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1

The association of patellofemoral joint morphology with chondromalacia patella: a quantitative MRI analysis.  

PubMed

The relationship of patellofemoral congruency with chondromalacia patellae (CP) was retrospectively evaluated. Lateral patellar tilt angle (LPTA), sulcus angle (SA), trochlear depth (TD), and patella angle (PA) were measured at 301 knee magnetic resonance images and compared between groups with and without CP. In the CP group, LPTA and TD were significantly low (P<.01), SA was high (P<.01), while PA showed no difference (P>.05). The parameters were also compared between groups with mild and severe CP, and no significant difference was found (P>.05). Our results demonstrate that patellar tilt and trochlear dysplasia are related to the presence but not the degree of CP. PMID:24651059

Tuna, Burcu Kaya; Semiz-Oysu, Asl?han; Pekar, Bilhan; Bukte, Yasar; Hayirlioglu, Alper

2014-01-01

2

Relation between isokinetic muscle strength and functional capacity in recreational athletes with chondromalacia patellae  

PubMed Central

Objectives: To investigate the effects of isokinetic exercise on pain and functional test scores of recreational athletes with chondromalacia patellae (CMP) and to examine the correlation between isokinetic parameters and functional tests or pain score. Methods: The functional ability of 30 recreational athletes with unilateral CMP was evaluated using six different tests. Pain scores were assessed during daily activities before and after the treatment protocol. Isokinetic exercise sessions were carried out at angular velocities of 60°/s (25–90° range of flexion) and 180°/s (full range). These sessions were repeated three times a week for six weeks. Results: Quadriceps and hamstring peak torque, total work, and endurance ratios had improved significantly after the treatment, as did the functional parameters and pain scores. There was a poor correlation between the extensor endurance ratio and one leg standing test. A moderate correlation between the visual analogue scale and the extensor endurance ratio or flexion endurance ratio was also found. Conclusions: The isokinetic exercise programme used in this study had a positive effect on muscle strength, pain score, and functional ability of knees with CMP. The improvement in the functional capacity did not correlate with the isokinetic parameters. PMID:14665581

Yildiz, Y; Aydin, T; Sekir, U; Cetin, C; Ors, F; Alp, K

2003-01-01

3

Evaluation of the Chondromalacia Patella Using a Microscopy Coil: Comparison of the Two-Dimensional Fast Spin Echo Techniques and the Three-Dimensional Fast Field Echo Techniques  

PubMed Central

Objective We wanted to compare the two-dimensional (2D) fast spin echo (FSE) techniques and the three-dimensional (3D) fast field echo techniques for the evaluation of the chondromalacia patella using a microscopy coil. Materials and Methods Twenty five patients who underwent total knee arthroplasty were included in this study. Preoperative MRI evaluation of the patella was performed using a microscopy coil (47 mm). The proton density-weighted fast spin echo images (PD), the fat-suppressed PD images (FS-PD), the intermediate weighted-fat suppressed fast spin echo images (iw-FS-FSE), the 3D balanced-fast field echo images (B-FFE), the 3D water selective cartilage scan (WATS-c) and the 3D water selective fluid scan (WATS-f) were obtained on a 1.5T MRI scanner. The patellar cartilage was evaluated in nine areas: the superior, middle and the inferior portions that were subdivided into the medial, central and lateral facets in a total of 215 areas. Employing the Noyes grading system, the MRI grade 0-I, II and III lesions were compared using the gross and microscopic findings. The sensitivity, specificity and accuracy were evaluated for each sequence. The significance of the differences for the individual sequences was calculated using the McNemar test. Results The gross and microscopic findings demonstrated 167 grade 0-I lesions, 40 grade II lesions and eight grade III lesions. Iw-FS-FSE had the highest accuracy (sensitivity/specificity/accuracy = 88%/98%/96%), followed by FS-PD (78%/98%/93%, respectively), PD (76%/98%/93%, respectively), B-FFE (71%/100%/93%, respectively), WATS-c (67%/100%/92%, respectively) and WATS-f (58%/99%/89%, respectively). There were statistically significant differences for the iw-FS-FSE and WATS-f and for the PD-FS and WATS-f (p < 0.01). Conclusion The iw-FS-FSE images obtained with a microscopy coil show best diagnostic performance among the 2D and 3D GRE images for evaluating the chondromalacia patella. PMID:21228943

Kim, Hyun-joo; Kang, Chang Ho; Ryu, Jeong Ah; Shin, Myung Jin; Cho, Kyung-Ja; Cho, Woo Shin

2011-01-01

4

Anterior Knee Pain (Chondromalacia Patellae).  

ERIC Educational Resources Information Center

This article presents a pragmatic approach to the definition, diagnosis, and management of anterior knee pain. Symptoms and treatment are described. Emphasis is on active involvement of the patient in the rehabilitation exercise program. (IAH)

Garrick, James G.

1989-01-01

5

Cement penetration after patella venting  

Microsoft Academic Search

There is a high rate of patellofemoral complications following total knee arthroplasty. Optimization of the cement–bone interface by venting and suction of the tibial plateau has been shown to improve cement penetration. Our study was designed to investigate if venting the patella prior to cementing improved cement penetration.Ten paired cadaver patellae were allocated prior to resurfacing to be vented or

Christopher W. Jones; Li-On Lam; Adam Butler; David J. Wood; William R. Walsh

2009-01-01

6

Habitual dislocation of patella: A review  

PubMed Central

Habitual dislocation of patella is a condition where the patella dislocates whenever the knee is flexed and spontaneously relocates with extension of the knee. It is also termed as obligatory dislocation as the patella dislocates completely with each flexion and extension cycle of the knee and the patient has no control over the patella dislocating as he or she moves the knee1. It usually presents after the child starts to walk, and is often well tolerated in children, if it is not painful. However it may present in childhood with dysfunction and instability. Very little literature is available on habitual dislocation of patella as most of the studies have combined cases of recurrent dislocation with habitual dislocation. Many different surgical techniques have been described in the literature for the treatment of habitual dislocation of patella. No single procedure is fully effective in the surgical treatment of habitual dislocation of patella and a combination of procedures is recommended.

Batra, Sumit; Arora, Sumit

2014-01-01

7

Femoral Nerve Palsy with Patella Fracture  

PubMed Central

Femoral neuropathy may be associated with various etiologies and can cause severe walking disability. We present the case of a 25-year-old woman who underwent surgical repair for a patella fracture and complained of lower extremity pain, paresthesia, and weakness postoperatively. Electromyography and magnetic resonance imaging (MRI) revealed partial peripheral neuropathy of the left femoral nerve associated with the patella fracture. To our knowledge, this is the first reported case of femoral neuropathy associated with a patella fracture. PMID:24369003

Lee, Sang Hyoung; Lee, Tong Joo; Woo, Min Su

2013-01-01

8

Cement penetration after patella venting.  

PubMed

There is a high rate of patellofemoral complications following total knee arthroplasty. Optimization of the cement-bone interface by venting and suction of the tibial plateau has been shown to improve cement penetration. Our study was designed to investigate if venting the patella prior to cementing improved cement penetration. Ten paired cadaver patellae were allocated prior to resurfacing to be vented or non-vented. Bone mineral density (BMD) was measured by DEXA scanning. In vented specimens, a 1.6 mm Kirschner wire was used to breach the anterior cortex at the center. Specimens were resurfaced with standard Profix instrumentation and Versabond bone cement (Smith and Nephew PLC, UK). Cement penetration was assessed from Faxitron and sectioned images by a digital image software package (ImageJ V1.38, NIH, USA). Wilcoxon rank sum test was used to assess the difference in cement penetration between groups. The relationship between BMD and cement penetration was analyzed by Pearson correlation coefficient. There was a strong negative correlation between peak BMD and cement penetration when analyzed independent of experimental grouping (r(2)=-0.812, p=0.004). Wilcoxon rank sum testing demonstrated no significant difference (rank sum statistic W=27, p=0.579) in cement penetration between vented (10.53%+/-4.66; mean+/-std dev) and non-vented patellae (11.51%+/-6.23; mean+/-std dev). Venting the patella using a Kirschner wire does not have a significant effect on the amount of cement penetration achieved in vitro using Profix instrumentation and Versabond cement. PMID:19010682

Jones, Christopher W; Lam, Li-On; Butler, Adam; Wood, David J; Walsh, William R

2009-01-01

9

A double patella-like condition secondary to synovial osteochondromatosis  

PubMed Central

To our knowledge, this is the first case of synovial osteochondromatosis in a patient presenting with a double patella-like condition. The true duplication of the patella, which is called double patella, is extremely rare. In our case, the operative and histopathological findings showed that the double patella-like condition was secondarily induced by synovial osteochondromatosis. Synovial osteochondromatosis should be considered as a differential diagnosis for congenital double patella. PMID:22943294

2012-01-01

10

Giant-cell tumor of the patella.  

PubMed

We report a 38-year old man with a giant-cell tumor in a rare site, the patella. Primary patellar neoplasms are highly unusual. According to a survey by the Bone and Soft Tissue Tumor Committee of the Japanese Orthopaedic Association, of more than 2,126 giant-cell tumors of bone reported since 1972, only 22 were primary patellar neoplasms. We present a case of this rare entity along with its clinical and radiographic features. The first clinical symptom was anterior knee pain. Though anterior knee pain has numerous and varied causes, it is necessary to consider patellar bone tumors in the differential diagnosis. PMID:22358142

Yoshida, Yukihiro; Kojima, Toshio; Taniguchi, Masashi; Osaka, Shunzo; Tokuhashi, Yasuaki

2012-01-01

11

Pain in the knee associated with osteoporosis of the patella.  

PubMed Central

Four patients, all of whom complained of pain in the knee, were found to have radiological evidence of osteoporosis particularly marked in the patella. In 3 a neurological lesion at the appropriate spinal segment was present, and the fourth patient, who was frankly hysterical, had an autonomic disturbance. If radiological porosis is isolated to the patella a distant cause such as nerve irritation should be sought. Images PMID:856068

Corbett, M; Colston, J R; Tucker, A K

1977-01-01

12

Tuberculosis of the patella imitating chronic knee synovitis.  

PubMed

Tuberculosis of patella is a rare occurrence with incidence of less than 0.15% in the literature. Owing to its rarity the diagnosis is usually missed. Here we present a case of tuberculosis of the patella, being treated as chronic synovitis elsewhere. An 11-year-old boy presented to us with chronic knee swelling and a draining sinus of 5 months duration. He was being treated with broad spectrum antibiotics and incision and drainage. Standard X-rays revealed a lytic area with surrounding coke such as sequestrum in patella. MRI was suggestive of osteomyelitis of the patella with soft tissue oedema. Diagnosis was confirmed on biopsy. The patient was managed by curettage and excision of the sinus tract along with antitubercular treatment. The patient responded well to antitubercular therapy and gained excellent functional range of movement. In today's era of potent antituberculous drugs and decreasing tuberculosis incidence the rare and unusual locations of tuberculosis such as patella should be borne in mind while dealing with chronic lesions of the knee especially in tubercular endemic areas. A timely diagnosis helps in regaining good range of motion and a satisfactory outcome. PMID:24810456

Prakash, Jatin; Vijay, Vipul

2014-01-01

13

Surgical treatment options for patella tendon rupture, Part I: Acute.  

PubMed

Patella tendon rupture is a debilitating injury. Prompt diagnosis and treatment is essential to prevent retraction of the patella with subsequent adhesions and quadriceps contractures. In a young patient with an acute rupture, primary repair usually is possible with various methods described to protect the repair. In acute injuries with inadequate tissue, augmentation with hamstring tendons or allograft generally is necessary. Because of the different types of rupture and the possibility for poor quality tissue, the surgeon should always be prepared to combine different techniques to obtain tthe best repair. Continuous passive motion generally can be initiated early with a secure repair. In patients with a patella tendon ruptured that is promptly diagnosed, securely repaired, and followed closely through their rehabilitation, good results can be expected. PMID:16119282

Greis, Patrick E; Holmstrom, Michael C; Lahav, Amit

2005-07-01

14

Surgical treatment options for patella tendon rupture, part II: chronic.  

PubMed

Patella tendon rupture is a debilitating injury that often occurs in the setting of preexisting tendon degeneration. Prompt diagnosis and treatment is essential to prevent retraction of the patella with subsequent adhesions and quadriceps contractures. In the setting of a chronic rupture, augmentation with hamstring tendons or allograft reconstruction generally is necessary. Patients who undergo delayed repair are at risk for a compromised result secondary to loss of full knee flexion and decreased quadriceps strength, although a functional extensor mechanism is likely to be reestablished. Overall the results of chronic repair are less satisfactory than the acute repair, but still provide an extensor mechanism for the patient and thus provide function. PMID:16119741

Greis, Patrick E; Lahav, Amit; Holmstrom, Michael C

2005-08-01

15

Patellar maltracking is prevalent among patellofemoral pain subjects with patella alta: an upright, weightbearing MRI study  

PubMed Central

The purpose of this study is to determine if patellar maltracking is more prevalent among patellofemoral (PF) pain subjects with patella alta compared to subjects with normal patella height. We imaged 37 PF pain and 15 pain free subjects in an open-configuration magnetic resonance imaging scanner while they stood in a weightbearing posture. We measured patella height using the Caton-Deschamps, Blackburne-Peel, Insall-Salvati, Modified Insall-Salvati, and Patellotrochlear indices, and classified the subjects into patella alta and normal patella height groups. We measured patella tilt and bisect offset from oblique-axial plane images, and classified the subjects into maltracking and normal tracking groups. Patellar maltracking was more prevalent among PF pain subjects with patella alta compared to PF pain subjects with normal patella height (two-tailed Fisher’s exact test, p < 0.050). Using the Caton-Deschamps index, 67% (8/12) of PF pain subjects with patella alta were maltrackers, whereas only 16% (4/25) of PF pain subjects with normal patella height were maltrackers. Patellofemoral pain subjects classified as maltrackers displayed a greater patella height compared to the pain free and PF pain subjects classified as normal trackers (two-tailed unpaired t-tests with Bonferroni correction, p < 0.017). This study adds to our understanding of PF pain in two ways - 1) we demonstrate that patellar maltracking is more prevalent in PF pain subjects with patella alta compared to subjects with normal patella height; and 2) we show greater patella height in PF pain subjects compared to pain free subjects using four indices commonly used in clinics. PMID:23165335

Pal, Saikat; Besier, Thor F.; Beaupre, Gary S.; Fredericson, Michael; Delp, Scott L.; Gold, Garry E.

2012-01-01

16

Fat-suppressed three-dimensional fast spoiled gradient-recalled echo imaging: a modified FS 3D SPGR technique for assessment of patellofemoral joint chondromalacia.  

PubMed

Fast fat-suppressed (FS) three-dimensional (3D) spoiled gradient-recalled echo (SPGR) imaging of 64 articular cartilage regions in 16 patellofemoral joints was evaluated to assess its feasibility in diagnosing patellofemoral chondromalacia. It demonstrated good correlation with arthroscopic reports and took about half of the examination time that FS 3D SPGR did. This modified, faster technique has the potential to diagnose patellofemoral chondromalacia with shorter examination time than FS 3D SPGR did. PMID:10506912

Wang, S F; Cheng, H C; Chang, C Y

1999-01-01

17

Distalization of the patella during tibial callus distraction.  

PubMed

Consecutive distalization of the patella is described in two patients undergoing segmental transportation after high tibial corticotomy. Revision surgery with loosening and proximal reattachment of a portion of the patellar ligament bridging the callus distraction zone could re-establish the correct patellar position. Despite excellent callus formation after tibial corticotomy just below the tibial tuberositas, this procedure should be performed more distally as the fibers of the patellar tendon spread laterally and distally. PMID:9709862

Eingartner, C; Bretschneider, C; Badke, A; Weise, K

1998-01-01

18

Management of the Deficient Patella in Revision Total Knee Arthroplasty  

Microsoft Academic Search

There are a number of options available to manage the patella when revising a failed total knee arthroplasty. If the previous\\u000a patellar component is well-fixed, undamaged, not worn, and compatible with the femoral revision component, then it can be\\u000a retained. When a patellar component necessitates revision and is removed with adequate remaining patellar bone stock, an onlay-type\\u000a all-polyethylene cemented implant

Ryan M. Garcia; Matthew J. Kraay; Patricia A. Conroy-Smith; Victor M. Goldberg

2008-01-01

19

Ossification in the patellar tendon and patella alta following sports injuries in children  

Microsoft Academic Search

Two patients with sleeve fractures of the patella and tibial tuberosity respectively are described. Our two cases demonstrate that the diagnosis can be difficult; patella alta and ossification in the patellar tendon are complications of conservative treatment. Early diagnosis and operative reduction and fixation are mandatory.

J. D. Bruijn; R. J. Sanders; B. R. H. Jansen

1993-01-01

20

Diagnosis and treatment of stress fracture of the patella in atheletes  

Microsoft Academic Search

Five cases of stress fracture of the patella in athletes are presented. Four of these occurred transversally in the lower part and one longitudinally in the lateral part of the patella. Three of the patients were females (endurance runner, high jumper, and orienteerer) and two males (volleyball and soccer player). The diagnosis was made 2–8 months from the onset of

S. Orava; S. Taimela; M. Kvist; J. Karpakka; A. Hulkko; U. Kujala

1996-01-01

21

Missing Creases of Distal Finger Joints as a Diagnostic Clue of Nail-Patella Syndrome  

Microsoft Academic Search

Nail-patella syndrome (NPS, OMIM 161200) is an autosomal dominant disorder with a clinical characteristic tetrad consisting of fingernail dysplasia, hypoplastic or absent patellae, bony protuberances of the ilia (iliac horns) and dislocation of the radial head. Kidney involvement may lead to renal failure, and there is an increased risk for glaucoma. Clinical diagnostic skin clues are triangular lunulae especially on

Peter H. Itin; Georg Eich; Susanna K. Fistarol

2006-01-01

22

The use of a tantalum-based Augmentation Patella in patients with a previous patellectomy  

Microsoft Academic Search

Patients with previous patellectomies for anterior knee pain syndrome, can remain symptomatic and develop osteoarthrosis or instability. We report our experience of the use of a novel implant to substitute for the absent native patella.Seven patients, with previous patellectomies, were treated with the Augmentation Patella (Zimmer, Allendale, USA). This implant was sutured to the patellar tendon, as part of a

Yune Kwong; Vikram V. Desai

2008-01-01

23

Stress fracture of the patella in a palmwine tapper.  

PubMed

Stress fracture of the patella in a twenty-nine-year-old palmwine tapper is reported. The fracture occurred during a busy tapping day which was his first working day after a ten-day sick off for a febrile illness and presentation was delayed for six weeks. Initial diagnosis was pathological fracture, but X-ray examination and histology of the biopsy from the fracture site did not suggest any associated disease. The pathomechanics of palmwine tapping is very similar to jumping (parachute) which is the usual cause of this fracture in developed countries. PMID:8470307

Oginni, L M

1993-03-01

24

An investigation of green iridescence on the mollusc Patella granatina  

NASA Astrophysics Data System (ADS)

In this paper we investigate the relatively rare phenomenon of iridescence on the outer surface of seashells (not the well known pearly inner surfaces). Using reflection spectroscopy and scanning electron microscopy we show that rows of iridescent green spots on the mollusc Patella granatina are caused by a thin-film stack buried about 100 µm below the rough outer surface of the shell. The high-density layers in the stack seem to be made of crystalline aragonite, but according to Raman spectroscopy and ellipsometry measurements the low-density layers as well as the bulk of the shell wall are a mixture of porous aragonite and organic materials such as carotenoids.

Brink, D. J.; van der Berg, N. G.

2005-01-01

25

Linkage analysis of the Nail-patella syndrome  

SciTech Connect

Nail-patella syndrome (NPS) is an autosomal dominant disorder characterized by dysplasia of nails and patella, decreased mobility of the elbow, iliac horns, and, in some cases, nephropathy. The disorder has been mapped to the long arm of chromosome 9, but the precise localization and identity of the NPS gene are unknown. Linkage analysis in three NPS families, using highly informative dinucleotide repeat polymorphisms on 9q33-q34, confirmed linkage of NPS to this chromosome. Recombinations were detected, by two-point linkage analysis, between NPS and the centromeric markers D9S60 and the gelsolin gene and the telomeric markers D9S64 and D9S66, in one of the families. Haplotype analysis suggested an additional recombination between NPS and the argininosuccinate synthetase (ASS) gene. These results localize the NPS gene to an interval on 9q34.1, distal to D9S60 an proximal to ASS, comprising a genetic distance of {approximately}9 cM. This represents a significant refinement in the localization of the NPS gene. 25 refs., 2 figs., 1 tab.

Campeau, E.; Watkins, D.; Rouleau, G.A. [Montreal General Hospital, Quebec (Canada); Babul, R.; Der Kaloustian, V.M. [McGill Univ., Montreal (Canada); Buchanan, J.A.; Meschino, W. [North York General Hospital (Canada)

1995-01-01

26

Early PROMs following total knee arthroplasty--functional outcome dependent on patella resurfacing.  

PubMed

Patella resurfacing during primary total knee arthroplasty (TKA) remains controversial. Variation in published results for patella resurfacing may potentially be explained by differences in design between TKA brands. We interrogated NJR-PROMs data to ascertain whether there is an early functional benefit to resurfacing the patella, both overall and for each of the five most popular primary knee designs through use of the Oxford Knee Score. A total of 8103 resurfaced TKAs and 15,290 nonresurfaced TKAs were studied. There was a large variation in the proportion of knees undergoing patella resurfacing by brand (Nexgen=16% versus Triathlon=52%). Patellar resurfacing did not significantly influence the magnitude of improvement in overall knee function or anterior knee-specific function irrespective of TKA brand or for cruciate retaining versus sacrificing designs. PMID:23769662

Baker, Paul N; Petheram, Timothy; Dowen, Daniel; Jameson, Simon S; Avery, Peter J; Reed, Mike R; Deehan, David J

2014-02-01

27

Percutaneous tension band wiring for minimally displaced fractures of the patella  

Microsoft Academic Search

Percutaneous tension band wiring was carried out on 26 minimally displaced transverse fractures of the patella. Plaster immobilisation was not necessary and knee movements were encourraged after the 5th day. Excellent function was regained in every case.

A. Biyani; N. C. Mathur; J. C. Sharma

1990-01-01

28

Elongated patellae at the final stage of Osgood–Schlatter disease: A radiographic study  

Microsoft Academic Search

Aetiology of Osgood–Schlatter disease (OSD) is still unknown. Relative length of the patellar articular surface with the length of the patella, relative height of the tibial tubercle with the sagittal diameter of the tibia, Insall–Salvati, Blackburne–Peel, and Caton–Deschamps indexes, as well as Grelsamer-morphology type of the patella were measured from preoperative plain X-rays in 82 knees of 20-year-old males with

T. Visuri; H. K. Pihlajamäki; V. M. Mattila; M. Kiuru

2007-01-01

29

Challenges in imaging and histopathological assessment of a giant cell tumour with secondary aneurysmal cyst in the patella.  

PubMed

The patella is an uncommon site for all primary and metastatic bone tumours and primary intra-osseous tumours of the patella are very rare. A majority of the patella tumours are benign. We report a patient with a sudden onset swelling and pain of the right knee following a staircase fall. The plain radiograph showed an expansile multiseptated patella lesion and it was further assessed with an MRI. The radiological findings and the initial histopathological features from a limited sample were suggestive of a primary aneurysmal bone cyst. However, the final histopathological diagnosis from a more adequate specimen was a giant cell tumour with a secondary aneurysmal bone cyst. PMID:24057334

Low, Soo Fin; Hanafiah, Mohammad; Nurismah, Md Isa; Suraya, Aziz

2013-01-01

30

Elongated patellae at the final stage of Osgood-Schlatter disease: a radiographic study.  

PubMed

Aetiology of Osgood-Schlatter disease (OSD) is still unknown. Relative length of the patellar articular surface with the length of the patella, relative height of the tibial tubercle with the sagittal diameter of the tibia, Insall-Salvati, Blackburne-Peel, and Caton-Deschamps indexes, as well as Grelsamer-morphology type of the patella were measured from preoperative plain X-rays in 82 knees of 20-year-old males with OSD and in 87 knees of 20-year-old male controls with normal MRI findings of the knee. Seventy-eight of the OSD patients had separate ossicles. Their mean patellar morphology index was 1.44 and that of the controls was 1.28 (p<0.001), indicating significant lengthening of the patellar body among the OSD group. OSD patients had also significantly more often Grelsamer type II (elongated patellae) than the controls. Tibial tuberosity was significantly higher among OSD patients, but was not correlated with the lengthening of the patella. An increased patellar height among OSD patients was shown by the Blackburne-Peel and Caton-Deschamps indexes (p<0.001) and the Insall-Salvati index (p=0.018). OSD patients exhibit elongated patellae and patellar tendons which may result from long-standing tension of the extensor apparatus during growth spurt, when femoral growth exceeds that of the anterior structures of the knee. PMID:17407814

Visuri, T; Pihlajamäki, H K; Mattila, V M; Kiuru, M

2007-06-01

31

Increased incidence of patella baja after total knee arthroplasty revision for infection.  

