Comparison of Multisegmental Foot and Ankle Motion Between Total Ankle Replacement and Ankle Arthrodesis in Adults.

PubMed

Seo, Sang Gyo; Kim, Eo Jin; Lee, Doo Jae; Bae, Kee Jeong; Lee, Kyoung Min; Lee, Dong Yeon

2017-09-01

Total ankle replacement (TAR) and ankle arthrodesis (AA) are usually performed for severe ankle arthritis. We compared postoperative foot segmental motion during gait in patients treated with TAR and AA. Gait analysis was performed in 17 and 7 patients undergoing TAR and AA, respectively. Subjects were evaluated using a 3-dimensional multisegmental foot model with 15 markers. Temporal gait parameters were calculated. The maximum and minimum values and the differences in hallux, forefoot, hindfoot, and arch in 3 planes (sagittal, coronal, transverse) were compared between the 2 groups. One hundred healthy adults were evaluated as a control. Gait speed was faster in the TAR ( P = .028). On analysis of foot and ankle segmental motion, the range of hindfoot sagittal motion was significantly greater in the TAR (15.1 vs 10.2 degrees in AA; P = .004). The main component of motion increase was hindfoot dorsiflexion (12.3 and 8.6 degrees). The range of forefoot sagittal motion was greater in the TAR (9.3 vs 5.8 degrees in AA; P = .004). Maximum ankle power in the TAR (1.16) was significantly higher than 0.32 in AA; P = .008). However, the range of hindfoot and forefoot sagittal motion was decreased in both TAR and AA compared with the control group ( P = .000). Although biomechanical results of TAR and AA were not similar to those in the normal controls, joint motions in the TAR more closely matched normal values. Treatment decision making should involve considerations of the effect of surgery on the adjacent joints. Level III, case-control study.

Sagittal and transversal plane deformity in thoracic scoliosis.

PubMed

Kotwicki, Tomasz

2002-01-01

The aim of the study was to assess the sagittal and transversal plane deformity of the spine in thoracic scoliosis by the mean of 3-D radiographic analysis. 46 patients admitted for surgery for thoracic idiopathic scoliosis underwent preoperative radiographic assessment. All patients presented the same pattern of the coronal plane deformity: single right thoracic curve (Lenke 1, King 3). Neither lumbar nor proximal thoracic structural curve were present. The Cobb angle varied from 41gamma to 77 gamma (mean 55,4 gamma +/- 8,6 gamma). Long cassette standing antero-posterior and lateral radiographs were analysed. Three-dimensional reconstruction with Rachis 91TM software was performed for each pair of radiographs. The following parameters were assessed: sagittal thoracic Cobb angle (Th4-Th12), upper thoracic kyphosis angle (Th5-Th8), lower thoracic kyphosis angle (Th9-Th12), superior and inferior hemi-curve sagittal angles, lumbar lordosis, sacral slope, sacral incidence, vertebral plate index, segmental vertebral axial rotation throughout the thoracic and lumbar spine. Results showed great variability of parameters assessed. The non-harmonious distribution of kyphosis was demonstrated in the thoracic spine. Local Th9-Th12 hypokyphosis and adjacent local Th5-Th8 hyperkyphosis constitute the most typical sagittal pathologies. So called normokyphotic curves were composed of one hyperkyphotic and one hypokyphotic zone. Th1-Th4 segment revealed two patterns of segmental rotation distribution: a purely compensatory curve with no vertebral axial rotation or a rotated curve presenting the morphology intermediate between Lenke 1 and Lenke 2 types (or King 3 and King 5). curves presenting the same coronal plane deformity differ in their morphology assessed in the two other planes; global thoracic kyphosis angle is a misleading parameter because it covers hypo- and hyperkyphotic zones; local distal thoracic (Th9-Th12) hypokyphosis is present in idiopathic thoracic scoliosis.

Contribution of calcaneal and leg segment rotations to ankle joint dorsiflexion in a weight-bearing task.

PubMed

Chizewski, Michael G; Chiu, Loren Z F

2012-05-01

Joint angle is the relative rotation between two segments where one is a reference and assumed to be non-moving. However, rotation of the reference segment will influence the system's spatial orientation and joint angle. The purpose of this investigation was to determine the contribution of leg and calcaneal rotations to ankle rotation in a weight-bearing task. Forty-eight individuals performed partial squats recorded using a 3D motion capture system. Markers on the calcaneus and leg were used to model leg and calcaneal segment, and ankle joint rotations. Multiple linear regression was used to determine the contribution of leg and calcaneal segment rotations to ankle joint dorsiflexion. Regression models for left (R(2)=0.97) and right (R(2)=0.97) ankle dorsiflexion were significant. Sagittal plane leg rotation had a positive influence (left: β=1.411; right: β=1.418) while sagittal plane calcaneal rotation had a negative influence (left: β=-0.573; right: β=-0.650) on ankle dorsiflexion. Sagittal plane rotations of the leg and calcaneus were positively correlated (left: r=0.84, P<0.001; right: r=0.80, P<0.001). During a partial squat, the calcaneus rotates forward. Simultaneous forward calcaneal rotation with ankle dorsiflexion reduces total ankle dorsiflexion angle. Rear foot posture is reoriented during a partial squat, allowing greater leg rotation in the sagittal plane. Segment rotations may provide greater insight into movement mechanics that cannot be explained via joint rotations alone. Copyright © 2012 Elsevier B.V. All rights reserved.

Improvement in gait following combined ankle and subtalar arthrodesis.

PubMed

Tenenbaum, Shay; Coleman, Scott C; Brodsky, James W

2014-11-19

This study assessed the hypothesis that arthrodesis of both the ankle and the hindfoot joints produces an objective improvement of function as measured by gait analysis of patients with severe ankle and hindfoot arthritis. Twenty-one patients with severe ankle and hindfoot arthritis who underwent unilateral tibiotalocalcaneal arthrodesis with an intramedullary nail were prospectively studied with three-dimensional (3D) gait analysis at a minimum of one year postoperatively. The mean age at the time of the operation was fifty-nine years, and the mean duration of follow-up was seventeen months (range, twelve to thirty-one months). Temporospatial measurements included cadence, step length, walking velocity, and total support time. The kinematic parameters were sagittal plane motion of the ankle, knee, and hip. The kinetic parameters were sagittal plane ankle power and moment and hip power. Symmetry of gait was analyzed by comparing the step lengths on the affected and unaffected sides. There was significant improvement in multiple parameters of postoperative gait as compared with the patients' own preoperative function. Temporospatial data showed significant increases in cadence (p = 0.03) and walking speed (p = 0.001) and decreased total support time (p = 0.02). Kinematic results showed that sagittal plane ankle motion had decreased, from 13.2° preoperatively to 10.2° postoperatively, in the operatively treated limb (p = 0.02), and increased from 22.2° to 24.1° (p = 0.01) in the contralateral limb. Hip motion on the affected side increased from 39° to 43° (p = 0.007), and knee motion increased from 56° to 60° (p = 0.054). Kinetic results showed significant increases in ankle moment (p < 0.0001) of the operatively treated limb, ankle power of the contralateral limb (p = 0.009), and hip power on the affected side (p = 0.005) postoperatively. There was a significant improvement in gait symmetry (p = 0.01). There was a small loss of sagittal plane motion in the

Improved ankle push-off power following cheilectomy for hallux rigidus: a prospective gait analysis study.

PubMed

Smith, Sheryl M; Coleman, Scott C; Bacon, Stacy A; Polo, Fabian E; Brodsky, James W

2012-06-01

There is limited objective scientific information on the functional effects of cheilectomy. The purpose of this study was to test the hypothesis that cheilectomy for hallux rigidus improves gait by increasing ankle push-off power. Seventeen patients with symptomatic Stage 1 or Stage 2 hallux rigidus were studied. Pre- and postoperative first metatarsophalangeal (MTP) range of motion and AOFAS hallux scores were recorded. A gait analysis was performed within 4 weeks prior to surgery and repeated at a minimum of 1 year after surgery. Gait analysis was done using a three-dimensional motion capture system and a force platform embedded in a 10-m walkway. Gait velocity sagittal plane ankle range of motion and peak sagittal plane ankle push-off power were analyzed. Following cheilectomy, significant increases were noted for first MTP range of motion and AOFAS hallux score. First MTP motion improved an average of 16.7 degrees, from means of 33.9 degrees preoperatively to 50.6 degrees postoperatively (p<0.001). AOFAS hallux score increased from 62 to 81 (p<0.007). As demonstrated through gait anaylsis, a significant increase in postoperative peak sagittal plane ankle push-off power from 1.71±0.92 W/kg to 2.05±0.75 W/kg (p<0.04). In addition to clinically increased range of motion and improved AOFAS Hallux score, first MTP joint cheilectomy produced objective improvement in gait, as measured by increased peak sagittal-plane ankle push-off power.

Dynamic balance deficits in individuals with chronic ankle instability compared to ankle sprain copers 1 year after a first-time lateral ankle sprain injury.

PubMed

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

2016-04-01

To quantify the dynamic balance deficits that characterise a group with chronic ankle instability compared to lateral ankle sprain copers and non-injured controls using kinematic and kinetic outcomes. Forty-two participants with chronic ankle instability and twenty-eight lateral ankle sprain copers were initially recruited within 2 weeks of sustaining a first-time, acute lateral ankle sprain and required to attend our laboratory 1 year later to complete the current study protocol. An additional group of non-injured individuals were also recruited to act as a control group. All participants completed the anterior, posterior-lateral and posterior-medial reach directions of the star excursion balance test. Sagittal plane kinematics of the lower extremity and associated fractal dimension of the centre of pressure path were also acquired. Participants with chronic ankle instability displayed poorer performance in the anterior, posterior-medial and posterior-lateral reach directions compared with controls bilaterally, and in the posterior-lateral direction compared with lateral ankle sprain copers on their 'involved' limb only. These performance deficits in the posterior-lateral and posterior-medial directions were associated with reduced flexion and dorsiflexion displacements at the hip, knee and ankle at the point of maximum reach, and coincided with reduced complexity of the centre of pressure path. In comparison with lateral ankle sprain copers and controls, participants with chronic ankle instability were characterised by dynamic balance deficits as measured using the SEBT. This was attested to reduced sagittal plane motions at the hip, knee and ankle joints, and reduced capacity of the stance limb to avail of its supporting base. III.

Pointing the foot without sickling: an examination of ankle movement during jumping.

PubMed

Jarvis, Danielle N; Kulig, Kornelia

2015-03-01

The sauté is a relatively simple dance jump that can be performed by both highly skilled dancers and non-dancers. However, there are characteristics of jumping unique to trained dancers, especially in terms of foot and ankle movement during flight. Dancers are trained not to "sickle, " or to avoid the anatomically coupled ankle inversion that occurs with plantar flexion, maintaining the appearance of a straight line through the lower leg and foot. The purpose of this study was to examine ankle movements in elite dancers compared to non-dancers. Twenty healthy females, 10 with no prior dance training and 10 professional dancers, performed 20 consecutive sautés while three-dimensional kinematic data were collected. Sagittal and frontal plane kinematics were calculated and vector coding methods were used to quantify coordination patterns within the ankle in the sagittal and frontal planes. This pattern was chosen for analysis to identify the avoidance of a sickled foot by trained dancers. Peak ankle positions and coordination patterns between groups were examined using independent t-tests (a <0.05). Dancers demonstrated greater peak plantar flexion (p<0.01) and less change in ankle angle during the flight phase (p= 0.01), signifying holding the pointed foot position during flight. There was no statistically significant difference in sagittal and frontal plane ankle coupling (p= 0.15); however, the Cohen's d effect size for the difference in coupling was medium-to-large (0.73). Dynamic analysis of the foot and ankle during jumping demonstrates how elite dancers achieve the aesthetic requirements of dance technique.

Gait Kinematics After Taping in Participants With Chronic Ankle Instability

PubMed Central

Chinn, Lisa; Dicharry, Jay; Hart, Joseph M.; Saliba, Susan; Wilder, Robert; Hertel, Jay

2014-01-01

Context: Chronic ankle instability is characterized by repetitive lateral ankle sprains. Prophylactic ankle taping is a common intervention used to reduce the risk of ankle sprains. However, little research has been conducted to evaluate the effect ankle taping has on gait kinematics. Objective: To investigate the effect of taping on ankle and knee kinematics during walking and jogging in participants with chronic ankle instability. Design: Controlled laboratory study. Setting: Motion analysis laboratory. Patients or Participants: A total of 15 individuals (8 men, 7 women; age = 26.9 ± 6.8 years, height = 171.7 ± 6.3 cm, mass = 73.5 ± 10.7 kg) with self-reported chronic ankle instability volunteered. They had an average of 5.3 ± 3.1 incidences of ankle sprain. Intervention(s): Participants walked and jogged in shoes on a treadmill while untaped and taped. The tape technique was a traditional preventive taping procedure. Conditions were randomized. Main Outcome Measure(s): Frontal-plane and sagittal-plane ankle and sagittal-plane knee kinematics were recorded throughout the entire gait cycle. Group means and 90% confidence intervals were calculated, plotted, and inspected for percentages of the gait cycle in which the confidence intervals did not overlap. Results: During walking, participants were less plantar flexed from 64% to 69% of the gait cycle (mean difference = 5.73° ± 0.54°) and less inverted from 51% to 61% (mean difference = 4.34° ± 0.65°) and 76% to 81% (mean difference = 5.55° ± 0.54°) of the gait cycle when taped. During jogging, participants were less dorsiflexed from 12% to 21% (mean difference = 4.91° ± 0.18°) and less inverted from 47% to 58% (mean difference = 6.52° ± 0.12°) of the gait cycle when taped. No sagittal-plane knee kinematic differences were found. Conclusions: In those with chronic ankle instability, taping resulted in a more neutral ankle position during walking and jogging in shoes on a treadmill. This change in

The effect of ankle distraction on arthroscopic evaluation of syndesmotic instability: A cadaveric study.

PubMed

Lubberts, Bart; Guss, Daniel; Vopat, Bryan G; Wolf, Jonathon C; Moon, Daniel K; DiGiovanni, Christopher W

2017-12-01

To assist with visualization, orthopaedic surgeons often apply ankle distraction during arthroscopic procedures. The study aimed to investigate whether ankle distraction suppresses fibular motion in cadaveric specimens with an unstable syndesmotic injury. Fourteen fresh-frozen above knee specimens underwent arthroscopic assessment with 1) intact ligaments, 2) after sectioning of the anterior inferior tibiofibular ligament, the interosseous ligament, and the posterior inferior tibiofibular ligament, and 3) after sectioning of the deep and superficial deltoid ligament. In all scenarios, the lateral hook test, anterior-posterior hook test, and posterior-anterior hook test were applied. Each test was performed with and without ankle distraction. Coronal plane anterior and posterior tibiofibular diastasis as well as sagittal plane tibiofibular translation due to the applied load were arthroscopically measured. Tibiofibular diastasis in the coronal plane, as measured at both the anterior and posterior third of the incisura, was found to be significantly less when ankle distraction was applied, as compared to arthroscopic evaluation in the absence of distraction. In contrast, measurement of sagittal plane tibiofibular translation was not affected by ankle distraction. Since arthroscopic findings of syndesmotic instability are subtle the differential values of the syndesmotic measurements taken on and off distraction are clinically relevant. To optimally assess syndesmotic instability one should evaluate the syndesmosis without distraction or focus on fibular motion in the sagittal plane when distraction is required. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sagittal Distal Tibial Articular Angle and the Relationship to Talar Subluxation in Total Ankle Arthroplasty.

PubMed

Veljkovic, Andrea; Norton, Adam; Salat, Peter; Abbas, Kaniza Zahra; Saltzman, Charles; Femino, John E; Phisitkul, Phinit; Amendola, Annunziato

2016-09-01

Longevity of total ankle replacement (TAR) depends heavily on anatomic alignment. The lateral talar station (LTS) classifies the sagittal position of the talus relative to the tibia. We hypothesized that correcting the sagittal distal tibial articular angle (sDTAA) during TAR would anatomically realign the tibiotalar joint and potentially reduce the risk of prosthesis subluxation. The LTS (millimeters) and sDTAA (degrees) were measured twice by 2 blinded observers using weight-bearing lateral ankle radiographs obtained before (n = 96) and after (n = 94) TAR, with excellent interobserver and intraobserver reliability (correlation coefficient >0.9). Preoperative LTS was as follows: anterior (60.4%), posterior (27.1%), and neutral (12.5%). A strong preoperative correlation was found between LTS and sDTAA (r = 0.81; P < .0001). In ankles that were initially anterior and became less anterior postoperatively (n = 41), LTS decreased from an average 8.1 mm to 6.5 mm and the LTS changed 1.1 mm per degree of sDTAA change. In ankles that were initially posterior (n = 25), LTS increased from an average of -5.1 mm to -2.8 mm and the LTS changed 0.6 mm per degree of sDTAA change. The correlation between LTS and sDTAA was reduced postoperatively (r = 0.62; P < .0001). Our results suggest that rather than following generic recommendations, the surgeon should customize the sagittal distal tibial cut to the individual patient based on the preoperative LTS in order to achieve neutral TAR alignment. Level III, retrospective comparative series. © The Author(s) 2016.

Automatic extraction of the mid-sagittal plane using an ICP variant

NASA Astrophysics Data System (ADS)

Fieten, Lorenz; Eschweiler, Jörg; de la Fuente, Matías; Gravius, Sascha; Radermacher, Klaus

2008-03-01

Precise knowledge of the mid-sagittal plane is important for the assessment and correction of several deformities. Furthermore, the mid-sagittal plane can be used for the definition of standardized coordinate systems such as pelvis or skull coordinate systems. A popular approach for mid-sagittal plane computation is based on the selection of anatomical landmarks located either directly on the plane or symmetrically to it. However, the manual selection of landmarks is a tedious, time-consuming and error-prone task, which requires great care. In order to overcome this drawback, previously it was suggested to use the iterative closest point (ICP) algorithm: After an initial mirroring of the data points on a default mirror plane, the mirrored data points should be registered iteratively to the model points using rigid transforms. Finally, a reflection transform approximating the cumulative transform could be extracted. In this work, we present an ICP variant for the iterative optimization of the reflection parameters. It is based on a closed-form solution to the least-squares problem of matching data points to model points using a reflection. In experiments on CT pelvis and skull datasets our method showed a better ability to match homologous areas.

Serial Testing of Postural Control After Acute Lateral Ankle Sprain

PubMed Central

Buckley, W. E.; Denegar, Craig R.

2001-01-01

Objective: To identify subjects' changes in postural control during single-leg stance in the 4 weeks after acute lateral ankle sprain. Design and Setting: We used a 2 × 2 × 3 (side-by-plane-by-session) within-subjects design with repeated measures on all 3 factors. All tests were performed in a university laboratory. Subjects: Seventeen young adults (9 men, 8 women; age, 21.8 ± 5.9 years; mass, 74.9 ± 10.5 kg; height, 176.9 ± 7.1 cm) who had sustained unilateral acute mild or moderate lateral ankle sprains. Measurements: Measures of center-of-pressure excursion length, root mean square velocity of center-of-pressure excursions (VEL), and range of center-of-pressure excursions (RANGE) were calculated separately in the frontal and sagittal planes during 5-second trials of static single-leg stance. Results: We noted significant side-by-plane-by-session interactions for magnitude of center-of-pressure excursions in a given trial (PSL) (P = .004), VEL (P = .011), and RANGE (P = .009). Both PSL and VEL in the frontal plane were greater in the injured limbs compared with the uninjured limbs on day 1 and during week 2 but not during week 4, whereas sagittal-plane differences existed during all 3 testing sessions. Injured-limb, frontal-plane RANGE scores were greater than uninjured values at day 1 but not during weeks 2 or 4. No significant differences in sagittal-plane RANGE scores were seen. Conclusions: Postural control was significantly impaired in the injured limbs at day 1 and during week 2 after lateral ankle sprain but not during week 4. Consistent improvement in postural control measures on both injured and uninjured limbs was seen throughout the 4 weeks after ankle sprain. PMID:12937477

Management of Osseous and Soft-Tissue Ankle Equinus During Total Ankle Replacement.

PubMed

Roukis, Thomas S; Simonson, Devin C

2015-10-01

Obtaining functional alignment of a total ankle replacement, including physiologic sagittal plane range of motion, is paramount for a successful outcome. This article reviews the literature on techniques available for correction of osseous and soft-tissue equinus at the time of index total ankle replacement. These techniques include anterior tibiotalar joint cheilectomy, posterior superficial muscle compartment lengthening, posterior ankle capsule release, and release of the posterior portions of the medial and lateral collateral ligament complexes. The rationale for these procedures and the operative sequence of events for these procedures are presented. Copyright © 2015 Elsevier Inc. All rights reserved.

Measurement of lumbar spine intervertebral motion in the sagittal plane using videofluoroscopy.

PubMed

Harvey, Steven; Hukins, David; Smith, Francis; Wardlaw, Douglas; Kader, Deiary

2016-08-10

Static radiographic techniques are unable to capture the wealth of kinematic information available from lumbar spine sagittal plane motion. Demonstration of a viable non-invasive technique for acquiring and quantifying intervertebral motion of the lumbar spine in the sagittal plane. Videofluoroscopic footage of sagittal plane lumbar spine flexion-extension in seven symptomatic volunteers (mean age = 48 yrs) and one asymptomatic volunteer (age = 54 yrs) was recorded. Vertebral bodies were digitised using customised software employing a novel vertebral digitisation scheme that was minimally affected by out-of-plane motion. Measurement errors in intervertebral rotation (± 1°) and intervertebral displacement (± 0.5 mm) compare favourably with the work of others. Some subjects presenting with an identical condition (disc prolapse) exhibited a similar column vertebral flexion-extension relative to S1 (L3: max. 5.9°, min. 5.6°), while in others (degenerative disc disease) there was paradoxically a significant variation in this measurement (L3: max. 28.1°, min. 0.7°). By means of a novel vertebral digitisation scheme and customised digitisation/analysis software, sagittal plane intervertebral motion data of the lumbar spine data has been successfully extracted from videofluoroscopic image sequences. Whilst the intervertebral motion signatures of subjects in this study differed significantly, the available sample size precluded the inference of any clinical trends.

Ankle Dorsiflexion Displacement During Landing is Associated With Initial Contact Kinematics but not Joint Displacement.

PubMed

Begalle, Rebecca L; Walsh, Meghan C; McGrath, Melanie L; Boling, Michelle C; Blackburn, J Troy; Padua, Darin A

2015-08-01

The ankle, knee, and hip joints work together in the sagittal plane to absorb landing forces. Reduced sagittal plane motion at the ankle may alter landing strategies at the knee and hip, potentially increasing injury risk; however, no studies have examined the kinematic relationships between the joints during jump landings. Healthy adults (N = 30; 15 male, 15 female) performed jump landings onto a force plate while three-dimensional kinematic data were collected. Joint displacement values were calculated during the loading phase as the difference between peak and initial contact angles. No relationship existed between ankle dorsiflexion displacement during landing and three-dimensional knee and hip displacements. However, less ankle dorsiflexion displacement was associated with landing at initial ground contact with larger hip flexion, hip internal rotation, knee flexion, knee varus, and smaller plantar flexion angles. Findings of the current study suggest that restrictions in ankle motion during landing may contribute to contacting the ground in a more flexed position but continuing through little additional motion to absorb the landing. Transverse plane hip and frontal plane knee positioning may also occur, which are known to increase the risk of lower extremity injury.

The angle of inclination of the native ACL in the coronal and sagittal planes.

PubMed

Reid, Jonathan C; Yonke, Bret; Tompkins, Marc

2017-04-01

The purpose of this cross-sectional study was to evaluate the angle of inclination of the native anterior cruciate ligament (ACL) in both the sagittal and coronal planes and to evaluate these findings based on sex, height, BMI, and skeletal maturity. Inclusion criteria for the study included patients undergoing routine magnetic resonance imaging (MRI) of the knee at a single outpatient orthopedic center who had an intact ACL on MRI. Measurements of the angle of inclination were made on MRIs in both the sagittal and coronal planes. Patients were compared based on sex, height, BMI, and skeletal maturity. One-hundred and eighty-eight patients were included (36 skeletally immature/152 skeletally mature; 98 male/90 female). The overall angle of inclination was 74.3° ± 4.8° in the coronal plane and 46.9° ± 4.9° in the sagittal plane. Skeletally immature patients (coronal: 71.8° ± 6.1°; sagittal: 44.7° ± 5.5°) were significantly different in both coronal and sagittal planes (P = 0.04 and 0.01, respectively) from skeletally mature patients (coronal: 75.3° ± 4.7°; sagittal: 47.4° ± 4.7°). There were no differences based on sex, height, or BMI. There are differences between the angle of inclination findings in this study and other studies, which could be due to MRI and measurement techniques. Clinically, skeletal maturity may be important to account for when using the ACL angle of inclination to evaluate anatomic ACL reconstruction. Prognostic retrospective study, Level of evidence III.

Lower extremity energy absorption and biomechanics during landing, part I: sagittal-plane energy absorption analyses.

PubMed

Norcross, Marc F; Lewek, Michael D; Padua, Darin A; Shultz, Sandra J; Weinhold, Paul S; Blackburn, J Troy

2013-01-01

Eccentric muscle actions of the lower extremity absorb kinetic energy during landing. Greater total sagittal-plane energy absorption (EA) during the initial impact phase (INI) of landing has been associated with landing biomechanics considered high risk for anterior cruciate ligament (ACL) injury. We do not know whether groups with different INI EA magnitudes exhibit meaningful differences in ACL-related landing biomechanics and whether INI EA might be useful to identify ACL injury-risk potential. To compare biomechanical factors associated with noncontact ACL injury among sagittal-plane INI EA groups and to determine whether an association exists between sex and sagittal-plane INI EA group assignment to evaluate the face validity of using sagittal-plane INI EA to identify ACL injury risk. Descriptive laboratory study. Research laboratory. A total of 82 (41 men, 41 women; age = 21.0 ± 2.4 years, height = 1.74 ± 0.10 m, mass = 70.3 ± 16.1 kg) healthy, physically active individuals volunteered. We assessed landing biomechanics using an electromagnetic motion-capture system and force plate during a double-legged jump-landing task. Total INI EA was used to group participants into high, moderate, and low tertiles. Sagittal- and frontal-plane knee kinematics; peak vertical and posterior ground reaction forces (GRFs); anterior tibial shear force; and internal hip extension, knee extension, and knee varus moments were identified and compared across groups using 1-way analyses of variance. We used a χ (2) analysis to compare male and female representation in the high and low groups. The high group exhibited greater knee-extension moment and posterior GRFs than both the moderate (P < .05) and low (P < .05) groups and greater anterior tibial shear force than the low group (P < .05). No other group differences were noted. Women were not represented more than men in the high group (χ(2) = 1.20, P = .27). Greater sagittal-plane INI EA likely indicates greater ACL loading

Center of mass trajectory and orientation to ankle and knee in sagittal plane is maintained with forward lean when backpack load changes during treadmill walking.

PubMed

Caron, Robert R; Wagenaar, Robert C; Lewis, Cara L; Saltzman, Elliot; Holt, Kenneth G

2013-01-04

Maintaining the normal shape and amplitude of the vertical trajectory of the center of mass (COM) during stance has been shown to maximize the efficiency of unloaded gait. Kinematic adaptations to load carriage, such as forward lean have yet to be understood in relation to COM movement. The purpose of this study is to better understand how load impacts the vertical COM(TSYS) trajectory and to clarify the impact of forward lean as it relates to the dynamics of sagittal plane COM(TSYS) movement during stance with changing load. 17 subjects walked on treadmill at a constant preferred walking velocity while nine different loads ranging from 12.5% to 40% bodyweight were systematically added and removed from a backpack. Kinematic data were collected using an Optotrak, three-dimensional motion analysis system and used to estimate position of the COM as well as segment and COM-to-joint vector orientation angles. The shape and amplitude of the COM vertical trajectory was maintained across all loaded conditions. The orientations of COM-to-ankle and -knee vectors were maintained in all loaded conditions except the heaviest load (40% BW). Results suggest that forward lean changed linearly with changes in load to maintain the COM-to-ankle and -knee vector orientations. COM vertical trajectory was maintained by a combination of invariants including lower-limb segment angles and a constant direction of toe-off impulse vector. The kinematic invariants found suggest a simplified control mechanism by which the system limits degrees of freedom and potentially minimizes torque about lower-extremity joints with added load. Copyright © 2012 Elsevier Ltd. All rights reserved.

Frontal plane hip and ankle sensorimotor function, not age, predicts unipedal stance time

PubMed Central

Allet, Lara; Kim, Hogene; Ashton-Miller, James; De Mott, Trina; Richardson, James K.

2011-01-01

Introduction Changes occur in muscles and nerves with aging. This study aimed to explore the relationship between unipedal stance time (UST) and frontal plane hip and ankle sensorimotor function in subjects with diabetic neuropathy. Methods UST, quantitative measures of frontal plane ankle proprioceptive thresholds, and ankle and hip motor function were tested in forty-one persons with a spectrum of lower limb sensorimotor function, ranging from healthy to moderately severe diabetic neuropathy. Results Frontal plane hip and ankle sensorimotor function demonstrated significant relationships with UST. Multivariate analysis identified only composite hip strength, composite ankle proprioceptive threshold, and age to be significant predictors of UST (R2=0.73); they explained 46%, 24% and 3% of the variance, respectively. Discussion/Conclusions Frontal plane hip strength was the single best predictor of UST and appeared to compensate for less precise ankle proprioceptive thresholds. This finding is clinically relevant given the possibility of strengthening the hip, even in patients with significant PN. . PMID:22431092

Frontal plane hip and ankle sensorimotor function, not age, predicts unipedal stance time.

PubMed

Allet, Lara; Kim, Hogene; Ashton-Miller, James; De Mott, Trina; Richardson, James K

2012-04-01

Changes occur in muscles and nerves with aging. In this study we explore the relationship between unipedal stance time (UST) and frontal plane hip and ankle sensorimotor function in subjects with diabetic neuropathy. UST, quantitative measures of frontal plane ankle proprioceptive thresholds, and ankle and hip motor function were tested in 41 subjects with a spectrum of lower limb sensorimotor function ranging from healthy to moderately severe diabetic neuropathy. Frontal plane hip and ankle sensorimotor function demonstrated significant relationships with UST. Multivariate analysis identified only composite hip strength, ankle proprioceptive threshold, and age to be significant predictors of UST (R(2) = 0.73), explaining 46%, 24%, and 3% of the variance, respectively. Frontal plane hip strength was the single best predictor of UST and appeared to compensate for less precise ankle proprioceptive thresholds. This finding is clinically relevant given the possibility of strengthening the hip, even in patients with significant peripheral neuropathy. Copyright © 2011 Wiley Periodicals, Inc.

Lower Extremity Energy Absorption and Biomechanics During Landing, Part I: Sagittal-Plane Energy Absorption Analyses

PubMed Central

Norcross, Marc F.; Lewek, Michael D.; Padua, Darin A.; Shultz, Sandra J.; Weinhold, Paul S.; Blackburn, J. Troy

2013-01-01

Context: Eccentric muscle actions of the lower extremity absorb kinetic energy during landing. Greater total sagittal-plane energy absorption (EA) during the initial impact phase (INI) of landing has been associated with landing biomechanics considered high risk for anterior cruciate ligament (ACL) injury. We do not know whether groups with different INI EA magnitudes exhibit meaningful differences in ACL-related landing biomechanics and whether INI EA might be useful to identify ACL injury-risk potential. Objective: To compare biomechanical factors associated with noncontact ACL injury among sagittal-plane INI EA groups and to determine whether an association exists between sex and sagittal-plane INI EA group assignment to evaluate the face validity of using sagittal-plane INI EA to identify ACL injury risk. Design: Descriptive laboratory study. Setting: Research laboratory. Patients or Other Participants: A total of 82 (41 men, 41 women; age = 21.0 ± 2.4 years, height = 1.74 ± 0.10 m, mass = 70.3 ± 16.1 kg) healthy, physically active individuals volunteered. Intervention(s): We assessed landing biomechanics using an electromagnetic motion-capture system and force plate during a double-legged jump-landing task. Main Outcome Measure(s): Total INI EA was used to group participants into high, moderate, and low tertiles. Sagittal- and frontal-plane knee kinematics; peak vertical and posterior ground reaction forces (GRFs); anterior tibial shear force; and internal hip extension, knee extension, and knee varus moments were identified and compared across groups using 1-way analyses of variance. We used a χ2 analysis to compare male and female representation in the high and low groups. Results: The high group exhibited greater knee-extension moment and posterior GRFs than both the moderate (P < .05) and low (P < .05) groups and greater anterior tibial shear force than the low group (P < .05). No other group differences were noted. Women were not represented more than

Kinematic predictors of star excursion balance test performance in individuals with chronic ankle instability.

PubMed

Hoch, Matthew C; Gaven, Stacey L; Weinhandl, Joshua T

2016-06-01

The Star Excursion Balance Test has identified dynamic postural control deficits in individuals with chronic ankle instability. While kinematic predictors of Star Excursion Balance Test performance have been evaluated in healthy individuals, this has not been thoroughly examined in individuals with chronic ankle instability. Fifteen individuals with chronic ankle instability completed the anterior reach direction of the Star Excursion Balance Test and weight-bearing dorsiflexion assessments. Maximum reach distances on the Star Excursion Balance Test were measured in cm and normalized to leg length. Three-dimensional trunk, hip, knee, and ankle motion of the stance limb were recorded during each anterior reach trial using a motion capture system. Sagittal, frontal, and transverse plane displacement observed from trial initiation to the point of maximum reach was calculated for each joint or segment and averaged for analysis. Pearson product-moment correlations were performed to examine the relationships between kinematic variables, maximal reach, and weight-bearing dorsiflexion. A backward multiple linear regression model was developed with maximal reach as the criterion variable and kinematic variables as predictors. Frontal plane displacement of the trunk, hip, and ankle and sagittal plane knee displacement were entered into the analysis. The final model (p=0.004) included all three frontal plane variables and explained 81% of the variance in maximal reach. Maximal reach distance and several kinematic variables were significantly related to weight-bearing dorsiflexion. Individuals with chronic ankle instability who demonstrated greater lateral trunk displacement toward the stance limb, hip adduction, and ankle eversion achieved greater maximal reach. Copyright © 2016. Published by Elsevier Ltd.

Frontal plane ankle proprioceptive thresholds and unipedal balance

PubMed Central

Son, Jaebum; Ashton-Miller, James A.; Richardson, James K.

2012-01-01

Reliable unipedal balance is fundamental to safe ambulation. Accordingly, older persons with peripheral neuropathy (PN), who are at increased risk for falls, demonstrate impaired unipedal balance. To explore the relationship between afferent function and unipedal balance, frontal plane proprioceptive thresholds at the ankle were quantified in 22 subjects (72.5 ± 6.3 years; 11 with PN and 11 matched controls) while they were standing using a foot cradle system and a staircase series of 100 rotational stimuli. PN subjects, as compared to controls, demonstrated shorter median unipedal balance times (3.4 ± 2.7 versus 14.3 ± 8.9 seconds; p = 0.0017) and greater (less precise) combined ankle inversion/eversion proprioceptive thresholds (1.17 ± 0.36 versus 0.65 ± 0.37 degrees; p = 0.0055). Combined ankle inversion/eversion proprioceptive thresholds explained approximately half the variance in unipedal balance time (R2 = 0.5138; p = 0.0004). Given prior work demonstrating a similarly strong relationship between ankle torque generation and unipedal balance, neuropathy-associated impairments in ankle frontal plane afferent and efferent function appear to be equally responsible for the inability of older persons with PN to reliably balance on one foot. They therefore provide distinct targets for intervention. PMID:19145650

Joint mobilization acutely improves landing kinematics in chronic ankle instability.

PubMed

Delahunt, Eamonn; Cusack, Kim; Wilson, Laura; Doherty, Cailbhe

2013-03-01

The objective of this study is to examine the acute effect of ankle joint mobilizations akin to those performed in everyday clinical practice on sagittal plane ankle joint kinematics during a single-leg drop landing in participants with chronic ankle instability (CAI). Fifteen participants with self-reported CAI (defined as <24 on the Cumberland Ankle Instability Tool) performed three single-leg drop landings under two different conditions: 1) premobilization and, 2) immediately, postmobilization. The mobilizations performed included Mulligan talocrural joint dorsiflexion mobilization with movement, Mulligan inferior tibiofibular joint mobilization, and Maitland anteroposterior talocrural joint mobilization. Three CODA cx1 units (Charnwood Dynamics Ltd., Leicestershire, UK) were used to provide information on ankle joint sagittal plane angular displacement. The dependent variable under investigation was the angle of ankle joint plantarflexion at the point of initial contact during the drop landing. There was a statistically significant acute decrease in the angle of ankle joint plantarflexion from premobilization (34.89° ± 4.18°) to postmobilization (31.90° ± 5.89°), t(14) = 2.62, P < 0.05 (two-tailed). The mean decrease in the angle of ankle joint plantarflexion as a result of the ankle joint mobilization was 2.98° with a 95% confidence interval ranging from 0.54 to 5.43. The eta squared statistic (0.32) indicated a large effect size. These results indicate that mobilization acted to acutely reduce the angle of ankle joint plantarflexion at initial contact during a single-leg drop landing. Mobilization applied to participants with CAI has a mechanical effect on the ankle joint, thus facilitating a more favorable positioning of the ankle joint when landing from a jump.

A Dynamic Finite Element Analysis of Human Foot Complex in the Sagittal Plane during Level Walking

PubMed Central

Qian, Zhihui; Ren, Lei; Ding, Yun; Hutchinson, John R.; Ren, Luquan

2013-01-01

The objective of this study is to develop a computational framework for investigating the dynamic behavior and the internal loading conditions of the human foot complex during locomotion. A subject-specific dynamic finite element model in the sagittal plane was constructed based on anatomical structures segmented from medical CT scan images. Three-dimensional gait measurements were conducted to support and validate the model. Ankle joint forces and moment derived from gait measurements were used to drive the model. Explicit finite element simulations were conducted, covering the entire stance phase from heel-strike impact to toe-off. The predicted ground reaction forces, center of pressure, foot bone motions and plantar surface pressure showed reasonably good agreement with the gait measurement data over most of the stance phase. The prediction discrepancies can be explained by the assumptions and limitations of the model. Our analysis showed that a dynamic FE simulation can improve the prediction accuracy in the peak plantar pressures at some parts of the foot complex by 10%–33% compared to a quasi-static FE simulation. However, to simplify the costly explicit FE simulation, the proposed model is confined only to the sagittal plane and has a simplified representation of foot structure. The dynamic finite element foot model proposed in this study would provide a useful tool for future extension to a fully muscle-driven dynamic three-dimensional model with detailed representation of all major anatomical structures, in order to investigate the structural dynamics of the human foot musculoskeletal system during normal or even pathological functioning. PMID:24244500

A dynamic finite element analysis of human foot complex in the sagittal plane during level walking.

PubMed

Qian, Zhihui; Ren, Lei; Ding, Yun; Hutchinson, John R; Ren, Luquan

2013-01-01

The objective of this study is to develop a computational framework for investigating the dynamic behavior and the internal loading conditions of the human foot complex during locomotion. A subject-specific dynamic finite element model in the sagittal plane was constructed based on anatomical structures segmented from medical CT scan images. Three-dimensional gait measurements were conducted to support and validate the model. Ankle joint forces and moment derived from gait measurements were used to drive the model. Explicit finite element simulations were conducted, covering the entire stance phase from heel-strike impact to toe-off. The predicted ground reaction forces, center of pressure, foot bone motions and plantar surface pressure showed reasonably good agreement with the gait measurement data over most of the stance phase. The prediction discrepancies can be explained by the assumptions and limitations of the model. Our analysis showed that a dynamic FE simulation can improve the prediction accuracy in the peak plantar pressures at some parts of the foot complex by 10%-33% compared to a quasi-static FE simulation. However, to simplify the costly explicit FE simulation, the proposed model is confined only to the sagittal plane and has a simplified representation of foot structure. The dynamic finite element foot model proposed in this study would provide a useful tool for future extension to a fully muscle-driven dynamic three-dimensional model with detailed representation of all major anatomical structures, in order to investigate the structural dynamics of the human foot musculoskeletal system during normal or even pathological functioning.

Effects of mid-foot contact area ratio on lower body kinetics/kinematics in sagittal plane during stair descent in women.

PubMed

Lee, Jinkyu; Hong, Yoon No Gregory; Shin, Choongsoo S

2016-07-01

The mid-foot contact area relative to the total foot contact area can facilitate foot arch structure evaluation. A stair descent motion consistently provides initial fore-foot contact and utilizes the foot arch more actively for energy absorption. The purpose of this study was to compare ankle and knee joint angle, moment, and work in sagittal plane during stair descending between low and high Mid-Foot-Contact-Area (MFCA) ratio group. The twenty-two female subjects were tested and classified into two groups (high MFCA and low MFCA) using their static MFCA ratios. The ground reaction force (GRF) and kinematics of ankle and knee joints were measured while stair descending. During the period between initial contact and the first peak in vertical GRF (early absorption phase), ankle negative work for the low MFCA ratio group was 33% higher than that for the high MFCA ratio group (p<0.05). However, ankle negative work was not significantly different between the two groups during the period between initial contact and peak dorsiflexion angle (early absorption phase+late absorption phase). The peak ankle dorsiflexion angle was smaller in the low MFCA ratio group (p<0.05). Our results suggest that strategy of energy absorption at the ankle and foot differs depending upon foot arch types classified by MFCA. The low MFCA ratio group seemed to absorb more impact energy using strain in the planar fascia during early absorption phase, whereas the high MFCA ratio group absorbed more impact energy using increased dorsiflexion during late absorption phase. Copyright © 2016 Elsevier B.V. All rights reserved.

Gender differences of sagittal knee and ankle biomechanics during stair-to-ground descent transition.

PubMed

Hong, Yoon No Gregory; Shin, Choongsoo S

2015-12-01

Falls on stairs often result in severe injury and occur twice as frequently in women. However, gender differences in kinetics and kinematics during stair descent are unknown. Thus, this study aimed to determine whether gender differences of knee and ankle biomechanics exist in the sagittal plane during the stair-to-ground descending transition. It was hypothesized that 1) women would reveal higher ground-toe-trochanter angle and lower ground-toe length during stair-to-ground descent transition than men; and 2) women would reveal lower peak knee extension moment during stair-to-ground descent transition than men. Fifteen men and fifteen women were recruited and performed a stair descent activity. Kinetic and kinematic data were obtained using a force plate and motion capture system. The women performed the stair descent with a lower peak knee extension moment and a peak knee power at the early weight acceptance phase. The women also revealed a higher ground-toe-trochanter angle and a lower ground-toe length, which indicated a more forward position of the lower extremity relative to the toe contact point at both the initial contact and at the time of peak kinematic and kinetic events. This study found that knee and ankle kinematics and kinetics differed significantly between the genders due to differences in ground-toe-trochanter angle. Women have a different stair descending strategy that reduces the demand of the lower extremity muscle function, but this strategy seems to increase the risk of falls. Copyright © 2015 Elsevier Ltd. All rights reserved.

Reviewing effectiveness of ankle assessment techniques for use in robot-assisted therapy.

PubMed

Zhang, Mingming; Davies, T Claire; Zhang, Yanxin; Xie, Shane

2014-01-01

This article provides a comprehensive review of studies that investigated ankle assessment techniques to better understand those that can be used in the real-time monitoring of rehabilitation progress for implementation in conjunction with robot-assisted therapy. Seventy-six publications published between January 1980 and August 2013 were selected based on eight databases. They were divided into two main categories (16 qualitative and 60 quantitative studies): 13 goniometer studies, 18 dynamometer studies, and 29 studies about innovative techniques. A total of 465 subjects participated in the 29 quantitative studies of innovative measurement techniques that may potentially be integrated in a real-time monitoring device, of which 19 studies included less than 10 participants. Results show that qualitative ankle assessment methods are not suitable for real-time monitoring in robot-assisted therapy, though they are reliable for certain patients, while the quantitative methods show great potential. The majority of quantitative techniques are reliable in measuring ankle kinematics and kinetics but are usually available only for use in the sagittal plane. Limited studies determine kinematics and kinetics in all three planes (sagittal, transverse, and frontal) where motions of the ankle joint and the subtalar joint actually occur.

Video raster stereography back shape reconstruction: a reliability study for sagittal, frontal, and transversal plane parameters.

PubMed

Schroeder, J; Reer, R; Braumann, K M

2015-02-01

As reliability of raster stereography was proved only for sagittal plane parameters with repeated measures on the same day, the present study was aiming at investigating variability and reliability of back shape reconstruction for all dimensions (sagittal, frontal, transversal) and for different intervals. For a sample of 20 healthy volunteers, intra-individual variability (SEM and CV%) and reliability (ICC ± 95% CI) were proved for sagittal (thoracic kyphosis, lumbar lordosis, pelvis tilt angle, and trunk inclination), frontal (pelvis torsion, pelvis and trunk imbalance, vertebral side deviation, and scoliosis angle), transversal (vertebral rotation), and functional (hyperextension) spine shape reconstruction parameters for different test-retest intervals (on the same day, between-day, between-week) by means of video raster stereography. Reliability was high for the sagittal plane (pelvis tilt, kyphosis and lordosis angle, and trunk inclination: ICC > 0.90), and good to high for lumbar mobility (0.86 < ICC < 0.97). Apart from sagittal plane spinal alignment, there was a lack of certainty for a high reproducibility indicated by wider ICC confidence intervals. So, reliability was fair to high for vertebral side deviation and the scoliosis angle (0.71 < ICC < 0.95), and poor to good for vertebral rotation values as well as for frontal plane upper body and pelvis position parameters (0.65 < ICC < 0.92). Coefficients for the between-day and between-week interval were a little lower than for repeated measures on the same day. Variability (SEM) was less than 1.5° or 1.5 mm, except for trunk inclination. Relative variability (CV) was greater in global trunk position and pelvis parameters (35-98%) than in scoliosis (14-20%) or sagittal sway parameters (4-8 %). Although we found a lower reproducibility for the frontal plane, raster stereography is considered to be a reliable method for the non-invasive, three-dimensional assessment of spinal alignment in normal non

Effect of Acute Alterations in Foot Strike Patterns during Running on Sagittal Plane Lower Limb Kinematics and Kinetics

PubMed Central

Valenzuela, Kevin A.; Lynn, Scott K.; Mikelson, Lisa R.; Noffal, Guillermo J.; Judelson, Daniel A.

2015-01-01

The purpose of this study was to determine the effect of foot strike patterns and converted foot strike patterns on lower limb kinematics and kinetics at the hip, knee, and ankle during a shod condition. Subjects were videotaped with a high speed camera while running a 5km at self-selected pace on a treadmill to determine natural foot strike pattern on day one. Preferred forefoot group (PFFG, n = 10) and preferred rear foot group (PRFG, n = 11) subjects were identified through slow motion video playback (n = 21, age = 22.8±2.2 years, mass = 73.1±14.5 kg, height 1.75 ± 0.10 m). On day two, subjects performed five overground run trials in both their natural and unnatural strike patterns while motion and force data were collected. Data were collected over two days so that foot strike videos could be analyzed for group placement purposes. Several 2 (Foot Strike Pattern –forefoot strike [FFS], rearfoot strike [RFS]) x 2 (Group – PFFG, PRFG) mixed model ANOVAs (p < 0.05) were run on speed, active peak vertical ground reaction force (VGRF), peak early stance and mid stance sagittal ankle moments, sagittal plane hip and knee moments, ankle dorsiflexion ROM, and sagittal plane hip and knee ROM. There were no significant interactions or between group differences for any of the measured variables. Within subject effects demonstrated that the RFS condition had significantly lower (VGRF) (RFS = 2.58 ± .21 BW, FFS = 2.71 ± 0.23 BW), dorsiflexion moment (RFS = -2.6 1± 0.61 Nm·kg-1, FFS = -3.09 ± 0.32 Nm·kg-1), and dorsiflexion range of motion (RFS = 17.63 ± 3.76°, FFS = 22.10 ± 5.08°). There was also a significantly higher peak plantarflexion moment (RFS = 0.23 ± 0.11 Nm·kg-1, FFS = 0.01 ± 0.01 Nm·kg-1), peak knee moment (RFS = 2.61 ± 0.54 Nm·kg-1, FFS = 2.39 ± 0.61 Nm·kg-1), knee ROM (RFS = 31.72 ± 2.79°, FFS = 29.58 ± 2.97°), and hip ROM (RFS = 42.72 ± 4.03°, FFS = 41.38 ± 3.32°) as compared with the FFS condition. This research suggests that

Effect of Acute Alterations in Foot Strike Patterns during Running on Sagittal Plane Lower Limb Kinematics and Kinetics.

PubMed

Valenzuela, Kevin A; Lynn, Scott K; Mikelson, Lisa R; Noffal, Guillermo J; Judelson, Daniel A

2015-03-01

The purpose of this study was to determine the effect of foot strike patterns and converted foot strike patterns on lower limb kinematics and kinetics at the hip, knee, and ankle during a shod condition. Subjects were videotaped with a high speed camera while running a 5km at self-selected pace on a treadmill to determine natural foot strike pattern on day one. Preferred forefoot group (PFFG, n = 10) and preferred rear foot group (PRFG, n = 11) subjects were identified through slow motion video playback (n = 21, age = 22.8±2.2 years, mass = 73.1±14.5 kg, height 1.75 ± 0.10 m). On day two, subjects performed five overground run trials in both their natural and unnatural strike patterns while motion and force data were collected. Data were collected over two days so that foot strike videos could be analyzed for group placement purposes. Several 2 (Foot Strike Pattern -forefoot strike [FFS], rearfoot strike [RFS]) x 2 (Group - PFFG, PRFG) mixed model ANOVAs (p < 0.05) were run on speed, active peak vertical ground reaction force (VGRF), peak early stance and mid stance sagittal ankle moments, sagittal plane hip and knee moments, ankle dorsiflexion ROM, and sagittal plane hip and knee ROM. There were no significant interactions or between group differences for any of the measured variables. Within subject effects demonstrated that the RFS condition had significantly lower (VGRF) (RFS = 2.58 ± .21 BW, FFS = 2.71 ± 0.23 BW), dorsiflexion moment (RFS = -2.6 1± 0.61 Nm·kg(-1), FFS = -3.09 ± 0.32 Nm·kg(-1)), and dorsiflexion range of motion (RFS = 17.63 ± 3.76°, FFS = 22.10 ± 5.08°). There was also a significantly higher peak plantarflexion moment (RFS = 0.23 ± 0.11 Nm·kg(-1), FFS = 0.01 ± 0.01 Nm·kg(-1)), peak knee moment (RFS = 2.61 ± 0.54 Nm·kg(-1), FFS = 2.39 ± 0.61 Nm·kg(-1)), knee ROM (RFS = 31.72 ± 2.79°, FFS = 29.58 ± 2.97°), and hip ROM (RFS = 42.72 ± 4.03°, FFS = 41.38 ± 3.32°) as compared with the FFS condition. This research suggests

Dynamic Postural-Stability Deficits After Cryotherapy to the Ankle Joint.

PubMed

Fullam, Karl; Caulfield, Brian; Coughlan, Garrett F; McGroarty, Mark; Delahunt, Eamonn

2015-09-01

Decreased postural stability is a primary risk factor for lower limb musculoskeletal injuries. During athletic competitions, cryotherapy may be applied during short breaks in play or during half-time; however, its effects on postural stability remain unclear. To investigate the acute effects of a 15-minute ankle-joint cryotherapy application on dynamic postural stability. Controlled laboratory study. University biomechanics laboratory. A total of 29 elite-level collegiate male field-sport athletes (age = 20.8 ± 1.12 years, height = 1.80 ± 0.06 m, mass = 81.89 ± 8.59 kg) participated. Participants were tested on the anterior (ANT), posterolateral (PL), and posteromedial (PM) reach directions of the Star Excursion Balance Test before and after a 15-minute ankle-joint cryotherapy application. Normalized reach distances; sagittal-plane kinematics of the hip, knee, and ankle joints; and associated mean velocity of the center-of-pressure path during performance of the ANT, PL, and PM reach directions of the Star Excursion Balance Test. We observed a decrease in reach-distance scores for the ANT, PL, and PM reach directions from precryotherapy to postcryotherapy (P < .05). No differences were observed in hip-, knee-, or ankle-joint sagittal-plane kinematics (P > .05). We noted a decrease in mean velocity of the center-of-pressure path from precryotherapy to postcryotherapy (P < .05) in all reach directions. Dynamic postural stability was adversely affected immediately after cryotherapy to the ankle joint.

Changes in active ankle dorsiflexion range of motion after acute inversion ankle sprain.

PubMed

Youdas, James W; McLean, Timothy J; Krause, David A; Hollman, John H

2009-08-01

Posterior calf stretching is believed to improve active ankle dorsiflexion range of motion (AADFROM) after acute ankle-inversion sprain. To describe AADFROM at baseline (postinjury) and at 2-wk time periods for 6 wk after acute inversion sprain. Randomized trial. Sports clinic. 11 men and 11 women (age range 11-54 y) with acute inversion sprain. Standardized home exercise program for acute inversion sprain. AADFROM with the knee extended. Time main effect on AADFROM was significant (F3,57 = 108, P < .001). At baseline, mean active sagittal-plane motion of the ankle was 6 degrees of plantar flexion, whereas at 2, 4, and 6 wk AADFROM was 7 degrees, 11 degrees, and 11 degrees, respectively. AADFROM increased significantly from baseline to week 2 and from week 2 to week 4. Normal AADFROM was restored within 4 wk after acute inversion sprain.

Inter-joint coordination strategies during unilateral stance 6-months following first-time lateral ankle sprain.

PubMed

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

2015-02-01

Longitudinal analyses of participants with a history of lateral ankle sprain are lacking. This investigation combined measures of inter-joint coordination and stabilometry to evaluate eyes-open (condition 1) and eyes-closed (condition 2) static unilateral stance performance in a group of participants, 6-months after they sustained an acute, first-time lateral ankle sprain in comparison to a control group. Sixty-nine participants with a 6-month history of first-time lateral ankle sprain and 20 non-injured controls completed three 20-second unilateral stance task trials in conditions 1 and 2. An adjusted coefficient of multiple determination statistic was used to compare stance limb 3-dimensional kinematic data for similarity in the aim of establishing patterns of lower-limb inter-joint coordination. The fractal dimension of the stance limb centre of pressure path was also calculated. Between-group analyses revealed significant differences in stance limb inter-joint coordination strategies for conditions 1 and 2, and in the fractal dimension of the centre-of-pressure path for condition 2 only. Injured participants displayed increases in ankle-hip linked coordination compared to controls in condition 1 (sagittal/frontal plane: 0.15 [0.14] vs 0.06 [0.04]; η(2)=.19; sagittal/transverse plane: 0.14 [0.11] vs 0.09 [0.05]; η(2)=0.14) and condition 2 (sagittal/frontal plane: 0.15 [0.12] vs 0.08 [0.06]; η(2)=0.23), with an associated decrease in the fractal dimension of the centre-of-pressure path (injured limb: 1.23 [0.13] vs 1.36 [0.13]; η(2)=0.20). Participants with a 6-month history of first-time lateral ankle sprain exhibit a hip-dominant coordination strategy for static unilateral stance compared to non-injured controls. Copyright © 2014 Elsevier Ltd. All rights reserved.

Metacarpal geometry changes during Thoroughbred race training are compatible with sagittal-plane cantilever bending.

PubMed

Merritt, J S; Davies, H M S

2010-11-01

Bending of the equine metacarpal bones during locomotion is poorly understood. Cantilever bending, in particular, may influence the loading of the metacarpal bones and surrounding structures in unique ways. We hypothesised that increased amounts of sagittal-plane cantilever bending may govern changes to the shape of the metacarpal bones of Thoroughbred racehorses during training. We hypothesised that this type of bending would require a linear change to occur in the combined second moment of area of the bones for sagittal-plane bending (I) during race training. Six Thoroughbred racehorses were used, who had all completed at least 4 years of race training at a commercial stable. The approximate change in I that had occurred during race training was computed from radiographic measurements at the start and end of training using a simple model of bone shape. A significant (P < 0.001), approximately linear pattern of change in I was observed in each horse, with the maximum change occurring proximally and the minimum change occurring distally. The pattern of change in I was compatible with the hypothesis that sagittal-plane cantilever bending governed changes to the shape of the metacarpal bones during race training. © 2010 EVJ Ltd.

Multi-segment foot kinematics after total ankle replacement and ankle arthrodesis during relatively long-distance gait.

PubMed

Rouhani, H; Favre, J; Aminian, K; Crevoisier, X

2012-07-01

This study aimed to investigate the influence of ankle osteoarthritis (AOA) treatments, i.e., ankle arthrodesis (AA) and total ankle replacement (TAR), on the kinematics of multi-segment foot and ankle complex during relatively long-distance gait. Forty-five subjects in four groups (AOA, AA, TAR, and control) were equipped with a wearable system consisting of inertial sensors installed on the tibia, calcaneus, and medial metatarsals. The subjects walked 50-m twice while the system measured the kinematic parameters of their multi-segment foot: the range of motion of joints between tibia, calcaneus, and medial metatarsals in three anatomical planes, and the peaks of angular velocity of these segments in the sagittal plane. These parameters were then compared among the four groups. It was observed that the range of motion and peak of angular velocities generally improved after TAR and were similar to the control subjects. However, unlike AOA and TAR, AA imposed impairments in the range of motion in the coronal plane for both the tibia-calcaneus and tibia-metatarsals joints. In general, the kinematic parameters showed significant correlation with established clinical scales (FFI and AOFAS), which shows their convergent validity. Based on the kinematic parameters of multi-segment foot during 50-m gait, this study showed significant improvements in foot mobility after TAR, but several significant impairments remained after AA. Copyright © 2012 Elsevier B.V. All rights reserved.

A comparison of economy and sagittal plane trunk movements among back-, back/front- and head-loading.

PubMed

Hudson, Sean; Cooke, Carlton; Davies, Simeon; West, Sacha; Gamieldien, Raeeq; Low, Chris; Lloyd, Ray

2018-05-14

It has been suggested that freedom of movement in the trunk could influence load carriage economy. This study aimed to compare the economy and sagittal plane trunk movements associated with three load carriage methods that constrain posture differently. Eighteen females walked at 3 km.h -1 with loads of 0, 3, 6, 9, 12, 15 and 20 kg carried on the back, back/front and head. Load carriage economy was assessed using the Extra Load Index (ELI). Change in sagittal plane trunk forward lean and trunk angle excursion from unloaded to loaded walking were assessed. Results show no difference in economy between methods (p = 0.483), despite differences in the change in trunk forward lean (p = 0.001) and trunk angle excursion (p = 0.021) from unloaded to loaded walking. We conclude that economy is not different among the three methods of load carriage, despite significant differences in sagittal plane trunk movements.

Acute influence of restricted ankle dorsiflexion angle on knee joint mechanics during gait.

PubMed

Ota, S; Ueda, M; Aimoto, K; Suzuki, Y; Sigward, S M

2014-06-01

Restrictions in range of ankle dorsiflexion (DF) motion can persist following ankle injuries. Ankle DF is necessary during terminal stance of gait, and its restricted range may affect knee joint kinematics and kinetics. The purpose of this study was to investigate the acute influence of varied levels of restricted ankle DF on knee joint sagittal and frontal plane kinematics and kinetics during gait. Thirty healthy volunteers walked with a custom-designed ankle brace that restricted ankle DF. Kinematics and kinetics were collected using a 7-camera motion analysis system and two force plates. Ankle dorsiflexion was restricted in 10-degree increments, allowing for four conditions: Free, light (LR), moderate (MR) and severe restriction (SR). Knee angles and moments were measured during terminal stance. Real peak ankle DF for Free, LR, MR, and SR were 13.7±4.8°, 11.6±5.0°, 7.5±5.3°, and 4.2±7.2°, respectively. Peak knee extension angles under the same conditions were -6.7±6.7°, -5.4±6.4°, -2.5±7.5°, and 0.6±7.8°, respectively, and the peak knee varus moment was 0.48±0.17 Nm/kg, 0.47±0.17 Nm/kg, 0.53±0.20 Nm/kg, and 0.57±0.20 Nm/kg. The knee varus moment was significantly increased from MR condition with an 8-degree restriction in ankle DF. Knee joint kinematics and kinetics in the sagittal and frontal planes were affected by reduced ankle DF during terminal stance of gait. Differences were observed with restriction in ankle DF range of approximately 8°. level III. Copyright © 2014 Elsevier B.V. All rights reserved.

The effect of tibiotalar alignment on coronal plane mechanics following total ankle replacement.

PubMed

Grier, A Jordan; Schmitt, Abigail C; Adams, Samuel B; Queen, Robin M

2016-07-01

Gait mechanics following total ankle replacement (TAR) have reported improved ankle motion following surgery. However, no studies have addressed the impact of preoperative radiographic tibiotalar alignment on post-TAR gait mechanics. We therefore investigated whether preoperative tibiotalar alignment (varus, valgus, or neutral) resulted in significantly different coronal plane mechanics or ground reaction forces post-TAR. We conducted a non-randomized study of 93 consecutive end-stage ankle arthritis patients. Standard weight-bearing radiographs were obtained preoperatively to categorize patients as having neutral (±4°), varus (≥5° of varus), or valgus (≥5° of valgus) coronal plane tibiotalar alignment. All patients underwent a standard walking assessment including three-dimensional lower extremity kinetics and kinematics preoperatively, 12 and 24 months postoperatively. A significant group by time interaction was observed for the propulsive vertical ground reaction force (vGRF), coronal plane hip range of motion (ROM) and the peak hip abduction moment. The valgus group demonstrated an increase in the peak knee adduction angle and knee adduction angle at heel strike when compared to the other groups. Coronal plane ankle ROM, knee and hip angles at heel strike, and the peak hip angle exhibited significant increases across time. Peak ankle inversion moment, peak knee abduction moment and the weight acceptance vGRF also exhibited significant increases across time. Neutral ankle alignment was achieved for all patients by 2 years following TAR. Restoration of neutral ankle alignment at the time of TAR in patients with preoperative varus or valgus tibiotalar alignment resulted in biomechanics similar to those of patients with neutral preoperative tibiotalar alignment by 24-month follow-up. Copyright © 2016 Elsevier B.V. All rights reserved.

Dynamic Postural-Stability Deficits After Cryotherapy to the Ankle Joint

PubMed Central

Fullam, Karl; Caulfield, Brian; Coughlan, Garrett F.; McGroarty, Mark; Delahunt, Eamonn

2015-01-01

Context  Decreased postural stability is a primary risk factor for lower limb musculoskeletal injuries. During athletic competitions, cryotherapy may be applied during short breaks in play or during half-time; however, its effects on postural stability remain unclear. Objective  To investigate the acute effects of a 15-minute ankle-joint cryotherapy application on dynamic postural stability. Design  Controlled laboratory study. Setting  University biomechanics laboratory. Patients or Other Participants  A total of 29 elite-level collegiate male field-sport athletes (age = 20.8 ± 1.12 years, height = 1.80 ± 0.06 m, mass = 81.89 ± 8.59 kg) participated. Intervention(s)  Participants were tested on the anterior (ANT), posterolateral (PL), and posteromedial (PM) reach directions of the Star Excursion Balance Test before and after a 15-minute ankle-joint cryotherapy application. Main Outcome Measure(s)  Normalized reach distances; sagittal-plane kinematics of the hip, knee, and ankle joints; and associated mean velocity of the center-of-pressure path during performance of the ANT, PL, and PM reach directions of the Star Excursion Balance Test. Results  We observed a decrease in reach-distance scores for the ANT, PL, and PM reach directions from precryotherapy to postcryotherapy (P < .05). No differences were observed in hip-, knee-, or ankle-joint sagittal-plane kinematics (P > .05). We noted a decrease in mean velocity of the center-of-pressure path from precryotherapy to postcryotherapy (P < .05) in all reach directions. Conclusions  Dynamic postural stability was adversely affected immediately after cryotherapy to the ankle joint. PMID:26285088

Usefulness of the dynamic gadolinium-enhanced magnetic resonance imaging with simultaneous acquisition of coronal and sagittal planes for detection of pituitary microadenomas.

PubMed

Lee, Han Bee; Kim, Sung Tae; Kim, Hyung-Jin; Kim, Keon Ha; Jeon, Pyoung; Byun, Hong Sik; Choi, Jin Wook

2012-03-01

Does dynamic gadolinium-enhanced imaging with simultaneous acquisition of coronal and sagittal planes improve diagnostic accuracy of pituitary microadenomas compared with coronal images alone? Fifty-six patients underwent 3-T sella MRI including dynamic simultaneous acquisition of coronal and sagittal planes after gadolinium injection. According to conspicuity, lesions were divided into four scores (0, no; 1, possible; 2, probable; 3, definite delayed enhancing lesion). Additional information on supplementary sagittal images compared with coronal ones was evaluated with a 4-point score (0, no; 1, possible; 2, probable; 3, definite additional information). Accuracy of tumour detection was calculated. Average scores for lesion detection of a combination of two planes, coronal, and sagittal images were 2.59, 2.32, and 2.18. 6/10 lesions negative on coronal images were detected on sagittal ones. Accuracy of a combination of two planes, of coronal and of sagittal images was 92.86%, 82.14% and 75%. Six patients had probable or definite additional information on supplementary sagittal images compared with coronal ones alone (10.71%). Dynamic MRI with combined coronal and sagittal planes was more accurate for detection of pituitary microadenomas than routinely used coronal images. Simultaneous dynamic enhanced acquisition can make study time fast and costs low. We present a new dynamic MRI technique for evaluating pituitary microadenomas • This technique provides simultaneous acquisition of contrast enhanced coronal and sagittal images. • This technique makes the diagnosis more accurate and reduces the examination time. • Such MR imaging only requires one single bolus of contrast agent.

Sagittal plane tilting deformity of the patellofemoral joint: a new concept in patients with chondromalacia patella.

PubMed

Aksahin, Ertugrul; Aktekin, Cem Nuri; Kocadal, Onur; Duran, Semra; Gunay, Cüneyd; Kaya, Defne; Hapa, Onur; Pepe, Murad

2017-10-01

The aims of this study were to evaluate sagittal plane alignment in patients with chondromalacia patella via magnetic resonance imaging (MRI), analyse the relationships between the location of the patellar cartilaginous lesions and sagittal alignment and finally investigate the relationships between the sagittal plane malalignment and patellofemoral loadings using by finite element analysis. Fifty-one patients who were diagnosed with isolated modified Outerbridge grade 3-4 patellar chondromalacia based on MRI evaluation and 51 control subjects were evaluated. Chondromalacia patella patients were divided into three subgroups according to the chondral lesion location as superior, middle and inferior. The patella-patellar tendon angle (P-PT) was used for evaluation of sagittal alignment of patellofemoral joint. Each subgroup was compared with control group by using P-PT angle. To investigate the biomechanical effects of sagittal plane malpositioning on patellofemoral joint, bone models were created at 30°, 60° and 90° knee flexion by using mean P-PT angles, which obtained from patients with chondromalacia patellae and control subjects. The total loading and contact area values of the patellofemoral joints were investigated by finite element analysis. The mean age of all participants was 52.9 ± 8.2 years. The mean P-PT angle was significantly lower in chondromalacia group (142.1° ± 3.6°) compared to control group (144.5° ± 5.3°) (p = 0.008). Chondral lesions were located in superior, middle and inferior zones in 16, 20 and 15 patients, respectively. The mean P-PT angles in patients with superior (141.8 ± 2.7) and inferior subgroups (139.2 ± 2.3) were significantly lower than the values in the control group (p < 0.05). The contact area values were detected higher in models with chondromalacia than in the control models at the same flexion degrees. There were increased loadings at 30° and 90° flexions in the sagittal patellar tilt models

Sagittal tibiotalar translation and clinical outcomes in mobile and fixed-bearing total ankle replacement.

