthy individual to move the upper limb with multiple joints in different planes. It can continuously increase the resistance by adjusting the spring length to train additional muscle groups and reduce the number of potential injuries to upper limb joints caused by the mass moment of inertia of the training equipment. The aim of this research is to perform a preliminary evaluation of the designed function by adopting an appropriate motion analysis system and experimental design to verify our prototype of the exoskeleton and determine the optimal configuration of the spring-loaded upper limb exoskeleton.

High-Pressure Transvenous Perfusion of the Upper Extremity in Human Muscular Dystrophy: A Safety Study with 0.9% Saline.

PubMed

Fan, Zheng; Kocis, Keith; Valley, Robert; Howard, James F; Chopra, Manisha; Chen, Yasheng; An, Hongyu; Lin, Weili; Muenzer, Joseph; Powers, William

2015-09-01

We evaluated safety and feasibility of high-pressure transvenous limb perfusion in an upper extremity of adult patients with muscular dystrophy, after completing a similar study in a lower extremity. A dose escalation study of single-limb perfusion with 0.9% saline was carried out in nine adults with muscular dystrophies under intravenous analgesia. Our study demonstrates that it is feasible and definitely safe to perform high-pressure transvenous perfusion with 0.9% saline up to 35% of limb volume in the upper extremities of young adults with muscular dystrophy. Perfusion at 40% limb volume is associated with short-lived physiological changes in peripheral nerves without clinical correlates in one subject. This study provides the basis for a phase 1/2 clinical trial using pressurized transvenous delivery into upper limbs of nonambulatory patients with Duchenne muscular dystrophy. Furthermore, our results are applicable to other conditions such as limb girdle muscular dystrophy as a method for delivering regional macromolecular therapeutics in high dose to skeletal muscles of the upper extremity.

Skeletal muscle responses to lower limb suspension in humans

NASA Technical Reports Server (NTRS)

Hather, Bruce M.; Adams, Gregory R.; Tesch, Per A.; Dudley, Gary A.

1992-01-01

The morphological responses of human skeletal muscle to unweighting were assessed by analyzing multiple transaxial magnetic resonance (MR) images of both lower limbs and skeletal muscle biopsies of the unweighted lower limb before and after six weeks of unilaterial (left) lower limb suspension (ULLS). Results indicated that, as a results of 6 weeks of unweighting (by the subjects walking on crutches using only one limb), the cross sectional area (CSA) of the thigh muscle of the unweighted left limb decreased 12 percent, while the CSA of the right thigh muscle did not change. The decrease was due to a twofold greater response of the knee extensors than the knee flexors. The pre- and post-ULLS biopsies of the left vastus lateralis showed a 14 percent decrease in average fiber CSA due to unweighting. The number of capillaries surrounding the different fiber types was unchanged after ULLS. Results showed that the adaptive responses of human skeletal muscle to unweighting are qualitatively, but not quantitatively, similar to those of lower mammals and not necessarily dependent on the fiber-type composition.

Gastrointestinal symptoms, motility, and transit after the Roux-en-Y operation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Perino, L.E.; Adcock, K.A.; Goff, J.S.

1988-04-01

Roux-en-Y patients have symptoms that vary from almost none to inability to tolerate oral feedings. This study was designed to determine whether there is a relationship between a patient's symptoms and the function of the gastric remnant or the Roux-limb. Gastric remnant and Roux-limb emptying were studied in eight patients with technetium-99m-labeled oatmeal and Roux-limb motor activity was measured with a water-perfused manometry system. We found that gastric emptying was rarely significantly slowed, but emptying of the Roux-limb was delayed in several patients. We also found that there was a rough correlation between the patient's symptoms and the degree ofmore » abnormal motility found in the Roux-limb. There is no known reason for these abnormalities in Roux-limb function in some patients after a Roux-en-Y, but our finding of worse abnormalities in those who had multiple previous gastric surgeries suggests that the symptoms and dysfunction may be related to the number of surgeries, as well as to the type of surgery.« less

Using upper limb kinematics to assess cognitive deficits in people living with both HIV and stroke.

PubMed

Bui, Kevin D; Rai, Roshan; Johnson, Michelle J

2017-07-01

In this study, we aim to explore ways to objectively assess cognitive deficits in the stroke and HIV/stroke populations, where cognitive and motor impairments can be hard to separate. Using an upper limb rehabilitation robot called the Haptic TheraDrive, we collect performance error scores and motor learning data on the impaired and unimpaired limb during a trajectory tracking task. We compare these data to clinical cognitive scores. The preliminary results suggest a possible relationship between unimpaired upper limb performance error and visuospatial/executive function cognitive domains, but more work needs to be done to further investigate this. The potential of using robot-assisted technologies to measure unimpaired limb kinematics as a tool to assess cognitive deficits would be useful to inform more effective rehabilitation strategies for HIV, stroke, and HIV/stroke populations.

Relationship between agility and lower limb muscle strength, targeting university badminton players.

PubMed

Sonoda, Takuya; Tashiro, Yuto; Suzuki, Yusuke; Kajiwara, Yu; Zeidan, Hala; Yokota, Yuki; Kawagoe, Mirei; Nakayama, Yasuaki; Bito, Tsubasa; Shimoura, Kanako; Tatsumi, Masataka; Nakai, Kengo; Nishida, Yuichi; Yoshimi, Soyoka; Aoyama, Tomoki

2018-02-01

[Purpose] Targeting university badminton players, this study investigated the relationship between agility, which is associated with performance in badminton, and lower limb muscle strength, and examined which muscles influence agility. [Subjects and Methods] A total of 23 male university badminton players were evaluated for side-shuffle test scores and lower limb strength. The relationships between agility, lower limb strength, and duration of experience playing badminton were evaluated using a correlation analysis. Moreover, the relationship between agility and lower limb strength was evaluated by partial correlation analysis, adjusting for the effects of experience of each badminton player. [Results] The agility score correlated with hip extension and ankle plantar flexion strength, with adjustment for badminton experience. [Conclusion] This study suggests that hip extension training and improvement in ankle plantar flexion strength may improve agility.

Recording electrocardiograms using 3-limb lead cables instead of the standard 4: a modification to minimize incorrect electrode placements.

PubMed

Soliman, Elsayed Z

2008-01-01

The similarity between and the number of limb lead cables play an important role in the frequency of incorrect connection of limb electrodes. Hence, a modified electrocardiogram (ECG) acquisition procedure is proposed in this brief communication, whereby the left-leg (LL) and right-leg (RL) electrode cables are combined into 1 cable, referred to as combined LL/RL cable. The electrode wires in the combined LL/RL cable are connected to 2 electrodes placed on both sides of the LL. The combined LL/RL cable is unique enough (being thicker) not to be mistaken with the upper limb electrode cables. The proposed modification will not in any way influence the ECG waveforms or amplitudes, and it can be expected to substantially reduce incorrect limb electrode placements.

Application of autologous platelet-rich plasma to enhance wound healing after lower limb revascularization: A case series and literature review.

PubMed

Massara, Mafalda; Barillà, David; De Caridi, Giovanni; Serra, Raffaele; Volpe, Alberto; Surace, Rosangela; Foti, Giovanni; Marcuccio, Daniela; Pucci, Giulia; Volpe, Pietro

2015-01-01

Dermal tissue loss in patients affected by critical limb ischemia represents a serious wound-healing problem, with high morbidity, prolonged hospital stay, and high patient care costs. Treatment of ischemic foot lesions requires limb revascularization by endovascular or open surgical intervention and individualized patient-specific wound care, including antibiotic therapy; devitalized/infected wound debridement; and advanced wound dressing. In selected patients, spinal cord stimulation, vacuum-assisted closure therapy, and bioengineered tissue or skin substitutes and growth factors have been shown to improve wound healing. In this study, we present our preliminary results on topical application of autologous platelet-rich plasma to enhance the process of wound healing after revascularization of lower limbs in patients affected by critical limb ischemia. Copyright © 2016 Elsevier Inc. All rights reserved.

Risk factors of the upper limb disorders among cashiers in grocery retail industries: A review

NASA Astrophysics Data System (ADS)

Zuhaidi, Muhammad Fareez Ahmad; Nasrull Abdol Rahman, Mohd

2017-08-01

Cashiers have been appointed as one of top ten occupations in developing musculoskeletal disorders (MSDs) particularly on the upper limb. Many of the workers are still in high risk injury due to incorrect workstations and lack of employee education in basic biomechanical principles. Normally, cashiers are exposed in several risk factors such as awkward and static postures, repetition motion and forceful exertions. Thus, cashiers in supermarket are considered at risk from developing upper limb disorders (ULDs). This review evaluates selected papers that have studied risk factors of the upper limb disorders among cashiers in grocery retail industries. In addition, other studies from related industry were reviewed as applicable. In order to understand risk factors of the upper limb disorders among cashiers, it is recommended that future studies are needed in evaluating these risk factors among cashiers.

Limb reduction defects in the northern region of England 1985-92.

PubMed Central

Wright, M J; Newell, J N; Charlton, M E; Hey, E N; Donaldson, L J; Burn, J

1995-01-01

STUDY OBJECTIVE--To test the hypothesis that children born to mothers living near the sea are at increased risk of limb reduction defects. DESIGN--Descriptive data analysis. SETTING--The northern health region of England. PATIENTS--All children born between 1 January 1985 and 31 December 1992 in the northern region of England with isolated limb reduction defects. MAIN RESULTS--The birth prevalence of isolated limb reduction defects was not affected by the distance the mother lived from the sea. There was some evidence of space-time clustering, but there was no evidence of statistically significant variation in the occurrence of the condition with sex, time of birth (monthly or yearly), or county of birth. CONCLUSIONS--There is no evidence that children born to mothers living near the sea are at increased risk of limb reduction defects. PMID:7629469

The benefit of limb cloud imaging for tropospheric infrared limb sounding

NASA Astrophysics Data System (ADS)

Adams, S.; Spang, R.; Preusse, P.; Heinemann, G.