PubMed

The incidence of patella baja in total knee arthroplasty (TKA) revisions for aseptic and septic causes is not well defined. We retrospectively reviewed 101 mobile-bearing TKA revisions performed between 2003 and 2009. Aseptic (n = 67) and septic (n = 34) revisions were compared for patella baja. A nonarticulating spacer was used as the initial treatment for infected cases. The Insall-Salvati ratio was radiographically measured before surgery (preexplant for septic revisions) and at latest follow-up (postreplant for septic revisions). Mean (SD) Insall-Salvati ratio did not differ between groups before surgery, 1.00 (0.25) for aseptic and 0.96 (0.22) for septic, but differed significantly after surgery, 0.99 (0.23) for aseptic and 0.77 (0.24) for septic. After correcting for preoperative patellar height, there was a statistically significant postoperative difference between aseptic cases, 1.09 (0.19), and septic cases, 0.82 (0.21). There was also a significant difference in mean (SD) postoperative range of motion (ROM) between aseptic cases, 108.0° (20.7°), and septic cases, 92.2° (34.6°), and decreased ROM between cases with patella baja, 95.1° (31.6°) and cases without patella baja, 106.8° (23.6°). TKA revisions done for septic causes using a nonarticulating spacer resulted in a higher incidence of patella baja and decreased ROM. PMID:25490011

Chen, Antonia F; Tetreault, Matthew W; Levicoff, Eric A; Fedorka, Catherine J; Rothenberg, Adam C; Klatt, Brian A

2014-12-01

32

An Isolated Articular Surface Fracture of the Distal Patella: An Unusual and Previously Unreported Paediatric Injury  

PubMed Central

Paediatric patella fractures are uncommon, accounting for less than 1% of all paediatric fractures. This case report describes a previously undocumented patella fracture in a child, with a clear mechanism of injury. We present a case of a previously healthy 14-year-old boy who fell directly onto his right knee after coming off his pushbike. He sustained an isolated fracture involving the articular surface of the distal part of the patella with minimal displacement. The patient was managed conservatively in a Richard splint for three weeks, followed by a knee brace with gradually increasing degrees of flexion. He was instructed to be nonweight bearing for two weeks and then partial weight bearing for six weeks. At the final followup, after 9 weeks, the patient had full return of function and standard radiographs show the fracture to be healed. This case report has demonstrated how direct compression to the paediatric patella can cause a fracture isolated to its articular surface. It has detailed the natural progression of this injury to radiographic union, using a conservative management strategy. The authors believe that this case report provides an interesting insight into the variation of paediatric patella fractures and their contrasting management strategies. PMID:24383029

Shivji, Faiz S.; Ramoutar, Darryl N.; Hunter, James B.

2013-01-01

33

Hereditary onycho-osteodysplasia (nail-patella syndrome). A three-generation familial study.  

PubMed

Hereditary onycho-osteodysplasia or nail-patella syndrome is an uncommon familial musculoskeletal condition that is primarily seen initially in orthopaedic clinics. This three-generation familial review identifies three affected family members, one of whom demonstrated spondylolisthesis, a condition not previously associated with nail-patella syndrome. All affected family members demonstrated the typical radial nail dysplasias, hypoplastic patellae, iliac horns, and posterior dislocation of the radial heads. Overgrowth of the medial femoral condyles caused valgus deformities of the knees that necessitated orthotic treatment in the youngest affected family member. Although this syndrome has classic common musculoskeletal anomalies, the lumbar spine should also be carefully examined for the presence of spondylolysis and for signs of potential spondylolisthetic development. PMID:2023790

Letts, M

1991-03-01

34

Vertical Open Patella Fracture, Treatment, Rehabilitation and the Moment to Fixation  

PubMed Central

Patella fracture is relatively uncommon and the vertical trace fracture represents almost 12-17%. The open patella fracture expresses 6-30%. The association of these two uncommon conditions was the aim of this case report even as the treatment and the moment of fixation (definitive surgical treatment). A 27-year-old man after a motorcycle accident showed an open patella fracture classified as a Gustilo and Anderson type IIIA lesion. The patient was immediately treated with precocious surgery fixation with a modified tension band which consists of two parallel K-wires positioned orthogonal to the fracture line and a cerclage wire shaped anteriorly at patella as an eight. The premature fixation benefited the infection prevention and provided earlier joint motion, which increased the nutrition of articular cartilage. Six months postoperatively, the patient had a satisfactory joint motion with full extension and 116° of joint flexion and returned to his daily life activities without restriction. Twelve months postoperatively, the patient had full extension and 120° of knee flexion without pain, joint effusion and instability. Muscle strength force was considered normal at grade V. In conclusion, early chirurgic treatment and precocious articular mobilization improve prognosis, suggesting that the employment of these practices should be adopted whenever possible in most of the open fractures. PMID:25436033

Larangeira, Joao Alberto; Bellenzier, Liliane; Rigo, Vanessa da Silva; Ramos Neto, Elias Josue; Krum, Francisco Fritsch Machry; Ribeiro, Tiango Aguiar

2015-01-01

35

Incidence, mechanism of injury, and treatment of fractures of the patella in children.  

PubMed

Fractures of the patella in skeletally immature patients are rare. The charts of 185 patients treated for patella fractures at the University of Kentucky Medical Center between 1976 and 1988 were retrospectively reviewed. The 12 patients of these 185 aged 8 to 16 years were included in this study. The incidence was calculated to be 6.5% of all patella fractures. All patients studied were male with an average age of 12.7 years. Sleeve fractures were the most common type of patella fracture observed (five), followed by transverse fractures (four). Ten of the 12 cases required operative management ranging from irrigation and debridement to open reduction and internal fixation. Partial patellectomy was performed when indicated. Indications for operative management in this age group were similar to those for adults. As in adults, the mechanism of injury was predominantly motor vehicle and motorcycle crashes. Laws requiring seatbelt restraints for children should have a positive effect on the incidence of such fractures resulting from dashboard injuries. One mechanism of injury not reported previously was that of a flexed knee striking the gym wall after performing a basketball lay-up because the basket was placed flush with the wall. PMID:1569620

Ray, J M; Hendrix, J

1992-04-01

36

Vertical open patella fracture, treatment, rehabilitation and the moment to fixation.  

PubMed

Patella fracture is relatively uncommon and the vertical trace fracture represents almost 12-17%. The open patella fracture expresses 6-30%. The association of these two uncommon conditions was the aim of this case report even as the treatment and the moment of fixation (definitive surgical treatment). A 27-year-old man after a motorcycle accident showed an open patella fracture classified as a Gustilo and Anderson type IIIA lesion. The patient was immediately treated with precocious surgery fixation with a modified tension band which consists of two parallel K-wires positioned orthogonal to the fracture line and a cerclage wire shaped anteriorly at patella as an eight. The premature fixation benefited the infection prevention and provided earlier joint motion, which increased the nutrition of articular cartilage. Six months postoperatively, the patient had a satisfactory joint motion with full extension and 116° of joint flexion and returned to his daily life activities without restriction. Twelve months postoperatively, the patient had full extension and 120° of knee flexion without pain, joint effusion and instability. Muscle strength force was considered normal at grade V. In conclusion, early chirurgic treatment and precocious articular mobilization improve prognosis, suggesting that the employment of these practices should be adopted whenever possible in most of the open fractures. PMID:25436033

Larangeira, Joao Alberto; Bellenzier, Liliane; Rigo, Vanessa da Silva; Ramos Neto, Elias Josue; Krum, Francisco Fritsch Machry; Ribeiro, Tiango Aguiar

2015-02-01

37

Study of metals concentration levels in Patella piperata throughout the Canary Islands, Spain.  

PubMed

In order to assess the extent of metal contamination at rocky shores of the Canarian Archipelago, metal concentrations have been measured in Patella piperata (Gould, 1846), using the standard atomic absorption spectrophotometer technique. Ranges of elements concentrations measured (in microg g(-1)) found in the biota were: Cd (0.36 +/- 0.26 microg g(-1) dry wt.), Cu (2.05 +/- 0.91 dry wt.), Pb (1.57 +/- 1.14 microg g(-1)dry wt.) and Zn (10.37 +/- 4.60 microg g(-1) dry wt.). Variation in metal concentrations in Patella, was tested by using non-parametric statistical methods. Cd content had a maximum in the Archipelago Chinijo, northward of Lanzarote Island. The metal concentrations recorded at the clean stations may be considered carefully if they are used like background levels. PMID:17171292

Bergasa, Oscar; Ramírez, Rubén; Collado, Cayetano; Hernández-Brito, J Joaquín; Gelado-Caballero, María Dolores; Rodríguez-Somozas, María; Haroun, Ricardo J

2007-04-01

38

Giant cell tumor of the patella: An uncommon cause of anterior knee pain.  

PubMed

The patella is a rare site for the development of primary tumors. This is the case report of a giant cell tumor (GCT) occurring in the patella in a 25-year-old woman. The patient presented with a 1-year history of occasional right anterior knee pain. The radiological characteristics suggested a benign condition. The intraoperative pathological diagnosis was GCT of the bone. The lesion was treated by radical curettage with adjuvant therapy comprising phenol and ethanol and injection of calcium phosphate cement. Histologically, the tumor consisted of round or spindle-shaped mononuclear cells admixed with numerous osteoclastic giant cells. The patient was asymptomatic and there was no evidence of local recurrence or distant metastasis 16 months after surgery. Although rare, patellar GCT may be included in the differential diagnosis of anterior knee pain and/or swelling, particularly in young adults. PMID:25469296

Shibata, Tatsuya; Nishio, Jun; Matsunaga, Taiki; Aoki, Mikiko; Iwasaki, Hiroshi; Naito, Masatoshi

2015-01-01

39

Allozymic Differentiation Among Geographically Distant Populations of Patella vulgata (Mollusca, Patellogastropoda)  

Microsoft Academic Search

Patella vulgata is a boreal cold temperate species and is the dominant limpet in northern Europe. Few works have focussed on the population\\u000a genetics of this species. Therefore, the aim of this work was to assess the degree of genetic and morphological differentiation\\u000a of P. vulgata on a macroscale by using 20 allozyme loci and 6 morphological variables. Samples were

L. I. Weber; L. I. Hawkins

2006-01-01

40

Osteochondrosis of the superior pole of the patella: two cases with histologic correlation.  

PubMed

Two cases of osteochondrosis of the superior pole of the patella are reported with histologic findings. Both patients were young girls; one had mild cerebral palsy. Sixteen cases of this disorder have been documented but without histologic study. The histologic features of these two cases showed osteonecrosis with reparative changes. These findings support that this entity is similar to other osteochondroses of the quadriceps mechanism: Osgood-Schlatter disease and Sinding-Larsen-Johansson disease. PMID:12180619

Tyler, Wakenda; McCarthy, Edward F

2002-01-01

41

Isolation and characterisation of polymorphic microsatellite markers for the endangered ferreous limpet Patella ferruginea (Gastropoda, Patellidae)  

Microsoft Academic Search

The limpet Patella ferruginea is one of the most endangered marine invertebrates on western Mediterranean rocky shores. We have isolated and characterised\\u000a 11 polymorphic microsatellites markers to provide new tools to investigate genetic structure and gather information necessary\\u000a for the proper management of this severely threatened species. The number of alleles per locus ranged from 2 to 16 (mean;\\u000a Na = 8.37)

A. Machordom; U. Ramírez-Escobar; I. Acevedo; R. García-Jiménez; P. Cabezas; M. Calvo; C. Toledo; P. Bloor

2010-01-01

42

Metaphylogenomic and Potential Functionality of the Limpet Patella pellucida’s Gastrointestinal Tract Microbiome  

PubMed Central

This study investigated the microbial diversity associated with the digestive tract of the seaweed grazing marine limpet Patella pellucida. Using a modified indirect DNA extraction protocol and performing metagenomic profiling based on specific prokaryotic marker genes, the abundance of bacterial groups was identified from the analyzed metagenome. The members of three significantly abundant phyla of Proteobacteria, Firmicutes and Bacteroidetes were characterized through the literature and their predicted functions towards the host, as well as potential applications in the industrial environment assessed. PMID:25334059

Dudek, Magda; Adams, Jessica; Swain, Martin; Hegarty, Matthew; Huws, Sharon; Gallagher, Joe

2014-01-01

43

Does patella resurfacing really matter? Pain and function in 972 patients after primary total knee arthroplasty  

PubMed Central

Background and purpose Resurfacing of the patella during primary total knee arthroplasty (TKA) is often recommended based on higher revision rates in non-resurfaced knees. As many of these revisions are insertions of a patella component due to pain, and since only patients with a non-resurfaced patella have the option of secondary resurfacing, we do not really know whether these patients have more pain and poorer function. The main purpose of the present paper was therefore to assess pain and function at least 2 years after surgery for unrevised primary non-resurfaced and resurfaced TKA, and secondary among prosthesis brands. Methods Information needed to calculate subscales from the knee injury and osteoarthritis outcome score (KOOS) was collected in a questionnaire given to 972 osteoarthritis patients with intact primary TKAs that had been reported to the Norwegian Arthroplasty Register. Pain and satisfaction on visual analog scales and improvement in EQ-5D index score ?EQ-5D) were also used as outcomes. Outcomes were measured on a scale from 0 to 100 units (worst to best). To estimate differences in mean scores, we used multiple linear regression with adjustment for possible confounders. Results We did not observe any differences between resurfacing and non-resurfacing in any outcome, with estimated differences of ? 1.4 units and p-values of > 0.4. There was, however, a tendency of better results for the NexGen implant as compared to the reference brand AGC for symptoms (difference = 4.9, p = 0.05), pain (VAS) (difference = 8.3, p = 0.004), and satisfaction (VAS) (difference = 7.9, p = 0.02). However, none of these differences reached the stated level of minimal perceptible clinical difference. Interpretation Resurfacing of the patella has no clinical effect on pain and function after TKA. Differences between the brands investigated were small and they were assumed to be of minor importance. PMID:20158405

Espehaug, Birgitte; Havelin, Leif Ivar; Vollset, Stein Emil; Furnes, Ove

2010-01-01

44

Efficacy of various forms of fixation of transverse fractures of the patella.  

PubMed

To determine whether any of the commonly used wiring techniques are rigid enough to allow early motion in the treatment of transverse fracture of the patella, the patellae of twenty-five fresh cadaver knees were fractured transversely and fixed using the following techniques: circumferential wiring, tension-band wiring, Magnusson wiring, and a modification of tension-band wiring. The knees were mounted in a machine capable of measuring quadriceps force, flexion angle, and fracture separation simultaneously. The knees were extended from 90 to zero degrees by applying tension to the quadriceps tendon with the force of gravity as the only resistance, and separation of the fracture fragments was measured first with the retinaculum unrepaired and then again with the retinaculum repaired. Separation of the fracture fragments was much less with the Magnusson wiring and modified tension-band wiring than with circumferential wiring or standard tension-band wiring. The retinacular repair was found to contribute to stability; however, this seemed most important in the less rigid repairs. We concluded that if early motion is to be used in treating transverse fractures of the patella, techniques in which the wire is anchored directly in bone should be used and the retinaculum should be repaired. PMID:7358752

Weber, M J; Janecki, C J; McLeod, P; Nelson, C L; Thompson, J A

1980-03-01

45

Reconstruction of a deficient patella in revision total knee arthroplasty: results of a new surgical technique using transcortical wiring.  

PubMed

This study aimed to report the results of a novel surgical technique for the reconstruction of a deficient patella during revision total knee arthroplasty (TKA). Twenty-eight patients (30 knees) with a deficient patella were treated with an onlay-type prosthesis and bone-augmenting procedure, using acrylic bone cement and transcortical wiring. The technique was indicated when the thickness of remnant patella was less than 8mm with variable amounts of the peripheral rim. Mean follow-up period was 36.6months (range, 24 to 55months).The respective mean Knee Society scores for knee and function improved from 34.2 and 23 points, preoperatively to 73.5 and 61 points, at final follow-up. One patient experienced patellar fracture 1week after surgery. There were no complications associated with implanted hardware. PMID:25306111

Seo, Jai-Gon; Moon, Young-Wan; Lee, Byung-Hoon; Kim, Sang-Min

2015-02-01

46

3-D printouts of the tracheobronchial tree generated from CT images as an aid to management in a case of tracheobronchial chondromalacia caused by relapsing polychondritis.  

PubMed

This report concerns a 67 year old male patient with known advanced relapsing polychondritis complicated by tracheobronchial chondromalacia who is increasingly symptomatic and therapeutic options such as tracheostomy and stenting procedures are being considered. The DICOM files from the patient's dynamic chest CT in its inspiratory and expiratory phases were used to generate stereolithography (STL) files and hence print out 3-D models of the patient's trachea and central airways. The 4 full-sized models allowed better understanding of the extent and location of any stenosis or malacic change and should aid any planned future stenting procedures. The future possibility of using the models as scaffolding to generate a new cartilaginous upper airway using regenerative medical techniques is also discussed. PMID:24421951

Tam, Matthew David; Laycock, Stephen David; Jayne, David; Babar, Judith; Noble, Brendon

2013-08-01

47

3-D printouts of the tracheobronchial tree generated from CT images as an aid to management in a case of tracheobronchial chondromalacia caused by relapsing polychondritis  

PubMed Central

This report concerns a 67 year old male patient with known advanced relapsing polychondritis complicated by tracheobronchial chondromalacia who is increasingly symptomatic and therapeutic options such as tracheostomy and stenting procedures are being considered. The DICOM files from the patient’s dynamic chest CT in its inspiratory and expiratory phases were used to generate stereolithography (STL) files and hence print out 3-D models of the patient’s trachea and central airways. The 4 full-sized models allowed better understanding of the extent and location of any stenosis or malacic change and should aid any planned future stenting procedures. The future possibility of using the models as scaffolding to generate a new cartilaginous upper airway using regenerative medical techniques is also discussed. PMID:24421951

Tam, Matthew David; Laycock, Stephen David; Jayne, David; Babar, Judith; Noble, Brendon

2013-01-01

48

Mutation analysis of LMX1B gene in nail-patella syndrome patients.  

PubMed Central

Nail-patella syndrome (NPS), a pleiotropic disorder exhibiting autosomal dominant inheritance, has been studied for >100 years. Recent evidence shows that NPS is the result of mutations in the LIM-homeodomain gene LMX1B. To determine whether specific LMX1B mutations are associated with different aspects of the NPS phenotype, we screened a cohort of 41 NPS families for LMX1B mutations. A total of 25 mutations were identified in 37 families. The nature of the mutations supports the hypothesis that NPS is the result of haploinsufficiency for LMX1B. There was no evidence of correlation between aspects of the NPS phenotype and specific mutations. PMID:9837817

McIntosh, I; Dreyer, S D; Clough, M V; Dunston, J A; Eyaid, W; Roig, C M; Montgomery, T; Ala-Mello, S; Kaitila, I; Winterpacht, A; Zabel, B; Frydman, M; Cole, W G; Francomano, C A; Lee, B

1998-01-01

49

Plateau-patella angle in evaluation of patellar height after total knee arthroplasty.  

PubMed

The plateau-patella angle (PPA) has been proposed as a new and simpler method to describe patellar height. This method has not been used or validated in knees following total knee arthroplasty (TKA). A modified PPA (mPPA) was developed for use in this population. The method was validated by determining the interobserver and intraobserver reliability of the technique in 50 consecutive patients compared to three well-described methods of describing patellar height after TKA. Three observers then evaluated the mPPA of 297 post-operative radiographs to describe a normal range after TKA for a given technique and implant. The interobserver reliability was the highest for the mPPA compared to the other methods. The mean mPPA for the entire cohort was 21.06, 20.49, and 19.94 for the three observers. The modified plateau-patella angle is a reliable way to evaluate patellar height in patients who have undergone total knee arthroplasty. PMID:24612739

Robin, Brett N; Ellington, Matthew D; Jupiter, Daniel C; Allen, Bryce C

2014-07-01

50

Host Control of Symbiont Natural Product Chemistry in Cryptic Populations of the Tunicate Lissoclinum patella  

PubMed Central

Natural products (secondary metabolites) found in marine invertebrates are often thought to be produced by resident symbiotic bacteria, and these products appear to play a major role in the symbiotic interaction of bacteria and their hosts. In these animals, there is extensive variation, both in chemistry and in the symbiotic bacteria that produce them. Here, we sought to answer the question of what factors underlie chemical variation in the ocean. As a model, we investigated the colonial tunicate Lissoclinum patella because of its rich and varied chemistry and its broad geographic range. We sequenced mitochondrial cytochrome c oxidase 1 (COXI) genes, and found that animals classified as L. patella fall into three phylogenetic groups that may encompass several cryptic species. The presence of individual natural products followed the phylogenetic relationship of the host animals, even though the compounds are produced by symbiotic bacteria that do not follow host phylogeny. In sum, we show that cryptic populations of animals underlie the observed chemical diversity, suggesting that the host controls selection for particular secondary metabolite pathways. These results imply novel approaches to obtain chemical diversity from the oceans, and also demonstrate that the diversity of marine natural products may be greatly impacted by cryptic local extinctions. PMID:24788869

Kwan, Jason C.; Tianero, Ma. Diarey B.; Donia, Mohamed S.; Wyche, Thomas P.; Bugni, Tim S.; Schmidt, Eric W.

2014-01-01

51

Coccidiomycosis infection of the patella mimicking a neoplasm – two case reports  

PubMed Central

Background Coccidioidomycosis is an endemic fungal infection in the southwestern of United States. Most infections are asymptomatic or manifest with mild respiratory complaints. Rare cases may cause extrapulmonary or disseminated disease. We report two cases of knee involvement that presented as isolated lytic lesions of the patella mimicking neoplasms. Case Presentation The first case, a 27 year-old immunocompetent male had progressive left anterior knee pain for four months. The second case was a 78 year-old male had left anterior knee pain for three months. Both of them had visited general physicians without conclusive diagnosis. A low attenuation lytic lesion in the patella was demonstrated on their image studies, and the initial radiologist’s interpretation was suggestive of a primary bony neoplasm. The patients were referred for orthopaedic oncology consultation. The first case had a past episode of pulmonary coccioidomycosis 2 years prior, while the second case had no previous coccioidal infection history but lived in an endemic area, the central valley of California. Surgical biopsy was performed in both cases due to diagnostic uncertainty. Final pathologic examination revealed large thick walled spherules filled with endospores establishing the final diagnosis of extrapulmonary coccidioidomycosis. Conclusions Though history and laboratory findings are supportive, definitive diagnosis still depends on growth in culture or endospores identified on histology. We suggest that orthopaedic surgeons and radiologists keep in mind that chronic fungal infections can mimic osseous neoplasm by imaging. PMID:24548622

2014-01-01

52

Patellar Shape-Memory Fixator for the Treatment of Comminuted Fractures of the Inferior Pole of the Patella  

NASA Astrophysics Data System (ADS)

Comminuted and displaced fractures of the inferior pole of the patella are not easy to reduce and it is difficult to fix the fragments soundly enough to allow early movement of the knee. The purpose of this study is to evaluate the clinical effectiveness of the internal fixation technique with Patellar Shape-Memory Fixator (PSMF) in acute comminuted fractures of the inferior pole of the patella. We retrospectively studied 25 patients with comminuted fractures of the inferior pole of the patella who were treated with PSMF and followed up for a mean period of 26 months (14 to 60). All the fractures healed at a mean of 6 weeks (5 to 7). The mean grading at the final follow-up was 29.5 points (27 to 30) using the Bostman score, with no observable restriction of movement. No breakage of the PSMF or infection occurred. No delayed union, nonunion, and infection were seen. This technique preserved the length of the patella, reduced the comminuted fragments of the inferior pole and avoided long-term immobilization of the knee.

Liu, Xin-Wei; Shang, Hui-Juan; Xu, Shuo-Gui; Wang, Zhi-Wei; Zhang, Chun-Cai; Fu, Qing-Ge

2011-07-01

53

Trabecular Metal Patella Implanted into Soft-Tissue in a Post-Patellectomized Knee A Case Report  

Microsoft Academic Search

Clinical performance and microscopic analysis of a porous tantalum patella, retrieved from a 34-year-old male patient eight months after implantation is reported. The patellar component was sectioned and microscopically analyzed to determine the extent and characteristics of the soft tissue ingrowth. The metallic tantalum represented 20 vol.% of the analyzed patellar component. Large and small spherical pores were identified. Only

D. Gordon Allan; Manish Paliwal; Peter Filip

2007-01-01

54

Food supply, grazing activity and growth rate in the limpet Patella vulgata L.: a comparison between exposed and sheltered shores  

Microsoft Academic Search

The limpet Patella vulgata L. is an important microphagous grazer on intertidal rocky shores of north-west Europe, occurring across the wave exposure gradient. Groups of P. vulgata were selected at mid-tide level of two exposed shores and two sheltered, fucoid dominated shores on the Isle of Man, British Isles, and manipulated to equivalent densities and population structure. The level of

Stuart R. Jenkins; Richard G. Hartnoll

2001-01-01

55

[Nail-patella syndrome associated with monoclonal gammopathy. Review regarding a case].  