PubMed

Usuelli, Federico G; Manzi, Luigi; Brusaferri, Giovanni; Neher, Robert E; Guelfi, Matteo; Maccario, Camilla

2017-06-01

Sagittal implant malalignment after total ankle replacement (TAR) has been considered to be a possible cause for premature implant failure. In a prior study, the change over time of the tibiotalar ratio (T-T ratio), which is the ratio between the posterior longitudinal talar length and the full longitudinal talar length, was assessed in 66 TARs where an unconstrained, mobile-bearing implant was implanted. The analysis documented an increase in the T-T ratio between 2 and 6 months post-surgery (on average from 34.6% to 37.2%). We hypothesized that this change might have been related to the presence of a mobile-bearing insert. In order to test our hypothesis, we designed a study to compare the translation of the talus in TARs performed with an unconstrained, mobile-bearing implant (designated the "Mobile ankle") and those performed with a semi-constrained, fixed-bearing implant (designated the "Fixed ankle"). The study included 71 consecutive patients (71 ankles) who underwent TAR with the Mobile ankle and 24 consecutive patients (24 ankles) who received the Fixed ankle from May 2011 to December 2014. Patients were assessed clinically and radiologically preoperatively (T 0 ), at 6 months (T 2 ) and 12 months (T 3 ) post-surgery. There was also a radiological assessment at 2 months post-surgery (T 1 ). The comparison of the T-T ratio between the two implant groups and over time indicated an interaction between time and group, therefore the changes of the T-T ratio over time were affected by the implant type factor (P<0.001). The changes of the postoperative T-T ratio over time were not significant in the Fixed ankle group (35.7±6.7% at T 1 , T 2 , and T 3 ; P=1.0 for each pairwise comparison). In the Mobile ankle group, the T-T ratio at 2 months (34.4±5.5%) was significantly different to the T-T ratio at 6 months (37.0±5.8%; P<0.001; i.e. there was a significant posterior translation of the talus). The AOFAS score increased from preop to 12 months post-surgery in

Alignment in the transverse plane, but not sagittal or coronal plane, affects the risk of recurrent patella dislocation.

PubMed

Takagi, Shigeru; Sato, Takashi; Watanabe, Satoshi; Tanifuji, Osamu; Mochizuki, Tomoharu; Omori, Go; Endo, Naoto

2017-11-17

Abnormalities of lower extremity alignment (LEA) in recurrent patella dislocation (RPD) have been studied mostly by two-dimensional (2D) procedures leaving three-dimensional (3D) factors unknown. This study aimed to three-dimensionally examine risk factors for RPD in lower extremity alignment under the weight-bearing conditions. The alignment of 21 limbs in 15 RPD subjects was compared to the alignment of 24 limbs of 12 healthy young control subjects by an our previously reported 2D-3D image-matching technique. The sagittal, coronal, and transverse alignment in full extension as well as the torsional position of the femur (anteversion) and tibia (tibial torsion) under weight-bearing standing conditions were assessed by our previously reported 3D technique. The correlations between lower extremity alignment and RPD were assessed using multiple logistic regression analysis. The difference of lower extremity alignment in RPD between under the weight-bearing conditions and under the non-weight-bearing conditions was assessed. In the sagittal and coronal planes, there was no relationship (statistically or by clinically important difference) between lower extremity alignment angle and RPD. However, in the transverse plane, increased external tibial rotation [odds ratio (OR) 1.819; 95% confidence interval (CI) 1.282-2.581], increased femoral anteversion (OR 1.183; 95% CI 1.029-1.360), and increased external tibial torsion (OR 0.880; 95% CI 0.782-0.991) were all correlated with RPD. The tibia was more rotated relative to femur at the knee joint in the RPD group under the weight-bearing conditions compared to under the non-weight-bearing conditions (p < 0.05). This study showed that during weight-bearing, alignment parameters in the transverse plane related to the risk of RPD, while in the sagittal and coronal plane alignment parameters did not correlate with RPD. The clinical importance of this study is that the 3D measurements more directly, precisely, and sensitively

The association of visually-assessed quality of movement during jump-landing with ankle dorsiflexion range-of-motion and hip abductor muscle strength among healthy female athletes.

PubMed

Rabin, Alon; Einstein, Ofira; Kozol, Zvi

2018-05-01

To explore the association between ankle dorsiflexion (DF) range of motion (ROM), and hip abductor muscle strength, to visually-assessed quality of movement during jump-landing. Cross-sectional. Gymnasium of participating teams. 37 female volleyball players. Quality of movement in the frontal-plane, sagittal-plane, and overall (both planes) was visually rated as "good/moderate" or "poor". Weight-bearing Ankle DF ROM and hip abductor muscle strength were compared between participants with differing quality of movement. Weight-bearing DF ROM on both sides was decreased among participants with "poor" sagittal-plane quality of movement (dominant side: 50.8° versus 43.6°, P = .02; non-dominant side: 54.6° versus 45.9°, P = .01), as well as among participants with an overall "poor" quality of movement (dominant side: 51.8° versus 44.0°, P < .01; non-dominant side: 56.5° versus 45.1°, P < .01). Weight-bearing ankle DF on the non-dominant side was decreased among participants with a "poor" frontal-plane quality of movement (53.9° versus 46.0°, P = .02). No differences in hip abductor muscle strength were noted between participants with differing quality of movement. Visual assessment of jump-landing can detect differences in quality of movement that are associated with ankle DF ROM. Clinicians observing a poor quality of movement may wish to assess ankle DF ROM. Copyright © 2018 Elsevier Ltd. All rights reserved.

Lower extremity energy absorption and biomechanics during landing, part II: frontal-plane energy analyses and interplanar relationships.

PubMed

Norcross, Marc F; Lewek, Michael D; Padua, Darin A; Shultz, Sandra J; Weinhold, Paul S; Blackburn, J Troy

2013-01-01

Greater sagittal-plane energy absorption (EA) during the initial impact phase (INI) of landing is consistent with sagittal-plane biomechanics that likely increase anterior cruciate ligament (ACL) loading, but it does not appear to influence frontal-plane biomechanics. We do not know whether frontal-plane INI EA is related to high-risk frontal-plane biomechanics. To compare biomechanics among INI EA groups, determine if women are represented more in the high group, and evaluate interplanar INI EA relationships. Descriptive laboratory study. Research laboratory. Participants included 82 (41 men, 41 women; age = 21.0 ± 2.4 years, height = 1.74 ± 0.10 m, mass = 70.3 ± 16.1 kg) healthy, physically active volunteers. We assessed landing biomechanics with an electromagnetic motion-capture system and force plate. We calculated frontal- and sagittal-plane total, hip, knee, and ankle INI EA. Total frontal-plane INI EA was used to create high, moderate, and low tertiles. Frontal-plane knee and hip kinematics, peak vertical and posterior ground reaction forces, and peak internal knee-varus moment (pKVM) were identified and compared across groups using 1-way analyses of variance. We used a χ (2) analysis to evaluate male and female allocation to INI EA groups. We used simple, bivariate Pearson product moment correlations to assess interplanar INI EA relationships. The high-INI EA group exhibited greater knee valgus at ground contact, hip adduction at pKVM, and peak hip adduction than the low-INI EA group (P < .05) and greater peak knee valgus, pKVM, and knee valgus at pKVM than the moderate- (P < .05) and low- (P < .05) INI EA groups. Women were more likely than men to be in the high-INI EA group (χ(2) = 4.909, P = .03). Sagittal-plane knee and frontal-plane hip INI EA (r = 0.301, P = .006) and sagittal-plane and frontal-plane ankle INI EA were associated (r = 0.224, P = .04). No other interplanar INI EA relationships were found (P > .05). Greater frontal-plane INI EA was

Lower Extremity Energy Absorption and Biomechanics During Landing, Part II: Frontal-Plane Energy Analyses and Interplanar Relationships

PubMed Central

Norcross, Marc F.; Lewek, Michael D.; Padua, Darin A.; Shultz, Sandra J.; Weinhold, Paul S.; Blackburn, J. Troy

2013-01-01

Context: Greater sagittal-plane energy absorption (EA) during the initial impact phase (INI) of landing is consistent with sagittal-plane biomechanics that likely increase anterior cruciate ligament (ACL) loading, but it does not appear to influence frontal-plane biomechanics. We do not know whether frontal-plane INI EA is related to high-risk frontal-plane biomechanics. Objective: To compare biomechanics among INI EA groups, determine if women are represented more in the high group, and evaluate interplanar INI EA relationships. Design: Descriptive laboratory study. Setting: Research laboratory. Patients or Other Participants: Participants included 82 (41 men, 41 women; age = 21.0 ± 2.4 years, height = 1.74 ± 0.10 m, mass = 70.3 ± 16.1 kg) healthy, physically active volunteers. Intervention(s): We assessed landing biomechanics with an electromagnetic motion-capture system and force plate. Main Outcome Measure(s): We calculated frontal- and sagittal-plane total, hip, knee, and ankle INI EA. Total frontal-plane INI EA was used to create high, moderate, and low tertiles. Frontal-plane knee and hip kinematics, peak vertical and posterior ground reaction forces, and peak internal knee-varus moment (pKVM) were identified and compared across groups using 1-way analyses of variance. We used a χ2 analysis to evaluate male and female allocation to INI EA groups. We used simple, bivariate Pearson product moment correlations to assess interplanar INI EA relationships. Results: The high–INI EA group exhibited greater knee valgus at ground contact, hip adduction at pKVM, and peak hip adduction than the low–INI EA group (P < .05) and greater peak knee valgus, pKVM, and knee valgus at pKVM than the moderate– (P < .05) and low– (P < .05) INI EA groups. Women were more likely than men to be in the high–INI EA group (χ2 = 4.909, P = .03). Sagittal-plane knee and frontal-plane hip INI EA (r = 0.301, P = .006) and sagittal-plane and frontal-plane ankle INI EA were

5D CNS+ Software for Automatically Imaging Axial, Sagittal, and Coronal Planes of Normal and Abnormal Second-Trimester Fetal Brains.

PubMed

Rizzo, Giuseppe; Capponi, Alessandra; Persico, Nicola; Ghi, Tullio; Nazzaro, Giovanni; Boito, Simona; Pietrolucci, Maria Elena; Arduini, Domenico

2016-10-01

The purpose of this study was to test new 5D CNS+ software (Samsung Medison Co, Ltd, Seoul, Korea), which is designed to image axial, sagittal, and coronal planes of the fetal brain from volumes obtained by 3-dimensional sonography. The study consisted of 2 different steps. First in a prospective study, 3-dimensional fetal brain volumes were acquired in 183 normal consecutive singleton pregnancies undergoing routine sonographic examinations at 18 to 24 weeks' gestation. The 5D CNS+ software was applied, and the percentage of adequate visualization of brain diagnostic planes was evaluated by 2 independent observers. In the second step, the software was also tested in 22 fetuses with cerebral anomalies. In 180 of 183 fetuses (98.4%), 5D CNS+ successfully reconstructed all of the diagnostic planes. Using the software on healthy fetuses, the observers acknowledged the presence of diagnostic images with visualization rates ranging from 97.7% to 99.4% for axial planes, 94.4% to 97.7% for sagittal planes, and 92.2% to 97.2% for coronal planes. The Cohen κ coefficient was analyzed to evaluate the agreement rates between the observers and resulted in values of 0.96 or greater for axial planes, 0.90 or greater for sagittal planes, and 0.89 or greater for coronal planes. All 22 fetuses with brain anomalies were identified among a series that also included healthy fetuses, and in 21 of the 22 cases, a correct diagnosis was made. 5D CNS+ was efficient in successfully imaging standard axial, sagittal, and coronal planes of the fetal brain. This approach may simplify the examination of the fetal central nervous system and reduce operator dependency.

Radiographic diagnosis of sagittal plane rotational displacement in pelvic fractures: a cadaveric model and clinical case study.

PubMed

Shui, Xiaolong; Ying, Xiaozhou; Kong, Jianzhong; Feng, Yongzeng; Hu, Wei; Guo, Xiaoshan; Wang, Gang

2015-08-01

Our objective was to measure the sagittal plane rotational (flexion and extension) displacement of hemipelvis radiologically and analyze the ratio of flexion and extension displacement of unstable pelvic fractures. We used 8 cadaveric models to study the radiographic evidence of pelvic fractures in the sagittal plane. We performed pelvic osteotomy on 8 cadavers to simulate anterior and posterior pelvic ring injury. Radiological data were measured in the flexion and extension group under different angles (5°, 10°, 15°, 20°, and 25°). We retrospectively reviewed 164 patients who were diagnosed with a unilateral fracture of the pelvis. Pelvic ring displacement was identified and recorded radiographically in cadaveric models. The flexion and extension displacement of pelvic fractures was measured in terms of the vertical distance of fracture from the top of iliac crest to the pubic tubercle (CD) or from the top of iliac crest to the lowest point of ischial tuberosity (AB). Fifty-seven pelves showed flexion displacement and 15 showed extension displacement. Closed reduction including internal fixation and external fixation was successfully used in 141 cases (86.0 %). The success rates of closed reduction in flexion and extension displacement groups were 77 and 73 %, respectively, which were lower than in unstable pelvic ring fractures. The sagittal plane rotation (flexion and extension) displacement of pelvic fractures could be measured by special points and lines on the radiographs. Minimally invasive reduction should be based on clearly identified differences between the sagittal plane rotation and the vertical displacement of pelvic fractures.

Inter-joint coordination strategies during unilateral stance following first-time, acute lateral ankle sprain: A brief report.

PubMed

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

2015-07-01

This investigation combined measures of inter-joint coordination and stabilometry to evaluate eyes-open (condition 1) and eyes-closed (condition 2) static unilateral stance performance in a group of participants with an acute, first-time lateral ankle sprain injury in comparison to a control group. Sixty-six participants with an acute first-time lateral ankle sprain and 19 non-injured controls completed three 20-second unilateral stance task trials in conditions 1 and 2. An adjusted coefficient of multiple determination statistic was used to compare stance limb 3-D kinematic data for similarity in the aim of establishing patterns of inter-joint coordination for these groups. Between-group analyses revealed significant differences in stance limb inter-joint coordination strategies for conditions 1 and 2. Injured participants displayed increases in ankle-hip linked coordination compared to controls in condition 1 (sagittal/frontal plane: 0.12 [0.09] vs 0.06 [0.04]; η(2)=.16) and condition 2 (sagittal/frontal plane: 0.18 [0.13] vs 0.08 [0.06]; η(2)=0.37). Participants with acute first-time lateral ankle sprain exhibit a hip-dominant coordination strategy for static unilateral stance compared to non-injured controls. Copyright © 2015 Elsevier Ltd. All rights reserved.

Kinematic and biomimetic assessment of a hydraulic ankle/foot in level ground and camber walking.

PubMed

Bai, Xuefei; Ewins, David; Crocombe, Andrew D; Xu, Wei

2017-01-01

Improved walking comfort has been linked with better bio-mimicking of the prosthetic ankle. This study investigated if a hydraulic ankle/foot can provide enough motion in both the sagittal and frontal planes during level and camber walking and if the hydraulic ankle/foot better mimics the biological ankle moment pattern compared with a fixed ankle/foot device. Five active male unilateral trans-femoral amputees performed level ground walking at normal and fast speeds and 2.5° camber walking in both directions using their own prostheses fitted with an "Echelon" hydraulic ankle/foot and an "Esprit" fixed ankle/foot. Ankle angles and the Trend Symmetry Index of the ankle moments were compared between prostheses and walking conditions. Significant differences between prostheses were found in the stance plantarflexion and dorsiflexion peaks with a greater range of motion being reached with the Echelon foot. The Echelon foot also showed significantly improved bio-mimicry of the ankle resistance moment in all walking conditions, either compared with the intact side of the same subject or with the "normal" mean curve from non-amputees. During camber walking, both types of ankle/foot devices showed similar changes in the frontal plane ankle angles. Results from a questionnaire showed the subjects were more satisfied with Echelon foot.

Altered Kinematics and Time to Stabilization During Drop-Jump Landings in Individuals With or Without Functional Ankle Instability

PubMed Central

Wright, Cynthia J.; Arnold, Brent L.; Ross, Scott E.

2016-01-01

Context It has been proposed that altered dynamic-control strategies during functional activity such as jump landings may partially explain recurrent instability in individuals with functional ankle instability (FAI). Objective To capture jump-landing time to stabilization (TTS) and ankle motion using a multisegment foot model among FAI, coper, and healthy control individuals. Design Cross-sectional study. Setting Laboratory. Patients or Other Participants Participants were 23 individuals with a history of at least 1 ankle sprain and at least 2 episodes of giving way in the past year (FAI), 23 individuals with a history of a single ankle sprain and no subsequent episodes of instability (copers), and 23 individuals with no history of ankle sprain or instability in their lifetime (controls). Participants were matched for age, height, and weight (age = 23.3 ± 3.8 years, height = 1.71 ± 0.09 m, weight = 69.0 ± 13.7 kg). Intervention(s) Ten single-legged drop jumps were recorded using a 12-camera Vicon MX motion-capture system and a strain-gauge force plate. Main Outcome Measures Mediolateral (ML) and anteroposterior (AP) TTS in seconds, as well as forefoot and hindfoot sagittal- and frontal-plane angles at jump-landing initial contact and at the point of maximum vertical ground reaction force were calculated. Results For the forefoot and hindfoot in the sagittal plane, group differences were present at initial contact (forefoot: P = .043, hindfoot: P = .004). At the hindfoot, individuals with FAI displayed more dorsiflexion than the control and coper groups. Time to stabilization differed among groups (AP TTS: P < .001; ML TTS: P = .040). Anteroposterior TTS was longer in the coper group than in the FAI or control groups, and ML TTS was longer in the FAI group than in the control group. Conclusions During jump landings, copers showed differences in sagittal-plane control, including less plantar flexion at initial contact and increased AP sway during stabilization

Knee joint passive stiffness and moment in sagittal and frontal planes markedly increase with compression.

PubMed

Marouane, H; Shirazi-Adl, A; Adouni, M

2015-01-01

Knee joints are subject to large compression forces in daily activities. Due to artefact moments and instability under large compression loads, biomechanical studies impose additional constraints to circumvent the compression position-dependency in response. To quantify the effect of compression on passive knee moment resistance and stiffness, two validated finite element models of the tibiofemoral (TF) joint, one refined with depth-dependent fibril-reinforced cartilage and the other less refined with homogeneous isotropic cartilage, are used. The unconstrained TF joint response in sagittal and frontal planes is investigated at different flexion angles (0°, 15°, 30° and 45°) up to 1800 N compression preloads. The compression is applied at a novel joint mechanical balance point (MBP) identified as a point at which the compression does not cause any coupled rotations in sagittal and frontal planes. The MBP of the unconstrained joint is located at the lateral plateau in small compressions and shifts medially towards the inter-compartmental area at larger compression forces. The compression force substantially increases the joint moment-bearing capacities and instantaneous angular rigidities in both frontal and sagittal planes. The varus-valgus laxities diminish with compression preloads despite concomitant substantial reductions in collateral ligament forces. While the angular rigidity would enhance the joint stability, the augmented passive moment resistance under compression preloads plays a role in supporting external moments and should as such be considered in the knee joint musculoskeletal models.

Kinematic and biomimetic assessment of a hydraulic ankle/foot in level ground and camber walking

PubMed Central

Bai, Xuefei; Ewins, David; Crocombe, Andrew D.

2017-01-01

Improved walking comfort has been linked with better bio-mimicking of the prosthetic ankle. This study investigated if a hydraulic ankle/foot can provide enough motion in both the sagittal and frontal planes during level and camber walking and if the hydraulic ankle/foot better mimics the biological ankle moment pattern compared with a fixed ankle/foot device. Five active male unilateral trans-femoral amputees performed level ground walking at normal and fast speeds and 2.5° camber walking in both directions using their own prostheses fitted with an “Echelon” hydraulic ankle/foot and an “Esprit” fixed ankle/foot. Ankle angles and the Trend Symmetry Index of the ankle moments were compared between prostheses and walking conditions. Significant differences between prostheses were found in the stance plantarflexion and dorsiflexion peaks with a greater range of motion being reached with the Echelon foot. The Echelon foot also showed significantly improved bio-mimicry of the ankle resistance moment in all walking conditions, either compared with the intact side of the same subject or with the “normal” mean curve from non-amputees. During camber walking, both types of ankle/foot devices showed similar changes in the frontal plane ankle angles. Results from a questionnaire showed the subjects were more satisfied with Echelon foot. PMID:28704428

Test apparatus for the measurement of the flexibility of ankle-foot orthoses in planes other than the loaded plane.

PubMed

Klasson, B; Convery, P; Raschke, S

1998-04-01

Previous publications have reported on the flexibility of ankle-foot orthoses (AFO) only in the same plane as the applied load. This paper reports on a test apparatus developed to detect the flexibility of an AFO in 5 degrees of freedom when subjected to a plantar/dorsiflexion moment, a medial/lateral moment or a torque. A moment applied to an AFO in one plane induces angulation and translation in all planes.

Clinical examination results in individuals with functional ankle instability and ankle-sprain copers.

PubMed

Wright, Cynthia J; Arnold, Brent L; Ross, Scott E; Ketchum, Jessica; Ericksen, Jeffrey; Pidcoe, Peter

2013-01-01

Why some individuals with ankle sprains develop functional ankle instability and others do not (ie, copers) is unknown. Current understanding of the clinical profile of copers is limited. To contrast individuals with functional ankle instability (FAI), copers, and uninjured individuals on both self-reported variables and clinical examination findings. Cross-sectional study. Sports medicine research laboratory. Participants consisted of 23 individuals with a history of 1 or more ankle sprains and at least 2 episodes of giving way in the past year (FAI: Cumberland Ankle Instability Tool [CAIT] score = 20.52 ± 2.94, episodes of giving way = 5.8 ± 8.4 per month), 23 individuals with a history of a single ankle sprain and no subsequent episodes of instability (copers: CAIT score = 27.74 ± 1.69), and 23 individuals with no history of ankle sprain and no instability (uninjured: CAIT score = 28.78 ± 1.78). Self-reported disability was recorded using the CAIT and Foot and Ankle Ability Measure for Activities of Daily Living and for Sports. On clinical examination, ligamentous laxity and tenderness, range of motion (ROM), and pain at end ROM were recorded. Questionnaire scores for the CAIT, Foot and Ankle Ability Measure for Activities of Daily Living and for Sports, ankle inversion and anterior drawer laxity scores, pain with palpation of the lateral ligaments, ankle ROM, and pain at end ROM. Individuals with FAI had greater self-reported disability for all measures (P < .05). On clinical examination, individuals with FAI were more likely to have greater talar tilt laxity, pain with inversion, and limited sagittal-plane ROM than copers (P < .05). Differences in both self-reported disability and clinical examination variables distinguished individuals with FAI from copers at least 1 year after injury. Whether the deficits could be detected immediately postinjury to prospectively identify potential copers is unknown.

Model-Based Estimation of Ankle Joint Stiffness

PubMed Central

Misgeld, Berno J. E.; Zhang, Tony; Lüken, Markus J.; Leonhardt, Steffen

2017-01-01

We address the estimation of biomechanical parameters with wearable measurement technologies. In particular, we focus on the estimation of sagittal plane ankle joint stiffness in dorsiflexion/plantar flexion. For this estimation, a novel nonlinear biomechanical model of the lower leg was formulated that is driven by electromyographic signals. The model incorporates a two-dimensional kinematic description in the sagittal plane for the calculation of muscle lever arms and torques. To reduce estimation errors due to model uncertainties, a filtering algorithm is necessary that employs segmental orientation sensor measurements. Because of the model’s inherent nonlinearities and nonsmooth dynamics, a square-root cubature Kalman filter was developed. The performance of the novel estimation approach was evaluated in silico and in an experimental procedure. The experimental study was conducted with body-worn sensors and a test-bench that was specifically designed to obtain reference angle and torque measurements for a single joint. Results show that the filter is able to reconstruct joint angle positions, velocities and torque, as well as, joint stiffness during experimental test bench movements. PMID:28353683

Walking on uneven terrain with a powered ankle prosthesis: A preliminary assessment.

PubMed

Shultz, Amanda H; Lawson, Brian E; Goldfarb, Michael

2015-01-01

A successful walking gait with a powered prosthesis depends heavily on proper timing of power delivery, or push-off. This paper describes a control approach which provides improved walking on uneven terrain relative to previous work intended for use on even (level) terrain. This approach is motivated by an initial healthy subject study which demonstrated less variation in sagittal plane shank angle than sagittal plane ankle angle when walking on uneven terrain relative to even terrain. The latter therefore replaces the former as the control signal used to initiate push-off in the powered prosthesis described herein. The authors demonstrate improvement in consistency for several gait characteristics, relative to healthy, as well as controller characteristics with the new control approach, including a 50% improvement in the consistency of the percentage of stride at which push-off is initiated.

Effect of ankle braces on lower extremity joint energetics in single-leg landings.

PubMed

Gardner, Jacob K; McCaw, Steven T; Laudner, Kevin G; Smith, Peter J; Stafford, Lindsay N

2012-06-01

Ankle sprains are one of the most common injuries in competitive and recreational athletics. Studies have shown that the use of prophylactic ankle braces effectively reduces the frequency of ankle sprains in athletes. However, although it is generally accepted that the ankle braces are effective at reducing frontal plane motion, some researchers report that the design of the brace may also reduce ankle sagittal plane motion. The purpose of this study was to quantify lower extremity joint contributions to energy absorption during single-legged drop landings in three ankle brace conditions (no brace, boot brace, and hinged brace). Eleven physically active females experienced in landing and free of lower extremity injury (age = 22.3 ± 1.7 yr, height = 1.66 ± 0.04 m, mass = 58.43 ± 5.83 kg) performed 10 single-leg drop landings in three conditions (one unbraced, two braced) from a 0.33-m height. Measurements taken were hip, knee, and ankle joint impulse; hip, knee, ankle, and total work; and hip, knee, and ankle joint relative work. Total energy absorption remained consistent across the braced conditions (P = 0.057). Wearing the boot brace reduced relative ankle work (P = 0.04, Cohen d = 0.43) but did not change relative knee (P = 0.08, Cohen d = 0.32) or hip (P = 0.14, Cohen d = 0.20) work compared with the no-brace condition. In an ankle-braced condition, ankle, knee, and hip energetics may be altered depending on the design of the brace.

An algorithm based on OmniView technology to reconstruct sagittal and coronal planes of the fetal brain from volume datasets acquired by three-dimensional ultrasound.

PubMed

Rizzo, G; Capponi, A; Pietrolucci, M E; Capece, A; Aiello, E; Mammarella, S; Arduini, D

2011-08-01

To describe a novel algorithm, based on the new display technology 'OmniView', developed to visualize diagnostic sagittal and coronal planes of the fetal brain from volumes obtained by three-dimensional (3D) ultrasonography. We developed an algorithm to image standard neurosonographic planes by drawing dissecting lines through the axial transventricular view of 3D volume datasets acquired transabdominally. The algorithm was tested on 106 normal fetuses at 18-24 weeks of gestation and the visualization rates of brain diagnostic planes were evaluated by two independent reviewers. The algorithm was also applied to nine cases with proven brain defects. The two reviewers, using the algorithm on normal fetuses, found satisfactory images with visualization rates ranging between 71.7% and 96.2% for sagittal planes and between 76.4% and 90.6% for coronal planes. The agreement rate between the two reviewers, as expressed by Cohen's kappa coefficient, was > 0.93 for sagittal planes and > 0.89 for coronal planes. All nine abnormal volumes were identified by a single observer from among a series including normal brains, and eight of these nine cases were diagnosed correctly. This novel algorithm can be used to visualize standard sagittal and coronal planes in the fetal brain. This approach may simplify the examination of the fetal brain and reduce dependency of success on operator skill. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.

Simulation of a slope adapting ankle prosthesis provided by semi-active damping.

PubMed

LaPrè, Andrew K; Sup, Frank

2011-01-01

Modern passive prosthetic foot/ankles cannot adapt to variations in ground slope. The lack of active adaptation significantly compromises an amputee's balance and stability on uneven terrains. To address this deficit, this paper proposes an ankle prosthesis that uses semi-active damping as a mechanism to provide active slope adaptation. The conceptual ankle prosthesis consists of a modulated damper in series with a spring foot that allows the foot to conform to the angle of the surface in the sagittal plane. In support of this approach, biomechanics data is presented showing unilateral transtibial amputees stepping on a wedge with their daily-use passive prosthesis. Based on this data, a simulation of the ankle prosthesis with semi-active damping is developed. The model shows the kinematic adaptation of the prosthesis to sudden changes in ground slope. The results show the potential of an ankle prosthesis with semi-active damping to actively adapt to the ground slope at each step.

Ankle muscle coactivation and its relationship with ankle joint kinematics and kinetics during gait in hemiplegic patients after stroke.

PubMed

Kitatani, Ryosuke; Ohata, Koji; Sato, Shuhei; Watanabe, Aki; Hashiguchi, Yu; Yamakami, Natsuki; Sakuma, Kaoru; Yamada, Shigehito

2016-06-01

Increased ankle muscle coactivation during gait is a compensation strategy for enhancing postural stability in patients after stroke. However, no previous studies have demonstrated that increased ankle muscle coactivation influenced ankle joint movements during gait in patients after stroke. To investigate the relationship between ankle muscle coactivation and ankle joint movements in hemiplegic patients after stroke. Seventeen patients after stroke participated. The coactivation index (CoI) at the ankle joint was calculated separately for the first and second double support (DS1 and DS2, respectively) and single support (SS) phases on the paretic and non-paretic sides during gait using surface electromyography. Simultaneously, three-dimensional motion analysis was performed to measure the peak values of the ankle joint angle, moment, and power in the sagittal plane. Ground reaction forces (GRFs) of the anterior and posterior components and centers of pressure (COPs) trajectory ranges and velocities were also measured. The CoI during the SS phase on the paretic side was negatively related to ankle dorsiflexion angle, ankle plantarflexion moment, ankle joint power generation, and COP velocity on the paretic side. Furthermore, the CoI during the DS2 phase on both sides was negatively related to anterior GRF amplitude on each side. Increased ankle muscle coactivation is related to decreased ankle joint movement during the SS phase on the paretic side to enhance joint stiffness and compensate for stance limb instability, which may be useful for patients who have paretic instability during the stance phase after stroke.

Complete duplication of bladder and urethra in a sagittal plane in a male infant: case report and literature review.

PubMed

Coker, Alisa M; Allshouse, Michael J; Koyle, Martin A

2008-08-01

Complete duplication of the bladder and urethra is a rare entity. It may occur in the coronal and sagittal planes, and is often associated with other organ system anomalies, in particular of the gastrointestinal tract. We report an unusual variant of sagittal duplication of the bladder, in a male, associated with rudimentary hindgut duplication, and review the literature pertaining to this unusual anomaly.

Time-varying impedance of the human ankle in the sagittal and frontal planes during straight walk and turning steps.

PubMed

Ficanha, Evandro M; Ribeiro, Guilherme A; Knop, Lauren; Rastgaar, Mo

2017-07-01

This paper describes the methods and experiment protocols for estimation of the human ankle impedance during turning and straight line walking. The ankle impedance of two human subjects during the stance phase of walking in both dorsiflexion plantarflexion (DP) and inversion eversion (IE) were estimated. The impedance was estimated about 8 axes of rotations of the human ankle combining different amounts of DP and IE rotations, and differentiating among positive and negative rotations at 5 instants of the stance length (SL). Specifically, the impedance was estimated at 10%, 30%, 50%, 70% and 90% of the SL. The ankle impedance showed great variability across time, and across the axes of rotation, with consistent larger stiffness and damping in DP than IE. When comparing straight walking and turning, the main differences were in damping at 50%, 70%, and 90% of the SL with an increase in damping at all axes of rotation during turning.

Weight-Bearing Dorsiflexion Range of Motion and Landing Biomechanics in Individuals With Chronic Ankle Instability

PubMed Central

Hoch, Matthew C.; Farwell, Kelley E.; Gaven, Stacey L.; Weinhandl, Joshua T.

2015-01-01

Context People with chronic ankle instability (CAI) exhibit less weight-bearing dorsiflexion range of motion (ROM) and less knee flexion during landing than people with stable ankles. Examining the relationship between dorsiflexion ROM and landing biomechanics may identify a modifiable factor associated with altered kinematics and kinetics during landing tasks. Objective To examine the relationship between weight-bearing dorsiflexion ROM and single-legged landing biomechanics in persons with CAI. Design Cross-sectional study. Setting Laboratory. Patients or Other Participants Fifteen physically active persons with CAI (5 men, 10 women; age = 21.9 ± 2.1 years, height = 168.7 ± 9.0 cm, mass = 69.4 ± 13.3 kg) participated. Intervention(s) Participants performed dorsiflexion ROM and single-legged landings from a 40-cm height. Sagittal-plane kinematics of the lower extremity and ground reaction forces (GRFs) were captured during landing. Main Outcome Measure(s) Static dorsiflexion was measured using the weight-bearing–lunge test. Kinematics of the ankle, knee, and hip were observed at initial contact, maximum angle, and sagittal displacement. Sagittal displacements of the ankle, knee, and hip were summed to examine overall sagittal displacement. Kinetic variables were maximum posterior and vertical GRFs normalized to body weight. We used Pearson product moment correlations to evaluate the relationships between dorsiflexion ROM and landing biomechanics. Correlations (r) were interpreted as weak (0.00–0.40), moderate (0.41–0.69), or strong (0.70–1.00). The coefficient of determination (r2) was used to determine the amount of explained variance among variables. Results Static dorsiflexion ROM was moderately correlated with maximum dorsiflexion (r = 0.49, r2 = 0.24), ankle displacement (r = 0.47, r2 = 0.22), and total displacement (r = 0.67, r2 = 0.45) during landing. Dorsiflexion ROM measured statically and during landing demonstrated moderate to strong

The effect of age and speed on foot and ankle kinematics assessed using a 4-segment foot model.

PubMed

van Hoeve, Sander; Leenstra, Bernard; Willems, Paul; Poeze, Martijn; Meijer, Kenneth

2017-09-01

The effects of age and speed on foot and ankle kinematics in gait studies using foot models are not fully understood, whereas this can have significant influence. We analyzed these variables with the 4-segment Oxford foot model. Twenty-one healthy subjects (aged 20-65 years) were recruited for gait analysis. The effect of speed on foot and ankle kinematics was assessed by comparing results during slow walking and fast walking. To assess the effect of age, a group of 13 healthy young adults (aged 20-24 years) were compared with a group of 8 older adults (aged 53-65 years). Also, the interaction between age and speed was analyzed. Regarding speed, there was a significant difference between forefoot/hindfoot motion in the sagittal plane (flexion/extension) during both loading- and push-off phase (P = .004, P < .001). Between hindfoot/tibia, there was a significant difference for all parameters except for motion in the sagittal plane (flexion/extension) during push-off phase (P = .5). Age did not significantly influence kinematics. There was no interaction between age and speed. Our analysis found that speed significantly influenced the kinematic outcome parameters. This was more pronounced in the ankle joint. In contrast, no significant differences were found between younger and older healthy subjects.

Effects of changing speed on knee and ankle joint load during walking and running.

PubMed

de David, Ana Cristina; Carpes, Felipe Pivetta; Stefanyshyn, Darren

2015-01-01

Joint moments can be used as an indicator of joint loading and have potential application for sports performance and injury prevention. The effects of changing walking and running speeds on joint moments for the different planes of motion still are debatable. Here, we compared knee and ankle moments during walking and running at different speeds. Data were collected from 11 recreational male runners to determine knee and ankle joint moments during different conditions. Conditions include walking at a comfortable speed (self-selected pacing), fast walking (fastest speed possible), slow running (speed corresponding to 30% slower than running) and running (at 4 m · s(-1) ± 10%). A different joint moment pattern was observed between walking and running. We observed a general increase in joint load for sagittal and frontal planes as speed increased, while the effects of speed were not clear in the transverse plane moments. Although differences tend to be more pronounced when gait changed from walking to running, the peak moments, in general, increased when speed increased from comfortable walking to fast walking and from slow running to running mainly in the sagittal and frontal planes. Knee flexion moment was higher in walking than in running due to larger knee extension. Results suggest caution when recommending walking over running in an attempt to reduce knee joint loading. The different effects of speed increments during walking and running should be considered with regard to the prevention of injuries and for rehabilitation purposes.

Ambulant adults with spastic cerebral palsy: the validity of lower limb joint angle measurements from sagittal video recordings.

PubMed

Larsen, Kerstin L; Maanum, Grethe; Frøslie, Kathrine F; Jahnsen, Reidun

2012-02-01

In the development of a clinical program for ambulant adults with cerebral palsy (CP), we investigated the validity of joint angles measured from sagittal video recordings and explored if movements in the transversal plane identified with three-dimensional gait analysis (3DGA) affected the validity of sagittal video joint angle measurements. Ten observers, and 10 persons with spastic CP (19-63 years), Gross Motor Function Classification System I-II, participated in the study. Concurrent criterion validity between video joint angle measurements and 3DGA was assessed by Bland-Altman plots with mean differences and 95% limits of agreement (LoA). Pearson's correlation coefficients (r) and scatter plots were used supplementary. Transversal kinematics ≥2 SD from our reference band were defined as increased movement in the transversal plane. The overall mean differences in degrees between joint angles measured by 3DGA and video recordings (3°, 5° and -7° for the hip, knee and ankle respectively) and corresponding LoA (18°, 10° and 15° for the hip, knee and ankle, respectively) demonstrated substantial discrepancies between the two methods. The correlations ranged from low (r=0.39) to moderate (r=0.68). Discrepancy between the two measurements was seen both among persons with and without the presence of deviating transversal kinematics. Quantifying lower limb joint angles from sagittal video recordings in ambulant adults with spastic CP demonstrated low validity, and should be conducted with caution. This gives implications for selecting evaluation method of gait. Copyright © 2011 Elsevier B.V. All rights reserved.

Graft extrusion in both the coronal and sagittal planes is greater after medial compared with lateral meniscus allograft transplantation but is unrelated to early clinical outcomes.

PubMed

Lee, Dae-Hee; Lee, Chang-Rack; Jeon, Jin-Ho; Kim, Kyung-Ah; Bin, Seong-Il

2015-01-01

Graft extrusion after meniscus allograft transplantation (MAT) may be affected by horn fixation, which differs between medial and lateral MAT. Few studies have compared graft extrusion, especially sagittal extrusion, after medial and lateral MAT. In patients undergoing medial and lateral MAT, graft extrusion is likely similar and not correlated with postoperative Lysholm scores. Cohort study; Level of evidence, 2. Meniscus graft extrusion in the coronal and sagittal planes was compared in 51 knees undergoing medial MAT and 84 undergoing lateral MAT. Distances from the anterior and posterior articular cartilage margins to the anterior (anterior cartilage meniscus distance [ACMD]) and posterior (posterior cartilage meniscus distance [PCMD]) horns, respectively, were assessed on immediate postoperative magnetic resonance imaging and compared in patients undergoing medial and lateral MAT. Correlations between coronal and sagittal graft extrusion and between extrusion and the Lysholm score were compared in the 2 groups. In the coronal plane, mean absolute (4.3 vs 2.7 mm, respectively; P<.001) and relative (39% vs 21%, respectively; P<.001) graft extrusions were significantly greater for medial than lateral MAT. In the sagittal plane, mean absolute and relative ACMD and PCMD values were significantly greater for medial than lateral MAT (P<.001 each). For both medial and lateral MAT, mean absolute and relative ACMDs were significantly larger than PCMDs (P<.001 each). Graft extrusion>3 mm in the coronal plane was significantly more frequent in the medial (78%) than in the lateral (35%) MAT group. In the sagittal plane, the frequencies of ACMDs (72% vs 39%, respectively) and PCMDs (23% vs 4%, respectively) >3 mm were also significantly greater in the medial than in the lateral MAT group. Coronal and sagittal extrusions were not correlated with postoperative Lysholm scores for both medial and lateral MAT. The amount and incidence of graft extrusion were greater after medial

Sagittal plane gait characteristics in hip osteoarthritis patients with mild to moderate symptoms compared to healthy controls: a cross-sectional study.

PubMed

Eitzen, Ingrid; Fernandes, Linda; Nordsletten, Lars; Risberg, May Arna

2012-12-20

Existent biomechanical studies on hip osteoarthritic gait have primarily focused on the end stage of disease. Consequently, there is no clear consensus on which specific gait parameters are of most relevance for hip osteoarthritis patients with mild to moderate symptoms. The purpose of this study was to explore sagittal plane gait characteristics during the stance phase of gait in hip osteoarthritis patients not eligible for hip replacement surgery. First, compared to healthy controls, and second, when categorized into two subgroups of radiographic severity defined from a minimal joint space of ≤/>2 mm. Sagittal plane kinematics and kinetics of the hip, knee and ankle joint were calculated for total joint excursion throughout the stance phase, as well as from the specific events initial contact, midstance, peak hip extension and toe-off following 3D gait analysis. In addition, the Western Ontario and McMaster Universities Osteoarthritis Index, passive hip range of motion, and isokinetic muscle strength of hip and knee flexion and extension were included as secondary outcomes. Data were checked for normality and differences evaluated with the independent Student's t-test, Welch's t-test and the independent Mann-Whitney U-test. A binary logistic regression model was used in order to control for velocity in key variables. Fourty-eight hip osteoarthritis patients and 22 controls were included in the final material. The patients walked significantly slower than the controls (p=0.002), revealed significantly reduced joint excursions of the hip (p<0.001) and knee (p=0.011), and a reduced hip flexion moment at midstance and peak hip extension (p<0.001). Differences were primarily manifested during the latter 50% of stance, and were persistent when controlling for velocity. Subgroup analyses of patients with minimal joint space ≤/>2 mm suggested that the observed deviations were more pronounced in patients with greater radiographic severity. The biomechanical

Clinical Examination Results in Individuals With Functional Ankle Instability and Ankle-Sprain Copers

PubMed Central

Wright, Cynthia J.; Arnold, Brent L.; Ross, Scott E.; Ketchum, Jessica; Ericksen, Jeffrey; Pidcoe, Peter

2013-01-01

Context: Why some individuals with ankle sprains develop functional ankle instability and others do not (ie, copers) is unknown. Current understanding of the clinical profile of copers is limited. Objective: To contrast individuals with functional ankle instability (FAI), copers, and uninjured individuals on both self-reported variables and clinical examination findings. Design: Cross-sectional study. Setting: Sports medicine research laboratory. Patients or Other Participants: Participants consisted of 23 individuals with a history of 1 or more ankle sprains and at least 2 episodes of giving way in the past year (FAI: Cumberland Ankle Instability Tool [CAIT] score = 20.52 ± 2.94, episodes of giving way = 5.8 ± 8.4 per month), 23 individuals with a history of a single ankle sprain and no subsequent episodes of instability (copers: CAIT score = 27.74 ± 1.69), and 23 individuals with no history of ankle sprain and no instability (uninjured: CAIT score = 28.78 ± 1.78). Intervention(s): Self-reported disability was recorded using the CAIT and Foot and Ankle Ability Measure for Activities of Daily Living and for Sports. On clinical examination, ligamentous laxity and tenderness, range of motion (ROM), and pain at end ROM were recorded. Main Outcome Measure(s): Questionnaire scores for the CAIT, Foot and Ankle Ability Measure for Activities of Daily Living and for Sports, ankle inversion and anterior drawer laxity scores, pain with palpation of the lateral ligaments, ankle ROM, and pain at end ROM. Results: Individuals with FAI had greater self-reported disability for all measures (P < .05). On clinical examination, individuals with FAI were more likely to have greater talar tilt laxity, pain with inversion, and limited sagittal-plane ROM than copers (P < .05). Conclusions: Differences in both self-reported disability and clinical examination variables distinguished individuals with FAI from copers at least 1 year after injury. Whether the deficits could be detected

Changing Sagittal-Plane Landing Styles to Modulate Impact and Tibiofemoral Force Magnitude and Directions Relative to the Tibia

PubMed Central

Shimokochi, Yohei; Ambegaonkar, Jatin P.; Meyer, Eric G.

2016-01-01

Context: Ground reaction force (GRF) and tibiofemoral force magnitudes and directions have been shown to affect anterior cruciate ligament loading during landing. However, the kinematic and kinetic factors modifying these 2 forces during landing are unknown. Objective: To clarify the intersegmental kinematic and kinetic links underlying the alteration of the GRF and tibiofemoral force vectors secondary to changes in the sagittal-plane body position during single-legged landing. Design: Crossover study. Setting: Laboratory. Patients or Other Participants: Twenty recreationally active participants (age = 23.4 ± 3.6 years, height = 171.0 ± 9.4 cm, mass = 73.3 ± 12.7 kg). Intervention(s): Participants performed single-legged landings using 3 landing styles: self-selected landing (SSL), body leaning forward and landing on the toes (LFL), and body upright with flat-footed landing (URL). Three-dimensional kinetics and kinematics were recorded. Main Outcome Measure(s): Sagittal-plane tibial inclination and knee-flexion angles, GRF magnitude and inclination angles relative to the tibia, and proximal tibial forces at peak tibial axial forces. Results: The URL resulted in less time to peak tibial axial forces, smaller knee-flexion angles, and greater magnitude and a more anteriorly inclined GRF vector relative to the tibia than did the SSL. These changes led to the greatest peak tibial axial and anterior shear forces in the URL among the 3 landing styles. Conversely, the LFL resulted in longer time to peak tibial axial forces, greater knee-flexion angles, and reduced magnitude and a more posteriorly inclined GRF vector relative to the tibia than the SSL. These changes in LFL resulted in the lowest peak tibial axial and largest posterior shear forces among the 3 landing styles. Conclusions: Sagittal-plane intersegmental kinematic and kinetic links strongly affected the magnitude and direction of GRF and tibiofemoral forces during the impact phase of single-legged landing

1975 Memorial Award Paper. Image generation and display techniques for CT scan data. Thin transverse and reconstructed coronal and sagittal planes.

PubMed

Glenn, W V; Johnston, R J; Morton, P E; Dwyer, S J

1975-01-01

The various limitations to computerized axial tomographic (CT) interpretation are due in part to the 8-13 mm standard tissue plane thickness and in part to the absence of alternative planes of view, such as coronal or sagittal images. This paper describes a method for gathering multiple overlapped 8 mm transverse sections, subjecting these data to a deconvolution process, and then displaying thin (1 mm) transverse as well as reconstructed coronal and sagittal CT images. Verification of the deconvolution technique with phantom experiments is described. Application of the phantom results to human post mortem CT scan data illustrates this method's faithful reconstruction of coronal and sagittal tissue densities when correlated with actual specimen photographs of a sectioned brain. A special CT procedure, limited basal overlap scanning, is proposed for use on current first generation CT scanners without hardware modification.

[Evaluation of three methods for constructing craniofacial mid-sagittal plane based on the cone beam computed tomography].

PubMed

Wang, S W; Li, M; Yang, H F; Zhao, Y J; Wang, Y; Liu, Y

2016-04-18

To compare the accuracyof interactive closet point (ICP) algorithm, Procrustes analysis (PA) algorithm,and a landmark-independent method to construct the mid-sagittal plane (MSP) of the cone beam computed tomography.To provide theoretical basis for establishing coordinate systemof CBCT images and symmetric analysis. Ten patients were selected and scanned by CBCT before orthodontic treatment.The scan data was imported into Mimics 10.0 to reconstructthree dimensional skulls.And the MSP of each skull was generated by ICP algorithm, PA algorithm and landmark-independent method. MSP extracted by ICP algorithm or PA algorithm involvedthree steps. First, the 3D skull processing was performed by reverse engineering software geomagic studio 2012 to obtain the mirror skull. Then, the original and its mirror skull was registered separately by ICP algorithm in geomagic studio 2012 and PA algorithm in NX Imageware 11.0. Finally, the registered data were united into new data to calculate the MSP of the originaldata in geomagic studio 2012. The mid-sagittal plane was determined by SELLA (S), nasion (N), basion (Ba) as traditional landmark-dependent methodconducted in software InVivoDental 5.0. The distance from 9 pairs of symmetric anatomical marked points to three sagittal plane were measured and calculated to compare the differences of the absolute value. The one-way ANOVA test was used to analyze the variable differences among the 3 MSPs. The pairwise comparison was performed with LSD method. MSPs calculated by the three methods were available for clinic analysis, which could be concluded from the front view.However, there was significant differences among the distances from the 9 pairs of symmetric anatomical marked points to the MSPs (F=10.932,P=0.001).LSD test showed there was no significant difference between the ICP algorithm and landmark-independent method (P=0.11), while there was significant difference between the PA algorithm and landmark-independent methods (P=0

A system for the analysis of foot and ankle kinematics during gait.

PubMed

Kidder, S M; Abuzzahab, F S; Harris, G F; Johnson, J E

1996-03-01

A five-camera Vicon (Oxford Metrics, Oxford, England) motion analysis system was used to acquire foot and ankle motion data. Static resolution and accuracy were computed as 0.86 +/- 0.13 mm and 98.9%, while dynamic resolution and accuracy were 0.1 +/- 0.89 and 99.4% (sagittal plane). Spectral analysis revealed high frequency noise and the need for a filter (6 Hz Butterworth low-pass) as used in similar clinical situations. A four-segment rigid body model of the foot and ankle was developed. The four rigid body foot model segments were 1) tibia and fibula, 2) calcaneus, talus, and navicular, 3) cuneiforms, cuboid, and metatarsals, and 4) hallux. The Euler method for describing relative foot and ankle segment orientation was utilized in order to maintain accuracy and ease of clinical application. Kinematic data from a single test subject are presented.

The effect of age and speed on foot and ankle kinematics assessed using a 4-segment foot model

PubMed Central

van Hoeve, Sander; Leenstra, Bernard; Willems, Paul; Poeze, Martijn; Meijer, Kenneth

2017-01-01

Abstract Background: The effects of age and speed on foot and ankle kinematics in gait studies using foot models are not fully understood, whereas this can have significant influence. We analyzed these variables with the 4-segment Oxford foot model. Methods: Twenty-one healthy subjects (aged 20–65 years) were recruited for gait analysis. The effect of speed on foot and ankle kinematics was assessed by comparing results during slow walking and fast walking. To assess the effect of age, a group of 13 healthy young adults (aged 20–24 years) were compared with a group of 8 older adults (aged 53–65 years). Also, the interaction between age and speed was analyzed. Results: Regarding speed, there was a significant difference between forefoot/hindfoot motion in the sagittal plane (flexion/extension) during both loading- and push-off phase (P = .004, P < .001). Between hindfoot/tibia, there was a significant difference for all parameters except for motion in the sagittal plane (flexion/extension) during push-off phase (P = .5). Age did not significantly influence kinematics. There was no interaction between age and speed. Conclusion: Our analysis found that speed significantly influenced the kinematic outcome parameters. This was more pronounced in the ankle joint. In contrast, no significant differences were found between younger and older healthy subjects. PMID:28858109

A gait retraining system using augmented-reality to modify footprint parameters: Effects on lower-limb sagittal-plane kinematics.

PubMed

Bennour, Sami; Ulrich, Baptiste; Legrand, Thomas; Jolles, Brigitte M; Favre, Julien

2018-01-03

Improving lower-limb flexion/extension angles during walking is important for the treatment of numerous pathologies. Currently, these gait retraining procedures are mostly qualitative, often based on visual assessment and oral instructions. This study aimed to propose an alternative method combining motion capture and display of target footprints on the floor. The second objectives were to determine the error in footprint modifications and the effects of footprint modifications on lower-limb flexion/extension angles. An augmented-reality system made of an optoelectronic motion capture device and video projectors displaying target footprints on the floor was designed. 10 young healthy subjects performed a series of 27 trials, consisting of increased and decreased amplitudes in stride length, step width and foot progression angle. 11 standard features were used to describe and compare lower-limb flexion/extension angles among footprint modifications. Subjects became accustomed to walk on target footprints in less than 10 min, with mean (± SD) precision of 0.020 ± 0.002 m in stride length, 0.022 ± 0.006 m in step width, and 2.7 ± 0.6° in progression angle. Modifying stride length had significant effects on 3/3 hip, 2/4 knee and 4/4 ankle features. Similarly, step width and progression angle modifications affected 2/3 and 1/3 hip, 2/4 and 1/4 knee as well as 3/4 and 2/4 ankle features, respectively. In conclusion, this study introduced an augmented-reality method allowing healthy subjects to modify their footprint parameters rapidly and precisely. Walking with modified footprints changed lower-limb sagittal-plane kinematics. Further research is needed to design rehabilitation protocols for specific pathologies. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Proposal of New Reference System for the Standard Axial, Sagittal, Coronal Planes of Brain Based on the Serially-Sectioned Images

PubMed Central

Park, Jin Seo; Park, Hyo Seok; Shin, Dong Sun; Har, Dong-Hwan; Cho, Zang-Hee; Kim, Young-Bo; Han, Jae-Yong; Chi, Je-Geun

2010-01-01

Sectional anatomy of human brain is useful to examine the diseased brain as well as normal brain. However, intracerebral reference points for the axial, sagittal, and coronal planes of brain have not been standardized in anatomical sections or radiological images. We made 2,343 serially-sectioned images of a cadaver head with 0.1 mm intervals, 0.1 mm pixel size, and 48 bit color and obtained axial, sagittal, and coronal images based on the proposed reference system. This reference system consists of one principal reference point and two ancillary reference points. The two ancillary reference points are the anterior commissure and the posterior commissure. And the principal reference point is the midpoint of two ancillary reference points. It resides in the center of whole brain. From the principal reference point, Cartesian coordinate of x, y, z could be made to be the standard axial, sagittal, and coronal planes. PMID:20052359

Radiological evaluation of ankle arthrodesis with Ilizarov fixation compared to internal fixation.

PubMed

Morasiewicz, Piotr; Dejnek, Maciej; Urbański, Wiktor; Dragan, Szymon Łukasz; Kulej, Mirosław; Dragan, Szymon Feliks

2017-07-01

We asked whether the type of ankle joint arthrodesis stabilization will affect: (1) rate of union, (2) rate of adjacted-joint arthritis, (3) malalignment of the ankle joint. We retrospectively radiological studied 62 patients who underwent ankle arthrodesis with Ilizarov external fixator stabilization (group 1,n=29) or internal stabilization (group 2,n=33) from 2006 to 2015. Radiologic outcomes were mesure by: (1) rate of union, (2) rate of adjacent-joint arthritis, (3) malalignment of the ankle joint. The Levene's test,Mann-Whitney U test and Students t-test were used to the statistical analyses. Ankle fusion was achieved in 100% of patients treated with external fixation and in 88% with internal stabilization. Desired frontal plane alignment was achieved in 100% of patients with external fixation and 76% with internal stabilization. Desired sagittal plane alignment was achieved in 100% of external fixation and 85% of internal stabilization. A total of 14 (48.3%) patients from group 1 showed a radiographic evidence of pre-existing adjacent-joint OA. The radiographic evidence of pre-existing adjacent-joint OA was also found in 27(81.8%) subjects from group 2. Alterations of adjacent joints were also found on postoperative radiograms of 19 (65.5%) patients subjected to Ilizarov fixation and in all 33 patients from group 2. Ilizarov fixation of ankle arthrodesis is associated with lower prevalence of adjacent-joint OA and ankle joint misalignment,and with higher fusion rates than after internal fixation.Although achieving a complex ankle fusion is generally challenging,radiological outcomes after fixation with the Ilizarov apparatus are better than after internal stabilization. Copyright © 2017 Elsevier Ltd. All rights reserved.

Agreement between fiber optic and optoelectronic systems for quantifying sagittal plane spinal curvature in sitting.

PubMed

Cloud, Beth A; Zhao, Kristin D; Breighner, Ryan; Giambini, Hugo; An, Kai-Nan

2014-07-01

Spinal posture affects how individuals function from a manual wheelchair. There is a need to directly quantify spinal posture in this population to ultimately improve function. A fiber optic system, comprised of an attached series of sensors, is promising for measuring large regions of the spine in individuals sitting in a wheelchair. The purpose of this study was to determine the agreement between fiber optic and optoelectronic systems for measuring spinal curvature, and describe the range of sagittal plane spinal curvatures in natural sitting. Able-bodied adults (n = 26, 13 male) participated. Each participant assumed three sitting postures: natural, slouched (accentuated kyphosis), and extension (accentuated lordosis) sitting. Fiber optic (ShapeTape) and optoelectronic (Optotrak) systems were applied to the skin over spinous processes from S1 to C7 and used to measure sagittal plane spinal curvature. Regions of kyphosis and lordosis were identified. A Cobb angle-like method was used to quantify lordosis and kyphosis. Generalized linear model and Bland-Altman analyses were used to assess agreement. A strong correlation exists between curvature values obtained with Optotrak and ShapeTape (R(2) = 0.98). The mean difference between Optotrak and ShapeTape for kyphosis in natural, extension, and slouched postures was 4.30° (95% LOA: -3.43 to 12.04°), 3.64° (95% LOA: -1.07 to 8.36°), and 4.02° (95% LOA: -2.80 to 10.84°), respectively. The mean difference for lordosis, when present, in natural and extension postures was 2.86° (95% LOA: -1.18 to 6.90°) and 2.55° (95% LOA: -3.38 to 8.48°), respectively. In natural sitting, the mean ± SD of kyphosis values was 35.07 ± 6.75°. Lordosis was detected in 8/26 participants: 11.72 ± 7.32°. The fiber optic and optoelectronic systems demonstrate acceptable agreement for measuring sagittal plane thoracolumbar spinal curvature. Copyright © 2014 Elsevier B.V. All rights reserved.

Agreement between Fiber Optic and Optoelectronic Systems for Quantifying Sagittal Plane Spinal Curvature in Sitting

PubMed Central

Cloud, Beth A.; Zhao, Kristin D.; Breighner, Ryan; Giambini, Hugo; An, Kai-Nan

2014-01-01

Spinal posture affects how individuals function from a manual wheelchair. There is a need to directly quantify spinal posture in this population to ultimately improve function. A fiber optic system, comprised of an attached series of sensors, is promising for measuring large regions of the spine in individuals sitting in a wheelchair. The purpose of this study was to determine the agreement between fiber optic and optoelectronic systems for measuring spinal curvature, and describe the range of sagittal plane spinal curvatures in natural sitting. Able-bodied adults (n=26, 13 male) participated. Each participant assumed three sitting postures: natural, slouched (accentuated kyphosis), and extension (accentuated lordosis) sitting. Fiber optic (ShapeTape) and optoelectronic (Optotrak) systems were applied to the skin over spinous processes from S1 to C7 and used to measure sagittal plane spinal curvature. Regions of kyphosis and lordosis were identified. A Cobb angle-like method was used to quantify lordosis and kyphosis. Generalized linear model and Bland-Altman analyses were used to assess agreement. A strong correlation exists between curvature values obtained with Optotrak and ShapeTape (R2=0.98). The mean difference between Optotrak and ShapeTape for kyphosis in natural, extension, and slouched postures was 4.30° (95%LOA: −3.43-12.04°), 3.64° (95%LOA: −1.07-8.36°), and 4.02° (95%LOA: −2.80-10.84°), respectively. The mean difference for lordosis, when present, in natural and extension postures is 2.86° (95%LOA: −1.18-6.90°) and 2.55° (95%LOA: −3.38-8.48°), respectively. In natural sitting, the mean±SD of kyphosis values was 35.07± 6.75°. Lordosis was detected in 8/26 participants: 11.72±7.32°. The fiber optic and optoelectronic systems demonstrate acceptable agreement for measuring sagittal plane thoracolumbar spinal curvature. PMID:24909579

Chimpanzee ankle and foot joint kinematics: Arboreal versus terrestrial locomotion.

PubMed

Holowka, Nicholas B; O'Neill, Matthew C; Thompson, Nathan E; Demes, Brigitte

2017-09-01

Many aspects of chimpanzee ankle and midfoot joint morphology are believed to reflect adaptations for arboreal locomotion. However, terrestrial travel also constitutes a significant component of chimpanzee locomotion, complicating functional interpretations of chimpanzee and fossil hominin foot morphology. Here we tested hypotheses of foot motion and, in keeping with general assumptions, we predicted that chimpanzees would use greater ankle and midfoot joint ranges of motion during travel on arboreal supports than on the ground. We used a high-speed motion capture system to measure three-dimensional kinematics of the ankle and midfoot joints in two male chimpanzees during three locomotor modes: terrestrial quadrupedalism on a flat runway, arboreal quadrupedalism on a horizontally oriented tree trunk, and climbing on a vertically oriented tree trunk. Chimpanzees used relatively high ankle joint dorsiflexion angles during all three locomotor modes, although dorsiflexion was greatest in arboreal modes. They used higher subtalar joint coronal plane ranges of motion during terrestrial and arboreal quadrupedalism than during climbing, due in part to their use of high eversion angles in the former. Finally, they used high midfoot inversion angles during arboreal locomotor modes, but used similar midfoot sagittal plane kinematics across all locomotor modes. The results indicate that chimpanzees use large ranges of motion at their various ankle and midfoot joints during both terrestrial and arboreal locomotion. Therefore, we argue that chimpanzee foot anatomy enables a versatile locomotor repertoire, and urge caution when using foot joint morphology to reconstruct arboreal behavior in fossil hominins. © 2017 Wiley Periodicals, Inc.

Ankle joint function during walking in tophaceous gout: A biomechanical gait analysis study.

PubMed

Carroll, Matthew; Boocock, Mark; Dalbeth, Nicola; Stewart, Sarah; Frampton, Christopher; Rome, Keith

2018-04-17

The foot and ankle are frequently affected in tophaceous gout, yet kinematic and kinetic changes in this region during gait are unknown. The aim of the study was to evaluate ankle biomechanical characteristics in people with tophaceous gout using three-dimensional gait analysis. Twenty-four participants with tophaceous gout were compared with 24 age-and sex-matched control participants. A 9-camera motion analysis system and two floor-mounted force plates were used to calculate kinematic and kinetic parameters. Peak ankle joint angular velocity was significantly decreased in participants with gout (P < 0.01). No differences were found for ankle ROM in either the sagittal (P = 0.43) or frontal planes (P = 0.08). No differences were observed between groups for peak ankle joint power (P = 0.41), peak ankle joint force (P = 0.25), peak ankle joint moment (P = 0.16), timing for peak ankle joint force (P = 0.81), or timing for peak ankle joint moment (P = 0.16). Three dimensional gait analysis demonstrated that ankle joint function does not change in people with gout. People with gout demonstrated a reduced peak ankle joint angular velocity which may reflect gait-limiting factors and adaptations from the high levels of foot pain, impairment and disability experienced by this population. Copyright © 2018 Elsevier B.V. All rights reserved.

Weight-bearing computed tomography findings in varus ankle osteoarthritis: abnormal internal rotation of the talus in the axial plane.

PubMed

Kim, Ji-Beom; Yi, Young; Kim, Jae-Young; Cho, Jae-Ho; Kwon, Min-Soo; Choi, Seung-Hyuk; Lee, Woo-Chun

2017-08-01

To assess the incidence of abnormal internal rotation of the talus in the axial plane in patients with varus ankle osteoarthritis, and to determine whether this incidence differs from the severity of varus ankle osteoarthritis (moderate versus severe). We retrospectively evaluated weight-bearing computed tomography (CT) and plain radiographs of 52 ankles with no abnormalities (control group) and 96 ankles with varus osteoarthritis (varus-OA group), which were further stratified into a moderate-OA subgroup (50 ankles) and a severe-OA subgroup (46 ankles). A new radiographic parameter on weight-bearing CT, the talus rotation ratio, was used to assess the rotation of the talus in the axial plane. The normal range of the talus rotation ratio was defined as the 95% prediction interval for talus rotation ratio values in the control group. Abnormal internal rotation of the talus was defined for talus rotation ratio values above the normal range. We determined the incidence of abnormal internal rotation of the talus in the varus-OA group, moderate-OA subgroup, and severe-OA subgroup. In the varus-OA group, the incidence of abnormal internal rotation of the talus was 45% (43 ankles), which corresponded to an incidence of 32% (16 ankles) in the moderate-OA subgroup and 59% (27 ankles) in the severe-OA subgroup (p = 0.013). Our study demonstrates that abnormal internal rotation of the talus occurs in patients with varus ankle osteoarthritis, and is more frequently noted in severe than in moderate varus ankle osteoarthritis.

The correlation of the morphological changes of ankle point and ankle joint function after surgery on the Ruedi-Allgouer type III Pilon fracture: A case series study.

PubMed

Zhou, Yifei; Cai, Leyi; Lu, Xiaolang; Yu, Yang; Hong, Jianjun

2017-08-01

To analyze the relationship between imaging findings and postoperative curative effect by measuring the morphology of the ankle mortise in patients with the Ruedi-Allgouer type III Pilon fractures. Forty-seven patients with Ruedi-Allgouer type III Pilon fractures who underwent surgical treatment from January 2011 to January 2015 were retrospectively analyzed. At the last follow-up, x-rays of the affected ankle and the healthy side were measured. According to the Kitaoka score of ankle joint function at the last follow-up. All patients were followed up for 18-24 months (mean 21 months). This study demonstrated that compared with the healthy side, the index of the width, depth, and coronal/sagittal angles of the ankle mortise were significantly different (P < 0.05) in the 47 patients except for the index of height (P > 0.05). According to the Kitaoka score, the difference between the affected and the healthy sides of each index of the ankle mortise was compared between the 3 groups. That is, the intraoperative treatment of the width and depth of the ankle mortise as well as the coronal and sagittal angles of the ankle mortise were significantly correlated with the postoperative curative effect. The intraoperative treatment of ankle mortise width, depth, and ankle coronal/sagittal angle in patients with severe Pilon fractures has a significant impact on postoperative efficacy. In order to prevent the occurrence of traumatic arthritis, the anatomical morphology of the ankle should be restored as much as possible in the course of surgery. Copyright © 2017. Published by Elsevier Ltd.

[Influence of Restricting the Ankle Joint Complex Motions on Gait Stability of Human Body].

PubMed

Li, Yang; Zhang, Junxia; Su, Hailong; Wang, Xinting; Zhang, Yan

2016-10-01

The purpose of this study is to determine how restricting inversion-eversion and pronation-supination motions of the ankle joint complex influences the stability of human gait.The experiment was carried out on a slippery level ground walkway.Spatiotemporal gait parameter,kinematics and kinetics data as well as utilized coefficient of friction(UCOF)were compared between two conditions,i.e.with restriction of the ankle joint complex inversion-eversion and pronation-supination motions(FIXED)and without restriction(FREE).The results showed that FIXED could lead to a significant increase in velocity and stride length and an obvious decrease in double support time.Furthermore,FIXED might affect the motion angle range of knee joint and ankle joint in the sagittal plane.In FIXED condition,UCOF was significantly increased,which could lead to an increase of slip probability and a decrease of gait stability.Hence,in the design of a walker,bipedal robot or prosthetic,the structure design which is used to achieve the ankle joint complex inversion-eversion and pronation-supination motions should be implemented.

Progression of spinal deformity in wheelchair-dependent patients with Duchenne muscular dystrophy who are not treated with steroids: coronal plane (scoliosis) and sagittal plane (kyphosis, lordosis) deformity.

PubMed

Shapiro, F; Zurakowski, D; Bui, T; Darras, B T

2014-01-01

We determined the frequency, rate and extent of development of scoliosis (coronal plane deformity) in wheelchair-dependent patients with Duchenne muscular dystrophy (DMD) who were not receiving steroid treatment. We also assessed kyphosis and lordosis (sagittal plane deformity). The extent of scoliosis was assessed on sitting anteroposterior (AP) spinal radiographs in 88 consecutive non-ambulatory patients with DMD. Radiographs were studied from the time the patients became wheelchair-dependent until the time of spinal fusion, or the latest assessment if surgery was not undertaken. Progression was estimated using a longitudinal mixed-model regression analysis to handle repeated measurements. Scoliosis ≥ 10° occurred in 85 of 88 patients (97%), ≥ 20° in 78 of 88 (89%) and ≥ 30° in 66 of 88 patients (75%). The fitted longitudinal model revealed that time in a wheelchair was a highly significant predictor of the magnitude of the curve, independent of the age of the patient (p < 0.001). Scoliosis developed in virtually all DMD patients not receiving steroids once they became wheelchair-dependent, and the degree of deformity deteriorated over time. In general, scoliosis increased at a constant rate, beginning at the time of wheelchair-dependency (p < 0.001). In some there was no scoliosis for as long as three years after dependency, but scoliosis then developed and increased at a constant rate. Some patients showed a rapid increase in the rate of progression of the curve after a few years - the clinical phenomenon of a rapidly collapsing curve over a few months. A sagittal plane kyphotic deformity was seen in 37 of 60 patients (62%) with appropriate radiographs, with 23 (38%) showing lumbar lordosis (16 (27%) abnormal and seven (11%) normal). This study provides a baseline to assess the effects of steroids and other forms of treatment on the natural history of scoliosis in patients with DMD, and an approach to assessing spinal deformity in the coronal and

The effects of a semi-rigid ankle brace on a simulated isolated subtalar joint instability.