2009-03-01

Advances in detector technology enable a new generation of infrared limb sounders to measure 2-D images of the atmosphere. A proposed limb cloud imager (LCI) mode will measure clouds with very high spatial resolution. For the inference of temperature and trace gas distributions, detector pixels of the LCI have to be combined into super-pixels which provide the required signal-to-noise ratio and information content for the retrievals. This study examines the extent to which tropospheric coverage can be improved in comparison to limb sounding using a fixed field of view with the size of the super-pixels, as in conventional limb sounders. The study is based on cloud topographies derived from (a) IR brightness temperatures (BT) of geostationary weather satellites in conjunction with ECMWF temperature profiles and (b) ice and liquid water content data of the Consortium for Small-scale Modeling-Europe (COSMO-EU) of the German Weather Service. Limb cloud images are simulated by matching the cloud topography with the limb sounding line of sight (LOS). The analysis of the BT data shows that the reduction of the spatial sampling along the track has hardly any effect on the gain in information. The comparison between BT and COSMO-EU data identifies the strength of both data sets, which are the representation of the horizontal cloud extent for the BT data and the reproduction of the cloud amount for the COSMO-EU data. The results of the analysis of both data sets show the great advantage of the cloud imager. However, because both cloud data sets do not present the complete fine structure of the real cloud fields in the atmosphere it is assumed that the results tend to underestimate the increase in information. In conclusion, real measurements by such an instrument may result in an even higher benefit for tropospheric limb retrievals.

Pharmacokinetics, pharmacodynamics and local tolerance at injection site of marbofloxacin administered by regional intravenous limb perfusion in standing horses.

PubMed

Lallemand, Elodie; Trencart, Pierre; Tahier, Carine; Dron, Frederic; Paulin, Angelique; Tessier, Caroline

2013-08-01

To evaluate pharmacokinetic-pharmacodynamic variables and local tolerance at injection-site of marbofloxacin administered via regional intravenous limb perfusion (RIVLP) in standing horses. Adult horses (n = 6). RIVLP were performed with rubber tourniquets applied to the forelimbs of standing sedated horses. Marbofloxacin (0.67 mg/kg) was randomly injected in 1 forelimb, with the contralateral limb serving as a control (0.9% NaCl solution). Samples of jugular blood and synovial fluid from the radiocarpal joint of the marbofloxacin-perfused limb were collected before and at intervals after RIVLP for determination of drug concentrations. All injection sites were evaluated before, 24 and 48 hours after RIVLP by means of ultrasonographic examination, circumferential measurements and subjective visible inflammation scores by veterinarians unaware of treatment received. No adverse effects associated with the technique or antibiotic were observed. High marbofloxacin concentrations were obtained in the synovial fluid, AUCINF was significantly higher in synovial fluid than in plasma (78.64 ± 49.41 and 2.85 ± 0.60 µg h/mL respectively, P = .028). The efficacy indices, AUC0-24 /MIC90 and Cmaxobs/MIC90 , predicted a favorable outcome in the treatment of synovial fluid infections caused by enterobacteriaceae and Staphylococcus aureus. After RIVLP, there was no statistically significant difference between marbofloxacin-injected and control limbs for lameness, visual inflammation score, limb circumference, and ultrasonographic appearance of the veins. Marbofloxacin injected limbs had a significantly greater subcutaneous thickness, compared with control limbs. These data suggest that RIVLP of marbofloxacin (0.67 mg/kg) could be a safe and effective method for treatment of infections of the distal portion of the limb for susceptible organisms. © Copyright 2013 by The American College of Veterinary Surgeons.

Network based transcription factor analysis of regenerating axolotl limbs

PubMed Central

2011-01-01

Background Studies on amphibian limb regeneration began in the early 1700's but we still do not completely understand the cellular and molecular events of this unique process. Understanding a complex biological process such as limb regeneration is more complicated than the knowledge of the individual genes or proteins involved. Here we followed a systems biology approach in an effort to construct the networks and pathways of protein interactions involved in formation of the accumulation blastema in regenerating axolotl limbs. Results We used the human orthologs of proteins previously identified by our research team as bait to identify the transcription factor (TF) pathways and networks that regulate blastema formation in amputated axolotl limbs. The five most connected factors, c-Myc, SP1, HNF4A, ESR1 and p53 regulate ~50% of the proteins in our data. Among these, c-Myc and SP1 regulate 36.2% of the proteins. c-Myc was the most highly connected TF (71 targets). Network analysis showed that TGF-β1 and fibronectin (FN) lead to the activation of these TFs. We found that other TFs known to be involved in epigenetic reprogramming, such as Klf4, Oct4, and Lin28 are also connected to c-Myc and SP1. Conclusions Our study provides a systems biology approach to how different molecular entities inter-connect with each other during the formation of an accumulation blastema in regenerating axolotl limbs. This approach provides an in silico methodology to identify proteins that are not detected by experimental methods such as proteomics but are potentially important to blastema formation. We found that the TFs, c-Myc and SP1 and their target genes could potentially play a central role in limb regeneration. Systems biology has the potential to map out numerous other pathways that are crucial to blastema formation in regeneration-competent limbs, to compare these to the pathways that characterize regeneration-deficient limbs and finally, to identify stem cell markers in regeneration. PMID:21418574

Lower limb injuries in men's elite Gaelic football: A prospective investigation among division one teams from 2008 to 2015.

PubMed

Roe, Mark; Murphy, John C; Gissane, Conor; Blake, Catherine

2018-02-01

To prospectively investigate incidence and associated time-loss of lower limb injuries in elite Gaelic football. Additionally, to identify sub-groups of elite players at increased risk of sustaining a lower limb injury. Prospective, epidemiological study. Team physiotherapists provided exposure and injury on a weekly basis to the National Gaelic Athletic Association (GAA) Injury Surveillance Database. Injury was defined using a time-loss criterion. Fifteen different teams participated throughout the 8-year study providing 36 team datasets from 2008 to 2015. Lower limb injuries (n=1239) accounted for 83.5% (95% CI 82.0-85.0) and 77.6% (95% CI 75.8-79.4) of training and match-play injuries, respectively. Injury incidence was 4.5 (95% CI 3.7-5.2) and 38.4 (95% CI 34.3-42.60) per 1000 training and match-play hours, respectively. One-in-four (25.0%, 95% CI 22.4-27.0) lower limb injuries were recurrent. Non-contact injuries accounted for 80.9% (95% CI 79.2-82.6) of cases. The median team rate was 30 (IQR 24-43) lower limb injuries per season resulting in 840.8 (95% CI 773.3-908.2) time-loss days. Previously injured players had a 2.5-times (OR 95% CI 2.2-2.8) greater risk of sustaining a lower limb injury. Overall, 56.8% of players with a previous lower limb injury sustained another. Incidence was higher for forward players and those aged >25years. Lower limb injuries are the most common injury among elite division one Gaelic football teams. Injury risk management should become an ongoing component of a player's development programme and consider injury history, age, and playing position. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Impact of the bacteriology of diabetic foot ulcers in limb loss.

PubMed

Hinojosa, Carlos A; Boyer-Duck, Estefania; Anaya-Ayala, Javier E; Nunez-Salgado, Ana; Laparra-Escareno, Hugo; Torres-Machorro, Adriana; Lizola, Rene

2016-09-01

Infections in feet of patients with diabetes mellitus is common, complex and costly. The aim of this study to investigate the isolated microorganisms in infected diabetic foot ulcers, and the impact of these infectious agents in limb loss in a tertiary medical center in Mexico City. We conducted a retrospective review in diabetic patients with infected foot ulcers from 1997 to 2014. Diabetic foot was defined according to the World Health Organization (WHO), the bacteriology of wound cultures and the impact of microorganisms in limb loss (major amputation) was studied. Patient's demographics, comorbidities, wound characteristics, and other factors associated in clinical outcomes were determined. A total of 165 subjects with soft tissue infections and/or osteomyelitis and positive cultures were included. One hundred and five (64%) were male, with a mean age of 60 year old +/- 15. One hundred fifty-nine (96%) had Type 2 diabetes mellitus, 68 (41%) history of peripheral arterial disease (PAD) and 97 (59%) patients had osteomyelitis. In 89 patients (54%), cultures were polymicrobial and one single organism was isolated in 76 cultures (46%). During the follow up, 96 (58%) patients preserved their limbs and 69 (42%) required major amputation (above or below knee). Sixty percent of patients that suffered from limb loss had polymicrobial culture (p = 0.13). Growth of Escherichia coli and Enterococcus faecium (p = 0.03) and E. coli and Morganella morgagnii (p = 0.03) was associated to limb loss. Among monomicrobial cultures, infections associated with Proteous mirabilis had higher rate of progression to limb loss (p = 0.03). PAD was associated to limb loss (p = 0.001). Management of diabetic foot requires a multimodality approach. In this study, in patients that received appropriate antibiotic therapy and optimal surgical management, we observed that history of PAD, polymicrobial and isolated P. mirabilis infections were variables associated with higher rate of limb loss. © 2016 by the Wound Healing Society.

Review: Biological and Molecular Differences between Tail Regeneration and Limb Scarring in Lizard: An Inspiring Model Addressing Limb Regeneration in Amniotes.