PubMed

A 54 years old female with significant impairment of renal function is presented. On physical examination, the presence of dystrophic nails, elbow dysplasia and prominent iliac horns. Familial study showed similar nail and bone deformities in 3 of six sons. The nail patella syndrome diagnosis was based on these findings. This is a rare autosomal dominant hereditary disease, probably related to congenital alterations in collagen metabolism. Clinical characteristics include bone abnormalities that principally involve knees and elbows, nail alterations and the presence of iliac horns, that are considered pathognomonic of the syndrome. Renal involvement is observed in 30 to 55% of cases. This patient had also an IgA-lambda paraprotein, whose relationship to the above mentioned syndrome is uncertain, since no evidences of malignant plasma cell dyscrasia were demonstrated. PMID:8235167

Panace, R; Mocarquer, A; Anguita, T; Cortés, H

1993-01-01

56

Microbial diversity of biofilm communities in microniches associated with the didemnid ascidian Lissoclinum patella  

PubMed Central

We assessed the microbial diversity and microenvironmental niche characteristics in the didemnid ascidian Lissoclinum patella using 16S rRNA gene sequencing, microsensor and imaging techniques. L. patella harbors three distinct microbial communities spatially separated by few millimeters of tunic tissue: (i) a biofilm on its upper surface exposed to high irradiance and O2 levels, (ii) a cloacal cavity dominated by the prochlorophyte Prochloron spp. characterized by strong depletion of visible light and a dynamic chemical microenvironment ranging from hyperoxia in light to anoxia in darkness and (iii) a biofilm covering the underside of the animal, where light is depleted of visible wavelengths and enriched in near-infrared radiation (NIR). Variable chlorophyll fluorescence imaging demonstrated photosynthetic activity, and hyperspectral imaging revealed a diversity of photopigments in all microhabitats. Amplicon sequencing revealed the dominance of cyanobacteria in all three layers. Sequences representing the chlorophyll d containing cyanobacterium Acaryochloris marina and anoxygenic phototrophs were abundant on the underside of the ascidian in shallow waters but declined in deeper waters. This depth dependency was supported by a negative correlation between A. marina abundance and collection depth, explained by the increased attenuation of NIR as a function of water depth. The combination of microenvironmental analysis and fine-scale sampling techniques used in this investigation gives valuable first insights into the distribution, abundance and diversity of bacterial communities associated with tropical ascidians. In particular, we show that microenvironments and microbial diversity can vary significantly over scales of a few millimeters in such habitats; which is information easily lost by bulk sampling. PMID:22134643

Behrendt, Lars; Larkum, Anthony W D; Trampe, Erik; Norman, Anders; Sørensen, Søren J; Kühl, Michael

2012-01-01

57

On the Role of the Patella, ACL and Joint Contact Forces in the Extension of the Knee  

PubMed Central

Traditional descriptions of the knee suggest that the function of the patella is to facilitate knee extension by increasing the moment arm of the quadriceps muscles. Through modelling and evidence from the literature it is shown in this paper that the presence of the patella makes the ability of the quadriceps to rotate the thigh greater than their ability to rotate the tibia. Furthermore, this difference increases as the knee is flexed, thus demonstrating a pattern that is consistent with many human movements. This paper also shows that the anterior cruciate ligament plays a previously unheralded role in extending the shank and that translation at the tibiofemoral and patellofemoral joints is important in improving the capacity for thigh rotation when the knee is flexed. This study provides new insights as to how the structure of the knee is adapted to its purpose and illustrates how the functional anatomy of the knee contributes to its extension function. PMID:25536067

Cleather, Daniel J.; Southgate, Dominic F. L.; Bull, Anthony M. J.

2014-01-01

58

Localization of a gene for familial patella aplasia-hypoplasia (PTLAH) to chromosome 17q21-22.  

PubMed Central

Patella aplasia-hypoplasia (PTLAH) is a rare genetic defect characterized by congenital absence or marked reduction of the patella. PTLAH can occur either as an isolated defect or in association with other malformations, and it characteristically occurs in the nail-patella syndrome and in some chromosome imbalances. We report the first evidence of linkage for isolated PTLAH in an extended Venezuelan family. After exclusion of the candidate chromosome regions where disorders associated with PTLAH have been mapped, a genomewide scan was performed that supported mapping of the disease locus within a region of 12 cM on chromosome 17q22. Two marker loci (D17S787 and D17S1604) typed from this region gave maximum LOD scores >3. Accordingly, multipoint analysis gave a maximum LOD score of 3.39, with a most likely location for the disease gene between D17S787 and D17S1604. Sequencing of the noggin gene, a candidate mapping between these markers, failed to reveal any mutation in affected subjects. PMID:10417287

Mangino, M; Sanchez, O; Torrente, I; De Luca, A; Capon, F; Novelli, G; Dallapiccola, B

1999-01-01

59

Minor and trace elements in the shell of Patella aspera (Röding 1798).  

PubMed

Specimens of the limpet Patella aspera were collected from a clean, coastal marine site and a contaminated estuary on the south coast of Portugal. The shells were analysed individually for their minor (Mg, Sr) and trace element (Fe, Mn, Zn) content. Mean concentrations of these elements in the shell of P. aspera were 4651, 1318, 35.8, 29.9 and 5.5 microg g(-1), respectively. The elemental concentrations exhibited both a marked intra- and inter-population variability. Despite the variability within individual populations, significant differences in the trace element composition were apparent between the shells taken from the two sites. Small shells (< 2 g) provided the best resolution between sites for both manganese and iron. Differences in zinc were best resolved for larger shells. The shell of P. aspera has an extraordinarily high magnesium concentration, which is insensitive to gross salinity differences, and a trace metal assemblage that can be interpreted in terms of environmental exposure. On these grounds, it is recommended that the shell of P. aspera is a tissue for potential use in environmental trace metal monitoring. PMID:12220116

Cravo, A; Foster, P; Bebianno, M J

2002-09-01

60

A Viscoelastic Constitutive Model Can Accurately Represent Entire Creep Indentation Tests of Human Patella Cartilage  

PubMed Central

Cartilage material properties provide important insights into joint health, and cartilage material models are used in whole-joint finite element models. Although the biphasic model representing experimental creep indentation tests is commonly used to characterize cartilage, cartilage short-term response to loading is generally not characterized using the biphasic model. The purpose of this study was to determine the short-term and equilibrium material properties of human patella cartilage using a viscoelastic model representation of creep indentation tests. We performed 24 experimental creep indentation tests from 14 human patellar specimens ranging in age from 20 to 90 years (median age 61 years). We used a finite element model to reproduce the experimental tests and determined cartilage material properties from viscoelastic and biphasic representations of cartilage. The viscoelastic model consistently provided excellent representation of the short-term and equilibrium creep displacements. We determined initial elastic modulus, equilibrium elastic modulus, and equilibrium Poisson’s ratio using the viscoelastic model. The viscoelastic model can represent the short-term and equilibrium response of cartilage and may easily be implemented in whole-joint finite element models. PMID:23027200

Pal, Saikat; Lindsey, Derek P.; Besier, Thor F.; Beaupre, Gary S.

2013-01-01

61

The Middle Miocene Ape Pierolapithecus catalaunicus Exhibits Extant Great Ape-Like Morphometric Affinities on Its Patella: Inferences on Knee Function and Evolution  

PubMed Central

The mosaic nature of the Miocene ape postcranium hinders the reconstruction of the positional behavior and locomotion of these taxa based on isolated elements only. The fossil great ape Pierolapithecus catalaunicus (IPS 21350 skeleton; 11.9 Ma) exhibits a relatively wide and shallow thorax with moderate hand length and phalangeal curvature, dorsally-oriented metacarpophalangeal joints, and loss of ulnocarpal articulation. This evidence reveals enhanced orthograde postures without modern ape-like below-branch suspensory adaptations. Therefore, it has been proposed that natural selection enhanced vertical climbing (and not suspension per se) in Pierolapithecus catalaunicus. Although limb long bones are not available for this species, its patella (IPS 21350.37) can potentially provide insights into its knee function and thus on the complexity of its total morphological pattern. Here we provide a detailed description and morphometric analyses of IPS 21350.37, which are based on four external dimensions intended to capture the overall patellar shape. Our results reveal that the patella of Pierolapithecus is similar to that of extant great apes: proximodistally short, mediolaterally broad and anteroposteriorly thin. Previous biomechanical studies of the anthropoid knee based on the same measurements proposed that the modern great ape patella reflects a mobile knee joint while the long, narrow and thick patella of platyrrhine and especially cercopithecoid monkeys would increase the quadriceps moment arm in knee extension during walking, galloping, climbing and leaping. The patella of Pierolapithecus differs not only from that of monkeys and hylobatids, but also from that of basal hominoids (e.g., Proconsul and Nacholapithecus), which display slightly thinner patellae than extant great apes (the previously-inferred plesiomorphic hominoid condition). If patellar shape in Pierolapithecus is related to modern great ape-like knee function, our results suggest that increased knee mobility might have originally evolved in relation to enhanced climbing capabilities in great apes (such as specialized vertical climbing). PMID:24637777

Pina, Marta; Almécija, Sergio; Alba, David M.; O'Neill, Matthew C.; Moyà-Solà, Salvador

2014-01-01

62

Indentation response of human patella with elastic modulus correlation to localized fractal dimension and bone mineral density.  

PubMed

The goal of this study was to determine material properties for the anterior cortex and subcortical regions of human patellae and relate those properties to mineral density and fractal dimension of the bone. Ten human patellae were obtained from eight fresh frozen human cadavers and subjected to anteriorly-directed spherical indentation-relaxation experiments using two different sized indenters to two different indentation depths. Response data were fit to a three-mode viscoelastic model obtained through elastic-viscoelastic correspondence of the Hertzian contact relation for spherical indentation. A location-specific effective bone density measurement that more heavily weighted bone material close to the indentation site (by von Mises stress distribution) was determined from micro-computed tomography (38µm resolution) data captured for each specimen. The same imagery data were used to compute location specific fractal dimension estimates for each indentation site. Individual and averaged patella material models verified the hypothesis that when the larger indenter and greater indentation depth is used to engage the surface and deeper (trabecular) bone, the bone exhibits a more compliant response than when only the surface (cortical) bone was engaged (instantaneous elastic modulus was 325MPa vs. 207MPa, p<0.05). Effective bone mineral density was shown to be a significant predictor of the elastic modulus for both small and large indentation types (p<0.05) despite relatively low correlations. Exponential regressions of fractal dimension on elastic modulus showed significant relationships with high correlation for both the small (R(2)=0.93) and large (R(2)=0.97) indentations. PMID:23972564

Kerrigan, Jason R; Sanchez-Molina, David; Neggers, Jan; Arregui-Dalmases, Carlos; Velazquez-Ameijide, Juan; Crandall, Jeff R

2014-05-01

63

Quantification of midkine gene expression in Patella caerulea (Mollusca, Gastropoda) exposed to cadmium  

NASA Astrophysics Data System (ADS)

The release of cadmium into many coastal areas represents a threat to ecosystems and human health; cadmium is carcinogenic in mammals and in both marine invertebrates and vertebrates. The use of molluscs to assess the ecologic risk associated with contaminants is strongly recommended on account of their ecological role and on their highly conserved control and regulatory pathways that are often homologous to vertebrate systems. We previously identified a midkine family protein in the limpet Patella caerulea; the midkine is a recently discovered cytokines family with unequivocal informative value on repairing injury and neoplastic processes in mammals. Here we report on midkine ( mdk) and ?-tubulin ( ?-tub) gene expression patterns in P. caerulea exposed to cadmium. Limpets, collected on two occasions from a breakwater at a marina (Tyrrhenian Sea) were exposed to sublethal cadmium concentrations (0.5 and 1 mg l -1 Cd) over a 10-day exposure period. RNA was extracted from the viscera of unexposed and exposed specimens. Real time TaqMan RT-PCR was performed to measure the relative mdk and ?-tub gene expression levels. A remarkable mdk over-expression was observed in all exposed animals with respect to unexposed ones; mdk over-expression was significantly higher in both treatments when compared with un-treatment (mean expression levels: 23- and 38-fold, for 0.5 and 1 mg l -1 Cd treatment, respectively; ANOVA, for both P < 0.01). The study also indicates that the mdk up-regulation was significantly Cd-concentration dependent ( P < 0.05). A significant up-regulation of the constitutive ?-tub gene was also observed in 1 mg l -1 Cd-treated animals (mean expression level: 4-fold; ANOVA, P < 0.05). In conclusion, these data provide the first evidence paving the way for the use of the midkine as a promising new biomarker of effect in the environment risk assessment policy.

Stillitano, Francesca; Mugelli, Alessandro; Cerbai, Elisabetta; Vanucci, Silvana

2007-10-01

64

A novel SOX9 H169Q mutation in a family with overlapping phenotype of mild campomelic dysplasia and small patella syndrome.  

PubMed

The phenotypic similarities have been demonstrated between non-lethal campomelic dysplasia (CD) and small patella syndrome (SPS), in which different genetic defects have been identified. We report on a familial case of skeletal dysplasia with overlapping phenotype of mild CD and SPS, including defective ischio-pubic ossification, elongated femoral neck, hypoplastic patellae, and increased space between the first and the second toes (sandal gap). Direct sequencing analysis demonstrated a novel missense mutation (p.H169Q) within the coding region of the SOX9 gene and negative for TBX4 mutations. Functional analysis of the p.H169Q mutant revealed reduced but not fully abolished transactivation capacity of the mutated protein. Retained residual SOX9 function might contribute to an extremely mild CD phenotype in the present cases. © 2013 Wiley Periodicals, Inc. PMID:24038782

Matsushita, Masaki; Kitoh, Hiroshi; Kaneko, Hiroshi; Mishima, Kenichi; Kadono, Izumi; Ishiguro, Naoki; Nishimura, Gen

2013-10-01

65

Mental retardation, premature balding, small genitalia, small acra and small patellae in brothers: confirmation of an entity.  

PubMed

We describe two brothers with moderate to severe mental retardation, short stature, an unusual skull shape, early anterior balding, unusual facial morphology, hypogonadotrophic hypogonadism, small genitalia, and small patellae. The older sib had generalized hypotonia without focal neurological abnormalities or myotonia. His brother had epileptic fits in infancy and tonic-clonic seizures from 5 years on, and died at 8 years of age during a seizure with possibly an intra-cerebral haemorrhage. Both brothers had a very similar face characterized by a high anterior hair line, small and upslanting palpebral fissures, deeply set eyes, a broad nasal tip, and everted lower lip. Additional studies in the older sib included a CGH array, and molecular testing of PQBP1 and FRAXA, all with normal results. Investigations of maternal lymphocytes showed completely skewed X-inactivation. The phenotype in the sibs resembles the phenotype reported in three unrelated patients reported by Scholte et al. in 1991 (MIM %181515) and Fryns et al. in 1993, and confirms this to be a clinically distinct entity. As all reported cases have been males, including two brothers, none of the parents were consanguineous, cytogenetic studies failed to show abnormalities, and X-inactivation was completely skewed in one of the mothers, we suggest this entity to follow an X-linked recessive pattern of inheritance. PMID:20624501

Vandersteen, Anthony M; Hennekam, Raoul C

2010-01-01

66

Spatial diversity of rocky midlittoral macro-invertebrates associated with the endangered species Patella ferruginea (Mollusca: Gastropoda) of Tunisian coastline  

NASA Astrophysics Data System (ADS)

The present study focuses on horizontal spatial variability of benthic macrofauna associated with Patella ferruginea. Thirty-six samples collected at 12 transects belonging to 4 midlittoral sites along the rocky Tunisian coastline, were examined. A total of 44 species belonging to 5 taxa were found. Multivariate analysis applied on gathered data did not show a horizontal spatial variability at small scale (between transects), but at large scale, between sites as well as sectors. Thus, three groups of communities were identified (GI: Korbous and El Haouaria; GIIa: Zembra Island and GIIb: Kelibia). The distribution of species abundance within these groups revealed that crustaceans were the most abundant taxon, due to the overwhelming dominance of Chthamalus stellatus. This substratum appeared to create favourable micro-habitats for the installation of molluscs including gastropods. Regarding the low diversity index ( H') and evenness ( J), they seemed to reflect a disturbance and a demographic unbalance within these communities. The heterogeneity of substrate surface, created by C. stellatus specimens appeared to be caused by various complex interactions established between the key components of these communities in particular suspension feeders, predators, herbivorous molluscs and macroalgae. Thus, the dynamic status of each of these communities is the result of these complex interactions.

Tlig-Zouari, Sabiha; Rabaoui, Lotfi; Fguiri, Hosni; Diawara, Moctar; Ben Hassine, Oum Kalthoum

2010-04-01

67

Paleoclimate of the Neoglacial and Roman Warm Period Reconstructed from Oxygen Isotope Ratios of Limpet Shells (Patella vulgata), Northwest Scotland  

NASA Astrophysics Data System (ADS)

Paleoclimate reconstructions from different regions have reported abrupt climate change around 2800-2700 cal yr B.P. The timing of this abrupt climate change is close to the boundary between the Neoglacial (3300-2500 cal yr B.P.) and Roman Warm Period (2500-1600 cal yr B.P.). However, temporal and spatial variability observed in this climate change event raises controversies about the forcing factors driving it and why it has regional variability. Scotland lies in the North Atlantic Ocean, which responds sensitively to climate change. Therefore, even in the case of subtle climate change, the climate variability of Scotland should be able to capture such change. In this study, we expect that paleoclimate reconstructions of the Neoglacial and Roman Warm Period in Scotland will help improve our knowledge of abrupt climate change at 2800-2700 cal yr B.P. Archaeological shell deposits provide a rich source of climate proxy data preserved as oxygen isotope ratios in shell carbonate. Croig Cave on the Isle of Mull, Scotland, contains a nearly continuous accumulation of shells ranging from 800 BC-500 AD and possibly older. This range represents a broad chronology of human use from the late Bronze to Iron Ages and spans the Neoglacial through Roman Warm Period climate episodes. Here, we present seasonal temperature variability of the two climate episodes based on oxygen isotope ratios of ten limpet shells (Patella vulgata) from Croig Cave. Based on AMS dating (2 sigma calibration), the oldest shell was from 3480-3330 cal yr B.P. and the youngest shell was from 2060-1870 cal yr B.P. Our results indicated that estimated temperatures from the Neoglacial limpets average 6.44±0.56°C for coldest winters and 15.06±0.67°C for warmest summers. For the Roman Warm Period limpets, the average is 5.68±0.36°C for coldest winters and 14.14±0.81°C for warmest summers. We compared our estimated temperatures to the present sea surface temperature (SST) from 1961 to 1990 near our study area, which averages 7.40±0.35°C for coldest month and 14.12±0.54°C for warmest month. Our reconstructed temperatures from the Neoglacial limpets showed slightly (0-1°C) colder winters, similar or warmer (1-1.8°C) summers compared to present SST record. One shell captured a year without a summer likely resulting from an eruption of the Katla volcanic system in Iceland. The reconstructed temperatures from the Roman Warm Period limpets showed colder winters (up to 2°C) and similar summers compared with present SST record. Our findings represent the first insights of SST variability at seasonal time scales for these two climate episodes in northwest Scotland.

Wang, T.; Surge, D. M.; Mithen, S.

2010-12-01

68

The use of enzymatic biomarkers in two marine invertebrates Nereis diversicolor and Patella vulgata for the biomonitoring of Tangier's bay (Morocco).  

PubMed

The fast increase of anthropogenic activities has led to a continual influx of xenobiotics into the marine ecosystems. Quantifying biochemical parameters in marine invertebrates makes possible the evaluation of pollutants' damaging effect. In fact, to examine the health state of Tangier's bay, we focused on the study of catalase, esterase, acetylcholinesterase and alpha-amylase activities as biomarkers in two species of marine invertebrates Nereis diversicolor (Polychaeta, Nereidae) and Patella vulgata (Mollusca, Prosobranchia), collected from different sites along the Mediterranean coastline of Tangier. Our results showed that these biochemical parameters are disturbed following the level of decreasing environmental quality, and for this reason they are promising in the biomonitoring studies of the Moroccan marine environment. PMID:18786724

Douhri, Hikmat; Sayah, Fouad

2009-02-01

69

A microdeletion of chromosome 9q33.3 encompasses the entire LMX1B gene in a Chinese family with nail patella syndrome.  

PubMed

Nail patella syndrome (NPS) is an autosomal dominant disorder characterized by nail malformations, patellar apoplasia, or patellar hypoplasia. Mutations within the LMX1B gene are found in 85% of families with NPS; thus, this gene has been characterized as the causative gene of NPS. In this study, we identified a heterozygous microdeletion of the entire LMX1B gene using multiplex ligation-dependent probe amplification (MLPA) in a Chinese family with NPS. The determination of the deletion breakpoints by Illumina genome-wide DNA analysis beadchip showed that the deletion was located in chromosome 9q33.3 and spanned about 0.66 Mb in size. This heterozygous deletion provides strong evidence for haploinsufficiency as the pathogenic mechanism of NPS. PMID:25380522

Jiang, Shujuan; Zhang, Jiubin; Huang, Dan; Zhang, Yuanyuan; Liu, Xiaoliang; Wang, Yinzhao; He, Rong; Zhao, Yanyan

2014-01-01

70

Quantitative T2 mapping of the patella at 3.0 T is sensitive to early cartilage degeneration, but also to loading of the knee  

PubMed Central

Objective The aim of the study was to explore the sensitivity and robustness of T2 mapping in the detection and quantification of early degenerative cartilage changes at the patella. Materials and methods Forty-two patients (22 women, 20 men) with a mean age of 30.3 years and a symptomatic cartilage defect of ICRS grade ?2 were examined using a 3 T MRI with an 8-channel knee coil. The cartilage lesion was graded based on high-resolution PD TSE and 3D isotropic TrueFISP images. T2 maps were calculated from a standard MESE-sequence, performed at the beginning and at the end of the scan (40 min in-between). Depending on the defect size, a region-of-interest (ROI) analysis was performed on 1–3 consecutive slices. Mean T2 values for the deep, superficial, and global layer as well as the zonal variation were compared among defect grades (ANOVA, post hoc Duncan-test) and over time (Student's t-test). Results T2-measurements directly correlated with the extent of cartilage defect (ICRS grade) at all layers and at both time-points. However, correlations were closer for the second measurement at the end of the scan. In this unloaded state, differences in T2-values became more pronounced and were significant even between cartilage of normal appearance adjacent to the defect and healthy cartilage of control patients (both ICRS grade 0). In contrast, there were no such differences among grades in the zonal variation at any time. Conclusion T2 mapping might be a sensitive method for the detection of early cartilage degeneration at the patella in the unloaded joint. PMID:21497472

Apprich, S.; Mamisch, T.C.; Welsch, G.H.; Stelzeneder, D.; Albers, C.; Totzke, U.; Trattnig, S.

2012-01-01

71

Quantitation of glycosaminoglycan metabolism in anatomically intact articular cartilage of the mouse patella: in vitro and in vivo studies with 35 S-sulfate, 3 H-glucosamine, and 3 H-acetate  

Microsoft Academic Search

We investigated the usefulness of the whole mouse patella to quantitate the synthesis of the glycosaminoglycan (GAG) backbone and its sulfation by intact murine articular cartilage, both in vitro and in vivo. Using 35S-sulfate, 3H-glucosamine, or 3H-acetate as precursors of GAG synthesis, it was found that more than 90% of the incorporated radioactivity was confined to the patellar cartilage layer

B. J. Vries; W. B. Berg; E. Vitters; L. B. A. Putte

1986-01-01

72

Cystic chondromalacia (endochondral pseudocyst) of the auricle.  

PubMed

We reviewed and studied the histologic features of 23 cases of pseudocysts of auricular cartilage. Our aim was to determine and describe the histologic spectrum of this condition and to delineate the histologic differential diagnostic points. Lesions for which this condition has been mistaken include relapsing polychondritis, chondrodermatitis nodularis helicis, traumatic perichondritis, hemangioma, chondroma, angiosarcoma, and chondrosarcoma. The pathologist who is familiar with the histologic patterns of this condition usually can recognize it readily. When biopsy specimens are small, and the diagnosis is uncertain, clinical features can often suggest the correct diagnosis. PMID:3755327

Heffner, D K; Hyams, V J

1986-08-01

73

Lateral force-displacement behaviour of the human patella and its variation with knee flexion--a biomechanical study in vitro.  

PubMed

This study measured the patellar lateral force-displacement behaviour at a range of knee flexion angles in normal human cadaver specimens. The knee extensor muscles were loaded in proportion to their physiological cross-sectional areas, the tensions being applied in physiological directions along the separate quadriceps muscles. Knee extension was blocked at a range of knee flexion angles from 0 to 90 degrees, and patellar lateral displacement versus force characteristics were measured. This experiment was repeated with three total muscle forces, 20, 175 and 350 N, which were held constant at all flexion angles. It was shown that similar stability variation was obtained with the different total muscle loads, and also the forces required to produce a range of patellar displacements (1.5, 9 mm) were examined. A 5 mm lateral patellar displacement required a constant displacing force (i.e. the patella had constant lateral stability) up to 60 degrees knee flexion, and then a significant increase at 90 degrees. The results were related to surgical and anatomical observations. PMID:9882047

Farahmand, F; Tahmasbi, M N; Amis, A A

1998-12-01

74

Field testing the Unified Classification System for periprosthetic fractures of the femur, tibia and patella in association with knee replacement: an international collaboration.  