PubMed

Choisne, Julie; Hoch, Matthew C; Bawab, Sebastian; Alexander, Ian; Ringleb, Stacie I

2013-12-01

Subtalar joint instability is hypothesized to occur after injuries to the calcaneofibular ligament (CFL) in isolation or in combination with the cervical and the talocalcaneal interosseous ligaments. A common treatment for hindfoot instability is the application of an ankle brace. However, the ability of an ankle brace to promote subtalar joint stability is not well established. We assessed the kinematics of the subtalar joint, ankle, and hindfoot in the presence of isolated subtalar instability, investigated the effect of bracing in a CFL deficient foot and with a total rupture of the intrinsic ligaments, and evaluated how maximum inversion range of motion is affected by the position of the ankle in the sagittal plane. Kinematics from nine cadaveric feet were collected with the foot placed in neutral, dorsiflexion, and plantar flexion. Motion was applied with and without a brace on an intact foot and after sequentially sectioning the CFL and the intrinsic ligaments. Isolated CFL sectioning increased ankle joint inversion, while sectioning the CFL and intrinsic ligaments affected subtalar joint stability. The brace limited inversion at the subtalar and ankle joints. Additionally, examining the foot in dorsiflexion reduced ankle and subtalar joint motion. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Effects of Prophylactic Ankle Supports on Vertical Ground Reaction Force During Landing: A Meta-Analysis.

PubMed

Niu, Wenxin; Feng, Tienan; Wang, Lejun; Jiang, Chenghua; Zhang, Ming

2016-03-01

There has been much debate on how prophylactic ankle supports (PASs) may influence the vertical ground reaction force (vGRF) during landing. Therefore, the primary aims of this meta-analysis were to systematically review and synthesize the effect of PASs on vGRF, and to understand how PASs affect vGRF peaks (F1, F2) and the time from initial contact to peak loading (T1, T2) during landing. Several key databases, including Scopus, Cochrane, Embase, PubMed, ProQuest, Medline, Ovid, Web of Science, and the Physical Activity Index, were used for identifying relevant studies published in English since inception to April 1, 2015. The computerized literature search and cross-referencing the citation list of the articles yielded 3,993 articles. Criteria for inclusion required that 1) the study was conducted on healthy adults; 2) the subject number and trial number were known; 3) the subjects performed landing with and without PAS; 4) the landing movement was in the sagittal plane; 5) the comparable vGRF parameters were reported; and 6) the F1 and F2 must be normalized to the subject's body weight. After the removal of duplicates and irrelevant articles, 6, 6, 15 and 11 studies were respectively pooled for outcomes of F1, T1, F2 and T2. This study found a significantly increased F2 (.03 BW, 95% CI: .001, .05) and decreased T1 (-1.24 ms, 95% CI: -1.77, -.71) and T2 (-3.74 ms, 95% CI: -4.83, -2.65) with the use of a PAS. F1 was not significantly influenced by the PAS. Heterogeneity was present in some results, but there was no evidence of publication bias for any outcome. These changes represented deterioration in the buffering characteristics of the joint. An ideal PAS design should limit the excessive joint motion of ankle inversion, while allowing a normal range of motion, especially in the sagittal plane. Key pointsPAS can effectively protect the ligamentous structure from spraining by providing mechanical support and cutaneous proprioceptive benefits.Using of PAS can

The Effects of Frontal- and Sagittal-Plane Plyometrics on Change-of-Direction Speed and Power in Adolescent Female Basketball Players.

PubMed

McCormick, Brian T; Hannon, James C; Newton, Maria; Shultz, Barry; Detling, Nicole; Young, Warren B

2016-01-01

Plyometrics is a popular training modality for basketball players to improve power and change-of-direction speed. Most plyometric training has used sagittal-plane exercises, but improvements in change-of-direction speed have been greater in multi-direction programs. To determine the benefits of a 6-wk frontal-plane plyometric (FPP) training program compared with a 6-wk sagittal-plane plyometric (SPP) training program with regard to power and change-of-direction speed. Fourteen female varsity high school basketball players participated in the study. Multiple 2 × 2 repeated-measures ANOVAs were used to determine differences for the FPP and SPP groups from preintervention to postintervention on 4 tests of power and 2 tests of change-of-direction speed. There was a group main effect for time in all 6 tests. There was a significant group × time interaction effect in 3 of the 6 tests. The SPP improved performance of the countermovement vertical jump more than the FPP, whereas the FPP improved performance of the lateral hop (left) and lateral-shuffle test (left) more than the SPP. The standing long jump, lateral hop (right), and lateral-shuffle test (right) did not show a significant interaction effect. These results suggest that basketball players should incorporate plyometric training in all planes to improve power and change-of-direction speed.

Prophylactic Ankle Braces and the Kinematics and Kinetics of Half-Squat Parachute Landing.

PubMed

Wu, Di; Zheng, Chao; Wu, Ji; Hu, Tan; Huang, Rongrong; Wang, Lizhen; Fan, Yubo

2018-02-01

The objective of the study was to investigate the effects of dropping heights and prophylactic ankle braces on ankle joint biomechanics during half-squat parachute landing from two different heights. There were 30 male elite paratroopers with formal parachute landing training and more than 2 yr of parachute jumping experience who were recruited for this study. The subjects tested three different ankle brace conditions (no-brace, elastic brace, semirigid brace). Each subject was instructed to jump off a platform from two different heights of 0.4 m and 0.8 m, and land on a force plate in a half-squat posture. The Vicon 3D motion capture system and force plate were used to record and calculate kinematic and kinetic data. Dropping height had a significant effect on peak vertical ground reaction force (vGRF), maximum ankle angular displacement, and time to vGRF. As compared with the no-brace group, use of an elastic ankle brace significantly reduced peak vGRF by 18.57% and both braces significantly reduced the maximal angular displacements of dorsiflexion. The semirigid brace provided greater restriction against maximal angular displacement of inversion. The elastic and semirigid ankle braces both effectively restricted motion stability of the ankle joint in the sagittal plane, and the semirigid ankle brace prevented excessive inversion, although the comfort of this device should be improved overall.Wu D, Zheng C, Wu J, Hu T, Huang R, Wang L, Fan Y. Prophylactic ankle braces and the kinematics and kinetics of half-squat parachute landing. Aerosp Med Hum Perform. 2018; 89(2):141-146.

Femoro-tibial kinematics after TKA in fixed- and mobile-bearing knees in the sagittal plane.

PubMed

Daniilidis, Kiriakos; Höll, Steffen; Gosheger, Georg; Dieckmann, Ralf; Martinelli, Nicolo; Ostermeier, Sven; Tibesku, Carsten O

2013-10-01

Lack of the anterior cruciate ligament in total knee arthroplasty results in paradoxical movement of the femur as opposed to the tibia under deep flexion. Total knee arthroplasty with mobile-bearing inlays has been developed to provide increased physiological movement of the knee joint and to reduce polyethylene abrasion. The aim of this study was to perform an in vitro analysis of the kinematic movement in the sagittal plane in order to show differences between fixed- and mobile-bearing TKA in comparison with the natural knee joint. Seven knee joints of human cadaver material were used in a laboratory experiment. Fixed- and mobile-bearing inlays were tested in sequences under isokinetic extension in so-called kinemator for knee joints, which can simulate muscular traction power by the use of hydraulic cylinders, which crossover the knee joint. As a target parameter, the a.p. translation of the tibio-femoral relative movement was measured in the sagittal plane under ultrasound (Zebris) control. The results show a reduced tibial a.p. translation in relation to the femur in the bearing group compared to the natural joint. In the Z-axis, between 110° and 50° of flexion, linear movement decreases towards caudal movement under extension. Admittedly, the study did not show differences in the movement pattern between "mobile-bearing" and "fixed-bearing" prostheses. Results of this study cannot prove functional advantages of mobile-bearing prostheses for the knee joint kinematic after TKA. Both types of prostheses show typical kinematics of an anterior instability, hence they were incapable of performing physiological movement.

Satisfactory rate of post-processing visualization of fetal cerebral axial, sagittal, and coronal planes from three-dimensional volumes acquired in routine second trimester ultrasound practice by sonographers of peripheral centers.

PubMed

Rizzo, Giuseppe; Pietrolucci, Maria Elena; Capece, Giuseppe; Cimmino, Ernesto; Colosi, Enrico; Ferrentino, Salvatore; Sica, Carmine; Di Meglio, Aniello; Arduini, Domenico

2011-08-01

The aim of this study was to evaluate the feasibility to visualize central nervous system (CNS) diagnostic planes from three-dimensional (3D) brain volumes obtained in ultrasound facilities with no specific experience in fetal neurosonography. Five sonographers prospectively recorded transabdominal 3D CNS volumes starting from an axial approach on 500 consecutive pregnancies at 19-24 weeks of gestation undergoing routine ultrasound examination. Volumes were sent to the referral center (Department of Obstetrics and Gynecology, Università Roma Tor Vergata, Italy) and two independent reviewers with experience in 3D ultrasound assessed their quality in the display of axial, coronal, and sagittal planes. CNS volumes were acquired in 491/500 pregnancies (98.2%). The two reviewers acknowledged the presence of satisfactory images with a visualization rate ranging respectively between 95.1% and 97.14% for axial planes, 73.72% and 87.16% for coronal planes, and 78.41% and 94.29% for sagittal planes. The agreement rate between the two reviewers as expressed by Cohen's kappa coefficient was >0.87 for axial planes, >0.89 for coronal planes, and >0.94 for sagittal planes. The presence of a maternal body mass index >30 alters the probability of achieving satisfactory CNS views, while existence of previous maternal lower abdomen surgery does not affect the quality of the reconstructed planes. CNS volumes acquired by 3D ultrasonography in peripheral centers showed a quality high enough to allow a detailed fetal neurosonogram.

Effect of torso flexion on the lumbar torso extensor muscle sagittal plane moment arms.

PubMed

Jorgensen, Michael J; Marras, William S; Gupta, Purnendu; Waters, Thomas R

2003-01-01

Accurate anatomical inputs for biomechanical models are necessary for valid estimates of internal loading. The magnitude of the moment arm of the lumbar erector muscle group is known to vary as a function of such variables as gender. Anatomical evidence indicates that the moment arms decrease during torso flexion. However, moment arm estimates in biomechanical models that account for individual variability have been derived from imaging studies from supine postures. Quantify the sagittal plane moment arms of the lumbar erector muscle group as a function of torso flexion, and identify individual characteristics that are associated with the magnitude of the moment arms as a function of torso flexion. Utilization of a 0.3 Tesla Open magnetic resonance image (MRI) to image and quantify the moment arm of the right erector muscle group as a function of gender and torso flexion. Axial MRI images through and parallel to each of the lumbar intervertebral discs at four torso flexion angles were obtained from 12 male and 12 female subjects in a lateral recumbent posture. Multivariate analysis of variance was used to investigate the differences in the moment arms at different torso flexion angles, whereas hierarchical linear regression was used to investigate associations with individual anthropometric characteristics and spinal posture. The largest decrease in the lumbar erector muscle group moment arm from neutral to 45-degree flexion occurred at the L5-S1 level (9.7% and 8.9% for men and women, respectively). Measures of spinal curvature (L1-S1 lordosis), body mass and trunk characteristics (depth or circumference) were associated with the varying moment arm at most lumbar levels. The sagittal plane moment arms of the lumbar erector muscle mass decrease as the torso flexes forward. The change in moment arms as a function of torso flexion may have an impact on prediction of spinal loading in biomechanical models.

A 4-week neuromuscular training program and gait patterns at the ankle joint.

PubMed

Coughlan, Garrett; Caulfield, Brian

2007-01-01

Previous research into the rehabilitation of ankle sprains has primarily focused on outcome measures that do not replicate functional activities, thus making it difficult to extrapolate the results relative to the weight-bearing conditions under which most ankle sprains occur. To measure the effects of a training program on gait during walking and running in an active athletic population. Matched-pairs, controlled trial. University motion analysis laboratory. Ten subjects from an athletic population (7 healthy, 3 with functional ankle instability: age = 25.8 +/- 3.9 years, height = 177.6 +/- 6.1 cm, mass = 66.8 +/- 7.4 kg) and 10 controls matched for age, sex, activity, and ankle instability (7 healthy, 3 with functional ankle instability: age = 27.4 +/- 5.8 years, height = 178.7 +/- 10.8 cm, mass = 71.6 +/- 10.0 kg). A 4-week neuromuscular training program undertaken by the treatment group. We measured ankle position and velocity in the frontal (x) and sagittal (y) planes in all subjects during treadmill walking and running for the periods 100 milliseconds before heel strike, at heel strike, and 100 milliseconds after heel strike. A 4-week neuromuscular training program resulted in no significant changes in ankle position or velocity during treadmill walking and running. The mechanisms by which neuromuscular training improves function in normal subjects and those with functional ankle instability do not appear to result in measurable changes in gait kinematics. Our findings raise issues regarding methods of ankle sprain rehabilitation and the measurement of their effectiveness in improving functional activities. Further research in a larger population with functional ankle instability is necessary.

Motion at the Tibial and Polyethylene Component Interface in a Mobile-Bearing Total Ankle Replacement.

PubMed

Lundeen, Gregory A; Clanton, Thomas O; Dunaway, Linda J; Lu, Minggen

2016-08-01

Normal biomechanics of the ankle joint includes sagittal as well as axial rotation. Current understanding of mobile-bearing motion at the tibial-polyethylene interface in total ankle arthroplasty (TAA) is limited to anterior-posterior (AP) motion of the polyethylene component. The purpose of our study was to define the motion of the polyethylene component in relation to the tibial component in a mobile-bearing TAA in both the sagittal and axial planes in postoperative patients. Patients who were a minimum of 12 months postoperative from a third-generation mobile-bearing TAA were identified. AP images were saved at maximum internal and external rotation, and the lateral images were saved in maximum plantarflexion and dorsiflexion. Sagittal range of motion and AP translation of the polyethylene component were measured from the lateral images. Axial rotation was determined by measuring the relative position of the 2 wires within the polyethylene component on AP internal and external rotation imaging. This relationship was compared to a table developed from fluoroscopic images taken at standardized degrees of axial rotation of a nonimplanted polyethylene with the associated length relationship of the 2 imbedded wires. Sixteen patients were included in this investigation, 9 (56%) were male and average age was 68 (range, 49-80) years. Time from surgery averaged 25 (range, 12-38) months. Total sagittal range of motion averaged 23±9 (range, 9-33) degrees. Axial motion for total internal and external rotation of the polyethylene component on the tibial component averaged 6±5 (range, 0-18) degrees. AP translation of the polyethylene component relative to the tibial component averaged 1±1 (range, 0-3) mm. There was no relationship between axial rotation or AP translation of the polyethylene component and ankle joint range of motion (P > .05). To our knowledge, this is the first investigation to measure axial and sagittal motion of the polyethylene component at the tibial

Shoe collar height effect on athletic performance, ankle joint kinematics and kinetics during unanticipated maximum-effort side-cutting performance.

PubMed

Lam, Gilbert Wing Kai; Park, Eun Jung; Lee, Ki-Kwang; Cheung, Jason Tak-Man

2015-01-01

Side-step cutting manoeuvres comprise the coordination between planting and non-planting legs. Increased shoe collar height is expected to influence ankle biomechanics of both legs and possibly respective cutting performance. This study examined the shoe collar height effect on kinematics and kinetics of planting and non-planting legs during an unanticipated side-step cutting. Fifteen university basketball players performed maximum-effort side-step cutting to the left 45° direction or a straight ahead run in response to a random light signal. Seven successful cutting trials were collected for each condition. Athletic performance, ground reaction force, ankle kinematics and kinetics of both legs were analysed using paired t-tests. Results indicated that high-collar shoes resulted in less ankle inversion and external rotation during initial contact for the planting leg. The high-collar shoes also exhibited a smaller ankle range of motion in the sagittal and transverse planes for both legs, respectively. However, no collar effect was found for ankle moments and performance indicators including cutting performance time, ground contact time, propulsion ground reaction forces and impulses. These findings indicated that high-collar shoes altered ankle positioning and restricted ankle joint freedom movements in both legs, while no negative effect was found for athletic cutting performance.

A systematic review of the angular values obtained by computerized photogrammetry in sagittal plane: a proposal for reference values.

PubMed

Krawczky, Bruna; Pacheco, Antonio G; Mainenti, Míriam R M

2014-05-01

Reference values for postural alignment in the coronal plane, as measured by computerized photogrammetry, have been established but not for the sagittal plane. The objective of this study is to propose reference values for angular measurements used for postural analysis in the sagittal plane for healthy adults. Electronic databases (PubMed, BVS, Cochrane, Scielo, and Science Direct) were searched using the following key words: evaluation, posture, photogrammetry, and software. Articles published between 2006 and 2012 that used the PAS/SAPO (postural assessment software) were selected. Another inclusion criterion was the presentation of, at least, one of the following measurements: head horizontal alignment, pelvic horizontal alignment, hip angle, vertical alignment of the body, thoracic kyphosis, and lumbar lordosis. Angle samples of the selected articles were grouped 2 by 2 in relation to an overall average, which made possible total average, variance, and SD calculations. Six articles were included, and the following average angular values were found: 51.42° ± 4.87° (head horizontal alignment), -12.26° ± 5.81° (pelvic horizontal alignment), -6.40° ± 3.86° (hip angle), and 1.73° ± 0.94° (vertical alignment of the body). None of the articles contained the measurements for thoracic kyphosis and lumbar lordosis. The reference values can be adopted as reference for postural assessment in future researches if the same anatomical points are considered. Copyright © 2014 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

Amputation effects on the underlying complexity within transtibial amputee ankle motion

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

Wurdeman, Shane R., E-mail: shanewurdeman@gmail.com; Advanced Prosthetics Center, Omaha, Nebraska 68134; Myers, Sara A.

2014-03-15

The presence of chaos in walking is considered to provide a stable, yet adaptable means for locomotion. This study examined whether lower limb amputation and subsequent prosthetic rehabilitation resulted in a loss of complexity in amputee gait. Twenty-eight individuals with transtibial amputation participated in a 6 week, randomized cross-over design study in which they underwent a 3 week adaptation period to two separate prostheses. One prosthesis was deemed “more appropriate” and the other “less appropriate” based on matching/mismatching activity levels of the person and the prosthesis. Subjects performed a treadmill walking trial at self-selected walking speed at multiple points ofmore » the adaptation period, while kinematics of the ankle were recorded. Bilateral sagittal plane ankle motion was analyzed for underlying complexity through the pseudoperiodic surrogation analysis technique. Results revealed the presence of underlying deterministic structure in both prostheses and both the prosthetic and sound leg ankle (discriminant measure largest Lyapunov exponent). Results also revealed that the prosthetic ankle may be more likely to suffer loss of complexity than the sound ankle, and a “more appropriate” prosthesis may be better suited to help restore a healthy complexity of movement within the prosthetic ankle motion compared to a “less appropriate” prosthesis (discriminant measure sample entropy). Results from sample entropy results are less likely to be affected by the intracycle periodic dynamics as compared to the largest Lyapunov exponent. Adaptation does not seem to influence complexity in the system for experienced prosthesis users.« less

Do ankle orthoses improve ankle proprioceptive thresholds or unipedal balance in older persons with peripheral neuropathy?

PubMed

Son, Jaebum; Ashton-Miller, James A; Richardson, James K

2010-05-01

To determine whether ankle orthoses that provide medial and lateral support, and have been found to decrease gait variability in older persons with peripheral neuropathy, decrease (improve) frontal plane ankle proprioceptive thresholds or increase unipedal stance time in that same population. Observational study in which unipedal stance time was determined with a stopwatch, and frontal plane ankle (inversion and eversion) proprioceptive thresholds were quantified during bipedal stance using a foot cradle system and a series of 100 rotational stimuli, in 11 older neuropathic subjects (8 men; age 72 +/- 7.1 yr) with and without ankle orthoses. The subjects demonstrated no change in combined frontal plane (inversion + eversion) proprioceptive thresholds or unipedal stance time with vs. without the orthoses (1.06 +/- 0.56 vs. 1.13 +/- 0.39 degrees, respectively; P = 0.955 and 6.1 +/- 6.5 vs. 6.2 +/- 5.4 secs, respectively; P = 0.922). Ankle orthoses that provide medial-lateral support do not seem to change ankle inversion/eversion proprioceptive thresholds or unipedal stance time in older persons with diabetic peripheral neuropathy. Previously identified improvements in gait variability using orthoses in this population are therefore likely related to an orthotically induced stiffening of the ankle rather than a change in ankle afferent function.

A 4-Week Neuromuscular Training Program and Gait Patterns at the Ankle Joint

PubMed Central

Coughlan, Garrett; Caulfield, Brian

2007-01-01

Context: Previous research into the rehabilitation of ankle sprains has primarily focused on outcome measures that do not replicate functional activities, thus making it difficult to extrapolate the results relative to the weight-bearing conditions under which most ankle sprains occur. Objective: To measure the effects of a training program on gait during walking and running in an active athletic population. Design: Matched-pairs, controlled trial. Setting: University motion analysis laboratory. Patients or Other Participants: Ten subjects from an athletic population (7 healthy, 3 with functional ankle instability: age = 25.8 ± 3.9 years, height = 177.6 ± 6.1 cm, mass = 66.8 ± 7.4 kg) and 10 controls matched for age, sex, activity, and ankle instability (7 healthy, 3 with functional ankle instability: age = 27.4 ± 5.8 years, height = 178.7 ± 10.8 cm, mass = 71.6 ± 10.0 kg). Intervention(s): A 4-week neuromuscular training program undertaken by the treatment group. Main Outcome Measure(s): We measured ankle position and velocity in the frontal (x) and sagittal (y) planes in all subjects during treadmill walking and running for the periods 100 milliseconds before heel strike, at heel strike, and 100 milliseconds after heel strike. Results: A 4-week neuromuscular training program resulted in no significant changes in ankle position or velocity during treadmill walking and running. Conclusions: The mechanisms by which neuromuscular training improves function in normal subjects and those with functional ankle instability do not appear to result in measurable changes in gait kinematics. Our findings raise issues regarding methods of ankle sprain rehabilitation and the measurement of their effectiveness in improving functional activities. Further research in a larger population with functional ankle instability is necessary. PMID:17597944

The influence of heel height on sagittal plane knee kinematics during landing tasks in recreationally active and athletic collegiate females.

PubMed

Lindenberg, Kelly M; Carcia, Christopher R; Phelps, Amy L; Martin, Robroy L; Burrows, Anne M

2011-09-01

To determine if heel height alters sagittal plane knee kinematics when landing from a forward hop or drop landing. Knee angles close to extension during landing are theorized to increase ACL injury risk in female athletes. Fifty collegiate females performed two single-limb landing tasks while wearing heel lifts of three different sizes (0, 12 & 24 mm) attached to the bottom of a sneaker. Using an electrogoniometer, sagittal plane kinematics (initial contact [KA(IC)], peak flexion [KA(Peak)], and rate of excursion [RE]) were examined. Repeated measures ANOVAs were used to determine the influence of heel height on the dependent measures. Forward hop task- KA(IC) with 0 mm, 12 mm, and 24 mm lifts were 8.88±6.5, 9.38±5.8 and 11.28±7.0, respectively. Significant differences were noted between 0 and 24 mm lift (p<.001) and 12 and 24 mm lifts (p=.003), but not between the 0 and 12 mm conditions (p=.423). KA(Peak) with 0 mm, 12 mm, and 24 mm lifts were 47.08±10.9, 48.18±10.3 and 48.88±9.7, respectively. A significant difference was noted between 0 and 24 mm lift (p=.004), but not between the 0 and 12 mm or 12 and 24 mm conditions (p=.071 and p=.282, respectively). The RE decreased significantly from 2128/sec±52 with the 12 mm lift to 1958/sec±55 with the 24 mm lift (p=.004). RE did not differ from 0 to 12 or 0 to 24 mm lift conditions (p=.351 and p=.086, respectively). Jump-landing task- No significant differences were found in KA(IC) (p=.531), KA(Peak) (p=.741), or the RE (p=.190) between any of the heel lift conditions. The addition of a 24 mm heel lift to the bottom of a sneaker significantly alters sagittal plane knee kinematics upon landing from a unilateral forward hop but not from a drop jump.

Does flip-flop style footwear modify ankle biomechanics and foot loading patterns?

PubMed

Price, Carina; Andrejevas, Vaidas; Findlow, Andrew H; Graham-Smith, Philip; Jones, Richard

2014-01-01

��± 2.1°, p = 0.032). The FitFlop more effectively attenuated impact compared to the flip-flop, reducing the maximal instantaneous loading rate by 19% (p < 0.001). Modifications to the sagittal plane ankle angle, frontal plane motion and characteristics of initial contact observed in barefoot walking occur in flip-flop footwear. The FitFlop may reduce risks traditionally associated with flip-flop footwear by reducing loading rate at heel strike and frontal plane motion at the ankle during stance.

Do Ankle Orthoses Improve Ankle Proprioceptive Thresholds or Unipedal Balance in Older Persons with Peripheral Neuropathy?

PubMed Central

Son, Jaebum; Ashton-Miller, James A.; Richardson, James K.

2010-01-01

Objective To determine whether ankle orthoses that provide medial and lateral support, and have been found to decrease gait variability in older persons with peripheral neuropathy, decrease (improve) frontal plane ankle proprioceptive thresholds or increase unipedal stance time in that same population. Design Observational study in which unipedal stance time was determined with a stopwatch, and frontal plane ankle (inversion and eversion) proprioceptive thresholds were quantified during bipedal stance with and without the ankle orthoses, in 11 older diabetic subjects with peripheral neuropathy (8 men; age 72 ± 7.1 years) using a foot cradle system which presented a series of 100 rotational stimuli. Results The subjects demonstrated no change in combined frontal plane (inversion + eversion) proprioceptive thresholds or unipedal stance time with versus without the orthoses (1.06 ± 0.56 versus 1.13 ± 0.39 degrees, respectively; p = 0.955 and 6.1 ± 6.5 versus 6.2 ± 5.4 seconds, respectively; p = 0.922). Conclusion Ankle orthoses which provide medial-lateral support do not appear to change ankle inversion/eversion proprioceptive thresholds or unipedal stance time in older persons with diabetic peripheral neuropathy. Previously identified improvements in gait variability using orthoses in this population are therefore likely related to an orthotically-induced stiffening of the ankle rather than a change in ankle afferent function. PMID:20407302

Accuracy and Reproducibility Using Patient-Specific Instrumentation in Total Ankle Arthroplasty.

PubMed

Daigre, Justin; Berlet, Gregory; Van Dyke, Bryan; Peterson, Kyle S; Santrock, Robert

2017-04-01

Implant survivorship is dependent on accuracy of implantation and successful soft tissue balancing. System instrumentation for total ankle arthroplasty implantation has a key influence on surgeon accuracy and reproducibility. The purpose of this study was to determine the accuracy and reproducibility of implant position with patient-specific guides for total ankle arthroplasty across multiple surgeons at multiple facilities. This retrospective, multicenter study included 44 patients who received a total ankle implant (INBONE II Total Ankle System; Wright Medical Technology, Memphis, TN) using PROPHECY patient-specific guides from January 2012 to December 2014. Forty-four patients with an average age of 63.0 years underwent total ankle arthroplasty using this preoperative patient-specific system. Preoperative computed tomography (CT) scans were obtained to assess coronal plane deformity, assess mechanical and anatomic alignment, and build patient-specific guides that referenced bony anatomy. The mean preoperative coronal deformity was 4.6 ± 4.6 degrees (range, 14 degrees varus to 17 degrees valgus). The first postoperative weightbearing radiographs were used to measure coronal and sagittal alignment of the implant vs the anatomic axis of the tibia. In 79.5% of patients, the postoperative implant position of the tibia corresponded to the preoperative plan of the tibia within 3 degrees of the intended target, within 4 degrees in 88.6% of patients, and within 5 degrees in 100% of patients. The tibial component coronal size was correctly predicted in 98% of cases, whereas the talar component was correctly predicted in 80% of cases. The use of patient-specific instrumentation for total ankle arthroplasty provided reliable alignment and reproducibility in the clinical situation similar to that shown in cadaveric testing. This study has shown that the preoperative patient-specific instrumentation provided for accuracy and reproducibility of ankle arthroplasty implantation

Sagittal-Plane Knee Moment During Gait and Knee Cartilage Thickness.

PubMed

Schmitz, Randy J; Harrison, David; Wang, Hsin-Min; Shultz, Sandra J

2017-06-02

  Understanding the factors associated with thicker cartilage in a healthy population is important when developing strategies aimed at minimizing the cartilage thinning associated with knee osteoarthritis progression. Thicker articular cartilage is commonly thought to be healthier cartilage, but whether the sagittal-plane biomechanics important to gait are related to cartilage thickness is unknown.   To determine the relationship of a weight-bearing region of the medial femoral condyle's cartilage thickness to sagittal gait biomechanics in healthy individuals.   Descriptive laboratory study.   Laboratory.   Twenty-eight healthy participants (15 women: age = 21.1 ± 2.1 years, height = 1.63 ± 0.07 m, weight = 64.6 ± 9.9 kg; 13 men: age = 22.1 ± 2.9 years, height = 1.79 ± 0.05 m, weight = 75.2 ± 9.6 kg).   Tibiofemoral angle (°) was obtained via goniometric assessment, thickness of the medial femoral condyle cartilage (mm) was obtained via ultrasound imaging, and peak internal knee-extensor moment (% body weight · height) was measured during 10 trials of over-ground walking at a self-selected pace. We used linear regression to examine the extent to which peak internal knee-extensor moment predicted cartilage thickness after accounting for tibiofemoral angle and sex.   Sex and tibiofemoral angle (12.3° ± 3.2°) were entered in the initial step as control factors (R 2 = 0.01, P = .872). In the final step, internal knee-extensor moment (1.5% ± 1.3% body weight · height) was entered, which resulted in greater knee-extensor moment being related to greater cartilage thickness (2.0 ± 0.3 mm; R 2 Δ = 0.31, PΔ = .003).   Individuals who walked with a greater peak internal knee-extensor moment during gait had a cartilage structure that is generally considered beneficial in a healthy population. Our study offers promising findings that a potentially modifiable biomechanical factor is associated with cartilage status in a healthy population

Sagittal-Plane Knee Moment During Gait and Knee Cartilage Thickness

PubMed Central

Harrison, David; Wang, Hsin-Min; Shultz, Sandra J.

2017-01-01

Context:  Understanding the factors associated with thicker cartilage in a healthy population is important when developing strategies aimed at minimizing the cartilage thinning associated with knee osteoarthritis progression. Thicker articular cartilage is commonly thought to be healthier cartilage, but whether the sagittal-plane biomechanics important to gait are related to cartilage thickness is unknown. Objective:  To determine the relationship of a weight-bearing region of the medial femoral condyle's cartilage thickness to sagittal gait biomechanics in healthy individuals. Design:  Descriptive laboratory study. Setting:  Laboratory. Patients or Other Participants:  Twenty-eight healthy participants (15 women: age = 21.1 ± 2.1 years, height = 1.63 ± 0.07 m, weight = 64.6 ± 9.9 kg; 13 men: age = 22.1 ± 2.9 years, height = 1.79 ± 0.05 m, weight = 75.2 ± 9.6 kg). Main Outcome Measure(s):  Tibiofemoral angle (°) was obtained via goniometric assessment, thickness of the medial femoral condyle cartilage (mm) was obtained via ultrasound imaging, and peak internal knee-extensor moment (% body weight · height) was measured during 10 trials of over-ground walking at a self-selected pace. We used linear regression to examine the extent to which peak internal knee-extensor moment predicted cartilage thickness after accounting for tibiofemoral angle and sex. Results:  Sex and tibiofemoral angle (12.3° ± 3.2°) were entered in the initial step as control factors (R2 = 0.01, P = .872). In the final step, internal knee-extensor moment (1.5% ± 1.3% body weight · height) was entered, which resulted in greater knee-extensor moment being related to greater cartilage thickness (2.0 ± 0.3 mm; R2Δ = 0.31, PΔ = .003). Conclusion:  Individuals who walked with a greater peak internal knee-extensor moment during gait had a cartilage structure that is generally considered beneficial in a healthy population. Our study offers promising findings that a

Lower Extremity Biomechanics in Athletes With Ankle Instability After a 6-Week Integrated Training Program

PubMed Central

Huang, Pi-Yin; Chen, Wen-Ling; Lin, Cheng-Feng; Lee, Heng-Ju

2014-01-01

Context: Plyometric exercise has been recommended to prevent lower limb injury, but its feasibility in and effects on those with functional ankle instability (FAI) are unclear. Objective: To investigate the effect of integrated plyometric and balance training in participants with FAI during a single-legged drop landing and single-legged standing position. Design: Randomized controlled clinical trial. Setting: University motion-analysis laboratory. Patients or Other Participants: Thirty athletes with FAI were divided into 3 groups: plyometric group (8 men, 2 women, age = 23.20 ± 2.82 years; 10 unstable ankles), plyometric-balance (integrated)–training group (8 men, 2 women, age = 23.80 ± 4.13 years; 10 unstable ankles), and control group (7 men, 3 women, age = 23.50 ± 3.00 years; 10 unstable ankles). Intervention(s): A 6-week plyometric-training program versus a 6-week integrated-training program. Main Outcome Measure(s): Postural sway during single-legged standing with eyes open and closed was measured before and after training. Kinematic data were recorded during medial and lateral single-legged drop landings after a 5-second single-legged stance. Results: Reduced postural sway in the medial-lateral direction and reduced sway area occurred in the plyometric- and integrated-training groups. Generally, the plyometric training and integrated training increased the maximum angles at the hip and knee in the sagittal plane, reduced the maximum angles at the hip and ankle in the frontal and transverse planes in the lateral drop landing, and reduced the time to stabilization for knee flexion in the medial drop landing. Conclusions: After 6 weeks of plyometric training or integrated training, individuals with FAI used a softer landing strategy during drop landings and decreased their postural sway during the single-legged stance. Plyometric training improved static and dynamic postural control and should be incorporated into rehabilitation programs for those with FAI

Two level pedicle substraction osteotomies for the treatment of severe fixed sagittal plane deformity: computer software-assisted preoperative planning and assessing.

PubMed

Atici, Yunus; Akman, Yunus Emre; Balioglu, Mehmet Bulent; Kargin, Deniz; Kaygusuz, Mehmet Akif

2016-08-01

To evaluate the efficacy of two level pedicle substraction osteotomies (PSOs) planned preoperatively with a computer software, in the patients with severe fixed sagittal plane deformities. In the literature, there are studies indicating that two level PSOs may be required in severe cases. However, the results of two level PSOs preoperatively planned with computer software-assistance have not yet been reported in the English literature. Severe fixed sagittal plane deformities of 11 patients are described. Preoperative surgical planning was done with the aid of a computer software. Two level PSOs were indicated after the process. After the application of the indicated surgical technique, clinical and radiological results were evaluated in the preoperative, the early postoperative periods and during the last follow-up. The mean sagittal vertical axis was found as 190.5 (range 161-220) mm in the preoperative period, 23.5 (range -27 to 61) mm in the early postoperative period (P < 0.001) (87.7 % correction) and 34.5 (range -3 to 55) mm during the last follow-up (P < 0.001). The mean pelvic tilt (PT) significantly decreased from 38.3° (range 21°-63°) preoperatively to 23.8° (range 18°-42°) postoperatively (P = 0.008) and to 27.5° (range 17°-42°) during the last follow-up (P = 0.042). The mean lumbar lordosis (LL) was 2.8° (range -29° to 20°) preoperatively, -35.6° (range -54° to 23°) early postoperatively (P < 0.001) and -33.6° (range -52° to 20°) during the last follow-up (P < 0.001). The average amount of bleeding was 5345 (range 2600-7415) ml. Although a statistically significant correction was obtained, the mean PT and PI-LL value could not be restored in physiological limits during the last follow-up. Thus, two level PSOs performed after computer software (surgimap) assisted preoperative planning failed to correct severe fixed sagittal plane deformities. Besides, this procedure is of possible risks for major complications such as a

Assessing the Relative Contributions of Active Ankle and Knee Assistance to the Walking Mechanics of Transfemoral Amputees Using a Powered Prosthesis

PubMed Central

Simon, Ann M.; Hargrove, Levi J.

2016-01-01

Powered knee-ankle prostheses are capable of providing net-positive mechanical energy to amputees. Yet, there are limitless ways to deliver this energy throughout the gait cycle. It remains largely unknown how different combinations of active knee and ankle assistance affect the walking mechanics of transfemoral amputees. This study assessed the relative contributions of stance phase knee swing initiation, increasing ankle stiffness and powered plantarflexion as three unilateral transfemoral amputees walked overground at their self-selected walking speed. Five combinations of knee and ankle conditions were evaluated regarding the kinematics and kinetics of the amputated and intact legs using repeated measures analyses of variance. We found eliminating active knee swing initiation or powered plantarflexion was linked to increased compensations of the ipsilateral hip joint during the subsequent swing phase. The elimination of knee swing initiation or powered plantarflexion also led to reduced braking ground reaction forces of the amputated and intact legs, and influenced both sagittal and frontal plane loading of the intact knee joint. Gradually increasing prosthetic ankle stiffness influenced the shape of the prosthetic ankle plantarflexion moment, more closely mirroring the intact ankle moment. Increasing ankle stiffness also corresponded to increased prosthetic ankle power generation (despite a similar maximum stiffness value across conditions) and increased braking ground reaction forces of the amputated leg. These findings further our understanding of how to deliver assistance with powered knee-ankle prostheses and the compensations that occur when specific aspects of assistance are added/removed. PMID:26807889

Embracing additive manufacture: implications for foot and ankle orthosis design

PubMed Central

2012-01-01

Background The design of foot and ankle orthoses is currently limited by the methods used to fabricate the devices, particularly in terms of geometric freedom and potential to include innovative new features. Additive manufacturing (AM) technologies, where objects are constructed via a series of sub-millimetre layers of a substrate material, may present the opportunity to overcome these limitations and allow novel devices to be produced that are highly personalised for the individual, both in terms of fit and functionality. Two novel devices, a foot orthosis (FO) designed to include adjustable elements to relieve pressure at the metatarsal heads, and an ankle foot orthosis (AFO) designed to have adjustable stiffness levels in the sagittal plane, were developed and fabricated using AM. The devices were then tested on a healthy participant to determine if the intended biomechanical modes of action were achieved. Results The adjustable, pressure relieving FO was found to be able to significantly reduce pressure under the targeted metatarsal heads. The AFO was shown to have distinct effects on ankle kinematics which could be varied by adjusting the stiffness level of the device. Conclusions The results presented here demonstrate the potential design freedom made available by AM, and suggest that it may allow novel personalised orthotic devices to be produced which are beyond the current state of the art. PMID:22642941

Transverse forces versus modified ashworth scale for upper limb flexion/extension in para-sagittal plane.

PubMed

Seth, Nitin; Johnson, Denise; Abdullah, Hussein A

2017-07-01

Spasticity is a common impairment following an upper motor neuron lesion in conditions such as stroke and brain injury. A clinical issue is how to best quantify and measure spasticity. Recently, research has been performed to develop new methods of spasticity quantification using various systems. This paper follows up on previous work taking a closer look at the role of transversal forces obtained via rehabilitation robot for motions in the para-sagittal plane. Results from 45 healthy individuals and 40 individuals with acquired brain injury demonstrate that although the passive upper motions are vertical, horizontal forces into and away from the individual's body demonstrate a relationship with the Modified Ashworth Scale. This finding leads the way to new avenues of spasticity quantification and monitoring.

Influence of time restriction, 20 minutes and 94.6 months, of visual information on angular displacement during the sit-to-stand (STS) task in three planes.

PubMed

Aylar, Mozhgan Faraji; Firouzi, Faramarz; Araghi, Mandana Rahnama

2016-12-01

[Purpose] The purpose of this investigation was to assess whether or not restriction of visual information influences the kinematics of sit-to-stand (STS) performance in children. [Subjects and Methods] Five girls with congenital blindness (CB) and ten healthy girls with no visual impairments were randomly selected. The girls with congenital blindness were placed in one group and the ten girls with no visual impairments were divided into two groups of five, control and treatment groups. The participants in the treatment group were asked to close their eyes (EC) for 20 minutes before the STS test, whereas those in the control group kept their eyes open (EO). The performance of the participants in all three groups was measured using a motion capture system and two force plates. [Results] The results show that the constraint duration of visual sensory information affected the range of motion (ROM), the excursion of the dominant side ankle, and the ROM of the dominant side knee in the EC group. However, only ankle excursion on the non-dominant side was affected in the CB group, and this was only observed in the sagittal plane. [Conclusion] These results indicate that visual memory does not affect the joint angles in the frontal and transverse planes. Moreover, all of the participants could perform the STS transition without falling, indicating; the participants performed the STS maneuver correctly in all planes except the sagittal one.

Ankle and hip postural strategies defined by joint torques

NASA Technical Reports Server (NTRS)

Runge, C. F.; Shupert, C. L.; Horak, F. B.; Zajac, F. E.; Peterson, B. W. (Principal Investigator)

1999-01-01

Previous studies have identified two discrete strategies for the control of posture in the sagittal plane based on EMG activations, body kinematics, and ground reaction forces. The ankle strategy was characterized by body sway resembling a single-segment-inverted pendulum and was elicited on flat support surfaces. In contrast, the hip strategy was characterized by body sway resembling a double-segment inverted pendulum divided at the hip and was elicited on short or compliant support surfaces. However, biomechanical optimization models have suggested that hip strategy should be observed in response to fast translations on a flat surface also, provided the feet are constrained to remain in contact with the floor and the knee is constrained to remain straight. The purpose of this study was to examine the experimental evidence for hip strategy in postural responses to backward translations of a flat support surface and to determine whether analyses of joint torques would provide evidence for two separate postural strategies. Normal subjects standing on a flat support surface were translated backward with a range of velocities from fast (55 cm/s) to slow (5 cm/s). EMG activations and joint kinematics showed pattern changes consistent with previous experimental descriptions of mixed hip and ankle strategy with increasing platform velocity. Joint torque analyses revealed the addition of a hip flexor torque to the ankle plantarflexor torque during fast translations. This finding indicates the addition of hip strategy to ankle strategy to produce a continuum of postural responses. Hip torque without accompanying ankle torque (pure hip strategy) was not observed. Although postural control strategies have previously been defined by how the body moves, we conclude that joint torques, which indicate how body movements are produced, are useful in defining postural control strategies. These results also illustrate how the biomechanics of the body can transform discrete control

Male and female runners demonstrate different sagittal plane mechanics as a function of static hamstring flexibility.

PubMed

Williams, D S Blaise; Welch, Lee M

2015-01-01

Injuries to runners are common. However, there are many potential contributing factors to injury. While lack of flexibility alone is commonly related to injury, there are clear differences in hamstring flexibility between males and females. To compare the effect of static hamstring length on sagittal plane mechanics between male and female runners. Forty subjects (30.0±6.4 years) participated and were placed in one of 4 groups: flexible males (n=10), inflexible males (n=10), flexible females (n=10), and inflexible females (n=10). All subjects were free of injury at the time of data collection. Three-dimensional kinematics and kinetics were collected while subjects ran over ground across 2 force platforms. Sagittal plane joint angles and moments were calculated at the knee and hip and compared with a 2-way (sex X flexibility) ANOVA (α=0.05). Males exhibited greater peak knee extension moment than females (M=2.80±0.47, F=2.48±0.52 Nm/kg*m, p=0.05) and inflexible runners exhibited greater peak knee extension moment than flexible runners (In=2.83±0.56, Fl=2.44±0.51 Nm/kg*m, p=0.01). For hip flexion at initial contact, a significant interaction existed (p<0.05). Flexible females (36.7±7.4º) exhibited more hip flexion than inflexible females (27.9±4.6º, p<0.01) and flexible males (30.1±9.5º, p<0.05). No differences existed for knee angle at initial contact, peak knee angle, peak hip angle, or peak hip moment. Hamstring flexibility results in different mechanical profiles in males and females. Flexibility in the hamstrings may result in decreased moments via active or passive tension. These differences may have implications for performance and injury in flexible female runners.

Male and female runners demonstrate different sagittal plane mechanics as a function of static hamstring flexibility

PubMed Central

Williams III, D. S. Blaise; Welch, Lee M.

2015-01-01

ABSTRACT Background: Injuries to runners are common. However, there are many potential contributing factors to injury. While lack of flexibility alone is commonly related to injury, there are clear differences in hamstring flexibility between males and females. Objective: To compare the effect of static hamstring length on sagittal plane mechanics between male and female runners. Method: Forty subjects (30.0±6.4 years) participated and were placed in one of 4 groups: flexible males (n=10), inflexible males (n=10), flexible females (n=10), and inflexible females (n=10). All subjects were free of injury at the time of data collection. Three-dimensional kinematics and kinetics were collected while subjects ran over ground across 2 force platforms. Sagittal plane joint angles and moments were calculated at the knee and hip and compared with a 2-way (sex X flexibility) ANOVA (α=0.05). Results: Males exhibited greater peak knee extension moment than females (M=2.80±0.47, F=2.48±0.52 Nm/kg*m, p=0.05) and inflexible runners exhibited greater peak knee extension moment than flexible runners (In=2.83±0.56, Fl=2.44±0.51 Nm/kg*m, p=0.01). For hip flexion at initial contact, a significant interaction existed (p<0.05). Flexible females (36.7±7.4º) exhibited more hip flexion than inflexible females (27.9±4.6º, p<0.01) and flexible males (30.1±9.5º, p<0.05). No differences existed for knee angle at initial contact, peak knee angle, peak hip angle, or peak hip moment. Conclusion: Hamstring flexibility results in different mechanical profiles in males and females. Flexibility in the hamstrings may result in decreased moments via active or passive tension. These differences may have implications for performance and injury in flexible female runners. PMID:26537812

Foot and Ankle Kinematics During Descent From Varying Step Heights.

PubMed

Gerstle, Emily E; O'Connor, Kristian; Keenan, Kevin G; Cobb, Stephen C

2017-12-01

In the general population, one-third of incidences during step negotiation occur during the transition to level walking. Furthermore, falls during curb negotiation are a common cause of injury in older adults. Distal foot kinematics may be an important factor in determining injury risk associated with transition step negotiation. The purpose of this study was to identify foot and ankle kinematics of uninjured individuals during descent from varying step heights. A 7-segment foot model was used to quantify kinematics as participants walked on a level walkway, stepped down a single step (heights: 5 cm, 15 cm, 25 cm), and continued walking. As step height increased, landing strategy transitioned from the rearfoot to the forefoot, and the rearfoot, lateral and medial midfoot, and medial forefoot became more plantar flexed. During weight acceptance, sagittal plane range of motion of the rearfoot, lateral midfoot, and medial and lateral forefoot increased as step height increased. The changes in landing strategy and distal foot function suggest a less stable ankle position at initial contact and increased demand on the distal foot at initial contact and through the weight acceptance phase of transition step negotiation as step height increases.

Effect of kinesiotaping, non-elastic taping and bracing on segmental foot kinematics during drop landing in healthy subjects and subjects with chronic ankle instability.

PubMed

Kuni, B; Mussler, J; Kalkum, E; Schmitt, H; Wolf, S I

2016-09-01

To evaluate the effects of kinesiotape, non-elastic tape, and soft brace on segmental foot kinematics during drop landing in subjects with chronic ankle instability and healthy subjects. Controlled study with repeated measurements. Three-dimensional motion analysis laboratory. Twenty participants with chronic ankle instability and 20 healthy subjects. The subjects performed drop landings with 17 retroreflective markers on the foot and lower leg in four conditions: barefoot, with kinesiotape, with non-elastic tape and with a soft brace. Ranges of motion of foot segments using a foot measurement method. In participants with chronic ankle instability, midfoot movement in the frontal plane (inclination of the medial arch) was reduced significantly by non-elastic taping, but kinesiotaping and bracing had no effect. In healthy subjects, both non-elastic taping and bracing reduced that movement. In both groups, non-elastic taping and bracing reduced rearfoot excursion in inversion/eversion significantly, which indicates a stabilisation effect. No such effect was found with kinesiotaping. All three methods reduced maximum plantar flexion significantly. Non-elastic taping stabilised the midfoot best in patients with chronic ankle instability, while kinesiotaping did not influence foot kinematics other than to stabilise the rearfoot in the sagittal plane. ClinicalTrials.gov NCT01810471. Copyright © 2015 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Grizzly bear (Ursus arctos horribilis) locomotion: forelimb joint mechanics across speed in the sagittal and frontal planes.

PubMed

Shine, Catherine L; Robbins, Charles T; Nelson, O Lynne; McGowan, Craig P

2017-04-01

The majority of terrestrial locomotion studies have focused on parasagittal motion and paid less attention to forces or movement in the frontal plane. Our previous research has shown that grizzly bears produce higher medial ground reaction forces (lateral pushing from the animal) than would be expected for an upright mammal, suggesting frontal plane movement may be an important aspect of their locomotion. To examine this, we conducted an inverse dynamics analysis in the sagittal and frontal planes, using ground reaction forces and position data from three high-speed cameras of four adult female grizzly bears. Over the speed range collected, the bears used walks, running walks and canters. The scapulohumeral joint, wrist and the limb overall absorb energy (average total net work of the forelimb joints, -0.97 W kg -1 ). The scapulohumeral joint, elbow and total net work of the forelimb joints have negative relationships with speed, resulting in more energy absorbed by the forelimb at higher speeds (running walks and canters). The net joint moment and power curves maintain similar patterns across speed as in previously studied species, suggesting grizzly bears maintain similar joint dynamics to other mammalian quadrupeds. There is no significant relationship with net work and speed at any joint in the frontal plane. The total net work of the forelimb joints in the frontal plane was not significantly different from zero, suggesting that, despite the high medial ground reaction forces, the forelimb acts as a strut in that plane. © 2017. Published by The Company of Biologists Ltd.

Sagittal plane analysis of the spine and pelvis in degenerative lumbar scoliosis.

PubMed

Han, Fei; Weishi, Li; Zhuoran, Sun; Qingwei, Ma; Zhongqiang, Chen

2017-01-01

Previous studies have reported the normative values of pelvic sagittal parameters, but no study has analyzed the sagittal spino-pelvic alignment in degenerative lumbar scoliosis (DLS) and its role in the pathogenesis. Retrospective analysis was applied to 104 patients with DLS, together with 100 cases of asymptomatic young adults as a control group and another control group consisting of 145 cases with cervical spondylosis. The coronal and sagittal parameters were measured on the anteroposterior and lateral radiograph of the whole spine in the DLS group as well as in the two control groups. Statistical analysis showed that the DLS group had a higher pelvic incidence (PI) value (50.5° ± 10.2°), than the normal control group (with PI 47.2° ± 8.8°) and the cervical spondylosis group (46.9° ± 9.1°). In DLS group, there were 38 cases (36.5%) complicated with degenerative lumbar spondylolisthesis, who had higher PI values than patients without it. Besides, the lumbar lordosis (LL) and sacral slope (SS) of DLS group were lower; the scoliosis Cobb's angle was correlated with pelvic tilt (PT); thoracic kyphosis was correlated with LL, SS, and PT; and LL was correlated with other sagittal parameters. Patients with DLS may have a higher PI, which may impact the pathogenesis of DLS. A high PI value is probably associated with the high prevalence of degenerative lumbar spondylolisthesis among DLS patients. In DLS patients, the lumbar spine maintains the ability of regulating the sagittal balance, and the regulation depends more on thoracic curve.

Training intensity and sagittal curvature of the spine in male and female artistic gymnasts.

PubMed

Sanz-Mengibar, Jose M; Sainz-de-Baranda, Pilar; Santonja-Medina, Fernando

2018-04-01

Specific adaptations of the spine in the sagittal plane have been described according to different sports disciplines. The goal of this study was to describe the integrative diagnosis of the sagittal morphotype of the spine in male and female artistic gymnasts. Forty-eight gymnasts were measured with an inclinometer. Thoracic and lumbar curves were quantified in standing position, in Sit and Reach and Slump Sitting in order to assess the sagittal spine posture and analyze if adaptations were related to training intensity. Correlation values of the sagittal plane spine measurements showed significantly increased thoracic kyphosis in men (-0.445, P<0.001). No significant correlations have been found between training hours per year or training volume and any measurements of the spine on the sagittal plane. When data from the two sitting tests were integrated, 62.5% of gymnasts had a functional thoracic kyphosis and 39.6% had lumbar kyphotic attitude. Our hypothesis has only been partially confirmed, because training intensity did not influence the sagittal curvatures in artistic gymnastics; however, this sport seems to cause specific adaptations in postural hypolordosis, functional thoracic kyphosis and lumbar kyphotic attitude during sitting and trunk flexion. The implications of the functional adaptations observed in our results may require a preventive intervention in male and female artistic gymnasts can be assessed with the integrative diagnosis of the sagittal morphotype of the spine.

Recovery From a First-Time Lateral Ankle Sprain and the Predictors of Chronic Ankle Instability: A Prospective Cohort Analysis.

PubMed

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

2016-04-01

Impairments in motor control may predicate the paradigm of chronic ankle instability (CAI) that can develop in the year after an acute lateral ankle sprain (LAS) injury. No prospective analysis is currently available identifying the mechanisms by which these impairments develop and contribute to long-term outcome after LAS. To identify the motor control deficits predicating CAI outcome after a first-time LAS injury. Cohort study (diagnosis); Level of evidence, 2. Eighty-two individuals were recruited after sustaining a first-time LAS injury. Several biomechanical analyses were performed for these individuals, who completed 5 movement tasks at 3 time points: (1) 2 weeks, (2) 6 months, and (3) 12 months after LAS occurrence. A logistic regression analysis of several "salient" biomechanical parameters identified from the movement tasks, in addition to scores from the Cumberland Ankle Instability Tool and the Foot and Ankle Ability Measure (FAAM) recorded at the 2-week and 6-month time points, were used as predictors of 12-month outcome. At the 2-week time point, an inability to complete 2 of the movement tasks (a single-leg drop landing and a drop vertical jump) was predictive of CAI outcome and correctly classified 67.6% of cases (sensitivity, 83%; specificity, 55%; P = .004). At the 6-month time point, several deficits exhibited by the CAI group during 1 of the movement tasks (reach distances and sagittal plane joint positions at the hip, knee and ankle during the posterior reach directions of the Star Excursion Balance Test) and their scores on the activities of daily living subscale of the FAAM were predictive of outcome and correctly classified 84.8% of cases (sensitivity, 75%; specificity, 91%; P < .001). An inability to complete jumping and landing tasks within 2 weeks of a first-time LAS and poorer dynamic postural control and lower self-reported function 6 months after a first-time LAS were predictive of eventual CAI outcome. © 2016 The Author(s).

Does Knee Osteoarthritis Differentially Modulate Proprioceptive Acuity in the Frontal and Sagittal Planes of the Knee?

PubMed Central

Cammarata, Martha L; Schnitzer, Thomas J; Dhaher, Yasin Y

2012-01-01

Objective Impaired proprioception may alter joint loading and contribute to the progression of knee osteoarthritis (OA). Though frontal plane loading at the knee contributes to OA, proprioception and its modulation with OA in this direction have not been examined. The aim of this study was to assess knee proprioceptive acuity in the frontal and sagittal planes in knee OA and healthy participants. We hypothesized that proprioceptive acuity will be decreased in the OA population in both planes of movement. Methods Thirteen persons with knee OA and fourteen healthy age-matched subjects participated. Proprioceptive acuity was assessed in varus, valgus, flexion, and extension using the threshold to detection of passive movement (TDPM). Repeated measures analysis of variance was used to assess differences in TDPM between subject groups and across movement directions. Linear regression analyses were performed to assess the correlation of TDPM between and within planes of movement. Results TDPM was found to be significantly higher (P<0.05), in the knee OA group compared to the control group for all directions tested, indicating reduced proprioceptive acuity. Differences in TDPM between groups were consistent across all movement directions, with mean difference (95% CI) for valgus: 0.94° (0.20°, 1.65°), varus: 0.92° (0.18°, 1.68°), extension: 0.93° (0.19°, 1.66°), and flexion: 1.11° (0.38°, 1.85°). TDPM measures across planes of movement were only weakly correlated, especially in the OA group. Conclusions Consistent differences in TDPM between the OA and control groups across all movement directions suggest a global, not direction-specific, reduction in sensation in knee OA patients. PMID:21547895

Making planes plain.

PubMed

O'Rahilly, R

1997-01-01

The major anatomical planes (horizontal, coronal, and sagittal, including the median plane) are discussed from a historical perspective, and their correct usage is clarified. Unofficial and unnecessary terms to be avoided (for reasons explained) include midsagittal, parasagittal, and midline.

Assessment of female ballet dancers' ankles in the en pointe position using high field strength magnetic resonance imaging.

PubMed

Russell, Jeffrey A; Yoshioka, Hiroshi

2016-08-01

The en pointe position of the ankle in ballet is extreme. Previously, magnetic resonance imaging (MRI) of ballet dancers' ankles en pointe was confined to a low field, open MR device. To develop a reproducible ankle MRI protocol for ballet dancers en pointe and to assess the positions of the key structures in the dancers ankles. Six female ballet dancers participated; each was randomly assigned to stand en pointe while one of her feet and ankles was splinted with wooden rods affixed with straps or to begin with the ankle in neutral position. She lay in an MR scanner with the ankle inside a knee coil for en pointe imaging and inside an ankle/foot coil for neutral position imaging. Proton density weighted images with and without fat suppression and 3D water excitation gradient recalled echo images were obtained en pointe and in neutral position in sagittal, axial, and coronal planes. We compared the bones, cartilage, and soft tissues within and between positions. No difficulties using the protocol were encountered. En pointe the posterior articular surface of the tibial plafond was incongruent with the talar dome and rested on the posterior talus. The posterior edge of the plafond impinged Kager's fat pad. All participants exhibited one or more small ganglion cysts about the ankle and proximal foot, as well as fluid accumulation in the flexor and fibularis tendon sheaths. Our MRI protocol allows assessment of female ballet dancers' ankles in the extreme plantar flexion position in which the dancers perform. We consistently noted incongruence of the talocrural joint and convergence of the tibia, talus, and calcaneus posteriorly. This protocol may be useful for clinicians who evaluate dancers. © The Foundation Acta Radiologica 2015.

Comparison of the trunk-pelvis and lower extremities sagittal plane inter-segmental coordination and variability during walking in persons with and without chronic low back pain.

PubMed

Ebrahimi, Samaneh; Kamali, Fahimeh; Razeghi, Mohsen; Haghpanah, Seyyed Arash

2017-04-01

Inter-segmental coordination can be influenced by chronic low back pain (CLBP). The sagittal plane lower extremities inter-segmental coordination pattern and variability, in conjunction with the pelvis and trunk, were assessed in subjects with and without non-specific CLBP during free-speed walking. Kinematic data were collected from 10 non-specific CLBP and 10 non-CLBP control volunteers while the subjects were walking at their preferred speed. Sagittal plane time-normalized segmental angles and velocities were used to calculate continuous relative phase for each data point. Mean absolute relative phase (MARP) and deviation phase (DP) were derived to quantify the trunk-pelvis and bilateral pelvis-thigh, thigh-shank and shank-foot coordination pattern and variability over the stance and swing phases of gait. Mann-Whitney U test was employed to compare the means of DP and MARP values between two groups (same side comparison). Statistical analysis revealed more in-phase/less variable trunk-pelvis coordination in the CLBP group (P<0.05). CLBP group demonstrated less variable right or left pelvis-thigh coordination pattern (P<0.05). Moreover, the left thigh-shank and left shank-foot MARP values in the CLBP group, were more in-phase than left MARP values in the non-CLBP control group during the swing phase (P<0.05). In conclusion, the sagittal plane lower extremities, pelvis and trunk coordination pattern and variability could be generally affected by CLBP during walking. These changes can be possible compensatory strategies of the motor control system which can be considered in the CLBP subjects. Copyright © 2017 Elsevier B.V. All rights reserved.

Measurement and Finite Element Model Validation of Immature Porcine Brain-Skull Displacement during Rapid Sagittal Head Rotations.

PubMed

Pasquesi, Stephanie A; Margulies, Susan S

2018-01-01

Computational models are valuable tools for studying tissue-level mechanisms of traumatic brain injury, but to produce more accurate estimates of tissue deformation, these models must be validated against experimental data. In this study, we present in situ measurements of brain-skull displacement in the neonatal piglet head ( n  = 3) at the sagittal midline during six rapid non-impact rotations (two rotations per specimen) with peak angular velocities averaging 51.7 ± 1.4 rad/s. Marks on the sagittally cut brain and skull/rigid potting surfaces were tracked, and peak values of relative brain-skull displacement were extracted and found to be significantly less than values extracted from a previous axial plane model. In a finite element model of the sagittally transected neonatal porcine head, the brain-skull boundary condition was matched to the measured physical experiment data. Despite smaller sagittal plane displacements at the brain-skull boundary, the corresponding finite element boundary condition optimized for sagittal plane rotations is far less stiff than its axial counterpart, likely due to the prominent role of the boundary geometry in restricting interface movement. Finally, bridging veins were included in the finite element model. Varying the bridging vein mechanical behavior over a previously reported range had no influence on the brain-skull boundary displacements. This direction-specific sagittal plane boundary condition can be employed in finite element models of rapid sagittal head rotations.

Measurement and Finite Element Model Validation of Immature Porcine Brain–Skull Displacement during Rapid Sagittal Head Rotations

PubMed Central

Pasquesi, Stephanie A.; Margulies, Susan S.

2018-01-01

Computational models are valuable tools for studying tissue-level mechanisms of traumatic brain injury, but to produce more accurate estimates of tissue deformation, these models must be validated against experimental data. In this study, we present in situ measurements of brain–skull displacement in the neonatal piglet head (n = 3) at the sagittal midline during six rapid non-impact rotations (two rotations per specimen) with peak angular velocities averaging 51.7 ± 1.4 rad/s. Marks on the sagittally cut brain and skull/rigid potting surfaces were tracked, and peak values of relative brain–skull displacement were extracted and found to be significantly less than values extracted from a previous axial plane model. In a finite element model of the sagittally transected neonatal porcine head, the brain–skull boundary condition was matched to the measured physical experiment data. Despite smaller sagittal plane displacements at the brain–skull boundary, the corresponding finite element boundary condition optimized for sagittal plane rotations is far less stiff than its axial counterpart, likely due to the prominent role of the boundary geometry in restricting interface movement. Finally, bridging veins were included in the finite element model. Varying the bridging vein mechanical behavior over a previously reported range had no influence on the brain–skull boundary displacements. This direction-specific sagittal plane boundary condition can be employed in finite element models of rapid sagittal head rotations. PMID:29515995

Measures of functional limitation as predictors of disablement in athletes with acute ankle sprains.

PubMed

Wilson, R W; Gansneder, B M

2000-09-01

Prospective multivariate design. To determine the usefulness of activity scores, self-reported athletic ability, and selected measures of physical impairment as predictors of disability duration in athletes with ankle inversion sprains. Although several measures of physical impairment and functional limitation are used to assess the consequences of injury following ankle sprain, researchers have yet to establish which measures provide the most accurate predictions of disability duration. Physical impairment, activity limitation, and disability duration were measured in 21 athletes (13 men and 8 women; mean age = 20.3 +/- 1.7 years) with acute ankle sprains. Sagittal plane ankle range of motion and volumetric displacement were used as impairment indicators. Weight-bearing activity scores (task completion count) and self-reported athletic ability (visual analog scale) were used to represent functional limitation. Elapsed time from injury to return to full athletic participation was used as the criterion measure of disability duration. The impairment measures accounted for approximately one-third of the variance in disability duration (R2 = 0.342). Adding the activity limitation measures to the regression model improved predictions of disability duration (R2 = 0.670; stepwise R2 change = 0.328). The measures of activity limitation alone, however, accounted for approximately 67% (R2 = 0.665) of the total variance in the number of days lost due to injury. Measures of activity limitation were the strongest predictors of elapsed time from injury to return to full athletic participation.

Rigid Ankle Foot Orthosis Deteriorates Mediolateral Balance Control and Vertical Braking during Gait Initiation

PubMed Central

Delafontaine, Arnaud; Gagey, Olivier; Colnaghi, Silvia; Do, Manh-Cuong; Honeine, Jean-Louis

2017-01-01

Rigid ankle-foot orthoses (AFO) are commonly used for impeding foot drop during the swing phase of gait. They also reduce pain and improve gait kinematics in patients with weakness or loss of integrity of ankle-foot complex structures due to various pathological conditions. However, this comes at the price of constraining ankle joint mobility, which might affect propulsive force generation and balance control. The present study examined the effects of wearing an AFO on biomechanical variables and electromyographic activity of tibialis anterior (TA) and soleus muscles during gait initiation (GI). Nineteen healthy adults participated in the study. They initiated gait at a self-paced speed with no ankle constraint as well as wearing an AFO on the stance leg, or bilaterally. Constraining the stance leg ankle decreased TA activity ipsilaterally during the anticipatory postural adjustment (APA) of GI, and ipsilateral soleus activity during step execution. In the sagittal plane, the decrease in the stance leg TA activity reduced the backward displacement of the center of pressure (CoP) resulting in a reduction of the forward velocity of the center of mass (CoM) measured at foot contact (FC). In the frontal plane, wearing the AFO reduced the displacement of the CoP in the direction of the swing leg during the APA phase. The mediolateral velocity of the CoM increased during single-stance prompting a larger step width to recover balance. During step execution, the CoM vertical downward velocity is normally reduced in order to lessen the impact of the swing leg with the floor and facilitates the rise of the CoM that occurs during the subsequent double-support phase. The reduction in stance leg soleus activity caused by constraining the ankle weakened the vertical braking of the CoM during step execution. This caused the absolute instantaneous vertical velocity of the CoM at FC to be greater in the constrained conditions with respect to the control condition. From a

Single-leg drop landing motor control strategies following acute ankle sprain injury.

PubMed

Doherty, C; Bleakley, C; Hertel, J; Caulfield, B; Ryan, J; Delahunt, E

2015-08-01

No research currently exists investigating the effect of acute injury on single-limb landing strategies. The aim of the current study was to analyze the coordination strategies of participants in the acute phase of lateral ankle sprain (LAS) injury. Thirty-seven participants with acute, first-time LAS and 19 uninjured participants completed a single-leg drop landing task on both limbs. Three-dimensional kinematic (angular displacement) and sagittal plane kinetic (moment-of-force) data were acquired for the joints of the lower extremity from 200 ms pre-initial contact (IC) to 200 ms post-IC. The peak magnitude of the vertical component of the ground reaction force (GRF) was also computed. Injured participants displayed a bilateral increase in hip flexion, with altered transverse plane kinematic profiles at the knee and ankle for both limbs (P < 0.05). This coincided with a reduction in the net-supporting flexor moment of the lower extremity (P < 0.05) and magnitude of the peak vertical GRF for the injured limb (21.82 ± 2.44 N/kg vs 24.09 ± 2.77 N/kg; P = 0.013) in injured participants compared to control participants. These results demonstrate that compensatory movement strategies are utilized by participants with acute LAS to successfully reduce the impact forces of landing. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Modelling of human walking to optimise the function of ankle-foot orthosis in Guillan-Barré patients with drop foot.

PubMed

Jamshidi, N; Rostami, M; Najarian, S; Menhaj, M B; Saadatnia, M; Firooz, S

2009-04-01

This paper deals with the dynamic modelling of human walking. The main focus of this research was to optimise the function of the orthosis in patients with neuropathic feet, based on the kinematics data from different categories of neuropathic patients. The patient's body on the sagittal plane was modelled for calculating the torques generated in joints. The kinematics data required for mathematical modelling of the patients were obtained from the films of patients captured by high speed camera, and then the films were analysed through a motion analysis software. An inverse dynamic model was used for estimating the spring coefficient. In our dynamic model, the role of muscles was substituted by adding a spring-damper between the shank and ankle that could compensate for their weakness by designing ankle-foot orthoses based on the kinematics data obtained from the patients. The torque generated in the ankle was varied by changing the spring constant. Therefore, it was possible to decrease the torque generated in muscles which could lead to the design of more comfortable and efficient orthoses. In this research, unlike previous research activities, instead of studying the abnormal gait or modelling the ankle-foot orthosis separately, the function of the ankle-foot orthosis on the abnormal gait has been quantitatively improved through a correction of the torque.