PubMed

Alibardi, Lorenzo

2017-09-01

Tissue regeneration in lizards represents a unique model of regeneration and scarring in amniotes. The tail and limb contain putative stem cells but also dedifferentiating cells contribute to regeneration. Following tail amputation, inflammation is low and cell proliferation high, leading to regeneration while the intense inflammation in the limb leads to low proliferation and scarring. FGFs stimulate tail and limb regeneration and are present in the wound epidermis and blastema while they disappear in the limb wound epidermis 2-3 weeks postamputation in the scarring outgrowth. FGFs localize in the tail blastema and the apical epidermal peg (AEP), an epidermal microregion that allows tail growth but is absent in the limb. Inflammatory cells invade the limb blastema and wound epidermis, impeding the formation of an AEP. An embryonic program of growth is activated in the tail, dominated by Wnt-positive and -negative regulators of cell proliferation and noncoding RNAs, that represent the key regenerative genes. The balanced actions of these regulators likely impede the formation of a tumor in the tail tip. Genes for FACIT and fibrillar collagens, protease inhibitors, and embryonic keratins are upregulated in the regenerating tail blastema. A strong downregulation of genes for both B and T-lymphocyte activation suggests the regenerating tail blastema is a temporal immune-tolerated organ, whereas a scarring program is activated in the limb. Wnt inhibitors, pro-inflammatory genes, negative regulators of cell proliferation, downregulation of myogenic genes, proteases, and oxidases favoring scarring are upregulated. The evolution of an efficient immune system may be the main limiting barrier for organ regeneration in amniotes, and the poor regeneration of mammals and birds is associated with the efficiency of their mature immune system. This does not tolerate embryonic antigens formed in reprogrammed embryonic cells (as for neoplastic cells) that are consequently eliminated impeding the regeneration of lost organs. © 2017 Wiley Periodicals, Inc.

Resveratrol Increases Nitric Oxide Production in the Rat Thick Ascending Limb via Ca2+/Calmodulin

PubMed Central

Gonzalez-Vicente, Agustin; Cabral, Pablo D.; Garvin, Jeffrey L.

2014-01-01

The thick ascending limb of the loop of Henle reabsorbs 30% of the NaCl filtered through the glomerulus. Nitric oxide (NO) produced by NO synthase 3 (NOS3) inhibits NaCl absorption by this segment. Resveratrol, a polyphenol, has beneficial cardiovascular and renal effects, many of which are mediated by NO. Resveratrol increases intracellular Ca2+ (Cai) and AMP kinase (AMPK) and NAD-dependent deacetylase sirtuin1 (SIRT1) activities, all of which could activate NO production. We hypothesized that resveratrol stimulates NO production by thick ascending limbs via a Ca2+/calmodulin-dependent mechanism. To test this, the effect of resveratrol on NO bioavailability was measured in thick ascending limb suspensions. Cai was measured in single perfused thick ascending limbs. SIRT1 activity and expression were measured in thick ascending limb lysates. Resveratrol (100 µM) increased NO bioavailability in thick ascending limb suspensions by 1.3±0.2 AFU/mg/min (p<0.03). The NOS inhibitor L-NAME blunted resveratrol-stimulated NO bioavailability by 96±11% (p<0.03). The superoxide scavenger tempol had no effect. Resveratrol elevated Cai from 48±7 to 135±24 nM (p<0.01) in single tubules. In Ca2+-free media, the resveratrol-induced increase in NO was blunted by 60±20% (p<0.05) and the rise in Cai reduced by 80%. Calmodulin inhibition prevented the resveratrol-induced increase in NO (p<0.002). AMPK inhibition had no effect. Resveratrol did not increase SIRT1 activity. We conclude that resveratrol increases NO production in thick ascending limbs via a Ca2+/calmodulin dependent mechanism, and SIRT1 and AMPK do not participate. Resveratrol-stimulated NO production in thick ascending limbs may account for part of its beneficial effects. PMID:25314136

Ipsilateral and contralateral foot pronation affect lower limb and trunk biomechanics of individuals with knee osteoarthritis during gait.

PubMed

Resende, Renan A; Kirkwood, Renata N; Deluzio, Kevin J; Hassan, Elizabeth A; Fonseca, Sérgio T

2016-05-01

Lateral wedges have been suggested for the treatment of individuals with knee osteoarthritis, but it may have undesirable effects on the biomechanics of gait through increased foot pronation. This study investigated the effects of increased unilateral foot pronation on the biomechanics of individuals with knee osteoarthritis during gait. Biomechanical data of twenty individuals with knee osteoarthritis were collected while they walked in three conditions: i) flat sandals; ii) wedged sandal on the knee osteoarthritis limb and flat sandal on the healthy limb; and iii) flat sandal on the osteoarthritis and wedged sandal on the healthy limb. Knee pain and comfort were evaluated. Principal Component Analysis followed by ANOVA was implemented to identify differences between conditions. The wedged sandal on the osteoarthritis limb increased rearfoot eversion (P<0.001; ES=0.79); increased shank rotation range of motion (P<0.001; ES=0.70); reduced knee internal rotation moment (P<0.001; ES=0.83); reduced hip internal rotation moment (P=0.001; ES=0.66); increased ipsilateral trunk lean (P=0.031; ES=0.47); and increased trunk rotation range of motion (P=0.001; ES=0.69). Walking with the wedged sandal on the healthy limb increased hip (P=0.003; ES=0.61) and knee (P=0.002; ES=0.63) adduction moments. Individuals reported greater comfort walking with the flat sandals (P=0.004; ES=0.55). Increased unilateral foot pronation of the knee osteoarthritis and healthy limbs causes lower limb and trunk mechanical changes that may overload the knee and the lower back, such as increased knee adduction moment, shank rotation and trunk lateral lean. Foot motion of both lower limbs should be evaluated and care must be taken when suggesting lateral wedges for individuals with knee osteoarthritis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Gait and Lower Limb Observation of Paediatrics (GALLOP): development of a consensus based paediatric podiatry and physiotherapy standardised recording proforma.

PubMed

Cranage, Simone; Banwell, Helen; Williams, Cylie M

2016-01-01

Paediatric gait and lower limb assessments are frequently undertaken in podiatry and physiotherapy clinical practice and this is a growing area of expertise within Australia. No concise paediatric standardised recording proforma exists to assist clinicians in clinical practice. The aim of this study was to develop a gait and lower limb standardised recording proforma guided by the literature and consensus, for assessment of the paediatric foot and lower limb in children aged 0-18 years. Expert Australian podiatrists and physiotherapists were invited to participate in a three round Delphi survey panel using the online Qualtrics(©) survey platform. The first round of the survey consisted of open-ended questions on paediatric gait and lower limb assessment developed from existing templates and a literature search of standardised lower limb assessment methods. Rounds two and three consisted of statements developed from the first round responses. Questions and statements were included in the final proforma if 70 % or more of the participants indicated consensus or agreement with the assessment method and if there was support within the literature for paediatric age-specific normative data with acceptable reliability of outcome measures. There were 17 of the 21 (81 %) participants who completed three rounds of the survey. Consensus was achieved for 41 statements in Round one, 54 statements achieved agreement in two subsequent rounds. Participants agreed on 95 statements relating to birth history, developmental history, hip measurement, rotation of the lower limb, ankle range of motion, foot posture, balance and gait. Assessments with acceptable validity and reliability were included within the final Gait and Lower Limb Observation of Paediatrics (GALLOP) proforma. The GALLOP proforma is a consensus based, systematic and standardised way to collect information and outcome measures in paediatric lower limb assessment. This standardised recording proforma will assist professions to collect information in a standardised format based on best evidence assessment methods whilst aiding consistency in communication between health professionals.

Kinematics in the terminal swing phase of unilateral transfemoral amputees: microprocessor-controlled versus swing-phase control prosthetic knees.

PubMed

Mâaref, Khaled; Martinet, Noël; Grumillier, Constance; Ghannouchi, Slaheddine; André, Jean Marie; Paysant, Jean

2010-06-01

To analyze the spatiotemporal parameters in the terminal swing phase of the prosthetic limb in unilateral transfemoral amputees (TFAs) compared with a group of asymptomatic subjects, and to identify a latency period (LP) in the TFA between the full extension of the prosthetic knee and the initial ground contact of the ipsilateral foot. To study the correlation between the LP and the duration of the swing phase. To evaluate the influence of the type of knee, the time since amputation, and the amputation level on the latency period. Three-dimensional gait analysis with an optoelectronic device. Gait analysis laboratory of a re-education and functional rehabilitation service. TFA (n=29) and able-bodied (n=15) subjects. Not applicable. Spatiotemporal and kinematics gait parameters. The swing phase and the LP of the prosthetic limb, associated with a consequently longer single-limb stance phase in the intact limb, were significantly longer than those measured in the intact limbs of these subjects, as well as those measured on both lower limbs of the able-bodied subjects (P<.05). There is a positive correlation (P<.05; r(2)=.58 between the LP and the swing phase on the TFA's prosthetic side. The LP measured in the prosthetic limb of TFA with a swing-phase control prosthetic knee is significantly greater than in those using the microprocessor-controlled prosthetic knee (P<.05). Of negligible duration in able-bodied subjects and in the intact limb of TFA, the LP is significantly greater in the prosthetic limb. It can explain the lengthened swing phase on the prosthetic side of those subjects. The use of a microprocessor-controlled prosthetic knee allows the LP to be reduced. This LP appears to be necessary to insure the stability of the prosthetic knee. We suggest calling this time "confidence time." Copyright 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Research Priorities in Limb and Task-Specific Dystonias.