PubMed

The Unified Classification System (UCS) was introduced because of a growing need to have a standardised universal classification system of periprosthetic fractures. It combines and simplifies many existing classification systems, and can be applied to any fracture around any partial or total joint replacement occurring during or after operation. Our goal was to assess the inter- and intra-observer reliability of the UCS in association with knee replacement when classifying fractures affecting one or more of the femur, tibia or patella. We used an international panel of ten orthopaedic surgeons with subspecialty fellowship training and expertise in adult hip and knee reconstruction ('experts') and ten residents of orthopaedic surgery in the last two years of training ('pre-experts'). They each received 15 radiographs for evaluation. After six weeks they evaluated the same radiographs again but in a different order. The reliability was assessed using the Kappa and weighted Kappa values. The Kappa values for inter-observer reliability for the experts and the pre-experts were 0.741 (95% confidence interval (CI) 0.707 to 0.774) and 0.765 (95% CI 0.733 to 0.797), respectively. The weighted Kappa values for intra-observer reliability for the experts and pre-experts were 0.898 (95% CI 0.846 to 0.950) and 0.878 (95% CI 0.815 to 0.942) respectively. The UCS has substantial inter-observer reliability and 'near perfect' intra-observer reliability when used for periprosthetic fractures in association with knee replacement in the hands of experienced and inexperienced users. Cite this article: Bone Joint J 2014;96-B:1669-73. PMID:25452371

Van der Merwe, J M; Haddad, F S; Duncan, C P

2014-12-01

75

MRI of Cartilage: Pathological Findings  

Microsoft Academic Search

\\u000a The most important clinical indications for magnetic resonance imaging (MRI) are assessment of cartilage in osteoarthritis\\u000a (OA), chronic or acute osteochondral injury including sports injuries, osteochondritis dissecans, chondromalacia patellae,\\u000a and inflammatory arthropathies (in particular before invasive therapy). In addition dedicated cartilage imaging is required\\u000a after invasive cartilage repair procedures or conservative therapies, including pharmacological therapies, to monitor treatment\\u000a effect. MR

Thomas M. Link

76

Get a kick out of this: the spectrum of knee extensor mechanism injuries  

Microsoft Academic Search

At the end of this article, the reader should be able to (1) recognise normal anatomy and anatomical variants of the extensor mechanism of the knee on various imaging modalities, including plain film, ultrasound and MRI; (2) diagnose a broad spectrum of EM injuries in adult and paediatric patients including patellar and quadriceps tendinopathy, Osgood–Schlatter disease, Sindig–Larsen–Johansson syndrome, chondromalacia patellae

Betty Tuong; Jeremy White; Luck Louis; Robyn Cairns; Gordon Andrews; Bruce B Forster

2011-01-01

77

Get a kick out of this: the spectrum of knee extensor mechanism injuries.  

PubMed

At the end of this article, the reader should be able to (1) recognise normal anatomy and anatomical variants of the extensor mechanism of the knee on various imaging modalities, including plain film, ultrasound and MRI; (2) diagnose a broad spectrum of EM injuries in adult and paediatric patients including patellar and quadriceps tendinopathy, Osgood-Schlatter disease, Sindig-Larsen-Johansson syndrome, chondromalacia patellae and patellar fractures on various imaging modalities; and (3) appreciate the important role of imaging in the diagnosis of musculoskeletal injuries. PMID:20966035

Tuong, Betty; White, Jeremy; Louis, Luck; Cairns, Robyn; Andrews, Gordon; Forster, Bruce B

2011-02-01

78

Pseudocyst of the auricle: a review of 21 cases.  

PubMed

Pseudocyst of the auricle (benign idiopathic cystic chondromalacia) is rare. Only 20 cases have been previously reported in the literature. Our study retrospectively reviews 21 additional cases. We conclude that idiopathic cystic chondromalacia can occur in both sexes, in all races, and at any age. The differential diagnoses for idiopathic cystic chondromalacia are relapsing polychondritis and chondrodermatitis nodularis chronica helicis. Recurrence of idiopathic cystic chondromalacia is uncommon following adequate local treatment. PMID:3083365

Lazar, R H; Heffner, D K; Hughes, G B; Hyams, V K

1986-03-01

79

Slipped capital femoral epiphysis: the importance of early diagnosis.  

PubMed

Slipped capital femoral epiphysis typically occurs in adolescents. Presentation may include limp or vague pain in the hip, thigh or knee. Knee pain, in particular, is a common complaint among adolescents and may be due to patello-femoral syndromes, Osgood-Schlatter disease, patellar tendonitis, or chondromalacia patella, to name a few. However, it is vital to remember that the complaint of knee pain may be present because of referred pain from pathology at the hip. Every child presenting with a complaint of hip, thigh or knee pain must undergo a hip examination. Likewise, a "groin pull" is exceedingly rare in children and must be a diagnosis of exclusion. Any child with complaints of hip, thigh, or knee pain, or physical examination findings of out-toeing, decreased internal rotation, or obligate external rotation with flexion, should be presumed to have SCFE until proven otherwise. There is a high rate of delay in diagnosis of SCFE, which leads to opportunities for progression of deformity, which in turn leads to increased risk of arthritis. Delay in diagnosis also may allow a stable SCFE to become an unstable one, with a much higher risk of development of AVN. When suspected, the diagnosis is confirmed with x-rays (AP and frog-lateral of the pelvis). Therefore, a high index of suspicion for this disorder, and the attainment of appropriate radiographs, should allow for prompt diagnosis and referral for treatment. Treatment is urgent and surgical. Early diagnosis and proper treatment are the mainstays of prevention of adverse sequelae. PMID:16493917

Katz, Daniellle A

2006-02-01

80

Anterior knee pain: an unusual presentation of renal cell carcinoma  

PubMed Central

Metastasis of any kind to the patella is rare. Metastasis to the patella causing symptoms representing the first presentation of underlying malignancy is rarer still. We report the case of a previously fit and well 74-year-old male presenting with left anterior knee pain. The initial diagnosis was osteoarthritis but after continued symptoms a diagnosis of solitary patella metastasis from a primary renal cell carcinoma was confirmed. PMID:24876400

Broomfield, John; Ralte, Peter; Morapudi, Syam; Vasireddy, Naveen; Kershaw, Steven

2014-01-01

81

Anterior knee pain: an unusual presentation of renal cell carcinoma.  

PubMed

Metastasis of any kind to the patella is rare. Metastasis to the patella causing symptoms representing the first presentation of underlying malignancy is rarer still. We report the case of a previously fit and well 74-year-old male presenting with left anterior knee pain. The initial diagnosis was osteoarthritis but after continued symptoms a diagnosis of solitary patella metastasis from a primary renal cell carcinoma was confirmed. PMID:24876400

Broomfield, John; Ralte, Peter; Morapudi, Syam; Vasireddy, Naveen; Kershaw, Steven

2014-01-01

82

Medial Patellofemoral Ligament Reconstruction: A Technique With a “V”-Shaped Patellar Tunnel  

PubMed Central

Patellofemoral dislocation is a common problem affecting the young and active population. The medial patellofemoral ligament (MPFL) is torn when the patella dislocates as it acts as a checkrein to lateral displacement. This leads to patellar instability, and MPFL reconstruction is required if the dislocation recurs after a trial of rehabilitation. We describe a “V”-shaped patellar tunnel technique to reconstruct the MPFL using an autologous gracilis graft. This modification of the patellar tunnel does not breach the lateral cortex of the patella, and it allows a broader attachment of the tendon graft to the patella, which mimics the normal anatomic attachment of the MPFL to the patella. PMID:25473612

Ahmad, Riaz; Jayasekera, Narlaka; Schranz, Peter; Mandalia, Vipul

2014-01-01

83

Tracheobronchial Involvement in Relapsing Polychondritis  

Microsoft Academic Search

Relapsing polychondritis (RPC) is a multisystem disorder of chondromalacia involving any cartilage. Respiratory tract involvement is the greatest threat to life. We report a patient with stenosis of the subglottic trachea and left main bronchus who suddenly ceased breathing. As this patient did not have any other clinical features of RPC, the diagnosis was difficult. CT showed circumferential worm-eaten-like thickening

Yoshio Tsunezuka; Hideo Sato; Hiroshi Shimizu

2000-01-01

84

Structure, ontogeny and evolution of the patellar tendon in emus (Dromaius novaehollandiae) and other palaeognath birds  

PubMed Central

The patella (kneecap) exhibits multiple evolutionary origins in birds, mammals, and lizards, and is thought to increase the mechanical advantage of the knee extensor muscles. Despite appreciable interest in the specialized anatomy and locomotion of palaeognathous birds (ratites and relatives), the structure, ontogeny and evolution of the patella in these species remains poorly characterized. Within Palaeognathae, the patella has been reported to be either present, absent, or fused with other bones, but it is unclear how much of this variation is real, erroneous or ontogenetic. Clarification of the patella’s form in palaeognaths would provide insight into the early evolution of the patella in birds, in addition to the specialized locomotion of these species. Findings would also provide new character data of use in resolving the controversial evolutionary relationships of palaeognaths. In this study, we examined the gross and histological anatomy of the emu patellar tendon across several age groups from five weeks to 18 months. We combined these results with our observations and those of others regarding the patella in palaeognaths and their outgroups (both extant and extinct), to reconstruct the evolution of the patella in birds. We found no evidence of an ossified patella in emus, but noted its tendon to have a highly unusual morphology comprising large volumes of adipose tissue contained within a collagenous meshwork. The emu patellar tendon also included increasing amounts of a cartilage-like tissue throughout ontogeny. We speculate that the unusual morphology of the patellar tendon in emus results from assimilation of a peri-articular fat pad, and metaplastic formation of cartilage, both potentially as adaptations to increasing tendon load. We corroborate previous observations of a ‘double patella’ in ostriches, but in contrast to some assertions, we find independent (i.e., unfused) ossified patellae in kiwis and tinamous. Our reconstructions suggest a single evolutionary origin of the patella in birds and that the ancestral patella is likely to have been a composite structure comprising a small ossified portion, lost by some species (e.g., emus, moa) but expanded in others (e.g., ostriches).

Pitsillides, Andrew A.; Hutchinson, John R.

2014-01-01

85

Modified pre-curved patellar basket plate, reconstruction of the proper length and position of the patellar ligament--a biomechanical analysis.  

PubMed

Biomechanical properties of basket plate fixation for fracture dislocation in the distal part of the patella were studied on 22 fresh-frozen lower extremities (human cadaveric knees). The patella and the patellar ligament with the proximal tibia were removed. A comminuted fracture of the distal part of the patella was created with a chisel. The fractured patella, patellar ligament and tibial tuberosity of each specimen were fixed with a basket plate and mounted into the jaws of the testing machine. The measured load to failure was 421.66+/-45.90 N, which is approximately 70% higher than the results in other studies. The results of the measurements verified the results of finite element analysis. The modified precurved patellar basket plate developed in this study showed improved performance compared to the pre-existing fixation methods. PMID:17433694

Krkovic, M; Bombac, D; Balazic, M; Kosel, F; Hribernik, M; Senekovic, V; Brojan, M

2007-06-01

86

Genetics Home Reference: Genitopatellar syndrome  

MedlinePLUS

... patellae, scrotal hypoplasia, renal anomalies, facial dysmorphism, and mental retardation GPS For more information about naming genetic conditions, ... gene ; histone ; hypoplasia ; hypotonia ; inheritance ; inheritance pattern ; joint ; ... microcephaly ; micrognathia ; molecule ; muscle tone ; nervous system ; pelvis ; ...

87

Three-dimensional anatomy of the ostrich (Struthio camelus) knee joint  

PubMed Central

The three-dimensional anatomy of the ostrich (Struthio camelus) knee (femorotibial, femorofibular, and femoropatellar) joint has scarcely been studied, and could elucidate certain mechanobiological properties of sesamoid bones. The adult ostrich is unique in that it has double patellae, while another similar ratite bird, the emu, has none. Understanding why these patellae form and what purpose they may serve is dually important for future studies on ratites as well as for understanding the mechanobiological characteristics of sesamoid bone development. For this purpose, we present a three-dimensional anatomical study of the ostrich knee joint, detailing osteology, ligaments and menisci, and myology. We have identified seven muscles which connect to the two patellae and compare our findings to past descriptions. These descriptions can be used to further study the biomechanical loading and implications of the double patella in the ostrich.

Regnault, Sophie; Allen, Vivian; Hutchinson, John R.

2014-01-01

88

Multiple osteochondroses of bilateral knee joints  

Microsoft Academic Search

We experienced a patient with a combination of multiple osteochondroses: Blount's disease, bipartite patella, and Sinding-Larsen-Johansson\\u000a disease in the left knee, and a combination of bipartite patella and Osgood-Schlatter disease in the right knee. The patient\\u000a was a healthy, active 12-year-old boy with bilateral knee pain. He had been diagnosed with Blount's disease of the left tibia\\u000a at 2 years

Hiroyuki Segawa; Go Omori; Yoshio Koga

2001-01-01

89

FOSSIL BLOOD DROPLETS IN MIOCENE DOMINICAN AMBER YIELD CLUES TO SPEED AND DIRECTION OF RESIN SECRETION  

Microsoft Academic Search

Two spiders (Filistatidae) in Miocene Dominican Republic amber, one newly identified and only the second known fossil of this family, have autospasized legs (detached at a predetermined locus of weakness when restrained by a non-self-induced source) at the patella-tibia joint. In both specimens, droplets of haemolymph (blood) are preserved exiting the patellae. The autospasized legs and the presence of haemolymph

DAVID PENNEY

2005-01-01

90

MR Pharmacokinetic Modeling of the Patellar Cartilage Differentiates Normal From Pathological Conditions  

Microsoft Academic Search

Purpose: To study the pharmacokinetic parameters de- rived from dynamic contrast-enhanced magnetic reso- nance imaging (DCE-MRI) of the patellar cartilage under normal and pathological conditions. Materials and Methods: DCE-MRI was obtained in 22 cases. There were 17 patients with degenerative patellar conditions (eight with chondromalacia and nine with osteoarthritis) and five normal subjects. The cartilage pharmacokinetic parame- ters of Ktrans

Roberto Sanz; Luis Marti ´-Bonmati ´; JoseLuis Rodrigo; David Moratal

2008-01-01

91

Patellofemoral anatomy and biomechanics: current concepts  

PubMed Central

The patellofemoral joint, due to its particular bone anatomy and the numerous capsuloligamentous structures and muscles that act dynamically on the patella, is considered one of the most complex joints in the human body from the biomechanical point of view. The medial patellofemoral ligament (MPFL) has been demonstrated to contribute 60% of the force that opposes lateral displacement of the patella, and MPFL injury results in an approximately 50% reduction in the force needed to dislocate the patella laterally with the knee extended. For this reason, recent years have seen a growing interest in the study of this important anatomical structure, whose aponeurotic nature has thus been demonstrated. The MPFL acts as a restraint during motion, playing an active role under conditions of laterally applied stress, but an only marginal role during natural knee flexion. However, it remains extremely difficult to clearly define the anatomy of the MPFL and its relationships with other anatomical structures.

ZAFFAGNINI, STEFANO; DEJOUR, DAVID; GRASSI, ALBERTO; BONANZINGA, TOMMASO; MUCCIOLI, GIULIO MARIA MARCHEGGIANI; COLLE, FRANCESCA; RAGGI, FEDERICO; BENZI, ANDREA; MARCACCI, MAURILIO

2013-01-01

92

Patellofemoral instability: surgical treatment of soft tissues  

PubMed Central

Summary Instability of the patella is a relatively frequent occurrence in adolescents. Its pathogenesis, which is multi-factorial, is still much debated. Stability of the patella is guaranteed by a delicate balance of a series of factors (osteo-cartilaginous, ligamentous and muscular), and it is not surprising that alteration of one or more of these can lead to pathological conditions that can range from simple anterior pain associated with a hypermobile patella to recurrent dislocation. The aim of surgical treatment is to correct these anatomical abnormalities. Surgical procedures on the soft tissues comprise reefing, realignment and reconstruction of the medial stabilizing structures, and release of the lateral structures. These procedures, although having precise indications, provide the surgeon with the instruments necessary to deal with almost all these anatomo-pathological conditions. Furthermore, preserving the osteo-cartilaginous components results in less morbidity than is associated with traditional surgical procedures, such as trochleoplasty and transposition of the anterior tibial tuberosity.

Panni, Alfredo Schiavone; Cerciello, Simone; Vasso, Michele

2013-01-01

93

“Central” Quadriceps Tendon Harvest With Patellar Bone Plug: Surgical Technique Revisited  

PubMed Central

The objective of this article is to review the surgical technique for quadriceps tendon graft harvest while highlighting an additional technical note that has not been previously emphasized. The quadriceps tendon typically inserts eccentrically on the superior pole of the patella. By shifting the soft-tissue harvest to a location just off the medial edge of the tendon, the adjoining patellar bone plug will be centered on the superior pole of the patella, reducing the risk of an iatrogenic patellar fracture. PMID:24400194

Scully, William F.; Wilson, David J.; Arrington, Edward D.

2013-01-01

94

[Knee dislocation treatment with temporary tibio-patellar fixation (patellar olecranization)].  

PubMed

Four patients with traumatic dislocation of the knee has been treated with olecranization of the patella. Mean age was 44.4 years (range 27-75 years). Three of them were politrauma patients, but none had popliteal artery injury or peroneal nerve palsy. Olecranization of the patella was performed on the day of injury. Results were assessed according to the Marshall scale. Three results were rated excellent and good with near normal knee function. In one case result was rated fair since despite stable knee and full range of motion pain persisted and marked vascular changes, not related to the injury were present. PMID:10423917

Nied?wiedzki, T; H?adki, W; Mierniczek, W

1999-01-01

95

Patellofemoral malalignment and chondral damage: current concepts  

PubMed Central

Patellofemoral disorders can be classified according to specific criteria, and the most well-known classification systems are Insall’s classification and Merchant’s classification. In this work, after completion of an in-depth literature review, we will analyze the most frequent patellofemoral pathologies with the aim of determining the correct clinical-diagnostic-therapeutic course. Pathologies of greater clinical frequency will be examined in detail to provide the most relevant didactic scope. We will therefore address the following pathologies: excessive lateral patellar compression syndrome; patellar dislocations and subluxations; patellar chondromalacia; and patellofemoral osteoarthritis.

MAZZOLA, CLAUDIO; MANTOVANI, DAVIDE

2013-01-01

96

Multiple, bilateral and painful ear nodules of the anthelices: a variant of chondrodermatitis nodularis?  

PubMed

A case of a distinctive clinicopathologic condition of the ear cartilage is presented, characterized by multiple, bilateral and painful nodules of the anthelices without epidermal involvement. Histologically, there was a peri-chondrial lymphohistiocytic infiltrate and a small focus of degenerate, basophilic cartilage as well as cystic chondromalacia containing an amorphous mass. This condition is both clinically and histopathologically distinct from other causes of ear nodules, although the lesions seen in our patient exhibit features of chondrodermatitis nodularis helices and therefore could well be a variant of the latter. PMID:12370141

Bogenrieder, Thomas; Allert, Max-Hubertus; Landthaler, Michael; Stolz, Wilhelm

2002-01-01

97

Hypointense signal lesions of the articular cartilage: a review of current concepts.  

PubMed

Discussion of articular cartilage disease detection by MRI usually focuses on the presence of bright signal on T2-weighted sequences, such as in Grade 1 chondromalacia and cartilage fissures containing fluid. Less emphasis has been placed on how cartilage disease may be manifested by dark signal on T2-weighted sequences. The appearance of the recently described "cartilage black line sign" of the femoral trochlea highlights these lesions and further raises the question of their etiology. We illustrate various hypointense signal lesions that are not restricted to the femoral trochlea of the knee joint and discuss the possible etiologies for these lesions. PMID:24928821

Markhardt, B Keegan; Chang, Eric Y

2014-01-01

98

The pathophysiology of Osgood-Schlatter disease: a magnetic resonance investigation.  

PubMed

Osgood-Schlatter disease (OSD) is a well-described clinical condition, although its origin remains controversial. Mechanical, growth or traumatic factors are suggested as causes of this lesion. Thirty-five patients were included in this study. Twenty of them had OSD (study group) and the remaining 15 adolescents constituted the control group. Magnetic resonance imaging of the knees was performed in all patients. The distance between the distal pole of the patella and the proximal margin of patellar tendon attachment to the tibial apophysis (A), the distance between the distal pole of the patella and the tibial tubercle epiphysis (B), the distance between the proximal margin of the patellar tendon attachment to the tibia and the tibial tubercle epiphysis (C) and the distance between the knee joint level and the tibial tubercle epiphysis (D) were measured. The ratio of the distance between the distal pole of the patella and the proximal margin of the patellar tendon attachment to the tibia to the distance between the distal pole of the patella and the tibial tubercle epiphysis (A : B) was lower in the study group. The ratio of the distance between the proximal margin of the patellar tendon attachment point to the tibia and the tibial tubercle epiphysis to the distance between the knee joint level and the tibial tubercle epiphysis (C : D) was higher in the control group. We conclude that if the patellar tendon attaches more proximally and in a broader area to the tibia, this might probably cause OSD. PMID:15599229

Demirag, Burak; Ozturk, Cagatay; Yazici, Zeynep; Sarisozen, Bartu

2004-11-01

99

The Coffin-Siris syndrome  

Microsoft Academic Search

We report a white female infant with typical features of Coffin-Siris syndrome including thick eyebrows, flat nasal bridge, anteverted, wide nose tip, generalised hypertrichosis, scalp hypotrichosis, absence of the fifth fingernails and toenails, absence of the distal phalanges of the fifth fingers and of the second to fifth toes, small patellae, inguinal hernia, and sucking and feeding difficulties. There was

Q H Qazi; L S Heckman; D Markouizos; R S Verma

1990-01-01

100

Radiographic patterns of osteoarthritis of the knee joint in the community: the importance of the patellofemoral joint  

Microsoft Academic Search

The intimate relation which the patella has with the knee joint and quadriceps muscle suggests that patellofemoral joint osteoarthritis is likely to be an important cause of knee pain and disability. Two hundred and seventy three subjects who reported knee pain in a postal questionnaire survey and 240 control subjects consented to have anteroposterior weightbearing and lateral knee radiographs. Each

T E McAlindon; S Snow; C Cooper; P A Dieppe

1992-01-01

101

Rapid recovery after Oxford unicompartmental arthroplasty through a short incision  

Microsoft Academic Search

Forty Oxford medial unicompartmental arthroplasties (UCAs) were performed through a short incision medial to the patellar tendon, without dislocation of the patella, using updated instruments (Oxford Knee Phase III, Biomet Ltd., Bridgend, UK). The rate of recovery of these knees (measured by the time taken to achieve straight-leg raising, 70° of flexion, and independent stair climbing) was compared with that

A. J. Price; J. Webb; H. Topf; C. A. F. Dodd; J. W. Goodfellow; D. W. Murray

2001-01-01

102

The MRI appearance of cystic lesions around the knee  

Microsoft Academic Search

This review presents a comprehensive illustrated overview of the wide variety of cystic lesions around the knee. The aetiology, clinical presentation, MRI appearances and differential diagnosis are discussed. Bursae include those related to the patella as well as pes anserine, tibial collateral ligament, semimembranosus–tibial collateral ligament, iliotibial and fibular collateral ligament–biceps femoris. The anatomical extension, imaging features and clinical significance

Catherine L. McCarthy; Eugene G. McNally

2004-01-01

103

Patellofemoral Syndrome: Therapeutic Regimen Based on Biomechanics  

PubMed Central

The clinician needs to rehabilitate the patient with the patellofemoral syndrome based on biomechanics and anatomy. If we understand the function of the patella and the forces acting upon it, we can educate our patients to ensure their compliance through both the treatment phase and future maintenance. PMID:21248869

Strother, R.T.; Samoil, D.

1989-01-01

104

Thickness of patellofemoral articular cartilage as measured on MR imaging: sequence comparison of accuracy, reproducibility, and interobserver variation  

Microsoft Academic Search

Objective. Since the thickness of cartilage is an important indicator of the status, progression and re- sponse to therapy of articular disorders, assessment of it is desirable. This study was undertaken to assess the ac- curacy, precision, and reliability of magnetic resonance (MR) measurements of articular cartilage. Methods. Fifteen cadaveric patellas were imaged in the axial plane at 1.5 T.

Marc D. van Leersum; Mark E. Schweitzer; Frank Gannon; Simon Vinitski; Geral Finkel; Donald G. Mitchell

1995-01-01

105

Total knee arthroplasty in a pseudoachondroplastic dwarfism patient with bilateral patellar dislocation.  

PubMed

Late presentation of congenital patellar dislocation with advanced osteoarthritis is rare. This article presents a case of a 59-year-old man with underlying pseudoachondroplastic dwarfism. Advanced osteoarthritis due to bilateral neglected congenital patellar dislocation was treated with total knee arthroplasty without patella relocation surgery. Two years later, the patient had an improvement in Knee Society scores, painless function, and stability. PMID:23177661

Oh, Kwang-Jun; Yoon, Jung-Ro; Yang, Jae-Hyuk

2013-01-01

106

Revision and salvage patellar arthroplasty using a porous tantalum implant 1 1 No benefits or funds were received in support of this study. Dr. Poggie is an employee of Zimmer Trabecular Metal Technology, Inc., Allendale, NJ  

Microsoft Academic Search

The purpose of this study was to assess the clinical results of a new surgical technique and novel porous tantalum implant for augmentation or arthroplasty of the patella for 11 patients who underwent revision total knee arthroplasty. Preoperative average knee function and pain scores were 24 and 20, respectively, and average range of motion (ROM) was 62°. The low knee

Sam Nasser; Robert A Poggie

2004-01-01

107

Subsistence shellfish harvesting in the Maputaland Marine Reserve in northern KwaZulu-Natal, South Africa: Rocky shore organisms  

Microsoft Academic Search

The shellfish harvest from c. 36 600 woman collecting days in the Maputaland Marine Reserve, KwaZulu-Natal, South Africa was monitored between 1988 and 1994. Mussels Perna perna (185 t), oysters Striostrea margaritacea and Saccostrea cucullata (5 t), red bait Pyura stolonifera (41 t flesh weight) and limpets Patella and Fissurella spp. (144 000 animals) were the main species harvested, although

R. Kyle; B. Pearson; P. J. Fielding; W. D. Robertson; S. L. Birnie

1997-01-01

108

Patellofemoral kinematics during knee flexion-extension: an in vitro study.  