The use of the T1 sagittal angle in predicting overall sagittal balance of the spine.

PubMed

Knott, Patrick T; Mardjetko, Steven M; Techy, Fernando

2010-11-01

A balanced sagittal alignment of the spine has been shown to strongly correlate with less pain, less disability, and greater health status scores. To restore proper sagittal balance, one must assess the position of the occiput relative to the sacrum. The assessment of spinal balance preoperatively can be challenging, whereas predicting postoperative balance is even more difficult. This study was designed to evaluate and quantify multiple factors that influence sagittal balance. Retrospective analysis of existing spinal radiographs. A retrospective review of 52 adult spine patient records was performed. All patients had full-column digital radiographs that showed all the important skeletal landmarks necessary for accurate measurement. The average age of the patient was 53 years. Both genders were equally represented. The radiographs were measured using standard techniques to obtain the following parameters: scoliosis in the coronal plane; lordosis or kyphosis of the cervical, thoracic, and lumbar spine; the T1 sagittal angle (angle between a horizontal line and the superior end plate of T1); the angle of the dens in the sagittal plane; the angle of the dens in relation to the occiput; the sacral slope; the pelvic incidence; the femoral-sacral angle; and finally, the sagittal vertical axis (SVA) measured from both the dens of C2 and from C7. It was found that the SVA when measured from the dens was on average 16 mm farther forward than the SVA measured from C7 (p<.0001). The dens plumb line (SVA(dens)) was then used in the study. An analysis was done to examine the relationship between SVA(dens) and each of the other measurements. The T1 sagittal angle was found to have a moderate positive correlation (r=0.65) with SVA(dens), p<.0001, indicating that the amount of sagittal T1 tilt can be used as a good predictor of overall sagittal balance. When examining the other variables, it was found that cervical lordosis had a weak correlation (r=0.37) with SVA(dens) that was

Peak Lower Extremity Landing Kinematics in Dancers and Nondancers.

PubMed

Hansberger, Bethany L; Acocello, Shellie; Slater, Lindsay V; Hart, Joseph M; Ambegaonkar, Jatin P

2018-04-01

  Anterior cruciate ligament (ACL) injuries often occur during jump landings and can have detrimental short-term and long-term functional effects on quality of life. Despite frequently performing jump landings, dancers have lower incidence rates of ACL injury than other jump-landing athletes. Planned versus unplanned activities and footwear may explain differing ACL-injury rates among dancers and nondancers. Still, few researchers have compared landing biomechanics between dancers and nondancers.   To compare the landing biomechanics of dancers and nondancers during single-legged (SL) drop-vertical jumps.   Cross-sectional study.   Laboratory.   A total of 39 healthy participants, 12 female dancers (age = 20.9 ± 1.8 years, height = 166.4 ± 6.7 cm, mass = 63.2 ± 16.4 kg), 14 female nondancers (age = 20.2 ± 0.9 years, height = 168.9 ± 5.0 cm, mass = 61.6 ± 7.7 kg), and 13 male nondancers (age = 22.2 ± 2.7 years, height = 180.6 ± 9.7 cm, mass = 80.8 ± 13.2 kg).   Participants performed SL-drop-vertical jumps from a 30-cm-high box in a randomized order in 2 activity (planned, unplanned) and 2 footwear (shod, barefoot) conditions while a 3-dimensional system recorded landing biomechanics.   Overall peak sagittal-plane and frontal-plane ankle-, knee-, and hip-joint kinematics (joint angles) were compared across groups using separate multivariate analyses of variance followed by main-effects testing and pairwise-adjusted Bonferroni comparisons as appropriate ( P < .05).   No 3-way interactions existed for sagittal-plane or frontal-plane ankle (Wilks λ = 0.85, P = .11 and Wilks λ = 0.96, P = .55, respectively), knee (Wilks λ = 1.00, P = .93 and Wilks λ = 0.94, P = .36, respectively), or hip (Wilks λ = 0.99, P = .88 and Wilks λ = 0.97, P = .62, respectively) kinematics. We observed no group × footwear interactions for sagittal-plane or frontal-plane ankle (Wilks λ = 0.94, P = .43 and Wilks λ = 0.96, P = .55, respectively), knee (Wilks �

The effect of ankle position on the exam for first ray mobility.

PubMed

Grebing, Brett R; Coughlin, Michael J

2004-07-01

The clinical assessment of first ray motion in the sagittal plane, as originally described by Morton, is difficult to quantify. Different reports have shown inconsistent values and variability between the manual exam and examination using an external measuring device. The authors hypothesize that when performing a manual examination for evidence of increased first ray motion, the magnitude of first ray mobility varies as the position of ankle dorsiflexion/plantarflexion varies. Using an external caliper (a modified Klaue device), the authors quantified first ray motion in reference to variable ankle positions in a group of normal patients, a group of patients with untreated moderate and severe hallux valgus, a group who had undergone a successful metatarsophalangeal joint arthrodesis for hallux valgus, and a small group who had previously undergone a plantar fasciectomy. A total of 119 feet (109 patients) were measured. In addition to first ray motion, radiographic data were compared between groups. With the ankle in the neutral dorsiflexion position, the mean first ray motion was 4.9 mm for the control group, 7.0 mm for the hallux valgus group, 4.4 mm for the metatarsophalangeal fusion group, and 7.7 mm for the plantar fasciectomy group. There was a significant decrease (p < .05) in first ray motion when the ankle was moved to the dorsiflexed position for all four groups. There was a significant increase in first ray motion when the ankle was moved to the plantarflexed position (p < .01) for all groups except the plantar fasciectomy group. No significant difference in first ray motion was observed for the plantar fasciectomy group between the neutral and plantarflexed ankle positions (p < .05). The exam for first ray mobility is influenced by the position of the ankle and may explain the discrepancy between the manual exam and measurement with an external device. Recommendations for the manual exam of first ray mobility are given.

Optimal suture anchor direction in arthroscopic lateral ankle ligament repair.

PubMed

Yoshimura, Ichiro; Hagio, Tomonobu; Noda, Masahiro; Kanazawa, Kazuki; Minokawa, So; Yamamoto, Takuaki

2017-05-26

In this study, the distance between the insertion point of the suture anchors and posterior surface of the fibula during arthroscopic lateral ankle ligament repair was investigated on computed tomography (CT) images. The hypothesis of this study was that there is an optimal insertional direction of the suture anchor to avoid anchor-related complications. One hundred eleven ankles of 98 patients who had undergone three-dimensional CT scans for foot or ankle disorders without deformity of the fibula were assessed (59 males, 52 females; median age 25.5 years; age range 12-78 years). The shortest distance from the insertion point of the suture anchor to the deepest point of the fossa/top of the convex aspect of the fibula was measured on the axial plane, tilting from the longitudinal axis of the fibula at 90°, 75°, 60°, and 45°. The distance from the insertion point of the suture anchor to the posterior surface of the fibula was also measured in a direction parallel to the sagittal plane of the lateral surface of the talus on the axial plane, tilting from the longitudinal axis of the fibula at 90°, 75°, 60°, and 45°. The posterior fossa was observed in all cases on the 90° and 75° images. The distance from the insertion point to the posterior surface of the fibula in the parallel direction was 15.0 ± 3.4 mm at 90°, 17.5 ± 3.2 mm at 75°, 21.7 ± 3.3 mm at 60°, and 25.7 ± 3.6 mm at 45°. The posterior points in the parallel direction were located on the posterior fossa in 36.0% of cases at 90°, in 12.6% at 75°, and in 0.0% at 60° and 45°. The suture anchor should be directed from anterior to posterior at an angle of <45° to the longitudinal axis of the fibula, parallel to the lateral surface of the talus, to avoid passing through the fibula. Cohort study, Level III.

Ankle morphology amplifies calcaneus movement relative to triceps surae muscle shortening.

PubMed

Csapo, R; Hodgson, J; Kinugasa, R; Edgerton, V R; Sinha, S

2013-08-15

The present study investigated the mechanical role of the dorsoventral curvature of the Achilles tendon in the conversion of the shortening of the plantarflexor muscles into ankle joint rotation. Dynamic, sagittal-plane magnetic resonance spin-tagged images of the ankle joint were acquired in six healthy subjects during both passive and active plantarflexion movements driven by a magnetic resonance compatible servomotor-controlled foot-pedal device. Several points on these images were tracked to determine the 1) path and deformation of the Achilles tendon, 2) ankle's center of rotation, and 3) tendon moment arms. The degree of mechanical amplification of joint movement was calculated as the ratio of the displacements of the calcaneus and myotendinous junction. In plantarflexion, significant deflection of the Achilles tendon was evident in both the passive (165.7 ± 7.4°; 180° representing a straight tendon) and active trials (166.9 ± 8.8°). This bend in the dorsoventral direction acts to move the Achilles tendon closer to the ankle's center of rotation, resulting in an ∼5% reduction of moment arm length. Over the entire range of movement, the overall displacement of the calcaneus exceeded the displacement of the myotendinous junction by ∼37%, with the mechanical gains being smaller in dorsi- and larger in plantarflexed joint positions. This is the first study to assess noninvasively and in vivo using MRI the curvature of the Achilles tendon during both passive and active plantarflexion movements. The dorsoventral tendon curvature amplifies the shortening of the plantarflexor muscles, resulting in a greater displacement of the tendon's insertion into the calcaneus compared with its origin.

Sagittal balance and idiopathic scoliosis: does final sagittal alignment influence outcomes, degeneration rate or failure rate?

PubMed

Ilharreborde, Brice

2018-02-01

In the last decade, spine surgeons have been impacted by the "sagittal plane analysis revolution". Significant correlations have been found in adult spinal deformity (ASD) between sagittal lumbo-pelvic parameters and functional outcomes, but most of them do not apply in adolescent idiopathic scoliosis (AIS). Meanwhile, instrumentation and reduction strategies have considerably evolved. This paper aims to describe the preoperative sagittal alignment in AIS, and to report literature evidence regarding the influence of postoperative sagittal balance on complication rates, low back pain incidence and disc degeneration. A bibliographic search in Medline and Google database from 1984 to May 2017 was performed. The keywords included 'adolescent idiopathic scoliosis', 'adult scoliosis', 'sagittal alignment', 'proximal junctional kyphosis', 'distal junctional kyphosis', 'outcomes', 'low back pain' and 'complication', used individually or in combination. Algorithms of sagittal balance analysis and treatment decision have been reported in ASD, but the clinical situation is very different in children. Sagittal alignment greatly varies in AIS among the various Lenke types. Most patients are clinically balanced before surgery, but the spinal harmony is altered, with overgrowth of the anterior column and global sagittal flattening (undersestimated in 2D). The exact role of pelvic incidence and whether or not patients also use pelvic compensation to maintain balance still require further clarification. The incidence of radiological junctional failures remains highly variable, depending on definitions, cohort size and follow-up. Preoperative hyperkyphosis seems to be a consistent and relevant risk factor. Current literature does not support the recent trend to save motion segments (selective fusion), and no significant association was found between the distal level of fusion and the incidence of low back pain. Postoperative sagittal alignment seems to be more important than LIV

Single-leg drop landing movement strategies 6 months following first-time acute lateral ankle sprain injury.

PubMed

Doherty, C; Bleakley, C; Hertel, J; Caulfield, B; Ryan, J; Delahunt, E

2015-12-01

No research exists predicating a link between acute ankle sprain injury-affiliated movement patterns and those of chronic ankle instability (CAI) populations. The aim of the current study was to perform a biomechanical analysis of participants, 6 months after they sustained a first-time acute lateral ankle sprain (LAS) injury to establish this link. Fifty-seven participants with a 6-month history of first-time LAS and 20 noninjured participants completed a single-leg drop landing task on both limbs. Three-dimensional kinematic (angular displacement) and sagittal plane kinetic (moment of force) data were acquired for the joints of the lower extremity, from 200 ms pre-initial contact (IC) to 200 ms post-IC. Individual joint stiffnesses and the peak magnitude of the vertical component of the ground reaction force (GRF) were also computed. LAS participants displayed increases in hip flexion and ankle inversion on their injured limb (P < 0.05); this coincided with a reduction in the net flexion-extension moment at the hip joint, with an increase in its stiffness (P < 0.05). There was no difference in the magnitude of the peak vertical GRF for either limb compared with controls. These results demonstrate that altered movement strategies persist in participants, 6 months following acute LAS, which may precipitate the onset of CAI. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The effects of the sagittal plane malpositioning of the patella and concomitant quadriceps hypotrophy on the patellofemoral joint: a finite element analysis.

PubMed

Aksahin, Ertugrul; Kocadal, Onur; Aktekin, Cem N; Kaya, Defne; Pepe, Murad; Yılmaz, Serdar; Yuksel, H Yalcin; Bicimoglu, Ali

2016-03-01

Anterior knee pain is a common symptom after intramedullary nailing in tibia shaft fracture. Moreover, patellofemoral malalignment is also known to be a major reason for anterior knee pain. Patellofemoral malalignment predisposes to increased loading in patellar cartilage. In the previous study, we have demonstrated the quadriceps atrophy and patellofemoral malalignment after intramedullary nailing due to tibia shaft fracture. In this study, our aim was to clarify the effects of quadriceps atrophy and patellofemoral malalignment with the pathologic loading on the joint cartilage. Mesh models of patellofemoral joint were constructed with CT images and integrated with soft tissue components such as menisci and ligaments. Physiological and sagittal tilt models during extension and flexion at 15°, 30° and 60° were created generating eight models. All the models were applied with 137 N force to present the effects of normal loading and 115.7 N force for the simulation of quadriceps atrophy. Different degrees of loading were applied to evaluate the joint contact area and pressure value with the finite element analysis. There was increased patellofemoral contact area in patellar tilt models with respect to normal models. The similar loading patterns were diagnosed in all models at 0° and 15° knee flexion when 137 N force was applied. Higher loading values were obtained at 30° and 60° knee flexions in sagittal tilt models. Furthermore, in the sagittal tilt models, in which the quadriceps atrophy was simulated, the loadings at 30° and 60° knee flexion were higher than in the physiological ones. Sagittal malalignment of the patellofemoral joint is a new concept that results in different loading patterns in the patellofemoral joint biomechanics. This malalignment in sagittal plane leads to increased loading values on the patellofemoral joint at 30° and 60° of the knee flexions. This new concept should be kept in mind during the course of diagnosis and treatment

Dynamic Balance Deficits 6 Months Following First-Time Acute Lateral Ankle Sprain: A Laboratory Analysis.

PubMed

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

2015-08-01

Controlled laboratory study. To utilize kinematic and stabilometric measures to compare dynamic balance during performance of the Star Excursion Balance Test between persons 6 months following first-time lateral ankle sprain (LAS) and a noninjured control group. Biomechanical evaluation of dynamic balance in persons following first-time LAS during performance of the Star Excursion Balance Test could provide insight into the mechanisms by which individuals proceed to recover fully or develop chronic ankle instability. Sagittal plane kinematics of the lower extremity and the center-of-pressure path during the performance of the anterior, posterolateral, and posteromedial reach directions of the Star Excursion Balance Test were obtained from 69 participants 6 months following first-time acute LAS and from a control group of 20 noninjured participants. Compared to the control group, the LAS group displayed lower normalized reach distances in all 3 reach directions on the injured and noninjured limbs, with the largest observed effect size in the posterolateral direction (P = .001, ηp(2) = 0.07). The performance impairment was associated with less hip and knee flexion and ankle dorsiflexion at the point of maximum reach (P<.02), and coincided with less complexity of the center-of-pressure path (P<.05). Participants with a 6-month history of LAS exhibit a persistence of deficits previously established in the acute phase of injury.

Position of the prosthesis components in total ankle replacement and the effect on motion at the replaced joint.

PubMed

Cenni, Francesco; Leardini, Alberto; Cheli, Andrea; Catani, Fabio; Belvedere, Claudio; Romagnoli, Matteo; Giannini, Sandro

2012-03-01

In some cases of total ankle replacement, perfect alignment of the prosthetic components is not achieved. This study analyses the extent to which component positioning is critical for the final range of motion. Fourteen patients undergoing total ankle replacement were assessed preoperatively and postoperatively at seven and 13 months follow-up. X-ray pictures of the ankle were taken in static double leg stance, i.e. at neutral joint position, and in maximum plantarflexion and dorsiflexion. Measurements were obtained by a specially devised computer program based on anatomical reference points digitised on the radiograms. These allowed calculation of the position and orientation of the components in the sagittal and coronal planes, together with the joint range of motion. The mean range of motion was about 34 degrees at the first follow-up and maintained at the second. Tibial and talar components were more anterior than the mid-tibial shaft in 11 and nine patients, respectively. Mean inclination was about four degrees posterior for the tibial component and nearly one degree anterior for the talar component. A significantly larger range of motion was found in ankles both with the talar component located and inclined more anteriorly than the tibial. Correlation, though weak, was found between motion at the replaced ankle and possible residual subluxation and inclination of the components. However, a satisfactory range of motion was also achieved in those patients where recommended locations for the components could not be reached because of the size of the original joint deformity.

Kinematics analysis of ankle inversion ligamentous sprain injuries in sports: five cases from televised tennis competitions.

PubMed

Fong, Daniel Tik-Pui; Ha, Sophia Chui-Wai; Mok, Kam-Ming; Chan, Christie Wing-Long; Chan, Kai-Ming

2012-11-01

Ankle ligamentous sprain is common in sports. The most direct way to study the mechanism quantitatively is to study real injury cases; however, it is unethical and impractical to produce an injury in the laboratory. A recently developed, model-based image-matching motion analysis technique allows quantitative analysis of real injury incidents captured in televised events and gives important knowledge for the development of injury prevention protocols and equipment. To date, there have been only 4 reported cases, and there is a need to conduct more studies for a better understanding of the mechanism of ankle ligamentous sprain injury. This study presents 5 cases in tennis and a comparison with 4 previous cases for a better understanding of the mechanism of ankle ligamentous sprain injury. Case series; level of evidence, 4. Five sets of videos showing ankle sprain injuries in televised tennis competition with 2 camera views were collected. The videos were transformed, synchronized, and rendered to a 3-dimensional animation software. The dimensions of the tennis court in each case were obtained to build a virtual environment, and a skeleton model scaled to the injured athlete's height was used for the skeleton matching. Foot strike was determined visually, and the profiles of the ankle joint kinematics were individually presented. There was a pattern of sudden inversion and internal rotation at the ankle joint, with the peak values ranging from 48°-126° and 35°-99°, respectively. In the sagittal plane, the ankle joint fluctuated between plantar flexion and dorsiflexion within the first 0.50 seconds after foot strike. The peak inversion velocity ranged from 509 to 1488 deg/sec. Internal rotation at the ankle joint could be one of the causes of ankle inversion sprain injury, with a slightly inverted ankle joint orientation at landing as the inciting event. To prevent the foot from rolling over the edge to cause a sprain injury, tennis players who do lots of sideward

Ambulatory measurement of ankle kinetics for clinical applications.

PubMed

Rouhani, H; Favre, J; Crevoisier, X; Aminian, K

2011-10-13

This study aimed to design and validate the measurement of ankle kinetics (force, moment, and power) during consecutive gait cycles and in the field using an ambulatory system. An ambulatory system consisting of plantar pressure insole and inertial sensors (3D gyroscopes and 3D accelerometers) on foot and shank was used. To test this system, 12 patients and 10 healthy elderly subjects wore shoes embedding this system and walked many times across a gait lab including a force-plate surrounded by seven cameras considered as the reference system. Then, the participants walked two 50-meter trials where only the ambulatory system was used. Ankle force components and sagittal moment of ankle measured by ambulatory system showed correlation coefficient (R) and normalized RMS error (NRMSE) of more than 0.94 and less than 13% in comparison with the references system for both patients and healthy subjects. Transverse moment of ankle and ankle power showed R>0.85 and NRMSE<23%. These parameters also showed high repeatability (CMC>0.7). In contrast, the ankle coronal moment of ankle demonstrated high error and lower repeatability. Except for ankle coronal moment, the kinetic features obtained by the ambulatory system could distinguish the patients with ankle osteoarthritis from healthy subjects when measured in 50-meter trials. The proposed ambulatory system can be easily accessible in most clinics and could assess main ankle kinetics quantities with acceptable error and repeatability for clinical evaluations. This system is therefore suggested for field measurement in clinical applications. Copyright © 2011 Elsevier Ltd. All rights reserved.

Foot and ankle kinematics in patients with posterior tibial tendon dysfunction.

PubMed

Ness, Mary Ellen; Long, Jason; Marks, Richard; Harris, Gerald

2008-02-01

The purpose of this study is to provide a quantitative characterization of gait in patients with posterior tibial tendon dysfunction (PTTD), including temporal-spatial and kinematic parameters, and to compare these results to those of a Normal population. Our hypothesis was that segmental foot kinematics were significantly different in multiple segments across multiple planes. A 15 camera motion analysis system and weight-bearing radiographs were employed to evaluate 3D foot and ankle motion in a population of 34 patients with PTTD (30 females, 4 males) and 25 normal subjects (12 females, 13 males). The four-segment Milwaukee Foot Model (MFM) with radiographic indexing was used to analyze foot and ankle motion and provided kinematic data in the sagittal, coronal and transverse planes as well as temporal-spatial information. The temporal-spatial parameters revealed statistically significant deviations in all four metrics for the PTTD population. Stride length, cadence and walking speed were all significantly diminished, while stance duration was significantly prolonged (p<0.0125). Significant kinematic differences were noted between the groups (p<0.002), including: (1) diminished dorsiflexion and increased eversion of the hindfoot; (2) decreased plantarflexion of the forefoot, as well as abduction shift and loss of the varus thrust in the forefoot; and (3) decreased range of motion (ROM) with diminished dorsiflexion of the hallux. The study provides an impetus for improved orthotic and bracing designs to aid in the care of distal foot segments during the treatment of PTTD. It also provides the basis for future evaluation of surgical efficacy. The course of this investigation may ultimately lead to improved treatment planning methods, including orthotic and operative interventions.

How Well Can Modern Nonhabitual Barefoot Youth Adapt to Barefoot and Minimalist Barefoot Technology Shoe Walking, in regard to Gait Symmetry.

PubMed

Xu, Y; Hou, Q; Wang, C; Simpson, T; Bennett, B; Russell, S

2017-01-01

We aim to test how well modern nonhabitual barefoot people can adapt to barefoot and Minimalist Bare Foot Technology (MBFT) shoes, in regard to gait symmetry. 28 healthy university students (22 females/6 males) were recruited to walk on a 10-meter walkway randomly on barefoot, in MBFT shoes, and in neutral running shoes at their comfortable walking speed. Kinetic and kinematic data were collected using an 8-camera motion capture system. Data of joint angles, joint forces, and joint moments were extracted to compute a consecutive symmetry index. Compared to walking in neutral running shoes, walking barefoot led to worse symmetry of the following: ankle joint force in sagittal plane, knee joint moment in transverse plane, and ankle joint moment in frontal plane, while improving the symmetry of joint angle in sagittal plane at ankle joints and global (hip-knee-ankle) level. Walking in MBFT shoes had intermediate gait symmetry performance as compared to walking barefoot/walking in neutral running shoes. We conclude that modern nonhabitual barefoot adults will lose some gait symmetry in joint force/moment if they switch to barefoot walking without fitting in; MBFT shoe might be an ideal compromise for healthy youth as regards gait symmetry in walking.

Sagittal plane bending moments acting on the lower leg during running.

PubMed

Haris Phuah, Affendi; Schache, Anthony G; Crossley, Kay M; Wrigley, Tim V; Creaby, Mark W

2010-02-01

Sagittal bending moments acting on the lower leg during running may play a role in tibial stress fracture development. The purpose of this study was to evaluate these moments at nine equidistant points along the length of the lower leg (10% point-90% point) during running. Kinematic and ground reaction force data were collected for 20 male runners, who each performed 10 running trials. Inverse dynamics and musculoskeletal modelling techniques were used to estimate sagittal bending moments due to reaction forces and muscle contraction. The muscle moment was typically positive during stance, except at the most proximal location (10% point) on the lower leg. The reaction moment was predominantly negative throughout stance and greater in magnitude than the muscle moment. Hence, the net sagittal bending moment acting on the lower leg was principally negative (indicating tensile loads on the posterior tibia). Peak moments typically occurred around mid-stance, and were greater in magnitude at the distal, compared with proximal, lower leg. For example, the peak reaction moment at the most distal point was -9.61+ or - 2.07%Bw.Ht., and -2.73 + or - 1.18%Bw.Ht. at the most proximal point. These data suggest that tensile loads on the posterior tibia are likely to be higher toward the distal end of the bone. This finding may explain the higher incidence of stress fracture in the distal aspect of the tibia, observed by some authors. Stress fracture susceptibility will also be influenced by bone strength and this should also be accounted for in future studies. Copyright 2009 Elsevier B.V. All rights reserved.

Standing sagittal alignment of the whole axial skeleton with reference to the gravity line in humans.

PubMed

Hasegawa, Kazuhiro; Okamoto, Masashi; Hatsushikano, Shun; Shimoda, Haruka; Ono, Masatoshi; Homma, Takao; Watanabe, Kei

2017-05-01

between offset of C7 vertebra from the sagittal vertical axis (a vertical line drawn through the posterior superior corner of the sacrum in the sagittal plane) and age, but no correlation was detected between the centre of the acoustic meati-GL offset and age. Cervical lordosis (CL), pelvic tilt (PT), pelvic incidence, hip extension, knee flexion and ankle dorsiflexion increased significantly with age. Our results revealed that aging induces trunk stooping, but the global alignment is compensated for by an increase in the CL, PT and knee flexion, with the main function of CL and PT to maintain a horizontal gaze in a healthy population. © 2017 The Authors Journal of Anatomy published by John Wiley & Sons Ltd on behalf of Anatomical Society.

Quantification of shoulder and elbow passive moments in the sagittal plane as a function of adjacent angle fixations.

PubMed

Kodek, Timotej; Munih, Marko

2003-01-01

The goal of this study was an assessment of the shoulder and elbow joint passive moments in the sagittal plane for six healthy individuals. Either the shoulder or elbow joints were moved at a constant speed, very slowly throughout a large portion of their range by means of an industrial robot. During the whole process the arm was held fully passively, while the end point force data and the shoulder, elbow and wrist angle data were collected. The presented method unequivocally reveals a large passive moment adjacent angle dependency in the central angular range, where most everyday actions are performed. It is expected to prove useful in the future work when examining subjects with neuromuscular disorders. Their passive moments may show a fully different pattern than the ones obtained in this study.

Analysis of the Pelvic Functional Orientation in the Sagittal Plane: A Radiographic Study With EOS 2D/3D Technology.

PubMed

Loppini, Mattia; Longo, Umile Giuseppe; Ragucci, Pasquala; Trenti, Nicoletta; Balzarini, Luca; Grappiolo, Guido

2017-03-01

We investigated the relationship between pelvic incidence (PI) with anterior pelvic plane angle (APPA), pelvic tilt (PT) angle, and sacral slope (SS) in standing and sitting positions to identify the best parameter expressing the pelvic functional orientation in the sagittal plane. We enrolled 109 consecutive patients (M:F = 43:66) eligible for a primary total hip arthroplasty (THA) with an average age of 63.4 years (15-85). EOS 2D/3D radiography was performed in standing and sitting positions before THA to evaluate the functional pelvic orientation. 3D images took into account the patient-specific sagittal balance measuring APPA, PT, SS, and PI. In standing position, functional parameters measured 5° ± 7.1 for APPA, 11° ± 8.3 for PT, 43° ± 8.5 for SS, and 53° ± 10.9 for PI. In sitting position, they were -18° ± 10.4 for APPA, 34° ± 11.8 for PT, 20° ± 12.6 for SS, and 54° ± 10.9 for PI. There was no significant difference between men and women in terms of the functional parameters in both positions. No relationship was found between APPA and PI in both positions. SS correlated with PI in standing (r = 0.66; P < .0001; R 2  = 0.44) and sitting (r = 0.51; P < .0001; R 2  = 0.26). PT correlated with PI in standing (r = 0.65; P < .0001; R 2  = 0.42) and sitting (r = 0.38; P < .0001; R 2  = 0.14). SS shows the highest correlation with functional pelvic tilt. The study suggests that adjustments in acetabular anteversion during primary THA should be based on SS. Copyright © 2016 Elsevier Inc. All rights reserved.

The association between whole body sagittal balance and risk of falls among elderly patients seeking treatment for back pain.

PubMed

Kim, J; Hwang, J Y; Oh, J K; Park, M S; Kim, S W; Chang, H; Kim, T-H

2017-05-01

The objective of this study was to assess the association between whole body sagittal balance and risk of falls in elderly patients who have sought treatment for back pain. Balanced spinal sagittal alignment is known to be important for the prevention of falls. However, spinal sagittal imbalance can be markedly compensated by the lower extremities, and whole body sagittal balance including the lower extremities should be assessed to evaluate actual imbalances related to falls. Patients over 70 years old who visited an outpatient clinic for back pain treatment and underwent a standing whole-body radiograph were enrolled. Falls were prospectively assessed for 12 months using a monthly fall diary, and patients were divided into fallers and non-fallers according to the history of falls. Radiological parameters from whole-body radiographs and clinical data were compared between the two groups. A total of 144 patients (120 female patients and 24 male patients) completed a 12-month follow-up for assessing falls. A total of 31 patients (21.5%) reported at least one fall within the 12-month follow-up. In univariate logistic regression analysis, the risk of falls was significantly increased in older patients and those with more medical comorbidities, decreased lumbar lordosis, increased sagittal vertical axis, and increased horizontal distance between the C7 plumb line and the centre of the ankle (C7A). Increased C7A was significantly associated with increased risk of falls even after multivariate adjustment. Whole body sagittal balance, measured by the horizontal distance between the C7 plumb line and the centre of the ankle, was significantly associated with risk of falls among elderly patients with back pain. Cite this article : J. Kim, J. Y. Hwang, J. K. Oh, M. S. Park, S. W. Kim, H. Chang, T-H. Kim. The association between whole body sagittal balance and risk of falls among elderly patients seeking treatment for back pain. Bone Joint Res 2017;6:-344. DOI: 10

Walking sagittal balance correction by pedicle subtraction osteotomy in adults with fixed sagittal imbalance.

PubMed

Yagi, Mitsuru; Kaneko, Shinjiro; Yato, Yoshiyuki; Asazuma, Takashi; Machida, Masafumi

2016-08-01

Pedicle subtraction osteotomy (PSO) is widely used to treat severe fixed sagittal imbalance. However, the effect of PSO on balance has not been fully documented. The aim of this study was to assess dynamic walking balance after PSO to treat fixed sagittal imbalance. Gait and balance were assessed in 15 consecutive adult female patients who had been treated by PSO for a fixed sagittal imbalance and compare patients' preop and postop dynamic walking balance with that of 15 age- and gender-matched healthy volunteers (HV). Each patient's chart, X-rays, pre and postop SRS22 outcome scores, and ODI were reviewed. Means were compared by Mann-Whitney U test and Chi-square test. The mean age was 66.3 years (51-74 years). The mean follow-up was 2.7 years (2-3.5 years). The C7PL and GL, measured on the force platform, were both improved from 24.2 ± 7.3 cm and 27.6 ± 9.4 to 5.4 ± 2.6 cm and 7.2 ± 3.4 cm, respectively. The baseline hip ROM was significantly smaller in patients compared to HV, whereas no significant difference was observed in the knee or ankle ROM. The pelvic tilt (preop -0.4° ± 1.4°, postop 8.9° ± 1.0°), and maximum hip-extension angle (preop -1.2° ± 14.2°, postop -11.2° ± 7.2°) were also improved after surgery. Cadence (116 s/min), stance-swing ratio (stance 63.2 % vs. swing 36.8 %), and stride (98.0 cm) were all increased after surgery. On the other hand, gait velocity was significantly slower in the PSO group at both pre and postop than in HV (PSO 53.3 m/min at preop and 58.8 m/min at postop vs. HV 71.1 m/min, p = 0.04). Despite a mild residual spinal-pelvic malalignment, PSO restored sagittal alignment and balance satisfactorily and has improved the gait pattern.

Validity of an ankle joint motion and position sense measurement system and its application in healthy subjects and patients with ankle sprain.

PubMed

Lin, Chueh-Ho; Chiang, Shang-Lin; Lu, Liang-Hsuan; Wei, Shun-Hwa; Sung, Wen-Hsu

2016-07-01

Ankle motion and proprioception in multiple axis movements are crucial for daily activities. However, few studies have developed and used a multiple axis system for measuring ankle motion and proprioception. This study was designed to validate a novel ankle haptic interface system that measures the ankle range of motion (ROM) and joint position sense in multiple plane movements, investigating the proprioception deficits during joint position sense tasks for patients with ankle instability. Eleven healthy adults (mean ± standard deviation; age, 24.7 ± 1.9 years) and thirteen patients with ankle instability were recruited in this study. All subjects were asked to perform tests to evaluate the validity of the ankle ROM measurements and underwent tests for validating the joint position sense measurements conducted during multiple axis movements of the ankle joint. Pearson correlation was used for validating the angular position measurements obtained using the developed system; the independent t test was used to investigate the differences in joint position sense task performance for people with or without ankle instability. The ROM measurements of the device were linearly correlated with the criterion standards (r = 0.99). The ankle instability and healthy groups were significantly different in direction, absolute, and variable errors of plantar flexion, dorsiflexion, inversion, and eversion (p < 0.05). The results demonstrate that the novel ankle joint motion and position sense measurement system is valid and can be used for measuring the ankle ROM and joint position sense in multiple planes and indicate proprioception deficits for people with ankle instability. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Customized Noise-Stimulation Intensity for Bipedal Stability and Unipedal Balance Deficits Associated With Functional Ankle Instability

PubMed Central

Ross, Scott E.; Linens, Shelley W.; Wright, Cynthia J.; Arnold, Brent L.

2013-01-01

Context: Stochastic resonance stimulation (SRS) administered at an optimal intensity could maximize the effects of treatment on balance. Objective: To determine if a customized optimal SRS intensity is better than a traditional SRS protocol (applying the same percentage sensory threshold intensity for all participants) for improving double- and single-legged balance in participants with or without functional ankle instability (FAI). Design: Case-control study with an embedded crossover design. Setting: Laboratory. Patients or Other Participants: Twelve healthy participants (6 men, 6 women; age = 22 ± 2 years, height = 170 ± 7 cm, mass = 64 ± 10 kg) and 12 participants (6 men, 6 women; age = 23 ± 3 years, height = 174 ± 8 cm, mass = 69 ± 10 kg) with FAI. Intervention(s): The SRS optimal intensity level was determined by finding the intensity from 4 experimental intensities at the percentage sensory threshold (25% [SRS25], 50% [SRS50], 75% [SRS75], 90% [SRS90]) that produced the greatest improvement in resultant center-of-pressure velocity (R-COPV) over a control condition (SRS0) during double-legged balance. We examined double- and single-legged balance tests, comparing optimal SRS (SRSopt1) and SRS0 using a battery of center-of-pressure measures in the frontal and sagittal planes. Main Outcome Measure(s): Anterior-posterior (A-P) and medial-lateral (M-L) center-of-pressure velocity (COPV) and center-of-pressure excursion (COPE), R-COPV, and 95th percentile center-of-pressure area ellipse (COPA-95). Results: Data were organized into bins that represented optimal (SRSopt1), second (SRSopt2), third (SRSopt3), and fourth (SRSopt4) improvement over SRS0. The SRSopt1 enhanced R-COPV (P ≤ .05) over SRS0 and other SRS conditions (SRS0 = 0.94 ± 0.32 cm/s, SRSopt1 = 0.80 ± 0.19 cm/s, SRSopt2 = 0.88 ± 0.24 cm/s, SRSopt3 = 0.94 ± 0.25 cm/s, SRSopt4 = 1.00 ± 0.28 cm/s). However, SRS did not improve R-COPV over SRS0 when data were categorized by sensory threshold

Evaluation of the lambda model for human postural control during ankle strategy.

PubMed

Micheau, Philippe; Kron, Aymeric; Bourassa, Paul

2003-09-01

An accurate modeling of human stance might be helpful in assessing postural deficit. The objective of this article is to validate a mathematical postural control model for quiet standing posture. The postural dynamics is modeled in the sagittal plane as an inverted pendulum with torque applied at the ankle joint. The torque control system is represented by the physiological lambda model. Two neurophysiological command variables of the central nervous system, designated lambda and micro, establish the dynamic threshold muscle at which motoneuron recruitment begins. Kinematic data and electromyographic signals were collected on four young males in order to measure small voluntary sway and quiet standing posture. Validation of the mathematical model was achieved through comparison of the experimental and simulated results. The mathematical model allows computation of the unmeasurable neurophysiological commands lambda and micro that control the equilibrium position and stability. Furthermore, with the model it is possible to conclude that low-amplitude body sway during quiet stance is commanded by the central nervous system.

The Effect of Sagittal Plane Deformities after Tibial Plateau Fractures to Functions and Instability of Knee Joint.

PubMed

Erdil, M; Yildiz, F; Kuyucu, E; Sayar, Ş; Polat, G; Ceylan, H H; Koçyiğit, F

2016-01-01

The objective of this study is to evaluate the effect of posterior tibial slope after fracture healing on antero-posterior knee laxity, functional outcome and patient satisfaction. 126 patients who were treated for tibial plateau fractures between 2008-2013 in the orthopedics and traumatology department of our institution were evaluated for the study. Patients were treated with open reduction and internal fixation, arthroscopy assisted minimally invasive osteosynthesis or conservative treatment. Mean posterior tibial slope after the treatment was 6.91 ± 5.11 and there was no significant difference when compared to the uninvolved side 6.42 ± 4,21 (p = 0.794). Knee laxity in anterior-posterior plane was 6.14 ± 2.11 and 5.95 ± 2.25 respectively on healthy and injured side. The difference of mean laxity in anterior-posterior plane between two sides was statistically significant. In this study we found no difference in laxity between the injured and healthy knees. However Tegner score decreased significantly in patients who had greater laxity difference between the knees. We did not find significant difference between fracture type and laxity, IKDC functional scores independent of the ligamentous injury. In conclusion despite coronal alignment is taken into consideration in treatment of tibial plateau fractures, sagittal alignment is reasonably important for stability and should not be ignored.

Kinematic alterations of the lower limbs and pelvis during an ascending stairs task are associated with the degree of knee osteoarthritis severity.

PubMed

Gonçalves, Glaucia Helena; Selistre, Luiz Fernando Approbato; Petrella, Marina; Mattiello, Stela Márcia

2017-03-01

Individuals with knee osteoarthritis (OA) generally demonstrate great difficulty in ascending stairs. The strategies and compensations used by these individuals in stair activities have not been fully established. The purpose of this study was to investigate the joint kinematics of the pelvis, hip, knee and ankle throughout the gait cycle, in the sagittal and frontal planes, in individuals with mild and moderate knee OA, during an ascending stairs task. Thirty-one individuals with knee OA and 19 controls were subjected to clinical and radiographic analysis, divided into three groups: control, mild knee OA, and moderate knee OA. Participants answered a self-reported questionnaire, carried out performance-based tests, and their kinematic data were recorded during an ascending stairs task using an eight-camera Qualisys 3D-Motion analysis system. The individuals with moderate degrees of knee OA demonstrated kinematic alterations in the pelvis, hip, knee, and ankle in the sagittal plane. The individuals with mild degrees of knee OA demonstrated kinematic alterations of the hip in the frontal plane, and kinematic alterations of the ankle in the sagittal plane. The ascending stairs task allowed verification of meaningful information regarding gait strategies used by individuals with mild and moderate knee OA. The strategies of these two groups of individuals are different for this task, although more pronounced in individuals with moderate knee OA. The findings should be taken into account in the development of rehabilitation programs. Copyright © 2017 Elsevier B.V. All rights reserved.

Rotation of intramedullary alignment rods affects distal femoral cutting plane in total knee arthroplasty.

PubMed

Maderbacher, Günther; Matussek, Jan; Keshmiri, Armin; Greimel, Felix; Baier, Clemens; Grifka, Joachim; Maderbacher, Hermann

2018-02-17

Intramedullary rods are widely used to align the distal femoral cut in total knee arthroplasty. We hypothesised that both coronal (varus/valgus) and sagittal (extension/flexion) cutting plane are affected by rotational changes of intramedullary femoral alignment guides. Distal femoral cuts using intramedullary alignment rods were simulated by means of a computer-aided engineering software in 4°, 6°, 8°, 10°, and 12° of valgus in relation to the femoral anatomical axis and 4° extension, neutral, as well as 4°, 8°, and 12° of flexion in relation to the femoral mechanical axis. This reflects the different angles between anatomical and mechanical axis in coronal and sagittal planes. To assess the influence of rotation of the alignment guide on the effective distal femoral cutting plane, all combinations were simulated with the rod gradually aligned from 40° of external to 40° of internal rotation. Rotational changes of the distal femoral alignment guides affect both the coronal and sagittal cutting planes. When alignment rods are intruded neutrally with regards to sagittal alignment, external rotation causes flexion, while internal rotation causes extension of the sagittal cutting plane. Simultaneously the coronal effect (valgus) decreases resulting in an increased varus of the cutting plane. However, when alignment rods are intruded in extension or flexion partly contradictory effects are observed. Generally the effect increases with the degree of valgus preset, rotation and flexion. As incorrect rotation of intramedullary alignment guides for distal femoral cuts causes significant cutting errors, exact rotational alignment is crucial. Coronal cutting errors in the distal femoral plane might result in overall leg malalignment, asymmetric extension gaps and subsequent sagittal cutting errors.

Mid-callosal plane determination using preferred directions from diffusion tensor images

NASA Astrophysics Data System (ADS)

Costa, André L.; Rittner, Letícia; Lotufo, Roberto A.; Appenzeller, Simone

2015-03-01

The corpus callosum is the major brain structure responsible for inter{hemispheric communication between neurons. Many studies seek to relate corpus callosum attributes to patient characteristics, cerebral diseases and psychological disorders. Most of those studies rely on 2D analysis of the corpus callosum in the mid-sagittal plane. However, it is common to find conflicting results among studies, once many ignore methodological issues and define the mid-sagittal plane based on precary or invalid criteria with respect to the corpus callosum. In this work we propose a novel method to determine the mid-callosal plane using the corpus callosum internal preferred diffusion directions obtained from diffusion tensor images. This plane is analogous to the mid-sagittal plane, but intended to serve exclusively as the corpus callosum reference. Our method elucidates the great potential the directional information of the corpus callosum fibers have to indicate its own referential. Results from experiments with five image pairs from distinct subjects, obtained under the same conditions, demonstrate the method effectiveness to find the corpus callosum symmetric axis relative to the axial plane.

Altered visual focus on sensorimotor control in people with chronic ankle instability.

PubMed

Terada, Masafumi; Ball, Lindsay M; Pietrosimone, Brian G; Gribble, Phillip A

2016-01-01

The purpose of this investigation was to examine the effects of the combination of chronic ankle instability (CAI) and altered visual focus on strategies for dynamic stability during a drop-jump task. Nineteen participants with self-reported CAI and 19 healthy participants performed a drop-jump task in looking-up and looking-down conditions. For the looking-up condition, participants looked up and read a random number that flashed on a computer monitor. For the looking-down condition, participants focused their vision on the force plate. Sagittal- and frontal-plane kinematics in the hip, knee and ankle were calculated at the time points of 100 ms pre-initial foot contact to ground and at IC. The resultant vector time to stabilisation was calculated with ground reaction force data. The CAI group demonstrated less hip flexion at the point of 100 ms pre-initial contact (P < 0.01), and less hip flexion (P = 0.03) and knee flexion at initial contact (P = 0.047) compared to controls. No differences in kinematics or dynamic stability were observed in either looking-up or looking-down conditions (P > 0.05). Altered visual focus did not influence movement patterns during the drop-jump task, but the presence of CAI did. The current data suggests that centrally mediated changes associated with CAI may lead to global alterations in the sensorimotor control.

Differences in kinematic control of ankle joint motions in people with chronic ankle instability.

PubMed

Kipp, Kristof; Palmieri-Smith, Riann M

2013-06-01

People with chronic ankle instability display different ankle joint motions compared to healthy people. The purpose of this study was to investigate the strategies used to control ankle joint motions between a group of people with chronic ankle instability and a group of healthy, matched controls. Kinematic data were collected from 11 people with chronic ankle instability and 11 matched control subjects as they performed a single-leg land-and-cut maneuver. Three-dimensional ankle joint angles were calculated from 100 ms before, to 200 ms after landing. Kinematic control of the three rotational ankle joint degrees of freedom was investigated by simultaneously examining the three-dimensional co-variation of plantarflexion/dorsiflexion, toe-in/toe-out rotation, and inversion/eversion motions with principal component analysis. Group differences in the variance proportions of the first two principal components indicated that the angular co-variation between ankle joint motions was more linear in the control group, but more planar in the chronic ankle instability group. Frontal and transverse plane motions, in particular, contributed to the group differences in the linearity and planarity of angular co-variation. People with chronic ankle instability use a different kinematic control strategy to coordinate ankle joint motions during a single-leg landing task. Compared to the healthy group, the chronic ankle instability group's control strategy appeared to be more complex and involved joint-specific contributions that would tend to predispose this group to recurring episodes of instability. Copyright © 2013 Elsevier Ltd. All rights reserved.

The effects of prosthetic foot stiffness on transtibial amputee walking mechanics and balance control during turning.

PubMed

Shell, Courtney E; Segal, Ava D; Klute, Glenn K; Neptune, Richard R

2017-11-01

Little evidence exists regarding how prosthesis design characteristics affect performance in tasks that challenge mediolateral balance such as turning. This study assesses the influence of prosthetic foot stiffness on amputee walking mechanics and balance control during a continuous turning task. Three-dimensional kinematic and kinetic data were collected from eight unilateral transtibial amputees as they walked overground at self-selected speed clockwise and counterclockwise around a 1-meter circle and along a straight line. Subjects performed the walking tasks wearing three different ankle-foot prostheses that spanned a range of sagittal- and coronal-plane stiffness levels. A decrease in stiffness increased residual ankle dorsiflexion (10-13°), caused smaller adaptations (<5°) in proximal joint angles, decreased residual and increased intact limb body support, increased residual limb propulsion and increased intact limb braking for all tasks. While changes in sagittal-plane joint work due to decreased stiffness were generally consistent across tasks, effects on coronal-plane hip work were task-dependent. When the residual limb was on the inside of the turn and during straight-line walking, coronal-plane hip work increased and coronal-plane peak-to-peak range of whole-body angular momentum decreased with decreased stiffness. Changes in sagittal-plane kinematics and kinetics were similar to those previously observed in straight-line walking. Mediolateral balance improved with decreased stiffness, but adaptations in coronal-plane angles, work and ground reaction force impulses were less systematic than those in sagittal-plane measures. Effects of stiffness varied with the residual limb inside versus outside the turn, which suggests that actively adjusting stiffness to turn direction may be beneficial. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparing preseason frontal and sagittal plane plyometric programs on vertical jump height in high-school basketball players.

PubMed

King, Jeffrey A; Cipriani, Daniel J

2010-08-01

The primary purpose of this study was to evaluate whether frontal plane (FP) plyometrics, which are defined as plyometrics dominated with a lateral component, would produce similar increases in vertical jump height (VJH) compared to sagittal plane (SP) Plyometrics. Thirty-two junior varsity and varsity high-school basketball players participated in 6 weeks of plyometric training. Players participated in either FP or SP plyometrics for the entire study. Vertical jump height was measured on 3 occasions: preintervention (baseline), at week 3 of preparatory training, and at week 6 of training. Descriptive statistics were calculated for VJH. A 2-way analysis of variance (ANOVA) with repeated measures was used to test the difference in mean vertical jump scores using FP and SP training modalities. Results showed a significant effect over time for vertical jump (p < 0.001). Moreover, a significant time by protocol interaction was noted (p < 0.032). A 1-way ANOVA demonstrated that only the SP group demonstrated improvements over time, in VJH, p < 0.05. The FP group did not improve statistically. The data from this study suggest that FP plyometric training did not have a significant effect on VJH and significant improvement in VJH was seen in subjects participating in SP plyometrics thus reinforcing the specificity principle of training. However, coaches should implement both types of plyometrics because both training modalities can improve power and quickness among basketball players.

A three-year prospective comparative gait study between patients with ankle arthrodesis and arthroplasty.

PubMed

Segal, Ava D; Cyr, Krista M; Stender, Christina J; Whittaker, Eric C; Hahn, Michael E; Orendurff, Michael S; Ledoux, William R; Sangeorzan, Bruce J

2018-05-01

End-stage ankle arthritis is a debilitating condition that often requires surgical intervention after failed conservative treatments. Ankle arthrodesis is a common surgical option, especially for younger and highly active patients; however, ankle arthroplasty has become increasingly popular as advancements in implant design improve device longevity. The longitudinal differences in biomechanical outcomes between these surgical treatments remain indistinct, likely due to the challenges associated with objective study of a heterogeneous population. Patients scheduled for arthroplasty (n = 27) and arthrodesis (n = 20) were recruited to participate in this three-year prospective study. Postoperative functional outcomes were compared at distinct annual time increments using measures of gait analysis, average daily step count and survey score. Both surgical groups presented reduced pain, improved survey scores, and increased walking speed at the first-year postoperative session, which were generally consistent across the three-year follow-up. Arthrodesis patients walked with decreased sagittal ankle RoM, increased sagittal hip RoM, increased step length, and increased transient force at heel strike, postoperatively. Arthroplasty patients increased ankle RoM and cadence, with no changes in hip RoM, step length or heel strike transient force. Most postoperative changes were detected at the first-year follow-up session and maintained across the three-year time period. Despite generally favorable outcomes associated with both surgeries, several underlying postoperative biomechanical differences were detected, which may have long-term functional consequences. Furthermore, neither technique was able to completely restore gait biomechanics to the levels of the contralateral unaffected limb, leaving potential for the development of improved surgical and rehabilitative treatments. Published by Elsevier Ltd.

Prospectively identified deficits in sagittal plane hip-ankle coordination in female athletes who sustain a second anterior cruciate ligament injury after anterior cruciate ligament reconstruction and return to sport.

PubMed

Paterno, Mark V; Kiefer, Adam W; Bonnette, Scott; Riley, Michael A; Schmitt, Laura C; Ford, Kevin R; Myer, Gregory D; Shockley, Kevin; Hewett, Timothy E

2015-12-01

Athletes who return to sport after anterior cruciate ligament reconstruction are at increased risk of future ACL injury. Altered coordination of lower extremity motion may increase this risk. The purpose of this study was to prospectively determine if altered lower extremity coordination patterns exist in athletes who go on to sustain a 2nd anterior cruciate ligament injury. Sixty-one female athletes who were cleared to return to sport after anterior cruciate ligament reconstruction were included. Hip-ankle coordination was assessed prior to return to sport with a dynamic postural coordination task. Within 12 months, 14 patients sustained a 2nd ACL injury. Fourteen matched subjects were selected for comparative analysis. Cross-recurrence quantification analysis characterized hip-ankle coordination patterns. A group × target speed (slow vs. fast) × leg (involved vs. uninvolved) analysis of variance was used to identify differences. A main effect of group (P = 0.02) indicated that the single injury group exhibited more stable hip-ankle coordination [166.2 (18.9)] compared to the 2nd injury group [108.4 (10.1)]. A leg × group interaction was also observed (P = .04). The affected leg of the single injury group exhibited more stable coordination [M = 187.1 (23.3)] compared to the affected leg of the 2nd injury group [M = 110.13 (9.8)], P = 0.03. Hip-ankle coordination was altered in female athletes who sustained a 2nd anterior cruciate ligament injury after return to sport. Failure to coordinate lower extremity movement in the absence of normal knee proprioception may place the knee at risk. Copyright © 2015 Elsevier Ltd. All rights reserved.

Prospectively Identified Deficits in Sagittal Plane Hip-Ankle Coordination in Female Athletes who Sustain a Second Anterior Cruciate Ligament Injury after Anterior Cruciate Ligament Reconstruction and Return to Sport

PubMed Central

Paterno, Mark V.; Kiefer, Adam W.; Bonnette, Scott; Riley, Michael A.; Schmitt, Laura C.; Ford, Kevin R.; Myer, Gregory D.; Shockley, Kevin; Hewett, Timothy E.

2015-01-01

Background Athletes who return to sport after anterior cruciate ligament reconstruction are at increased risk of future ACL injury. Altered coordination of lower extremity motion may increase this risk. The purpose of this study was to prospectively determine if altered lower extremity coordination patterns exist in athletes who go on to sustain a 2nd anterior cruciate ligament injury. Methods Sixty-one female athletes who were medically cleared to return to sport after anterior cruciate ligament reconstruction were included. Hip-ankle coordination was assessed prior to return to sport with a dynamic postural coordination task. Within 12 months, 14 patients sustained a 2nd ACL injury. Fourteen matched subjects were selected for comparative analysis. Cross-recurrence quantification analysis characterized hip-ankle coordination patterns. A group × target speed (slow vs. fast) × leg (involved vs. uninvolved) analysis of variance was used to identify coordination differences. Findings A main effect of group (p = 0.02) indicated that the single injury group exhibited more stable hip-ankle coordination [166.2 (18.9)] compared to the 2nd injury group [108.4 (10.1)]. A leg × group interaction was also observed (p = .04). The affected leg of the single injury group exhibited more stable coordination [M = 187.1 (23.3)] compared to the affected leg of the 2nd injury group [M = 110.13 (9.8)], p = 0.03. Interpretation Hip-ankle coordination was altered in female athletes who sustained a 2nd anterior cruciate ligament injury after return to sport. Failure to coordinate lower extremity movement in the absence of normal knee proprioception may place the knee at high-risk. PMID:26416200

Changes in lower extremity movement and power absorption during forefoot striking and barefoot running.

PubMed

Williams, D S Blaise; Green, Douglas H; Wurzinger, Brian

2012-10-01

Both forefoot strike shod (FFS) and barefoot (BF) running styles result in different mechanics when compared to rearfoot strike (RFS) shod running. Additionally, running mechanics of FFS and BF running are similar to one another. Comparing the mechanical changes occurring in each of these patterns is necessary to understand potential benefits and risks of these running styles. The authors hypothesized that FFS and BF conditions would result in increased sagittal plane joint angles at initial contact and that FFS and BF conditions would demonstrate a shift in sagittal plane joint power from the knee to the ankle when compared to the RFS condition. Finally, total lower extremity power absorption will be least in BF and greatest in the RFS shod condition. The study included 10 male and 10 female RFS runners who completed 3-dimensional running analysis in 3 conditions: shod with RFS, shod with FFS, and BF. Variables were the angles of plantarflexion, knee flexion, and hip flexion at initial contact and peak sagittal plane joint power at the hip, knee, and ankle during stance phase. Running with a FFS pattern and BF resulted in significantly greater plantarflexion and significantly less negative knee power (absorption) when compared to shod RFS condition. FFS condition runners landed in the most plantarflexion and demonstrated the most peak ankle power absorption and lowest knee power absorption between the 3 conditions. BF and FFS conditions demonstrated decreased total lower extremity power absorption compared to the shod RFS condition but did not differ from one another. BF and FFS running result in reduced total lower extremity power, hip power and knee power and a shift of power absorption from the knee to the ankle. Alterations associated with BF running patterns are present in a FFS pattern when wearing shoes. Additionally, both patterns result in increased demand at the foot and ankle as compared to the knee.

Biomechanical analysis of gait waveform data: exploring differences between shod and barefoot running in habitually shod runners.

PubMed

Tam, Nicholas; Prins, Danielle; Divekar, Nikhil V; Lamberts, Robert P

2017-10-01

The aim of this study was to utilise one-dimensional statistical parametric mapping to compare differences between biomechanical and electromyographical waveforms in runners when running in barefoot or shod conditions. Fifty habitually shod runners were assessed during overground running at their current 10-km race running speed. Electromyography, kinematics and ground reaction forces were collected during these running trials. Joint kinetics were calculated using inverse dynamics. One-dimensional statistical parametric mapping one sample t-test was conducted to assess differences over an entire gait cycle on the variables of interest when barefoot or shod (p<0.05). Only sagittal plane differences were found between barefoot and shod conditions at the knee during late stance (18-23% of the gait cycle) and swing phase (74-90%); at the ankle early stance (0-6%), mid-stance (28-38%) and swing phase (81-100%). Differences in sagittal plane moments were also found at the ankle during early stance (2, 4-5%) and knee during early stance (5-11%). Condition differences were also found in vertical ground reaction force during early stance between (3-10%). An acute bout of barefoot running in habitual shod runners invokes temporal differences throughout the gait cycle. Specifically, a co-ordinative responses between the knee and ankle joint in the sagittal plane with a delay in the impact transient peak; onset of the knee extension and ankle plantarflexion moment in the shod compared to barefoot condition was found. This appears to affect the delay in knee extension and ankle plantarflexion during late stance. This study provides a glimpse into the co-ordination of the lower limb when running in differing footwear. Copyright © 2017 Elsevier B.V. All rights reserved.

Can axial-based nodal size criteria be used in other imaging planes to accurately determine "enlarged" head and neck lymph nodes?

PubMed

Bartlett, Eric S; Walters, Thomas D; Yu, Eugene

2013-01-01

Objective. We evaluate if axial-based lymph node size criteria can be applied to coronal and sagittal planes. Methods. Fifty pretreatment computed tomographic (CT) neck exams were evaluated in patients with head and neck squamous cell carcinoma (SCCa) and neck lymphadenopathy. Axial-based size criteria were applied to all 3 imaging planes, measured, and classified as "enlarged" if equal to or exceeding size criteria. Results. 222 lymph nodes were "enlarged" in one imaging plane; however, 53.2% (118/222) of these were "enlarged" in all 3 planes. Classification concordance between axial versus coronal/sagittal planes was poor (kappa = -0.09 and -0.07, resp., P < 0.05). The McNemar test showed systematic misclassification when comparing axial versus coronal (P < 0.001) and axial versus sagittal (P < 0.001) planes. Conclusion. Classification of "enlarged" lymph nodes differs between axial versus coronal/sagittal imaging planes when axial-based nodal size criteria are applied independently to all three imaging planes, and exclusively used without other morphologic nodal data.

Sagittal endplate morphology of the lower lumbar spine.

PubMed

Lakshmanan, Palaniappan; Purushothaman, Balaji; Dvorak, Vlasta; Schratt, Walter; Thambiraj, Sathya; Boszczyk, Maximilian

2012-05-01

The sagittal profile of lumbar endplates is discrepant from current simplified disc replacement and fusion device design. Endplate concavity is symmetrical in the coronal plane but shows considerable variability in the sagittal plane, which may lead to implant-endplate mismatch. The aim of this investigation is to provide further analysis of the sagittal endplate morphology of the mid to lower lumbar spine study (L3–S1), thereby identifying the presence of common endplate shape patterns across these levels and providing morphological reference values complementing the findings of previous studies. Observational study. A total of 174 magnetic resonance imaging (MRI) scans of the adult lumbar spine from the digital archive of our centre, which met the inclusion criteria, were studied. Superior (SEP) and inferior (IEP) endplate shape was divided into flat (no concavity), oblong (homogeneous concavity) and ex-centric (inhomogeneous concavity). The concavity depth (ECD) and location of concavity apex (ECA) relative to endplate diameter of the vertebrae L3–S1 were determined. Flat endplates were only predominant at the sacrum SEP (84.5%). The L5 SEP was flat in 24.7% and all other endplates in less than 10%. The majority of endplates were concave with a clear trend of endplate shape becoming more ex-centric from L3 IEP (56.9% oblong vs. 37.4% ex-centric) to L5 IEP (4% oblong vs. 94.3% ex-centric). Ex-centric ECA were always found in the posterior half of the lumbar endplates. Both the oblong and ex-centric ECD was 2-3 mm on average with the IEP of a motion segment regularly possessing the greater depth. A sex- or age-related difference could not be found. The majority of lumbar endplates are concave, while the majority of sacral endplates are flat. An oblong and an ex-centric endplate shape can be distinguished, whereby the latter is more common at the lower lumbar levels. The apex of the concavity of ex-centric discs is located in the posterior half of the endplate

[Dislocation of the ankle without simoustaneously fracture of the bones].

PubMed

Qayyum, Faiza; Qayyum, Abbas Ali; Sahlstrüm, Sven Arne

2014-09-01

The ankle is a unique modified saddle joint that, together with the subtalar joint, provides range of motion in several physical planes while maintaining stability. The ankle complex functions as a pivoting structure positioned to bear the entire weight of the body which leaves it vulnerable to injuries. Pure dislocation without associated fracture is rare; however, cases of isolated ankle dislocation without fracture have been reported. We report a case of a closed ankle dislocation without an associated fracture in a 17-year-old boy.

The effect of changing plantarflexion resistive moment of an articulated ankle-foot orthosis on ankle and knee joint angles and moments while walking in patients post stroke

PubMed Central

Kobayashi, Toshiki; Singer, Madeline L.; Orendurff, Michael S.; Gao, Fan; Daly, Wayne K.; Foreman, K. Bo

2015-01-01

Background The adjustment of plantarflexion resistive moment of an articulated ankle-foot orthosis is considered important in patients post stroke, but the evidence is still limited. Therefore, the aim of this study was to investigate the effect of changing the plantarflexion resistive moment of an articulated ankle-foot orthosis on ankle and knee joint angles and moments in patients post stroke. Methods Gait analysis was performed on 10 subjects post stroke under four different plantarflexion resistive moment conditions using a newly designed articulated ankle-foot orthosis. Data were recorded using a Bertec split-belt instrumented treadmill in a 3-dimensional motion analysis laboratory. Findings The ankle and knee sagittal joint angles and moments were significantly affected by the amount of plantarflexion resistive moment of the ankle-foot orthosis. Increasing the plantarflexion resistive moment of the ankle-foot orthosis induced significant decreases both in the peak ankle plantarflexion angle (P<0.01) and the peak knee extension angle (P<0.05). Also, the increase induced significant increases in the internal dorsiflexion moment of the ankle joint (P<0.01) and significantly decreased the internal flexion moment of the knee joint (P<0.01). Interpretation These results suggest an important link between the kinematic/kinetic parameters of the lower-limb joints and the plantarflexion resistive moment of an articulated ankle-foot orthosis. A future study should be performed to clarify their relationship further so that the practitioners may be able to use these parameters as objective data to determine an optimal plantarflexion resistive moment of an articulated ankle-foot orthosis for improved orthotic care in individual patients. PMID:26149007

The effect of changing plantarflexion resistive moment of an articulated ankle-foot orthosis on ankle and knee joint angles and moments while walking in patients post stroke.

PubMed

Kobayashi, Toshiki; Singer, Madeline L; Orendurff, Michael S; Gao, Fan; Daly, Wayne K; Foreman, K Bo

2015-10-01

The adjustment of plantarflexion resistive moment of an articulated ankle-foot orthosis is considered important in patients post stroke, but the evidence is still limited. Therefore, the aim of this study was to investigate the effect of changing the plantarflexion resistive moment of an articulated ankle-foot orthosis on ankle and knee joint angles and moments in patients post stroke. Gait analysis was performed on 10 subjects post stroke under four different plantarflexion resistive moment conditions using a newly designed articulated ankle-foot orthosis. Data were recorded using a Bertec split-belt instrumented treadmill in a 3-dimensional motion analysis laboratory. The ankle and knee sagittal joint angles and moments were significantly affected by the amount of plantarflexion resistive moment of the ankle-foot orthosis. Increasing the plantarflexion resistive moment of the ankle-foot orthosis induced significant decreases both in the peak ankle plantarflexion angle (P<0.01) and the peak knee extension angle (P<0.05). Also, the increase induced significant increases in the internal dorsiflexion moment of the ankle joint (P<0.01) and significantly decreased the internal flexion moment of the knee joint (P<0.01). These results suggest an important link between the kinematic/kinetic parameters of the lower-limb joints and the plantarflexion resistive moment of an articulated ankle-foot orthosis. A future study should be performed to clarify their relationship further so that the practitioners may be able to use these parameters as objective data to determine an optimal plantarflexion resistive moment of an articulated ankle-foot orthosis for improved orthotic care in individual patients. Copyright © 2015 Elsevier Ltd. All rights reserved.

MRI evaluation of anterolateral soft tissue impingement of the ankle.

PubMed

Ferkel, Richard D; Tyorkin, Max; Applegate, Gregory R; Heinen, Gregory T

2010-08-01

The usefulness of magnetic resonance imaging (MRI) has been questioned in evaluating patients with chronic ankle sprain pain. The purpose of this study was to determine the effectiveness and reliability of routine MR imaging in the diagnosis of anterolateral soft tissue impingement. Inclusion criteria required that the MR examinations be performed by the same musculoskeletal radiologist after the most recent scanner upgrade and using a dedicated ankle/hindfoot coil. The surgical and MRI reports of 24 patients who had an arthroscopic diagnosis of anterolateral soft tissue impingement of the ankle were tabulated and categorized. Unlike previous studies, sagittal T1 and Short Tau Inversion Recovery (STIR) images were used primarily in the diagnosis of these lesions. Using this technique, we report a 78.9% accuracy in diagnosis, a sensitivity of 83.3% and a specificity of 78.6%. Fifty-eight percent of patients had an associated diagnosis, which in 33% of patients altered our surgical plan. Although not indicated in all cases of anterolateral ankle impingement, we advocate the use of MR imaging in complicated clinical presentations where the exclusion of additional pathology in the ankle or subtalar joint, and the confirmation of anterolateral soft tissue impingement would be beneficial.

Reliable sagittal plane kinematic gait assessments are feasible using low-cost webcam technology.

PubMed

Saner, Robert J; Washabaugh, Edward P; Krishnan, Chandramouli

2017-07-01

Three-dimensional (3-D) motion capture systems are commonly used for gait analysis because they provide reliable and accurate measurements. However, the downside of this approach is that it is expensive and requires technical expertise; thus making it less feasible in the clinic. To address this limitation, we recently developed and validated (using a high-precision walking robot) a low-cost, two-dimensional (2-D) real-time motion tracking approach using a simple webcam and LabVIEW Vision Assistant. The purpose of this study was to establish the repeatability and minimal detectable change values of hip and knee sagittal plane gait kinematics recorded using this system. Twenty-one healthy subjects underwent two kinematic assessments while walking on a treadmill at a range of gait velocities. Intraclass correlation coefficients (ICC) and minimal detectable change (MDC) values were calculated for commonly used hip and knee kinematic parameters to demonstrate the reliability of the system. Additionally, Bland-Altman plots were generated to examine the agreement between the measurements recorded on two different days. The system demonstrated good to excellent reliability (ICC>0.75) for all the gait parameters tested on this study. The MDC values were typically low (<5°) for most of the parameters. The Bland-Altman plots indicated that there was no systematic error or bias in kinematic measurements and showed good agreement between measurements obtained on two different days. These results indicate that kinematic gait assessments using webcam technology can be reliably used for clinical and research purposes. Copyright © 2017 Elsevier B.V. All rights reserved.

The effect of ankle-foot orthosis plantarflexion stiffness on ankle and knee joint kinematics and kinetics during first and second rockers of gait in individuals with stroke

PubMed Central

Singer, Madeline L.; Kobayashi, Toshiki; Lincoln, Lucas S.; Orendurff, Michael S.; Foreman, K. Bo

2014-01-01

Background Stiffness of an ankle-foot orthosis plays an important role in improving gait in patients with a history of stroke. To address this, the aim of this case series study was to determine the effect of increasing plantarflexion stiffness of an ankle-foot orthosis on the sagittal ankle and knee joint angle and moment during the first and second rockers of gait. Methods Gait data were collected in 5 subjects with stroke at a self-selected walking speed under two plantarflexion stiffness conditions (0.4 Nm/deg and 1.3 Nm/deg) using a stiffness-adjustable experimental ankle-foot orthosis on a Bertec split-belt fully instrumented treadmill in a 3-dimensional motion analysis laboratory. Findings By increasing the plantarflexion stiffness of the ankle-foot orthosis, peak plantarfexion angle of the ankle was reduced and peak dorsiflexion moment was generally increased in the first rocker as hypothesized. Two subjects demonstrated increases in both peak knee flexion angle and peak knee extension moment in the second rocker as hypothesized. The two subjects exhibited minimum contractility during active plantarflexion, while the other three subjects could actively plantarflex their ankle joint. Interpretation It was suggested that those with the decreased ability to actively plantarflex their ankle could not overcome excessive plantarflexion stiffness at initial contact of gait, and as a result exhibited compensation strategies at the knee joint. Providing excessively stiff ankle-foot orthoses might put added stress on the extensor muscles of the knee joint, potentially creating fatigue and future pathologies in some patients with stroke. PMID:25241248

Effect of alignment changes on sagittal and coronal socket reaction moment interactions in transtibial prostheses.