PubMed

Pirio Richardson, Sarah; Altenmüller, Eckart; Alter, Katharine; Alterman, Ron L; Chen, Robert; Frucht, Steven; Furuya, Shinichi; Jankovic, Joseph; Jinnah, H A; Kimberley, Teresa J; Lungu, Codrin; Perlmutter, Joel S; Prudente, Cecília N; Hallett, Mark

2017-01-01

Dystonia, which causes intermittent or sustained abnormal postures and movements, can present in a focal or a generalized manner. In the limbs, focal dystonia can occur in either the upper or lower limbs and may be task-specific causing abnormal motor performance for only a specific task, such as in writer's cramp, runner's dystonia, or musician's dystonia. Focal limb dystonia can be non-task-specific and may, in some circumstances, be associated with parkinsonian disorders. The true prevalence of focal limb dystonia is not known and is likely currently underestimated, leaving a knowledge gap and an opportunity for future research. The pathophysiology of focal limb dystonia shares some commonalities with other dystonias with a loss of inhibition in the central nervous system and a loss of the normal regulation of plasticity, called homeostatic plasticity. Functional imaging studies revealed abnormalities in several anatomical networks that involve the cortex, basal ganglia, and cerebellum. Further studies should focus on distinguishing cause from effect in both physiology and imaging studies to permit focus on most relevant biological correlates of dystonia. There is no specific therapy for the treatment of limb dystonia given the variability in presentation, but off-label botulinum toxin therapy is often applied to focal limb and task-specific dystonia. Various rehabilitation techniques have been applied and rehabilitation interventions may improve outcomes, but small sample size and lack of direct comparisons between methods to evaluate comparative efficacy limit conclusions. Finally, non-invasive and invasive therapeutic modalities have been explored in small studies with design limitations that do not yet clearly provide direction for larger clinical trials that could support new clinical therapies. Given these gaps in our clinical, pathophysiologic, and therapeutic knowledge, we have identified priorities for future research including: the development of diagnostic criteria for limb dystonia, more precise phenotypic characterization and innovative clinical trial design that considers clinical heterogeneity, and limited available number of participants.

Associated reactions during a visual pursuit position tracking task in hemiplegic and quadriplegic cerebral palsy.

PubMed

Chiu, Hsiu-Ching; Halaki, Mark; O'Dwyer, Nicholas

2013-04-30

Most previous studies of associated reactions (ARs) in people with cerebral palsy have used observation scales, such as recording the degree of movement through observation. The sensitive quantitative method can detect ARs that are not amply visible. The aim of this study was to provide quantitative measures of ARs during a visual pursuit position tracking task. Twenty-three hemiplegia (H) (mean +/- SD: 21y 8m +/- 11y 10m), twelve quadriplegia (Q) (21y 5m +/- 10y 3m) and twenty-two subjects with normal development (N) (21y 2m +/- 10y 10m) participated in the study. An upper limb visual pursuit tracking task was used to study ARs. The participants were required to follow a moving target with a response cursor via elbow flexion and extension movements. The occurrence of ARs was quantified by the overall coherence between the movements of tracking and non-tracking limbs and the amount of movement due to ARs was quantified by the amplitude of movement the non-tracking limbs. The amplitude of movement of the non-tracking limb indicated that the amount of ARs was larger in the Q group than the H and N groups with no significant differences between the H and N groups. The amplitude of movement of the non-tracking limb was larger during non-dominant than dominant tracking in all three groups. Some movements in the non-tracking limb were correlated with the tracking limb (correlated ARs) and some movements that were not correlated with the tracking limb (uncorrelated ARs). The correlated ARs comprised less than 40% of the total ARs for all three groups. Correlated ARs were negatively associated with clinical evaluations, but not the uncorrelated ARs. The correlated and uncorrelated ARs appear to have different relationships with clinical evaluations, implying the effect of ARs on upper limb activities could be varied.

Research Priorities in Limb and Task-Specific Dystonias

PubMed Central

Pirio Richardson, Sarah; Altenmüller, Eckart; Alter, Katharine; Alterman, Ron L.; Chen, Robert; Frucht, Steven; Furuya, Shinichi; Jankovic, Joseph; Jinnah, H. A.; Kimberley, Teresa J.; Lungu, Codrin; Perlmutter, Joel S.; Prudente, Cecília N.; Hallett, Mark

2017-01-01

Dystonia, which causes intermittent or sustained abnormal postures and movements, can present in a focal or a generalized manner. In the limbs, focal dystonia can occur in either the upper or lower limbs and may be task-specific causing abnormal motor performance for only a specific task, such as in writer’s cramp, runner’s dystonia, or musician’s dystonia. Focal limb dystonia can be non-task-specific and may, in some circumstances, be associated with parkinsonian disorders. The true prevalence of focal limb dystonia is not known and is likely currently underestimated, leaving a knowledge gap and an opportunity for future research. The pathophysiology of focal limb dystonia shares some commonalities with other dystonias with a loss of inhibition in the central nervous system and a loss of the normal regulation of plasticity, called homeostatic plasticity. Functional imaging studies revealed abnormalities in several anatomical networks that involve the cortex, basal ganglia, and cerebellum. Further studies should focus on distinguishing cause from effect in both physiology and imaging studies to permit focus on most relevant biological correlates of dystonia. There is no specific therapy for the treatment of limb dystonia given the variability in presentation, but off-label botulinum toxin therapy is often applied to focal limb and task-specific dystonia. Various rehabilitation techniques have been applied and rehabilitation interventions may improve outcomes, but small sample size and lack of direct comparisons between methods to evaluate comparative efficacy limit conclusions. Finally, non-invasive and invasive therapeutic modalities have been explored in small studies with design limitations that do not yet clearly provide direction for larger clinical trials that could support new clinical therapies. Given these gaps in our clinical, pathophysiologic, and therapeutic knowledge, we have identified priorities for future research including: the development of diagnostic criteria for limb dystonia, more precise phenotypic characterization and innovative clinical trial design that considers clinical heterogeneity, and limited available number of participants. PMID:28515706

A comparison of hemisphere-specific training pattern in Inter-limb Learning Transfer (ILT) for stroke patients with hemiparesis.

PubMed

Yoo, In-gyu; Jung, Min-ye; Yoo, Eun-young; Park, Ji-hyuk; Kang, Dae-hyuk; Lee, Jin

2014-01-01

Stroke patients have major problems with impaired upper-extremity function. Unfortunately, many patients do not experience a full recovery from movement deficits in the upper extremities. The purpose of this study was to compare the effectiveness of inter-limb learning transfer (ILT) to the contralateral upper limb after both hemisphere-specific and -unspecific ipsilateral upper limb training for stroke patients with hemiparesis. Twenty-four stroke patients with hemiparesis participated. The hemisphere-specific training group performed reaching movements in a customized training setting in which non-dominant limb training participants began from a single starting location and proceeded to one of three target locations (1S3T condition); the dominant limb training participants started from one of three starting locations and proceeded to a single target location (3S1T condition). The hemisphere-unspecific training group performed these movements starting under reverse-start and target conditions. The non-dominant to dominant limb transfer, the hemisphere-specific training group performance time decreased significantly as compared with the pre-training session (p < 0.05). Also, the isolation contraction ratio was decreased significantly from that of the pre-training session in the biceps brachii muscles and increased significantly in the upper trapezius muscles (p < 0.05). And, dominant to non-dominant limb transfer in the hemisphere-specific training group significantly increased RMS amplitudes from the pre-training session in the biceps brachii and triceps muscles (p < 0.05). Also, the isolation contraction ratio was increased significantly from that of the pre-training session in the biceps brachii muscles and decreased significantly in the upper trapezius muscles (p < 0.05). However, the hemisphere-unspecific training group showed no significant differences in inter-limb learning transfer (ILT). The transfer of hemisphere-specific training from one arm to the other had a more positive influence on functional recovery than did hemisphere-unspecific training for patients with stroke and hemiparesis.

Modelling the effect of race surface and racehorse limb parameters on in silico fetlock motion and propensity for injury.

PubMed

Symons, J E; Hawkins, D A; Fyhrie, D P; Upadhyaya, S K; Stover, S M

2017-09-01

The metacarpophalangeal joint (fetlock) is the most commonly affected site of racehorse injury, with multiple observed pathologies consistent with extreme fetlock dorsiflexion. Race surface mechanics affect musculoskeletal structure loading and injury risk because surface forces applied to the hoof affect limb motions. Race surface mechanics are a function of controllable factors. Thus, race surface design has the potential to reduce the incidence of musculoskeletal injury through modulation of limb motions. However, the relationship between race surface mechanics and racehorse limb motions is unknown. To determine the effect of changing race surface and racehorse limb model parameters on distal limb motions. Sensitivity analysis of in silico fetlock motion to changes in race surface and racehorse limb parameters using a validated, integrated racehorse and race surface computational model. Fetlock motions were determined during gallop stance from simulations on virtual surfaces with differing average vertical stiffness, upper layer (e.g. cushion) depth and linear stiffness, horizontal friction, tendon and ligament mechanics, as well as fetlock position at heel strike. Upper layer depth produced the greatest change in fetlock motion, with lesser depths yielding greater fetlock dorsiflexion. Lesser fetlock changes were observed for changes in lower layer (e.g. base or pad) mechanics (nonlinear), as well as palmar ligament and tendon stiffness. Horizontal friction and fetlock position contributed less than 1° change in fetlock motion. Simulated fetlock motions are specific to one horse's anatomy reflected in the computational model. Anatomical differences among horses may affect the magnitude of limb flexion, but will likely have similar limb motion responses to varied surface mechanics. Race surface parameters affected by maintenance produced greater changes in fetlock motion than other parameters studied. Simulations can provide evidence to inform race surface design and management to reduce the incidence of injury. © 2017 EVJ Ltd.

Incidence rate of mild traumatic brain injury among patients who have suffered from an isolated limb fracture: Upper limb fracture patients are more at risk.