PubMed

The purpose of this work was to obtain kinematics data for the normal human patellofemoral joint in vitro. Eight fresh-frozen cadaver knees were used. The heads of the quadriceps were separated, and the knees mounted in a kinematics rig. The femoral axis was aligned with an electromagnetic transmitter. The six heads of the quadriceps, including vasti medialis and lateralis obliquus, were loaded via cables according to their physiological cross-sectional areas and orientations. Magnetic trackers were mounted on the patella and tibia. The knee was flexed-extended against the extending muscle action, and patellar tracking was measured in six degrees of freedom. As the knee flexed, the patella flexed by 0.7 times the tibiofemoral flexion angle. It also translated medially 4 mm to engage the trochlear groove at 20 degrees knee flexion, then translated to 7 mm lateral by 90 degrees knee flexion. The patella tilted progressively to 7 degrees lateral by 90 degrees knee flexion, and patellar medial-lateral rotation was usually less than 3 degrees. This is believed to be the first set of patellar tracking data obtained in both flexion and extension motion while the patella was acted on by a full set of quadriceps muscle tensions acting in physiological directions. These data may be used in future studies of the effects of pathologies on patellar tracking. PMID:17004269

Amis, Andrew A; Senavongse, Wongwit; Bull, Anthony M J

2006-12-01

109

Endoscopic fixation of a double-looped semitendinosus and gracilis anterior cruciate ligament graft using bone mulch screw  

Microsoft Academic Search

Surgeons are switching to the four-bundled hamstring graft, composed of double-looped semitendinosus and gracilis tendons (DLSTG), to replace the torn anterior cruciate ligament. Mechanically, the DLSTG is superior; it is twice as strong and stiffer than a patella tendon graft, and the four bundles share load and mimic the function of the anteromedial and posterolateral bands of the native anterior

Stephen M. Howell; John Eibe Gottlieb

1996-01-01

110

Full arthroscopic lateral retinacular release with hook knife and quadriceps pressure-pull test: long-term follow-up  

Microsoft Academic Search

The most important causes of anterior knee pain include patellofemoral malalignment which causes patella–condyle contact anomalies at the patellofemoral joint, excessive patellar lateral pressure increase, trauma and overuse. In this article, besides presentation of late clinical results of 169 lateral retinacular release cases which were surgically treated between January 1995 and December 2002 with the help of a hook knife

Osman Ugur Calpur; Mert Ozcan; Hakan Gurbuz; Fatma Nesrin Turan

2005-01-01

111

Evidence of accumulated stress in Achilles and anterior knee tendons in elite badminton players.  

PubMed

Tendon-related injuries are a major problem, but the aetiology of tendinopathies is unknown. In tendinopathies as well as during unaccustomed loading, intra-tendinous flow can be detected indicating that extensive loading can provoke intra-tendinous flow. The aim of present study is to evaluate the vascular response as indicated by colour Doppler (CD) activity in both the Achilles and patella tendon after loading during high-level badminton matches. The Achilles tendon was subdivided into a mid-tendon, pre-insertional, and insertional region and the anterior knee tendons into a quadriceps-, patella- and tuberositas region. Intra-tendinous flow was measured using both a semi-quantitative grading system (CD grading) and a quantitative scoring system (CF) on colour Doppler. Intra-tendinous flow in the Achilles and anterior knee tendons was examined in fourteen single players before tournament and after 1st and 2nd match, respectively on both the dominant and non-dominant side. All players had abnormal intra-tendinous flow (Colour Doppler ? grade 2) in at least one tendon in at least one scan during the tournament. At baseline, only two of the 14 players had normal flow in all the tendons examined. After 1st match, tendencies to higher intra-tendinous flow were observed in both the dominant patella tendon and non-dominant quadriceps tendon (P-values n.s.). After 2nd match, intra-tendinous flow was significant increased in the dominant patella tendon (P = 0.009). In all other locations, there was a trend towards a stepwise increase in intra-tendinous flow. The preliminary results indicate that high amount of intra-tendinous flow was found in elite badminton players at baseline and was increased after repetitive loading, especially in the patella tendon (dominant leg). The colour Doppler measurement can be used to determine changes in intra-tendinous flow after repetitive loading. PMID:20652535

Boesen, Anders Ploug; Boesen, Morten Ilum; Koenig, Merete Juhl; Bliddal, Henning; Torp-Pedersen, Soren; Langberg, Henning

2011-01-01

112

Seasonality in the Western Mediterranean During the Last Glacial From Paired Oxygen Isotopes and Mg/Ca in Limpet Shells  

NASA Astrophysics Data System (ADS)

Molluscs have shown great potential to act as seasonal-resolution archives of sea-surface temperatures (SST) at mid to high latitudes, outside the range of tropical surface corals. Seasonal resolution climate records from higher latitudes are important to allow investigation of the role of seasonality in controlling mean climate on diverse timescales, and of the evolution of climate systems such as the North Atlantic Oscillation. Long sequences of intertidal mollusc shells are difficult to find due to sea level fluctuations over glacial- interglacial periods. This study makes use of Patella shells collected by Neanderthals and humans and transported inland to caves on Gibraltar over at least the last 120 kyrs. Some 30 fossil Patella shells were selected from several hundred excavated from Gorham's and Vanguard Caves at Gibraltar. Oxygen isotope analysis of micromilled samples of modern Patella shells from the Gibraltar coastline demonstrate that the shells accurately record absolute SSTs and capture more than 80% of the full seasonal range. Analysis of fossil Patella shells, dated using 14C, provides records of the change in absolute SST and seasonality during the last glacial. Paired Mg/Ca ratios of micromilled samples in modern Patella shells follow a consistent positive relationship with SST providing an independent paleothermometer, analogous with coral Sr/Ca. Applying this Mg/Ca-SST relationship to fossil Patella shells allows the independent reconstruction of the absolute values and range of SSTs and the reconstruction of seawater ?18O for the western Mediterranean. Results show a cooling of glacial summer SSTs from 36 kyr BP to the LGM with maximum cooling of glacial summer SSTs of 7.5 °C relative to modern. In contrast, winter SSTs show greater variability on millennial timescales with a maximum cooling of up to 10 °C. SST seasonality is therefore extended due to greater winter cooling but SST seasonality is highly variable as a result of large fluctuation in the extent of winter cooling. These results contrast with GCM model estimates of SST values and seasonality during the glacial.

Ferguson, J. E.; Henderson, G. M.; Fa, D.; Finlayson, C.

2008-12-01

113

Sinding-Larsen-Johansson syndrome: A case report  

PubMed Central

The Sinding-Larsen-Johansson syndrome has a pathogenesis similar to that of the Osgood-Schlatter disorder and is the result of excessive force exerted by the patellar tendon on the lower pole of the patella. Clinically it is characterized by pain, which increases when the patellar is loaded during flexion, subpatellar swelling and functional limitation. The authors present a case of a 13-year-old boy who was a competitive youth team football player. He presented with anterior, spontaneous knee pain and swelling at the inferior pole of the patella. Ultrasonography (US) confirmed clinical diagnosis showing lesions typical of the Sinding-Larsen-Johansson syndrome. The patient was told to refrain from sports activity; after five months recovery was complete and US follow-up revealed no anomaly. The authors consider the case worthy of reporting because it is paradigmatic and to emphasize the role of US in the evaluation of the Sinding-Larsen-Johansson syndrome. PMID:23396672

Valentino, M.; Quiligotti, C.; Ruggirello, M.

2012-01-01

114

Sinding-Larsen-Johansson syndrome: A case report.  

PubMed

The Sinding-Larsen-Johansson syndrome has a pathogenesis similar to that of the Osgood-Schlatter disorder and is the result of excessive force exerted by the patellar tendon on the lower pole of the patella. Clinically it is characterized by pain, which increases when the patellar is loaded during flexion, subpatellar swelling and functional limitation. The authors present a case of a 13-year-old boy who was a competitive youth team football player. He presented with anterior, spontaneous knee pain and swelling at the inferior pole of the patella. Ultrasonography (US) confirmed clinical diagnosis showing lesions typical of the Sinding-Larsen-Johansson syndrome. The patient was told to refrain from sports activity; after five months recovery was complete and US follow-up revealed no anomaly. The authors consider the case worthy of reporting because it is paradigmatic and to emphasize the role of US in the evaluation of the Sinding-Larsen-Johansson syndrome. PMID:23396672

Valentino, M; Quiligotti, C; Ruggirello, M

2012-06-01

115

The immature athlete.  

PubMed

The skeletally immature athlete poses unique problems in diagnosis and treatment of injuries to the extensor mechanism of the knee. An accurate and detailed history and physical examination of the knee are essential for making a specific diagnosis and formulating an appropriate treatment plan. This article presents an overview of acute and chronic injuries of the extensor mechanism of the knee that are unique to skeletally immature athletes. The subjects of femoral trochlear dysplasia and medial subluxation of the patella are briefly discussed. The etiopathology, clinical evaluation, and management (non-operative and operative) of sleeve fractures of the patella and avulsion fractures of the tibial tubercle in children and adolescents are discussed. The pathoanatomy, clinical features, and management of synovial plica syndrome, Hoffa's syndrome, Osgood-Schlatter disease, and Sinding-Larsen-Johansson disease are presented. PMID:12365238

Duri, Zaid A A; Patel, Dipak V; Aichroth, Paul M

2002-07-01

116

Extensor-mechanism-reconstruction of the knee joint after traumatic loss of the entire extensor apparatus.  

PubMed

Injuries to the extensor apparatus of the knee joint have an incidence of 0.5% to 6%. Although previous studies have described the advantages and disadvantages of operative treatment in cases of patellar tendon rupture, patella fracture or quadriceps tendon lesions, a report on the reconstruction of the extensor apparatus after traumatic loss of the patella, the patellar tendon, the tibial tuberosity and parts of the lateral quadriceps muscle is absent from the literature. We present the case of a young motorcyclist who underwent a reconstruction of the extensor apparatus using autologous tendon grafts. At a 24-month follow-up, the patient has a nearly physiological range of motion of the knee joint and is able to cope well with everyday life. PMID:24702824

Raschke, D; Schüttrumpf, J P; Tezval, M; Stürmer, K M; Balcarek, P

2014-06-01

117

Knee extensor disruption in mild diplegic cerebral palsy: a risk for adolescent athletes  

PubMed Central

We report three cases of adolescent boys with mild diplegic cerebral palsy (CP) who suffered disruption of the knee extensor mechanism. Two had fractures of the patella and the third a fracture avulsion of the tibial tubercle combined with an undisplaced fracture of the patella. All three had gait analysis prior to sustaining the fractures and were known to have mild knee crouch. Each participated in sport including football. Each suffered an acute deterioration in gait resulting in a referral for repeat gait analysis, and x-ray of the affected knee. With the increased involvement of children with CP in sporting activities, especially children with mild knee crouch, we caution that knee extensor rupture might be an increasing problem. PMID:23429018

Elhassan, Yahya; O'Sullivan, Rory; Walsh, Mike; O Brien, Tim

2013-01-01

118

Mutations in the pre-replication complex cause Meier-Gorlin syndrome.  

PubMed

Meier-Gorlin syndrome (ear, patella and short-stature syndrome) is an autosomal recessive primordial dwarfism syndrome characterized by absent or hypoplastic patellae and markedly small ears¹?³. Both pre- and post-natal growth are impaired in this disorder, and although microcephaly is often evident, intellect is usually normal in this syndrome. We report here that individuals with this disorder show marked locus heterogeneity, and we identify mutations in five separate genes: ORC1, ORC4, ORC6, CDT1 and CDC6. All of these genes encode components of the pre-replication complex, implicating defects in replication licensing as the cause of a genetic syndrome with distinct developmental abnormalities. PMID:21358632

Bicknell, Louise S; Bongers, Ernie M H F; Leitch, Andrea; Brown, Stephen; Schoots, Jeroen; Harley, Margaret E; Aftimos, Salim; Al-Aama, Jumana Y; Bober, Michael; Brown, Paul A J; van Bokhoven, Hans; Dean, John; Edrees, Alaa Y; Feingold, Murray; Fryer, Alan; Hoefsloot, Lies H; Kau, Nikolaus; Knoers, Nine V A M; Mackenzie, James; Opitz, John M; Sarda, Pierre; Ross, Alison; Temple, I Karen; Toutain, Annick; Wise, Carol A; Wright, Michael; Jackson, Andrew P

2011-04-01

119

Reconstruction of a ruptured patellar tendon using ipsilateral semitendinosus and gracilis tendons with preserved distal insertions: two case reports  

PubMed Central

Background Acute patellar tendon ruptures with poor tissue quality. Ruptures that have been neglected are difficult to repair. Several surgical techniques for the repair of the patellar tendon have been reported, however, these techniques remain difficult because of contractures, adhesions, and atrophy of the quadriceps muscle after surgery. Case presentation We report the cases of 2 Japanese patients (Case 1: a 16-year-old male and Case 2: a 43-year-old male) with patellar tendon ruptures who were treated by reconstruction using semitendinosus-gracilis (STG) tendons with preserved distal insertions. Retaining the original insertion of the STG appears to preserve its viability and provide the revascularization necessary to accelerate healing. Both tendons were placed in front of the patella, in a figure-of-eight fashion, providing stability to the patella. Conclusion Both patients recovered near normal strength and stability of the patellar tendon as well as restoration of function after the operation. PMID:24010848

2013-01-01

120

Diagnosis and treatment of lateral patellar compression syndrome.  

PubMed

Chronic anterior knee pain with a stable patella is often associated with overload and increased pressure on the lateral facet due to pathologic lateral soft-tissue restraints. "Lateral pressure in flexion" is a term describing the pathologic process of increasing contact pressure over the lateral patellar facet as knee flexion progresses. This report describes a surgical technique developed in response to lateral pressure in flexion and the shortcomings of traditional arthroscopic lateral release procedures. The technique is performed open with the knee in flexion, and the lateral release is repaired with a rotation flap of iliotibial band to close the defect and prevent patellar subluxation. The technique effectively decreases lateral patellar pressure and centers the patella correctly in the trochlear groove with minimal risk of iatrogenic patellar instability. PMID:25473620

Saper, Michael G; Shneider, David A

2014-10-01

121

Correction of knee deformity in patients with Ellis-van Creveld syndrome: A case report and review of the literature.  

PubMed

Ellis-van Creveld Syndrome (EVC) is a rare autosomal recessive disorder. In 1940 Richard W. Ellis and Simon van Creveld first reported on a rare skeletal dysplasia, which to emphasize the main clinical characteristics, was termed "chondro-ectodermal dysplasia". The ectodermal involvement includes the skin, hair and nails while the chondrodysplastic characteristics involve the cartilage and bones, primarily in the forearms and lower legs. For the orthopaedic surgeon progressive valgus knee deformity accompanied by patella dislocation is the main problem in EVC. This study reports a ten year follow-up after a primarily failed operative therapy of knee deformity due to incomplete correction and the surgical technique utilized to correct the residual external torsional deformity and dislocation of the patella in a 19 year old girl who presented with the typical clinical features of Ellis-van Creveld Syndrome. PMID:21470865

Jöckel, Jens Arne; Reichel, Heiko; Nelitz, Manfred

2012-06-01

122

Bursae around the knee joints  

PubMed Central

A bursa is a fluid-filled structure that is present between the skin and tendon or tendon and bone. The main function of a bursa is to reduce friction between adjacent moving structures. Bursae around the knee can be classified as those around the patella and those that occur elsewhere. In this pictorial essay we describe the most commonly encountered lesions and their MRI appearance. PMID:22623812

Chatra, Priyank S

2012-01-01

123

In-vitro measurement of the human knee joint motion during quadriceps leg raising  

Microsoft Academic Search

This paper represents a three-dimensional motion analysis of the human knee joint under given conditions of loading and constraint.\\u000a As the knee is extended by a known force applied to the quadriceps tendon, relative displacements of the femur, tibia, and\\u000a patella are measured using a video motion analysis system. The most prominent motion of the tibia is external rotation and

Seonpil Kim

1998-01-01

124

Patello-femoral and tibio-femoral contact forces during kicking type of activity  

SciTech Connect

In this paper patello-femoral and tibia-femoral contact forces during kicking type of activity is presented by means of a dynamic model of the knee joint which includes tibio-femoral and patello-femoral articulations, and the major ligaments of the joint. The model shows that the patella can be subjected to very large transient patello-femoral contact forces during a strenuous lower limb activity such as kicking even under conditions of small knee-flexion angles.

Engin, A.E. [Univ. of South Alabama, Mobile, AL (United States); Tumer, S.T. [Middle East Technical Univ., Ankara (Turkey)

1996-12-31

125

How severe must repetitive loading be to kill chondrocytes in articular cartilage?  

Microsoft Academic Search

Objective Little is known about the effects of severe repetitive loading on articular cartilage chondrocytes, even though epidemiological studies associate this type of loading with osteoarthritis. We hypothesize that repetitive loading can kill cartilage chondrocytes in a dose-related manner.Design Large cartilage-on-bone specimens were cut from the patella groove of bovine knees obtained directly from a slaughterhouse. Cartilage was loaded using

K. M. Clements; Z. C. Bee; G. V. Crossingham; M. A. Adams; M. Sharif

2001-01-01

126

Diagnostik von Knorpelschäden des Kniegelenks  

Microsoft Academic Search

ZusammenfassungZielstellung  Anliegen der Arbeit war es, die Validität der präoperativen klinischen Untersuchung, der radiologischen Befunde und der MRT bei der Diagnostik chondraler Schäden des Kniegelenks im Vergleich zur Arthroskopie zu bestimmen.Methode  Bei 721 Patienten mit Kniebeschwerden die 3 Monate oder länger andauerten, erfolgte die standardisierte klinische Diagnostik (Grinding-Test), die radiologische Standarddiagnostik (Standaufnahmen und Patella-Axial-Aufnahme) sowie die MRT-Untersuchung (T1- und T2-Wichtung). Alle Patienten wurden nachfolgend

G. Spahn; R. Wittig; E. Kahl; H. M. Klinger; T. Mückley; G. O. Hofmann

2007-01-01

127

Ultrasonography of entheseal insertions in the lower limb in spondyloarthropathy  

Microsoft Academic Search

Objective: To compare ultrasonography (US) with clinical examination in the detection of entheseal abnormality of the lower limb in patients with spondyloarthropathy (SpA).Methods: 35 patients with SpA (ankylosing spondylitis 27; psoriatic arthritis 7; reactive arthritis 1) underwent independent clinical and ultrasonographic examination of both lower limbs at five entheseal sites—superior pole and inferior pole of patella, tibial tuberosity, Achilles tendon,

P V Balint; D Kane; H Wilson; I B McInnes; R D Sturrock

2002-01-01

128

Acro-spondylo-pubic dysostosis associated with cataracts, microcephaly, and normal intelligence.  

PubMed

We report on an adult male with normal intelligence who exhibited an unusual combination of microcephaly, dysostoses of limbs, vertebrae, patellae, and pubic bone, camptodactyly of all fingers, and syndactyly of toes, absent nails on thumbs and some fingers, bilateral cataract, cryptorchidism, polythelia, and nipple-like skin pigmentations of shoulders and upper back. We have been unable to find a description of a similar combination of manifestations in literature. The cause of the anomalies remains unknown. © 2014 Wiley Periodicals, Inc. PMID:25427842

Chacon-Camacho, Oscar F; Villegas-Ruiz, Vanessa; Buentello-Volante, Beatriz; Piña-Aguilar, Raul E; Peláez-González, Hugo; Ramírez, Magdalena; González-Rodríguez, Johanna; Zenteno, Juan Carlos

2014-11-26

129

A modified Gritti-Stokes amputation: its place in the management of peripheral vascular disease.  

PubMed

A modified technique for performing the Gritti-Stokes amputation is described and the results obtained in 247 cases are presented. The mortality rate was 9.3% and healing occurred in 87% of survivors. Using this modified technique the frequently cited criticisms of non-union of the patella and painful stumps were not found to be major problems. The prosthetic problems of amputation at this level are discussed in relation to recent developments in the design of artificial limbs. PMID:6830137

Beacock, C J; Doran, J; Hopkinson, B R; Makin, G S

1983-03-01

130

Regional variations in human patellar trabecular architecture and the structure of the proximal patellar tendon enthesis.  

PubMed

Proximal patellar tendinopathy occurs as an overuse injury in sport and is also characteristic of ankylosing spondylitis patients. It particularly affects the posteromedial part of the patellar tendon enthesis, although the reason for this is unclear. We investigated whether there are regional differences in the trabecular architecture of the patella or in the histology of the patellar tendon enthesis that could suggest unequal force transmission from bone to tendon. Trabecular architecture was analysed from X-rays taken with a Faxitron radiography system of the patellae of dissecting room cadavers and in magnetic resonance images of the knees of living volunteers. Structural and fractal analyses were performed on the Faxitron digital images using MatLab software. Regional differences at the enthesis in the thickness of the uncalcified fibrocartilage and the subchondral plate were evaluated histologically in cadaveric material. The radiological studies showed that the quantity of bone and the apparent trabecular thickness in the patella were greatest medially, and that in the lateral part of the patella there were fewer trabeculae which were orientated either antero-posteriorly or superiorly inferiorly. The histological study showed that the uncalcified fibrocartilage was most prominent medially and that the subchondral plate was thinner laterally. Overall, the results indicate that mechanical stress at the proximal patellar tendon enthesis is asymmetrically distributed and greater on the medial than on the lateral side. Thus, we suggest that the functional anatomy of the knee is closely related to regional variations in force transmission, which in turn relates to the posteromedial site of pathology in proximal patellar tendinopathy. PMID:16420378

Toumi, H; Higashiyama, I; Suzuki, D; Kumai, T; Bydder, G; McGonagle, D; Emery, P; Fairclough, J; Benjamin, M

2006-01-01

131

Quadriceps cross-sectional area changes in young healthy men with different magnitude of Q angle  

Microsoft Academic Search

Abstract Knee pain and dysfunction has been often associated with an ineffective pull of the patella by the vastus medialis relative to the lateralis, particularly in individuals with knee joint malalignment. Such changes,in muscular,behaviour may,be attributed,to muscle inhibition and\\/or atrophy that precede the onset of symptoms. The aim of this study was to investigate possible effects of knee joint malalignment,

Aikaterini E. Tsakoniti; Christoforos A. Stoupis; Spyros I. Athanasopoulos

2008-01-01

132

Comparison of insall-salvati ratios in children with an acute anterior cruciate ligament tear and a matched control population.  

PubMed

OBJECTIVE. An anterior cruciate ligament (ACL) injury is an increasingly recognized cause of knee pain in young patients and in athletes in particular and can be detected non-invasively with MRI. Anecdotal information suggests that patella alta may be more common in the setting of this injury, but no study has documented this phenomenon. This study sought to test whether an ACL tear is associated with an increased Insall-Salvati ratio suggestive of patella alta. MATERIALS AND METHODS. Measurements of patellar height, patellar tendon length, and the Insall-Salvati ratio obtained from MRI of the knee were compared for 34 children with an arthroscopically proven ACL tear (mean age ± SD, 12.4 ± 1.4 years) and 36 control subjects with normal knee examinations (12.8 ± 2.1 years); these measurements were performed independently by two observers. RESULTS. Patellar tendon length (47.6 ± 6.6 mm vs 40.4 ± 5.7 mm) and patellar position calculated as the Insall-Salvati ratio (1.16 ± 0.16 vs 0.99 ± 0.14) were significantly greater in the knees with an ACL injury than in those without an internal injury, respectively, on MRI (p < 0.001). Patella length was not significantly different between the two groups (patients vs control subjects, 41.1 ± 4.2 mm vs 40.6 ± 2.7 mm, respectively; p = 0.523). There was good to excellent interobserver and intraobserver correlation for all measurements. CONCLUSION. There is a significant association between an ACL tear and increased patellar tendon length with a greater Insall-Salvati ratio. The mechanism for this finding is unclear, but this association provides support to suggest relative patella alta may be a risk factor for ACL injuries in pediatric patients. PMID:25539252

Degnan, Andrew Joseph; Maldjian, Catherine; Adam, Richard J; Fu, Freddie H; Didomenico, Marica

2015-01-01

133

A case of patellar fractures in monozygotic twin gymnasts  

PubMed Central

We present a case of near identical patellar fractures in adolescent monozygotic twins who are both high-level competitive gymnasts. These patients presented 14 months apart with almost identical history and clinical findings. Both had an intense training regime involving over 30 hours per week of load-bearing exercise. Clinical and radiological examinations suggested avulsion or sleeve fracture of the inferior pole of the patella with minimal displacement. Diagnoses of patellar stress fracture with avulsion of the distal pole and symptomatic bipartite patella could not be reliably excluded. Both fractures were treated conservatively with immobilisation of the knee in extension. An excellent functional result was observed in both patients with return to full activity at 8 weeks. This is the first published case of identical injury to the patella in monozygotic twins. A significant genetic influence on bone mineral density (BMD) has been reported and low BMD is associated with increased susceptibility to fracture. These injuries corroborate a genetic influence on susceptibility to fracture. There is a requirement for further work to investigate genetic factors influencing susceptibility to fracture. PMID:22691448

2012-01-01

134

Multiple osteochondroses of bilateral knee joints.  