PubMed

Kobayashi, Toshiki; Orendurff, Michael S; Zhang, Ming; Boone, David A

2013-04-26

Alignment is important for comfortable and stable gait of lower-limb prosthesis users. The magnitude of socket reaction moments in the multiple planes acting simultaneously upon the residual limb may be related to perception of comfort in individuals using prostheses through socket interface pressures. The aim of this study was to investigate the effect of prosthetic alignment changes on sagittal and coronal socket reaction moment interactions (moment-moment curves) and to characterize the curves in 11 individuals with transtibial amputation using novel moment-moment interaction parameters measured by plotting sagittal socket reaction moments versus coronal ones under various alignment conditions. A custom instrumented prosthesis alignment component was used to measure socket reaction moments during walking. Prosthetic alignment was tuned to a nominally aligned condition by a prosthetist, and from this position, angular (3° and 6° of flexion, extension, abduction or adduction of the socket) and translational (5mm and 10mm of anterior, posterior, medial or lateral translation of the socket) alignment changes were performed in either the sagittal or the coronal plane in a randomized manner. A total of 17 alignment conditions were tested. Coronal angulation and translation alignment changes demonstrated similar consistent changes in the moment-moment curves. Sagittal alignment changes demonstrated more complex changes compared to the coronal alignment changes. Effect of sagittal angulations and translations on the moment-moment curves was different during 2nd rocker (mid-stance) with extension malalignment appearing to cause medio-lateral instability. Presentation of coronal and sagittal socket reaction moment interactions may provide useful visual information for prosthetists to understand the biomechanical effects of malalignment of transtibial prostheses. Copyright © 2013 Elsevier Ltd. All rights reserved.

Coordination and Symmetry Patterns During the Drop Vertical Jump in People With Chronic Ankle Instability and Lateral Ankle Sprain Copers.

PubMed

Doherty, Cailbhe; Bleakley, Chris; Hertel, Jay; Caulfield, Brian; Ryan, John; Sweeney, Kevin; Patterson, Matthew R; Delahunt, Eamonn

2016-08-01

The drop vertical jump (DVJ) task has previously been used to identify movement patterns associated with a number of injury types. However, no current research exists evaluating people with chronic ankle instability (CAI) compared with people coping with lateral ankle sprain (LAS) (referred to as "LAS copers") during this task. The aim of this study was to identify the coping movement and motor control patterns of LAS copers in comparison with individuals with CAI during the DVJ task. This was a case-control study. Seventy individuals were recruited at convenience within 2-weeks of sustaining a first-time acute LAS injury. One year following recruitment, these individuals were stratified into 2 groups: 28 with CAI and 42 LAS copers. They attended the testing laboratory to complete a DVJ task. Three-dimensional kinematic and sagittal-plane kinetic profiles were plotted for the lower extremity joints of both limbs for the drop jump phase (phase 1) and drop landing phase (phase 2) of the DVJ. The rate of impact modulation relative to body weight during both phases of the DVJ also was determined. Compared with LAS copers, participants with CAI displayed significant increases in hip flexion on their "involved" limb during phase 1 of the DVJ (23° vs 18°) and bilaterally during phase 2 (15° vs 10°). These movement patterns coincided with altered moment-of-force patterns at the hip on the "uninvolved" limb. It is unknown whether these movement and motor control patterns preceded or occurred as a result of the initial LAS injury. Participants with CAI displayed hip-centered changes in movement and motor control patterns during a DVJ task compared with LAS copers. The findings of this study may give an indication of the coping mechanism underlying outcome following initial LAS injury. © 2016 American Physical Therapy Association.

Can Axial-Based Nodal Size Criteria Be Used in Other Imaging Planes to Accurately Determine “Enlarged” Head and Neck Lymph Nodes?

PubMed Central

Bartlett, Eric S.; Walters, Thomas D.; Yu, Eugene

2013-01-01

Objective. We evaluate if axial-based lymph node size criteria can be applied to coronal and sagittal planes. Methods. Fifty pretreatment computed tomographic (CT) neck exams were evaluated in patients with head and neck squamous cell carcinoma (SCCa) and neck lymphadenopathy. Axial-based size criteria were applied to all 3 imaging planes, measured, and classified as “enlarged” if equal to or exceeding size criteria. Results. 222 lymph nodes were “enlarged” in one imaging plane; however, 53.2% (118/222) of these were “enlarged” in all 3 planes. Classification concordance between axial versus coronal/sagittal planes was poor (kappa = −0.09 and −0.07, resp., P < 0.05). The McNemar test showed systematic misclassification when comparing axial versus coronal (P < 0.001) and axial versus sagittal (P < 0.001) planes. Conclusion. Classification of “enlarged” lymph nodes differs between axial versus coronal/sagittal imaging planes when axial-based nodal size criteria are applied independently to all three imaging planes, and exclusively used without other morphologic nodal data. PMID:23984099

Periprosthetic osteolysis after AES total ankle replacement: Conventional radiography versus CT-scan.

PubMed

Viste, Anthony; Al Zahrani, Nader; Brito, Nuno; Lienhart, Christophe; Fessy, Michel Henri; Besse, Jean-Luc

2015-09-01

The aim of this study was to compare conventional X-rays and CT-scan in detecting peri-prosthetic osteolytic lesions, a major concern after total ankle replacement (TAR). We prospectively assessed 50 patients (mean age 56 years), consecutively operated on by the same senior surgeon, between 2003 and 2006 and with a mean follow-up period of 4 years (range, 2-6.2). The component used was AES total ankle replacement. The etiologies for total ankle arthroplasty were: posttraumatic in 50%, osteoarthritis secondary to instability in 36%. Plain radiographs were analyzed by 4 independent observers, using a 10-zone protocol (location) and 5 size categories. At 4-year follow-up, all patients had been CT-scan assessed with the same protocol by 2 independent observers. Plain radiographs showed dramatic progression of severe periprosthetic lyses (>10mm): from 14% to 36% of interface cysts for the tibial component respectively at 2 and 4-year follow-up and from 4% to 30% for the talar implant. The talar component was more accurately assessed by CT-scan (mean frontal and sagittal talar lesion: from 270 mm2 to 288 mm2 for CT-scan versus 133 mm2 to 174 mm2 for X-rays). For tibial cysts, axial views showed larger lesions (313 mm2 than frontal (194 mm2) or sagittal (213.5 mm2) views. At 4-year follow-up, 24% of patients had revision with curetage or arthrodesis, and at 7 years follow-up 38% were revised. These results are similar to recent AES series, justifying withdrawal of this device. CT-scan was more accurate than X-rays for detecting and quantifying periprosthetic osteolysis. We recommend a yearly radiological control and CT-scan in case of lesion on X-rays. Copyright © 2014 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

One-degree-of-freedom spherical model for the passive motion of the human ankle joint.

PubMed

Sancisi, Nicola; Baldisserri, Benedetta; Parenti-Castelli, Vincenzo; Belvedere, Claudio; Leardini, Alberto

2014-04-01

Mathematical modelling of mobility at the human ankle joint is essential for prosthetics and orthotic design. The scope of this study is to show that the ankle joint passive motion can be represented by a one-degree-of-freedom spherical motion. Moreover, this motion is modelled by a one-degree-of-freedom spherical parallel mechanism model, and the optimal pivot-point position is determined. Passive motion and anatomical data were taken from in vitro experiments in nine lower limb specimens. For each of these, a spherical mechanism, including the tibiofibular and talocalcaneal segments connected by a spherical pair and by the calcaneofibular and tibiocalcaneal ligament links, was defined from the corresponding experimental kinematics and geometry. An iterative procedure was used to optimize the geometry of the model, able to predict original experimental motion. The results of the simulations showed a good replication of the original natural motion, despite the numerous model assumptions and simplifications, with mean differences between experiments and predictions smaller than 1.3 mm (average 0.33 mm) for the three joint position components and smaller than 0.7° (average 0.32°) for the two out-of-sagittal plane rotations, once plotted versus the full flexion arc. The relevant pivot-point position after model optimization was found within the tibial mortise, but not exactly in a central location. The present combined experimental and modelling analysis of passive motion at the human ankle joint shows that a one degree-of-freedom spherical mechanism predicts well what is observed in real joints, although its computational complexity is comparable to the standard hinge joint model.

Task-level strategies for human sagittal-plane running maneuvers are consistent with robotic control policies.

PubMed

Qiao, Mu; Jindrich, Devin L

2012-01-01

The strategies that humans use to control unsteady locomotion are not well understood. A "spring-mass" template comprised of a point mass bouncing on a sprung leg can approximate both center of mass movements and ground reaction forces during running in humans and other animals. Legged robots that operate as bouncing, "spring-mass" systems can maintain stable motion using relatively simple, distributed feedback rules. We tested whether the changes to sagittal-plane movements during five running tasks involving active changes to running height, speed, and orientation were consistent with the rules used by bouncing robots to maintain stability. Changes to running height were associated with changes to leg force but not stance duration. To change speed, humans primarily used a "pogo stick" strategy, where speed changes were associated with adjustments to fore-aft foot placement, and not a "unicycle" strategy involving systematic changes to stance leg hip moment. However, hip moments were related to changes to body orientation and angular speed. Hip moments could be described with first order proportional-derivative relationship to trunk pitch. Overall, the task-level strategies used for body control in humans were consistent with the strategies employed by bouncing robots. Identification of these behavioral strategies could lead to a better understanding of the sensorimotor mechanisms that allow for effective unsteady locomotion.

Task-Level Strategies for Human Sagittal-Plane Running Maneuvers Are Consistent with Robotic Control Policies

PubMed Central

Qiao, Mu; Jindrich, Devin L.

2012-01-01

The strategies that humans use to control unsteady locomotion are not well understood. A “spring-mass” template comprised of a point mass bouncing on a sprung leg can approximate both center of mass movements and ground reaction forces during running in humans and other animals. Legged robots that operate as bouncing, “spring-mass” systems can maintain stable motion using relatively simple, distributed feedback rules. We tested whether the changes to sagittal-plane movements during five running tasks involving active changes to running height, speed, and orientation were consistent with the rules used by bouncing robots to maintain stability. Changes to running height were associated with changes to leg force but not stance duration. To change speed, humans primarily used a “pogo stick” strategy, where speed changes were associated with adjustments to fore-aft foot placement, and not a “unicycle” strategy involving systematic changes to stance leg hip moment. However, hip moments were related to changes to body orientation and angular speed. Hip moments could be described with first order proportional-derivative relationship to trunk pitch. Overall, the task-level strategies used for body control in humans were consistent with the strategies employed by bouncing robots. Identification of these behavioral strategies could lead to a better understanding of the sensorimotor mechanisms that allow for effective unsteady locomotion. PMID:23284804

Validation, repeatability and reproducibility of a noninvasive instrument for measuring thoracic and lumbar curvature of the spine in the sagittal plane.

PubMed

Chaise, Fabiana O; Candotti, Cláudia T; Torre, Marcelo L; Furlanetto, Tássia S; Pelinson, Patricia P T; Loss, Jefferson F

2011-01-01

The need for early identification of postural abnormalities without exposing patients to constant radiation has stimulated the development of instruments aiming to measure the spinal curvatures. To verify the validity, repeatability and reproducibility of angular measures of sagittal curvatures of the spine obtained using an adapted arcometer, by comparing them with Cobb angles of the respective curvatures obtained by using X-rays. 52 participants were submitted to two procedures designed to evaluate the thoracic and lumbar curvatures: (1) X-ray examination from which the Cobb angles (CA) of both curvatures were obtained, and (2) measuring the angles with the arcometer (AA). Two evaluators collected the data using the arcometer, with the rods placed at T1, T12, L1 and L5 spinous processes levels in a way as to permit linear measurements which, with aid of trigonometry, supplied the AA. There was a very strong and significant correlation between AA and CA (r=0.94; p<0.01), with no-significant difference (p=0.32), for the thoracic curvature. There was a strong and significant correlation for the lumbar curvature (r=0.71; p<0.01) between AA and CA, with no-significant difference (p=0.30). There is a very strong correlation between intra-evaluator and inter-evaluator AA. It was possible to quantify reliably the thoracic and lumbar curvatures with the arcometer and it can thus be considered valid and reliable and for use in evaluating spinal curvatures in the sagittal plane.

Effect of the sagittal ankle angle at initial contact on energy dissipation in the lower extremity joints during a single-leg landing.

PubMed

Lee, Jinkyu; Song, Yongnam; Shin, Choongsoo S

2018-05-01

During landing, the ankle angle at initial contact (IC) exhibits relatively wide individual variation compared to the knee and hip angles. However, little is known about the effect of different IC ankle angles on energy dissipation. The purpose of this study was to investigate the relationship between individual ankle angles at IC and energy dissipation in the lower extremity joints. Twenty-seven adults performed single-leg landings from a 0.3-m height. Kinetics and kinematics of the lower extremity joints were measured. The relationship between ankle angles at IC and negative work, range of motion, the time to peak ground reaction force, and peak loading rate were analyzed. The ankle angle at IC was positively correlated with ankle negative work (r = 0.80, R 2  = 0.64, p < 0.001) and the contribution of the ankle to total (ankle, knee and hip joint) negative work (r = 0.84, R 2  = 0.70, p < 0.001), but the ankle angle was negatively correlated with hip negative work (r = -0.46, R 2  = 0.21, p = 0.01) and the contribution of the hip to total negative work (r = -0.61, R 2  = 0.37, p < 0.001). The knee negative work and the contribution of the knee to total negative work were not correlated with the ankle angle at IC. The ankle angle at IC was positively correlated with total negative work (r = 0.50, R 2  = 0.25, p < 0.01) and negatively correlated with the peak loading rate (r = -0.76, R 2  = 0.57, p < 0.001). These results indicated that landing mechanics changed as the ankle angle at IC increased, such that the ankle energy dissipation increased and redistributed the energy dissipation in the ankle and hip joints. Further, these results suggest that increased ankle energy dissipation with a higher IC plantar flexion angle may be a potential landing technique for reducing the risk of injury to the anterior cruciate ligament and hip musculature. Copyright © 2018 Elsevier B.V. All rights reserved.

Occlusal plane rotation: aesthetic enhancement in mandibular micrognathia.

PubMed

Rosen, H M

1993-06-01

Patients afflicted with extreme degrees of mandibular micrognathia typically have vertically deficient rami as well as sagittally deficient mandibular bodies. This results in deficient posterior facial height, an obtuse gonial angle, excessively steep occlusal and mandibular planes, and a compensatory increase in anterior facial height. The entire maxillomandibular complex is overrotated in a clockwise direction. Standard orthognathic surgical correction fails to address this rotational deformity. As a consequence, the achieved projection of the lower face is inadequate, posterior facial height is further reduced, and occlusal and mandibular planes remain steep. Eleven patients with severe mandibular micrognathia underwent a surgical correction involving occlusal plane rotation to its normal orientation relative to Frankfort horizontal. This was accomplished by Le Fort I osteotomy to shorten the anterior maxilla (creating open bites in seven patients and making preexisting open bites worse in four patients) and sagittal split ramus osteotomies to advance and rotate the mandibular body counterclockwise, thus closing the surgically produced open bite. Counterclockwise rotation of the mandible afforded significantly greater sagittal displacement at the B point (mean 17 mm) than at the first molar (mean 10 mm) and produced adequate degrees of projection of the lower face when accompanied by a modest sliding genioplasty (mean 6.9 mm). Total advancement at the pogonion was a mean of 25.2 mm. In addition, posterior facial height was preserved, and mandibular and occlusal planes were normalized to mean angles of 27 and 10 degrees, respectively. At follow-up, which ranged from 9 to 24 months with a mean of 14.1 months, the mean sagittal relapse at the B point was 1.9 mm. Although heretofore considered unstable and therefore not clinically accepted, maxillomandibular counterclockwise rotation to normalize the occlusal plane rotational deformity provides stable, aesthetically

Standardized way for imaging of the sagittal spinal balance.

PubMed

Morvan, Gérard; Mathieu, Philippe; Vuillemin, Valérie; Guerini, Henri; Bossard, Philippe; Zeitoun, Frédéric; Wybier, Marc

2011-09-01

Nowadays, conventional or digitalized teleradiography remains the most commonly used tool for the study of the sagittal balance, sometimes with secondary digitalization. The irradiation given by this technique is important and the photographic results are often poor. Some radiographic tables allow the realization of digitalized spinal radiographs by simultaneous translation of X-ray tube and receptor. EOS system is a new, very low dose system which gives good quality images, permits a simultaneous acquisition of upright frontal and sagittal views, is able to cover in the same time the spine and the lower limbs and study the axial plane on 3D envelope reconstructions. In the future, this low dose system should take a great place in the study of the pelvispinal balance. On the lateral view, several pelvic (incidence, pelvic tilt, sacral slope) and spinal (lumbar lordosis, thoracic kyphosis, Th9 sagittal offset, C7 plumb line) parameters are drawn to define the pelvispinal balance. All are interdependent. Pelvic incidence is an individual anatomic characteristic that corresponds to the "thickness" of the pelvis and governs the spinal balance. Pelvis and spine, in a harmonious whole, can be compared to an accordion, more or less compressed or stretched.

Redistribution of Mechanical Work at the Knee and Ankle Joints During Fast Running in Minimalist Shoes.

PubMed

Fuller, Joel T; Buckley, Jonathan D; Tsiros, Margarita D; Brown, Nicholas A T; Thewlis, Dominic

2016-10-01

Minimalist shoes have been suggested as a way to alter running biomechanics to improve running performance and reduce injuries. However, to date, researchers have only considered the effect of minimalist shoes at slow running speeds. To determine if runners change foot-strike pattern and alter the distribution of mechanical work at the knee and ankle joints when running at a fast speed in minimalist shoes compared with conventional running shoes. Crossover study. Research laboratory. Twenty-six trained runners (age = 30.0 ± 7.9 years [age range, 18-40 years], height = 1.79 ± 0.06 m, mass = 75.3 ± 8.2 kg, weekly training distance = 27 ± 15 km) who ran with a habitual rearfoot foot-strike pattern and had no experience running in minimalist shoes. Participants completed overground running trials at 18 km/h in minimalist and conventional shoes. Sagittal-plane kinematics and joint work at the knee and ankle joints were computed using 3-dimensional kinematic and ground reaction force data. Foot-strike pattern was classified as rearfoot, midfoot, or forefoot strike based on strike index and ankle angle at initial contact. We observed no difference in foot-strike classification between shoes (χ 2 1 = 2.29, P = .13). Ankle angle at initial contact was less (2.46° versus 7.43°; t 25 = 3.34, P = .003) and strike index was greater (35.97% versus 29.04%; t 25 = 2.38, P = .03) when running in minimalist shoes compared with conventional shoes. We observed greater negative (52.87 J versus 42.46 J; t 24 = 2.29, P = .03) and positive work (68.91 J versus 59.08 J; t 24 = 2.65, P = .01) at the ankle but less negative (59.01 J versus 67.02 J; t 24 = 2.25, P = .03) and positive work (40.37 J versus 47.09 J; t 24 = 2.11, P = .046) at the knee with minimalist shoes compared with conventional shoes. Running in minimalist shoes at a fast speed caused a redistribution of work from the knee to the ankle joint. This finding suggests that runners changing from conventional to minimalist

Redistribution of Mechanical Work at the Knee and Ankle Joints During Fast Running in Minimalist Shoes

PubMed Central

Fuller, Joel T.; Buckley, Jonathan D.; Tsiros, Margarita D.; Brown, Nicholas A. T.; Thewlis, Dominic

2016-01-01

Context: Minimalist shoes have been suggested as a way to alter running biomechanics to improve running performance and reduce injuries. However, to date, researchers have only considered the effect of minimalist shoes at slow running speeds. Objective: To determine if runners change foot-strike pattern and alter the distribution of mechanical work at the knee and ankle joints when running at a fast speed in minimalist shoes compared with conventional running shoes. Design: Crossover study. Setting: Research laboratory. Patients or Other Participants: Twenty-six trained runners (age = 30.0 ± 7.9 years [age range, 18−40 years], height = 1.79 ± 0.06 m, mass = 75.3 ± 8.2 kg, weekly training distance = 27 ± 15 km) who ran with a habitual rearfoot foot-strike pattern and had no experience running in minimalist shoes. Intervention(s): Participants completed overground running trials at 18 km/h in minimalist and conventional shoes. Main Outcome Measure(s): Sagittal-plane kinematics and joint work at the knee and ankle joints were computed using 3-dimensional kinematic and ground reaction force data. Foot-strike pattern was classified as rearfoot, midfoot, or forefoot strike based on strike index and ankle angle at initial contact. Results: We observed no difference in foot-strike classification between shoes (χ21 = 2.29, P = .13). Ankle angle at initial contact was less (2.46° versus 7.43°; t25 = 3.34, P = .003) and strike index was greater (35.97% versus 29.04%; t25 = 2.38, P = .03) when running in minimalist shoes compared with conventional shoes. We observed greater negative (52.87 J versus 42.46 J; t24 = 2.29, P = .03) and positive work (68.91 J versus 59.08 J; t24 = 2.65, P = .01) at the ankle but less negative (59.01 J versus 67.02 J; t24 = 2.25, P = .03) and positive work (40.37 J versus 47.09 J; t24 = 2.11, P = .046) at the knee with minimalist shoes compared with conventional shoes. Conclusions: Running in minimalist shoes at a fast speed caused a

Determination of a sagittal plane axis of rotation for a dynamic office chair.

PubMed

Bauer, C M; Rast, F M; Böck, C; Kuster, R P; Baumgartner, D

2018-10-01

This study investigated the location of the axis of rotation in sagittal plane movement of the spine in a free sitting condition to adjust the kinematics of a mobile seat for a dynamic chair. Dynamic office chairs are designed to avoid continuous isometric muscle activity, and to facilitate increased mobility of the back during sitting. However, these chairs incorporate increased upper body movement which could distract office workers from the performance of their tasks. A chair with an axis of rotation above the seat would facilitate a stable upper back during movements of the lower back. The selection of a natural kinematic pattern is of high importance in order to match the properties of the spine. Twenty-one participants performed four cycles of flexion and extension of the spine during an upper arm hang on parallel bars. The location of the axis of rotation relative to the seat was estimated using infrared cameras and reflective skin markers. The median axis of rotation across all participants was located 36 cm above the seat for the complete movement and 39 cm for both the flexion and extension phases, each with an interquartile range of 20 cm. There was no significant effect of the movement direction on the location of the axis of rotation and only a weak, non-significant correlation between body height and the location of the axis of rotation. Individual movement patterns explained the majority of the variance. The axis of rotation for a spinal flexion/extension movement is located above the seat. The recommended radius for a guide rail of a mobile seat is between 36 cm and 39 cm. Copyright © 2018 Elsevier Ltd. All rights reserved.

CHANGES IN LOWER EXTREMITY MOVEMENT AND POWER ABSORPTION DURING FOREFOOT STRIKING AND BAREFOOT RUNNING

PubMed Central

Green, Douglas H.; Wurzinger, Brian

2012-01-01

Purpose/Background: Both forefoot strike shod (FFS) and barefoot (BF) running styles result in different mechanics when compared to rearfoot strike (RFS) shod running. Additionally, running mechanics of FFS and BF running are similar to one another. Comparing the mechanical changes occurring in each of these patterns is necessary to understand potential benefits and risks of these running styles. The authors hypothesized that FFS and BF conditions would result in increased sagittal plane joint angles at initial contact and that FFS and BF conditions would demonstrate a shift in sagittal plane joint power from the knee to the ankle when compared to the RFS condition. Finally, total lower extremity power absorption will be least in BF and greatest in the RFS shod condition. Methods: The study included 10 male and 10 female RFS runners who completed 3‐dimensional running analysis in 3 conditions: shod with RFS, shod with FFS, and BF. Variables were the angles of plantarflexion, knee flexion, and hip flexion at initial contact and peak sagittal plane joint power at the hip, knee, and ankle during stance phase. Results: Running with a FFS pattern and BF resulted in significantly greater plantarflexion and significantly less negative knee power (absorption) when compared to shod RFS condition. FFS condition runners landed in the most plantarflexion and demonstrated the most peak ankle power absorption and lowest knee power absorption between the 3 conditions. BF and FFS conditions demonstrated decreased total lower extremity power absorption compared to the shod RFS condition but did not differ from one another. Conclusions: BF and FFS running result in reduced total lower extremity power, hip power and knee power and a shift of power absorption from the knee to the ankle. Clinical Relevance: Alterations associated with BF running patterns are present in a FFS pattern when wearing shoes. Additionally, both patterns result in increased demand at the foot and ankle as

A clinico-radiographic analysis of sagittal condylar guidance determined by protrusive interocclusal registration and panoramic radiographic images in humans

PubMed Central

Prasad, Krishna D.; Shah, Namrata; Hegde, Chethan

2012-01-01

Purpose: To evaluate the correlation between sagittal condylar guidance obtained by protrusive interocclusal records and panoramic radiograph tracing methods in human dentulous subjects. Materials and Methods: The sagittal condylar guidance was determined in 75 dentulous subjects by protrusive interocclusal records using Aluwax through a face bow transfer (HANAU™ Spring Bow, Whip Mix Corporation, USA) to a semi-adjustable articulator (HANAU™ Wide-Vue Articulator, Whip Mix Corporation, USA). In the same subjects, the sagittal outline of the articular eminence and glenoid fossa was traced in panoramic radiographs. The sagittal condylar path inclination was constructed by joining the heights of curvature in the glenoid fossa and the corresponding articular eminence. This was then related to the constructed Frankfurt's horizontal plane to determine the radiographic angle of sagittal condylar guidance. Results: A strong positive correlation existed between right and left condylar guidance by the protrusive interocclusal method (P 0.000) and similarly by the radiographic method (P 0.013). The mean difference between the condylar guidance obtained using both methods were 1.97° for the right side and 3.18° for the left side. This difference between the values by the two methods was found to be highly significant for the right (P 0.003) and left side (P 0.000), respectively. The sagittal condylar guidance obtained from both methods showed a significant positive correlation on right (P 0.000) and left side (P 0.015), respectively. Conclusion: Panoramic radiographic tracings of the sagittal condylar path guidance may be made relative to the Frankfurt's horizontal reference plane and the resulting condylar guidance angles used to set the condylar guide settings of semi-adjustable articulators. PMID:23633793

Relationships between the center of pressure and the movements of the ankle and knee joints during the stance phase in patients with severe medial knee osteoarthritis.

PubMed

Fukaya, Takashi; Mutsuzaki, Hirotaka; Okubo, Tomoyuki; Mori, Koichi; Wadano, Yasuyoshi

2016-08-01

The knee joint movement during the stance phase is affected by altered ankle movement and the center of pressure (COP). However the relationships between changes in the center of pressure (COP) and the altered kinematics and kinetics of the ankle and knee joints in patients with osteoarthritis (OA) of the knee are not well understood. The purpose of this study was to determine the relationships between changes in the COP and the altered kinematic and kinetic variables in ankle and knee joints during the stance phase in patients with medial knee OA. Fourteen patients with knee OA (21 knees) and healthy subjects were assessed by gait analysis using an eight-camera motion analysis system to record forward and lateral shifts in the COP and the angle and net internal moments of the knee and ankle joint. Spearman rank-correlation coefficients were used to determine the relationship between these results. In knees with medial OA, lateral shifts in the COP were correlated with knee flexion angle. Lateral shifts in the COP were correlated with the second peak of the knee extensor moment and correlated with the knee abductor moment. In patients with medial knee OA, lateral shifts in the COP were negatively correlated with the kinematic and kinetic variables in the sagittal plane of the knee joints. Controlling such lateral shifts in the COP may thus be an effective intervention for mechanical loads on the knee during the stance phase in patients with knee OA. Copyright © 2016 Elsevier B.V. All rights reserved.

Morphological characteristics of the posterior malleolar fragment according to ankle fracture patterns: a computed tomography-based study.

PubMed

Yi, Young; Chun, Dong-Il; Won, Sung Hun; Park, Suyeon; Lee, Sanghyeon; Cho, Jaeho

2018-02-13

The posterior malleolar fragment (PMF) of an ankle fracture can have various shapes depending on the injury mechanism. The purpose of this study was to evaluate the morphological characteristics of the PMF according to the ankle fracture pattern described in the Lauge-Hansen classification by using computed tomography (CT) images. We retrospectively analyzed CT data of 107 patients (107 ankles) who underwent surgery for trimalleolar fracture from January 2012 to December 2014. The patients were divided into two groups: 76 ankles in the supination-external rotation (SER) stage IV group and 31 ankles in the pronation-external rotation (PER) stage IV group. The PMF type of the two groups was assessed using the Haraguchi and Jan Bartonicek classification. The cross angle (α), fragment length ratio (FLR), fragment area ratio (FAR), sagittal angle (θ), and fragment height (FH) were measured to assess the morphological characteristics of the PMF. The PMF in the SER group mainly had a posterolateral shape, whereas that in the PER group mainly had a posteromedial two-part shape or a large posterolateral triangular shape (P = 0.02). The average cross angle was not significantly different between the two groups (SER group = 19.4°, PER group = 17.6°). The mean FLR and FH were significantly larger in the PER group than in the SER group (P = 0.024, P = 0.006). The mean fragment sagittal angle in the PER group was significantly smaller than that in the SER group (P = 0.017). With regard to the articular involvement, volume, and vertical nature, the SER-type fracture tends to have a smaller fragment due to the rotational force, whereas the PER-type fracture tends to have a larger fragment due to the combination of rotational and axial forces.

The effect of external ankle support on knee and ankle joint movement and loading in netball players.

PubMed

Vanwanseele, Benedicte; Stuelcken, Max; Greene, Andrew; Smith, Richard

2014-09-01

External ankle support has been successfully used to prevent ankle sprains. However, some recent studies have indicated that reducing ankle range of motion can place larger loads on the knee. The aim of this study was to investigate the effect of external ankle support (braces and high-top shoes) on the ankle and knee joint loading during a netball specific landing task. A repeated measure design. High performance netball players with no previously diagnosed severe ankle or knee injury (n=11) were recruited from NSW Institute of Sport netball programme. The kinematic and kinetic data were collected simultaneously using a 3-D Motion Analysis System and one Kistler force plate to measure ground reaction forces. Players performed a single leg landing whilst receiving a pass while wearing a standard netball shoe, the same shoe with a lace-up brace and a high-top shoe. Only the brace condition significantly reduced the ankle range of motion in the frontal plane (in/eversion) by 3.95 ± 3.74 degrees compared to the standard condition. No changes were found for the knee joint loading in the brace condition. The high-top shoes acted to increase the peak knee internal rotation moment by 15%. Both the brace and high-top conditions brought about increases in the peak ankle plantar flexion moment during the landing phase. Lace-up braces can be used by netball players to restrict ankle range of motion during a single leg landing while receiving a pass without increasing the load on the knee joint. Copyright © 2013 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Frontal plane landing mechanics in high-arched compared with low-arched female athletes.

PubMed

Powell, Douglas W; Hanson, Nicholas J; Long, Benjamin; Williams, D S Blaise

2012-09-01

To examine ground reaction forces (GRFs); frontal plane hip, knee, and ankle joint angles; and moments in high-arched (HA) and low-arched (LA) athletes during landing. Experimental study. Controlled research laboratory. Twenty healthy female recreational athletes (10 HA and 10 LA). Athletes performed 5 barefoot drop landings from a height of 30 cm. Frontal plane ankle, knee, and hip joint angles (in degrees) at initial contact, peak vertical GRF, and peak knee flexion; peak ankle, knee, and hip joint moments in the frontal plane. Vertical GRF profiles were similar between HA and LA athletes (P = 0.78). The HA athletes exhibited significantly smaller peak ankle inversion angles than the LA athletes (P = 0.01) at initial contact. At peak vertical GRF, HA athletes had significantly greater peak knee (P = 0.01) and hip abduction angles than LA athletes (P = 0.02). There were no significant differences between HA and LA athletes in peak joint moments (hip: P = 0.68; knee: P = 0.71; ankle: P = 0.15). These findings demonstrate that foot type is associated with altered landing mechanics, which may underlie lower extremity injuries. The ankle-driven strategy previously reported in female athletes suggests that foot function may have a greater relationship with lower extremity injury than that in male athletes. Future research should address the interaction of foot type and gender during landing tasks.

Kinetic and kinematic evaluation of the ankle joint after achilles tendon reconstruction with free semitendinosus tendon graft: preliminary results.

PubMed

Lins, Carolina; Ninomya, André Felipe; Bittar, Cintia Kelly; de Carvalho, Antônio Egydio; Cliquet, Alberto

2013-03-01

Chronic rupture of the Achilles tendon (AT) is a surgical challenge and has effects on the gait. The purpose of this study was to evaluate the kinetic and kinematic parameters of the ankle joint in patients with AT rupture operated using a free semitendinosus tendon graft. Thirteen patients were analyzed 6 and 12 months after surgery in a force platform, while the movements were recorded by six infrared cameras. The kinematic variables analyzed included speed, cadence, step length, percentage of stance phase, and range of movement (ROM) of the ankle joint in the sagittal and frontal planes. Kinetic data were obtained by joint movement in different phases of the gait cycle. Functional assessment was performed using the American Orthopaedic Foot and Ankle Society (AOFAS) score. The patients showed a significant increase (P = 0.0215) in AOFAS from 68.5 (±18.7) to 85.2 (±18.0). Speed, cadence, and length of step of the four groups (1A, 1B, 2A, 2B) were lower than the control group (group 3), and the percentage in stance phase was higher for the nonoperated foot 6-month group (1B) compared to the control group (group 3). For the kinematic data, the ROM of the ankle in stance phase increased from 6 to 12 months showing an effect of time between four groups (1A, 1B, 2A, 2B). During swing phase, the ankle ROM was lower in the operated side (effect of side, P = 0.0255) and groups 1A and 2A demonstrated statistical differences when compared with the control group (group 3) (P = 0.0240 and P = 0.0414, respectively). ROM of inversion and eversion presented effect of time among the same groups (P = 0.0059) cited before. There were no differences in kinetic data between groups. This study showed close proximity between the control group and the operated group. Furthermore, improvement was shown when comparing the 6 and 12 months postsurgery periods. The surgical procedure is therefore helpful for the patient and few changes were present in gait and ankle

Inter- and intraobserver repeatability of the Salford Gait Tool: an observation-based clinical gait assessment tool.

PubMed

Toro, Brigitte; Nester, Christopher J; Farren, Pauline C

2007-03-01

To evaluate the inter- and intraobserver repeatability of the Salford Gait Tool (SF-GT), a new observation-based gait assessment tool for evaluating sagittal plane cerebral palsy (CP) gait. Masked comparative evaluation. University in the United Kingdom. A convenience sample of 23 pediatric physical therapists with varying degrees of clinical experience recruited from the Greater Manchester area. Participants viewed videotapes of the sagittal plane gait of 13 children and used the SF-GT to analyze their 13 different gait styles on 2 occasions. Eleven children had hemiplegic, diplegic, or quadriplegic CP and 2 were neurologically intact. Inter- and intraobserver repeatability of hip, knee, and ankle joint positions at 6 different phases of the gait cycle. The SF-GT demonstrated good interobserver (77%) and intraobserver (75%) repeatability. We have established that the SF-GT is a repeatable clinical assessment tool with which to guide the diagnosis, treatment planning, and evaluation of interventions by pediatric physical therapists of sagittal plane gait deviations in CP.

Reliability and reproducibility analysis of the Cobb angle and assessing sagittal plane by computer-assisted and manual measurement tools.

PubMed

Wu, Weifei; Liang, Jie; Du, Yuanli; Tan, Xiaoyi; Xiang, Xuanping; Wang, Wanhong; Ru, Neng; Le, Jinbo

2014-02-06

Although many studies on reliability and reproducibility of measurement have been performed on coronal Cobb angle, few results about reliability and reproducibility are reported on sagittal alignment measurement including the pelvis. We usually use SurgimapSpine software to measure the Cobb angle in our studies; however, there are no reports till date on its reliability and reproducible measurements. Sixty-eight standard standing posteroanterior whole-spine radiographs were reviewed. Three examiners carried out the measurements independently under the settings of manual measurement on X-ray radiographies and SurgimapSpine software on the computer. Parameters measured included pelvic incidence, sacral slope, pelvic tilt, Lumbar lordosis (LL), thoracic kyphosis, and coronal Cobb angle. SPSS 16.0 software was used for statistical analyses. The means, standard deviations, intraclass and interclass correlation coefficient (ICC), and 95% confidence intervals (CI) were calculated. There was no notable difference between the two tools (P = 0.21) for the coronal Cobb angle. In the sagittal plane parameters, the ICC of intraobserver reliability for the manual measures varied from 0.65 (T2-T5 angle) to 0.95 (LL angle). Further, for SurgimapSpine tool, the ICC ranged from 0.75 to 0.98. No significant difference in intraobserver reliability was found between the two measurements (P > 0.05). As for the interobserver reliability, measurements with SurgimapSpine tool had better ICC (0.71 to 0.98 vs 0.59 to 0.96) and Pearson's coefficient (0.76 to 0.99 vs 0.60 to 0.97). The reliability of SurgimapSpine measures was significantly higher in all parameters except for the coronal Cobb angle where the difference was not significant (P > 0.05). Although the differences between the two methods are very small, the results of this study indicate that the SurgimapSpine measurement is an equivalent measuring tool to the traditional manual in coronal Cobb angle, but is advantageous in spino

Reliability and reproducibility analysis of the Cobb angle and assessing sagittal plane by computer-assisted and manual measurement tools

PubMed Central

2014-01-01

Background Although many studies on reliability and reproducibility of measurement have been performed on coronal Cobb angle, few results about reliability and reproducibility are reported on sagittal alignment measurement including the pelvis. We usually use SurgimapSpine software to measure the Cobb angle in our studies; however, there are no reports till date on its reliability and reproducible measurements. Methods Sixty-eight standard standing posteroanterior whole-spine radiographs were reviewed. Three examiners carried out the measurements independently under the settings of manual measurement on X-ray radiographies and SurgimapSpine software on the computer. Parameters measured included pelvic incidence, sacral slope, pelvic tilt, Lumbar lordosis (LL), thoracic kyphosis, and coronal Cobb angle. SPSS 16.0 software was used for statistical analyses. The means, standard deviations, intraclass and interclass correlation coefficient (ICC), and 95% confidence intervals (CI) were calculated. Results There was no notable difference between the two tools (P = 0.21) for the coronal Cobb angle. In the sagittal plane parameters, the ICC of intraobserver reliability for the manual measures varied from 0.65 (T2–T5 angle) to 0.95 (LL angle). Further, for SurgimapSpine tool, the ICC ranged from 0.75 to 0.98. No significant difference in intraobserver reliability was found between the two measurements (P > 0.05). As for the interobserver reliability, measurements with SurgimapSpine tool had better ICC (0.71 to 0.98 vs 0.59 to 0.96) and Pearson’s coefficient (0.76 to 0.99 vs 0.60 to 0.97). The reliability of SurgimapSpine measures was significantly higher in all parameters except for the coronal Cobb angle where the difference was not significant (P > 0.05). Conclusion Although the differences between the two methods are very small, the results of this study indicate that the SurgimapSpine measurement is an equivalent measuring tool to the traditional manual

A model of cerebrocerebello-spinomuscular interaction in the sagittal control of human walking.

PubMed

Jo, Sungho; Massaquoi, Steve G

2007-03-01

A computationally developed model of human upright balance control (Jo and Massaquoi on Biol cybern 91:188-202, 2004) has been enhanced to describe biped walking in the sagittal plane. The model incorporates (a) non-linear muscle mechanics having activation level -dependent impedance, (b) scheduled cerebrocerebellar interaction for control of center of mass position and trunk pitch angle, (c) rectangular pulse-like feedforward commands from a brainstem/ spinal pattern generator, and (d) segmental reflex modulation of muscular synergies to refine inter-joint coordination. The model can stand when muscles around the ankle are coactivated. When trigger signals activate, the model transitions from standing still to walking at 1.5 m/s. Simulated natural walking displays none of seven pathological gait features. The model can simulate different walking speeds by tuning the amplitude and frequency in spinal pattern generator. The walking is stable against forward and backward pushes of up to 70 and 75 N, respectively, and with sudden changes in trunk mass of up to 18%. The sensitivity of the model to changes in neural parameters and the predicted behavioral results of simulated neural system lesions are examined. The deficit gait simulations may be useful to support the functional and anatomical correspondences of the model. The model demonstrates that basic human-like walking can be achieved by a hierarchical structure of stabilized-long loop feedback and synergy-mediated feedforward controls. In particular, internal models of body dynamics are not required.

Ipsilateral hip abductor weakness after inversion ankle sprain.

PubMed

Friel, Karen; McLean, Nancy; Myers, Christine; Caceres, Maria

2006-01-01

Hip stability and strength are important for proper gait mechanics and foot position during heel strike. To determine the relationships between hip muscle strength and chronic ankle sprains and hip muscle strength and ankle range of motion. Ex post facto design with the uninvolved limb serving as the control. Laboratory. A total of 23 subjects with unilateral chronic ankle sprain were recruited. Subjects had at least 2 ipsilateral ankle sprains and were bearing full weight, with the most recent injury occurring at least 3 months earlier. They were not undergoing formal or informal rehabilitation at the time of the study. We obtained goniometric measurements for all planes of motion at the ankle. Handheld dynamometry was used to assess the strength of the hip abductor and hip extensor muscles in both limbs. Hip abductor muscle strength and plantar flexion were significantly less on the involved side than the uninvolved side (P < .001 in each case). Strength of the involved hip abductor and hip extensor muscles was significantly correlated (r = 0.539, P < .01). No significant difference was noted in hip extensor muscle strength between sides (P = .19). Our subjects with unilateral chronic ankle sprains had weaker hip abduction strength and less plantar-flexion range of motion on the involved sides. Clinicians should consider exercises to increase hip abduction strength when developing rehabilitation programs for patients with ankle sprains.

Alteration of the end-plane angle in press-fit cylindrical stem radial head prosthesis: an in vitro study.

PubMed

Luenam, Suriya; Chalongviriyalert, Piti; Kosiyatrakul, Arkaphat; Thanawattano, Chusak

2012-01-01

Many studies comparing the morphology of native radial head with the prosthesis have been published. However, there is limited information regarding the postoperative alignment of the articular surface following the radial head replacement. The purpose of this study is to evaluate the alteration of the end-plane angle in the modular radial head prosthesis with a press-fit cementless cylindrical stem. The study used 36 cadaveric radii. The press-fit size prosthesis with cylindrical stem was inserted into each specimen. The end-plane angles of the radial head before and after prosthetic replacement, were measured in coronal and sagittal planes with a digital inclinometer. The data were analyzed by paired t-test. From paired t-test, there were statistically symmetrical end-plane angles before and after radial head replacement in both coronal and sagittal planes (p-value < 0.01). The mean of radial head end-plane angle alteration in the coronal plane was 3.62° (SD, 2.76°) (range, 0.3°-8.9°). In the sagittal plane, the mean of alteration was 5.85° (SD, 3.56°) degrees (range, 0.3° - 14.2°). The modular radial head prosthesis with cylindrical stem is in vitro able to restore the native end-plane angles of radial heads statistically when used in a press-fit fashion.

Angle and Base of Gait Long Leg Axial and Intraoperative Simulated Weightbearing Long Leg Axial Imaging to Capture True Frontal Plane Tibia to Calcaneus Alignment in Valgus and Varus Deformities of the Rearfoot and Ankle.

PubMed

Boffeli, Troy J; Waverly, Brett J

2016-01-01

The long leg axial view is primarily used to evaluate the frontal plane alignment of the calcaneus in relation to the long axis of the tibia when standing. This view allows both angular measurement and assessment for the apex of varus and valgus deformity of the rearfoot and ankle with clinical utility in the preoperative, intraoperative, and postoperative settings. The frontal plane alignment of the calcaneus to the long axis of the tibia is rarely fixed in the varus or valgus position because of the inherent flexibility of the foot and ankle, which makes patient positioning critical to obtain accurate and reproducible images. Inconsistent patient positioning and imaging techniques are commonly encountered with the long leg axial view for a variety of reasons, including the lack of a standardized or validated protocol. This angle and base of gait imaging protocol involves positioning the patient to align the tibia with the long axis of the foot, which is represented by the second metatarsal. Non-weightbearing long leg axial imaging is commonly performed intraoperatively, which requires a modified patient positioning technique to capture simulated weightbearing long leg axial images. A case series is presented to demonstrate our angle and base of gait long leg axial and intraoperative simulated weightbearing long leg axial imaging protocols that can be applied throughout all phases of patient care for various foot and ankle conditions. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Use of Pool Noodles for The Shoulder and Ankle

PubMed Central

2007-01-01

The purpose of this manuscript is to provide two clinical suggestions that are inexpensive, easy to fabricate, and very user-friendly activities that can be used for most patients and athletes. The first clinical suggestion is a method of restoring stability of the scapular muscles around the shoulder complex. Following a period of disuse, whether from a surgery or an injury, weakness may be present in the shoulder. This suggestion is an easy and inexpensive tool which can be used in restoring stability of the scapula in all planes of movement as well as combinations of these planes. The method can also be used as a progression from gravity assisted to gravity resisted active range of motion. The purpose of the second clinical suggestion is to provide an inexpensive and easy to use method of improving proprioception in the ankle. Ankle sprains are among the most common injuries seen in sports. Proprioceptive activities are used not only in the rehabilitation process following an injury but as a training tool to help prevent ankle injuries. This method can be used in the clinic, in a training facility, or as part of a home exercise program. PMID:21522214

Use of pool noodles for the shoulder and ankle.

PubMed

Nelson, Russell

2007-08-01

The purpose of this manuscript is to provide two clinical suggestions that are inexpensive, easy to fabricate, and very user-friendly activities that can be used for most patients and athletes. The first clinical suggestion is a method of restoring stability of the scapular muscles around the shoulder complex. Following a period of disuse, whether from a surgery or an injury, weakness may be present in the shoulder. This suggestion is an easy and inexpensive tool which can be used in restoring stability of the scapula in all planes of movement as well as combinations of these planes. The method can also be used as a progression from gravity assisted to gravity resisted active range of motion. The purpose of the second clinical suggestion is to provide an inexpensive and easy to use method of improving proprioception in the ankle. Ankle sprains are among the most common injuries seen in sports. Proprioceptive activities are used not only in the rehabilitation process following an injury but as a training tool to help prevent ankle injuries. This method can be used in the clinic, in a training facility, or as part of a home exercise program.

Influence of implant rod curvature on sagittal correction of scoliosis deformity.

PubMed

Salmingo, Remel Alingalan; Tadano, Shigeru; Abe, Yuichiro; Ito, Manabu

2014-08-01

Deformation of in vivo-implanted rods could alter the scoliosis sagittal correction. To our knowledge, no previous authors have investigated the influence of implanted-rod deformation on the sagittal deformity correction during scoliosis surgery. To analyze the changes of the implant rod's angle of curvature during surgery and establish its influence on sagittal correction of scoliosis deformity. A retrospective analysis of the preoperative and postoperative implant rod geometry and angle of curvature was conducted. Twenty adolescent idiopathic scoliosis patients underwent surgery. Average age at the time of operation was 14 years. The preoperative and postoperative implant rod angle of curvature expressed in degrees was obtained for each patient. Two implant rods were attached to the concave and convex side of the spinal deformity. The preoperative implant rod geometry was measured before surgical implantation. The postoperative implant rod geometry after surgery was measured by computed tomography. The implant rod angle of curvature at the sagittal plane was obtained from the implant rod geometry. The angle of curvature between the implant rod extreme ends was measured before implantation and after surgery. The sagittal curvature between the corresponding spinal levels of healthy adolescents obtained by previous studies was compared with the implant rod angle of curvature to evaluate the sagittal curve correction. The difference between the postoperative implant rod angle of curvature and normal spine sagittal curvature of the corresponding instrumented level was used to evaluate over or under correction of the sagittal deformity. The implant rods at the concave side of deformity of all patients were significantly deformed after surgery. The average degree of rod deformation Δθ at the concave and convex sides was 15.8° and 1.6°, respectively. The average preoperative and postoperative implant rod angle of curvature at the concave side was 33.6° and 17.8�

Identifying changes in gait waveforms following a strengthening intervention for women with knee osteoarthritis using principal components analysis.

PubMed

Brenneman, Elora C; Maly, Monica R

2018-01-01

Lower limb strengthening exercise is pivotal for the management of symptoms related to knee osteoarthritis (OA). Though improvement in clinical symptoms is well documented, concurrent changes in gait biomechanics are ill-defined. This may occur because discrete analyses miss changes following an intervention, analyses limited to the knee undermine potential mechanical trade-offs at other joints, or strengthening interventions not been designed based on biomechanical principles. The purpose of this study was to characterize differences in entire gait waveforms for sagittal plane ankle, knee, and hip angles and external moments; the knee adduction moment; and frontal plane hip angle and moment following 12-weeks of a previously designed novel lower limb strengthening program. Forty women with knee OA completed two laboratory visits: one at baseline and one immediately following intervention (follow-up). Self-report measures, strength, and gait analyses were completed at each visit. Principal components analyses were completed for sagittal angles and external moments at the ankle, knee, and hip joints, as well as frontal plane angle and moment for the hip. Participants improved self-report and strength (p≤0.004). Two significant, yet subtle differences in principal components were identified between baseline and follow-up waveforms (p<0.05) pertaining to the knee and hip sagittal external moments. The subtle changes in concert with the lack of differences in other joints and planes suggest the lower limb strengthening program does not translate to changes in the gait waveform. It is likely this program is improving symptoms without worsening mechanics. Copyright © 2017 Elsevier B.V. All rights reserved.

Does the subtalar joint compensate for ankle malalignment in end-stage ankle arthritis?

PubMed

Wang, Bibo; Saltzman, Charles L; Chalayon, Ornusa; Barg, Alexej

2015-01-01

measured by two observers to determine the interobserver reliability. One of the observers evaluated all images twice to determine the intraobserver reliability. There were differences in medial distal tibial surface angle (86.6°±7.3° [95% CI, 66.3°-123.7°) versus 89.1°±2.9° [95% CI, 83.0°-96.3°], p<0.001), tibiotalar surface angle (84.9°±14.4° [95% CI, 45.3°-122.7°] versus 89.1°±2.9° [95% CI, 83.0°-96.3°], p<0.001), talar tilting angle (-1.7°±12.5° [95% CI, -41.3°-30.3°) versus 0.0°±0.0° [95% CI, 0.0°-0.0°], p=0.003), and tibiocalcaneal axis angle (-7.2°±13.1° [95% CI, -57°-33°) versus -2.7°±5.2° [95% CI, -13.3°-9.0°], p<0.001) between patients with ankle arthritis and the control group. Using the classification system based on the tibiocalcaneal angle, there were 62 (53%) and 22 (39%) compensated ankles in the varus and valgus groups, respectively. Using the classification system based on the moment arm of the calcaneus, there were 68 (58%) and 20 (35%) compensated ankles in the varus and valgus groups, respectively. For all conditions or methods of measurement, patients with no or mild degenerative change of the subtalar joint have a greater likelihood of compensating coronal plane deformity of the ankle with arthritis (p<0.001-p=0.032). The interobserver and intraobserver reliability for all radiographic measurements was good to excellent (the correlation coefficients range from 0.820 to 0.943). Substantial ankle malalignment, mostly varus deformity, is common in ankles with end-stage osteoarthritis. The subtalar joint often compensates for the malaligned ankle in static weightbearing. Level III, diagnostic study.

Investigation of sagittal image acquisition for 4D-MRI with body area as respiratory surrogate.

PubMed

Liu, Yilin; Yin, Fang-Fang; Chang, Zheng; Czito, Brian G; Palta, Manisha; Bashir, Mustafa R; Qin, Yujiao; Cai, Jing

2014-10-01

The authors have recently developed a novel 4D-MRI technique for imaging organ respiratory motion employing cine acquisition in the axial plane and using body area (BA) as a respiratory surrogate. A potential disadvantage associated with axial image acquisition is the space-dependent phase shift in the superior-inferior (SI) direction, i.e., different axial slice positions reach the respiratory peak at different respiratory phases. Since respiratory motion occurs mostly in the SI and anterior-posterior (AP) directions, sagittal image acquisition, which embeds motion information in these two directions, is expected to be more robust and less affected by phase-shift than axial image acquisition. This study aims to develop and evaluate a 4D-MRI technique using sagittal image acquisition. The authors evaluated axial BA and sagittal BA using both 4D-CT images (11 cancer patients) and cine MR images (6 healthy volunteers and 1 cancer patient) by comparing their corresponding space-dependent phase-shift in the SI direction (δSPS (SI)) and in the lateral direction (δSPS (LAT)), respectively. To evaluate sagittal BA 4D-MRI method, a motion phantom study and a digital phantom study were performed. Additionally, six patients who had cancer(s) in the liver were prospectively enrolled in this study. For each patient, multislice sagittal MR images were acquired for 4D-MRI reconstruction. 4D retrospective sorting was performed based on respiratory phases. Single-slice cine MRI was also acquired in the axial, coronal, and sagittal planes across the tumor center from which tumor motion trajectories in the SI, AP, and medial-lateral (ML) directions were extracted and used as references from comparison. All MR images were acquired in a 1.5 T scanner using a steady-state precession sequence (frame rate ∼ 3 frames/s). 4D-CT scans showed that δSPS (SI) was significantly greater than δSPS (LAT) (p-value: 0.012); the median phase-shift was 16.9% and 7.7%, respectively. Body surface

Neuromuscular strategies for lumbopelvic control during frontal and sagittal plane movement challenges differ between people with and without low back pain.

PubMed

Nelson-Wong, E; Poupore, K; Ingvalson, S; Dehmer, K; Piatte, A; Alexander, S; Gallant, P; McClenahan, B; Davis, A M

2013-12-01

Observation-based assessments of movement are a standard component in clinical assessment of patients with non-specific low back pain. While aberrant motion patterns can be detected visually, clinicians are unable to assess underlying neuromuscular strategies during these tests. The purpose of this study was to compare coordination of the trunk and hip muscles during 2 commonly used assessments for lumbopelvic control in people with low back pain (LBP) and matched control subjects. Electromyography was recorded from hip and trunk muscles of 34 participants (17 with LBP) during performance of the Active Hip Abduction (AHAbd) and Active Straight Leg Raise (ASLR) tests. Relative muscle timing was calculated using cross-correlation. Participants with LBP demonstrated a variable strategy, while control subjects used a consistent proximal to distal activation strategy during both frontal and sagittal plane movements. Findings from this study provide insight into underlying neuromuscular control during commonly used assessment tests for patients with LBP that may help to guide targeted intervention approaches. Copyright © 2013 Elsevier Ltd. All rights reserved.

Influence of trunk posture on lower extremity energetics during running.

PubMed

Teng, Hsiang-Ling; Powers, Christopher M

2015-03-01

This study aimed to examine the influence of sagittal plane trunk posture on lower extremity energetics during running. Forty asymptomatic recreational runners (20 males and 20 females) ran overground at a speed of 3.4 m·s(-1). Sagittal plane trunk kinematics and lower extremity kinematics and energetics during the stance phase of running were computed. Subjects were dichotomized into high flexion (HF) and low flexion (LF) groups on the basis of the mean trunk flexion angle. The mean (±SD) trunk flexion angles of the HF and LF groups were 10.8° ± 2.2° and 3.6° ± 2.8°, respectively. When compared with the LF group, the HF group demonstrated significantly higher hip extensor energy generation (0.12 ± 0.06 vs 0.05 ± 0.04 J·kg(-1), P < 0.001) and lower knee extensor energy absorption (0.60 ± 0.14 vs 0.74 ± 0.09 J·kg(-1), P = 0.001) and generation (0.30 ± 0.05 vs 0.34 ± 0.06 J·kg(-1), P = 0.02). There was no significant group difference for the ankle plantarflexor energy absorption or generation (P > 0.05). Sagittal plane trunk flexion has a significant influence on hip and knee energetics during running. Increasing forward trunk lean during running may be used as a strategy to reduce knee loading without increasing the biomechanical demand at the ankle plantarflexors.

Three-dimensional shear wave elastography for differentiation of breast lesions: An initial study with quantitative analysis using three orthogonal planes.

PubMed

Wang, Qiao

2018-05-25

To prospectively evaluate the diagnostic performance of three-dimensional (3D) shear wave elastography (SWE) for breast lesions with quantitative stiffness information from transverse, sagittal and coronal planes. Conventional ultrasound (US), two-dimensional (2D)-SWE and 3D-SWE were performed for 122 consecutive patients with 122 breast lesions before biopsy or surgical excision. Maximum elasticity values of Young's modulus (Emax) were recorded on 2D-SWE and three planes of 3D-SWE. Area under the receiver operating characteristic curve (AUC), sensitivity and specificity of US, 2D-SWE and 3D-SWE were evaluated. Two combined sets (i.e., BI-RADS and 2D-SWE; BI-RADS and 3D-SWE) were compared in AUC. Observer consistency was also evaluated. On 3D-SWE, the AUC and sensitivity of sagittal plane were significantly higher than those of transverse and coronal planes (both P < 0.05). Compared with BI-RADS alone, both combined sets had significantly (P < 0.05) higher AUCs and specificities, whereas, the two combined sets showed no significant difference in AUC (P > 0.05). However, the combined set of BI-RADS and sagittal plane of 3D-SWE had significantly higher sensitivity than the combined set of BI-RADS and 2D-SWE. The sagittal plane shows the best diagnostic performance among 3D-SWE. The combination of BI-RADS and 3D-SWE is a useful tool for predicting breast malignant lesions in comparison with BI-RADS alone.

The hip strength:ankle proprioceptive threshold ratio predicts falls and injury in diabetic neuropathy

PubMed Central

Richardson, James K.; DeMott, Trina; Allet, Lara; Kim; Ashton-Miller, James A.

2014-01-01

Introduction We determined lower limb neuromuscular capacities associated with falls and fall-related injuries in older people with declining peripheral nerve function. Methods Thirty-two subjects (67.4 ± 13.4 years; 19 with type 2 diabetes), representing a spectrum of peripheral neurologic function, were evaluated with frontal plane proprioceptive thresholds at the ankle, frontal plane motor function at the ankle and hip, and prospective follow-up for 1 year. Results Falls and fall-related injuries were reported by 20 (62.5%) and 14 (43.8%) subjects, respectively. The ratio of hip adductor rate of torque development to ankle proprioceptive threshold (HipSTR/AnkPRO) predicted falls (pseudo-R2 = .726) and injury (pseudo-R2 = .382). No other variable maintained significance in the presence of HipSTR/AnkPRO. Discussion Fall and injury risk in the population studied is related inversely to HipSTR/AnkPRO. Increasing rapidly available hip strength in patients with neuropathic ankle sensory impairment may decrease risk of falls and related injuries. PMID:24282041

Ipsilateral Hip Abductor Weakness After Inversion Ankle Sprain

PubMed Central

Friel, Karen; McLean, Nancy; Myers, Christine; Caceres, Maria

2006-01-01

Context: Hip stability and strength are important for proper gait mechanics and foot position during heel strike. Objective: To determine the relationships between hip muscle strength and chronic ankle sprains and hip muscle strength and ankle range of motion. Design: Ex post facto design with the uninvolved limb serving as the control. Setting: Laboratory. Patients or Other Participants: A total of 23 subjects with unilateral chronic ankle sprain were recruited. Subjects had at least 2 ipsilateral ankle sprains and were bearing full weight, with the most recent injury occurring at least 3 months earlier. They were not undergoing formal or informal rehabilitation at the time of the study. Main Outcome Measure(s): We obtained goniometric measurements for all planes of motion at the ankle. Handheld dynamometry was used to assess the strength of the hip abductor and hip extensor muscles in both limbs. Results: Hip abductor muscle strength and plantar flexion were significantly less on the involved side than the uninvolved side (P < .001 in each case). Strength of the involved hip abductor and hip extensor muscles was significantly correlated (r = 0.539, P < .01). No significant difference was noted in hip extensor muscle strength between sides (P = .19). Conclusions: Our subjects with unilateral chronic ankle sprains had weaker hip abduction strength and less plantar-flexion range of motion on the involved sides. Clinicians should consider exercises to increase hip abduction strength when developing rehabilitation programs for patients with ankle sprains. PMID:16619098

Relationship between viscosity of the ankle joint complex and functional ankle instability for inversion ankle sprain patients.

PubMed

Lin, Che-Yu; Kang, Jiunn-Horng; Wang, Chung-Li; Shau, Yio-Wha

2015-03-01

Measurement of viscosity of the ankle joint complex is a novel method to assess mechanical ankle instability. In order to further investigate the clinical significance of the method, this study intended to investigate the relationship between ankle viscosity and severity of functional ankle instability. Cross-sectional study. 15 participants with unilateral inversion ankle sprain and 15 controls were recruited. Their ankles were further classified into stable and unstable ankles. Ankle viscosity was measured by an instrumental anterior drawer test. Severity of functional ankle instability was measured by the Cumberland Ankle Instability Tool. Unstable ankles were compared with stable ankles. Injured ankles were compared with uninjured ankles of both groups. The spearman's rank correlation coefficient was applied to determine the relationship between ankle viscosity and severity of functional ankle instability in unstable ankles. There was a moderate relationship between ankle viscosity and severity of functional ankle instability (r=-0.64, p<0.0001). Unstable ankles exhibited significantly lower viscosity (p<0.005) and more severe functional ankle instability (p<0.0001) than stable ankles. Injured ankles exhibited significantly lower viscosity and more severe functional ankle instability than uninjured ankles (p<0.0001). There was a moderate relationship between ankle viscosity and severity of functional ankle instability. This finding suggested that, severity of functional ankle instability may be partially attributed to mechanical insufficiencies such as the degenerative changes in ankle viscosity following the inversion ankle sprain. In clinical application, measurement of ankle viscosity could be a useful tool to evaluate severity of chronic ankle instability. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Comparison of Joint Loading in Badminton Lunging between Professional and Amateur Badminton Players

PubMed Central

Fu, Lin

2017-01-01

The knee and ankle are the two most injured joints associated with the sport of badminton. This study evaluates biomechanical factors between professional and amateur badminton players using an injury mechanism model. The aim of this study was to investigate the kinematic motion and kinetic loading differences of the right knee and ankle while performing a maximal right lunge. Amateur players exhibited greater ankle range of motion (p < 0.05, r = 0.89) and inversion joint moment (p < 0.05, r = 0.54) in the frontal plane as well as greater internal joint rotation moment (p < 0.05, r = 0.28) in the horizontal plane. In contrast, professional badminton players presented a greater knee joint moment in the sagittal (p < 0.05, r = 0.59) and frontal (p < 0.05, r = 0.37) planes, which may be associated with increased knee ligamentous injury risk. To avoid injury, the players need to forcefully extend the knee with internal rotation, strengthen the muscles around the ankle ligament, and maximise joint coordination during training. The injuries recorded and the forces responsible for the injuries seem to have developed during training activity. Training programmes and injury prevention strategies for badminton players should account for these findings to reduce potential injury to the ankle and knee. PMID:28694684

Correlation and sex differences between ankle and knee cartilage morphology determined by quantitative magnetic resonance imaging

PubMed Central

Eckstein, F; Siedek, V; Glaser, C; Al-Ali, D; Englmeier, K; Reiser, M; Graichen, H

2004-01-01

Objective: To study the correlation between ankle and knee cartilage morphology to test the hypothesis that knee joint cartilage loss in gonarthritis can be estimated retrospectively using quantitative MRI analysis of the knee and ankle and established regression equations; and to test the hypothesis that sex differences in joint surface area are larger in the knee than the ankle, which may explain the greater incidence of knee osteoarthritis in elderly women than in elderly men. Methods: Sagittal MR images (3D FLASH WE) of the knee and hind foot were acquired in 29 healthy subjects (14 women, 15 men; mean (SD) age, 25 (3) years), with no signs joint disease. Cartilage volume, thickness, and joint surface area were determined in the knee, ankle, and subtalar joint. Results: Knee cartilage volumes and joint surface areas showed only moderate correlations with those of the ankle and subtalar joint (r = 0.33 to 0.81). The correlations of cartilage thickness between the two joints were weaker still (r = –0.05 to 0.53). Sex differences in cartilage morphology at the knee and the ankle were similar, with surface areas being –17.5% to –23.5% lower in women than in men. Conclusions: Only moderate correlations in cartilage morphology of healthy subjects were found between knee and ankle. It is therefore impractical to estimate knee joint cartilage loss a posteriori in cross sectional studies by measuring the hind foot and then applying a scaling factor. Sex differences in cartilage morphology do not explain differences in osteoarthritis incidence between men and women in the knee and ankle. PMID:15479900

Reliability of 3-Dimensional Measures of Single-Leg Drop Landing Across 3 Institutions: Implications for Multicenter Research for Secondary ACL-Injury Prevention.

PubMed

Myer, Gregory D; Bates, Nathaniel A; DiCesare, Christopher A; Barber Foss, Kim D; Thomas, Staci M; Wordeman, Samuel C; Sugimoto, Dai; Roewer, Benjamin D; Medina McKeon, Jennifer M; Di Stasi, Stephanie L; Noehren, Brian W; McNally, Michael; Ford, Kevin R; Kiefer, Adam W; Hewett, Timothy E

2015-05-01

Due to the limitations of single-center studies in achieving appropriate sampling with relatively rare disorders, multicenter collaborations have been proposed to achieve desired sampling levels. However, documented reliability of biomechanical data is necessary for multicenter injury-prevention studies and is currently unavailable. To measure the reliability of 3-dimensional (3D) biomechanical waveforms from kinetic and kinematic variables during a single-leg landing (SLL) performed at 3 separate testing facilities. Multicenter reliability study. 3 laboratories. 25 female junior varsity and varsity high school volleyball players who visited each facility over a 1-mo period. Subjects were instrumented with 43 reflective markers to record 3D motion as they performed SLLs. During the SLL the athlete balanced on 1 leg, dropped down off of a 31-cm-high box, and landed on the same leg. Kinematic and kinetic data from both legs were processed from 2 trials across the 3 laboratories. Coefficients of multiple correlations (CMC) were used to statistically compare each joint angle and moment waveform for the first 500 ms of landing. Average CMC for lower-extremity sagittal-plane motion was excellent between laboratories (hip .98, knee .95, ankle .99). Average CMC for lower-extremity frontal-plane motion was also excellent between laboratories (hip .98, knee .80, ankle .93). Kinetic waveforms were repeatable in each plane of rotation (3-center mean CMC ≥.71), while knee sagittal-plane moments were the most consistent measure across sites (3-center mean CMC ≥.94). CMC waveform comparisons were similar relative to the joint measured to previously published reports of between-sessions reliability of sagittal- and frontal-plane biomechanics performed at a single institution. Continued research is needed to further standardize technology and methods to help ensure that highly reliable results can be achieved with multicenter biomechanical screening models.

Ankle moment generation and maximum-effort curved sprinting performance.

PubMed

Luo, Geng; Stefanyshyn, Darren

2012-11-15

Turning at high speed along acute curves is crucial for athletic performance. One determinant of curved sprinting speed is the ground reaction force that can be created by the supporting limb; the moment generated at the ankle joint may influence such force generation. Body lean associated with curved sprints positions the ankle joints in extreme in-/eversion, and may hinder the ankle moment generation. To examine the influence of ankle moment generation on curved sprinting performance, 17 male subjects performed maximum-effort curved sprints in footwear with and without a wedge. The wedged footwear was constructed with the intention to align the ankle joints closer to their neutral frontal-plane configuration during counter-clockwise curved sprints so greater joint moments might be generated. We found, with the wedged footwear, the average eversion angle of the inside leg ankle was reduced, and the plantarflexion moment generation increased significantly. Meanwhile, the knee extension moment remained unchanged. With the wedged footwear, stance-average centripetal ground reaction force increased significantly while no difference in the vertical ground reaction force was detected. The subjects created a greater centripetal ground reaction impulse in the wedged footwear despite a shortened stance phase when compared to the control. Stance-average curved sprinting speed improved by 4.3% with the wedged footwear. The changes in ankle moment and curved sprinting speed observed in the current study supports the notion that the moment generation at the ankle joint may be a performance constraint for curved sprinting. Copyright © 2012 Elsevier Ltd. All rights reserved.