PubMed

Jodoin, Marianne; Rouleau, Dominique M; Charlebois-Plante, Camille; Benoit, Benoit; Leduc, Stéphane; Laflamme, G-Yves; Gosselin, Nadia; Larson-Dupuis, Camille; De Beaumont, Louis

2016-08-01

This study compares the incidence rate of mild traumatic brain injury (mild TBI) detected at follow-up visits (retrospective diagnosis) in patients suffering from an isolated limb trauma, with the incidence rate held by the hospital records (prospective diagnosis) of the sampled cohort. This study also seeks to determine which types of fractures present with the highest incidence of mild TBI. Retrospective assessment of mild TBI among orthopaedic monotrauma patients, randomly selected for participation in an Orthopaedic clinic of a Level I Trauma Hospital. Patients in the remission phase of a limb fracture were recruited between August 2014 and May 2015. No intervention was done (observational study). Standardized semi-structured interviews were conducted with all patients to retrospectively assess for mild TBI at the time of the fracture. Emergency room related medical records of all patients were carefully analyzed to determine whether a prospective mild TBI diagnosis was made following the accident. A total of 251 patients were recruited (54% females, Mean age=49). Study interview revealed a 23.5% incidence rate of mild TBI compared to an incidence rate of 8.8% for prospective diagnosis (χ(2)=78.47; p<0.0001). Patients suffering from an upper limb monotrauma (29.6%; n=42/142) are significantly more at risk of sustaining a mild TBI compared to lower limb fractures (15.6%; n=17/109) (χ(2)=6.70; p=0.010). More specifically, patients with a proximal upper limb injury were significantly more at risk of sustaining concomitant mild TBI (40.6%; 26/64) compared to distal upper limb fractures (20.25%; 16/79) (χ(2)=7.07; p=0.008). Results suggest an important concomitance of mild TBI among orthopaedic trauma patients, the majority of which go undetected during acute care. Patients treated for an upper limb fracture are particularly at risk of sustaining concomitant mild TBI. Copyright © 2016 Elsevier Ltd. All rights reserved.

Immunomodulation to Optimize Vascularized Composite Allograft Integration in Limb Loss Therapy

DTIC Science & Technology

2015-10-01

2 AWARD  NUMBER:        W81XWH-­12-­2-­0058   TITLE:      Immunomodulation to Optimize Vascularized Composite Allograft Integration in Limb Loss...NUMBER   Immunomodulation to Optimize Vascularized Composite Allograft Integration in Limb Loss Therapy 5b.  GRANT  NUMBER   W81XWH-­12-­2-­0058...transplanted   tissues  are  now  available   that  may  greatly   reduce   the   risks  associated   with  limb  transplantation.       The  proposal

Periodic limb movements and insomnia, a common but under-recognized association

PubMed Central

Varadharajulu, Saravanan; Chandrasekaran, Baskaran

2015-01-01

Periodic limb movements unlike restless leg syndrome is under diagnosed and unrecognized in medical arena. While robust Western trials have elucidated the association between periodic limb movements and sleep disturbances, it is not well received and recognized in India even in well sophisticated tertiary care hospital. We report a chronic insomnia patient who had sleep disturbances for past 30 years due to periodic limb movements alone. This was diagnosed through polysomnography. This case emphasizes monitoring leg movements during sleep study. This report may open new horizons in improving monitoring in sleep study in clinical setting. PMID:26124530

Case report of a high voltage electrical injury and review of the indications for early fasciotomy in limb salvage of an electrically injured limb

PubMed Central

Huei, T.J.; Mohd Yussof, S.J.; Lip, H.T.C.; Salina, I.

2017-01-01

Summary Electrical injuries make up a relatively small portion of burn injuries. Safety measures in place on domestic electricity supply have reduced the occurrence of high voltage electrical injuries. We present the case of a young man who sustained a high voltage electrical injury on all four limbs. Early fasciotomy was performed on both his hands and forearms. Despite early compartment release, the left upper limb deteriorated and required amputation. In this article we discuss the indications, outcomes and complications of early fasciotomy. PMID:29021730

Congenital Limb Deficiency Associated with Intellectual Disability: Unusual Presentation in Two Subjects.

PubMed

Raza, Muhammad Ummear; Ullah, Waheed; Malik, Sajid

2016-09-01

Congenital constriction ring (CCR) and symbrachydactyly are two distinct, rare, and heterogeneous limb deficiency conditions which affect the digits. Here, we report on two different individuals with an unusual presentation of limb deficiency accompanying intellectual disability (ID) and certain other malformations. In the first index female, CCR occurred with mild ID, squint eyes, obesity, and metatarsus adductus. The second index male was presented with symbrachydactyly, profound ID, and speech/hearing impairments. The association of limb deficiency conditions with these anomalies is very rare. Differential diagnosis and literature survey have been offered to establish the rarity of these entities.

A newborn with unilateral limb enlargement.

PubMed

Sharma, Shanel; Maino, Anna P F; Husain, Shad M; Adams, Gill G W

2012-03-01

On routine neonatal examination, a newborn term male was noted to have unilateral enlargement of the right lower limb, loose thickened red skin over the palm and widening of all the fingers on the right hand. His body was pinker and warmer on the right side compared with the left and he had a right undescended testicle and hypoplastic scrotum. Radiological examination of the lower limbs demonstrated the enlargement of the soft tissue of the right lower limb compared to the left (Fig. 1). Therefore, the diagnosis was unclear from this constellation of findings and an ophthalmic assessment was requested.

Limb-darkening and the structure of the Jovian atmosphere

NASA Technical Reports Server (NTRS)

Newman, W. I.; Sagan, C.

1978-01-01

By observing the transit of various cloud features across the Jovian disk, limb-darkening curves were constructed for three regions in the 4.6 to 5.1 mu cm band. Several models currently employed in describing the radiative or dynamical properties of planetary atmospheres are here examined to understand their implications for limb-darkening. The statistical problem of fitting these models to the observed data is reviewed and methods for applying multiple regression analysis are discussed. Analysis of variance techniques are introduced to test the viability of a given physical process as a cause of the observed limb-darkening.

The Quest toward limb regeneration: a regenerative engineering approach

PubMed Central

Laurencin, Cato T.; Nair, Lakshmi S.

2016-01-01

The Holy Grail to address the clinical grand challenge of human limb loss is to develop innovative strategies to regrow the amputated limb. The remarkable advances in the scientific understanding of regeneration, stem cell science, material science and engineering, physics and novel surgical approaches in the past few decades have provided a regenerative tool box to face this grand challenge and address the limitations of human wound healing. Here we discuss the convergence approach put forward by the field of Regenerative Engineering to use the regenerative tool box to design and develop novel translational strategies to limb regeneration. PMID:27047679

Crouch gait can be an effective form of forced-use/no constraint exercise for the paretic lower limb in stroke.

PubMed

Tesio, Luigi; Rota, Viviana; Malloggi, Chiara; Brugliera, Luigia; Catino, Luigi

2017-09-01

In hemiplegic gait the paretic lower limb provides less muscle power and shows a briefer stance compared with the unaffected limb. Yet, a longer stance and a higher power can be obtained from the paretic lower limb if gait speed is increased. This supports the existence of a 'learned non-use' phenomenon, similar to that underlying some asymmetric impairments of the motion of the eyes and of the upper limbs. Crouch gait (CG) (bent-hip bent-knee, about 30° minimum knee flexion) might be an effective form of 'forced-use' treatment of the paretic lower limb. It is not known whether it also stimulates a more symmetric muscle power output. Gait analysis on a force treadmill was carried out in 12 healthy adults and seven hemiplegic patients (1-127 months after stroke, median: 1.6). Speed was imposed at 0.3 m/s. Step length and single and double stance times, sagittal joint rotations, peak positive power, and work in extension of the hip, knee, and ankle (plantar flexion), and surface electromyography (sEMG) area from extensor muscles during the generation of power were measured on either side during both erect and crouch walking. Significance was set at P less than 0.05; corrections for multiplicity were applied. Patients, compared with healthy controls, adopted in both gait modalities and on both sides a shorter step length (61-84%) as well as a shorter stance (76-90%) and swing (63-83%) time. As a rule, they also provided a higher muscular work (median: 137%, range: 77-250%) paralleled by a greater sEMG area (median: 174%, range: 75-185%). In erect gait, the generation of peak extensor power across hip, knee, and ankle joints was in general lower (83-90%) from the paretic limb and higher (98-165%) from the unaffected limb compared with control values. In CG, peak power generation across the three lower limb joints was invariably higher in hemiparetic patients: 107-177% from the paretic limb and 114-231% from the unaffected limb. When gait shifted from erect to crouch, only for hemiplegic patients, at the hip, the paretic/unaffected ratio increased significantly. For peak power, work, sEMG area, and joint rotation, the paretic/unaffected ratio increased from 55 to 85%, 56 to 72%, 68 to 91%, and 67 to 93%, respectively. CG appears to be an effective form of forced-use exercise eliciting more power and work from the paretic lower limb muscles sustained by a greater neural drive. It also seems effective in forcing a more symmetric power and work from the hip extensor muscles, but neither from the knee nor the ankle.

Adaptive behaviour and motor skills in children with upper limb deficiency.

PubMed

Mano, Hiroshi; Fujiwara, Sayaka; Haga, Nobuhiko

2018-04-01

The dysfunction of individuals with upper limb deficiencies affects their daily lives and social participation. To clarify the adaptive behaviours and motor skills of children with upper limb deficiencies. Cross-sectional survey. The subjects were 10 children ranging from 1 to 6 years of age with unilateral upper limb deficiencies at the level distal to the elbow who were using only cosmetic or passive prostheses or none at all. To measure their adaptive behaviour and motor skills, the Vineland Adaptive Behavior Scales, Second Edition was used. They were evaluated on the domains of communication, daily living skills, socialization and motor skills. We also examined the relationship of the scores with age. There were no statistically significant scores for domains or subdomains. The domain standard score of motor skills was significantly lower than the median scores of the domains and was negatively correlated with age. Children with upper limb deficiencies have individual weaknesses in motor skill behaviours, and these weaknesses increase with age. It may be helpful in considering approaches to rehabilitation and the prescription of prostheses to consider the characteristics and course of children's motor skill behaviours. Clinical relevance Even if children with unilateral upper limb deficiencies seem to compensate well for their affected limb function, they have or will experience individual weaknesses in motor skills. We should take this into consideration to develop better strategies for rehabilitation and prostheses prescriptions.