PubMed

We experienced a patient with a combination of multiple osteochondroses: Blount's disease, bipartite patella, and Sinding-Larsen-Johansson disease in the left knee, and a combination of bipartite patella and Osgood-Schlatter disease in the right knee. The patient was a healthy, active 12-year-old boy with bilateral knee pain. He had been diagnosed with Blount's disease of the left tibia at 2 years of age, and had been treated with open wedge osteotomy. He was diagnosed with bilateral bipartite patellae at the age of 9 years, and was diagnosed with Osgood-Schlatter disease in the right knee and Sinding-Larsen-Johansson disease in the left knee at 10 years of age. The second growth spurt was observed during this period. At 11 years of age, he was diagnosed with an osteochondral fracture of the left lateral femoral condyle and was observed without surgery. This patient showed the sequential appearance of an ossification disorder, probably due to the abnormal response of enchondral ossification to mechanical stress. Overuse in this growth period may have played a role in the development of these osteochondroses. The osteochondral fracture was probably caused by a disruption at one of the weakest parts of the developing skeleton, between the ossification center and the overlying cartilage in the background of an ossification disorder. PMID:11484125

Segawa, H; Omori, G; Koga, Y

2001-01-01

135

Discrepancies of Patellofemoral Indices between Supine and Standing Merchant Views  

PubMed Central

Purpose This research was conducted to compare supine and standing Merchant views, to observe radiographic changes of the patellofemoral joint according to weight-bearing conditions, and to evaluate correlation factors affecting patellofemoral joint indices. Materials and Methods Forty-four patients without skeletal problems were selected for this study. Patellar tilt angle, lateral patellofemoral angle, congruence angle, lateral subluxation distance and lateral patellar displacement were measured on each radiograph and evaluated for statistical significance. Possible correlation factors that can affect the radiographic discrepancy were analyzed using the univariate and multivariate regression analysis. Results In the standing Merchant view, the patellar tilt angle, congruence angle and lateral patellar displacement were significantly decreased (p<0.001), whereas the lateral patellofemoral angle was significantly increased (p<0.001) compared to that in the supine Merchant view. Thigh width (p<0.001, r2=0.22) and radiographic Q-angle (p<0.001, r2=0.34) were found correlated with the radiographic discrepancy of congruence angle. Discrepancy of the lateral patella displacement increased as radiographic Q-angle increased (p=0.027, r2=0.112). Conclusions Compared with the supine Merchant view, standing (weight-bearing) Merchant view showed decreased patella tilt angle, congruence angle, and lateral patella displacement. The results indicate that both supine and standing Merchant views should be considered in the radiographic evaluation of the patellofemoral joint. PMID:24639943

Kim, Tae-Hoon; Lee, Jong-Soo

2014-01-01

136

Patellofemoral Crepitus after Total Knee Arthroplasty: Etiology and Preventive Measures  

PubMed Central

Patellofemoral crepitus and clunk syndrome are infrequent, yet troublesome complications of total knee arthroplasty with a reported incidence of 0%-18%. They are primarily associated with implantation of posterior cruciate substituting designs. These entities are the result of peripatellar fibrosynovial hyperplasia at the junction of the superior pole of the patella and the distal quadriceps tendon which becomes entrapped within the superior aspect of the intercondylar box of the femoral component during knee flexion. When the knee extends, a crepitant sensation occurs as the fibrosynovial tissue exits the intercondylar box. Numerous etiologies have been proposed such as femoral component designs with a high intercondylar box ratio, previous knee surgery, reduced patellar tendon length, thinner patellar components, reduced patella-patellar component composite thickness, and smaller femoral components. Preventative measures include choice of femoral components with a reduced intercondylar box ratio, use of thicker patellar components, avoidance of over-resection of the patella, and debridement of the fibrosynovial tissue at the time of knee arthroplasty. Most patients with crepitus are unaware of the problem or have minimal symptoms so that no treatment is required. If significant disability is incurred, symptoms can be eliminated in a high percentage of patients with arthroscopic debridement of the fibrosynovial hyperplasia. PMID:24605184

Conrad, David N.

2014-01-01

137

Patellar malalignment treatment in total knee arthroplasty  

PubMed Central

Summary The patella, with or without resurfacing, plays a fundamental role in the success of a total knee arthroplasty (TKA). Patellofemoral joint complications are due to problems related to the patient, to the surgical technique, or to the design of the components. Patellar tracking is influenced by several factors: a severe preoperative valgus, the presence of pre-existing patellofemoral dysplasia, the design of the femoral component, the surgical approach, the Q angle, the mechanical alignment of the limb, the tightness of the lateral retinaculum, the positioning of the patellar component in the proximal-distal and medial-lateral directions, the patella height, the patella (native or resurfaced) thickness, the size of the femoral and the tibial components, and the alignment and rotation of the components. Several factors are crucial to prevent patellar maltracking in TKA: the use of an anatomical femoral component, a meticulous surgical technique, careful dynamic intraoperative assessment of patellar tracking, and, if necessary, the achievement of an adequate lateral release.

Gasparini, Giorgio; Familiari, Filippo; Ranuccio, Francesco

2013-01-01

138

Management of a difficult knee problem.  

PubMed

Chronic disabling patellofemoral (PF) pain and instability can have significant effects on patient function and lifestyle. Although the management of PF pain has improved greatly, there is still a category of patient who tends to have recalcitrant symptoms, which are difficult to manage. The patient often bounces from practitioner to practitioner, physiotherapist as well as surgeon, for some relief of symptoms. However, often the underlying source of the pain is not well understood, so treatment can aggravate the symptoms. The following case report demonstrates the effectiveness of physiotherapy in managing a complex clinical case of a 40 year old patient with bilateral PF symptoms of severe right knee pain and a subluxing left patella, as well as left hip pain. Some background is given as to the source of the right knee pain with magnetic resonance imaging (MRI) supporting the diagnosis and treatment progression. The initial MRI demonstrated marked redundancy of the patellar tendon, resulting in patella baja (infera). Two years and ten treatments later, the patient, who originally could barely walk, was playing tennis for the first time in 25 years. Her MRI showed a complete resolution of the patella baja (infera), indirectly implying an improvement in quadriceps tone, as well as, resolution of the subchondral bone marrow oedema at the lateral patellar facet. Physiotherapists should not give up on patients with chronic musculoskeletal conditions as much can be done for them. These patients need clinicians to persevere, because certainly, for both patient and therapist, the rewards are great. PMID:22748203

McConnell, Jenny

2013-06-01

139

Patellar tendon length after anterior cruciate ligament reconstruction: a comparative magnetic resonance imaging study between patellar and hamstring tendon autografts.  

PubMed

Patellar tendon shortening after anterior cruciate ligament reconstruction may be associated with anterior knee pain or patellofemoral arthritis. The present study was designed to compare postoperative changes in patellar tendon length after anterior cruciate ligament reconstruction between patellar tendon and hamstring tendon autograft. Magnetic resonance images of both knees (operated and healthy) and functional outcome were documented at least 1 year postoperatively in 16 patellar tendon harvested patients and in 32 hamstrings harvested patients. Patellar tendon length, patella length and Insall-Salvati ratio were measured. The operated knee values were compared to the respective values of the non-operated control knees. A significant 4.2 mm or 9.7% patellar tendon shortening in patellar tendon group and a non-significant 1.14 mm or 2.6% shortening in hamstrings group was detected. No significant difference was detected in terms of major shortening-patella baja-(6% for the patellar tendon group vs. 0% for the hamstring group). There was no significant difference in anterior knee problems between the two groups as evidenced by the Shelbourne score (94 for the patellar tendon group vs. 98 for the hamstring group). Harvesting of the patellar tendon for anterior cruciate ligament reconstruction resulted in a significant shortening of the remaining tendon. In contrast harvesting of the hamstring tendons did not affect significantly the patellar tendon length. However, the incidence of patella baja and overall functional outcome was not significantly different between the two groups. PMID:17225175

Hantes, Michael E; Zachos, Vasilios C; Bargiotas, Konstantinos A; Basdekis, Georgios K; Karantanas, Apostolos H; Malizos, Konstantinos N

2007-06-01

140

Elbow arthroscopy: valgus extension overload.  

PubMed

Valgus torque combined with deceleration produces high compression and shear forces acting on the posteromedial olecranon and the posteromedial trochlea. This valgus extension overload process may cause posteromedial trochlea chondromalacia, chondral flap formation, osteochondrosis, subchondral erosion, a subchondral insufficiency fracture, and marginal exostosis formation. Olecranon pathologies include proximal stress reaction, a posteromedial tip stress fracture, a transverse proximal process stress fracture, exostosis formation, exostosis fragmentation, and intra-articular loose bodies. Symptoms include posteromedial elbow pain during the deceleration phase of the throwing motion. The extension impingement test reproduces posterior or posteromedial pain similar to that experienced while throwing. Special radiographic techniques and CT scans can show loose bodies and osteophyte fragmentation. Surgical treatment is indicated when symptoms persist despite nonsurgical management. Based on clinical and basic science research, all patients with valgus extension overload should be comprehensively evaluated for medial ulnar collateral ligament insufficiency. Surgical treatment is limited to the resection of osteophytes only; normal olecranon should not be resected. PMID:21553773

Ahmad, Christopher S; Conway, John E

2011-01-01

141

Spectrum of intra-articular findings of the acute and subacute painful hip with multiple epiphyseal dysplasia/spondyloepiphyseal dysplasia.  

PubMed

Seven patients (10 hips), five with multiple epiphyseal dysplasia and two with spondyloepiphyseal dysplasia, were studied as to the etiology of a significant change in their baseline symptoms. Patients presented with decreased activity due to increased pain and mechanical symptoms and had a positive impingement test on physical examination. Three patients had a sudden increase in pain during normal walking and had subsequent difficulty with weight bearing. Arthrotomy or arthroscopy was used to identify the intra-articular pathology. Findings included loose bodies, chondromalacia, and labral pathology. Chondral avulsion fractures were found in the three patients who had a sudden increase in symptoms. Significant intra-articular pathology can develop in patients with multiple epiphyseal dysplasia or spondyloepiphyseal dysplasia. PMID:21691226

Roy, Dennis R

2011-09-01

142

Reconstruction of the anterior cruciate ligament: a comparison between bone-patellar tendon-bone grafts and fourstrand hamstring grafts  

PubMed Central

Background: Disruption of anterior cruciate ligament (ACL) is a common ligamentous injury of the knee. The choice of graft for (ACL) reconstruction remains controversial. This prospective, randomized clinical trial aimed to compare clinical results of bone-patellar tendon-bone (BPTB) grafts and four-strand semitendinosus-gracilis (ST) grafts for ACL reconstruction over a 3-year follow-up interval. Methods: Seventy-one patients with an average age of 29± 4.5yearswere treated for torn ACL between 2008 and 2009. Forty-sixpatients underwent reconstruction with BPTB autograft, and 41 were treated with ST autograft. At the time of final follow-up, 37 patients in patella group and 34 patients in hamstring group were evaluated in terms of return to pre-injury activity level, pain, knee stability, range of motion, IKDC (International Knee Documentation Committee) score and complications. Results: At 36thmonth of follow-up, 34 (92%) and 28 (82%) patients in BPTB and ST group, respectively had good-to-excellent IKDC score (p > 0.05). The activity levels were higher in BPTB group (p> 0.05). At 3rd yearof follow up, the Lachman test was graded normal, for 23 (62%) and 11 (32%) patients in BPTB and ST group, respectively (p=0.019). Regarding the pivot-shift test, 29 (79%) and 15 (44%) patients in patella and hamstring group, respectively had normal test at the latest follow-up (p=0.021).There were no significant differences in terms of thigh circumference difference, effusion, knee range of motion, pain and complications. Conclusion: The results indicate a trend toward increased graft laxity and pivot-shift grades in patients undergoing reconstruction with hamstring autograft compared with patella tendon. However, the two groups had comparable results in terms of activity level and knee function.

Razi, Mohammad; Sarzaeem, Mohammad Mahdi; Kazemian, Gholam Hossein; Najafi, Farideh; Najafi, Mohammad Amin

2014-01-01

143

Computational Wear Simulation of Patellofemoral Articular Cartilage during In Vitro Testing  

PubMed Central

Though changes in normal joint motions and loads (e.g., following anterior cruciate ligament injury) contribute to the development of knee osteoarthritis, the precise mechanism by which these changes induce osteoarthritis remains unknown. As a first step toward identifying this mechanism, this study evaluates computational wear simulations of a patellofemoral joint specimen wear tested on a knee simulator machine. A multi-body dynamic model of the specimen mounted in the simulator machine was constructed in commercial computer-aided engineering software. A custom elastic foundation contact model was used to calculate contact pressures and wear on the femoral and patellar articular surfaces using geometry created from laser scan and MR data. Two different wear simulation approaches were investigated – one that wore the surface geometries gradually over a sequence of 10 one-cycle dynamic simulations (termed the “progressive” approach), and one that wore the surface geometries abruptly using results from a single one-cycle dynamic simulation (termed the “non-progressive” approach). The progressive approach with laser scan geometry reproduced the experimentally measured wear depths and areas for both the femur and patella. The less costly non-progressive approach predicted deeper wear depths, especially on the patella, but had little influence on predicted wear areas. Use of MR data for creating the articular and subchondral bone geometry altered wear depth and area predictions by at most 13%. These results suggest that MR-derived geometry may be sufficient for simulating articular cartilage wear in vivo and that a progressive simulation approach may be needed for the patella and tibia since both remain in continuous contact with the femur. PMID:21453922

Li, Lingmin; Patil, Shantanu; Steklov, Nick; Bae, Won; Temple-Wong, Michele; D'Lima, Darryl D.; Sah, Robert L.; Fregly, Benjamin J.

2011-01-01

144

A Dominant-Negative Mutation of Mouse Lmx1b Causes Glaucoma and Is Semi-lethal via LBD1-Mediated Dimerisation  

PubMed Central

Mutations in the LIM-homeodomain transcription factor LMX1B cause nail-patella syndrome, an autosomal dominant pleiotrophic human disorder in which nail, patella and elbow dysplasia is associated with other skeletal abnormalities and variably nephropathy and glaucoma. It is thought to be a haploinsufficient disorder. Studies in the mouse have shown that during development Lmx1b controls limb dorsal-ventral patterning and is also required for kidney and eye development, midbrain-hindbrain boundary establishment and the specification of specific neuronal subtypes. Mice completely deficient for Lmx1b die at birth. In contrast to the situation in humans, heterozygous null mice do not have a mutant phenotype. Here we report a novel mouse mutant Icst, an N-ethyl-N-nitrosourea-induced missense substitution, V265D, in the homeodomain of LMX1B that abolishes DNA binding and thereby the ability to transactivate other genes. Although the homozygous phenotypic consequences of Icst and the null allele of Lmx1b are the same, heterozygous Icst elicits a phenotype whilst the null allele does not. Heterozygous Icst causes glaucomatous eye defects and is semi-lethal, probably due to kidney failure. We show that the null phenotype is rescued more effectively by an Lmx1b transgene than is Icst. Co-immunoprecipitation experiments show that both wild-type and Icst LMX1B are found in complexes with LIM domain binding protein 1 (LDB1), resulting in lower levels of functional LMX1B in Icst heterozygotes than null heterozygotes. We conclude that Icst is a dominant-negative allele of Lmx1b. These findings indicate a reassessment of whether nail-patella syndrome is always haploinsufficient. Furthermore, Icst is a rare example of a model of human glaucoma caused by mutation of the same gene in humans and mice. PMID:24809698

Cross, Sally H.; Macalinao, Danilo G.; McKie, Lisa; Rose, Lorraine; Kearney, Alison L.; Rainger, Joe; Thaung, Caroline; Keighren, Margaret; Jadeja, Shalini; West, Katrine; Kneeland, Stephen C.; Smith, Richard S.; Howell, Gareth R.; Young, Fiona; Robertson, Morag; van t' Hof, Rob; John, Simon W. M.; Jackson, Ian J.

2014-01-01

145

Hamstrings Loading Contributes to Lateral Patellofemoral Malalignment and Elevated Cartilage Pressures: An In Vitro Study  

PubMed Central

Background Hamstrings loading has previously been shown to increase tibiofemoral posterior translation and external rotation, which could contribute to patellofemoral malalignment and elevated patellofemoral pressures. The current study characterizes the influence of forces applied by the hamstrings on patellofemoral kinematics and the pressure applied to patellofemoral cartilage. Methods Ten knees were positioned at 40°, 60° and 80° of flexion in vitro, and loaded with 586 N applied through the quadriceps, with and without an additional 200 N applied through the hamstrings. Patellofemoral kinematics were characterized with magnetic sensors fixed to the patella and the femur, while the pressure applied to lateral and medial patellofemoral cartilage was measured with pressure sensors. A repeated measures ANOVA with three levels, combined with paired t-tests at each flexion angle, determined if loading the hamstrings significantly (P < 0.05) influenced the output. Findings Loading the hamstrings increased the average patellar flexion, lateral tilt and lateral shift by approximately 1°, 0.5° and 0.2 mm, respectively. Each increase was significant for at least two flexion angles. Loading the hamstrings increased the percentage of the total contact force applied to lateral cartilage by approximately 5%, which was significant at each flexion angle, and the maximum lateral pressure by approximately 0.3 MPa, which was significant at 40° and 60°. Interpretation The increased lateral shift and tilt of the patella caused by loading the hamstrings can contribute to lateral malalignment and shifts pressure toward the lateral facet of the patella, which could contribute to overloading of lateral cartilage. PMID:21543144

Elias, John J.; Kirkpatrick, Marcus S.; Saranathan, Archana; Mani, Saandeep; Smith, Laura G.; Tanaka, Miho J.

2011-01-01

146

Tibial Tuberosity Osteotomy for Patellofemoral Realignment Alters Tibiofemoral Kinematics  

PubMed Central

Background Tibial tuberosity realignment surgery is performed to improve patellofemoral alignment, but could also alter tibiofemoral kinematics. Hypothesis Following tuberosity realignment in the malaligned knee, the reoriented patella tendon will pull the tuberosity back toward the pre-operative position, thereby altering tibiofemoral kinematics. Study Design Controlled laboratory study. Methods Ten knees were tested at 40°, 60° and 80° of flexion in vitro. The knees were loaded with a quadriceps force of 586 N, with 200 N divided between the medial and lateral hamstrings. The position of the tuberosity was varied to represent lateral malalignment, with the tuberosity 5 mm lateral of the normal position, tuberosity medialization, with the tuberosity 5 mm medial of the normal position, and tuberosity anteromedialization, with the tuberosity 10 mm anterior of the medial position. Tibiofemoral kinematics were measured using magnetic sensors secured to the femur and tibia. A repeated measures ANOVA with a post-hoc Student-Newman-Keuls test was used to identify significant (p < 0.05) differences in the kinematic data between the tuberosity positions at each flexion angle. Results Medializing the tibial tuberosity primarily rotated the tibia externally, compared to the lateral malalignment condition. The largest average increase in external rotation was 13° at 40° of flexion, with the increase significant at each flexion angle. The varus orientation also increased significantly by an average of 1.5° at 40° and 80°. The tibia shifted significantly posteriorly at 40° and 60° by an average of 4 mm and 2 mm, respectively. Shifting the tuberosity from the medial to the anteromedial position translated the tibia significantly posteriorly by an average of 2 mm at 40°. Conclusions Following tibial tuberosity realignment in the malaligned knee, the altered orientation of the patella tendon alters tibiofemoral kinematics. Clinical Relevance The kinematic changes reduce the correction applied to the orientation of the patella tendon and could alter the pressure applied to tibiofemoral cartilage. PMID:21233407

Mani, Saandeep; Kirkpatrick, Marcus S.; Saranathan, Archana; Smith, Laura G.; Cosgarea, Andrew J.; Elias, John J.

2011-01-01

147

Patellar Cartilage: T2 Values and Morphologic Abnormalities at 3.0-T MR Imaging in Relation to Physical Activity in Asymptomatic Subjects from the Osteoarthritis Initiative1  

PubMed Central

Purpose: To study the interrelationship between patella cartilage T2 relaxation time, other knee abnormalities, and physical activity levels in asymptomatic subjects from the Osteoarthritis Initiative (OAI) incidence cohort. Materials and Methods: The study had institutional review board approval and was HIPAA compliant. One hundred twenty subjects from the OAI without knee pain (age, 45–55 years) and with risk factors for knee osteoarthritis (OA) were studied by using knee radiographs, 3.0-T knee magnetic resonance (MR) images (including intermediate-weighted fast spin-echo and T2 mapping sequences), and the Physical Activity Scale for the Elderly. MR images of the right knee were assessed by two musculoskeletal radiologists for the presence and grade of abnormalities. Segmentation of the patella cartilage was performed, and T2 maps were generated. Statistical significance was determined by using analysis of variance, ?2 analysis, correlation coefficient tests, the Cohen ?, and a multiple linear regression model. Results: Cartilage lesions were found in 95 (79.0%) of 120 knees, and meniscal lesions were found in 54 (45%) of 120 knees. A significant correlation between patella cartilage T2 values and the severity and grade of cartilage (P = .0025) and meniscus (P = .0067) lesions was demonstrated. Subjects with high activity levels had significantly higher prevalence and grade of abnormalities and higher T2 values (48.7 msec ±4.35 vs 45.8 msec ±3.93; P < .001) than did subjects with low activity levels. Conclusion: Middle-aged asymptomatic individuals with risk factors for knee OA had a high prevalence of cartilage and meniscus knee lesions. Physically active individuals had more knee abnormalities and higher patellar T2 values. Additional studies will be needed to determine causality. © RSNA, 2010 PMID:20019141

Liebl, Hans; Krug, Roland; Lane, Nancy E.; Nevitt, Michael C.; Lynch, John; McCulloch, Charles E.; Link, Thomas M.

2010-01-01

148

Biochemical (T2, T2* and magnetisation transfer ratio) MRI of knee cartilage: feasibility at ultra-high field (7T) compared with high field (3T) strength  

Microsoft Academic Search

Objective  This study compares the performance and the reproducibility of quantitative T2, T2* and the magnetisation transfer ratio (MTR)\\u000a of articular cartilage at 7T and 3T.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Axial MRI of the patella was performed in 17 knees of healthy volunteers (25.8?±?5.7 years) at 3T and 7T using a comparable\\u000a surface coil and whole-body MR systems from the same vendor, side-by-side. Thirteen knee joints

Goetz H. Welsch; Sebastian Apprich; Stefan Zbyn; Tallal C. Mamisch; Vladimir Mlynarik; Klaus Scheffler; Oliver Bieri; Siegfried Trattnig

2011-01-01

149

Radiologic study of patellar height in Osgood-Schlatter disease.  

PubMed

There are contradictory reports regarding patellar position in the Osgood-Schlatter disease. We present a prospective statistical study of 17 patients with Osgood-Schlatter disease and 12 adolescents without anterior knee pain. The Caton-Deschamps index was assessed on strictly the lateral radiograph of the knee. The findings indicate a strong association between Osgood-Schlatter disease and patella alta. This increase in patellar height would require an increase in the force needed from the quadriceps to achieve full extension. This mechanism could be responsible for the apophyseal lesion. PMID:8989704

Aparicio, G; Abril, J C; Calvo, E; Alvarez, L

1997-01-01

150

Musculoskeletal injuries in adolescents.  

PubMed

This article reviews the anatomy of the physis and the most common classification of injuries or fractures through the physis. The common apophyseal injuries of Osgood-Schlatter, Severs disease and iliac apophysitis, are reviewed in addition to a review of the most common osteochondritides, including Panner's disease and Osteochondritis Dessicans of the femur and talus. An understanding of these is key to diagnosis and treatment of adolescent musculoskeletal injuries. This article also reviews slipped capital femoral epiphysis, little leaguer's elbow, anterior cruciate and collateral ligament injuries, patella problems, ankle sprains and several common fractures in children. PMID:9469924

Kaeding, C C; Whitehead, R

1998-03-01

151

Lateral Patellofemoral Ligament Reconstruction Using a Quadriceps Tendon Graft  

PubMed Central

Medial patellar subluxation (MPS) is normally described after a lateral retinacular release. However, isolated MPS in the absence of a previous lateral release does occur. This type of patellar instability is often overlooked, and a high index of suspicion is needed for appropriate diagnosis and treatment. This report describes a technique developed in response to episodes of isolated MPS. The technique uses a partial-thickness graft from the quadriceps tendon to reconstruct the lateral patellofemoral ligament and provide stability to the lateral side of the patella. PMID:25264506

Saper, Michael G.; Shneider, David A.

2014-01-01

152

Taping for knee osteoarthritis.  

PubMed

Taping can be used to reduce pain in knee osteoarthritis. There are different methods of taping, but the common effect is to exert a medially directed force on the patella to increase the patellofemoral contact area, thereby decreasing joint stress and reducing pain. Taping can be performed by a physiotherapist, but self taping can be taught, which enhances self management. Taping for knee osteoarthritis has National Health and Medical Research Council (NHMRC) Level I evidence of efficacy for pain relief and is associated with negligible adverse effects that generally include minor skin irritation. PMID:24130976

2013-10-01

153

Surgical approaches in total knee arthroplasty  

PubMed Central

Total knee replacement surgery begins with correct planning of both the incision and the exposure of the joint. Indeed, these are factors that are just as crucial to an optimal outcome as choosing the right implant, positioning the components, and balancing the ligaments. While it is true that the standard incision and arthrotomy (with which we are most familiar) will, in most primary implant cases, provide adequate joint exposure, it is also true that cases characterized by certain conditions, such as previous cutaneous incisions, a stiff knee or patella baja, present specific skin and exposure problems that need to be recognized, planned for and overcome.