Two-plane symmetry in the structural organization of man.

PubMed

Ermolenko, A E

2005-01-01

Manifestations of symmetry in the human structural organization in ontogenesis and phylogenetic development are analysed. A concept of macrobiocrystalloid with inherent complex symmetry is proposed for the description of the human organism in its integrity. The symmetry can be characterized as two-plane radial (quadrilateral), where the planar symmetry is predominant while the layout of organs of radial symmetry is subordinated to it. Out of the two planes of symmetry (sagittal and horizontal), the sagittal plane is predominant: (a) the location of the organs is governed by two principles: in compliance with the symmetry planes and in compliance with the radial symmetry around cavities; (b) the location of the radial symmetry organs is also governed by the principle of two-plane symmetry; (c) out of the four antimeres of two-plane symmetry, two are paired while the other two have merged into one organ; (d) some organs which are antimeres relative to the horizontal plane are located at the cranial end of the organism (sensory organs, cerebrum-cerebellum, heart-spleen and others). The two-plane symmetry is formed by two mechanisms--(a) the impact of morphogenetic fields of the whole crystalloid organism during embriogenesis and (b) genetic mechanisms of the development of chromosomes having two-plane symmetry. When comparing mineral and biological entities we should consider not the whole immobile crystal but only the active superficial part of a growing or dissolving crystal, the interface between the crystal surface and the crystal-forming environment which directly controls crystal growth and adapts itself to it, as well as crystal feed stock expressed in the structure of concentration flows. The symmetry of the chromosome, of the embrion at the early stages of cell cleavage as well as of some organs and systems in their phylogenetic development is described.

Are There Differences in Gait Mechanics in Patients With A Fixed Versus Mobile Bearing Total Ankle Arthroplasty? A Randomized Trial.

PubMed

Queen, Robin M; Franck, Christopher T; Schmitt, Daniel; Adams, Samuel B

2017-10-01

Total ankle arthroplasty (TAA) is an alternative to arthrodesis, but no randomized trial has examined whether a fixed bearing or mobile bearing implant provides improved gait mechanics. We wished to determine if fixed- or mobile-bearing TAA results in a larger improvement in pain scores and gait mechanics from before surgery to 1 year after surgery, and to quantify differences in outcomes using statistical analysis and report the standardized effect sizes for such comparisons. Patients with end-stage ankle arthritis who were scheduled for TAA between November 2011 and June 2013 (n = 40; 16 men, 24 women; average age, 63 years; age range, 35-81 years) were prospectively recruited for this study from a single foot and ankle orthopaedic clinic. During this period, 185 patients underwent TAA, with 144 being eligible to participate in this study. Patients were eligible to participate if they were able to meet all study inclusion criteria, which were: no previous diagnosis of rheumatoid arthritis, a contralateral TAA, bilateral ankle arthritis, previous revision TAA, an ankle fusion revision, or able to walk without the use of an assistive device, weight less than 250 pounds (114 kg), a sagittal or coronal plane deformity less than 15°, no presence of avascular necrosis of the distal tibia, no current neuropathy, age older than 35 years, no history of a talar neck fracture, or an avascular talus. Of the 144 eligible patients, 40 consented to participate in our randomized trial. These 40 patients were randomly assigned to either the fixed (n = 20) or mobile bearing implant group (n = 20). Walking speed, bilateral peak dorsiflexion angle, peak plantar flexion angle, sagittal plane ankle ROM, peak ankle inversion angle, peak plantar flexion moment, peak plantar flexion power during stance, peak weight acceptance, and propulsive vertical ground reaction force were analyzed during seven self-selected speed level walking trials for 33 participants using an eight

Associations between lower extremity muscle mass and multiplanar knee laxity and stiffness: a potential explanation for sex differences in frontal and transverse plane knee laxity.

PubMed

Shultz, Sandra J; Pye, Michele L; Montgomery, Melissa M; Schmitz, Randy J

2012-12-01

Compared with men, women have disproportionally greater frontal (varus-valgus) and transverse (internal-external) plane laxity and lower stiffness, despite having similar sagittal (anterior-posterior) plane laxity and stiffness. While the underlying cause is unclear, the amount of lower extremity lean mass (LELM) may be a contributing factor. Lower extremity lean mass would be a stronger predictor of frontal and transverse plane laxity and incremental stiffness than the sagittal plane. Associations between LELM and stiffness would be stronger at lower force increments. Descriptive laboratory study. Sixty-three women and 30 men with no history of ligament injury were measured for knee laxity and incremental stiffness in the sagittal (-90- to 130-N posterior-to-anterior directed loads), frontal (±10-N·m varus-valgus torques), and transverse (±5-N·m internal-external rotation torques) planes and underwent dual-energy X-ray absorptiometry scans to measure LELM. Linear regressions examined the extent to which LELM predicted each laxity and stiffness value, while also accounting for a person's sex. Females (vs males) had greater laxity and less stiffness in the frontal and transverse planes but not the sagittal plane. Lower extremity lean mass was a poor predictor of sagittal laxity and stiffness (R (2) range = .021-.081; P > .06) but was a stronger predictor of frontal (R (2) range = .215-.567; P < .01) and transverse (R (2) range = .224-.356; P < .01) plane laxity and stiffness. Associations were stronger for low (R (2) = .495-.504) versus high (R (2) = .215-.435) frontal plane stiffness but were similar for low (R (2) = .233-.293) versus high (R (2) = .224-.356) transverse plane stiffness. Once we accounted for a person's LELM, sex had little effect on laxity and stiffness (change in R (2) after removal = .01-.08; P = .027-.797). Less LELM was associated with greater laxity and less stiffness in frontal and transverse planes, which may contribute to the

Medial compressible forefoot sole elements reduce ankle inversion in lateral SSC jumps.

PubMed

Fleischmann, Jana; Mornieux, Guillaume; Gehring, Dominic; Gollhofer, Albert

2013-06-01

Sideward movements are associated with high incidences of lateral ankle sprains. Special shoe constructions might be able to reduce these injuries during lateral movements. The purpose of this study was to investigate whether medial compressible forefoot sole elements can reduce ankle inversion in a reactive lateral movement, and to evaluate those elements' influence on neuromuscular and mechanical adjustments in lower extremities. Foot placement and frontal plane ankle joint kinematics and kinetics were analyzed by 3-dimensional motion analysis. Electromyographic data of triceps surae, peroneus longus, and tibialis anterior were collected. This modified shoe reduced ankle inversion in comparison with a shoe with a standard sole construction. No differences in ankle inversion moments were found. With the modified shoe, foot placement occurred more internally rotated, and muscle activity of the lateral shank muscles was reduced. Hence, lateral ankle joint stability during reactive sideward movements can be improved by these compressible elements, and therefore lower lateral shank muscle activity is required. As those elements limit inversion, the strategy to control inversion angles via a high external foot rotation does not need to be used.

Sagittal plane analysis of selective posterior thoracic spinal fusion in adolescent idiopathic scoliosis: a comparison study of all pedicle screw and hybrid instrumentation.

PubMed

Liu, Tie; Hai, Yong

2014-07-01

To compare sagittal profiles of selective posterior thoracic instrumentation with segmental pedicle screws instrumentation and hybrid (hook and pedicle screw). Nowadays, thoracic screws are considered more effective than other constructs in spinal deformity correction and have become the treatment in adolescent idiopathic scoliosis surgery. However, recent research found that this enhanced correction ability may sacrifice sagittal balance. As lumbar lordosis is dependent upon thoracic kyphosis (TK), it has been important to maintain TK magnitude in selective thoracic fusions to keep balance. There is no sagittal measurement analysis between the hybrid and all-screw constructs type in cases of selective thoracic fusion. All adolescent idiopathic scoliosis (Lenke1) patients surgically treated in our department between 2003 and 2008 were reviewed. Radiographs of these patients, whose preoperative, immediately postoperative, and minimum 2-year follow-up after selective thoracic fusion (lower instrumented vertebrae not lower than L1, hybrid group the pedicle screw instrumentation not higher than T10) were evaluated, 21 patients underwent posterior hybrid instrumentation and 21 underwent pedicle screw instrumentation. No significant difference in sagittal profiles was observed between the 2 groups. At final follow-up, the proximal junctional measurement has a minor increase in both the groups. TK (T5-T12) also increased (+2.0 degrees of increase in hybrid group vs. +3.9 degrees of increase in the pedicle screw group). The effect of different instrumentation in changing TK at various time points between 2 groups was statistic different (P=0.004). Lumbar lordosis (L1-L5) was increased in both the groups. No significant changes in distal junctional measurement and thoracolumbar junction were noted. The C7 sagittal plumbline remained negative in both the groups at the final follow-up. There was no statistically significant difference comparing the sagittal alignment

Oblique Sagittal Images Prevent Underestimation of the Neuroforaminal Stenosis Grade Caused by Disc Herniation in Cervical Spine MRI.

PubMed

Kintzelé, Laurent; Rehnitz, Christoph; Kauczor, Hans-Ulrich; Weber, Marc-André

2018-06-06

 To identify whether standard sagittal MRI images result in underestimation of the neuroforaminal stenosis grade compared to oblique sagittal MRI images in patients with cervical spine disc herniation.  74 patients with a total of 104 cervical disc herniations compromising the corresponding nerve root were evaluated. Neuroforaminal stenosis grades were evaluated in standard and oblique sagittal images by one senior and one resident radiologist experienced in musculoskeletal imaging. Oblique images were angled 30° towards the standard sagittal plane. Neuroforaminal stenosis grades were classified from 0 (no stenosis) to 3 (high grade stenosis).  Average neuroforaminal stenosis grades of both readers were significantly lower in standard compared to oblique sagittal images (p < 0.001). For 47.1 % of the cases, one or both readers reported a stenosis grade, which was at least 1 grade lower in standard compared to oblique sagittal images. There was also a significant difference when looking at patients who had neurological symptoms (p = 0.002) or underwent cervical spine surgery subsequently (p = 0.004). Interreader reliability, as measured by kappa value, and accordance rates were better for oblique sagittal images (0.94 vs. 0.88 and 99 % vs. 93 %).  Standard sagittal images tend to underestimate neuroforaminal stenosis grades compared to oblique sagittal images and are less reliable in the evaluation of disc herniations within the cervical spine MRI. In order to assess the potential therapeutic consequence, oblique images should therefore be considered as a valuable adjunct to the standard MRI protocol for patients with a radiculopathy.   · Neuroforaminal stenosis grades are underestimated in standard compared to oblique sagittal images. · Interreader reliability is higher for oblique sagittal images. · Oblique sagittal images should be performed in patients with a cervical radiculopathy. · Kintzele L, Rehnitz C, Kauczor H et�

The biomechanical characteristics of wearing FitFlop™ sandals highlight significant alterations in gait pattern: a comparative study.

PubMed

James, Darren C; Farmer, Laura J; Sayers, Jason B; Cook, David P; Mileva, Katya N

2015-05-01

The net contribution of all muscles that act about a joint can be represented as an internal joint moment profile. This approach may be advantageous when studying footwear-induced perturbations during walking since the contribution of the smaller deeper muscles that cross the ankle joint cannot be evaluated with surface electromyography. Therefore, the present study aimed to advance the understanding of FitFlop™ footwear interaction by investigating lower extremity joint moment, and kinematic and centre of pressure profiles during gait. 28 healthy participants performed 5 walking trials in 3 conditions: a FitFlop™ sandal, a conventional sandal and an athletic trainer. Three-dimensional ankle joint, and sagittal plane knee and hip joint moments, as well as corresponding kinematics and centre of pressure trajectories were evaluated. FitFlop™ differed significantly to both the conventional sandal and athletic trainer in: average anterior position of centre of pressure trajectory (P<0.0001) and peak hip extensor moment (P=0.001) during early stance; average medial position of centre of pressure trajectory during late stance; peak ankle dorsiflexion and corresponding range of motion; peak plantarflexor moment and total negative work performed at the ankle (all P<0.0001). The present findings demonstrate that FitFlop™ footwear significantly alters the gait pattern of wearers. An anterior displacement of the centre of pressure trajectory during early stance is the primary response to the destabilising effect of the mid-sole technology, and this leads to reductions in sagittal plane ankle joint range of motion and corresponding kinetics. Future investigations should consider the clinical implications of these findings. Copyright © 2015 Elsevier Ltd. All rights reserved.

Design and Preliminary Evaluation of a Two DOFs Cable-Driven Ankle–Foot Prosthesis with Active Dorsiflexion–Plantarflexion and Inversion–Eversion

PubMed Central

Ficanha, Evandro Maicon; Ribeiro, Guilherme Aramizo; Dallali, Houman; Rastgaar, Mohammad

2016-01-01

This paper describes the design of an ankle–foot robotic prosthesis controllable in the sagittal and frontal planes. The prosthesis was designed to meet the mechanical characteristics of the human ankle including power, range of motion, and weight. To transfer the power from the motors and gearboxes to the ankle–foot mechanism, a Bowden cable system was used. The Bowden cable allows for optimal placement of the motors and gearboxes in order to improve gait biomechanics such as the metabolic energy cost and gait asymmetry during locomotion. Additionally, it allows flexibility in the customization of the device to amputees with different residual limb sizes. To control the prosthesis, impedance controllers in both sagittal and frontal planes were developed. The impedance controllers used torque feedback from strain gages installed on the foot. Preliminary evaluation was performed to verify the capability of the prosthesis to track the kinematics of the human ankle in two degrees of freedom (DOFs), the mechanical efficiency of the Bowden cable transmission, and the ability of the prosthesis to modulate the impedance of the ankle. Moreover, the system was characterized by describing the relationship between the stiffness of the impedance controllers to the actual stiffness of the ankle. Efficiency estimation showed 85.4% efficiency in the Bowden cable transmission. The prosthesis was capable of properly mimicking human ankle kinematics and changing its mechanical impedance in two DOFs in real time with a range of stiffness sufficient for normal human walking. In dorsiflexion–plantarflexion (DP), the stiffness ranged from 0 to 236 Nm/rad and in inversion–eversion (IE), the stiffness ranged from 1 to 33 Nm/rad. PMID:27200342

Effects of two proprioceptive training programs on ankle range of motion, pain, functional and balance performance in individuals with ankle sprain.

PubMed

Lazarou, Lazaros; Kofotolis, Nikolaos; Pafis, Georgios; Kellis, Eleftherios

2017-09-08

Following ankle sprain, residual symptoms are often apparent, and proprioceptive training is a treatment approach. Evidence, however, is limited and the optimal program has to be identified. To investigate the effects of two post-acute supervised proprioceptive training programs in individuals with ankle sprain. Participants were recruited from a physiotherapy center for ankle sprain rehabilitation. In a pre-post treatment, blinded-assessor design, 22 individuals were randomly allocated to a balance or a proprioceptive neuromuscular facilitation (PNF) group. Both groups received 10 rehabilitation sessions, within a six-week period. Dorsiflexion range of motion (ROM), pain, functional and balance performance were assessed at baseline, at the end of training and eight weeks after training. Follow-up data were provided for 20 individuals. Eight weeks after training, statistically significant (p< 0.017) improvements were found in dorsiflexion ROM and most functional performance measures for both balance and PNF groups. Eight weeks after training, significant (p< 0.017) improvements in the frontal plane balance test and pain were observed for the balance group. Balance and PNF programs are recommended in clinical practice for improving ankle ROM and functional performance in individuals with sprain. Balance programs are also recommended for pain relief.

Once-per-step control of ankle-foot prosthesis push-off work reduces effort associated with balance during walking.

PubMed

Kim, Myunghee; Collins, Steven H

2015-05-01

Individuals with below-knee amputation have more difficulty balancing during walking, yet few studies have explored balance enhancement through active prosthesis control. We previously used a dynamical model to show that prosthetic ankle push-off work affects both sagittal and frontal plane dynamics, and that appropriate step-by-step control of push-off work can improve stability. We hypothesized that this approach could be applied to a robotic prosthesis to partially fulfill the active balance requirements of human walking, thereby reducing balance-related activity and associated effort for the person using the device. We conducted experiments on human participants (N = 10) with simulated amputation. Prosthetic ankle push-off work was varied on each step in ways expected to either stabilize, destabilize or have no effect on balance. Average ankle push-off work, known to affect effort, was kept constant across conditions. Stabilizing controllers commanded more push-off work on steps when the mediolateral velocity of the center of mass was lower than usual at the moment of contralateral heel strike. Destabilizing controllers enforced the opposite relationship, while a neutral controller maintained constant push-off work regardless of body state. A random disturbance to landing foot angle and a cognitive distraction task were applied, further challenging participants' balance. We measured metabolic rate, foot placement kinematics, center of pressure kinematics, distraction task performance, and user preference in each condition. We expected the stabilizing controller to reduce active control of balance and balance-related effort for the user, improving user preference. The best stabilizing controller lowered metabolic rate by 5.5% (p = 0.003) and 8.5% (p = 0.02), and step width variability by 10.0% (p = 0.009) and 10.7% (p = 0.03) compared to conditions with no control and destabilizing control, respectively. Participants tended to prefer stabilizing controllers

The contribution of two ears to the perception of vertical angle in sagittal planes.

PubMed

Morimoto, M

2001-04-01

Because the input signals to the left and right ears are not identical, it is important to clarify the role of these signals in the perception of the vertical angle of a sound source at any position in the upper hemisphere. To obtain basic findings on upper hemisphere localization, this paper investigates the contribution of each pinna to the perception of vertical angle. Tests measured localization of the vertical angle in five planes parallel to the median plane. In the localization tests, the pinna cavities of one or both ears were occluded. Results showed that pinna cavities of both the near and far ears play a role in determining the perceived vertical angle of a sound source in any plane, including the median plane. As a sound source shifts laterally away from the median plane, the contribution of the near ear increases and, conversely, that of the far ear decreases. For saggital planes at azimuths greater than 60 degrees from midline, the far ear no longer contributes measurably to the determination of vertical angle.

Use and tolerability of a side pole static ankle foot orthosis in children with neurological disorders.

PubMed

Delvert, Céline; Rippert, Pascal; Margirier, Françoise; Vadot, Jean-Pierre; Bérard, Carole; Poirot, Isabelle; Vuillerot, Carole

2017-04-01

Transverse-plane foot deformities are a frequently encountered issue in children with neurological disorders. They are the source of many symptoms, such as pain and walking difficulties, making their prevention very important. We aim to describe the use and tolerability of a side pole static ankle foot orthosis used to prevent transverse-plane foot deformities in children with neurologic disorders. Monocentric, retrospective, observational study. Medical data were collected from 103 children with transverse-plane foot deformities in one or both feet caused by a neurological impairment. All children were braced between 2001 and 2010. Unilateral orthosis was prescribed for 32 children and bilateral orthosis for 71. Transverse-plane foot deformities were varus in 66% of the cases and an equinus was associated in 59.2% of the cases. Mean age for the first prescription was 8.6 years. For the 23 patients present at the 4-year visit, 84.8% still wore the orthosis daily, and 64.7% wore the orthosis more than 6 h per day. The rate of permanent discontinuation of wearing the orthosis was 14.7%. The side pole static ankle foot orthosis is well tolerated with very few side effects, which promotes regular wearing and observance. Clinical relevance Side pole static ankle foot orthoses are well tolerated and can be safely used for children with foot abnormalities in the frontal plane that have a neurological pathology origin.

MRI to delineate the gross tumor volume of nasopharyngeal cancers: which sequences and planes should be used?

PubMed

Popovtzer, Aron; Ibrahim, Mohannad; Tatro, Daniel; Feng, Felix Y; Ten Haken, Randall K; Eisbruch, Avraham

2014-09-01

Magnetic resonance imaging (MRI) has been found to be better than computed tomography for defining the extent of primary gross tumor volume (GTV) in advanced nasopharyngeal cancer. It is routinely applied for target delineation in planning radiotherapy. However, the specific MRI sequences/planes that should be used are unknown. Twelve patients with nasopharyngeal cancer underwent primary GTV evaluation with gadolinium-enhanced axial T1 weighted image (T1) and T2 weighted image (T2), coronal T1, and sagittal T1 sequences. Each sequence was registered with the planning computed tomography scans. Planning target volumes (PTVs) were derived by uniform expansions of the GTVs. The volumes encompassed by the various sequences/planes, and the volumes common to all sequences/planes, were compared quantitatively and anatomically to the volume delineated by the commonly used axial T1-based dataset. Addition of the axial T2 sequence increased the axial T1-based GTV by 12% on average (p = 0.004), and composite evaluations that included the coronal T1 and sagittal T1 planes increased the axial T1-based GTVs by 30% on average (p = 0.003). The axial T1-based PTVs were increased by 20% by the additional sequences (p = 0.04). Each sequence/plane added unique volume extensions. The GTVs common to all the T1 planes accounted for 38% of the total volumes of all the T1 planes. Anatomically, addition of the coronal and sagittal-based GTVs extended the axial T1-based GTV caudally and cranially, notably to the base of the skull. Adding MRI planes and sequences to the traditional axial T1 sequence yields significant quantitative and anatomically important extensions of the GTVs and PTVs. For accurate target delineation in nasopharyngeal cancer, we recommend that GTVs be outlined in all MRI sequences/planes and registered with the planning computed tomography scans.

Ankle joint distraction arthroplasty for severe ankle arthritis.

PubMed

Xu, Yang; Zhu, Yuan; Xu, Xiang-Yang

2017-02-28

Ankle distraction arthroplasty is one option for the treatment of severe ankle arthritis in young patients. The outcomes and factors predicting success in distraction arthroplasty are poorly understood. From January 2011 to May 2015, 16 patients who had undergone ankle distraction arthroplasty for ankle arthritis were operated, including six males and ten females. All patients were available for analysis. The main outcome measurements included joint space on weight bearing radiographs, AOFAS-AH scores (American Orthopaedic Foot & Ankle Society ankle-hindfoot score), VAS scores and SF-36 scores. All 16 patients were followed for a mean follow-up of 40.9 ± 14.7 months (range, 17-67 months). Fourteen of the 16 patients still had their native ankle joints. One patient had undergone ankle arthrodesis 1 year after the operation and one patient had converted to spontaneous ankle fusion at the 3 years follow-up postoperative. The VAS score improved from 5.9 ± 0.8 to 3.7 ± 2.2 (p = 0.0028). The mean AOFAS-AH score improved from 41.9 ± 7.2 preoperatively to 68.1 ± 20.0 postoperatively (p = 0.001). The mean SF-36 score improved from 43.1 ± 7.6 preoperatively to 62.7 ± 18.8 postoperatively (p = 0.002). A weight-bearing ankle space larger than 3 mm at 1 year following distraction is a positive predictive factor. In this study, the treatment of ankle motion distraction for end stage ankle arthritis showed benefit in 9/16 (56.25%) patients at 41 months. It is a promising method for young patients with severe ankle arthritis.

Determining the sagittal relationship between the maxilla and the mandible: a cephalometric analysis to clear up the confusion.

PubMed

Davis, Glen S; Cannon, James L; Messersmith, Marion L

2013-01-01

Establishing the sagittal jaw relationship is a key component to developing a diagnosis when treating an orthodontic patient. Several measurements, including the Wits Appraisal, ANB angle and nasion perpendicular have been and are currently used by practitioners to diagnose the sagittal jaw relationship. Unfortunately, all of these measurements have their limitations. The Cannon Analysis was created in an attempt to help overcome these limitations. One hundred untreated patients from the Vanderbilt University Medical Center database were selected, and their initial lateral cephalometric radiographs were digitally traced utilizing the Cannon Cephalometric Analysis. All of these patients had an orthognathic profile, a Class I occlusion and a good skeletal balance as judged by the authors. Normative values were established for the Cannon Analysis and then broken down by sex and age (8-11, 12-18, 19 and over). An example case was analyzed using the Cannon Analysis and several diagnostic scenarios were reviewed. The variance or difference between Porion to A Point (Po-A) and Porion to B Point (Po-B) was found to be 12.6 mm. This value remained relatively constant throughout life, with only slightly higher values for males versus females. The Cannon Analysis is an effective way to accurately establish the sagittal jaw relationship since it is not affected by the anterior / posterior position of nasion, the steepness of the mandibular plane angle, nor an improperly drawn occlusal plane.

Comparison of biomechanical gait parameters of young children with haemophilia and those of age-matched peers.

PubMed

Stephensen, D; Drechsler, W; Winter, M; Scott, O

2009-03-01

Quality of life for children with haemophilia has improved since the introduction of prophylaxis. The frequency of joint haemorrhages has reduced, but the consequences of reduced bleeding on the biomechanical parameters of walking are not well understood. This study explored the differences in sagittal plane biomechanics of walking between a control group (Group 1) of normal age-matched children and children with haemophilia (Group 2) with a target ankle joint. A motion capture system and two force platforms were used to collect sagittal plane kinematic, kinetic and temporal-spatial data during walking of 14 age-matched normal children and 14 children with haemophilia aged 7-13 years. Group differences in maximum and minimum flexion/extension angles and moments of the hip, knee and ankle joints, ground reaction forces and temporal-spatial gait cycle parameters were analysed using one-way anova. Significant changes (P < 0.05) in kinematic and kinetic parameters but not temporal-spatial parameters were found in children with haemophilia; greater flexion angles and external moments of force at the knee, greater ankle plantarflexion external moments and lower hip flexion external moments. These results suggest that early biomechanical changes are present in young haemophilic children with a history of a target ankle joint and imply that lower limb joint function is more impaired than current clinical evaluations indicate. Protocols and quantitative data on the biomechanical gait pattern of children with haemophilia reported in this study provide a baseline to evaluate lower limb joint function and clinical progression.

Analysis of sagittal spinopelvic parameters in achondroplasia.

PubMed

Hong, Jae-Young; Suh, Seung-Woo; Modi, Hitesh N; Park, Jong-Woong; Park, Jung-Ho

2011-08-15

Prospective radiological analysis of patients with achondroplasia. To analyze sagittal spinal alignment and pelvic orientation in achondroplasia patients. Knowledge of sagittal spinopelvic parameters is important for the treatment of achondroplasia, because they differ from those of the normal population and can induce pain. The study and control groups were composed of 32 achondroplasia patients and 24 healthy volunteers, respectively. All underwent lateral radiography of the whole spine including hip joints. The radiographic parameters examined were sacral slope (SS), pelvic tilt, pelvic incidence (PI), S1 overhang, thoracic kyphosis, T10-L2 kyphosis, lumbar lordosis (LL1, LL2), and sagittal balance. Statistical analysis was performed to identify significant differences between the two groups. In addition, correlations between parameters and symptoms were sought. Sagittal spinopelvic parameters, namely, pelvic tilt, pelvic incidence, S1 overhang, thoracic kyphosis, T10-L2 kyphosis, lumbar lordosis 1 and sagittal balance were found to be significantly different in the patient and control groups (P < 0.05). In addition, sagittal parameters were found to be related to each other in the patient group (P < 0.05), that is, PI was related to SS and pelvic tilt, and LL was related to thoracic kyphosis. Furthermore, in terms of relations between spinal and pelvic parameters, LL was related to SS and PI, and sagittal balance was related to SS and PI. Furthermore, LL and T10-L2 kyphosis were found to be related to pain (P < 0.05), whereas no other parameter was found to be related to VAS scores. Sagittal parameters and possible relationships between sagittal parameters and symptoms were found to be significantly different in achondroplasia patients and normal healthy controls. The present study shows that sagittal spinal and pelvic parameters can assist the treatment of spinal disorders in achondroplasia patients.

Modification of the sagittal split osteotomy of the mandibular ramus: mobilizing vertical osteotomy of the internal ramus segment.

PubMed

Ricard, Daniel; Ferri, Joël

2009-08-01

We describe a new surgical procedure to improve stability when counterclockwise rotation of the maxillomandibular complex and the occlusal plane is intended. This preliminary prospective study evaluated 10 patients (8 female patients and 2 male patients) who each underwent maxillomandibular surgical advancement with counterclockwise rotation of the occlusal plane. A mandibular counterclockwise rotation was done in all cases with bilateral ramus sagittal split osteotomy. After the split of the ramus had been completed, a vertical osteotomy was done distally to the second molar on the internal ramus segment. With the completion of this vertical osteotomy, the internal ramus segment became completely mobile. All osteotomies were stabilized with rigid internal fixation by use of plates with monocortical screws. Ten patients have been treated with the "mobilizing vertical osteotomy of the internal ramus segment." The mean reduction of the occlusal plane angle was 10.1 degrees , showing a substantial counterclockwise rotation of the maxillomandibular complex. All patients had significant improvement of their facial balance. After a 1-year follow-up period, all cases but 1 showed very good stability of their occlusion and occlusal plane angle. An 11.4% relapse of the forward movement of the mandible was noted. On the basis of this prospective study, we conclude that when performing a counterclockwise rotation of the maxillomandibular complex, the mobilizing vertical osteotomy of the internal ramus segment combined with the sagittal split osteotomy of the mandible potentially enhances the occlusal plane angle and occlusal stability after a 1-year period.

Sagittal crest formation in great apes and gibbons.

PubMed

Balolia, Katharine L; Soligo, Christophe; Wood, Bernard

2017-06-01

The frequency of sagittal crest expression and patterns of sagittal crest growth and development have been documented in hominoids, including some extinct hominin taxa, and the more frequent expression of the sagittal crest in males has been traditionally linked with the need for larger-bodied individuals to have enough attachment area for the temporalis muscle. In the present study, we investigate sagittal cresting in a dentally mature sample of four hominoid taxa (Pan troglodytes schweinfurthii, Gorilla gorilla gorilla, Pongo pygmaeus pygmaeus and Hylobates lar). We investigate whether sagittal crest size increases with age beyond dental maturity in males and females of G. g. gorilla and Po. pyg. pygmaeus, and whether these taxa show sex differences in the timing of sagittal crest development. We evaluate the hypothesis that the larger sagittal crest of males may not be solely due to the requirement for a larger surface area than the un-crested cranial vault can provide for the attachment of the temporalis muscle, and present data on sex differences in temporalis muscle attachment area and sagittal crest size relative to cranial size. Gorilla g. gorilla and Po. pyg. pygmaeus males show significant relationships between tooth wear rank and sagittal crest size, and they show sagittal crest size differences between age groups that are not found in females. The sagittal crest emerges in early adulthood in the majority of G. g. gorilla males, whereas the percentage of G. g. gorilla females possessing a sagittal crest increases more gradually. Pongo pyg. pygmaeus males experience a three-fold increase in the number of specimens exhibiting a sagittal crest in mid-adulthood, consistent with a secondary growth spurt. Gorilla g. gorilla and Po. pyg. pygmaeus show significant sex differences in the size of the temporalis muscle attachment area, relative to cranial size, with males of both taxa showing positive allometry not shown in females. Gorilla g

LIMITED HIP AND KNEE FLEXION DURING LANDING IS ASSOCIATED WITH INCREASED FRONTAL PLANE KNEE MOTION AND MOMENTS

PubMed Central

Pollard, Christine D.; Sigward, Susan M.; Powers, Christopher M.

2009-01-01

Background It has been proposed that female athletes who limit knee and hip flexion during athletic tasks rely more on the passive restraints in the frontal plane to deceleration their body center of mass. This biomechanical pattern is thought to increase the risk for anterior cruciate ligament injury. To date, the relationship between sagittal plane kinematics and frontal plane knee motion and moments has not been explored. Methods Subjects consisted of fifty-eight female club soccer players (age range: 11 to 20 years) with no history of knee injury. Kinematics, ground reaction forces, and surface electromyography were collected while each subject performed a drop landing task. Subjects were divided into two groups based on combined sagittal plane knee and hip flexion angles during the deceleration phase of landing (high flexion and low flexion). Findings Subjects in the low flexion group demonstrated increased knee valgus angles (P = 0.02, effect size 0.27), increased knee adductor moments (P = 0.03, effect size 0.24), decreased energy absorption at the knee and hip (P = 0.02, effect size 0.25; and P< 0.001, effect size 0.59), and increased vastus lateralis EMG when compared to subjects in the high flexion group (P = 0.005, effect size 0.35). Interpretation Female athletes with limited sagittal plane motion during landing exhibit a biomechanical profile that may put these individuals at greater risk for anterior cruciate ligament injury. PMID:19913961

The effect of age on sagittal plane profile of the lumbar spine according to standing, supine, and various sitting positions

PubMed Central

2014-01-01

Background The sagittal alignment of the spine changes depending on body posture and degenerative changes. This study aimed to observe changes in sagittal alignment of the lumbar spine with different positions (standing, supine, and various sitting postures) and to verify the effect of aging on lumbar sagittal alignment. Methods Whole-spine lateral radiographs were obtained for young volunteers (25.4 ± 2.3 years) and elderly volunteers (66.7 ± 1.7 years). Radiographs were obtained in standing, supine, and sitting (30°, 60°, and 90°) positions respectively. We compared the radiological changes in the lordotic and segmental angles in different body positions and at different ages. Upper and lower lumbar lordosis were defined according to differences in anatomical sagittal mobility and kinematic behavior. Results Lumbar lordosis was greater in a standing position (52.79° and 53.90° in young and old groups, respectively) and tended to decrease as position changed from supine to sitting. Compared with the younger group, the older group showed significantly more lumbar lordosis in supine and 60° and 90° sitting positions (P = 0.043, 0.002, 0.011). Upper lumbar lordosis in the younger group changed dynamically in all changed positions compared with the old group (P = 0.019). Lower lumbar lordosis showed a decreasing pattern in both age groups, significantly changing as position changed from 30° to 60° (P = 0.007, 0.007). Conclusions Lumbar lordosis decreases as position changes from standing to 90°sitting. The upper lumbar spine is more flexible in individuals in their twenties compared to those in their sixties. Changes in lumbar lordosis were concentrated in the lower lumbar region in the older group in sitting positions. PMID:24571953

Ankle instability.

PubMed

Ferran, Nicholas A; Oliva, Francesco; Maffulli, Nicola

2009-06-01

Acute ankle sprains are common, and if inadequately treated may result in chronic instability. Lateral ankle injuries are most common, with deltoid injuries rare and associated with ankle fractures/dislocation. Medial ankle instability is rare. Functional management of acute lateral ankle sprains is the treatment of choice, with acute ligament repair reserved for athletes. Chronic lateral ankle instability is initially managed conservatively, however, failure of rehabilitation is an indication for surgical management. Nonanatomic tenodesis reconstructions have poor long-term results, sacrifice peroneal tendons, and disrupt normal ankle and hindfoot biomechanics. Anatomic repair of the anterior talofibular and calcaneofibular ligaments is recommended when the quality of the ruptured ligaments permits. Anatomic reconstruction with autograft or allograft should be performed when ligaments are attenuated. The role of arthroscopic reconstruction is evolving. Ankle arthroscopy should be performed at the time of repair or reconstruction and should address any other intra-articular causes of pain.

Evaluation of human dynamic balance in Grassmann manifold

NASA Astrophysics Data System (ADS)

Michalczuk, Agnieszka; Wereszczyński, Kamil; Mucha, Romualda; Świtoński, Adam; Josiński, Henryk; Wojciechowski, Konrad

2017-07-01

The authors present an application of Grassmann manifold to the evaluation of human dynamic balance based on the time series representing movements of hip, knee and ankle joints in the sagittal, frontal and transverse planes. Time series were extracted from gait sequences which were recorded in the Human Motion Laboratory (HML) of the Polish-Japanese Academy of Information Technology in Bytom, Poland using the Vicon system.

Sagittal plane joint kinetics during stair ascent in patients with peripheral arterial disease and intermittent claudication.

PubMed

King, Stephanie L; Vanicek, Natalie; O'Brien, Thomas D

2017-06-01

Stair negotiation poses a substantial physical demand on the musculoskeletal system and this challenging task can place individuals at risk of falls. Peripheral arterial disease (PAD) can cause intermittent claudication (IC) pain in the calf and results in altered gait mechanics during level walking. However, whether those with PAD-IC adopt alternate strategies to climb stairs is unknown. Twelve participants with PAD-IC (six bilateral and six unilateral) and 10 healthy controls were recruited and instructed to ascend a five-step staircase whilst 3D kinematic data of the lower-limbs were recorded synchronously with kinetic data from force plates embedded into the staircase on steps two and three. Limbs from the unilateral group and both limbs from the bilateral claudicants were categorised as claudicating (N=18), asymptomatic (N=6) and control (N=10). Claudicants walked more slowly than healthy controls (trend; P=<0.066). Both claudicating- and asymptomatic-limb groups had reduced propulsive GRF (P=0.025 and P=0.002, respectively) and vertical GRF (P=0.005 and P=0.001, respectively) compared to controls. The claudicating-limb group had a reduced knee extensor moment during forward continuance (P=0.060), ankle angular velocity at peak moment (P=0.039) and ankle power generation (P=0.055) compared to the controls. The slower gait speed, irrespective of laterality of symptoms, indicates functional capacity was determined by the limitations of the claudicating limb. Reduced ankle power generation and angular velocity (despite adequate plantarflexor moment) implies velocity-dependent limitations existed in the calf. The lack of notable compensatory strategies indicates reliance on an impaired muscle group to accomplish this potentially hazardous task, highlighting the importance of maintaining plantarflexor strength and power in those with PAD-IC. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of myofascial release leg pull and sagittal plane isometric contract-relax techniques on passive straight-leg raise angle.

PubMed

Hanten, W P; Chandler, S D

1994-09-01

Experimental evidence does not currently exist to support the claims of clinical effectiveness for myofascial release techniques. This presents an obvious need to document the effects of myofascial release. The purpose of this study was to compare the effects of two techniques, sagittal plane isometric contract-relax and myofascial release leg pull for increasing hip flexion range of motion (ROM) as measured by the angle of passive straight-leg raise. Seventy-five nondisabled, female subjects 18-29 years of age were randomly assigned to contract-relax, leg pull, or control groups. Pretest hip flexion ROM was measured for each subject's right hip with a passive straight-leg raise test using a fluid-filled goniometer. Subjects in the treatment groups received either contract-relax or leg pull treatment applied to the right lower extremity; subjects in the control group remained supine quietly for 5 minutes. Following treatment, posttest straight-leg raise measurements were performed. A one-way analysis of variance followed by a Newman-Keuls post hoc comparison of mean gain scores showed that subjects receiving contract-relax treatment increased their ROM significantly more than those who received leg pull treatment, and the increase in ROM of subjects in both treatment groups was significantly higher than those of the control group. The results suggest that while both contract-relax and leg pull techniques can significantly increase hip flexion ROM in normal subjects, contract-relax treatment may be more effective and efficient than leg pull treatment.

Movement Strategies among Groups of Chronic Ankle Instability, Coper, and Control.

PubMed

Son, S Jun; Kim, Hyunsoo; Seeley, Matthew K; Hopkins, J Ty

2017-08-01

Comprehensive evaluation of movement strategies during functional movement is a difficult undertaking. Because of this challenge, studied movements have been oversimplified. Furthermore, evaluating movement strategies at only a discrete time point(s) provide limited insight into how movement strategies may change or adapt in chronic ankle instability (CAI) patients. This study aimed to identify abnormal movement strategies in individuals with a history of ankle sprain injury during a sports maneuver compared with healthy controls. Sixty-six participants, consisting of 22 CAI patients, 22 ankle sprain copers, and 22 healthy controls, participated in this study. Functional profiles of lower extremity kinematics, kinetics, and EMG activation from initial contact (0% of stance) to toe-off (100% of stance) were collected and analyzed during a jump landing/cutting task using a functional data analysis approach. Compared with copers, CAI patients displayed landing positions of less plantarflexion, less inversion, more knee flexion, more hip flexion, and less hip abduction during the first 25% of stance. However, restricted dorsiflexion angle was observed in both CAI patients and copers relative to controls during the midlanding to mid-side-cutting phase when the ankle and knee reached its peak range of motion (e.g., dorsiflexion and knee flexion). Reduced EMG activation of tibialis anterior, peroneus longus, medial gastrocnemius, and gluteus medius may be due to altered kinematics that reduce muscular demands on the involved muscles. CAI patients displayed altered movement strategies, perhaps in an attempt to avoid perceived positions of risk. Although sagittal joint positions seemed to increase the external torque on the knee and hip extensors, frontal joint positions appeared to reduce the muscular demands on evertor and hip abductor muscles.

Syndesmotic ankle sprain.

PubMed

Childs, Sharon G

2012-01-01

Ankle sprain injuries are the most common type of joint sprain. The prevalence of ankle joint sprains accounts for 21% of joint injuries in the body. Although somewhat rare, high-ankle or syndesmotic ankle sprains occur in up to 15% of ankle trauma. This article will present the pathomechanics of the high-ankle or syndesmotic sprain.

Effect of an ankle-foot orthosis on knee joint mechanics: a novel conservative treatment for knee osteoarthritis.

PubMed

Fantini Pagani, Cynthia H; Willwacher, Steffen; Benker, Rita; Brüggemann, Gert-Peter

2014-12-01

Several conservative treatments for medial knee osteoarthritis such as knee orthosis and laterally wedged insoles have been shown to reduce the load in the medial knee compartment. However, those treatments also present limitations such as patient compliance and inconsistent results regarding the treatment success. To analyze the effect of an ankle-foot orthosis on the knee adduction moment and knee joint alignment in the frontal plane in subjects with knee varus alignment. Controlled laboratory study, repeated measurements. In total, 14 healthy subjects with knee varus alignment were analyzed in five different conditions: without orthotic, with laterally wedged insoles, and with an ankle-foot orthosis in three different adjustments. Three-dimensional kinetic and kinematic data were collected during gait analysis. Significant decreases in knee adduction moment, knee lever arm, and joint alignment in the frontal plane were observed with the ankle-foot orthosis in all three different adjustments. No significant differences could be found in any parameter while using the laterally wedged insoles. The ankle-foot orthosis was effective in reducing the knee adduction moment. The decreases in this parameter seem to be achieved by changing the knee joint alignment and thereby reducing the knee lever arm in the frontal plane. This study presents a novel approach for reducing the load in the medial knee compartment, which could be developed as a new treatment option for patients with medial knee osteoarthritis. © The International Society for Prosthetics and Orthotics 2013.

Ankle sprain (image)

MedlinePlus

An ankle sprain is a common injury to the ankle. The most common way the ankle is injured is when ... swelling, inflammation, and bruising around the ankle. An ankle sprain injury may take a few weeks to many ...

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

Ankle sprain - aftercare

MedlinePlus

Lateral ankle sprain - aftercare; Medial ankle sprain - aftercare; Medial ankle injury - aftercare; Ankle syndesmosis sprain - aftercare; Syndesmosis injury - aftercare; ATFL injury - aftercare; CFL injury - ...

The size of the supraspinatus outlet during elevation of the arm in the frontal and sagittal plane: a 3-D model study.

PubMed

Meskers, Carel G M; van der Helm, Frans C T; Rozing, Piet M

2002-05-01

To quantify the size of the supraspinatus outlet as it is dictated by both the three-dimensional geometry of the shoulder and the relative orientation of the humerus with respect to the scapula during motions of the arm. Previously obtained data of shoulder kinematics were brought into a geometrical model of the shoulder, derived from a cadaver study. Knowledge of the parameters dictating the size of the supraspinatus outlet is essential for a better understanding of the impingement syndrome of the shoulder. A geometrical model, based on fitting spheres to various anatomical items of the shoulder was derived from three-dimensional position data of the gleno-humeral joint and coraco-acromial arch of 32 cadaver shoulders. Kinematical data were collected from 10 healthy volunteers. The geometrical and kinematical data were combined to study the supraspinatus outlet during elevation of the humerus in the frontal and sagittal plane. No single geometry parameter correlated significantly with the initial size of the outlet. During arm elevation, the greater tuberosity was moved away from the coraco-acromial arch quite effectively resulting in narrowing of the outlet during elevation in the frontal plane from 60 degrees to 120 degrees only. Deviations from the average were quite substantial. This was caused by kinematical and especially geometrical variability. The size of the outlet is dictated by both the geometry and kinematics of the gleno-humeral joint. Assessment of the individual susceptibility to impingement requires three-dimensional viewing techniques including three-dimensional movements of both the scapula and humerus. Little is known about etiology and pathogenesis of various shoulder disorders such as the impingement syndrome. The supraspinatus outlet plays probably a key role. More knowledge on the architecture of the outlet is required for a better understanding.

Ankle Arthroscopic Reconstruction of Lateral Ligaments (Ankle Anti-ROLL)

PubMed Central

Takao, Masato; Glazebrook, Mark; Stone, James; Guillo, Stéphane

2015-01-01

Ankle instability is a condition that often requires surgery to stabilize the ankle joint that will improve pain and function if nonoperative treatments fail. Ankle stabilization surgery may be performed as a repair in which the native existing anterior talofibular ligament or calcaneofibular ligament (or both) is imbricated or reattached. Alternatively, when native ankle ligaments are insufficient for repair, a reconstruction of the ligaments may be performed in which an autologous or allograft tendon is used to reconstruct the anterior talofibular ligament or calcaneofibular ligament (or both). Currently, ankle stabilization surgery is most commonly performed through an open incision, but arthroscopic ankle stabilization using repair techniques has been described and is being used more often. We present our technique for anatomic ankle arthroscopic reconstruction of the lateral ligaments (anti-ROLL) performed in an all–inside-out manner that is likely safe for patients and minimally invasive. PMID:26900560

Musculoskeletal modelling of human ankle complex: Estimation of ankle joint moments.

PubMed

Jamwal, Prashant K; Hussain, Shahid; Tsoi, Yun Ho; Ghayesh, Mergen H; Xie, Sheng Quan

2017-05-01

A musculoskeletal model for the ankle complex is vital in order to enhance the understanding of neuro-mechanical control of ankle motions, diagnose ankle disorders and assess subsequent treatments. Motions at the human ankle and foot, however, are complex due to simultaneous movements at the two joints namely, the ankle joint and the subtalar joint. The musculoskeletal elements at the ankle complex, such as ligaments, muscles and tendons, have intricate arrangements and exhibit transient and nonlinear behaviour. This paper develops a musculoskeletal model of the ankle complex considering the biaxial ankle structure. The model provides estimates of overall mechanical characteristics (motion and moments) of ankle complex through consideration of forces applied along ligaments and muscle-tendon units. The dynamics of the ankle complex and its surrounding ligaments and muscle-tendon units is modelled and formulated into a state space model to facilitate simulations. A graphical user interface is also developed during this research in order to include the visual anatomical information by converting it to quantitative information on coordinates. Validation of the ankle model was carried out by comparing its outputs with those published in literature as well as with experimental data obtained from an existing parallel ankle rehabilitation robot. Qualitative agreement was observed between the model and measured data for both, the passive and active ankle motions during trials in terms of displacements and moments. Copyright © 2017 Elsevier Ltd. All rights reserved.

3D knee segmentation based on three MRI sequences from different planes.

PubMed

Zhou, L; Chav, R; Cresson, T; Chartrand, G; de Guise, J

2016-08-01

In clinical practice, knee MRI sequences with 3.5~5 mm slice distance in sagittal, coronal, and axial planes are often requested for the knee examination since its acquisition is faster than high-resolution MRI sequence in a single plane, thereby reducing the probability of motion artifact. In order to take advantage of the three sequences from different planes, a 3D segmentation method based on the combination of three knee models obtained from the three sequences is proposed in this paper. In the method, the sub-segmentation is respectively performed with sagittal, coronal, and axial MRI sequence in the image coordinate system. With each sequence, an initial knee model is hierarchically deformed, and then the three deformed models are mapped to reference coordinate system defined by the DICOM standard and combined to obtain a patient-specific model. The experimental results verified that the three sub-segmentation results can complement each other, and their integration can compensate for the insufficiency of boundary information caused by 3.5~5 mm gap between consecutive slices. Therefore, the obtained patient-specific model is substantially more accurate than each sub-segmentation results.

Gait patterns in hemiplegic patients with equinus foot deformity.

PubMed

Manca, M; Ferraresi, G; Cosma, M; Cavazzuti, L; Morelli, M; Benedetti, M G

2014-01-01

Equinus deformity of the foot is a common feature of hemiplegia, which impairs the gait pattern of patients. The aim of the present study was to explore the role of ankle-foot deformity in gait impairment. A hierarchical cluster analysis was used to classify the gait patterns of 49 chronic hemiplegic patients with equinus deformity of the foot, based on temporal-distance parameters and joint kinematic measures obtained by an innovative protocol for motion assessment in the sagittal, frontal, and transverse planes, synthesized by parametrical analysis. Cluster analysis identified five subgroups of patients with homogenous levels of dysfunction during gait. Specific joint kinematic abnormalities were found, according to the speed of progression in each cluster. Patients with faster walking were those with less ankle-foot complex impairment or with reduced range of motion of ankle-foot complex, that is with a stiff ankle-foot complex. Slow walking was typical of patients with ankle-foot complex instability (i.e., larger motion in all the planes), severe equinus and hip internal rotation pattern, and patients with hip external rotation pattern. Clustering of gait patterns in these patients is helpful for a better understanding of dysfunction during gait and delivering more targeted treatment.

Optimal Control Based Stiffness Identification of an Ankle-Foot Orthosis Using a Predictive Walking Model

PubMed Central

Sreenivasa, Manish; Millard, Matthew; Felis, Martin; Mombaur, Katja; Wolf, Sebastian I.

2017-01-01

Predicting the movements, ground reaction forces and neuromuscular activity during gait can be a valuable asset to the clinical rehabilitation community, both to understand pathology, as well as to plan effective intervention. In this work we use an optimal control method to generate predictive simulations of pathological gait in the sagittal plane. We construct a patient-specific model corresponding to a 7-year old child with gait abnormalities and identify the optimal spring characteristics of an ankle-foot orthosis that minimizes muscle effort. Our simulations include the computation of foot-ground reaction forces, as well as the neuromuscular dynamics using computationally efficient muscle torque generators and excitation-activation equations. The optimal control problem (OCP) is solved with a direct multiple shooting method. The solution of this problem is physically consistent synthetic neural excitation commands, muscle activations and whole body motion. Our simulations produced similar changes to the gait characteristics as those recorded on the patient. The orthosis-equipped model was able to walk faster with more extended knees. Notably, our approach can be easily tuned to simulate weakened muscles, produces physiologically realistic ground reaction forces and smooth muscle activations and torques, and can be implemented on a standard workstation to produce results within a few hours. These results are an important contribution toward bridging the gap between research methods in computational neuromechanics and day-to-day clinical rehabilitation. PMID:28450833

Expecting ankle tilts and wearing an ankle brace influence joint control in an imitated ankle sprain mechanism during walking.

PubMed

Gehring, Dominic; Wissler, Sabrina; Lohrer, Heinz; Nauck, Tanja; Gollhofer, Albert

2014-03-01

A thorough understanding of the functional aspects of ankle joint control is essential to developing effective injury prevention. It is of special interest to understand how neuromuscular control mechanisms and mechanical constraints stabilize the ankle joint. Therefore, the aim of the present study was to determine how expecting ankle tilts and the application of an ankle brace influence ankle joint control when imitating the ankle sprain mechanism during walking. Ankle kinematics and muscle activity were assessed in 17 healthy men. During gait rapid perturbations were applied using a trapdoor (tilting with 24° inversion and 15° plantarflexion). The subjects either knew that a perturbation would definitely occur (expected tilts) or there was only the possibility that a perturbation would occur (potential tilts). Both conditions were conducted with and without a semi-rigid ankle brace. Expecting perturbations led to an increased ankle eversion at foot contact, which was mediated by an altered muscle preactivation pattern. Moreover, the maximal inversion angle (-7%) and velocity (-4%), as well as the reactive muscle response were significantly reduced when the perturbation was expected. While wearing an ankle brace did not influence muscle preactivation nor the ankle kinematics before ground contact, it significantly reduced the maximal ankle inversion angle (-14%) and velocity (-11%) as well as reactive neuromuscular responses. The present findings reveal that expecting ankle inversion modifies neuromuscular joint control prior to landing. Although such motor control strategies are weaker in their magnitude compared with braces, they seem to assist ankle joint stabilization in a close-to-injury situation. Copyright © 2013 Elsevier B.V. All rights reserved.

Effects of ankle-foot orthoses on mediolateral foot-placement ability during post-stroke gait.

PubMed

Zissimopoulos, Angelika; Fatone, Stefania; Gard, Steven

2015-10-01

Accurate and precise mediolateral foot placement is important for balance during gait, but is impaired post stroke. Mediolateral foot placement may be improved with ankle-foot orthosis use. The purpose of this study was to determine whether an ankle-foot orthosis improves mediolateral foot-placement ability during post-stroke ambulation. Crossover trial with randomized order of conditions tested. The accuracy and precision of mediolateral foot placement was quantified while subjects targeted four different randomized step widths. Subjects were tested with and without their regular non-rigid ankle-foot orthosis in two separate visits (order randomized). While ankle-foot orthosis use corrected foot and ankle alignment (i.e. significantly decreased mid-swing plantar flexion, p = 0.000), effects of ankle-foot orthosis use on hip hiking (p = 0.545), circumduction (p = 0.179), coronal plane hip range of motion (p = 0.06), and mediolateral foot-placement ability (p = 0.537) were not significant. While ankle-foot orthosis-mediated equinovarus correction of the affected foot and ankle was not associated with improved biomechanics of walking (i.e. proximal ipsilateral hip kinematics or mediolateral foot-placement ability), it may affect other aspects of balance that were not tested in this study (e.g. proprioception, cerebellar, vestibular, and cognitive mechanisms). Studies that investigate the effect of ankle-foot orthosis on gait can help advance stroke rehabilitation by documenting the specific gait benefits of ankle-foot orthosis use. In this study, we investigated the effect of ankle-foot orthosis use on mediolateral foot-placement ability, an aspect of gait important for maintaining balance. © The International Society for Prosthetics and Orthotics 2014.

Kinematic Adaptations of Forward And Backward Walking on Land and in Water

PubMed Central

Cadenas-Sanchez, Cristina; Arellano, Raúl; Vanrenterghem, Jos; López-Contreras, Gracia

2015-01-01

The aim of this study was to compare sagittal plane lower limb kinematics during walking on land and submerged to the hip in water. Eight healthy adults (age 22.1 ± 1.1 years, body height 174.8 ± 7.1 cm, body mass 63.4 ± 6.2 kg) were asked to cover a distance of 10 m at comfortable speed with controlled step frequency, walking forward or backward. Sagittal plane lower limb kinematics were obtained from three dimensional video analysis to compare spatiotemporal gait parameters and joint angles at selected events using two-way repeated measures ANOVA. Key findings were a reduced walking speed, stride length, step length and a support phase in water, and step length asymmetry was higher compared to the land condition (p<0.05). At initial contact, knees and hips were more flexed during walking forward in water, whilst, ankles were more dorsiflexed during walking backward in water. At final stance, knees and ankles were more flexed during forward walking, whilst the hip was more flexed during backward walking. These results show how walking in water differs from walking on land, and provide valuable insights into the development and prescription of rehabilitation and training programs. PMID:26839602

Can Chronic Ankle Instability be Prevented? Rethinking Management of Lateral Ankle Sprains.

ERIC Educational Resources Information Center

Denegar, Craig R.; Miller, Sayers J., III

2002-01-01

Investigates whether chronic ankle instability can be prevented, discussing: the relationship between mechanical and functional instability; normal ankle mechanics, sequelae to lateral ankle sprains, and abnormal ankle mechanics; and tissue healing, joint dysfunction, and acute lateral ankle sprain management. The paper describes a treatment model…

Open ankle arthrodeses via an anterior approach.

PubMed

Gordon, David; Zicker, Robyn; Cullen, Nicholas; Singh, Dishan

2013-03-01

In open ankle arthrodesis, debate remains as to which surgical approach and fixation devices should be used. The purpose of this study was to identify union, complication, and patient satisfaction rates of ankle fusions performed at our institution, using the plane between extensor hallucis longus and tibialis anterior with medial tibiotalar screw internal fixation. A retrospective review was performed of all isolated primary fusions between 2005 and 2009. Eighty-two ankles were identified in 73 patients. All patient records were reviewed, and 57 patients (65 ankles) attended for clinical evaluation and scoring. Age range at surgery was 18 to 75 years (mean, 56.1 years); 8 patients were smokers. Diagnoses were trauma in 52 patients (63%), osteoarthritis in 17, rheumatoid arthritis in 7, Charcot-Marie-Tooth disease in 3, congenital talipes equinovarus in 2, and talar avascular necrosis in 1. Follow-up range was 7 months to 8.3 years (mean, 4 years). Time to union ranged from 8 to 39 weeks (mean, 13.3) with a union rate of 100%. The AOFAS range was 12 to 93 (mean, 70). Eighty percent were "very satisfied" or "satisfied." Major complication rate was 14.6%: 7 malalignments; 3 wound problems; 2 complex regional pain syndrome; and 2 delayed unions, both smokers. An excellent union rate, high patient satisfaction, and low complication rate were achieved with this technique. Varus malalignment and persistent pain resulted in dissatisfaction. Many patients remained highly active, and bilaterally fused patients functioned as well as unilateral ones. Level IV, retrospective case series.

Changes in ankle joint motion after Supramalleolar osteotomy: a cadaveric model.

PubMed

Kim, Hak Jun; Yeo, Eui Dong; Rhyu, Im Joo; Lee, Soon-Hyuck; Lee, Yeon Soo; Lee, Young Koo

2017-09-09

Malalignment of the ankle joint has been found after trauma, by neurological disorders, genetic predisposition and other unidentified factors, and results in asymmetrical joint loading. For a medial open wedge supramalleolar osteotomy(SMO), there are some debates as to whether concurrent fibular osteotomy should be performed. We assessed the changes in motion of ankle joint and plantar pressure after supramalleolar osteotomy without fibular osteotomy. Ten lower leg specimens below the knee were prepared from fresh-frozen human cadavers. They were harvested from five males (10 ankles)whose average age was 70 years. We assessed the motion of ankle joint as well as plantar pressure for SS(supra-syndesmotic) SMO and IS(intra-syndesmotic) SMO. After the osteotomy, each specimen was subjected to axial compression from 20 N preload to 350 N representing half-body weight. For the measurement of the motion of ankle joint, the changes in gap and point, angles in ankle joint were measured. The plantar pressure were also recorded using TekScan sensors. The changes in the various gap, point, and angles movements on SS-SMO and IS-SMO showed no statistically significant differences between the two groups. Regarding the shift of plantar center of force (COF) were noted in the anterolateral direction, but not statistically significant. SS-SMO and IS-SMO with intact fibula showed similar biomechanical effect on the ankle joint. We propose that IS-SMO should be considered carefully for the treatment of osteoarthrosis when fibular osteotomy is not performed because lateral cortex fracture was less likely using the intrasyndesmosis plane because of soft tissue support.

Soreness-related changes in three-dimensional running biomechanics following eccentric knee extensor exercise.

PubMed

Paquette, Max R; Peel, Shelby A; Schilling, Brian K; Melcher, Dan A; Bloomer, Richard J

2017-06-01

Runners often experience delayed onset muscle soreness (DOMS), especially of the knee extensors, following prolonged running. Sagittal knee joint biomechanics are altered in the presence of knee extensor DOMS but it is unclear how muscle soreness affects lower limb biomechanics in other planes of motion. The purpose of this study was to assess the effects of knee extensor DOMS on three-dimensional (3D) lower limb biomechanics during running. Thirty-three healthy men (25.8 ± 6.8 years; 84.1 ± 9.2 kg; 1.77 ± 0.07 m) completed an isolated eccentric knee extensor damaging protocol to elicit DOMS. Biomechanics of over-ground running at a set speed of 3.35 m s -1 ±5% were measured before eccentric exercise (baseline) and, 24 h and 48 h following exercise in the presence of knee extensor DOMS. Knee flexion ROM was reduced at 48 h (P = 0.01; d = 0.26), and peak knee extensor moment was reduced at 24 h (P = 0.001; d = 0.49) and 48 h (P < 0.001; d = 0.68) compared to baseline. Frontal and transverse plane biomechanics were unaffected by the presence of DOMS (P > 0.05). Peak positive ankle and knee joint powers and, peak negative knee joint power were all reduced from baseline to 24 h and 48 h (P < 0.05). These findings suggest that knee extensor DOMS greatly influences sagittal knee joint angular kinetics and, reduces sagittal power production at the ankle joint. However, knee extensor DOMS does not affect frontal and transverse plane lower limb joint biomechanics during running.

Control of acceleration during sudden ankle supination in people with unstable ankles.

PubMed

Vaes, P; Van Gheluwe, B; Duquet, W

2001-12-01

Comparative study of differences in functional control during ankle supination in the standing position in matched stable and unstable ankles (ex post facto design). To document acceleration and deceleration during ankle supination in the standing position and to determine differences in control of supination perturbation between stable and unstable ankles. Repetitive ankle sprain can be explained by mechanical instability only in a minority of cases. Exercise therapy for ankle instability is based on clinical experience. Joint stability has not yet been measured in dynamic situations that are similar to the situations leading to a traumatic sprain. The process of motor control during accelerating ankle supination has not been adequately addressed in the literature. Patients with complaints of ankle instability (16 unstable ankles) and nonimpaired controls (18 stable ankles) were examined (N = 17 subjects, 10 women and 7 men). The average age was 23.7 +/- 5.0 years (range, 20-41 y). Control of supination speed was studied during 50 degrees of ankle supination in the standing position using accelerometry (total supination time and deceleration times) and electromyography (latency time). Timing of motor response was estimated by measuring electromechanical delay. The presence of an early, sudden, and presumably passive slowdown of ankle supination in the standing position was observed. Peroneal muscle motor response was detected before the end of the supination. Unstable ankles showed significantly shorter total supination time (109.3 ms versus 124.1 ms) and significantly longer latency time (58.9 ms versus 47.7 ms). Functional control in unstable ankles is less efficient in decelerating the ankle during the supination test procedures used in our study. Our conclusions are based on significantly faster total supination and significantly slower electromyogram response in unstable ankles. The results support the hypothesis that both decelerating the total supination

Impaired control of weight bearing ankle inversion in subjects with chronic ankle instability.

PubMed

Terrier, R; Rose-Dulcina, K; Toschi, B; Forestier, N

2014-04-01

Previous studies have proposed that evertor muscle weakness represents an important factor affecting chronic ankle instability. For research purposes, ankle evertor strength is assessed by means of isokinetic evaluations. However, this methodology is constraining for daily clinical use. The present study proposes to assess ankle evertor muscle weakness using a new procedure, one that is easily accessible for rehabilitation specialists. To do so, we compared weight bearing ankle inversion control between patients suffering from chronic ankle instability and healthy subjects. 12 healthy subjects and 11 patients suffering from chronic ankle instability conducted repetitions of one leg weight bearing ankle inversion on a specific ankle destabilization device equipped with a gyroscope. Ankle inversion control was performed by means of an eccentric recruitment of evertor muscles. Instructions were to perform, as slow as possible, the ankle inversion while resisting against full body weight applied on the tested ankle. Data clearly showed higher angular inversion velocity peaks in patients suffering from chronic ankle instability. This illustrates an impaired control of weight bearing ankle inversion and, by extension, an eccentric weakness of evertor muscles. The present study supports the hypothesis of a link between the decrease of ankle joint stability and evertor muscle weakness. Moreover, it appears that the new parameter is of use in a clinical setting. Copyright © 2014 Elsevier Ltd. All rights reserved.

Is the sagittal postural alignment different in normal and dysphonic adult speakers?

PubMed

Franco, Débora; Martins, Fernando; Andrea, Mário; Fragoso, Isabel; Carrão, Luís; Teles, Júlia

2014-07-01

Clinical research in the field of voice disorders, in particular functional dysphonia, has suggested abnormal laryngeal posture due to muscle adaptive changes, although specific evidence regarding body posture has been lacking. The aim of our study was to verify if there were significant differences in sagittal spine alignment between normal (41 subjects) and dysphonic speakers (33 subjects). Cross-sectional study. Seventy-four adults, 35 males and 39 females, were submitted to sagittal plane photographs so that spine alignment could be analyzed through the Digimizer-MedCalc Software Ltd program. Perceptual and acoustic evaluation and nasoendoscopy were used for dysphonic judgments: normal and dysphonic speakers. For thoracic length curvature (TL) and for the kyphosis index (KI), a significant effect of dysphonia was observed with mean TL and KI significantly higher for the dysphonic speakers than for the normal speakers. Concerning the TL variable, a significant effect of sex was found, in which the mean of the TL was higher for males than females. The interaction between dysphonia and sex did not have a significant effect on TL and KI variables. For the lumbar length curvature variable, a significant main effect of sex was demonstrated; there was no significant main effect of dysphonia or significant sex×dysphonia interaction. Findings indicated significant differences in some sagittal spine posture measures between normal and dysphonic speakers. Postural measures can add useful information to voice assessment protocols and should be taken into account when considering particular treatment strategies. Copyright © 2014 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

FIBRE AND INTEGRATED OPTICS. OPTICAL PROCESSING OF INFORMATION: Intrafibre rotation of the plane of polarisation

NASA Astrophysics Data System (ADS)

Zel'dovich, Boris Ya; Kundikova, N. D.

1995-02-01

Rotation of the plane of polarisation during propagation of sagittal rays in a rectilinear multimode fibre was observed experimentally. The angle of rotation was in good agreement with the results predicted on the basis of the Rytov—Vladimirskii—Berry theory.

Efficacy of an ankle brace with a subtalar locking system in inversion control in dynamic movements.

PubMed

Zhang, Songning; Wortley, Michael; Chen, Qingjian; Freedman, Julia

2009-12-01

Controlled laboratory study. To examine effectiveness of an ankle brace with a subtalar locking system in restricting ankle inversion during passive and dynamic movements. Semirigid ankle braces are considered more effective in restricting ankle inversion than other types of brace, but a semirigid brace with a subtalar locking system may be even more effective. Nineteen healthy subjects with no history of major lower extremity injuries were included in the study. Participants performed 5 trials of an ankle inversion drop test and a lateral-cutting movement without wearing a brace and while wearing either the Element (with the subtalar locking system), a Functional ankle brace, or an ASO ankle brace. A 2-way repeated-measures analysis of variance (ANOVA) was used to assess brace differences (P?.05). All 3 braces significantly reduced total passive ankle frontal plane range of motion (ROM), with the Element ankle brace being the most effective. For the inversion drop the results showed significant reductions in peak ankle inversion angle and inversion ROM for all 3 braces compared to the no brace condition; and the peak inversion velocity was also reduced for the Element brace and the Functional brace. In the lateral-cutting movement, a small but significant reduction of the peak inversion angle in early foot contact and the peak eversion velocity at push-off were seen when wearing the Element and the Functional ankle braces compared to the no brace condition. Peak vertical ground reaction force was reduced for the Element brace compared to the ASO brace and the no brace conditions. These results suggest that the tested ankle braces, especially the Element brace, provided effective restriction of ankle inversion during both passive and dynamic movements.

The effect of dual tasking on foot kinematics in people with functional ankle instability.

PubMed

Tavakoli, Sanam; Forghany, Saeed; Nester, Christopher

2016-09-01

Some cases of repeated inversion ankle sprains are thought to have a neurological basis and are termed functional ankle instability (FAI). In addition to factors local to the ankle, such as loss of proprioception, cognitive demands have the ability to influence motor control and may increase the risk of repetitive lateral sprains. The purpose of this study was to investigate the effect of cognitive demand on foot kinematics in physically active people with functional ankle instability. 21 physically active participants with FAI and 19 matched healthy controls completed trials of normal walking (single task) and normal walking while performing a cognitive task (dual task). Foot motion relative to the shank was recorded. Cognitive performance, ankle kinematics and movement variability in single and dual task conditions was characterized. During normal walking, the ankle joint was significantly more inverted in FAI compared to the control group pre and post initial contact. Under dual task conditions, there was a statistically significant increase in frontal plane foot movement variability during the period 200ms pre and post initial contact in people with FAI compared to the control group (p<0.05). Dual task also significantly increased plantar flexion and inversion during the period 200ms pre and post initial contact in the FAI group (p<0.05). participants with FAI demonstrated different ankle movement patterns and increased movement variability during a dual task condition. Cognitive load may increase risk of ankle instability in these people. Copyright © 2016 Elsevier B.V. All rights reserved.