Proximity to Pollution Sources and Risk of Amphibian Limb Malformation

PubMed Central

Taylor, Brynn; Skelly, David; Demarchis, Livia K.; Slade, Martin D.; Galusha, Deron; Rabinowitz, Peter M.

2005-01-01

The cause of limb deformities in wild amphibian populations remains unclear, even though the apparent increase in prevalence of this condition may have implications for human health. Few studies have simultaneously assessed the effect of multiple exposures on the risk of limb deformities. In a cross-sectional survey of 5,264 hylid and ranid metamorphs in 42 Vermont wetlands, we assessed independent risk factors for nontraumatic limb malformation. The rate of nontraumatic limb malformation varied by location from 0 to 10.2%. Analysis of a subsample did not demonstrate any evidence of infection with the parasite Ribeiroia. We used geographic information system (GIS) land-use/land-cover data to validate field observations of land use in the proximity of study wetlands. In a multiple logistic regression model that included land use as well as developmental stage, genus, and water-quality measures, proximity to agricultural land use was associated with an increased risk of limb malformation (odds ratio = 2.26; 95% confidence interval, 1.42–3.58; p < 0.001). The overall discriminant power of the statistical model was high (C = 0.79). These findings from one of the largest systematic surveys to date provide support for the role of chemical toxicants in the development of amphibian limb malformation and demonstrate the value of an epidemiologic approach to this problem. PMID:16263502

Contribution of limb momentum to power transfer in athletic wheelchair pushing.

PubMed

Masson, G; Bégin, M-A; Lopez Poncelas, M; Pelletier, S-K; Lessard, J-L; Laroche, J; Berrigan, F; Langelier, E; Smeesters, C; Rancourt, D

2016-09-06

Pushing capacity is a key parameter in athletic racing wheelchair performance. This study estimated the potential contribution of upper limb momentum to pushing. The question is relevant since it may affect the training strategy adopted by an athlete. A muscle-free Lagrangian dynamic model of the upper limb segments was developed and theoretical predictions of power transfer to the wheelchair were computed during the push phase. Results show that limb momentum capacity for pushing can be in the order of 40J per push cycle at 10m/s, but it varies with the specific pushing range chosen by the athlete. Although use of momentum could certainly help an athlete improve performance, quantifying the actual contribution of limb momentum to pushing is not trivial. A preliminary experimental investigation on an ergometer, along with a simplified model of the upper limb, suggests that momentum is not the sole contributor to power transfer to a wheelchair. Muscles substantially contribute to pushing, even at high speeds. Moreover, an optimal pushing range is challenging to find since it most likely differs if an athlete chooses a limb momentum pushing strategy versus a muscular exertion pushing strategy, or both at the same time. The study emphasizes the importance of controlling pushing range, although one should optimize it while also taking the dynamics of the recovery period into account. Copyright © 2016 Elsevier Ltd. All rights reserved.

Biomechanical response to ankle-foot orthosis stiffness during running.

PubMed

Russell Esposito, Elizabeth; Choi, Harmony S; Owens, Johnny G; Blanck, Ryan V; Wilken, Jason M

2015-12-01

The Intrepid Dynamic Exoskeletal Orthosis (IDEO) is an ankle-foot orthosis developed to address the high rates of delayed amputation in the military. Its use has enabled many wounded Service Members to run again. During running, stiffness is thought to influence an orthosis' energy storage and return mechanical properties. This study examined the effect of orthosis stiffness on running biomechanics in patients with lower limb impairments who had undergone unilateral limb salvage. Ten patients with lower limb impairments underwent gait analysis at a self-selected running velocity. 1. Nominal (clinically-prescribed), 2. Stiff (20% stiffer than nominal), and 3. Compliant (20% less stiff than nominal) ankle-foot orthosis stiffnesses were tested. Ankle joint stiffness was greatest in the stiffest strut and lowest in the compliant strut, however ankle mechanical work remained unchanged. Speed, stride length, cycle time, joint angles, moments, powers, and ground reaction forces were not significantly different among stiffness conditions. Ankle joint kinematics and ankle, knee and hip kinetics were different between limbs. Ankle power, in particular, was lower in the injured limb. Ankle-foot orthosis stiffness affected ankle joint stiffness but did not influence other biomechanical parameters of running in individuals with unilateral limb salvage. Foot strike asymmetries may have influenced the kinetics of running. Therefore, a range of stiffness may be clinically appropriate when prescribing ankle-foot orthoses for active individuals with limb salvage. Published by Elsevier Ltd.

Two-dimensional radiative transfer for the retrieval of limb emission measurements in the martian atmosphere

NASA Astrophysics Data System (ADS)

Kleinböhl, Armin; Friedson, A. James; Schofield, John T.

2017-01-01

The remote sounding of infrared emission from planetary atmospheres using limb-viewing geometry is a powerful technique for deriving vertical profiles of structure and composition on a global scale. Compared with nadir viewing, limb geometry provides enhanced vertical resolution and greater sensitivity to atmospheric constituents. However, standard limb profile retrieval techniques assume spherical symmetry and are vulnerable to biases produced by horizontal gradients in atmospheric parameters. We present a scheme for the correction of horizontal gradients in profile retrievals from limb observations of the martian atmosphere. It characterizes horizontal gradients in temperature, pressure, and aerosol extinction along the line-of-sight of a limb view through neighboring measurements, and represents these gradients by means of two-dimensional radiative transfer in the forward model of the retrieval. The scheme is applied to limb emission measurements from the Mars Climate Sounder instrument on Mars Reconnaissance Orbiter. Retrieval simulations using data from numerical models indicate that biases of up to 10 K in the winter polar region, obtained with standard retrievals using spherical symmetry, are reduced to about 2 K in most locations by the retrieval with two-dimensional radiative transfer. Retrievals from Mars atmospheric measurements suggest that the two-dimensional radiative transfer greatly reduces biases in temperature and aerosol opacity caused by observational geometry, predominantly in the polar winter regions.

Upper limb contributions to frontal plane balance control in rollator-assisted walking.

PubMed

Tung, James Y; Gage, William H; Poupart, Pascal; McIlroy, William E

2014-01-01

While assisting with balance is a primary reason for rollator use, few studies have examined how the upper limbs are used for balance. This study examines upper limb contributions to balance control during rollator-assisted walking. We hypothesized that there would be an increased upper limb contribution, measured by mean vertical loading (Fz) and variation in frontal plane center-of-pressure (COPhigh), when walking balance is challenged/impaired. Experiment 1 compared straight-line and beam-walking in young adults (n = 11). As hypothesized, Fz and COPhighincreased in beam-walking compared to baseline (mean Fz: 13.7 vs. 9.1% body weight (BW), p < 0.001, RMS COPhigh: 1.35 vs. 1.07 cm, p < 0.001). Experiment 2 compared older adults who regularly use rollators (RU, n = 10) to older adult controls (CTL, n = 10). The predicted higher upper limb contribution in the RU group was not supported. However, when individuals were grouped by balance impairment, those with the lowest Berg Balance scores (< 45) demonstrated greater speed-adjusted COPhigh than those with higher scores (p = 0.013). Furthermore, greater COPhigh and Fz were correlated to greater reduction in step width, supporting the role of upper limb contributions to frontal plane balance. This work will guide studies assessing reliance on rollators by providing a basis for measurement of upper limb balance contributions.

Limb-Enhancer Genie: An accessible resource of accurate enhancer predictions in the developing limb

DOE PAGES

Monti, Remo; Barozzi, Iros; Osterwalder, Marco; ...

2017-08-21

Epigenomic mapping of enhancer-associated chromatin modifications facilitates the genome-wide discovery of tissue-specific enhancers in vivo. However, reliance on single chromatin marks leads to high rates of false-positive predictions. More sophisticated, integrative methods have been described, but commonly suffer from limited accessibility to the resulting predictions and reduced biological interpretability. Here we present the Limb-Enhancer Genie (LEG), a collection of highly accurate, genome-wide predictions of enhancers in the developing limb, available through a user-friendly online interface. We predict limb enhancers using a combination of > 50 published limb-specific datasets and clusters of evolutionarily conserved transcription factor binding sites, taking advantage ofmore » the patterns observed at previously in vivo validated elements. By combining different statistical models, our approach outperforms current state-of-the-art methods and provides interpretable measures of feature importance. Our results indicate that including a previously unappreciated score that quantifies tissue-specific nuclease accessibility significantly improves prediction performance. We demonstrate the utility of our approach through in vivo validation of newly predicted elements. Moreover, we describe general features that can guide the type of datasets to include when predicting tissue-specific enhancers genome-wide, while providing an accessible resource to the general biological community and facilitating the functional interpretation of genetic studies of limb malformations.« less

Development of five digits is controlled by a bipartite long-range cis-regulator.

PubMed

Lettice, Laura A; Williamson, Iain; Devenney, Paul S; Kilanowski, Fiona; Dorin, Julia; Hill, Robert E

2014-04-01

Conservation within intergenic DNA often highlights regulatory elements that control gene expression from a long range. How conservation within a single element relates to regulatory information and how internal composition relates to function is unknown. Here, we examine the structural features of the highly conserved ZRS (also called MFCS1) cis-regulator responsible for the spatiotemporal control of Shh in the limb bud. By systematically dissecting the ZRS, both in transgenic assays and within in the endogenous locus, we show that the ZRS is, in effect, composed of two distinct domains of activity: one domain directs spatiotemporal activity but functions predominantly from a short range, whereas a second domain is required to promote long-range activity. We show further that these two domains encode activities that are highly integrated and that the second domain is crucial in promoting the chromosomal conformational changes correlated with gene activity. During limb bud development, these activities encoded by the ZRS are interpreted differently by the fore limbs and the hind limbs; in the absence of the second domain there is no Shh activity in the fore limb, and in the hind limb low levels of Shh lead to a variant digit pattern ranging from two to four digits. Hence, in the embryo, the second domain stabilises the developmental programme providing a buffer for SHH morphogen activity and this ensures that five digits form in both sets of limbs.