SANNA, MARCO; SANNA, CRISTINA; CAPUTO, FRANCESCO; PIU, GIUSEPPE; SALVI, MASSIMILIANO

2013-01-01

154

Intracellular coagulation inhibits the extraction of proteins from Prochloron  

NASA Technical Reports Server (NTRS)

Protein extraction from the prokaryotic alga Prochloron LP (isolated from the ascidian host Lissoclinum patella) was complicated by an irreversible loss of cell fragility in the isolated algae. Accompanying this phenomenon, which is termed intracellular coagulation, was a redistribution of thylakoids around the cell periphery, a loss of photosynthetic O2 production, and a drastic decrease in the extractability of cell proteins. Procedures are described for the successful preparation and transport of cell extracts yielding the enzymes glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase as well as other soluble proteins.

Fall, R.; Lewin, R. A.; Fall, L. R.

1983-01-01

155

Two cases of surgically treated feline patellar fractures.  

PubMed

A transverse patellar fracture in a six-month-old cat was successfully treated by figure-of-eight dorsal wiring of the patella. A longitudinal patellar fracture with luxation of a large medial fragment in a 2.5-year-old cat was treated by lateral marginal patellectomy with a positive outcome. While adding material to the few veterinary reports in that species, in this brief communication, the authors discuss the aetiology, diagnosis, and the treatment of the presented cases with regards to findings in previously published feline cases. PMID:18545720

Guillaumot, P; Scotti, S; Carozzo, C; Bouvy, B; Genevois, J-P

2008-01-01

156

Patellar resurfacing in total knee arthroplasty for osteoarthritis: a meta-analysis  

Microsoft Academic Search

Purpose  Whether to resurface the patella during a primary total knee arthroplasty remains a controversial issue. The aim of this study\\u000a was to determine the advantages and disadvantages of patellar resurfacing during total knee arthroplasty for osteoarthritis\\u000a through an evaluation of the current literature.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  A meta-analysis of randomized controlled trials comparing patellar resurfacing with nonresurfacing during total knee arthroplasties\\u000a was performed.

Yonghui FuGuangbin; Guangbin Wang; Qin Fu

157

Revision Surgery for Patellofemoral Problems: Should We Always Resurface?  

Microsoft Academic Search

Background  Routine patellar resurfacing performed at the time of knee arthroplasty is controversial, with some evidence of utility in\\u000a both TKA (tricompartmental) and bicompartmental knee arthroplasty. However, whether one approach results in better implant\\u000a survival remains unclear.\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/purposes  We asked whether (1) routine patellar resurfacing in TKAs resulted in lower cumulative revision rates compared to bicompartmental\\u000a knee arthroplasties, (2) patella-friendly implants resulted

Todd C. Johnson; Penny J. Tatman; Susan Mehle; Terence J. Gioe

158

The Gritti-Stokes amputation in ischaemia: a review of 134 cases.  

PubMed

The results of 134 Gritti-Stokes amputations for ischaemia are presented. The mortality rate was 11% and healing occurred in 88%, reaffirming the good results already reported for this operation. The long term results are reviewed in an attempt to decide whether the most frequently cited criticisms of this procedure are justified. Stump pain and mobility of the patella were not major problems. The difficulties in fitting a suitable prosthesis are discussed and attention is drawn to the advantages of a new prosthesis that has been developed for this amputation. PMID:626827

Doran, J; Hopkinson, B R; Makin, G S

1978-02-01

159

Primary total knee replacement: a comparison of a nationally agreed guide to best practice and current surgical technique as determined by the North West Regional Arthroplasty Register.  

PubMed Central

INTRODUCTION: In 1999, a statement of best practice in primary total hip replacement was approved by the Council of the British Orthopaedic Association (BOA) and by the British Association for Surgery of the Knee (BASK) to provide a basis for regional and national auditable standards: we have compared practice in the North West of England to this document to ascertain adherence to this guide to best practice. MATERIALS AND METHODS: A direct comparison of data held on the North West Hip Arthroplasty Register for 2001/2002 and BASK/BOA guidelines was performed. 86 surgeons from 26 hospitals were included in the study. RESULTS: A mean of 93.3% of operations were performed in the surgeon's usual theatre. All of these theatres had vertical laminar air flow systems. 42.2% of respondents routinely used exhaust suits and 68.1% of respondents routinely used impermeable disposable gowns. All surgeons use some form of anti-thromboembolic prophylaxis; 66.2% use a combination of both mechanical and chemical means. All surgeons used antibiotic prophylaxis. The most popular choice of antibiotic was a cephalosporin. 93.7% of surgeons routinely use antibiotic-loaded cement. The PFC and Kinemax prostheses were the most commonly used prostheses. Interestingly, 97.7% of all first-choice implants were cemented. Only 2 surgeons used uncemented total knee replacement. 69.8% of surgeons used a posterior cruciate retaining design. A midline longitudinal skin incision is used by 87.2% of surgeons, a medial longitudinal skin incision by 7.0% and a lateral longitudinal skin incision by 5.8% of surgeons. A medial parapatellar capsular incision is preferred by 91.9% with the remainder using mid vastus or trivector retaining capsulotomy. Closure of capsulotomies is performed in flexion by 65.1% and in extension by 34.9%. In patients with osteoarthritis, 38.4% routinely resurfaced the patella, 34.9% never resurfaced the patella and 26.7% selectively resurfaced. This was in direct contrast to practice for patients with rheumatoid arthritis in whom 66.3% routinely resurfaced the patella, 22.1% never resurfaced the patella and 11.6% selectively resurfaced. DISCUSSION AND CONCLUSIONS: This study has demonstrated variation of practice in hip arthroplasty across the North West region and significant divergence from the BASK/BOA statement of best practice. The introduction of a properly funded national arthroplasty register will surely help to clarify the effect of such diverse practice on patient outcome. PMID:15826423

Malik, M. H. A.; Chougle, A.; Pradhan, N.; Gambhir, A. K.; Porter, M. L.

2005-01-01

160

“A 40-year-old female with painless, slow growing prepatellar mass”?  

PubMed Central

A 40-year-old woman from India presented with a mass in the front of her left knee which had been present for 8 months. Local examination revealed a globular mass of approximate size 5 cm × 4 cm × 4 cm in front of the lower pole of left patella. The patient was investigated with imaging studies and laboratory tests. Plain radiograph of the chest was normal. In addition, contrast enhanced Magnetic Resonance Imaging (MRI) of the left knee was performed. Based on the history, physical examination, laboratory and imaging studies, what is the differential diagnosis?

Arora, Sumit; Batra, Sahil; Rao, Seema; Maini, Lalit; Gautam, V.K.

2014-01-01

161

Photosymbiotic ascidians from Pari Island (Thousand Islands, Indonesia)  

PubMed Central

Abstract Photosymbiotic ascidian fauna were surveyed in the subtidal zone off Pari Island in the Thousand Islands (Java Sea, Indonesia). Nine species were recorded: Didemnum molle, Trididemnum miniatum, Lissoclinum patella, L. punctatum, L. timorense, Diplosoma gumavirens, D. simile, D. simileguwa, and D. virens. All of these species have been previously recorded in the Ryukyu Archipelago, Japan. Diplosoma gumavirens and D. simileguwa were originally described from the Ryukyu Archipelago in 2009 and 2005, respectively, and all of the observed species are potentially widely distributed in Indo–West Pacific coral reefs. PMID:25061385

Hirose, Euichi; Iskandar, Budhi Hascaryo; Wardiatno, Yusli

2014-01-01

162

A joint-constraint model-based system for reconstructing total knee motion.  

PubMed

Comprehending knee motion is an essential requirement for studying the causes of knee disorders. In this paper, we propose a new 2-D-3-D registration system based on joint-constraint model for reconstructing total knee motion. The proposed model that contains bone geometries and an articulated joint mechanism is first constructed from multipostural magnetic resonance volumetric images. Then, the bone segments of the model are hierarchically registered to each frame of the given single-plane fluoroscopic video that records the knee activity. The bone posture is iteratively optimized using a modified chamfer matching algorithm to yield the simulated radiograph which is the best fit to the underlying fluoroscopic image. Unlike conventional registration methods computing posture parameters for each bone independently, the proposed femorotibial and patellofemoral joint models properly maintain the articulations between femur, tibia, and patella during the registration processes. As a result, we can obtain a sequence of registered knee postures showing smooth and reasonable physiologic patterns of motion. The proposed system also provides joint-space interpolation to densely generate intermediate postures for motion animation. The effectiveness of the proposed method was validated by computer simulation, animal cadaver, and in vivo knee testing. The mean target registration errors for femur, tibia, and patella were less than 1.5 mm. In particular, small out-of-plane registration errors [less than 1 mm (translation) and 2° (rotation)] were achieved in animal cadaver assessments. PMID:23963191

Hsin-Chen Chen; Chia-Hsing Wu; Chien-Kuo Wang; Chii-Jeng Lin; Yung-Nien Sun

2014-01-01

163

Progression of Gene Expression Changes following a Mechanical Injury to Articular Cartilage as a Model of Early Stage Osteoarthritis  

PubMed Central

An impact injury model of early stage osteoarthritis (OA) progression was developed using a mechanical insult to an articular cartilage surface to evaluate differential gene expression changes over time and treatment. Porcine patellae with intact cartilage surfaces were randomized to one of three treatments: nonimpacted control, axial impaction (2000?N), or a shear impaction (500?N axial, with tangential displacement to induce shear forces). After impact, the patellae were returned to culture for 0, 3, 7, or 14 days. At the appropriate time point, RNA was extracted from full-thickness cartilage slices at the impact site. Quantitative real-time PCR was used to evaluate differential gene expression for 18 OA related genes from four categories: cartilage matrix, degradative enzymes and inhibitors, inflammatory response and signaling, and cell apoptosis. The shear impacted specimens were compared to the axial impacted specimens and showed that shear specimens more highly expressed type I collagen (Col1a1) at the early time points. In addition, there was generally elevated expression of degradative enzymes, inflammatory response genes, and apoptosis markers at the early time points. These changes suggest that the more physiologically relevant shear loading may initially be more damaging to the cartilage and induces more repair efforts after loading. PMID:25478225

McCulloch, R. S.; Ashwell, M. S.; Maltecca, C.; O'Nan, A. T.; Mente, P. L.

2014-01-01

164

[Overuse injury syndromes of the knee].  

PubMed

Overuse injuries are frequent in the knee joint. The reason for this is that the knee joint is engaged in all sports activities. Furthermore, the joint area has numerous attachment points for muscles and tendons and numerous bursae. Another reason is that the specific joint between the patella and femur (patellofemoral joint) constitutes a part of the knee joint. Speaking in general terms, all overuse injuries in the knee joint can be divided in four groups according to the aspect: anterior aspect--patellofemoral pain syndrome, patellar tendinitis (jumper's knee), Osgood-Schlatter disease, Sinding Larson Johanson disease, stress fracture of the patella, fat pad syndrome; medial aspect--plica syndrome, semimembranosus tendinitis, pes anserinus tendinitis (bursitis), breaststroker's knee, medial retinaculitis; lateral aspect--Iliotibial band friction syndrome (runner's knee), Popliteal Tendinitis, Bicipital tendinitis; posterior aspect--fabellitis, medial gastrocnemius strain. There are numerous possible reasons for pain caused by overuse injuries around the knee joint, but two are the most frequent: patellar tendinitis (jumper's knee) and Iliotibial band friction syndrome (runner's knee). This paper gives a brief overview of overuse injuries of the knee joint including their definition, anatomy, aetiology, clinical symptoms and signs, and non-operative and surgical treatment. PMID:11831126

Pe?ina, M; Bojani?, I; Haspl, M

2001-12-01

165

18S ribosomal DNA sequences provide insight into the phylogeny of patellogastropod limpets (Mollusca: Gastropoda).  

PubMed

To investigate the phylogeny of Patellogastropoda, the complete 18S rDNA sequences of nine patellogastropod limpets Cymbula canescens (Gmelin, 1791), Helcion dunkeri (Krauss, 1848), Patella rustica Linnaeus, 1758, Cellana toreuma (Reeve, 1855), Cellana nigrolineata (Reeve, 1854), Nacella magellanica Gmelin, 1791, Nipponacmea concinna (Lischke, 1870), Niveotectura pallida (Gould, 1859), and Lottia dorsuosa Gould, 1859 were determined. These sequences were then analyzed along with the published 18S rDNA sequences of 35 gastropods, one bivalve, and one chiton species. Phylogenetic trees were constructed by maximum parsimony, maximum likelihood, and Bayesian inference. The results of our 18S rDNA sequence analysis strongly support the monophyly of Patellogastropoda and the existence of three subgroups. Of these, two subgroups, the Patelloidea and Acmaeoidea, are closely related, with branching patterns that can be summarized as [(Cymbula + Helcion) + Patella] and [(Nipponacmea + Lottia) + Niveotectura]. The remaining subgroup, Nacelloidea, emerges as basal and paraphyletic, while its genus Cellana is monophyletic. Our analysis also indicates that the Patellogastropoda have a sister relationship with the order Cocculiniformia within the Gastropoda. PMID:17464213

Yoon, Sook Hee; Kim, Won

2007-02-28

166

Intoeing--fact, fiction and opinion.  

PubMed

Intoeing in children is a common cause of parental concern. A normal neurologic examination and normal height and weight for age help the physician exclude most associated skeletal dysplasias, and neuromuscular or metabolic diseases. Three causes of intoeing affect otherwise normal newborns and infants. Metatarsus adductus is the diagnosis if a "C" shaped curve, rather than a straight border, is present on the lateral aspect of the foot. About 90 percent of cases resolve by one year of age. Internal tibial torsion, although a normal finding in the newborn, is usually a matter of concern at walking age. When the child is walking or standing, the patella can be seen to point forward, with the foot pointing inward. Children with excessive femoral anteversion, the most common cause of intoeing, walk or stand with both patella and feet pointing inward. Nonsurgical treatment, with the exception of casting in children with metatarsus adductus, has not been shown to be effective. Osteotomy, the only effective treatment for rotational abnormalities of the femur and tibia, has high complication rates and should not be considered until the patient is eight to 10 years of age. Since disability from intoeing is extremely rare and most cases resolve spontaneously, observation and parental education are important from the time of diagnosis. PMID:7942424

Dietz, F R

1994-11-01

167

Photoadaptation and protection against active forms of oxygen in the symbiotic procaryote Prochloron sp. and its ascidian host  

SciTech Connect

Superoxide dismutase, ascorbate, peroxidase, and catalase activities were studied in the symbiotic photosynthetic procaryote Prochloron sp. and its ascidian host Lissoclinum patella. The protein-specific activities of these antioxidant enzymes in the Prochloron sp. and L. patella collected at different depths from the Great Barrier Reef, Australia, were directly proportional to irradiance, whereas the pigment concentrations in the Prochloron sp. were inversely proportional to irradiance. The presence of a cyanide-sensitive superoxide dismutase, presumably a Cu-An metalloprotein, in the Prochloron sp. extends the possible phylogenetic distribution of this protein. The concentration of UV-absorbing mycosporine-like amino acids in inversely proportional to irradiance in both the host and symbiont, suggesting that these compounds may not provide sufficient protection against UV radiation in high-irradiance environments. The significant differences in the specific activities of these antioxidant enzymes, cellular photosynthetic pigment concentrations, and UV-absorbing compounds from high- and low-irradiance habitats constitute an adaptive response to different photic environments. These photoadaptive responses are essential to prevent inhibition of photosynthesis by high fluxes of visible and UV radiation.

Lesser, M.P.; Stochaj, W.R. (Univ. of Maine, Orono (USA))

1990-06-01

168

Effect of cervicolabyrinthine impulsation on the spinal reflex apparatus  

NASA Technical Reports Server (NTRS)

In view of the fact that the convergence effect of vestibular impulsation may both stimulate and inhibit intra and intersystemic coordination of physiological processes, an attempt was made to define the physiological effect on the spinal reflex apparatus of the convergence of cervicolabyrinthine impulsation on a model of the unconditioned motor reflex as a mechanism of the common final pathway conditioning the formation and realization of a focused beneficial result of human motor activities. More than 100 persons subjected to rolling effect and angular acceleration during complexly coordinated muscular loading were divided according to typical variants of the functional structure of the patella reflex in an experiment requiring 30 rapid counterclockwise head revolutions at 2/sec with synchronous recording of a 20 item series of patella reflex acts. A knee jerk coefficient was used in calculations. In 85 percent of the cases 2 patellar reflexograms show typical braking and release of knee reflex and 1 shows an extreme local variant. The diagnostic and prognostic value of these tests is suggested for determining adaptive possibilities of functional systems in respect to acceleration and proprioceptive stimuli.

Yarotskiy, A. I.

1980-01-01

169

Evidence Based Conservative Management of Patello-femoral Syndrome  

PubMed Central

Patellofemoral pain syndrome (PFPS) is defined as pain surrounding the patella when sitting with bent knees for prolonged periods of time or when performing activities like ascending or descending stairs, squatting or athletic activities. Patella dislocation is not included in PFPS. This review analyzes the evidence based conservative management of PFPS. A Cochrane Library search related to PFPS was performed until 18 January 2014. The key words were: patellofemoral pain syndrome. Eight papers were found, of which three were reviewed because they were focused on the topic of the article. We also searched the PubMed using the following keywords: evidence based conservative management of patellofemoral pain syndrome. Twelve articles were found, of which seven were reviewed because they were focused on the topic of the article. Overall ten articles were analyzed. Different treatments can be tried for PFPS, including pharmacotherapy, therapeutic ultrasound, exercise therapy, and taping and braces. Non-steroidal anti-inflammatory drugs (NSAIDs) may reduce pain in the short term, but pain does not improve after three months. Therapeutic ultrasound appears not to have a clinically important effect on pain relief for patients with PFPS. The evidence that exercise therapy is more effective in treating PFPS than no exercise is limited with respect to pain reduction, and conflicting with respect to functional improvement. No significant difference has been found between taping and non-taping. The role of knee braces is still controversial. More well-designed studies are needed. PMID:25207305

Rodriguez-Merchan, E. Carlos

2014-01-01

170

Description of patellar movement by 3D parameters obtained from dynamic CT acquisition  

NASA Astrophysics Data System (ADS)

The patellofemoral joint is critical in the biomechanics of the knee. The patellofemoral instability is one condition that generates pain, functional impairment and often requires surgery as part of orthopedic treatment. The analysis of the patellofemoral dynamics has been performed by several medical image modalities. The clinical parameters assessed are mainly based on 2D measurements, such as the patellar tilt angle and the lateral shift among others. Besides, the acquisition protocols are mostly performed with the leg laid static at fixed angles. The use of helical multi slice CT scanner can allow the capture and display of the joint's movement performed actively by the patient. However, the orthopedic applications of this scanner have not yet been standardized or widespread. In this work we present a method to evaluate the biomechanics of the patellofemoral joint during active contraction using multi slice CT images. This approach can greatly improve the analysis of patellar instability by displaying the physiology during muscle contraction. The movement was evaluated by computing its 3D displacements and rotations from different knee angles. The first processing step registered the images in both angles based on the femu?s position. The transformation matrix of the patella from the images was then calculated, which provided the rotations and translations performed by the patella from its position in the first image to its position in the second image. Analysis of these parameters for all frames provided real 3D information about the patellar displacement.

de Sá Rebelo, Marina; Moreno, Ramon Alfredo; Gobbi, Riccardo Gomes; Camanho, Gilberto Luis; de Ávila, Luiz Francisco Rodrigues; Demange, Marco Kawamura; Pecora, Jose Ricardo; Gutierrez, Marco Antonio

2014-03-01

171

Atlas-Based Knee Cartilage Assessment  

PubMed Central

Magnetic resonance imaging analysis of knee cartilage properties at corresponding anatomic locations could be a valuable tool in studies of knee osteoarthritis by enabling accurate comparisons at practically any region. A technique of this kind is presented in this study. The proposed technique is based on gray-level bone matching using affine transformations and free-form deformations thus eliminating the need of bone segmentations and landmark matching. Sixteen subjects of the osteoarthritis initiative with knee osteoarthritis (10 from baseline; 6 from 24-month follow-up) were included in this study. Baseline subjects were used to create a gray-level atlas of the patella with its corresponding mean cartilage thickness and T2 maps. Follow-up subjects were used to validate atlas-based point-to-point cartilage comparisons. All registrations were qualitatively evaluated with fused gray-level images of registered patellas. Quantitative evaluation was performed based on mean values of minimum Euclidean distances between matched bone-cartilage interfaces. A mean distance of 0.554 mm was obtained between the subjects used to build the atlas, and a mean distance of 0.633 mm was found between the atlas and validation subjects. The technique can be applied to other anatomical regions and with other cartilage measures. Qualitative and quantitative results demonstrate the accuracy of the technique and warrant its application in larger cross-sectional and longitudinal studies of osteoarthritis. PMID:21773988

Carballido-Gamio, Julio; Majumdar, Sharmila

2012-01-01

172

Barriers to Gene Flow in the Marine Environment: Insights from Two Common Intertidal Limpet Species of the Atlantic and Mediterranean  

PubMed Central

Knowledge of the scale of dispersal and the mechanisms governing gene flow in marine environments remains fragmentary despite being essential for understanding evolution of marine biota and to design management plans. We use the limpets Patella ulyssiponensis and Patella rustica as models for identifying factors affecting gene flow in marine organisms across the North-East Atlantic and the Mediterranean Sea. A set of allozyme loci and a fragment of the mitochondrial gene cytochrome C oxidase subunit I were screened for genetic variation through starch gel electrophoresis and DNA sequencing, respectively. An approach combining clustering algorithms with clinal analyses was used to test for the existence of barriers to gene flow and estimate their geographic location and abruptness. Sharp breaks in the genetic composition of individuals were observed in the transitions between the Atlantic and the Mediterranean and across southern Italian shores. An additional break within the Atlantic cluster separates samples from the Alboran Sea and Atlantic African shores from those of the Iberian Atlantic shores. The geographic congruence of the genetic breaks detected in these two limpet species strongly supports the existence of transpecific barriers to gene flow in the Mediterranean Sea and Northeastern Atlantic. This leads to testable hypotheses regarding factors restricting gene flow across the study area. PMID:23239977

Sá-Pinto, Alexandra; Branco, Madalena S.; Alexandrino, Paulo B.; Fontaine, Michaël C.; Baird, Stuart J. E.

2012-01-01

173

Biology and augmentation of tendon-bone insertion repair  

PubMed Central

Surgical reattachment of tendon and bone such as in rotator cuff repair, patellar-patella tendon repair and anterior cruciate ligament (ACL) reconstruction often fails due to the failure of regeneration of the specialized tissue ("enthesis") which connects tendon to bone. Tendon-to-bone healing taking place between inhomogenous tissues is a slow process compared to healing within homogenous tissue, such as tendon to tendon or bone to bone healing. Therefore special attention must be paid to augment tendon to bone insertion (TBI) healing. Apart from surgical fixation, biological and biophysical interventions have been studied aiming at regeneration of TBI healing complex, especially the regeneration of interpositioned fibrocartilage and new bone at the healing junction. This paper described the biology and the factors influencing TBI healing using patella-patellar tendon (PPT) healing and tendon graft to bone tunnel healing in ACL reconstruction as examples. Recent development in the improvement of TBI healing and directions for future studies were also reviewed and discussed. PMID:20727196

2010-01-01

174

[External patello-tibial transfixation. I: Indications and technique].  

PubMed

Patello-tibial transfixation using the MPT-fixator is a new kind of external fixation. The device works biomechanically transferring the quadriceps tension forces from the patella to the lower leg and converting them into extension of the knee. The fixator can be applied in two different configurations. When performing configuration A, a Steinmann pin with a central thread is transversely placed through the patella and proximal tibia. Both pins are joined to connecting rods. Configuration B differs from type A in that a Schanz screw is inserted from anterior to posterior through the proximal tibia. The frame construction is achieved by fastening the tibial-sided Steinmann pin with a special clamp at the Schanz screw. Patello-tibial transfixation is indicated in the repair of fresh extensor mechanism disruption and reconstruction of neglected rupture of the patellar tendon. The technique provides a secure protection of the repair and reconstruction against mechanical overloading during the healing period. It enables immediate functional after-treatment and mobilization with early full weight bearing. PMID:9132951

Gotzen, L; Ishaque, B; Morgenthal, F; Petermann, J

1997-01-01

175

Atlas-based knee cartilage assessment.  

PubMed

Magnetic resonance imaging analysis of knee cartilage properties at corresponding anatomic locations could be a valuable tool in studies of knee osteoarthritis by enabling accurate comparisons at practically any region. A technique of this kind is presented in this study. The proposed technique is based on gray-level bone matching using affine transformations and free-form deformations thus eliminating the need of bone segmentations and landmark matching. Sixteen subjects of the osteoarthritis initiative with knee osteoarthritis (10 from baseline; 6 from 24-month follow-up) were included in this study. Baseline subjects were used to create a gray-level atlas of the patella with its corresponding mean cartilage thickness and T2 maps. Follow-up subjects were used to validate atlas-based point-to-point cartilage comparisons. All registrations were qualitatively evaluated with fused gray-level images of registered patellas. Quantitative evaluation was performed based on mean values of minimum Euclidean distances between matched bone-cartilage interfaces. A mean distance of 0.554 mm was obtained between the subjects used to build the atlas, and a mean distance of 0.633 mm was found between the atlas and validation subjects. The technique can be applied to other anatomical regions and with other cartilage measures. Qualitative and quantitative results demonstrate the accuracy of the technique and warrant its application in larger cross-sectional and longitudinal studies of osteoarthritis. PMID:21773988

Carballido-Gamio, Julio; Majumdar, Sharmila

2011-08-01

176

Photoadaptation and Protection against Active Forms of Oxygen in the Symbiotic Procaryote Prochloron sp. and Its Ascidian Host  

PubMed Central

Superoxide dismutase, ascorbate peroxidase, and catalase activities were studied in the symbiotic photosynthetic procaryote Prochloron sp. and its ascidian host Lissoclinum patella. The protein-specific activities of these antioxidant enzymes in the Prochloron sp. and L. patella collected at different depths from the Great Barrier Reef, Australia, were directly proportional to irradiance, whereas the pigment concentrations in the Prochloron sp. were inversely proportional to irradiance. The presence of a cyanide-sensitive superoxide dismutase, presumably a Cu-Zn metalloprotein, in the Prochloron sp. extends the possible phylogenetic distribution of this protein. The concentration of UV-absorbing mycosporine-like amino acids is inversely proportional to irradiance in both the host and symbiont, suggesting that these compounds may not provide sufficient protection against UV radiation in high-irradiance environments. The significant differences in the specific activities of these antioxidant enzymes, cellular photosynthetic pigment concentrations, and UV-absorbing compounds from high- and low-irradiance habitats constitute an adaptive response to different photic environments. These photoadaptive responses are essential to prevent inhibition of photosynthesis by high fluxes of visible and UV radiation. PMID:16348202

Lesser, Michael P.; Stochaj, Wayne R.