Isolated syndesmosis ankle injury.

PubMed

Valkering, Kars P; Vergroesen, Diederik A; Nolte, Peter A

2012-12-01

Isolated syndesmosis injuries often go unrecognized and are diagnosed as lateral ankle sprains; however, they are more disabling than lateral ankle sprains. The reported incidence of isolated syndesmosis injuries in acute ankle sprains ranges between 1% and 16%. When ankle disability lasts for more than 2 months after an ankle sprain, the incidence increases to 23.6%. Diagnostic workup may include stress radiographs, magnetic resonance imaging, or diagnostic arthroscopy. A simple stress test radiograph may reveal an unstable grade III syndesmosis sprain that may go unrecognized on plain anteroposterior and mortise or lateral radiographs of the ankle. The duration of symptoms in isolated syndesmosis injury is longer and more severe, often leading to chronic symptoms or ankle instability requiring operative stabilization.This article describes the clinical presentation, injury classification, and operative stabilization techniques of isolated syndesmosis injuries. The authors performed their preferred operative stabilization technique for isolated syndesmosis injury-arthroscopic debridement of the ankle with syndesmotic stabilization with a syndesmotic screw-in 4 patients. All patients were evaluated 1 year postoperatively with subjective and objective assessment scales. Three of 4 patients showed good improvement of general subjective ankle symptoms and subjective ankle instability rating and a high Sports Ankle Rating System score after 1 year. Copyright 2012, SLACK Incorporated.

Influence of ankle joint plantarflexion and dorsiflexion on lateral ankle sprain: A computational study.

PubMed

Purevsuren, Tserenchimed; Kim, Kyungsoo; Batbaatar, Myagmarbayar; Lee, SuKyoung; Kim, Yoon Hyuk

2018-05-01

Understanding the mechanism of injury involved in lateral ankle sprain is essential to prevent injury, to establish surgical repair and reconstruction, and to plan reliable rehabilitation protocols. Most studies for lateral ankle sprain posit that ankle inversion, internal rotation, and plantarflexion are involved in the mechanism of injury. However, recent studies indicated that ankle dorsiflexion also plays an important role in the lateral ankle sprain mechanism. In this study, the contributions of ankle plantarflexion and dorsiflexion on the ankle joint were evaluated under complex combinations of internal and inversion moments. A multibody ankle joint model including 24 ligaments was developed and validated against two experimental cadaveric studies. The effects of ankle plantarflexion (up to 60°) and dorsiflexion (up to 30°) on the lateral ankle sprain mechanism under ankle inversion moment coupled with internal rotational moment were investigated using the validated model. Lateral ankle sprain injuries can occur during ankle dorsiflexion, in which the calcaneofibular ligament and anterior talofibular ligament tears may occur associated with excessive inversion and internal rotational moment, respectively. Various combinations of inversion and internal moment may lead to anterior talofibular ligament injuries at early ankle plantarflexion, while the inversion moment acts as a primary factor to tear the anterior talofibular ligament in early plantarflexion. It is better to consider inversion and internal rotation as primary factors of the lateral ankle sprain mechanism, while plantarflexion or dorsiflexion can be secondary factor. This information will help to clarify the lateral ankle sprain mechanism of injury.

Preparatory co-activation of the ankle muscles may prevent ankle inversion injuries

PubMed Central

DeMers, Matthew S.; Hicks, Jennifer L.; Delp, Scott L.

2018-01-01

Ankle inversion sprains are the most frequent acute musculoskeletal injuries occurring in physical activity. Interventions that retrain muscle coordination have helped rehabilitate injured ankles, but it is unclear which muscle coordination strategies, if any, can prevent ankle sprains. The purpose of this study was to determine whether coordinated activity of the ankle muscles could prevent excessive ankle inversion during a simulated landing on a 30-degree incline. We used a set of musculoskeletal simulations to evaluate the efficacy of two strategies for coordinating the ankle evertor and invertor muscles during simulated landing scenarios: planned co-activation and stretch reflex activation with physiologic latency (60-millisecond delay). A full-body musculoskeletal model of landing was used to generate simulations of a subject dropping onto an inclined surface with each coordination condition. Within each condition, the intensity of evertor and invertor co-activity or stretch reflexes were varied systematically. The simulations revealed that strong preparatory co-activation of the ankle evertors and invertors prior to ground contact prevented ankle inversion from exceeding injury thresholds by rapidly generating eversion moments after initial contact. Conversely, stretch reflexes were too slow to generate eversion moments before the simulations reached the threshold for inversion injury. These results suggest that training interventions to protect the ankle should focus on stiffening the ankle with muscle co-activation prior to landing. The musculoskeletal models, controllers, software, and simulation results are freely available online at http://simtk.org/home/ankle-sprains, enabling others to reproduce the results and explore new injury scenarios and interventions. PMID:28057351

Correction of antebrachial angulation-rotation deformities in dogs with oblique plane inclined osteotomies.

PubMed

Franklin, Samuel P; Dover, Ryan K; Andrade, Natalia; Rosselli, Desiree; M Clarke, Kevin

2017-11-01

To describe oblique plane inclined osteotomies and report preliminary data on outcomes in dogs treated for antebrachial angulation-rotation deformities. Retrospective clinical study. Six antebrachii from 5 dogs. Records of dogs with antebrachial angulation-rotation deformities treated with oblique plane inclined osteotomies were reviewed. Postoperative frontal, sagittal, and transverse plane alignments were assessed subjectively, and alignment in the frontal and sagittal planes was quantified on radiographs. Outcomes were classified based on owner's and veterinarian's evaluation as full, acceptable, and unacceptable function. Complications were classified as minor, major, or catastrophic. Limb alignment was subjectively considered excellent in 1 case, good in 3 cases, and fair in 2 cases. Osseous union was achieved in all cases (mean 10.5 weeks; range, 6-13 weeks). Outcomes were assessed by the veterinarian as return to full function in 5 cases and acceptable function in 1 case at the final in-hospital follow-up (mean 44 weeks; range, 6-124 weeks). All owners classified their dogs as returning to full function at the final phone/email interview (mean 107 weeks; range, 72-153 weeks). Implants were removed due to infection or irritation in 3/6 limbs, while the other 3 limbs had minor dermatitis secondary to postoperative external coaptation. No catastrophic complications occurred. Oblique plane inclined osteotomies led to a successful outcome in all 6 limbs, but the technique can be challenging and does not always lead to optimal alignment. Future refinement of this technique could focus on the development of patient-specific osteotomy guides to improve accuracy and precision. © 2017 The American College of Veterinary Surgeons.

Biomechanical evaluation of sagittal maxillary internal distraction osteogenesis in unilateral cleft lip and palate patient and noncleft patients: a three-dimensional finite element analysis.

PubMed

Olmez, Sultan; Dogan, Servet; Pekedis, Mahmut; Yildiz, Hasan

2014-09-01

To compare the pattern and amount of stress and displacement during maxillary sagittal distraction osteogenesis (DO) between a patient with unilateral cleft lip and palate (UCLP) and a noncleft patient. Three-dimensional finite element models for both skulls were constructed. Displacements of the surface landmarks and stress distributions in the circummaxillary sutures were analyzed after an anterior displacement of 6 mm was loaded to the elements where the inferior plates of the distractor were assumed to be fixed and were below the Le Fort I osteotomy line. In sagittal plane, more forward movement was found on the noncleft side in the UCLP model (-6.401 mm on cleft side and -6.651 mm on noncleft side for the central incisor region). However, similar amounts of forward movement were seen in the control model. In the vertical plane, a clockwise rotation occurred in the UCLP model, whereas a counterclockwise rotation was seen in the control model. The mathematical UCLP model also showed higher stress values on the sutura nasomaxillaris, frontonasalis, and zygomatiomaxillaris on the cleft side than on the normal side. Not only did the sagittal distraction forces produce advancement forces at the intermaxillary sutures, but more stress was also present on the sutura nasomaxillaris, sutura frontonasalis, and sutura zygomaticomaxillaris on the cleft side than on the noncleft side.

Chronic ankle instability: Current perspectives

PubMed Central

Al-Mohrej, Omar A.; Al-Kenani, Nader S.

2016-01-01

Ankle sprain is reported to be among the most common recurrent injuries. About 20% of acute ankle sprain patients develop chronic ankle instability. The failure of functional rehabilitation after acute ankle sprain leads to the development of chronic ankle instability. Differentiation between functional and anatomical ankle instability is very essential to guide the proper treatment. Stability testing by varus stress test and anterior drawer test should be carried out. Subtalar instability is an important pathology that is commonly by passed during the assessment of chronic ankle instability. Unlike acute ankle sprain, chronic ankle instability might require surgical intervention. The surgical and conservative management options can be very much developed by in-depth knowledge of the ankle anatomy, biomechanics, and pathology. Anatomical repair, augmentation by tendon, or both are the basic methods of surgical intervention. Arthroscopy is becoming more popular in the management of chronic ankle instability. PMID:27843798

Triceps surae muscle-tendon unit length changes as a function of ankle joint angles and contraction levels: the effect of foot arch deformation.

PubMed

Iwanuma, Soichiro; Akagi, Ryota; Hashizume, Satoru; Kanehisa, Hiroaki; Yanai, Toshimasa; Kawakami, Yasuo

2011-09-23

The purpose of this study was to clarify how foot deformation affects the relationship between triceps surae muscle-tendon unit (MTU) length and ankle joint angle. For six women and six men a series of sagittal magnetic resonance (MR) images of the right foot were taken, and changes in MTU length (the displacement of the calcaneal tuberosity), foot arch angle, and ankle joint angle were measured. In the passive session, each subject's ankle joint was secured at 10° dorsiflexed position, neutral position (NP), and 10° and 20° plantar flexed positions while MR images were acquired. In the active session, each subject was requested to perform submaximal isometric plantar flexions (30%, 60%, and 80% of voluntary maximum) at NP. The changes in MTU length in each trial were estimated by two different formulae reported previously. The changes of the measured MTU length as a function of ankle joint angles observed in all trials of the active session were significantly (p<0.05) larger than corresponding values in the passive session and by the estimation formulae. In the passive session, MTU length changes were significantly smaller than the estimated values when the ankle was plantar flexed. The foot arch angle increased as the contraction level increased from rest (117 ± 4°) to 80% (125 ± 3°), and decreased as the ankle was positioned further into plantar flexion in the passive session (115 ± 3°). These results indicate that foot deformation profoundly affects the triceps surae MTU length-ankle joint angle relationship during plantar flexion. Copyright © 2011 Elsevier Ltd. All rights reserved.

Clinical tests of ankle plantarflexor strength do not predict ankle power generation during walking.

PubMed

Kahn, Michelle; Williams, Gavin

2015-02-01

The aim of this study was to investigate the relationship between a clinical test of ankle plantarflexor strength and ankle power generation (APG) at push-off during walking. This is a prospective cross-sectional study of 102 patients with traumatic brain injury. Handheld dynamometry was used to measure ankle plantarflexor strength. Three-dimensional gait analysis was performed to quantify ankle power generation at push-off during walking. Ankle plantarflexor strength was only moderately correlated with ankle power generation at push-off (r = 0.43, P < 0.001; 95% confidence interval, 0.26-0.58). There was also a moderate correlation between ankle plantarflexor strength and self-selected walking velocity (r = 0.32, P = 0.002; 95% confidence interval, 0.13-0.48). Handheld dynamometry measures of ankle plantarflexor strength are only moderately correlated with ankle power generation during walking. This clinical test of ankle plantarflexor strength is a poor predictor of calf muscle function during gait in people with traumatic brain injury.

Ankle-Dorsiflexion Range of Motion After Ankle Self-Stretching Using a Strap

PubMed Central

Jeon, In-cheol; Kwon, Oh-yun; Yi, Chung-Hwi; Cynn, Heon-Seock; Hwang, Ui-jae

2015-01-01

Context  A variety of ankle self-stretching exercises have been recommended to improve ankle-dorsiflexion range of motion (DFROM) in individuals with limited ankle dorsiflexion. A strap can be applied to stabilize the talus and facilitate anterior glide of the distal tibia at the talocrural joint during ankle self-stretching exercises. Novel ankle self-stretching using a strap (SSS) may be a useful method of improving ankle DFROM. Objective  To compare the effects of 2 ankle-stretching techniques (static stretching versus SSS) on ankle DFROM. Design  Randomized controlled clinical trial. Setting  University research laboratory. Patients or Other Participants  Thirty-two participants with limited active dorsiflexion (<20°) while sitting (14 women and 18 men) were recruited. Main Outcome Measure(s)  The participants performed 2 ankle self-stretching techniques (static stretching and SSS) for 3 weeks. Active DFROM (ADFROM), passive DFROM (PDFROM), and the lunge angle were measured. An independent t test was used to compare the improvements in these values before and after the 2 stretching interventions. The level of statistical significance was set at α = .05. Results  Active DFROM and PDFROM were greater in both stretching groups after the 3-week interventions. However, ADFROM, PDFROM, and the lunge angle were greater in the SSS group than in the static-stretching group (P < .05). Conclusions  Ankle SSS is recommended to improve ADFROM, PDFROM, and the lunge angle in individuals with limited DFROM. PMID:26633750

Comparison of custom-moulded ankle orthosis with hinged joints and off-the-shelf ankle braces in preventing ankle sprain in lateral cutting movements.

PubMed

Lee, Winson C C; Kobayashi, Toshiki; Choy, Barton T S; Leung, Aaron K L

2012-06-01

A custom moulded ankle orthosis with hinged joints potentially offers a better control over the subtalar joint and the ankle joint during lateral cutting movements, due to total contact design and increase in material strength. To test the above hypothesis by comparing it to three other available orthoses. Repeated measures. Eight subjects with a history of ankle sprains (Grade 2), and 11 subjects without such history performed lateral cutting movements in four test conditions: 1) non-orthotic, 2) custom-moulded ankle orthosis with hinges, 3) Sport-Stirrup, and 4) elastic ankle sleeve with plastic support. A VICON motion analysis system was used to study the motions at the ankle and subtalar joints. The custom-moulded ankle orthosis significantly lowered the inversion angle at initial contact (p = 0.006) and the peak inversion angle (p = 0.000) during lateral cutting movements in comparison to non-orthotic condition, while the other two orthoses did not. The three orthoses did not affect the plantarflexion motions, which had been suggested by previous studies to be important in shock wave attenuation. The custom-moulded ankle orthosis with hinges could better control inversion and thus expected to better prevent ankle sprain in lateral cutting movements. Custom-moulded ankle orthoses are not commonly used in preventing ankle sprains. This study raises the awareness of the use of custom-moulded ankle orthoses which are expected to better prevent ankle sprains.

A novel robot for imposing perturbations during overground walking: mechanism, control and normative stepping responses.

PubMed

Olenšek, Andrej; Zadravec, Matjaž; Matjačić, Zlatko

2016-06-11

, perturbations in sagittal plane are to greater extent handled by "ankle strategy" while angular perturbations in transversal plane do not pose substantial challenge for balance. Results also show that specific perturbation in general elicits responses that extend also to other planes of movement that are not directly associated with plane of perturbation as well as to spatio temporal parameters of gait.

Eversion Strength and Surface Electromyography Measures With and Without Chronic Ankle Instability Measured in 2 Positions.

PubMed

Donnelly, Lindsy; Donovan, Luke; Hart, Joseph M; Hertel, Jay

2017-07-01

Individuals with chronic ankle instability (CAI) have demonstrated strength deficits compared to healthy controls; however, the influence of ankle position on force measures and surface electromyography (sEMG) activation of the peroneus longus and brevis has not been investigated. The purpose of this study was to compare sEMG amplitudes of the peroneus longus and brevis and eversion force measures in 2 testing positions, neutral and plantarflexion, in groups with and without CAI. Twenty-eight adults (19 females, 9 males) with CAI and 28 healthy controls (19 females, 9 males) participated. Hand-held dynamometer force measures were assessed during isometric eversion contractions in 2 testing positions (neutral, plantarflexion) while surface sEMG amplitudes of the peroneal muscles were recorded. Force measures were normalized to body mass, and sEMG amplitudes were normalized to a resting period. The group with CAI demonstrated less force when compared to the control group ( P < .001) in both the neutral and plantarflexion positions: neutral position, CAI: 1.64 Nm/kg and control: 2.10 Nm/kg) and plantarflexion position, CAI: 1.40 Nm/kg and control: 1.73 Nm/kg). There were no differences in sEMG amplitudes between the groups or muscles ( P > .05). Force measures correlated with both muscles' sEMG amplitudes in the healthy group (neutral peroneus longus: r = 0.42, P = .03; plantarflexion peroneus longus: r = 0.56, P = .002; neutral peroneus brevis: r = 0.38, P = .05; plantarflexion peroneus longus: r = 0.40, P = .04), but not in the group with CAI ( P > .05). The group with CAI generated less force when compared to the control group during both testing positions. There was no selective activation of the peroneal muscles with testing in both positions, and force output and sEMG activity was only related in the healthy group. Clinicians should assess eversion strength and implement strength training exercises in different sagittal plane positions and evaluate for other

Self-Inflicted Drywall Screws in the Sagittal Sinus.

PubMed

Guppy, Kern H; Ochi, Calvin

2018-02-01

A 30-year-old right-handed man with a history of schizophrenia presented with 2 self-inflicted drywall screws in the skull. The patient was sleepy but easily arousable; blood tests showed he had taken methamphetamines. Computed tomography and computed tomography angiography of the head showed the frontal screw abutted left of the superior sagittal sinus, and the posterior screw went through the superior sagittal sinus with no extravasation of contrast material at either site. Both screws were removed with exposure of the sagittal sinus using U-shaped craniectomies. There was no bleeding on the removal of the screws. It appears the posterior screw entered between the leaflets of the sagittal sinus dura mater. The patient had returned to work without any sequelae 1 month after injury. Copyright © 2017 Elsevier Inc. All rights reserved.

Intermittent control with ankle, hip, and mixed strategies during quiet standing: a theoretical proposal based on a double inverted pendulum model.

PubMed

Suzuki, Yasuyuki; Nomura, Taishin; Casadio, Maura; Morasso, Pietro

2012-10-07

Human upright posture, as a mechanical system, is characterized by an instability of saddle type, involving both stable and unstable dynamic modes. The brain stabilizes such system by generating active joint torques, according to a time-delayed neural feedback control. What is still unsolved is a clear understanding of the control strategies and the control mechanisms that are used by the central nervous system in order to stabilize the unstable posture in a robust way while maintaining flexibility. Most studies in this direction have been limited to the single inverted pendulum model, which is useful for formalizing fundamental mechanical aspects but insufficient for addressing more general issues concerning neural control strategies. Here we consider a double inverted pendulum model in the sagittal plane with small passive viscoelasticity at the ankle and hip joints. Despite difficulties in stabilizing the double pendulum model in the presence of the large feedback delay, we show that robust and flexible stabilization of the upright posture can be established by an intermittent control mechanism that achieves the goal of stabilizing the body posture according to a "divide and conquer strategy", which switches among different controllers in different parts of the state space of the double inverted pendulum. Remarkably, it is shown that a global, robust stability is achieved even if the individual controllers are unstable and the information exploited for switching from one controller to another is severely delayed, as it happens in biological reality. Moreover, the intermittent controller can automatically resolve coordination among multiple active torques associated with the muscle synergy, leading to the emergence of distinct temporally coordinated active torque patterns, referred to as the intermittent ankle, hip, and mixed strategies during quiet standing, depending on the passive elasticity at the hip joint. Copyright © 2012 Elsevier Ltd. All rights reserved.

Primary ankle arthrodesis for neglected open Weber B ankle fracture dislocation.

PubMed

Thomason, Katherine; Ramesh, Ashwanth; McGoldrick, Niall; Cove, Richard; Walsh, James C; Stephens, Michael M

2014-01-01

Primary ankle arthrodesis used to treat a neglected open ankle fracture dislocation is a unique decision. A 63-year-old man presented to the emergency department with a 5-day-old open fracture dislocation of his right ankle. After thorough soft tissue debridement, primary arthrodesis of the tibiotalar joint was performed using initial Kirschner wire fixation and an external fixator. Definitive soft tissue coverage was later achieved using a latissimus dorsi free flap. The fusion was consolidated to salvage the limb from amputation. The use of primary arthrodesis to treat a compound ankle fracture dislocation has not been previously described. Copyright © 2014 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Treatment of common deficits associated with chronic ankle instability.

PubMed

Holmes, Alison; Delahunt, Eamonn

2009-01-01

Lateral ankle sprains are amongst the most common injuries incurred by athletes, with the high rate of reoccurrence after initial injury becoming of great concern. Chronic ankle instability (CAI) refers to the development of repetitive ankle sprains and persistent residual symptoms post-injury. Some of the initial symptoms that occur in acute sprains may persist for at least 6 months post-injury in the absence of recurrent sprains, despite the athlete having returned to full functional activity. CAI is generally thought to be caused by mechanical instability (MI) or functional instability (FI), or both. Although previously discussed as separate entities, recent research has demonstrated that deficits associated with both MI and FI may co-exist to result in CAI. For clinicians, the main deficits associated with CAI include deficits in proprioception, neuromuscular control, strength and postural control. Based on the literature reviewed, it does seem that subjects with CAI have a deficit in frontal plane ankle joint positional sense. Subjects with CAI do not appear to exhibit any increased latency in the peroneal muscles in response to an external perturbation. Preliminary data suggest that feed-forward neuromuscular control may be more important than feed-back neuromuscular control and interventions are now required to address deficits in feed-forward neuromuscular control. Balance training protocols have consistently been shown to improve postural stability in subjects with CAI. Subjects with CAI do not experience decreased peroneus longus strength, but instead may experience strength deficits in the ankle joint invertor muscles. These findings are of great clinical significance in terms of understanding the mechanisms and deficits associated with CAI. An appreciation of these is vital to allow clinicians to develop effective prevention and treatment programmes in relation to CAI.

The effect of directional inertias added to pelvis and ankle on gait

PubMed Central

2013-01-01

Background Gait training robots should display a minimum added inertia in order to allow normal walking. The effect of inertias in specific directions is yet unknown. We set up two experiments to assess the effect of inertia in anteroposterior (AP) direction to the ankle and AP and mediolateral (ML) direction to the pelvis. Methods We developed an experimental setup to apply inertia in forward backward and or sideways directions. In two experiments nine healthy subjects walked on a treadmill at 1.5 km/h and 4.5 km/h with no load and with AP loads of 0.3, 1.55 and 3.5 kg to the left ankle in the first experiment and combinations of AP and ML loads on the pelvis (AP loads 0.7, 4.3 and 10.2 kg; ML loads 0.6, 2.3 and 5.3 kg). We recorded metabolic rate, EMG of major leg muscles, gait parameters and kinematics. Results & discussion Adding 1.55 kg or more inertia to the ankle in AP direction increases the pelvis acceleration and decreases the foot acceleration in AP direction both at speeds of 4.5 km/h. Adding 3.5 kg of inertia to the ankle also increases the swing time as well as AP motions of the pelvis and head-arms-trunk (HAT) segment. Muscle activity remains largely unchanged. Adding 10.2 kg of inertia to the pelvis in AP direction causes a significant decrease of the pelvis and HAT segment motions, particularly at high speeds. Also the sagittal back flexion increases. Lower values of AP inertia and ML inertias up to 5.3 kg had negligible effect. In general the found effects are larger at high speeds. Conclusions We found that inertia up to 2 kg at the ankle or 6 kg added to the pelvis induced significant changes, but since these changes were all within the normal inter subject variability we considered these changes as negligible for application as rehabilitation robotics and assistive devices. PMID:23597391

Localizing Circuits of Atrial Macro-Reentry Using ECG Planes of Coherent Atrial Activation

PubMed Central

Kahn, Andrew M.; Krummen, David E.; Feld, Gregory K.; Narayan, Sanjiv M.

2007-01-01

Background The complexity of ablation for atrial macro-reentry (AFL) varies significantly depending upon the circuit location. Presently, surface ECG analysis poorly separates left from right atypical AFL and from some cases of typical AFL, delaying diagnosis until invasive study. Objective To differentiate and localize the intra-atrial circuits of left atypical AFL, right atypical, and typical AFL using quantitative ECG analysis. Methods We studied 66 patients (54 M, age 59±14 years) with typical (n=35), reverse typical (n=4) and atypical (n=27) AFL. For each, we generated filtered atrial waveforms from ECG leads V5 (X-axis), aVF (Y) and V1 (Z) by correlating a 120 ms F-wave sample to successive ECG regions. Atrial spatial loops were plotted for 3 orthogonal planes (frontal, XY=V5/aVF; sagittal, YZ=aVF/V1; axial, XZ=V5/V1), then cross-correlated to measure spatial regularity (‘coherence’: range −1 to 1). Results Mean coherence was greatest in the XY plane (p<10−3 vs XZ or YZ). Atypical AFL showed lower coherence than typical AFL in XY (p<10−3), YZ (p<10−6) and XZ (p<10−5) planes. Atypical left AFL could be separated from atypical right AFL by lower XY coherence (p=0.02); for this plane coherence < 0.69 detected atypical left AFL with 84% specificity and 75% sensitivity. F-wave amplitude did not separate typical, atypical right or atypical left AFL (p=NS). Conclusions Atypical AFL shows lower spatial coherence than typical AFL, particularly in sagittal and axial planes. Coherence in the Cartesian frontal plane separated left and right atypical AFL. Such analyses may be used to plan ablation strategy from the bedside. PMID:17399632

How can push-off be preserved during use of an ankle foot orthosis in children with hemiplegia? A prospective controlled study.

PubMed

Desloovere, Kaat; Molenaers, Guy; Van Gestel, Leen; Huenaerts, Catherine; Van Campenhout, Anja; Callewaert, Barbara; Van de Walle, Patricia; Seyler, J

2006-10-01

Several studies indicated that walking with an ankle foot orthosis (AFO) impaired third rocker. The purpose of this study was to evaluate the effects of two types of orthoses, with similar goal settings, on gait, in a homogeneous group of children, using both barefoot and shoe walking as control conditions. Fifteen children with hemiplegia, aged between 4 and 10 years, received two types of individually tuned AFOs: common posterior leaf-spring (PLS) and Dual Carbon Fiber Spring AFO (CFO) (with carbon fibre at the dorsal part of the orthosis). Both orthoses were expected to prevent plantar flexion, thus improving first rocker, allowing dorsiflexion to improve second rocker, absorbing energy during second rocker, and returning it during the third rocker. The effect of the AFOs was studied using objective gait analysis, including 3D kinematics, and kinetics in four conditions: barefoot, shoes without AFO, and PLS and CFO combined with shoes. Several gait parameters significantly changed in shoe walking compared to barefoot walking (cadence, ankle ROM and velocity, knee shock absorption, and knee angle in swing). The CFO produced a significantly larger ankle ROM and ankle velocity during push-off, and an increased plantar flexion moment and power generation at pre-swing compared to the PLS (<0.01). The results of this study further support the findings of previous studies indicating that orthoses improve specific gait parameters compared to barefoot walking (velocity, step length, first and second ankle rocker, sagittal knee and hip ROM). However, compared to shoes, not all improvements were statistically significant.

Effects of the application of ankle functional rehabilitation exercise on the ankle joint functional movement screen and isokinetic muscular function in patients with chronic ankle sprain.

PubMed

Ju, Sung-Bum; Park, Gi Duck

2017-02-01

[Purpose] This study was conducted to investigate the effects of ankle functional rehabilitation exercise on ankle joint functional movement screen results and isokinetic muscular function in patients with chronic ankle sprain patients. [Subjects and Methods] In this study, 16 patients with chronic ankle sprain were randomized to an ankle functional rehabilitation exercise group (n=8) and a control group (n=8). The ankle functional rehabilitation exercise centered on a proprioceptive sense exercise program, which was applied 12 times for 2 weeks. To verify changes after the application, ankle joint functional movement screen scores and isokinetic muscular function were measured and analyzed. [Results] The ankle functional rehabilitation exercise group showed significant improvements in all items of the ankle joint functional movement screen and in isokinetic muscular function after the exercise, whereas the control group showed no difference after the application. [Conclusion] The ankle functional rehabilitation exercise program can be effectively applied in patients with chronic ankle sprain for the improvement of ankle joint functional movement screen score and isokinetic muscular function.

Effects of the application of ankle functional rehabilitation exercise on the ankle joint functional movement screen and isokinetic muscular function in patients with chronic ankle sprain

PubMed Central

Ju, Sung-Bum; Park, Gi Duck

2017-01-01

[Purpose] This study was conducted to investigate the effects of ankle functional rehabilitation exercise on ankle joint functional movement screen results and isokinetic muscular function in patients with chronic ankle sprain patients. [Subjects and Methods] In this study, 16 patients with chronic ankle sprain were randomized to an ankle functional rehabilitation exercise group (n=8) and a control group (n=8). The ankle functional rehabilitation exercise centered on a proprioceptive sense exercise program, which was applied 12 times for 2 weeks. To verify changes after the application, ankle joint functional movement screen scores and isokinetic muscular function were measured and analyzed. [Results] The ankle functional rehabilitation exercise group showed significant improvements in all items of the ankle joint functional movement screen and in isokinetic muscular function after the exercise, whereas the control group showed no difference after the application. [Conclusion] The ankle functional rehabilitation exercise program can be effectively applied in patients with chronic ankle sprain for the improvement of ankle joint functional movement screen score and isokinetic muscular function. PMID:28265157

Ankle taping can reduce external ankle joint moments during drop landings on a tilted surface.

PubMed

Sato, Nahoko; Nunome, Hiroyuki; Hopper, Luke S; Ikegami, Yasuo

2017-09-20

Ankle taping is commonly used to prevent ankle sprains. However, kinematic assessments investigating the biomechanical effects of ankle taping have provided inconclusive results. This study aimed to determine the effect of ankle taping on the external ankle joint moments during a drop landing on a tilted surface at 25°. Twenty-five participants performed landings on a tilted force platform that caused ankle inversion with and without ankle taping. Landing kinematics were captured using a motion capture system. External ankle inversion moment, the angular impulse due to the medio-lateral and vertical components of ground reaction force (GRF) and their moment arm lengths about the ankle joint were analysed. The foot plantar inclination relative to the ground was assessed. In the taping condition, the foot plantar inclination and ankle inversion angular impulse were reduced significantly compared to that of the control. The only component of the external inversion moment to change significantly in the taped condition was a shortened medio-lateral GRF moment arm length. It can be assumed that the ankle taping altered the foot plantar inclination relative to the ground, thereby shortening the moment arm of medio-lateral GRF that resulted in the reduced ankle inversion angular impulse.

Shoulder motor performance assessment in the sagittal plane in children with hemiplegia during single joint pointing tasks.

PubMed

Formica, Domenico; Petrarca, Maurizio; Rossi, Stefano; Zollo, Loredana; Guglielmelli, Eugenio; Cappa, Paolo

2014-07-29

Pointing is a motor task extensively used during daily life activities and it requires complex visuo-motor transformation to select the appropriate movement strategy. The study of invariant characteristics of human movements has led to several theories on how the brain solves the redundancy problem, but the application of these theories on children affected by hemiplegia is limited. This study aims at giving a quantitative assessment of the shoulder motor behaviour in children with hemiplegia during pointing tasks. Eight children with hemiplegia were involved in the study and were asked to perform movements on the sagittal plane with both arms, at low and high speed. Subject movements were recorded using an optoelectronic system; a 4-DOF model of children arm has been developed to calculate kinematic and dynamic variables. A set of evaluation indexes has been extracted in order to quantitatively assess whether and how children modify their motor control strategies when perform movements with the more affected or less affected arm. In low speed movements, no differences can be seen in terms of movement duration and peak velocity between the More Affected arm (MA) and the Less Affected arm (LA), as well as in the main characteristics of movement kinematics and dynamics. As regards fast movements, remarkable differences in terms of strategies of motor control can be observed: while movements with LA did not show any significant difference in Dimensionless Jerk Index (JI) and Dimensionless Torque-change Cost index (TC) between the elevation and lowering phases, suggesting that motor control optimization is similar for movements performed with or against gravity, movements with MA showed a statistically significant increase of both JI and TC during lowering phase. Results suggest the presence of a different control strategy for fast movements in particular during lowering phase. Results suggest that motor control is not able to optimize Jerk and Torque-change cost

Reliability and accuracy of a goniometer mobile device application for video measurement of the functional movement screen deep squat test.

PubMed

Krause, David A; Boyd, Michael S; Hager, Allison N; Smoyer, Eric C; Thompson, Anthony T; Hollman, John H

2015-02-01

The squat is a fundamental movement of many athletic and daily activities. Methods to clinically assess the squat maneuver range from simple observation to the use of sophisticated equipment. The purpose of this study was to examine the reliability of Coach's Eye (TechSmith Corp), a 2-dimensional (2D) motion analysis mobile device application (app), for assessing maximal sagittal plane hip, knee, and ankle motion during a functional movement screen deep squat, and to compare range of motion values generated by it to those from a Vicon (Vicon Motion Systems Ltd) 3-dimensional (3D) motion analysis system. Twenty-six healthy subjects performed three functional movement screen deep squats recorded simultaneously by both the app (on an iPad [Apple Inc]) and the 3D motion analysis system. Joint angle data were calculated with Vicon Nexus software (Vicon Motion Systems Ltd). The app video was analyzed frame by frame to determine, and freeze on the screen, the deepest position of the squat. With a capacitive stylus reference lines were then drawn on the iPad screen to determine joint angles. Procedures were repeated with approximately 48 hours between sessions. Test-retest intrarater reliability (ICC3,1) for the app at the hip, knee, and ankle was 0.98, 0.98, and 0.79, respectively. Minimum detectable change was hip 6°, knee 6°, and ankle 7°. Hip joint angles measured with the 2D app exceeded measurements obtained with the 3D motion analysis system by approximately 40°. Differences at the knee and ankle were of lower magnitude, with mean differences of 5° and 3°, respectively. Bland-Altman analysis demonstrated a systematic bias in the hip range-of-motion measurement. No such bias was demonstrated at the knee or ankle. The 2D app demonstrated excellent reliability and appeared to be a responsive means to assess for clinical change, with minimum detectable change values ranging from 6° to 7°. These results also suggest that the 2D app may be used as an alternative

Reliability and smallest real difference of the ankle lunge test post ankle fracture.

PubMed

Simondson, David; Brock, Kim; Cotton, Susan

2012-02-01

This study aimed to determine the reliability and the smallest real difference of the Ankle Lunge test in an ankle fracture patient population. In the post immobilisation stage of ankle fracture, ankle dorsiflexion is an important measure of progress and outcome. The Ankle Lunge test measures weight bearing dorsiflexion, resulting in negative scores (knee to wall distance) and positive scores (toe to wall distance), for which the latter has proven reliability in normal subjects only. A consecutive sample of ankle fracture patients with permission to commence weight bearing, were recruited to the study. Three measurements of the Ankle Lunge Test were performed each by two raters, one senior and one junior physiotherapist. These occurred prior to therapy sessions in the second week after plaster removal. A standardised testing station was utilised and allowed for both knee to wall distance and toe to wall distance measurement. Data was collected from 10 individuals with ankle fracture, with an average age of 36 years (SD 14.8). Seventy seven percent of observations were negative. Intra and inter-rater reliability yielded intra class correlations at or above 0.97, p < .001. There was a significant systematic bias towards improved scores during repeated measurement for one rater (p = .01). The smallest real difference was calculated as 13.8mm. The Ankle Lunge test is a practical and reliable tool for measuring weightbearing dorsiflexion post ankle fracture. Copyright © 2011 Elsevier Ltd. All rights reserved.

Whole-body angular momentum during stair walking using passive and powered lower-limb prostheses.

PubMed

Pickle, Nathaniel T; Wilken, Jason M; Aldridge, Jennifer M; Neptune, Richard R; Silverman, Anne K

2014-10-17

Individuals with a unilateral transtibial amputation have a greater risk of falling compared to able-bodied individuals, and falling on stairs can lead to serious injuries. Individuals with transtibial amputations have lost ankle plantarflexor muscle function, which is critical for regulating whole-body angular momentum to maintain dynamic balance. Recently, powered prostheses have been designed to provide active ankle power generation with the goal of restoring biological ankle function. However, the effects of using a powered prosthesis on the regulation of whole-body angular momentum are unknown. The purpose of this study was to use angular momentum to evaluate dynamic balance in individuals with a transtibial amputation using powered and passive prostheses relative to able-bodied individuals during stair ascent and descent. Ground reaction forces, external moment arms, and joint powers were also investigated to interpret the angular momentum results. A key result was that individuals with an amputation had a larger range of sagittal-plane angular momentum during prosthetic limb stance compared to able-bodied individuals during stair ascent. There were no significant differences in the frontal, transverse, or sagittal-plane ranges of angular momentum or maximum magnitude of the angular momentum vector between the passive and powered prostheses during stair ascent or descent. These results indicate that individuals with an amputation have altered angular momentum trajectories during stair walking compared to able-bodied individuals, which may contribute to an increased fall risk. The results also suggest that a powered prosthesis provides no distinct advantage over a passive prosthesis in maintaining dynamic balance during stair walking. Copyright © 2014 Elsevier Ltd. All rights reserved.

Therapeutic interventions for increasing ankle dorsiflexion after ankle sprain: a systematic review.

PubMed

Terada, Masafumi; Pietrosimone, Brian G; Gribble, Phillip A

2013-01-01

Clinicians perform therapeutic interventions, such as stretching, manual therapy, electrotherapy, ultrasound, and exercises, to increase ankle dorsiflexion. However, authors of previous studies have not determined which intervention or combination of interventions is most effective. To determine the magnitude of therapeutic intervention effects on and the most effective therapeutic interventions for restoring normal ankle dorsiflexion after ankle sprain. We performed a comprehensive literature search in Web of Science and EBSCO HOST from 1965 to May 29, 2011, with 19 search terms related to ankle sprain, dorsiflexion, and intervention and by cross-referencing pertinent articles. Eligible studies had to be written in English and include the means and standard deviations of both pretreatment and posttreatment in patients with acute, subacute, or chronic ankle sprains. Outcomes of interest included various joint mobilizations, stretching, local vibration, hyperbaric oxygen therapy, electrical stimulation, and mental-relaxation interventions. We extracted data on dorsiflexion improvements among various therapeutic applications by calculating Cohen d effect sizes with associated 95% confidence intervals (CIs) and evaluated the methodologic quality using the Physiotherapy Evidence Database (PEDro) scale. In total, 9 studies (PEDro score = 5.22 ± 1.92) met the inclusion criteria. Static-stretching interventions with a home exercise program had the strongest effects on increasing dorsiflexion in patients 2 weeks after acute ankle sprains (Cohen d = 1.06; 95% CI = 0.12, 2.42). The range of effect sizes for movement with mobilization on ankle dorsiflexion among individuals with recurrent ankle sprains was small (Cohen d range = 0.14 to 0.39). Static-stretching intervention as a part of standardized care yielded the strongest effects on dorsiflexion after acute ankle sprains. The existing evidence suggests that clinicians need to consider what may be the limiting factor of

The effect of combined mechanism ankle support on postural control of patients with chronic ankle instability.

PubMed

Hadadi, Mohammad; Ebrahimi, Ismaeil; Mousavi, Mohammad Ebrahim; Aminian, Gholamreza; Esteki, Ali; Rahgozar, Mehdi

2017-02-01

Chronic ankle instability is associated with neuromechanical changes and poor postural stability. Despite variety of mechanisms of foot and ankle orthoses, almost none apply comprehensive mechanisms to improve postural control in all subgroups of chronic ankle instability patients. The purpose of this study was to investigate the effect of an ankle support implementing combined mechanisms to improve postural control in chronic ankle instability patients. Cross-sectional study. An ankle support with combined mechanism was designed based on most effective action mechanisms of foot and ankle orthoses. The effect of this orthosis on postural control was evaluated in 20 participants with chronic ankle instability and 20 matched healthy participants. The single-limb stance balance test was measured in both groups with and without the new orthosis using a force platform. The results showed that application of combined mechanism ankle support significantly improved all postural sway parameters in chronic ankle instability patients. There were no differences in means of investigated parameters with and without the orthosis in the healthy group. No statistically significant differences were found in postural sway between chronic ankle instability patients and healthy participants after applying the combined mechanism ankle support. The combined mechanism ankle support is effective in improving static postural control of chronic ankle instability patients to close to the postural sway of healthy individual. the orthosis had no adverse effects on balance performance of healthy individuals. Clinical relevance Application of the combined mechanism ankle support for patients with chronic ankle instability is effective in improving static balance. This may be helpful in reduction of recurrence of ankle sprain although further research about dynamic conditions is needed.

Ankle fracture spur sign is pathognomonic for a variant ankle fracture.

PubMed

Hinds, Richard M; Garner, Matthew R; Lazaro, Lionel E; Warner, Stephen J; Loftus, Michael L; Birnbaum, Jacqueline F; Burket, Jayme C; Lorich, Dean G

2015-02-01

The hyperplantarflexion variant ankle fracture is composed of a posterior tibial lip fracture with posterolateral and posteromedial fracture fragments separated by a vertical fracture line. This infrequently reported injury pattern often includes an associated "spur sign" or double cortical density at the inferomedial tibial metaphysis. The objective of this study was to quantitatively establish the association of the ankle fracture spur sign with the hyperplantarflexion variant ankle fracture. Our clinical database of operative ankle fractures was retrospectively reviewed for the incidence of hyperplantarflexion variant and nonvariant ankle fractures as determined by assessment of injury radiographs, preoperative advanced imaging, and intraoperative observation. Injury radiographs were then evaluated for the presence of the spur sign, and association between the spur sign and variant fractures was analyzed. The incidence of the hyperplantarflexion variant fracture among all ankle fractures was 6.7% (43/640). The spur sign was present in 79% (34/43) of variant fractures and absent in all nonvariant fractures, conferring a specificity of 100% in identifying variant fractures. Positive predictive value and negative predictive value were 100% and 99%, respectively. The ankle fracture spur sign was pathognomonic for the hyperplantarflexion variant ankle fracture. It is important to identify variant fractures preoperatively as patient positioning, operative approach, and fixation construct of variant fractures often differ from those employed for osteosynthesis of nonvariant fractures. Identification of the spur sign should prompt acquisition of advanced imaging to formulate an appropriate operative plan to address the variant fracture pattern. Level III, retrospective comparative study. © The Author(s) 2014.

The leather ankle lacer.

PubMed Central

Saltzman, C. L.; Shurr, D.; Kamp, J.; Cook, T. A.

1995-01-01

The purpose of this study was to evaluate the efficacy of a leather ankle lacer for treating painful problems of the ankle and hindfoot. The evaluation involved patient self assessment, clinical examination and radiographic determination of the effectiveness of the ankle lacer. Overall, patients had moderate pain relief with significant but not complete restriction of motion. Based on this study and our clinical experience, we find the leather ankle lacer to be a compliant and comfortable treatment strategy for patients with painful ankle and hindfoot problems who desire some retained motion. Images Figure 1A & B Figure 2 Figure 3 PMID:7634034

Analysis of the Effects of Normal Walking on Ankle Joint Contact Characteristics After Acute Inversion Ankle Sprain.

PubMed

Bae, Ji Yong; Park, Kyung Soon; Seon, Jong Keun; Jeon, Insu

2015-12-01

To show the causal relationship between normal walking after various lateral ankle ligament (LAL) injuries caused by acute inversion ankle sprains and alterations in ankle joint contact characteristics, finite element simulations of normal walking were carried out using an intact ankle joint model and LAL injury models. A walking experiment using a volunteer with a normal ankle joint was performed to obtain the boundary conditions for the simulations and to support the appropriateness of the simulation results. Contact pressure and strain on the talus articular cartilage and anteroposterior and mediolateral translations of the talus were calculated. Ankles with ruptured anterior talofibular ligaments (ATFLs) had a higher likelihood of experiencing increased ankle joint contact pressures, strains and translations than ATFL-deficient ankles. In particular, ankles with ruptured ATFL + calcaneofibular ligaments and all ruptured ankles had a similar likelihood as the ATFL-ruptured ankles. The push off stance phase was the most likely situation for increased ankle joint contact pressures, strains and translations in LAL-injured ankles.

Development of a method for fabricating polypropylene non-articulated dorsiflexion assist ankle foot orthoses with predetermined stiffness.

PubMed

Ramsey, Jason Allan

2011-03-01

A non-articulated plantarflexion resist ankle foot orthosis (AFO), commonly known as a posterior leaf spring AFO, is indicated for patients with motor impairment to the dorsiflexors. The AFO is often custom molded to a patient's lower limb anatomy and fabricated from polypropylene. There are no established guidelines for fabricating this type of AFO with predetermined stiffness of the ankle region for normal walking speeds. Therefore an AFO may not meet the biomechanical needs of the patient. Quantify the biomechanical ankle stiffness requirement for an individual with complete dorsiflexor impairment and develop a method for fabricating an AFO with ankle stiffness to meet that requirement. Experimental, bench research. The literature on sagittal biomechanics of non-pathological adults was reviewed to derive the stiffness of the ankle during loading response. Computer models of 144 AFOs were created with geometric variations to account for differences in human anthropometrics. Computer-based finite element analysis was employed to determine the stiffness and safety factor of the models. Stiffness of the AFOs ranged from 0.04 to 1.8 Nm/deg. This ample range is expected to account for the stiffness required for most adults with complete dorsiflexor impairment. At 5° deflection the factor of safety (ratio of strength to stress) ranged from 2.8 to 9.1. A computer program was generated that computes AFO stiffness from user-input variables of AFO geometry. The stiffness is compared to a theoretically appropriate stiffness based on the patient mass. The geometric variables can be modified until there is a close match, resulting in AFO design specification that is appropriate for the patient. Through validation on human subjects, this method may benefit patient outcomes in clinical practice by avoiding the current uncertainty surrounding AFO performance and reducing the labor and time involved in rectifying a custom AFO post-fabrication. This method provides an avenue for

Effect of Trunk Sagittal Attitude on Shoulder, Thorax and Pelvis Three-Dimensional Kinematics in Able-Bodied Subjects during Gait

PubMed Central

Leardini, Alberto; Berti, Lisa; Begon, Mickaël; Allard, Paul

2013-01-01

It has been shown that an original attitude in forward or backward inclination of the trunk is maintained at gait initiation and during locomotion, and that this affects lower limb loading patterns. However, no studies have shown the extent to which shoulder, thorax and pelvis three-dimensional kinematics are modified during gait due to this sagittal inclination attitude. Thirty young healthy volunteers were analyzed during level walking with video-based motion analysis. Reflecting markers were mounted on anatomical landmarks to form a two-marker shoulder line segment, and a four-marker thorax and pelvis segments. Absolute and relative spatial rotations were calculated, for a total of 11 degrees of freedom. The subjects were divided into two groups of 15 according to the median of mean thorax inclination angle over the gait cycle. Preliminary MANOVA analysis assessed whether gender was an independent variable. Then two-factor nested ANOVA was used to test the possible effect of thorax inclination on body segments, planes of motion and gait periods, separately. There was no significant difference in all anthropometric and spatio-temporal parameters between the two groups, except for subject mass. The three-dimensional kinematics of the thorax and pelvis were not affected by gender. Nested ANOVA revealed group effect in all segment rotations apart those at the pelvis, in the sagittal and frontal planes, and at the push-off. Attitudes in sagittal thorax inclination altered trunk segments kinematics during gait. Subjects with a backward thorax showed less thorax-to-pelvis motion, but more shoulder-to-thorax and thorax-to-laboratory motion, less motion in flexion/extension and in lateral bending, and also less motion during push-off. This contributes to the understanding of forward propulsion and sideways load transfer mechanisms, fundamental for the maintenance of balance and the risk of falling. PMID:24204763

Effect of trunk sagittal attitude on shoulder, thorax and pelvis three-dimensional kinematics in able-bodied subjects during gait.

PubMed

Leardini, Alberto; Berti, Lisa; Begon, Mickaël; Allard, Paul

2013-01-01

It has been shown that an original attitude in forward or backward inclination of the trunk is maintained at gait initiation and during locomotion, and that this affects lower limb loading patterns. However, no studies have shown the extent to which shoulder, thorax and pelvis three-dimensional kinematics are modified during gait due to this sagittal inclination attitude. Thirty young healthy volunteers were analyzed during level walking with video-based motion analysis. Reflecting markers were mounted on anatomical landmarks to form a two-marker shoulder line segment, and a four-marker thorax and pelvis segments. Absolute and relative spatial rotations were calculated, for a total of 11 degrees of freedom. The subjects were divided into two groups of 15 according to the median of mean thorax inclination angle over the gait cycle. Preliminary MANOVA analysis assessed whether gender was an independent variable. Then two-factor nested ANOVA was used to test the possible effect of thorax inclination on body segments, planes of motion and gait periods, separately. There was no significant difference in all anthropometric and spatio-temporal parameters between the two groups, except for subject mass. The three-dimensional kinematics of the thorax and pelvis were not affected by gender. Nested ANOVA revealed group effect in all segment rotations apart those at the pelvis, in the sagittal and frontal planes, and at the push-off. Attitudes in sagittal thorax inclination altered trunk segments kinematics during gait. Subjects with a backward thorax showed less thorax-to-pelvis motion, but more shoulder-to-thorax and thorax-to-laboratory motion, less motion in flexion/extension and in lateral bending, and also less motion during push-off. This contributes to the understanding of forward propulsion and sideways load transfer mechanisms, fundamental for the maintenance of balance and the risk of falling.

Ankle and knee biomechanics during normal walking following ankle plantarflexor fatigue.

PubMed

Hunt, Michael A; Hatfield, Gillian L

2017-08-01

The purpose of this study was to investigate the immediate effects of unilateral ankle plantarflexor fatigue on bilateral knee and ankle biomechanics during gait. Lower leg kinematics, kinetics, and muscle activation were assessed before and after an ankle plantarflexor fatiguing protocol in 31 healthy individuals. Fatigue (defined as >10% reduction in maximal isometric ankle plantarflexor torque production and a downward shift in the median power frequency of both heads of the gastrocnemius muscle of the fatigued limb) was achieved in 18 individuals, and only their data were used for analysis purposes. Compared to pre-fatigue walking trials, medial gastrocnemius activity was significantly reduced in the study (fatigued) limb. Other main changes following fatigue included significantly more knee flexion during loading, and an associated larger external knee flexion moment in the study limb. At the ankle joint, participants exhibited significantly less peak plantarflexion (occurring at toe-off) with fatigue. No significant differences were observed in the contralateral (non-fatigued) limb. Findings from this study indicate that fatigue of the ankle plantarflexor muscle does not produce widespread changes in gait biomechanics, suggesting that small to moderate changes in maximal ankle plantarflexor force production capacity (either an increase or decrease) will not have a substantial impact on normal lower limb functioning during gait. Copyright © 2017 Elsevier Ltd. All rights reserved.

Acute proximal junctional failure in patients with preoperative sagittal imbalance.

PubMed

Smith, Micah W; Annis, Prokopis; Lawrence, Brandon D; Daubs, Michael D; Brodke, Darrel S

2015-10-01

Proximal junctional failure (PJF) is a recognized complication of spinal deformity surgery. Acute PJF (APJF) has recently been demonstrated to be 5.6% in the adult spinal deformity (ASD) population. The incidence and rate of return to the operating room for APJF have not been specifically investigated in individuals with sagittal imbalance. The purpose of this study was to report the incidence of APJF in patients with preoperative sagittal imbalance and the rate of return to the operating room for APJF. This study is based on a retrospective review of prospectively collected database of ASD patients. One hundred seventy-three consecutive patients were included with preoperative sagittal imbalance according to one of the following common parameters: sagittal vertical axis (SVA) greater than 50 mm, global sagittal alignment greater than 45°, or pelvic incidence minus lumbar lordosis greater than 10°. Outcome measure was presence and/or absence of APJF defined as fracture at the upper instrumented vertebra (UIV) or UIV+1, failure of UIV fixation, 15° or more proximal junctional kyphosis, or need for extension of instrumentation within 6 months of surgery. We performed radiographic measurements on X-rays at preoperative, immediate postoperative, and 6-month follow-up visits. The APJF rate was reported for the entire patient population with preoperative sagittal imbalance. Acute PJF incidence was calculated postoperatively for each of the accepted sagittal balance parameters and/or formulas. Patients with persistent postoperative sagittal imbalance were compared with the sagittally balanced group. We also assessed for threshold values. Acute PJF was observed in 60 of 173 patients (35%) and was least common in fusions with the UIV in the upper thoracic (UT) spine (p=.035). Of those who developed APJF, 21.7% required surgery. Proximal junctional kyphosis 15° or more was the most common form of APJF in fusions to the UT spine but least likely to need revision (p=.014

Sagittal Balance in Adolescent Idiopathic Scoliosis

PubMed Central

Xu, Xi-Ming; Wang, Fei; Zhou, Xiao-Yi; Liu, Zi-Xuan; Wei, Xian-Zhao; Bai, Yu-Shu; Li, Ming

2015-01-01

Abstract The relationship between spinal sagittal alignment and pelvic parameters is well known in adolescent idiopathic scoliosis. However, few studies have reported the sagittal spinopelvic relationship after selective posterior fusion of thoracolumbar/lumbar (TL/L) curves. We evaluated the relationship between spinal sagittal alignment and the pelvis, and analyzed how the pelvic sagittal state is adjusted in Lenke type 5C patients. We conducted a retrospective study of 36 patients with Lenke type 5C curves who received selective posterior TL/L curve fusion. Coronal and spinopelvic sagittal parameters were pre and postoperatively compared. Pearson coefficients were used to analyze the correlation between all spinopelvic sagittal parameters before and after surgery. We also evaluated 3 pelvic morphologies (anteverted, normal, and retroverted) before and after surgery. Preoperatively, the mean pelvic incidence was 46.0°, with a pelvic tilt and sacral slope (SS) of 8.2° and 37.8°, respectively, and 25% (9/36) of patients had an anteverted pelvis, whereas the other 75% had a normal pelvis. Postoperatively, 42% (15/36) of patients had a retroverted pelvis, 53% (19/36) had a normal pelvis, and 2 patients had an anteverted pelvis. Logistic regression analyses yielded 2 factors that were significantly associated with the risk for a postoperative unrecovered anteverted pelvis, including increased lumbar lordosis (LL) (odds ratio [OR] 4.8, P = 0.029) and increased SS (OR 5.6, P = 0.018). Four factors were significantly associated with the risk of a postoperative newly anteverted pelvis, including LL at the final follow-up (OR 6.9, P = 0.009), increased LL (OR 8.9, P = 0.003), LL below fusion (OR 9.4, P = 0.002), and increased SS (OR 11.5, P = 0.001). The pelvic state may be adjusted after selective posterior TL/L curve fusion in Lenke 5C adolescent idiopathic scoliosis patients. It is difficult to improve an anteverted pelvis in patients who have

Mechanical instability destabilises the ankle joint directly in the ankle-sprain mechanism.

PubMed

Gehring, Dominic; Faschian, Katrin; Lauber, Benedikt; Lohrer, Heinz; Nauck, Tanja; Gollhofer, Albert

2014-03-01

Despite massive research efforts, it remains unclear how mechanical ankle instability (MAI) and functional ankle instability (FAI) affect joint control in the situation of ankle sprain. Thus, the purpose of this study was to evaluate whether individuals with MAI have deficits in stabilising their ankle joint in a close-to-injury situation compared with those with FAI and healthy controls. Ankle-joint control was assessed by means of three-dimensional motion analysis and electromyography in participants with FAI and MAI (n=19), in participants with pure FAI (n=9) and in healthy controls (n=18). Close-to-injury situations were simulated during standing, walking and jumping by means of a custom-made tilt platform. Individuals with FAI and MAI displayed significantly greater maximum ankle inversion angles (+5°) and inversion velocities (+50°/s) in the walking and jumping conditions compared to those with pure FAI and controls. Furthermore, individuals in the FAI and MAI group showed a significantly decreased pre-activation of the peroneus longus muscle during jumping compared to those with FAI. No differences between groups were found for plantar flexion and internal rotation, or for muscle activities following tilting of the platform. The present study demonstrates that MAI is characterised by impairments of ankle-joint control in close-to-injury situations. This could make these individuals more prone to recurrent ankle sprains, and suggests the need for additional mechanical support such as braces or even surgery. In addition, the study highlights the fact that dynamic experimental test conditions in the acting participant are needed to further unravel the mystery of chronic ankle instability.

Comprehensive Analysis of Mandibular Residual Asymmetry after Bilateral Sagittal Split Ramus Osteotomy Correction of Menton Point Deviation

PubMed Central

Lin, Qiuping; Huang, Xiaoqiong; Xu, Yue; Yang, Xiaoping

2016-01-01

Purpose Facial asymmetry often persists even after mandibular deviation corrected by the bilateral sagittal split ramus osteotomy (BSSRO) operation, since the reference facial sagittal plane for the asymmetry analysis is usually set up before the mandibular menton (Me) point correction. Our aim is to develop a predictive and quantitative method to assess the true asymmetry of the mandible after a midline correction performed by a virtual BSSRO, and to verify its availability by evaluation of the post-surgical improvement. Patients and Methods A retrospective cohort study was conducted at the Hospital of Stomatology, Sun Yat-sen University (China) of patients with pure hemi-mandibular elongation (HE) from September 2010 through May 2014. Mandibular models were reconstructed from CBCT images of patients with pre-surgical orthodontic treatment. After mandibular de-rotation and midline alignment with virtual BSSRO, the elongation hemi-mandible was virtually mirrored along the facial sagittal plane. The residual asymmetry, defined as the superimposition and boolean operation of the mirrored elongation side on the normal side, was calculated, including the volumetric differences and the length of transversal and vertical asymmetry discrepancy. For more specific evaluation, both sides of the hemi-mandible were divided into the symphysis and parasymphysis (SP), mandibular body (MB), and mandibular angle (MA) regions. Other clinical variables include deviation of Me point, dental midline and molar relationship. The measurement of volumetric discrepancy between the two sides of post-surgical hemi-mandible were also calculated to verify the availability of virtual surgery. Paired t-tests were computed and the P value was set at .05. Results This study included 45 patients. The volume differences were 407.8±64.8 mm3, 2139.1±72.5 mm3, and 422.5±36.9 mm3; residual average transversal discrepancy, 1.9 mm, 1.0 mm, and 2.2 mm; average vertical discrepancy, 1.1 mm, 2.2 mm, and 2

Comprehensive Analysis of Mandibular Residual Asymmetry after Bilateral Sagittal Split Ramus Osteotomy Correction of Menton Point Deviation.

PubMed

Lin, Han; Zhu, Ping; Lin, Qiuping; Huang, Xiaoqiong; Xu, Yue; Yang, Xiaoping

2016-01-01

Facial asymmetry often persists even after mandibular deviation corrected by the bilateral sagittal split ramus osteotomy (BSSRO) operation, since the reference facial sagittal plane for the asymmetry analysis is usually set up before the mandibular menton (Me) point correction. Our aim is to develop a predictive and quantitative method to assess the true asymmetry of the mandible after a midline correction performed by a virtual BSSRO, and to verify its availability by evaluation of the post-surgical improvement. A retrospective cohort study was conducted at the Hospital of Stomatology, Sun Yat-sen University (China) of patients with pure hemi-mandibular elongation (HE) from September 2010 through May 2014. Mandibular models were reconstructed from CBCT images of patients with pre-surgical orthodontic treatment. After mandibular de-rotation and midline alignment with virtual BSSRO, the elongation hemi-mandible was virtually mirrored along the facial sagittal plane. The residual asymmetry, defined as the superimposition and boolean operation of the mirrored elongation side on the normal side, was calculated, including the volumetric differences and the length of transversal and vertical asymmetry discrepancy. For more specific evaluation, both sides of the hemi-mandible were divided into the symphysis and parasymphysis (SP), mandibular body (MB), and mandibular angle (MA) regions. Other clinical variables include deviation of Me point, dental midline and molar relationship. The measurement of volumetric discrepancy between the two sides of post-surgical hemi-mandible were also calculated to verify the availability of virtual surgery. Paired t-tests were computed and the P value was set at .05. This study included 45 patients. The volume differences were 407.8±64.8 mm3, 2139.1±72.5 mm3, and 422.5±36.9 mm3; residual average transversal discrepancy, 1.9 mm, 1.0 mm, and 2.2 mm; average vertical discrepancy, 1.1 mm, 2.2 mm, and 2.2 mm (before virtual surgery). The

Ankle syndesmotic injury.

PubMed

Zalavras, Charalampos; Thordarson, David

2007-06-01

Ankle syndesmotic injury does not necessarily lead to ankle instability; however, the coexistence of deltoid ligament injury critically destabilizes the ankle joint. Syndesmotic injury may occur in isolation or may be associated with ankle fracture. In the absence of fracture, physical examination findings suggestive of injury include ankle tenderness over the anterior aspect of the syndesmosis and a positive squeeze or external rotation test. Radiographic findings usually include increased tibiofibular clear space decreased tibiofibular overlap, and increased medial clear space. However, syndesmotic injury may not be apparent radiographically; thus, routine stress testing is necessary for detecting syndesmotic instability. The goals of management are to restore and maintain the normal tibiofibular relationship to allow for healing of the ligamentous structures of the syndesmosis. Fixation of the syndesmosis is indicated when evidence of a diastasis is present. This may be detected preoperatively, in the absence of fracture, or intraoperatively, after rigid fixation of the medial malleolus and fibula fractures. Failure to diagnose and stabilize syndesmotic disruption adversely affects outcome.

Therapeutic Interventions for Increasing Ankle Dorsiflexion After Ankle Sprain: A Systematic Review

PubMed Central

Terada, Masafumi; Pietrosimone, Brian G.; Gribble, Phillip A.

2013-01-01

Context: Clinicians perform therapeutic interventions, such as stretching, manual therapy, electrotherapy, ultrasound, and exercises, to increase ankle dorsiflexion. However, authors of previous studies have not determined which intervention or combination of interventions is most effective. Objective: To determine the magnitude of therapeutic intervention effects on and the most effective therapeutic interventions for restoring normal ankle dorsiflexion after ankle sprain. Data Sources: We performed a comprehensive literature search in Web of Science and EBSCO HOST from 1965 to May 29, 2011, with 19 search terms related to ankle sprain, dorsiflexion, and intervention and by cross-referencing pertinent articles. Study Selection: Eligible studies had to be written in English and include the means and standard deviations of both pretreatment and posttreatment in patients with acute, subacute, or chronic ankle sprains. Outcomes of interest included various joint mobilizations, stretching, local vibration, hyperbaric oxygen therapy, electrical stimulation, and mental-relaxation interventions. Data Extraction: We extracted data on dorsiflexion improvements among various therapeutic applications by calculating Cohen d effect sizes with associated 95% confidence intervals (CIs) and evaluated the methodologic quality using the Physiotherapy Evidence Database (PEDro) scale. Data Synthesis: In total, 9 studies (PEDro score = 5.22 ± 1.92) met the inclusion criteria. Static-stretching interventions with a home exercise program had the strongest effects on increasing dorsiflexion in patients 2 weeks after acute ankle sprains (Cohen d = 1.06; 95% CI = 0.12, 2.42). The range of effect sizes for movement with mobilization on ankle dorsiflexion among individuals with recurrent ankle sprains was small (Cohen d range = 0.14 to 0.39). Conclusions: Static-stretching intervention as a part of standardized care yielded the strongest effects on dorsiflexion after acute ankle sprains. The

Development of a sliding mode control model for quiet upright stance.

PubMed

Zhang, Hongbo; Nussbaum, Maury A; Agnew, Michael J

2016-02-01

Human upright stance appears maintained or controlled intermittently, through some combination of passive and active ankle torques, respectively representing intrinsic and contractile contributions of the ankle musculature. Several intermittent postural control models have been proposed, though it has been challenging to accurately represent actual kinematics and kinetics and to separately estimate passive and active ankle torque components. Here, a simplified single-segment, 2D (sagittal plane) sliding mode control model was developed for application to track kinematics and kinetics during upright stance. The model was implemented and evaluated using previous experimental data consisting of whole body angular kinematics and ankle torques. Tracking errors for the whole-body center-of-mass (COM) angle and angular velocity, as well as ankle torque, were all within ∼10% of experimental values, though tracking performance for COM angular acceleration was substantially poorer. The model also enabled separate estimates of the contributions of passive and active ankle torques, with overall contributions estimated here to be 96% and 4% of the total ankle torque, respectively. Such a model may have future utility in understanding human postural control, though additional work is needed, such as expanding the model to multiple segments and to three dimensions. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

Sprained Ankles

MedlinePlus

... away before the ligament is injured. Types of Sprains In young children, the ankle is the most commonly sprained joint, followed by ... A walking cast may be necessary if the ankle or foot injury has been severe. Most grade 1 sprains will heal within two weeks without subsequent complications. ...

Biomechanical effects of body weight support with a novel robotic walker for over-ground gait rehabilitation.

PubMed

Mun, Kyung-Ryoul; Lim, Su Bin; Guo, Zhao; Yu, Haoyong

2017-02-01

Body weight support (BWS) promotes better functional outcomes for neurologically challenged patients. Despite the established effectiveness of BWS in gait rehabilitation, the findings on biomechanical effects of BWS training still remain contradictory. Therefore, the aim of this study is to comprehensively investigate the effects of BWS. Using a newly developed robotic walker which can facilitate pelvic motions with an active BWS unit, we compared gait parameters of ten healthy subjects during a 10-m walk with incremental levels of body weight unloading, ranging from 0 to 40 % at 10 % intervals. Significant changes in joint angles and gait temporospatial parameters were observed. In addition, the results of an EMG signal study showed that the intensity of muscle activation was significantly reduced with increasing BWS levels. The reduction was found at the ankle, knee, and hip joints in the sagittal plane as well as at the hip joint in the frontal plane. The results of this study provide an important indication of increased lateral body balance and greater stabilization in sagittal and frontal plane during gait. Our findings provide a better understanding of the biomechanical effects of BWS during gait, which will help guide the gait rehabilitation strategies.

Test-retest reliability of sudden ankle inversion measurements in subjects with healthy ankle joints.

PubMed

Eechaute, Christophe; Vaes, Peter; Duquet, William; Van Gheluwe, Bart

2007-01-01

Sudden ankle inversion tests have been used to investigate whether the onset of peroneal muscle activity is delayed in patients with chronically unstable ankle joints. Before interpreting test results of latency times in patients with chronic ankle instability and healthy subjects, the reliability of these measures must be first demonstrated. To investigate the test-retest reliability of variables measured during a sudden ankle inversion movement in standing subjects with healthy ankle joints. Validation study. Research laboratory. 15 subjects with healthy ankle joints (30 ankles). Subjects stood on an ankle inversion platform with both feet tightly fixed to independently moveable trapdoors. An unexpected sudden ankle inversion of 50 degrees was imposed. We measured latency and motor response times and electromechanical delay of the peroneus longus muscle, along with the time and angular position of the first and second decelerating moments, the mean and maximum inversion speed, and the total inversion time. Correlation coefficients and standard error of measurements were calculated. Intraclass correlation coefficients ranged from 0.17 for the electromechanical delay of the peroneus longus muscle (standard error of measurement = 2.7 milliseconds) to 0.89 for the maximum inversion speed (standard error of measurement = 34.8 milliseconds). The reliability of the latency and motor response times of the peroneus longus muscle, the time of the first and second decelerating moments, and the mean and maximum inversion speed was acceptable in subjects with healthy ankle joints and supports the investigation of the reliability of these measures in subjects with chronic ankle instability. The lower reliability of the electromechanical delay of the peroneus longus muscle and the angular positions of both decelerating moments calls the use of these variables into question.

X-Ray Exam: Ankle

MedlinePlus

... Staying Safe Videos for Educators Search English Español X-Ray Exam: Ankle KidsHealth / For Parents / X-Ray Exam: Ankle What's in this article? What ... Have Questions Print What It Is An ankle X-ray is a safe and painless test that ...

Recurrence plots and recurrence quantification analysis of human motion data

NASA Astrophysics Data System (ADS)

Josiński, Henryk; Michalczuk, Agnieszka; Świtoński, Adam; Szczesna, Agnieszka; Wojciechowski, Konrad

2016-06-01

The authors present exemplary application of recurrence plots, cross recurrence plots and recurrence quantification analysis for the purpose of exploration of experimental time series describing selected aspects of human motion. Time series were extracted from treadmill gait sequences which were recorded in the Human Motion Laboratory (HML) of the Polish-Japanese Academy of Information Technology in Bytom, Poland by means of the Vicon system. Analysis was focused on the time series representing movements of hip, knee, ankle and wrist joints in the sagittal plane.