B-mode and power Doppler ultrasonography of the equine suspensory ligament branches: A descriptive study on 13 horses.

PubMed

Rabba, Silvia; Grulke, Sigrid; Verwilghen, Denis; Evrard, Laurence; Busoni, Valeria

2018-03-01

Ultrasonography is routinely used to achieve the diagnosis of equine suspensory ligament desmopathy. In human medicine, power Doppler ultrasonography has also been found to be useful for the diagnosis of tendon/ligament injuries. The aim of this prospective, pilot study was to assess the presence or absence of power Doppler signal in suspensory ligament branches and compare B-mode findings with power Doppler findings in suspensory ligament branches of lame and non-lame limbs. Thirteen horses were used (eight lame horses, with lameness related to pain in the suspensory ligament branches, and five non-lame horses). Ten lame limbs and 24 sound limbs were assessed by B-mode and power Doppler ultrasonography. The severity of power Doppler signal was scored by two independent readers. The B-mode ultrasonographic examination revealed abnormalities in branches of lame limbs and in branches of sound limbs. Suspensory ligament branches that were considered normal in B-mode showed no power Doppler signal. However, power Doppler signal was detected in suspensory ligament branches that were abnormal in B-mode, both in lame and sound limbs. Power Doppler scores were subjectively higher in suspensory ligament branches of lame limbs and in branches with more severe B-mode changes. Findings supported the use of power Doppler as an adjunctive diagnostic test for lame horses with suspected suspensory desmopathy. © 2018 American College of Veterinary Radiology.

Electromyography-based analysis of human upper limbs during 45-day head-down bed-rest

NASA Astrophysics Data System (ADS)

Fu, Anshuang; Wang, Chunhui; Qi, Hongzhi; Li, Fan; Wang, Zheng; He, Feng; Zhou, Peng; Chen, Shanguang; Ming, Dong

2016-03-01

Muscle deconditioning occurs in response to simulated or actual microgravity. In spaceflight, astronauts become monkey-like for mainly using their upper limbs to control the operating system and to complete corresponding tasks. The changes of upper limbs' athletic ability will directly affect astronauts' working performance. This study investigated the variation trend of surface electromyography (sEMG) during prolonged simulated microgravity. Eight healthy males participating in this study performed strict 45-day head-down bed-rest (HDBR). On the 5th day of pre-HDBR, and the 15th, the 30th and the 45th days of HDBR, the subjects performed maximum pushing task and maximum pulling task, and sEMG was collected from upper limbs synchronously. Each subject's maximum volunteer contractions of both the tasks during these days were compared, showing no significant change. However, changes were detected by sEMG-based analysis. It was found that integrated EMG, root mean square, mean frequency, fuzzy entropy of deltoid, and fuzzy entropy of triceps brachii changed significantly when comparing pre-HDBR with HDBR. The variation trend showed a recovery tendency after significant decline, which is inconsistent with the monotonic variation of lower limbs that was proved by previous research. These findings suggest that EMG changes in upper limbs during prolonged simulated microgravity, but has different variation trend from lower limbs.

Constraint-induced movement therapy for children with hemiplegia after traumatic brain injury: a quantitative study.

PubMed

Cimolin, Veronica; Beretta, Elena; Piccinini, Luigi; Turconi, Anna Carla; Locatelli, Federica; Galli, Manuela; Strazzer, Sandra

2012-01-01

The aims of this study are to quantify the movement limitation of upper limbs in hemiplegic children with traumatic brain injury (TBI) by using a clinical-functional scale and upper limb kinematics and to evaluate the effectiveness of constraint-induced movement therapy (CIMT) on upper limbs. Pre-post study. Clinical rehabilitation research laboratory. Ten children with TBI. The participants were evaluated by clinical examinations (Gross Motor Function Measure, Besta scale, Quality of Upper Extremities Skills Test, and Manual Ability Classification System) and 3D kinematic movement analysis of the upper limb before the CIMT program (pretest: 0.7 years after the injury) and at the end of the program (posttest: 10 weeks later). After the CIMT, most of the clinical measures improved significantly. Some significant improvements were present in terms of kinematics, in particular, in the movement duration and the velocity of movement execution of both tasks; the index of curvature and the average jerk improved, respectively, during reaching and hand-to-mouth task, while the adjusting sway parameter decreased during the 2 movements. Significant improvements were found in upper limb joint excursion after the rehabilitative programme too. Our results suggest that the CIMT program can improve movement efficiency and upper limb function in children after TBI. The integration of the clinical outcomes and upper limb kinematics revealed to be crucial in detecting the effects of the CIMT programme.

EFFICACY of P188 ON LAPINE MENISCUS PRESERVATION FOLLOWING BLUNT TRAUMA

PubMed Central

Coatney, Garrett A.; Abraham, Adam C.; Fischenich, Kristine M.; Button, Keith D.; Haut, Roger C.; Haut Donahue, Tammy L.

2015-01-01

Traumatic injury to the knee leads to the development of posttraumatic osteoarthritis. The objective of this study was to characterize the effects of a single intra-articular injection of a non-ionic surfactant, Poloxamer 188 (P188), in preservation of meniscal tissue following trauma through maintenance of meniscal glycosaminoglycan (GAG) content and mechanical properties. Flemish Giant rabbits were subjected to a closed knee joint, traumatic compressive impact with the joint constrained to prevent anterior tibial translation. The contralateral limb served as an un-impacted control. Six animals (treated) received an injection of P188 in phosphate buffered saline (PBS) post trauma, and another six animals (sham) received a single injection of PBS to the impacted limb. Histological analyses for GAG was determined 6 weeks post trauma, and functional outcomes were assessed using stress relaxation micro-indentation. The impacted limbs of the sham group demonstrated a significant decrease in meniscal GAG coverage compared to non-impacted limbs (p < 0.05). GAG coverage of the impacted P188 treated limbs was not significantly different than contralateral non-impacted limbs in all regions except the medial anterior (p < 0.05). No significant changes were documented in mechanics for either the sham or treated groups compared to their respective control limbs. This suggests that a single intra-articular injection of P188 shows promise in prevention of trauma induced GAG loss. PMID:25846264

Morphological Variation in Anuran Limbs: Constraints and Novelties.

PubMed

Fabrezi, Marissa; Goldberg, Javier; Chuliver Pereyra, Mariana

2017-09-01

Anurans have three primary types of locomotion: walking, jumping, and swimming. Additionally, they may dig, climb, grasp, etc. All adult anurans have four limbs, with four fingers on the hands and five toes on the feet. We summarized and updated knowledge on the interspecific variation within anuran limbs, then discuss how developmental constraints (e.g., in size) and novelties may have influenced anuran diversification through the locomotion. We analyze morphological variation from limb bud stages up to the final limb form resulting from certain skeletal organization and growth. We find limited morphometric variations in the skeleton of different developmental modules (i.e., skull, trunk, urostyle, limbs) indicate that the anuran body shape is largely constrained. We identify specializations of the stylopodium, zeugopodium, and proximal carpals/tarsals that have evolved to facilitiate saltatorial locomotion. We show that the anuran prepollex and prehallux are not vestigial digits and that they have come to serve specialized function. Medial rotation of the manus in anurans appears to have evolved to help distribute the force of impact upon landing at the end of a jump. Additional skeletal elements in anuran limbs are intercalary elements and sesamoids. The intercalary elements appear within neobatrachians and are integrated with digital pads in lineages capable of locomotion on smooth vertical surfaces. They have allowed arboreal anurans to occupy a wide range of arboreal habitats. © 2017 Wiley Periodicals, Inc.

Validation of the FACT-B+4-UL questionnaire and exploration of its predictive value in women submitted to surgery for breast cancer.

PubMed

Andrade Ortega, Juan Alfonso; Millán Gómez, Ana Pilar; Ribeiro González, Marisa; Martínez Piró, Pilar; Jiménez Anula, Juan; Sánchez Andújar, María Belén

2017-06-21

The early detection of upper limb complications is important in women operated on for breast cancer. The "FACT-B+4-UL" questionnaire, a specific variant of the Functional Assessment of Cancer Therapy-Breast (FACT-B) is available among others to measure the upper limb function. The Spanish version of the upper limb subscale of the FACT-B+4 was validated in a prospective cohort of 201 women operated on for breast cancer (factor analysis, internal consistency, test-retest reliability, construct validity and sensitivity to change were determined). Its predictive capacity of subsequent lymphoedema and other complications in the upper limb was explored using logistic regression. This subscale is unifactorial and has a great internal consistency (Cronbach's alpha: 0.87), its test-retest reliability and construct validity are strong (intraclass correlation coefficient: 0.986; Pearson's R with "Quick DASH": 0.81) as is its sensitivity to change. It didn't predict the onset of lymphedema. Its predictive capacity for other upper limb complications is low. FACT-B+4-UL is useful in measuring upper limb disability in women surgically treated for breast cancer; but it does not predict the onset of lymphoedema and its predictive capacity for others complications in the upper limb is low. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

Electromyographic and Neuromuscular Force Patterns Associated with Unexpectedly Loaded Rapid Limb Movements.

ERIC Educational Resources Information Center

Richardson, Charles; Simmons, Roger W.

Bi-articular, unidirectional arm movements were studied to evaluate the electromyographic (EMG) and neuromuscular force patterns that occur when a limb is unexpectedly perturbed. A series of training trials were continued with a control load spring attached to the apparatus until a pre-specified criterion for learning was attained. The limb was…

Improvements in Limb Kinetic Apraxia by Repetition of a Newly Designed Facilitation Exercise in a Patient with Corticobasal Degeneration

ERIC Educational Resources Information Center

Kawahira, Kazumi; Noma, Tomokazu; Iiyama, Junichi; Etoh, Seiji; Ogata, Atsuko; Shimodozono, Megumi

2009-01-01

Corticobasal degeneration is a progressive neurological disorder characterized by a combination of parkinsonism and cortical dysfunction such as limb kinetic apraxia, alien limb phenomenon, and dementia. To study the effect of repetitive facilitation exercise (RFE) in a patient with corticobasal degeneration, we used a newly designed facilitation…

Update on embryology of the upper limb.

PubMed

Al-Qattan, Mohammad M; Kozin, Scott H

2013-09-01

Current concepts in the steps of upper limb development and the way the limb is patterned along its 3 spatial axes are reviewed. Finally, the embryogenesis of various congenital hand anomalies is delineated with an emphasis on the pathogenetic basis for each anomaly. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

TES/Aura L2 Ozone (O3) Limb V6 (TL2O3LS)

Atmospheric Science Data Center

2018-03-01

TES/Aura L2 Ozone (O3) Limb (TL2O3LS) News:  TES News Join ... Project Title:  TES Discipline:  Tropospheric Composition Version:  V6 Level:  L2 Platform:  TES/Aura L2 Ozone Spatial Coverage:  27 x 23 km Limb Spatial ...

TES/Aura L2 Ozone (O3) Limb V6 (TL2O3L)

Atmospheric Science Data Center

2018-03-01

TES/Aura L2 Ozone (O3) Limb (TL2O3L) News:  TES News Join TES ... Project Title:  TES Discipline:  Tropospheric Composition Version:  V6 Level:  L2 Platform:  TES/Aura L2 Ozone Spatial Coverage:  27 x 23 km Limb Spatial ...

Specialization of the Motor System in Infancy: From Broad Tuning to Selectively Specialized Purposeful Actions

ERIC Educational Resources Information Center

D'Souza, Hana; Cowie, Dorothy; Karmiloff-Smith, Annette; Bremner, Andrew J.

2017-01-01

In executing purposeful actions, adults select sufficient and necessary limbs. But infants often move goal-irrelevant limbs, suggesting a developmental process of motor specialization. Two experiments with 9- and 12-month-olds revealed gradual decreases in extraneous movements in non-acting limbs during unimanual actions. In Experiment 1,…

49 CFR 572.20 - Limbs.

Code of Federal Regulations, 2010 CFR

2010-10-01

... OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES 3-Year-Old Child § 572.20 Limbs. The limbs consist of the assemblies shown on drawing SA 103C 001 as Nos. SA 103C 041, SA 103C 042, SA 103C 051, SA... each of the applicable drawings listed under their respective numbers of the drawing SA 103C 002...

Computational fluid dynamics evaluation of the cross-limb stent graft configuration for endovascular aneurysm repair.

PubMed

Shek, Tina L T; Tse, Leonard W; Nabovati, Aydin; Amon, Cristina H

2012-12-01

The technique of crossing the limbs of bifurcated modular stent grafts for endovascular aneurysm repair (EVAR) is often employed in the face of splayed aortic bifurcations to facilitate cannulation and prevent device kinking. However, little has been reported about the implications of cross-limb EVAR, especially in comparison to conventional EVAR. Previous computational fluid dynamics studies of conventional EVAR grafts have mostly utilized simplified planar stent graft geometries. We herein examined the differences between conventional and cross-limb EVAR by comparing their hemodynamic flow fields (i.e., in the "direct" and "cross" configurations, respectively). We also added a "planar" configuration, which is commonly found in the literature, to identify how well this configuration compares to out-of-plane stent graft configurations from a hemodynamic perspective. A representative patient's cross-limb stent graft geometry was segmented using computed tomography imaging in Mimics software. The cross-limb graft geometry was used to build its direct and planar counterparts in SolidWorks. Physiologic velocity and mass flow boundary conditions and blood properties were implemented for steady-state and pulsatile transient simulations in ANSYS CFX. Displacement forces, wall shear stress (WSS), and oscillatory shear index (OSI) were all comparable between the direct and cross configurations, whereas the planar geometry yielded very different predictions of hemodynamics compared to the out-of-plane stent graft configurations, particularly for displacement forces. This single-patient study suggests that the short-term hemodynamics involved in crossing the limbs is as safe as conventional EVAR. Higher helicity and improved WSS distribution of the cross-limb configuration suggest improved flow-related thrombosis resistance in the short term. However, there may be long-term fatigue implications to stent graft use in the cross configuration when compared to the direct configuration.

Demonstration of the test-retest reliability and sensitivity of the Lower Limb Functional Index-10 as a measure of functional recovery post burn injury: a cross-sectional repeated measures study design.

PubMed

Ryland, Margaret E; Grisbrook, Tiffany L; Wood, Fiona M; Phillips, Michael; Edgar, Dale W

2016-01-01

Lower limb burns can significantly delay recovery of function. Measuring lower limb functional outcomes is challenging in the unique burn patient population and necessitates the use of reliable and valid tools. The aims of this study were to examine the test-retest reliability, sensitivity, and internal consistency of Sections 1 and 3 of the Lower Limb Functional Index-10 (LLFI-10) questionnaire for measuring functional ability in patients with lower limb burns over time. Twenty-nine adult patients who had sustained a lower limb burn injury in the previous 12 months completed the test-retest procedure of the study. In addition, the minimal detectable change (MDC) was calculated for Section 1 and 3 of the LLFI-10. Section 1 is focused on the activity limitations experienced by patients with a lower limb disorder whereas Section 3 involves patients indicating their current percentage of pre-injury duties. Section 1 of the LLFI-10 demonstrated excellent test-retest reliability (intra-class correlation coefficient (ICC) 0.98, 95 % CI 0.96-0.99) whilst Section 3 demonstrated high test-retest reliability (ICC 0.88, 95 % CI 0.79-0.94). MDC scores for Sections 1 and 3 were 1.27 points and 30.22 %, respectively. Internal consistency was demonstrated with a significant negative association (r s  = -0.83) between Sections 1 and 3 of the LLFI-10 (p < 0.001). This study demonstrates that Section 1 and 3 of the LLFI-10 are reliable for measuring functional ability in patients who have sustained lower limb burns in the previous 12 months, and furthermore, Section 1 is sensitive to changes in patient function over time.

Axial bone-socket displacement for persons with a traumatic transtibial amputation: The effect of elevated vacuum suspension at progressive body-weight loads.

PubMed

Darter, Benjamin J; Sinitski, Kirill; Wilken, Jason M

2016-10-01

Elevated vacuum suspension systems use a pump to draw air from the socket with the intent of reducing bone-socket motion as compared to passive suction systems. However, it remains unknown if elevated vacuum suspension systems decrease limb displacement uniformly during transitions from unloaded to full-body-weight support. To compare limb-socket motion between elevated vacuum and passive suction suspension sockets using a controlled loading paradigm. Comparative analysis. Persons with transtibial amputation were assessed while wearing either an elevated vacuum or passive suction suspension socket. Digital video fluoroscopy was used to measure axial bone-socket motion while the limb was loaded in 20% body-weight increments. An analysis of variance model was used to compare between suspension types. Total axial displacement (0%-100% body weight) was significantly lower using the elevated vacuum (vacuum: 1.3 cm, passive suction: 1.8 cm; p < 0.0001). Total displacement decreased primarily due to decreased motion during initial loading (0%-20%; p < 0.0001). Other body-weight intervals were not significantly different between systems. Elevated vacuum suspension reduced axial limb-socket motion by maintaining position of the limb within the socket during unloaded conditions. Elevated vacuum provided no meaningful improvement in limb-socket motion past initial loading. Excessive bone-socket motion contributes to poor residual limb health. Our results suggest elevated vacuum suspensions can reduce this axial displacement. Visual assessment of the images suggests that this occurs through the reduction or elimination of the air pocket between the liner and socket wall while the limb is unloaded. © The International Society for Prosthetics and Orthotics 2015.

The mechanics of landing when stepping down in unilateral lower-limb amputees.

PubMed

Jones, S F; Twigg, P C; Scally, A J; Buckley, J G

2006-02-01

The ability to successfully negotiate stairs and steps is an important factor for functional independence. While work has been undertaken to understand the biomechanics of gait in lower-limb amputees, little is known about how amputees negotiate stairs and steps. This study aimed to determine the mechanics of landing in unilateral lower-limb amputees when stepping down to a new level. A secondary aim was to assess the effects of using a shank-mounted shock-absorbing device (Tele-Torsion Pylon) on the mechanics of landing. Ten unilateral amputees (five transfemoral and five transtibial) and eight able-bodied controls performed single steps down to a new level (73 and 219 mm). Trials were repeated in amputees with the Tele-Torsion Pylon active and inactive. The mechanics of landing were evaluated by analysing peak limb longitudinal force, maximal limb shortening, lower extremity stiffness, and knee joint angular displacement during the initial contact period, and limb and ankle angle at the instant of ground-contact. Data were collected using a Vicon 3D motion analysis system and two force platforms. Amputees landed on a straightened and near vertical limb. This limb position was maintained in transfemoral amputees, whereas in transtibial amputees knee flexion occurred. As a result lower extremity stiffness was significantly greater in transfemoral amputees compared to transtibial amputees and able-bodied controls (P<0.001). The Tele-Torsion Pylon had little effect on the mechanics of landing in transtibial amputees, but brought about a reduction in lower extremity stiffness in transfemoral amputees (P<0.05). Amputees used a stepping strategy that ensured the direction of the ground reaction force vector was kept anterior of the knee joint centre. Using a Tele-Torsion Pylon may improve the mechanics of landing during downward stepping in transfemoral amputees.