Anatomy and classification of the posterior tibial fragment in ankle fractures.

PubMed

Bartoníček, Jan; Rammelt, Stefan; Kostlivý, Karel; Vaněček, Václav; Klika, Daniel; Trešl, Ivo

2015-04-01

The aim of this study was to analyze the pathoanatomy of the posterior fragment on the basis of a comprehensive CT examination, including 3D reconstructions, in a large patient cohort. One hundred and forty one consecutive individuals with an ankle fracture or fracture-dislocation of types Weber B or Weber C and evidence of a posterior tibial fragment in standard radiographs were included in the study. The mean patient age was 49 years (range 19-83 years). The exclusion criteria were patients below 18 years of age, inability to provide written consent, fractures of the tibial pilon, posttraumatic arthritis and pre-existing deformities. In all patients, post-injury radiographs were obtained in anteroposterior, mortise and lateral views. All patients underwent CT scanning in transverse, sagittal and frontal planes. 3D CT reconstruction was performed in 91 patients. We were able to classify 137 cases into one of the following four types with constant pathoanatomic features: type 1: extraincisural fragment with an intact fibular notch, type 2: posterolateral fragment extending into the fibular notch, type 3: posteromedial two-part fragment involving the medial malleolus, type 4: large posterolateral triangular fragment. In the 4 cases it was not possible to classify the type of the posterior tibial fragment. These were collectively termed type 5 (irregular, osteoporotic fragments). It is impossible to assess the shape and size of the posterior malleolar fragment, involvement of the fibular notch, or the medial malleolus, on the basis of plain radiographs. The system that we propose for classification of fractures of the posterior malleolus is based on CT examination and takes into account the size, shape and location of the fragment, stability of the tibio-talar joint and the integrity of the fibular notch. It may be a useful indication for surgery and defining the most useful approach to these injuries.

Combined circular external fixation and open reduction internal fixation with pro-syndesmotic screws for repair of a diabetic ankle fracture

PubMed Central

Facaros, Zacharia; Ramanujam, Crystal L.; Stapleton, John J.

2010-01-01

The surgical management of ankle fractures among the diabetic population is associated with higher complication rates compared to the general population. Efforts toward development of better methods in prevention and treatment are continuously evolving for these injuries. The presence of peripheral neuropathy and the possible development of Charcot neuroarthropathy in this high risk patient population have stimulated much surgical interest to create more stable osseous constructs when open reduction of an ankle fracture/dislocation is required. The utilization of multiple syndesmotic screws (pro-syndesmotic screws) to further stabilize the ankle mortise has been reported by many foot and ankle surgeons. In addition, transarticular Steinmann pins have been described as an adjunct to traditional open reduction with internal fixation (ORIF) of the ankle to better stabilize the talus, thus minimizing risk of further displacement, malunion, and Charcot neuroarthropathy. The authors present a unique technique of ORIF with pro-syndesmotic screws and the application of a multi-plane circular external fixator for management of a neglected diabetic ankle fracture that prevented further deformity while allowing a weight-bearing status. This techniqu may be utilized for the management of complex diabetic ankle fractures that are prone to future complications and possible limb loss. PMID:22396812

Robotic cadaver testing of a new total ankle prosthesis model (German Ankle System).

PubMed

Richter, Martinus; Zech, Stefan; Westphal, Ralf; Klimesch, Yvone; Gosling, Thomas

2007-12-01

An investigation was carried out into possible increased forces, torques, and altered motions during load-bearing ankle motion after implantation of two different total ankle prostheses. We hypothesized that the parameters investigated would not differ in relation to the two implants compared. We included two different ankle prostheses (Hintegra, Newdeal, Vienne, France; German Ankle System, R-Innovation, Coburg, Germany). The prostheses were implanted in seven paired cadaver specimens. The specimens were mounted on an industrial robot that enables complex motion under predefined conditions (RX 90, Stäubli, Bayreuth, Germany). The robot detected the load-bearing (30 kg) motion of the 100(th) cycle of the specimens without prostheses as the baseline for the later testing, and mimicked that exact motion during 100 cycles after the prostheses were implanted. The resulting forces, torques, and bone motions were recorded and the differences between the prostheses compared. The Hintegra and German Ankle System, significantly increased the forces and torques in relation to the specimen without a prosthesis with one exception (one-sample-t-test, each p < or = 0.01; exception, parameter lateral force measured with the German Ankle System, p = 0.34). The force, torque, and motion differences between the specimens before and after implantation of the prostheses were lower with the German Ankle System than with the Hintegra (unpaired t-test, each p < or = 0.05). The German Ankle System prosthesis had less of an effect on resulting forces and torques during partial weightbearing passive ankle motion than the Hintegra prosthesis. This might improve function and minimize loosening during the clinical use.

Ankle Plantarflexor Spasticity Does Not Restrict the Recovery of Ankle Plantarflexor Strength or Ankle Power Generation for Push-Off During Walking Following Traumatic Brain Injury.

PubMed

Williams, Gavin; Banky, Megan; Olver, John

2016-01-01

The main aim of this project was to determine the impact of plantarflexor spasticity on muscle performance for ambulant people with traumatic brain injury (TBI). A large metropolitan rehabilitation hospital. Seventy-two ambulant people with TBI who were attending physiotherapy for mobility limitations. Twenty-four participants returned for a 6-month follow-up reassessment. Cross-sectional cohort study. Self-selected walking speed, Tardieu scale, ankle plantarflexor strength, and ankle power generation (APG). Participants with ankle plantarflexor spasticity had significantly lower self-selected walking speed; however, there was no significant difference in ankle plantarflexor strength or APG. Participants with ankle plantarflexor spasticity were not restricted in the recovery of self-selected walking speed, ankle plantarflexor strength, or APG, indicating equivalent ability to improve their mobility over time despite the presence of spasticity. Following TBI, people with ankle plantarflexor spasticity have significantly greater mobility limitations than those without spasticity, yet retain the capacity for recovery of self-selected walking speed, ankle plantarflexor strength, and APG.

Multiplanar lumbopelvic control in patients with low back pain: is multiplanar assessment better than single plane assessment in discriminating between patients and healthy controls?

PubMed

Nelson-Wong, E; Gallant, P; Alexander, S; Dehmer, K; Ingvalson, S; McClenahan, B; Piatte, A; Poupore, K; Davis, A M

2016-02-01

Patients with low back pain (LBP) commonly have lumbopelvic control deficits. Lumbopelvic assessment during sagittal motion is incorporated into commonly used clinical examination algorithms for Treatment Based Classification. The purpose of this study was to investigate whether combined assessment of lumbopelvic control during sagittal and frontal plane motion discriminates between people with and without LBP better than single plane assessment alone. Nineteen patients with LBP and 18 healthy control participants volunteered for this study. The active straight leg raise (ASLR) and active hip abduction (AHAbd) tests were used to assess lumbopelvic control during sagittal and frontal plane motion, respectively. The tests were scored as positive or negative using published scoring criteria. Contingency tables were created for each test alone and for the combined tests (both positive/both negative) with presence/absence of LBP as the reference standard to calculate accuracy statistics of sensitivity (sn), specificity (sp), likelihood (+LR and -LR), and diagnostic odds ratios (OR). Active straight leg raise and AHAbd tests alone had sn of 0·63, 0·74, respectively, sp of 0·61, 0·50, respectively, and OR of 2·7, 2·8, respectively. The combined tests had sn = 0·89, sp = 0·60, and OR = 12·0. Forty percent of patients with LBP had control deficits in both planes of motion. The AHAbd and ALSR tests appear to have greater diagnostic discrimination when used in combination than when used independently. A percentage of patients with LBP had control deficits in both planes, while others demonstrated uniplanar deficits only. These findings highlight the importance of multiplanar assessment in patients with LBP.

Joint Coordination and Muscle Activities of Ballet Dancers During Tiptoe Standing.

PubMed

Tanabe, Hiroko; Fujii, Keisuke; Kouzaki, Motoki

2017-01-01

We aimed to investigate joint coordination of lower limbs in dancers during tiptoe standing and the relationship between joint coordination and muscle coactivation. Seven female ballet dancers performed tiptoe standing with six leg positions (fi e classical dance positions and one modern dance position) for 10 s. The kinematic data of the metatarsophalangeal (MP), ankle, knee, and hip joints was collected, and surface electromyography (EMG) of over 13 lower limb muscles was conducted. Principal component analysis was performed to determine joint coordination. MP-ankle and ankle-knee had in-phase coordination, whereas knee-hip showed anti-phase coordination in the sagittal plane. In addition, most EMG-EMG coherence around the MP and ankle joints was significant up to 50 Hz when these two joints swayed with in-phase. This suggests that different joint coordination patterns are associated with neural processing related to different muscle coactivation patterns. In conclusion, ballet dancers showed in-phase coordination from the MP to knee joints, which was associated with muscle coactivation to a higher frequency domain (up to 50 Hz) in comparison with anti-phase coordination.

Contribution of ankle-foot orthosis moment in regulating ankle and knee motions during gait in individuals post-stroke.

PubMed

Kobayashi, Toshiki; Orendurff, Michael S; Singer, Madeline L; Gao, Fan; Foreman, K Bo

2017-06-01

Ankle-foot orthosis moment resisting plantarflexion has systematic effects on ankle and knee joint motion in individuals post-stroke. However, it is not known how much ankle-foot orthosis moment is generated to regulate their motion. The aim of this study was to quantify the contribution of an articulated ankle-foot orthosis moment to regulate ankle and knee joint motion during gait in individuals post-stroke. Gait data were collected from 10 individuals post-stroke using a Bertec split-belt instrumented treadmill and a Vicon 3-dimensional motion analysis system. Each participant wore an articulated ankle-foot orthosis whose moment resisting plantarflexion was adjustable at four levels. Ankle-foot orthosis moment while walking was calculated under the four levels based on angle-moment relationship of the ankle-foot orthosis around the ankle joint measured by bench testing. The ankle-foot orthosis moment and the joint angular position (ankle and knee) relationship in a gait cycle was plotted to quantify the ankle-foot orthosis moment needed to regulate the joint motion. Ankle and knee joint motion were regulated according to the amount of ankle-foot orthosis moment during gait. The ankle-foot orthosis maintained the ankle angular position in dorsiflexion and knee angular position in flexion throughout a gait cycle when it generated moment from -0.029 (0.011) to -0.062 (0.019) Nm/kg (moment resisting plantarflexion was defined as negative). Quantifying the contribution of ankle-foot orthosis moment needed to regulate lower limb joints within a specific range of motion could provide valuable criteria to design an ankle-foot orthosis for individuals post-stroke. Copyright © 2017 Elsevier Ltd. All rights reserved.

An uncommon ankle sprain.

PubMed

van Zoest, Wart J F; Janssen, Rob P A; Tseng, Carroll M E S

2007-11-01

Ankle sprain is the most frequently occurring acute injury in tennis, accounting for 20-25% of all injuries. In the current paper, we assess the cause of ankle sprain and suggest possibilities to be considered during diagnosis. We assessed a professional tennis player with a partial tear of the long peroneal tendon after an ankle sprain by physical exam, X-ray and MRI. Conservative treatment by means of soft cast and propriocepsis training led to full recovery. Peroneal tendon disorders must be part of the differential diagnosis after ankle sprain in the professional athlete.

Development of synthetic simulators for endoscope-assisted repair of metopic and sagittal craniosynostosis.

PubMed

Eastwood, Kyle W; Bodani, Vivek P; Haji, Faizal A; Looi, Thomas; Naguib, Hani E; Drake, James M

2018-06-01

OBJECTIVE Endoscope-assisted repair of craniosynostosis is a safe and efficacious alternative to open techniques. However, this procedure is challenging to learn, and there is significant variation in both its execution and outcomes. Surgical simulators may allow trainees to learn and practice this procedure prior to operating on an actual patient. The purpose of this study was to develop a realistic, relatively inexpensive simulator for endoscope-assisted repair of metopic and sagittal craniosynostosis and to evaluate the models' fidelity and teaching content. METHODS Two separate, 3D-printed, plastic powder-based replica skulls exhibiting metopic (age 1 month) and sagittal (age 2 months) craniosynostosis were developed. These models were made into consumable skull "cartridges" that insert into a reusable base resembling an infant's head. Each cartridge consists of a multilayer scalp (skin, subcutaneous fat, galea, and periosteum); cranial bones with accurate landmarks; and the dura mater. Data related to model construction, use, and cost were collected. Eleven novice surgeons (residents), 9 experienced surgeons (fellows), and 5 expert surgeons (attendings) performed a simulated metopic and sagittal craniosynostosis repair using a neuroendoscope, high-speed drill, rongeurs, lighted retractors, and suction/irrigation. All participants completed a 13-item questionnaire (using 5-point Likert scales) to rate the realism and utility of the models for teaching endoscope-assisted strip suturectomy. RESULTS The simulators are compact, robust, and relatively inexpensive. They can be rapidly reset for repeated use and contain a minimal amount of consumable material while providing a realistic simulation experience. More than 80% of participants agreed or strongly agreed that the models' anatomical features, including surface anatomy, subgaleal and subperiosteal tissue planes, anterior fontanelle, and epidural spaces, were realistic and contained appropriate detail. More

Assessment of Ankle Injuries

ERIC Educational Resources Information Center

Mai, Nicholas; Cooper, Leslie

2009-01-01

School nurses are faced with the challenge of identifying and treating ankle injuries in the school setting. There is little information guiding the assessment and treatment of these children when an injury occurs. It is essential for school nurses to understand ankle anatomy, pathophysiology of the acute ankle injury, general and orthopedic…

The path of the superior sagittal sinus in unicoronal synostosis.

PubMed

Russell, Aaron J; Patel, Kamlesh B; Skolnick, Gary; Woo, Albert S; Smyth, Matthew D

2014-10-01

This study investigates the anatomic relationship between the superior sagittal sinus (SSS) and the sagittal suture in infants with uncorrected unicoronal synostosis. The morphology of the SSS is also evaluated postoperatively to assess whether normalization of intracranial structures occurs following reconstruction. The study sample consisted of 20 computed tomography scans (10 preoperative, 6 postoperative, and 4 unaffected controls) obtained between 2001 and 2013. The SSS and the sagittal suture were outlined using Analyze imaging software. These data were used to measure the maximum lateral discrepancy between the SSS and the sagittal suture preoperatively and to assess for postoperative changes in the morphology of the SSS. In children with uncorrected unicoronal synostosis, the SSS deviates to the side of the patent coronal suture posteriorly and tends to follow the path of the sagittal and metopic sutures. The lateral discrepancy between the SSS and the sagittal suture ranged from 5.0 to 11.8 mm, with a 99.9 % upper prediction bound of 14.4 mm. Postoperatively, the curvature of the SSS was statistically decreased following surgical intervention, though it remained significantly greater than in unaffected controls. The SSS follows a predictable course relative to surface landmarks in children with unicoronal synostosis. When creating burr holes for craniotomies, the SSS can be avoided in 99.9 % of cases by remaining at least 14.4 mm from the lateral edge of the sagittal suture. Postoperative changes in the path of the SSS provide indirect evidence for normalization of regional brain morphology following fronto-orbital advancement.

Chronic Ankle Instability

MedlinePlus

... top of the talus is dome-shaped and... Softball Injuries to the Foot and Ankle Your feet ... ankles take a beating when you are playing softball. Softball players should be aware of the following ...

Ankle-Brachial Index

MedlinePlus

... in which the arteries in your legs or arms are narrowed or blocked. People with peripheral artery ... ankle with your blood pressure measured at your arm. A low ankle-brachial index number can indicate ...

Effect of External Ankle Support on Ankle and Knee Biomechanics During the Cutting Maneuver in Basketball Players.

PubMed

Klem, Nardia-Rose; Wild, Catherine Y; Williams, Sian A; Ng, Leo

2017-03-01

Despite the high prevalence of lower extremity injuries in female basketball players as well as a high proportion of athletes who wear ankle braces, there is a paucity of research pertaining to the effects of ankle bracing on ankle and knee biomechanics during basketball-specific tasks. To compare the effects of a lace-up brace (ASO), a hinged brace (Active T2), and no ankle bracing (control) on ankle and knee joint kinematics and joint reaction forces in female basketball athletes during a cutting maneuver. Controlled laboratory study. Twenty healthy, semi-elite female basketball players performed a cutting task under both ankle brace conditions (lace-up ankle brace and hinged ankle brace) and a no-brace condition. The 3-dimensional kinematics of the ankle and knee during the cutting maneuver were measured with an 18-camera motion analysis system (250 Hz), and ground-reaction force data were collected by use of a multichannel force plate (2000 Hz) to quantify ankle and knee joint reaction forces. Conditions were randomized using a block randomization method. Compared with the control condition, the hinged ankle brace significantly restricted peak ankle inversion (mean difference, 1.7°; P = .023). No significant difference was found between the lace-up brace and the control condition ( P = .865). Compared with the lace-up brace, the hinged brace significantly reduced ankle and knee joint compressive forces at the time of peak ankle dorsiflexion (mean difference, 1.5 N/kg [ P = .018] and 1.4 N/kg [ P = .013], respectively). Additionally, the hinged ankle brace significantly reduced knee anterior shear forces compared with the lace-up brace both during the deceleration phase and at peak ankle dorsiflexion (mean difference, 0.8 N/kg [ P = .018] and 0.9 N/kg [ P = .011], respectively). The hinged ankle brace significantly reduced ankle inversion compared with the no-brace condition and reduced ankle and knee joint forces compared with the lace-up brace in a female

Anterior ankle arthroscopy, distraction or dorsiflexion?

PubMed

de Leeuw, Peter A J; Golanó, Pau; Clavero, Joan A; van Dijk, C Niek

2010-05-01

Anterior ankle arthroscopy can basically be performed by two different methods; the dorsiflexion- or distraction method. The objective of this study was to determine the size of the anterior working area for both the dorsiflexion and distraction method. The anterior working area is anteriorly limited by the overlying anatomy which includes the neurovascular bundle. We hypothesize that in ankle dorsiflexion the anterior neurovascular bundle will move away anteriorly from the ankle joint, whereas in ankle distraction the anterior neurovascular bundle is pulled tight towards the joint, thereby decreasing the safe anterior working area. Six fresh frozen ankle specimens, amputated above the knee, were scanned with computed tomography. Prior to scanning the anterior tibial artery was injected with contrast fluid and subsequently each ankle was scanned both in ankle dorsiflexion and in distraction. A special device was developed to reproducibly obtain ankle dorsiflexion and distraction in the computed tomography scanner. The distance between the anterior border of the inferior tibial articular facet and the posterior border of the anterior tibial artery was measured. The median distance from the anterior border of the inferior tibial articular facet to the posterior border of the anterior tibial artery in ankle dorsiflexion and distraction was 0.9 cm (range 0.7-1.5) and 0.7 cm (range 0.5-0.8), respectively. The distance in ankle dorsiflexion significantly exceeded the distance in ankle distraction (P = 0.03). The current study shows a significantly increased distance between the anterior distal tibia and the overlying anterior neurovascular bundle with the ankle in a slightly dorsiflexed position as compared to the distracted ankle position. We thereby conclude that the distracted ankle position puts the neurovascular structures more at risk for iatrogenic damage when performing anterior ankle arthroscopy.

Anterior ankle arthroscopy, distraction or dorsiflexion?

PubMed Central

Golanó, Pau; Clavero, Joan A.; van Dijk, C. Niek

2010-01-01

Anterior ankle arthroscopy can basically be performed by two different methods; the dorsiflexion- or distraction method. The objective of this study was to determine the size of the anterior working area for both the dorsiflexion and distraction method. The anterior working area is anteriorly limited by the overlying anatomy which includes the neurovascular bundle. We hypothesize that in ankle dorsiflexion the anterior neurovascular bundle will move away anteriorly from the ankle joint, whereas in ankle distraction the anterior neurovascular bundle is pulled tight towards the joint, thereby decreasing the safe anterior working area. Six fresh frozen ankle specimens, amputated above the knee, were scanned with computed tomography. Prior to scanning the anterior tibial artery was injected with contrast fluid and subsequently each ankle was scanned both in ankle dorsiflexion and in distraction. A special device was developed to reproducibly obtain ankle dorsiflexion and distraction in the computed tomography scanner. The distance between the anterior border of the inferior tibial articular facet and the posterior border of the anterior tibial artery was measured. The median distance from the anterior border of the inferior tibial articular facet to the posterior border of the anterior tibial artery in ankle dorsiflexion and distraction was 0.9 cm (range 0.7–1.5) and 0.7 cm (range 0.5–0.8), respectively. The distance in ankle dorsiflexion significantly exceeded the distance in ankle distraction (P = 0.03). The current study shows a significantly increased distance between the anterior distal tibia and the overlying anterior neurovascular bundle with the ankle in a slightly dorsiflexed position as compared to the distracted ankle position. We thereby conclude that the distracted ankle position puts the neurovascular structures more at risk for iatrogenic damage when performing anterior ankle arthroscopy. PMID:20217392

Improved kinect-based spatiotemporal and kinematic treadmill gait assessment.

PubMed

Eltoukhy, Moataz; Oh, Jeonghoon; Kuenze, Christopher; Signorile, Joseph

2017-01-01

A cost-effective, clinician friendly gait assessment tool that can automatically track patients' anatomical landmarks can provide practitioners with important information that is useful in prescribing rehabilitative and preventive therapies. This study investigated the validity and reliability of the Microsoft Kinect v2 as a potential inexpensive gait analysis tool. Ten healthy subjects walked on a treadmill at 1.3 and 1.6m·s -1 , as spatiotemporal parameters and kinematics were extracted concurrently using the Kinect and three-dimensional motion analysis. Spatiotemporal measures included step length and width, step and stride times, vertical and mediolateral pelvis motion, and foot swing velocity. Kinematic outcomes included hip, knee, and ankle joint angles in the sagittal plane. The absolute agreement and relative consistency between the two systems were assessed using interclass correlations coefficients (ICC2,1), while reproducibility between systems was established using Lin's Concordance Correlation Coefficient (rc). Comparison of ensemble curves and associated 90% confidence intervals (CI90) of the hip, knee, and ankle joint angles were performed to investigate if the Kinect sensor could consistently and accurately assess lower extremity joint motion throughout the gait cycle. Results showed that the Kinect v2 sensor has the potential to be an effective clinical assessment tool for sagittal plane knee and hip joint kinematics, as well as some spatiotemporal temporal variables including pelvis displacement and step characteristics during the gait cycle. Copyright © 2016 Elsevier B.V. All rights reserved.

3.0T MR imaging of the ankle: Axial traction for morphological cartilage evaluation, quantitative T2 mapping and cartilage diffusion imaging-A preliminary study.

PubMed

Jungmann, Pia M; Baum, Thomas; Schaeffeler, Christoph; Sauerschnig, Martin; Brucker, Peter U; Mann, Alexander; Ganter, Carl; Bieri, Oliver; Rummeny, Ernst J; Woertler, Klaus; Bauer, Jan S

2015-08-01

To determine the impact of axial traction during high resolution 3.0T MR imaging of the ankle on morphological assessment of articular cartilage and quantitative cartilage imaging parameters. MR images of n=25 asymptomatic ankles were acquired with and without axial traction (6kg). Coronal and sagittal T1-weighted (w) turbo spin echo (TSE) sequences with a driven equilibrium pulse and sagittal fat-saturated intermediate-w (IMfs) TSE sequences were acquired for morphological evaluation on a four-point scale (1=best, 4=worst). For quantitative assessment of cartilage degradation segmentation was performed on 2D multislice-multiecho (MSME) SE T2, steady-state free-precession (SSFP; n=8) T2 and SSFP diffusion-weighted imaging (DWI; n=8) images. Wilcoxon-tests and paired t-tests were used for statistical analysis. With axial traction, joint space width increased significantly and delineation of cartilage surfaces was rated superior (P<0.05). Cartilage surfaces were best visualized on coronal T1-w images (P<0.05). Differences for cartilage matrix evaluation were smaller. Subchondral bone evaluation, motion artifacts and image quality were not significantly different between the acquisition methods (P>0.05). T2 values were lower at the tibia than at the talus (P<0.001). Reproducibility was better for images with axial traction. Axial traction increased the joint space width, allowed for better visualization of cartilage surfaces and improved compartment discrimination and reproducibility of quantitative cartilage parameters. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Ankle joint pressure changes in high tibial and distal femoral osteotomies: a cadaver study.

PubMed

Krause, F; Barandun, A; Klammer, G; Zderic, I; Gueorguiev, B; Schmid, T

2017-01-01

To assess the effect of high tibial and distal femoral osteotomies (HTO and DFO) on the pressure characteristics of the ankle joint. Varus and valgus malalignment of the knee was simulated in human cadaver full-length legs. Testing included four measurements: baseline malalignment, 5° and 10° re-aligning osteotomy, and control baseline malalignment. For HTO, testing was rerun with the subtalar joint fixed. In order to represent half body weight, a 300 N force was applied onto the femoral head. Intra-articular sensors captured ankle pressure. In the absence of restriction of subtalar movement, insignificant migration of the centre of force and changes of maximal pressure were seen at the ankle joint. With restricted subtalar motion, more significant lateralisation of the centre of force were seen with the subtalar joint in varus than in valgus position. Changes in maximum pressure were again not significant. The re-alignment of coronal plane knee deformities by HTO and DFO altered ankle pressure characteristics. When the subtalar joint was fixed in the varus position, migration of centre of force after HTO was more significant than when the subtalar joint was fixed in valgus. Cite this article: Bone Joint J 2017;99-B:59-65. ©2017 The British Editorial Society of Bone & Joint Surgery.

Design and development of a novel viscoelastic ankle-foot prosthesis based on the human ankle biomechanics.

PubMed

Safaeepour, Zahra; Esteki, Ali; Tabatabai Ghomshe, Farhad; Mousavai, Mohammad E

2014-10-01

In the present study, a new approach was applied to design and develop a viscoelastic ankle-foot prosthesis. The aim was to replicate the intact ankle moment-angle loop in the normal walking speed. The moment-angle loop of intact ankle was divided into four parts, and the appropriate models including two viscoelastic units of spring-damper mechanism were considered to replicate the passive ankle dynamics. The developed prototype was then tested on a healthy subject with the amputee gait simulator. The result showed that prosthetic ankle moment-angle loop was similar to that of intact ankle with the distinct four periods. The findings suggest that the prototype successfully provided the human ankle passive dynamics. Therefore, the viscoelastic units could imitate the four periods of a normal gait. The novel viscoelastic foot prosthesis could provide natural ankle dynamics in a gait cycle. Applying simple but biomechanical approach is suggested in conception of new designs for prosthetic ankle-foot mechanisms. © The International Society for Prosthetics and Orthotics 2014.

Effects of circumferential ankle pressure on ankle proprioception, stiffness, and postural stability: a preliminary investigation.

PubMed

You, Sung H; Granata, Kevin P; Bunker, Linda K

2004-08-01

Cross-sectional repeated-measures design. Determine the effects of circumferential ankle pressure (CAP) intervention on proprioceptive acuity, ankle stiffness, and postural stability. The application of CAP using braces, taping, and adaptive shoes or military boots is widely used to address chronic ankle instability (CAI). An underlying assumption is that the CAP intervention might improve ankle stability through increased proprioceptive acuity and stiffness in the ankle. METHOD AND MEASURES: A convenience sample of 10 subjects was recruited from the local university community and categorized according to proprioceptive acuity (high, low) and ankle stability (normal, CAI). Proprioceptive acuity was measured when blindfolded subjects were asked to accurately reproduce a self-selected target ankle position before and after the application of CAP. Proprioceptive acuity was determined in 5 different ankle joint position sense tests: neutral, inversion, eversion, plantar flexion, and dorsiflexion. Joint position angles were recorded electromechanically using a potentiometer. Passive ankle stiffness was computed from the ratio of applied static moment versus angular displacement. Active ankle stiffness was determined from biomechanical analyses of ankle motion following a mediolateral perturbation. Postural stability was quantified from the center of pressure displacement in the mediolateral and the anteroposterior directions in unipedal stance. All measurements were recorded with and without CAP applied by a pediatric blood pressure cuff. Data were analyzed using a separate mixed-model analysis of variance (ANOVA) for each dependent variable. Post hoc comparison using Tukey's honestly significant difference (HSD) test was performed if significant interactions were obtained. Significance level was set at P<.05 for all analyses. Significant group (high versus low proprioceptive acuity) x CAP interactions were identified for postural stability. Passive ankle stiffness was

All-inside, anatomical lateral ankle stabilization for revision and complex primary lateral ankle stabilization: a technique guide.

PubMed

Prissel, Mark A; Roukis, Thomas S

2014-12-01

Lateral ankle instability is a common mechanical problem that often requires surgical management when conservative efforts fail. Historically, myriad open surgical approaches have been proposed. Recently, consideration for arthroscopic management of lateral ankle instability has become popular, with promising results. Unfortunately, recurrent inversion ankle injury following lateral ankle stabilization can occur and require revision surgery. To date, arthroscopic management for revision lateral ankle stabilization has not been described. We present a novel arthroscopic technique combining an arthroscopic lateral ankle stabilization kit with a suture anchor ligament augmentation system for revision as well as complex primary lateral ankle stabilization. © 2014 The Author(s).

Contribution of lower limb eccentric work and different step responses to balance recovery among older adults.

PubMed

Nagano, Hanatsu; Levinger, Pazit; Downie, Calum; Hayes, Alan; Begg, Rezaul

2015-09-01

Falls during walking reflect susceptibility to balance loss and the individual's capacity to recover stability. Balance can be recovered using either one step or multiple steps but both responses are impaired with ageing. To investigate older adults' (n=15, 72.5±4.8 yrs) recovery step control a tether-release procedure was devised to induce unanticipated forward balance loss. Three-dimensional position-time data combined with foot-ground reaction forces were used to measure balance recovery. Dependent variables were; margin of stability (MoS) and available response time (ART) for spatial and temporal balance measures in the transverse and sagittal planes; lower limb joint angles and joint negative/positive work; and spatio-temporal gait parameters. Relative to multi-step responses, single-step recovery was more effective in maintaining balance, indicated by greater MoS and longer ART. MoS in the sagittal plane measure and ART in the transverse plane distinguished single step responses from multiple steps. When MoS and ART were negative (<0), balance was not secured and additional steps would be required to establish the new base of support for balance recovery. Single-step responses demonstrated greater step length and velocity and when the recovery foot landed, greater centre of mass downward velocity. Single-step strategies also showed greater ankle dorsiflexion, increased knee maximum flexion and more negative work at the ankle and knee. Collectively these findings suggest that single-step responses are more effective in forward balance recovery by directing falling momentum downward to be absorbed as lower limb eccentric work. Copyright © 2015 Elsevier B.V. All rights reserved.

Anterior ankle impingement syndromes.

PubMed

Umans, Hilary R; Cerezal, Luiz

2008-06-01

Ankle impingement syndromes are painful conditions that may complicate ankle trauma and are characterized by chronic, progressive pain, swelling, and limitation of movement. These disorders are subclassified according to anatomical location about the tibiotalar joint. This article reviews the various forms of anterior ankle impingement, detailing the unique clinical features, anatomical considerations, pathoetiology, and imaging findings for each.

Upper ankle joint space detection on low contrast intraoperative fluoroscopic C-arm projections

NASA Astrophysics Data System (ADS)

Thomas, Sarina; Schnetzke, Marc; Brehler, Michael; Swartman, Benedict; Vetter, Sven; Franke, Jochen; Grützner, Paul A.; Meinzer, Hans-Peter; Nolden, Marco

2017-03-01

Intraoperative mobile C-arm fluoroscopy is widely used for interventional verification in trauma surgery, high flexibility combined with low cost being the main advantages of the method. However, the lack of global device-to- patient orientation is challenging, when comparing the acquired data to other intrapatient datasets. In upper ankle joint fracture reduction accompanied with an unstable syndesmosis, a comparison to the unfractured contralateral site is helpful for verification of the reduction result. To reduce dose and operation time, our approach aims at the comparison of single projections of the unfractured ankle with volumetric images of the reduced fracture. For precise assessment, a pre-alignment of both datasets is a crucial step. We propose a contour extraction pipeline to estimate the joint space location for a prealignment of fluoroscopic C-arm projections containing the upper ankle joint. A quadtree-based hierarchical variance comparison extracts potential feature points and a Hough transform is applied to identify bone shaft lines together with the tibiotalar joint space. By using this information we can define the coarse orientation of the projections independent from the ankle pose during acquisition in order to align those images to the volume of the fractured ankle. The proposed method was evaluated on thirteen cadaveric datasets consisting of 100 projections each with manually adjusted image planes by three trauma surgeons. The results show that the method can be used to detect the joint space orientation. The correlation between angle deviation and anatomical projection direction gives valuable input on the acquisition direction for future clinical experiments.

Reliability of the Phi angle to assess rotational alignment of the talar component in total ankle replacement.

PubMed

Manzi, Luigi; Villafañe, Jorge Hugo; Indino, Cristian; Tamini, Jacopo; Berjano, Pedro; Usuelli, Federico Giuseppe

2017-11-08

The purpose of this study was to investigate the test-retest reliability of the Phi angle in patients undergoing total ankle replacement (TAR) for end stage ankle osteoarthritis (OA) to assess the rotational alignment of the talar component. Retrospective observational cross-sectional study of prospectively collected data. Post-operative anteroposterior radiographs of the foot of 170 patients who underwent TAR for the ankle OA were evaluated. Three physicians measured Phi on the 170 randomly sorted and anonymized radiographs on two occasions, one week apart (test and retest conditions), inter and intra-observer agreement were evaluated. Test-retest reliability of Phi angle measurement was excellent for patients with Hintegra TAR (ICC=0.995; p<0.001) and Zimmer TAR (ICC=0.995; p<0.001) on radiographs of subjects with ankle OA. There were no significant differences in the reliability of the Phi angle measurement between patients with Hintegra vs. Zimmer implants (p>0.05). Measurement of Phi angle on weight-bearing dorsoplantar radiograph showed an excellent reliability among orthopaedic surgeons in determining the position of the talar component in the axial plane. Level II, cross sectional study. Copyright © 2017 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

An uncommon ankle sprain

PubMed Central

van Zoest, Wart J F; Janssen, Rob P A; Tseng, Carroll M E S

2007-01-01

Objective Ankle sprain is the most frequently occurring acute injury in tennis, accounting for 20–25% of all injuries. In the current paper, we assess the cause of ankle sprain and suggest possibilities to be considered during diagnosis. Methods We assessed a professional tennis player with a partial tear of the long peroneal tendon after an ankle sprain by physical exam, X‐ray and MRI. Results Conservative treatment by means of soft cast and propriocepsis training led to full recovery. Conclusion Peroneal tendon disorders must be part of the differential diagnosis after ankle sprain in the professional athlete. PMID:17957026

Ankle ligament healing after an acute ankle sprain: an evidence-based approach.

PubMed

Hubbard, Tricia J; Hicks-Little, Charlie A

2008-01-01

To perform a systematic review to determine the healing time of the lateral ankle ligaments after an acute ankle sprain. We identified English-language research studies from 1964 to 2007 by searching MEDLINE, Physiotherapy Evidence Database (PEDro), SportDiscus, and CINAHL using the terms ankle sprain, ankle rehabilitation, ankle injury, ligament healing, and immobilization. We selected studies that described randomized, controlled clinical trials measuring ligament laxity either objectively or subjectively immediately after injury and at least 1 more time after injury. Two reviewers independently scored the 7 studies that met the inclusion criteria. Because of differences in study designs, a meta-analysis could not be performed. Effect sizes and confidence intervals could be calculated only for 1 study. The percentages of subjective and objective instability were calculated for the remaining studies. Ankle laxity improved over a period of 6 weeks to 1 year. One author showed stress talar tilt values of 16.10 +/- 8.8 degrees immediately after injury and 3.4 +/- 3.6 degrees at 3 months after injury. In 2 articles, the authors reported that positive anterior drawer tests were still present in 3% to 31% of participants at 6 months after injury. Additionally, feelings of instability affected 7% to 42% of participants up to 1 year after injury. In the studies that we examined, it took at least 6 weeks to 3 months before ligament healing occurred. However, at 6 weeks to 1 year after injury, a large percentage of participants still had objective mechanical laxity and subjective ankle instability. Direct comparison among articles is difficult because of differences in methods. More research focusing on more reliable methods of measuring ankle laxity is needed so that clinicians can know how long ligament healing takes after injury. This knowledge will help clinicians to make better decisions during rehabilitation and for return to play.

Chronic musculoskeletal ankle disorders in Sri Lanka.

PubMed

Weerasekara, Ishanka; Hiller, Claire E

2017-05-25

Musculoskeletal disorders of the lower extremities are commonly affected by chronicity and disability. One of the most commonly affected areas is the ankle. Epidemiological information is limited for chronic musculoskeletal ankle disorders in the general community, particularly in the developing world. This study aimed to determine the prevalence and impact of chronic musculoskeletal ankle disorders in the Sri Lankan community. A cross-sectional stratified random sample of people (n = 1000) aged 18 to 85 years in Sri Lanka was undertaken by questionnaire in the general community setting. Of those questionnaires, 827 participants provided data. Point prevalence for no history of ankle injury or ankle disorders, history of ankle injuries without chronic ankle disorders, and chronic ankle disorders were obtained. Point prevalence of chronic musculoskeletal disorders and causes for chronicity was evaluated. There were 448 (54.2%) participants with no ankle disorders, 164 (19.8%) with a history of ankle injury but no chronic disorders, and 215 (26.0%) with chronic ankle disorders. The major component of chronic ankle disorders was musculoskeletal disorders (n = 113, 13.7% of the total sample), most of which were due to ankle injury (n = 80, 9.7% of the total). Sprains were responsible for 17.7% of the total ankle injuries. Arthritis was the other main cause for chronicity of ankle disorders with 4% of total participants (n = 33). Almost 14% of the Sri Lankan community was affected by chronic musculoskeletal ankle disorders. The majority were due to a previous ankle injury, and arthritis. Most people had to limit or change their physical activity because of the chronic ankle disorder. A very low utility of physiotherapy services was observed.

Total ankle arthroplasty versus ankle arthrodesis. Comparison of sports, recreational activities and functional outcome.

PubMed

Schuh, Reinhard; Hofstaetter, Jochen; Krismer, Martin; Bevoni, Roberto; Windhager, Reinhard; Trnka, Hans-Joerg

2012-06-01

Ankle arthrodesis (AAD) and total ankle replacement (TAR) are the major surgical treatment options for severe ankle arthritis. There is an ongoing discussion in the orthopaedic community whether ankle arthrodesis or ankle fusion should be the treatment of choice for end stage osteoarthritis. The purpose of this study was to compare the participation in sports and recreational activities in patients who underwent either AAD or TAR for end-stage osteoarthritis of the ankle. A total of 41 patients (21 ankle arthrodesis /20 TAR) were examined at 34.5 (SD18.0) months after surgery. At follow-up, pre- and postoperative participation in sports and recreational activities has been assessed. Activity levels were determined using the ankle activity score according to Halasi et al. and the University of California at Los Angeles (UCLA) activity scale. Clinical and functional outcome was assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score. The percentage of patients participating in sports and recreational activities, UCLA score and AOFAS score were compared between both treatment groups. In the AAD group 86% were active in sports preoperatively and in the TAR group this number was 76%. Postoperatively in both groups 76% were active in sports (AAD, p = 0.08). The UCLA score was 7.0 (± 1.9) in the AAD group and 6.8 (± 1.8) in the TAR group (p = 0.78). The AOFAS score reached 75.6 (± 14) in the AAD group and 75.6 (± 16) in the TAR group (p = 0.97). The ankle activity score decrease was statistically significant for both groups (p = 0.047). Our study revealed no significant difference between the groups concerning activity levels, participation in sports activities, UCLA and AOFAS score. After AAD the number of patients participating in sports decreased. However, this change was not statistically significant.

Anterior ankle arthrodesis

PubMed Central

Slater, Gordon L; Sayres, Stephanie C; O’Malley, Martin J

2014-01-01

Ankle arthrodesis is a common procedure that resolves many conditions of the foot and ankle; however, complications following this procedure are often reported and vary depending on the fixation technique. Various techniques have been described in the attempt to achieve ankle arthrodesis and there is much debate as to the efficiency of each one. This study aims to evaluate the efficiency of anterior plating in ankle arthrodesis using customised and Synthes TomoFix plates. We present the outcomes of 28 ankle arthrodeses between 2005 and 2012, specifically examining rate of union, patient-reported outcomes scores, and complications. All 28 patients achieved radiographic union at an average of 36 wk; the majority of patients (92.86%) at or before 16 wk, the exceptions being two patients with Charcot joints who were noted to have bony union at a three year review. Patient-reported outcomes scores significantly increased (P < 0.05). Complications included two delayed unions as previously mentioned, infection, and extended postoperative pain. With multiple points for fixation and coaxial screw entry points, the contoured customised plate offers added compression and provides a rigid fixation for arthrodesis stabilization. PMID:24649408

Ankle Sprains. A Round Table.

ERIC Educational Resources Information Center

Physician and Sportsmedicine, 1986

1986-01-01

Types of ankle sprains, surgical versus nonsurgical treatment, tape versus brace for support, rehabilitation, exercise, and prevention of ankle sprains are discussed by a panel of experts. An acute ankle taping technique is illustrated. (MT)

Gait kinematics and kinetics of 7-year-old children: a comparison to adults using age-specific anthropometric data.

PubMed

Ganley, Kathleen J; Powers, Christopher M

2005-02-01

The purpose of this study was to determine if sagittal plane gait kinematics and kinetics of 7-year-old children differed from those of adults when age-specific anthropometrics were used in the calculations. Joint angles, moments, and power obtained during level walking in 7-year-old children (n=15) were compared to data from adults (n=15). Calculations were performed using age-specific anthropometric data obtained from dual energy X-ray absorptiometry. For most of the variables examined, 7-year-olds were similar to adults, however children demonstrated a diminished peak plantar flexor moment and less peak power absorption and generation at the ankle during late stance. These results provide support for the hypothesis that children lack the neuromuscular maturity, especially at the ankle, to produce an adult-like gait pattern.

Role of Ankle Arthroscopy in Management of Acute Ankle Fracture.

PubMed

Chan, Kwok Bill; Lui, Tun Hing

2016-11-01

To report the operative findings of ankle arthroscopy during open reduction and internal fixation of acute ankle fractures. This was a retrospective review of 254 consecutive patients with acute ankle fractures who were treated with open reduction and internal fixation of the fractures, and ankle arthroscopy was performed at the same time. The accuracy of fracture reduction, the presence of syndesmosis disruption and its reduction, and the presence of ligamentous injuries and osteochondral lesions were documented. Second-look ankle arthroscopy was performed during syndesmosis screw removal 6 weeks after the key operation. There were 6 patients with Weber A, 177 patients with Weber B, 51 patients with Weber C, and 20 patients with isolated medial malleolar fractures. Syndesmosis disruption was present in 0% of patients with Weber A fracture, 52% of patients with Weber B fracture, 92% of patients with Weber C fracture, and 20% of the patients with isolated medial malleolar fracture. Three patients with Weber B and one patient with Weber C fracture have occult syndesmosis instability after screw removal. Osteochondral lesion was present in no patient with Weber A fracture, 26% of the Weber B cases, 24% of the Weber C cases, and 20% of isolated medial malleolar fracture cases. The association between the presence of deep deltoid ligament tear and syndesmosis disruption (warranting syndesmosis screw fixation) in Weber B cases was statistically significant but not in Weber C cases. There was no statistically significant association between the presence of posterior malleolar fracture and syndesmosis instability that warrant screw fixation. Ankle arthroscopy is a useful adjuvant tool to understand the severity and complexity of acute ankle fracture. Direct arthroscopic visualization ensures detection and evaluation of intra-articular fractures, syndesmosis disruption, and associated osteochondral lesions and ligamentous injuries. Level IV, case series

The influence of knee alignment on lower extremity kinetics during squats.

PubMed

Slater, Lindsay V; Hart, Joseph M

2016-12-01

The squat is an assessment of lower extremity alignment during movement, however there is little information regarding altered joint kinetics during poorly performed squats. The purpose of this study was to examine changes in joint kinetics and power from altered knee alignment during a squat. Thirty participants completed squats while displacing the knee medially, anteriorly, and with neutral alignment (control). Sagittal and frontal plane torques at the ankle, knee, and hip were altered in the descending and ascending phase of the squat in both the medial and anterior malaligned squat compared to the control squat. Ankle and trunk power increased and hip power decreased in the medial malaligned squat compared to the control squat. Ankle, knee, and trunk power increased and hip power decreased in the anterior malaligned squat compared to the control squat. Changes in joint torques and power during malaligned squats suggest that altered knee alignment increases ankle and trunk involvement to execute the movement. Increased anterior knee excursion during squatting may also lead to persistent altered loading of the ankle and knee. Sports medicine professionals using the squat for quadriceps strengthening must consider knee alignment to reduce ankle and trunk involvement during the movement. Copyright © 2016 Elsevier Ltd. All rights reserved.

Transfibular ankle arthrodesis: A novel method for ankle fusion – A short term retrospective study

PubMed Central

Balaji, S Muthukumar; Selvaraj, V; Devadoss, Sathish; Devadoss, Annamalai

2017-01-01

Background: Ankle arthrodesis has long been the traditional operative treatment for posttraumatic arthritis, rheumatoid arthritis, infection, neuromuscular conditions, and salvage of failed ankle arthroplasty. It remains the treatment of choice for patients in whom heavy and prolonged activity is anticipated. We present our short term followup study of functional outcome of patients who underwent transfibular ankle arthrodesis for arthritis of ankle due to various indications. Materials and Methods: 29 transfibular ankle arthrodesis in 29 patients performed between April 2009 and April 2014 were included in this study. The mean age was 50 years (range 22-75 years). The outcome analysis with a minimum of 1-year postoperative followup were included. All the patients were assessed with the American Orthopaedic Foot and Ankle Society (AOFAS) Hindfoot scale. Results: All cases of ankle fusions (100%) progressed to solid union in a mean postoperative duration of 3.8 months (range 3–6 months). All patients had sound arthrodesis. The mean followup period was 32.52 months (standard deviation ± 10.34). The mean AOFAS score was 74 (pain score = 32, functional score = 42). We found that twenty patients (68.96%) out of 29, had excellent results, 7 (24.13%) had good, and 2 (6.89%) showed fair results. Conclusion: Transfibular ankle arthrodesis is a simple and effective procedure for ankle arthritis. It achieves a high rate of union and good functional outcome on midterm followup. PMID:28216754

Spring-like Ankle Foot Orthoses reduce the energy cost of walking by taking over ankle work.

PubMed

Bregman, D J J; Harlaar, J; Meskers, C G M; de Groot, V

2012-01-01

In patients with central neurological disorders, gait is often limited by a reduced ability to push off with the ankle. To overcome this reduced ankle push-off, energy-storing, spring-like carbon-composite Ankle Foot Orthoses (AFO) can be prescribed. It is expected that the energy returned by the AFO in late stance will support ankle push-off, and reduce the energy cost of walking. In 10 patients with multiple sclerosis and stroke the energy cost of walking, 3D kinematics, joint power, and joint work were measured during gait, with and without the AFO. The mechanical characteristics of the AFO were measured separately, and used to calculate the contribution of the AFO to the ankle kinetics. We found a significant decrease of 9.8% in energy cost of walking when walking with the AFO. With the AFO, the range of motion of the ankle was reduced by 12.3°, and the net work around the ankle was reduced by 29%. The total net work in the affected leg remained unchanged. The AFO accounted for 60% of the positive ankle work, which reduced the total amount of work performed by the leg by 11.1% when walking with the AFO. The decrease in energy cost when walking with a spring-like energy-storing AFO in central neurological patients is not induced by an augmented net ankle push-off, but by the AFO partially taking over ankle work. Copyright © 2011 Elsevier B.V. All rights reserved.

The improvement of postural control in patients with mechanical ankle instability after lateral ankle ligaments reconstruction.

PubMed

Li, Hong-Yun; Zheng, Jie-Jiao; Zhang, Jian; Cai, Ye-Hua; Hua, Ying-Hui; Chen, Shi-Yi

2016-04-01

Lateral ankle sprain is the most common injury. A previous study demonstrated that patients with mechanical ankle instability suffered deficits in postural control, indicating that structural damage of the lateral ankle ligaments may produce a balance deficit. The purpose of this study was to confirm that lateral ligaments reconstruction could improve postural control in patients with mechanical ankle instability. A total of 15 patients were included in the study. Each patient had a history of an ankle sprain with persistent symptoms of ankle instability and a positive anterior drawer test and had been treated nonoperatively for at least 3 months. All patients were diagnosed with lateral ankle ligaments tear by ultrasonography and magnetic resonance imaging. They underwent arthroscopic debridement and open lateral ankle ligaments reconstruction with a modified Broström procedure. One day before and 6 months after the operation, all of the participants underwent single-limb postural sway tests. The anterior drawer test and the American Orthopedic Foot and Ankle Society scale score were used to evaluate the clinical results in these patients. At 6 months after the operation, with the patients' eyes closed, there was significantly decreased postural sway in the anteroposterior direction, the circumferential area, and the total path length on the operated ankles compared with those measurements before the operation. With eyes open, however, no difference was found in postural sway before and after the operation. Postural control was improved by reconstructing the lateral ligaments. IV.

Acute ankle sprain in dancers.

PubMed

Russell, Jeffrey A

2010-01-01

Ankle sprain is a common injury in dancers. Because of the relative frequency of this injury and its wide acceptance as a likely part of an active lifestyle, in many individuals it may not receive the careful attention it deserves. An extreme ankle range of motion and excellent ankle stability are fundamental to success in dance. Hence, following a proper treatment protocol is crucial for allowing a dancer who suffers an ankle sprain to return to dance as soon as possible without impaired function. This article reviews the basic principles of the etiology and management of ankle sprain in dancers. Key concepts are on-site examination and treatment, early restoration, dance-specific rehabilitation, and a carefully administered safe return to dance. Additionally, injuries that may occur in conjunction with ankle sprain are highlighted, and practical, clinically relevant summary concepts for dance healthcare professionals, dance scientists, dance teachers, and dancers are provided.

Effects of Neuromuscular Training on the Rear-foot Angle Kinematics in Elite Women Field Hockey Players with Chronic Ankle Instability

PubMed Central

Kim, Eunkuk; Choi, Hokyung; Cha, Jung-Hoon; Park, Jong-Chul; Kim, Taegyu

2017-01-01

The aims of this study were to investigate the ankle position, the changes and persistence of ankle kinematics after neuromuscular training in athletes with chronic ankle instability (CAI). A total of 21 national women’s field hockey players participated (CAI = 12, control = 9). Ankle position at heel strike (HS), midstance (MS), and toe touch (TT) in the frontal plane during walking, running and landing were measured using 3D motion analysis. A 6-week neuromuscular training program was undertaken by the CAI group. Measurements of kinematic data for both groups were measured at baseline and the changes in kinematic data for CAI group were measured at 6 and 24 weeks. The kinematic data at HS during walking and running demonstrated that the magnitude of the eversion in the CAI group (−5.00° and −4.21°) was less than in the control group (−13.45°and −9.62°). The kinematic data at MS also exhibited less ankle eversion in the CAI group (−9.36° and −8.18°) than in the control group (−18.52° and −15.88°). Ankle positions at TT during landing were comparable between groups. Following the 6-week training, the CAI participants demonstrated a less everted ankle at HS during walking and running (−1.77° and −1.76°) compared to the previous positions. They also showed less ankle eversion at MS (−5.14° and −4.19°). Ankle orientation at TT changed significantly to an inverted ankle position (from −0.26° to 4.11°). The ankle kinematics were restored back to the previous positions at 24 weeks except for landing. It appeared that athletes with unstable ankle had a relatively inverted ankle position, and that 6-week neuromuscular training had an immediate effect on changing ankle orientation toward a less everted direction. The changed ankle kinematics seemed to persist during landing but not during walking and running. Key points Athletes with unstable ankles had a relatively inverted ankle position during the initial contact and midstance

Characterizing head motion in three planes during combined visual and base of support disturbances in healthy and visually sensitive subjects.

PubMed

Keshner, E A; Dhaher, Y

2008-07-01

Multiplanar environmental motion could generate head instability, particularly if the visual surround moves in planes orthogonal to a physical disturbance. We combined sagittal plane surface translations with visual field disturbances in 12 healthy (29-31 years) and 3 visually sensitive (27-57 years) adults. Center of pressure (COP), peak head angles, and RMS values of head motion were calculated and a three-dimensional model of joint motion was developed to examine gross head motion in three planes. We found that subjects standing quietly in front of a visual scene translating in the sagittal plane produced significantly greater (p<0.003) head motion in yaw than when on a translating platform. However, when the platform was translated in the dark or with a visual scene rotating in roll, head motion orthogonal to the plane of platform motion significantly increased (p<0.02). Visually sensitive subjects having no history of vestibular disorder produced large, delayed compensatory head motion. Orthogonal head motions were significantly greater in visually sensitive than in healthy subjects in the dark (p<0.05) and with a stationary scene (p<0.01). We concluded that motion of the visual field could modify compensatory response kinematics of a freely moving head in planes orthogonal to the direction of a physical perturbation. These results suggest that the mechanisms controlling head orientation in space are distinct from those that control trunk orientation in space. These behaviors would have been missed if only COP data were considered. Data suggest that rehabilitation training can be enhanced by combining visual and mechanical perturbation paradigms.

[Ankle arthrodesis with interposition graft as a salvage procedure after failed total ankle replacement].

PubMed

Schill, Stephan

2007-12-01

Restoration of painless function to the lower limb by ankle fusion after failure of total ankle arthroplasty. Loose total ankle replacement. Severe ankle destruction and axial deviation in rheumatoid patients. Severe osteoarthritis in the subtalar and ankle joints. Infected total ankle replacement. Severe arterial occlusive disease of the affected extremity. Transfibular approach to the subtalar and ankle joints. Osteotomy and resection of the distal fibula 7-8 cm proximal to the tip of the lateral malleolus. Removal of the prosthetic components, synovectomy, and revitalization of the remaining bone surface. Removal of any residual articular cartilage from the subtalar joint surfaces. Determination of the extent of bone loss and defect filling with horizontally or vertically placed tricortical and cancellous bone graft from the resected fibula and, if necessary, from the ipsilateral anterior iliac crest. Tibiotalocalcaneal arthrodesis by retrograde insertion of a retrograde locking nail. Wound closure in layers. Split below-knee cast. Mobilization with below-knee cast without weight bearing for 6 weeks. Dynamic locking of the intramedullary nail. Partial weight bearing with a walker up to 20 kg for an additional 6 weeks. Gradual increase in weight bearing in accordance with radiologic evidence of consolidation. Fitted orthopedic shoe with rocker-bottom sole, and made to measure insoles. From January 2003 to September 2006, 15 patients with infected ankle prosthesis loosening (six Thompson-Richards prostheses, eight S.T.A.R. prostheses, and one Salto prosthesis) were treated. All patients underwent tibiotalocalcaneal interposition arthrodesis with femoral nailing in retrograde technique. The average AOFAS (American Orthopaedic Foot and Ankle Society) Score was 57.9 points (35-81 points) postoperatively. One patient developed a nonunion and revision surgery will have to be performed. Another patient with delayed wound healing and skin necrosis needed plastic surgery.

Altered knee and ankle kinematics during squatting in those with limited weight-bearing-lunge ankle-dorsiflexion range of motion.

PubMed

Dill, Karli E; Begalle, Rebecca L; Frank, Barnett S; Zinder, Steven M; Padua, Darin A

2014-01-01

Ankle-dorsiflexion (DF) range of motion (ROM) may influence movement variables that are known to affect anterior cruciate ligament loading, such as knee valgus and knee flexion. To our knowledge, researchers have not studied individuals with limited or normal ankle DF-ROM to investigate the relationship between those factors and the lower extremity movement patterns associated with anterior cruciate ligament injury. To determine, using 2 different measurement techniques, whether knee- and ankle-joint kinematics differ between participants with limited and normal ankle DF-ROM. Cross-sectional study. Sports medicine research laboratory. Forty physically active adults (20 with limited ankle DF-ROM, 20 with normal ankle DF-ROM). Ankle DF-ROM was assessed using 2 techniques: (1) nonweight-bearing ankle DF-ROM with the knee straight, and (2) weight-bearing lunge (WBL). Knee flexion, knee valgus-varus, knee internal-external rotation, and ankle DF displacements were assessed during the overhead-squat, single-legged squat, and jump-landing tasks. Separate 1-way analyses of variance were performed to determine whether differences in knee- and ankle-joint kinematics existed between the normal and limited groups for each assessment. We observed no differences between the normal and limited groups when classifying groups based on nonweight-bearing passive-ankle DF-ROM. However, individuals with greater ankle DF-ROM during the WBL displayed greater knee-flexion and ankle-DF displacement and peak knee flexion during the overhead-squat and single-legged squat tasks. In addition, those individuals also demonstrated greater knee-varus displacement during the single-legged squat. Greater ankle DF-ROM assessed during the WBL was associated with greater knee-flexion and ankle-DF displacement during both squatting tasks as well as greater knee-varus displacement during the single-legged squat. Assessment of ankle DF-ROM using the WBL provided important insight into compensatory

Prospective Computed Tomographic Analysis of Osteochondral Lesions of the Ankle Joint Associated With Ankle Fractures.

PubMed

Nosewicz, Tomasz L; Beerekamp, M Suzan H; De Muinck Keizer, Robert-Jan O; Schepers, Tim; Maas, Mario; Niek van Dijk, C; Goslings, J Carel

2016-08-01

Osteochondral lesions (OCLs) associated with ankle fracture correlate with unfavorable outcome. The goals of this study were to detect OCLs following ankle fracture, to associate fracture type to OCLs and to investigate whether OCLs affect clinical outcome. 100 ankle fractures requiring operative treatment were prospectively included (46 men, 54 women; mean age 44 ± 14 years, range 20-77). All ankle fractures (conventional radiography; 71 Weber B, 22 Weber C, 1 Weber A, 4 isolated medial malleolus and 2 isolated posterior malleolus fractures) were treated by open reduction and internal fixation. Multidetector computed tomography (CT) was performed postoperatively. For each OCL, the location, size, and Loomer OCL classification (CT modified Berndt and Harty classification) were determined. The subjective Foot and Ankle Outcome Scoring (FAOS) was used for clinical outcome at 1 year. OCLs were found in 10/100 ankle fractures (10.0%). All OCLs were solitary talar lesions. Four OCLs were located posteromedial, 4 posterolateral, 1 anterolateral, and 1 anteromedial. There were 2 type I OCLs (subchondral compression), 6 type II OCLs (partial, nondisplaced fracture) and 2 type IV OCLs (displaced fracture). Mean OCL size (largest diameter) was 4.4 ± 1.7 mm (range, 1.7 mm to 6.2 mm). Chi-square analysis showed no significant association between ankle fracture type and occurrence of OCLs. OCLs did occur only in Lauge-Hansen stage III/IV ankle fractures. There were no significant differences in FAOS outcome between patients with or without OCLs. Ten percent of investigated ankle fractures had associated OCLs on CT. Although no significant association between fracture type and OCL was found, OCLs only occurred in Lauge-Hansen stage III/IV ankle fractures. With the numbers available, OCLs did not significantly affect clinical outcome at 1 year according to FAOS. Level IV, observational study. © The Author(s) 2016.

Retrospective comparison of the Low Risk Ankle Rules and the Ottawa Ankle Rules in a pediatric population.

PubMed

Ellenbogen, Amy L; Rice, Amy L; Vyas, Pranav

2017-09-01

A recent multicenter prospective Canadian study presented prospective evidence supporting the Low Risk Ankle Rules (LRAR) as a means of reducing the number of ankle radiographs ordered for children presenting with an ankle injury while maintaining nearly 100% sensitivity. This is in contrast to a previous prospective study which showed that this rule yielded only 87% sensitivity. It is important to further investigate the LRAR and compare them with the already validated Ottawa Ankle Rules (OAR) to potentially curb healthcare costs and decrease unnecessary radiation exposure without compromising diagnostic accuracy. We conducted a retrospective chart review of 980 qualifying patients ages 12months to 18years presenting with ankle injury to a commonly staffed 310 bed children's hospital and auxiliary site pediatric emergency department. There were 28 high-risk fractures identified. The Ottawa Ankle Rules had a sensitivity of 100% (95% CI 87.7-100), specificity of 33.1% (95% CI 30.1-36.2), and would have reduced the number of ankle radiographs ordered by 32.1%. The Low Risk Ankle Rules had a sensitivity of 85.7% (95% CI 85.7-96), specificity of 64.9% (95% CI 61.8-68), and would have reduced the number of ankle radiographs ordered by 63.1%. The latter rule missed 4 high-risk fractures. The Low Risk Ankle Rules may not be sensitive enough for use in Pediatric Emergency Departments, while the Ottawa Ankle Rules again demonstrated 100% sensitivity. Further research on ways to implement the Ottawa Ankle Rules and maximize its ability to decrease wait times, healthcare costs, and improve patient satisfaction are needed. Copyright © 2017 Elsevier Inc. All rights reserved.

A three-dimensional model to assess the effect of ankle joint axis misalignments in ankle-foot orthoses.

PubMed

Fatone, Stefania; Johnson, William Brett; Tucker, Kerice

2016-04-01

Misalignment of an articulated ankle-foot orthosis joint axis with the anatomic joint axis may lead to discomfort, alterations in gait, and tissue damage. Theoretical, two-dimensional models describe the consequences of misalignments, but cannot capture the three-dimensional behavior of ankle-foot orthosis use. The purpose of this project was to develop a model to describe the effects of ankle-foot orthosis ankle joint misalignment in three dimensions. Computational simulation. Three-dimensional scans of a leg and ankle-foot orthosis were incorporated into a link segment model where the ankle-foot orthosis joint axis could be misaligned with the anatomic ankle joint axis. The leg/ankle-foot orthosis interface was modeled as a network of nodes connected by springs to estimate interface pressure. Motion between the leg and ankle-foot orthosis was calculated as the ankle joint moved through a gait cycle. While the three-dimensional model corroborated predictions of the previously published two-dimensional model that misalignments in the anterior -posterior direction would result in greater relative motion compared to misalignments in the proximal -distal direction, it provided greater insight showing that misalignments have asymmetrical effects. The three-dimensional model has been incorporated into a freely available computer program to assist others in understanding the consequences of joint misalignments. Models and simulations can be used to gain insight into functioning of systems of interest. We have developed a three-dimensional model to assess the effect of ankle joint axis misalignments in ankle-foot orthoses. The model has been incorporated into a freely available computer program to assist understanding of trainees and others interested in orthotics. © The International Society for Prosthetics and Orthotics 2014.

Biomechanical Comparison of an Open vs Arthroscopic Approach for Lateral Ankle Instability.

PubMed

Drakos, Mark C; Behrens, Steve B; Paller, Dave; Murphy, Conor; DiGiovanni, Christopher W

2014-08-01

The current clinical standard for the surgical treatment of ankle instability remains the open modified Broström procedure. Modern advents in arthroscopic technology have allowed physicians to perform certain foot and ankle procedures arthroscopically as opposed to traditional open approaches. Twenty matched lower extremity cadaver specimens were obtained. Steinman pins were inserted into the tibia and talus with 6 sensors affixed to each pin. Specimens were placed in a Telos ankle stress apparatus in an anteroposterior and then lateral position, while a 1.7 N-m load was applied. For each of these tests, movement of the sensors was measured in 3 planes using the Optotrak Computer Navigation System. Changes in position were calculated and compared with the unloaded state. The anteriortalofibular ligament and the calcaneofibular ligament were thereafter sectioned from the fibula. The aforementioned measurements in the loaded and unloaded states were repeated on the specimens. The sectioned ligaments were then repaired using 2 corkscrew anchors. Ten specimens were repaired using a standard open Broström-type repair, while the matched pairs were repaired using an arthroscopic technique. Measurements were repeated and compared using a paired t test. There was a statistically significant difference between the sectioned state and the other 3 states (P < .05). There were no statistically significant differences between the intact state and either the open or arthroscopic state (P > .05). There were no significant differences between the open and arthroscopic repairs with respect to translation and total combined motion during the talar tilt test (P > .05). Statistically significant differences were demonstrated between the 2 methods in 3 specific axes of movement during talar tilt (P = .04). Biomechanically effective ankle stabilization may be amenable to a minimally invasive approach. A minimally invasive, arthroscopic approach can be considered for treating patients

[Ultrasound in complex of radiological studies in diagnosis of ankle joint medial aspect pathologies].

PubMed

Gurgenidze, T; Mizandari, M

2011-10-01

The aim of the research is to study sonosemiotics of ankle joint pathology by means of ultrasound in order to optimize the diagnostic process and improve the treatment. 130 patients (age ranges from 5 to 70 years) underwent the radiological study of ankle joint medial aspect. Pathology types: degenerative-dystrophic diseases - 39 (30%), inflammatory pathology - 21 (16.2%), traumatic injuries - 20 (15.2%), vascular pathologies - 26 (20%), neurogenic problems -7 (5.4%), soft tissue neoplasms - 5 (3.8%), congenital anomalies - 7 (5.4%) and vertebral pathology - 5 (4.0%). The diagnostic studies include: a) Ultrasound, performed on digital ultrasound system using high frequency (7.5-12.0 MHz) linear probe with Doppler capability (all patients); b) X-Ray filming in antero-posterior and lateral projections (6 patients- 4.5%); c) MRI - T1 and T2 weighted images in saggital and transverse planes 10 patients (10.0%) and d) CT - 2 patients (1.5%); To 2 (1.5%) patient biopsy has been performed. This study showed that ultrasound was successful in ankle joint medial aspect pathology diagnosis in 108 cases (84.0%); It was ineffective in osseous pathology definition. In final diagnosis of impingment syndrom MRI was required in 4 (3.6%) cases. It is concluded that ultrasound should be used as a Gold Standard in diagnosis of localized pain and swelling in the ankle joint.

Ottawa Ankle Rules and Subjective Surgeon Perception to Evaluate Radiograph Necessity Following Foot and Ankle Sprain

PubMed Central

Pires, RES; Pereira, AA; Abreu-e-Silva, GM; Labronici, PJ; Figueiredo, LB; Godoy-Santos, AL; Kfuri, M

2014-01-01

Background: Foot and ankle injuries are frequent in emergency departments. Although only a few patients with foot and ankle sprain present fractures and the fracture patterns are almost always simple, lack of fracture diagnosis can lead to poor functional outcomes. Aim: The present study aims to evaluate the reliability of the Ottawa ankle rules and the orthopedic surgeon subjective perception to assess foot and ankle fractures after sprains. Subjects and Methods: A cross-sectional study was conducted from July 2012 to December 2012. Ethical approval was granted. Two hundred seventy-four adult patients admitted to the emergency department with foot and/or ankle sprain were evaluated by an orthopedic surgeon who completed a questionnaire prior to radiographic assessment. The Ottawa ankle rules and subjective perception of foot and/or ankle fractures were evaluated on the questionnaire. Results: Thirteen percent (36/274) patients presented fracture. Orthopedic surgeon subjective analysis showed 55.6% sensitivity, 90.1% specificity, 46.5% positive predictive value and 92.9% negative predictive value. The general orthopedic surgeon opinion accuracy was 85.4%. The Ottawa ankle rules presented 97.2% sensitivity, 7.8% specificity, 13.9% positive predictive value, 95% negative predictive value and 19.9% accuracy respectively. Weight-bearing inability was the Ottawa ankle rule item that presented the highest reliability, 69.4% sensitivity, 61.6% specificity, 63.1% accuracy, 21.9% positive predictive value and 93% negative predictive value respectively. Conclusion: The Ottawa ankle rules showed high reliability for deciding when to take radiographs in foot and/or ankle sprains. Weight-bearing inability was the most important isolated item to predict fracture presence. Orthopedic surgeon subjective analysis to predict fracture possibility showed a high specificity rate, representing a confident method to exclude unnecessary radiographic exams. PMID:24971221

The ANKLE TRIAL (ANKLE treatment after injuries of the ankle ligaments): what is the benefit of external support devices in the functional treatment of acute ankle sprain? : a randomised controlled trial