1990-01-01

177

Arthritis in a Glyptodont (Mammalia, Xenarthra, Cingulata)  

PubMed Central

Arthritic lesions have been frequently diagnosed in the fossil record, with spondyloarthropathy (a type of erosive and pan-mammalian arthritis) being one of the most common types described to date for mammals, though not restricted to this group. Here, we identify spondyloarthropathy in fossil bones from the late Pleistocene in Brazil assignable to a large glyptodont individual. Bone erosions in the peripheral joints (viz., the ulna, radius, left femur and tibiae-fibulae) associated with osteosclerosis allow the diagnosis of spondyloarthropathy. The presence of osteophytes in seven bones of the forelimbs (viz., the ulna and radius) and hind limbs (viz., the tibiae-fibulae, left femur and patellae) and a subchondral cyst in one element (viz., the left femur) indicate secondary osteoarthritis. A calcified deposition on the articular surface of the left patella indicates the presence of calcium pyrophosphate deposition disease, which, like the observed osteoarthritic alterations, likely represents a complication of spondyloarthropathy. This is the first report of spondyloarthropathy for xenarthrans. PMID:24551126

Barbosa, Fernando Henrique de Souza; Porpino, Kleberson de Oliveira; Fragoso, Ana Bernadete Lima; Oliveira, Edison Vicente

2014-01-01

178

Using Real-Time MRI to Quantify Altered Joint Kinematics in Subjects with Patellofemoral Pain and to Evaluate the Effects of a Patellar Brace or Sleeve on Joint Motion  

PubMed Central

Abnormal patellofemoral joint motion is a possible cause of patellofemoral pain, and patellar braces are thought to alleviate pain by restoring normal joint kinematics. We evaluated whether females with patellofemoral pain exhibit abnormal patellofemoral joint kinematics during dynamic, weight-bearing knee extension and assessed the effects of knee braces on patellofemoral motion. Real-time magnetic resonance (MR) images of the patellofemoral joints of 36 female volunteers (13 pain-free controls, 23 patellofemoral pain) were acquired during weight-bearing knee extension. Pain subjects were also imaged while wearing a patellar-stabilizing brace and a patellar sleeve. We measured axial-plane kinematics from the images. Females with patellofemoral pain exhibited increased lateral translation of the patella for knee flexion angles between 0° and 50° (p = 0.03), and increased lateral tilt for knee flexion angles between 0° and 20° (p = 0.04). The brace and sleeve reduced the lateral translation of the patella; however, the brace reduced lateral displacement more than the sleeve (p = 0.006). The brace reduced patellar tilt near full extension (p = 0.001), while the sleeve had no effect on patellar tilt. Our results indicate that some subjects with patellofemoral pain exhibit abnormal weight-bearing joint kinematics and that braces may be effective in reducing patellar maltracking in these subjects. PMID:18985690

Draper, Christine E.; Besier, Thor F.; Santos, Juan M.; Jennings, Fabio; Fredericson, Michael; Gold, Garry E.; Beaupre, Gary S.; Delp, Scott L.

2010-01-01

179

Supracondylar femoral extension osteotomy and patellar tendon advancement in the management of persistent crouch gait in cerebral palsy  

PubMed Central

Background: Severe crouch gait in adolescent cerebral palsy is a difficult problem to manage. The patients develop loading of patellofemoral joint, leading to pain, gait deviation, excessive energy expenditure and progressive loss of function. Patella alta and avulsion of patella are the other complications. Different treatment options have been described in the literature to deal with this difficult problem. We evaluated outcome of supracondylar femoral extension osteotomy (SCFEO) and patellar tendon advancement (PTA) in the treatment of crouch gait in patients with cerebral palsy. Materials and Methods: Fourteen adolescents with crouch gait were operated by SCFEO and PTA. All subjects were evaluated pre and postoperatively. Clinical, radiographic, observational gait analysis and functional measures were included to assess the changes in knee function. Results: Cases were followed up to 3 years. The patients walked with increased knee extension and improvement in quadriceps muscle strength. Knee pain was decreased and improvements in functional mobility and radiologic improvement were found. Conclusion: SCFEO and PTA for adolescent crouch gait is effective in improving knee extensor strength, reducing knee pain and improving function. PMID:22448063

Das, Sakti Prasad; Pradhan, Sudhakar; Ganesh, Shankar; Sahu, Pabitra Kumar; Mohanty, Ram Narayan; Das, Sanjay Kumar

2012-01-01

180

Anatomical reconstruction of the patellar tendon using the fascia lata attached to the iliac bone following resection for soft tissue sarcoma: A case report  

PubMed Central

A new reconstruction of the patellar tendon was performed in a 43-year-old patient who lost tendon and tibial tuberosity after a wide tumor resection for low-grade myofibroblastic sarcoma of the parapatellar tendon. In this technique, the patellar tendon was anatomically reconstructed using a fascia lata attached to the iliac bone. The iliac bone was fixed to the tibial bony trough with absorbable screws, and the fascia lata was fashioned into three branches: the central branch was folded through the tunnel in the patella, and the medial and lateral branches were tagged to the medial and lateral retinaculum, respectively, around the patella. The skin defect was covered by the bilateral head of the gastrocnemius flap and a split-thickness skin graft. At the 3-year follow-up, the active range of motion of the knee joint was 0 to 110 degrees. The functional result according to the Musculoskeletal Tumor Society scoring system was 97%. Radiographs showed that the grafted bone was united well to the tibial bone, and the grafted fascia was confirmed as a dark band on MRI. There was no evidence of disease and no complaint of the donor site. This procedure allows for the reconstruction of the patellar tendon in the original location. To our knowledge, this reconstructive procedure of the patellar tendon using the fascia lata attached to the iliac bone has never been reported in English literature. PMID:22651248

Yoshida, Masahiro; Miyamoto, Kentaro

2012-01-01

181

Anatomy of the rat knee joint and fibre composition of a major articular nerve.  

PubMed

Several recent reports discuss the role of joint nerves in arthritis. Many of these are based on studies in the rat. The aim of this study is to examine the anatomy of the rat knee joint, in search for a primary articular nerve, and to analyze the fibre composition of that nerve. The results show that the structure of the joint differs in some respects from the human knee. At the upper end of the bony patella a cartilaginous patella extends proximally, forming the anterior wall of the suprapatellar bursa. Distinct collateral ligaments are integrated in the joint capsule. The extensor digitorum longus muscle bridges the knee joint, originating from the lateral femoral epicondyle. The well-developed menisci contain pyramid-shaped ossicles. The cruciate ligaments are arranged like in the human knee. A large posterior (PAN) and a small medial (MAN) articular nerve can be identified. The PAN is composed of some 400 axons, about 80% of which are unmyelinated. All myelinated fibres are sensory. They present a unimodal size spectrum with a size range of 1-8 microns, and a predominance of small fibres. Specific denervations indicate that about 1/3 of the unmyelinated axons represent afferents, and some 2/3 are sympathetic efferents. Interestingly, neonatal capsaicin treatment did not influence the number of unmyelinated PAN axons. The functional significance of the numerous unmyelinated sympathetic and sensory PAN axons in the normal knee joint remains to be elucidated. PMID:2048758

Hildebrand, C; Oqvist, G; Brax, L; Tuisku, F

1991-04-01

182

Arthritis in a glyptodont (Mammalia, Xenarthra, Cingulata).  

PubMed

Arthritic lesions have been frequently diagnosed in the fossil record, with spondyloarthropathy (a type of erosive and pan-mammalian arthritis) being one of the most common types described to date for mammals, though not restricted to this group. Here, we identify spondyloarthropathy in fossil bones from the late Pleistocene in Brazil assignable to a large glyptodont individual. Bone erosions in the peripheral joints (viz., the ulna, radius, left femur and tibiae-fibulae) associated with osteosclerosis allow the diagnosis of spondyloarthropathy. The presence of osteophytes in seven bones of the forelimbs (viz., the ulna and radius) and hind limbs (viz., the tibiae-fibulae, left femur and patellae) and a subchondral cyst in one element (viz., the left femur) indicate secondary osteoarthritis. A calcified deposition on the articular surface of the left patella indicates the presence of calcium pyrophosphate deposition disease, which, like the observed osteoarthritic alterations, likely represents a complication of spondyloarthropathy. This is the first report of spondyloarthropathy for xenarthrans. PMID:24551126

Barbosa, Fernando Henrique de Souza; Porpino, Kleberson de Oliveira; Fragoso, Ana Bernadete Lima; Oliveira, Edison Vicente

2014-01-01

183

Spontaneous bilateral avulsion fracture of the tuberositas tibiae in a New Zealand White rabbit - A counterpart to Osgood-Schlatter disease in humans?  

PubMed

The first reported case describing a spontaneous bilateral avulsion fracture of the tuberositas tibiae in a New Zealand White rabbit is presented. So far in animals, this condition has been only described in dogs and horses. In humans, this condition is also called Osgood-Schlatter disease (OSD) or syndrome, traction apophysitis of the tibial tubercle (ATT) or patellar tendon enthesopathy of the tibial tuberosity respectively. It is mainly seen in young adolescents coinciding with periods of growth spurts. In humans, its pathogenesis is believed to be caused by repetitive tendon/muscle strain at the insertion of the patellar tendon to the immature tibial tuberosity, which has its own secondary ossification center. Morphologically this case is characterized by bilateral chronic avulsion with incomplete separation of the tuberositas tibae, and proximal dislocation of the patella (patella alta). Despite these marked pathological changes, the animal was clinically without findings. Nevertheless, this case emphasizes the need for thorough clinical and radiological examination of rabbits intended for preclinical research studies prior to study begin, especially in orthopedic research. PMID:25435475

Nehrbass, D; Arens, D; Zeiter, S

2015-02-01

184

The role of osteonecrosis in canine coronoid dysplasia: arthroscopic and histopathological findings.  

PubMed

Coronoid dysplasia (CD) or medial coronoid disease is part of canine elbow dysplasia and eventually results in osteoarthrosis. Although CD was originally attributed to disturbed endochondral ossification, more recent data point to the subchondral bone. The objective of this study was to assess dysplastic bone and cartilage of dogs that underwent unilateral or bilateral arthroscopic subtotal coronoidectomy for the treatment of CD. Arthroscopic findings and histopathology of bone and cartilage removed from elbow joints with CD were compared. The most common arthroscopic finding was fragmentation with softening of the subchondral bone of the central part of the medial coronoid process. In dogs without obvious fragmentation, CD was characterised by bone softening and chondromalacia. During arthroscopic intervention dysplastic bone and cartilage were collected for histopathological assessment. Forty-five slices of formalin-fixed, paraffin-embedded bone and cartilage samples were stained using haematoxylin and eosin and evaluated. Histopathological findings primarily consisted of osteonecrosis of subchondral bone with necrosis within the marrow spaces. Histopathological changes in the articular cartilage were characterised by fibrillation, chondrocyte clone formation, and focal cartilage necrosis. The pathology was found primarily in the subchondral bone and not in the articular cartilage. Vascular compromise may play a role in the pathogenesis of osteonecrosis in CD. PMID:24797106

Mariee, I C; Gröne, A; Theyse, L F H

2014-06-01

185

Mathematical simulations of photon interactions using Monte Carlo analysis to evaluate the uncertainty associated with in vivo K X-ray fluorescence measurements of stable lead in bone  

NASA Astrophysics Data System (ADS)

This research utilized Monte Carlo N-Particle version 4C (MCNP4C) to simulate K X-ray fluorescent (K XRF) measurements of stable lead in bone. Simulations were performed to investigate the effects that overlying tissue thickness, bone-calcium content, and shape of the calibration standard have on detector response in XRF measurements at the human tibia. Additional simulations of a knee phantom considered uncertainty associated with rotation about the patella during XRF measurements. Simulations tallied the distribution of energy deposited in a high-purity germanium detector originating from collimated 88 keV 109Cd photons in backscatter geometry. Benchmark measurements were performed on simple and anthropometric XRF calibration phantoms of the human leg and knee developed at the University of Cincinnati with materials proven to exhibit radiological characteristics equivalent to human tissue and bone. Initial benchmark comparisons revealed that MCNP4C limits coherent scatter of photons to six inverse angstroms of momentum transfer and a Modified MCNP4C was developed to circumvent the limitation. Subsequent benchmark measurements demonstrated that Modified MCNP4C adequately models photon interactions associated with in vivo K XRF of lead in bone. Further simulations of a simple leg geometry possessing tissue thicknesses from 0 to 10 mm revealed increasing overlying tissue thickness from 5 to 10 mm reduced predicted lead concentrations an average 1.15% per 1 mm increase in tissue thickness (p < 0.0001). An anthropometric leg phantom was mathematically defined in MCNP to more accurately reflect the human form. A simulated one percent increase in calcium content (by mass) of the anthropometric leg phantom's cortical bone demonstrated to significantly reduce the K XRF normalized ratio by 4.5% (p < 0.0001). Comparison of the simple and anthropometric calibration phantoms also suggested that cylindrical calibration standards can underestimate lead content of a human leg up to 4%. The patellar bone structure in which the fluorescent photons originate was found to vary dramatically with measurement angle. The relative contribution of lead signal from the patella declined from 65% to 27% when rotated 30°. However, rotation of the source-detector about the patella from 0 to 45° demonstrated no significant effect on the net K XRF response at the knee.

Lodwick, Camille J.

186

Mechanical effects of surgical procedures on osteochondral grafts elucidated by osmotic loading and real-time ultrasound  

PubMed Central

Introduction Osteochondral grafts have become popular for treating small, isolated and full-thickness cartilage lesions. It is recommended that a slightly oversized, rather than an exact-sized, osteochondral plug is transplanted to achieve a tight fit. Consequently, impacting forces are required to insert the osteochondral plug into the recipient site. However, it remains controversial whether these impacting forces affect the biomechanical condition of the grafted articular cartilage. The present study aimed to investigate the mechanical effects of osteochondral plug implantation using osmotic loading and real-time ultrasound. Methods A full-thickness cylindrical osteochondral defect (diameter, 3.5 mm; depth, 5 mm) was created in the lateral lower quarter of the patella. Using graft-harvesting instruments, an osteochondral plug (diameter, 3.5 mm as exact-size or 4.5 mm as oversize; depth, 5 mm) was harvested from the lateral upper quarter of the patella and transplanted into the defect. Intact patella was used as a control. The samples were monitored by real-time ultrasound during sequential changes of the bathing solution from 0.15 M to 2 M saline (shrinkage phase) and back to 0.15 M saline (swelling phase). For cartilage sample assessment, three indices were selected, namely the change in amplitude from the cartilage surface (amplitude recovery rate: ARR) and the maximum echo shifts from the cartilage surface and the cartilage-bone interface. Results The ARR is closely related to the cartilage surface integrity, while the echo shifts from the cartilage surface and the cartilage-bone interface are closely related to tissue deformation and NaCl diffusion, respectively. The ARR values of the oversized plugs were significantly lower than those of the control and exact-sized plugs. Regarding the maximum echo shifts from the cartilage surface and the cartilage-bone interface, no significant differences were observed among the three groups. Conclusions These findings demonstrated that osmotic loading and real-time ultrasound were able to assess the mechanical condition of cartilage plugs after osteochondral grafting. In particular, the ARR was able to detect damage to the superficial collagen network in a non-destructive manner. Therefore, osmotic loading and real-time ultrasound are promising as minimally invasive methods for evaluating cartilage damage in the superficial zone after trauma or impact loading for osteochondral grafting. PMID:19725961

2009-01-01

187

The Role of Trochleoplasty in Patellofemoral Instability  

PubMed Central

The management of recurrent patellofemoral instability is challenging. The etiology of the instability is multifactorial, requiring the examination of lower limb alignment, relationship of the patella to the trochlear groove and tibial tubercle, and the soft-tissue restraints. As initial surgical efforts were aimed at isolated soft-tissue repair or reconstruction, patients often had continued instability. Thus, a heightened interest in trochleoplasty has occurred as trochlear dysplasia has been found in 85% of patients with recurrent instability. Different types of trochleoplasties have been developed depending on the type of dysplasia including the trochlear lengthening osteotomy, the proximal open trochleoplasty, the deepening trochleoplasty, and the arthroscopic deepening trochleoplasty. The techniques, benefits, and results of these trochleoplasties will be presented in this review. PMID:22878658

Duncan, Stephen T.; Noehren, Brian S.; Lattermann, Christian

2014-01-01

188

Bone Ingrowth in Well-Fixed Retrieved Porous Tantalum Implants  

PubMed Central

While first generation porous coatings have had clinical success, aseptic loosening remains a leading cause of revision. The purpose of this study was to investigate the reason for revision and to assess the amount of bone ingrowth in retrieved porous tantalum components. In a prospective multicenter retrieval program, 76 porous tantalum acetabular shells, 5 femoral stems, 7 patellas and 36 tibial trays were collected from revision surgeries. A subset of the implants were analyzed for bone ingrowth. The main reason for revision was infection for acetabular shells (1.4 year implantation time) and instability for tibial trays (1.8 years implantation time). Two of the thirty primary surgery acetabular shells and one of the thirty-six primary surgery tibial trays were revised for implant loosening. We observed full depth penetration of bone into the porous tantalum layer for the acetabular shells and femoral stems. PMID:23518432

Hanzlik, Josa A.; Day, Judd S.

2013-01-01

189

Bone ingrowth in well-fixed retrieved porous tantalum implants.  

PubMed

While first generation porous coatings have had clinical success, aseptic loosening remains a leading cause of revision. The purpose of this study was to investigate the reasons for revision and to assess the amount of bone ingrowth in retrieved porous tantalum components. In a prospective multicenter retrieval program, 76 porous tantalum acetabular shells, 5 femoral stems, 7 patellas and 36 tibial trays were collected from revision surgeries. A subset of the implants was analyzed for bone ingrowth. The main reason for revision was infection for acetabular shells (1.4 years implantation time) and instability for tibial trays (1.8 years implantation time). Two of the thirty primary surgery acetabular shells and one of the thirty-six primary surgery tibial trays were revised for implant loosening. We observed full depth penetration of bone into the porous tantalum layer for the acetabular shells and femoral stems. PMID:23518432

Hanzlik, Josa A; Day, Judd S

2013-06-01

190

Neglected locked vertical patellar dislocation.  

PubMed

Patellar dislocations occurring about the vertical and horizontal axis are rare and irreducible. The neglected patellar dislocation is still rarer. We describe the clinical presentation and management of a case of neglected vertical patellar dislocation in a 6 year-old boy who sustained an external rotational strain with a laterally directed force to his knee. Initially the diagnosis was missed and 2 months later open reduction was done. The increased tension generated by the rotation of the lateral extensor retinaculum kept the patella locked in the lateral gutter even with the knee in full extension. Traumatic patellar dislocation with rotation around a vertical axis has been described earlier, but no such neglected case has been reported to the best of our knowledge. PMID:23162154

Gupta, Rakesh Kumar; Gupta, Vinay; Sangwan, Sukhbir Singh; Kamboj, Pradeep

2012-09-01

191

Imaging pediatric sports injuries: lower extremity.  

PubMed

Injuries to pediatric athletes, which are becoming increasingly common, take the form of acute injuries and chronic overuse injuries. Acute injuries of the lower extremity include avulsions of the pelvic apophyses, muscle-tendon injuries, transient dislocation of the patella, ankle sprains, and acute tears of the anterior cruciate ligament and menisci. Magnetic resonance (MR) imaging of the latter 2 injuries should approach the accuracy of MR imaging of the adult knee. Chronic overuse injuries of the lower extremity in this age group include stress fractures, which are most common in the tibia; ankle impingement syndromes; osteochondritis dissecans of the knee and osteochondral lesions of the talus; and traction apophysitis, most commonly presenting as Osgood-Schlatter disease and Sinding-Larsen-Johannson disease, affecting the patellar tendon. Imaging findings of all these lesions are characteristic, and allow radiologists to assist their clinical colleagues in diagnosing and treating pediatric athletic injuries. PMID:21094407

Davis, Kirkland W

2010-11-01

192

Histopathological study of nonosseous tarsal coalition.  

PubMed

Histopathological analysis was performed on 55 feet in 48 patients with nonosseous tarsal coalitions. Histological findings were similar to those observed at the tendinous attachment site of Osgood-Schlatter disease, accessory navicular, and bipartite patellae. No nerve elements were observed in the fibrocartilaginous tissue at the coalition. Nerve elements were present only in periosteum and articular capsule surrounding the coalition. Pain in the tarsal coalition is not mediated by nerve elements at the coalition site itself. It is assumed that the pain is caused by mechanical abnormality that results from incomplete coalition. Incomplete coalition produces microfractures and remodelings on the boundaries between bone and the coalition, which then lead to degenerative changes. This mechanical abnormality seems to induce pain via free nerve endings in the periosteum and in the articular capsule surrounding the coalition. PMID:9728699

Kumai, T; Takakura, Y; Akiyama, K; Higashiyama, I; Tamai, S

1998-08-01

193

Apophyseal injuries in the young athlete.  

PubMed

Apophyseal injuries, which are unique in the adolescent athlete, cause inflammation at the site of a major tendinous insertion onto a growing bony prominence. These injuries typically occur in active adolescents between the ages of eight and 15 years and usually present as periarticular pain associated with growth, skeletal immaturity, repetitive microtrauma and muscle-tendon imbalance. Common apophyseal injuries, and their sites, include Sever's disease (posterior calcaneus), Osgood-Schlatter disease (tibial tuberosity), Sindig-Larsen-Johansson syndrome (inferior patella), medial epicondylitis (humeral medial epicondyle) and apophysitis of the hip (iliac crest, ischial tuberosity). Conservative therapy, including rest, ice, compression, elevation, nonsteroidal anti-inflammatory agents, modification of the athlete's activity level and exercises for increased flexibility and strengthening, is usually effective. PMID:7762480

Peck, D M

1995-06-01

194

[Osgood-Schlatter disease].  

PubMed

Osgood-Schlatter disease is a painful affection of the knee which touches particularly the active teenagers. Etiology of this frequent affection is unknown. This disease appears as an anterior knee pain and swelling started and worsened by the sports activities. Diagnosis is especially clinical. X-Rays, ultrasounds or IRM are not necessary for the diagnosis. Treatment is based on eviction of sports, analgesics and sometimes physiotherapy. Surgery is rarely proposed. Knee pain stops at the end of the growth. Long-term outcome is good for the majority of the patients. Some studies suggest a patella alta at the end of the growth, without an established correlation with knee arthritis. PMID:18946967

Vargas, Bernardo; Lutz, Nicolas; Dutoit, Michel; Zambelli, Pierre Yves

2008-09-24

195

Effects of Kinesiology Taping on Repositioning Error of the Knee Joint after Quadriceps Muscle Fatigue  

PubMed Central

[Purpose] The purpose of this study was to identify the effects of kinesiology taping on repositioning error of the knee joint after quadriceps muscle fatigue. [Subjects] Thirty healthy adults with no orthopaedic or neurological problems participated in this study. [Methods] The repositioning error of the knee joint was measured using a digital goniometer when the subjects extended their dominant-side knee to a random target angle (30°, 45°, or 60°) with their eyes closed, before and after a quadriceps muscle fatigue protocol, and after application of kinesiology tape. [Results] We found that repositioning errors of the dominant-side knee joint increased after quadriceps fatigue compared with no-fatigue conditions. However, kinesiology taping of the quadriceps muscle and patella after quadriceps fatigue significantly decreased repositioning errors of the knee joint. [Conclusion] These results suggest that quadriceps fatigue increases the repositioning error of the knee joint, whereas application of kinesiology tape decreases fatigue-induced joint repositioning error. PMID:25013297

Han, Jin Tae; Lee, Jung-hoon

2014-01-01

196

Illness perceptions and activity limitations in osteoarthritis of the knee: a case report intervention study.  

PubMed

This case report describes the process and outcome of an intervention where illness perceptions (IPs) were targeted in order to reduce limitations in daily activities. The patient was a 45-year-old woman diagnosed with posttraumatic secondary osteoarthritis of the lateral patella-femoral cartilage of the right knee. At baseline, the patient reported maladaptive IPs on the Brief Illness Perception Questionnaire Dutch Language Version and limitations in walking stairs, cycling and walking. Fewer limitations in daily activities are hypothesized by changing maladaptive IPs into more favourable IPs. In this case report, discussing maladaptive IPs with the patient was the main intervention. A participatory decision making model was used as a design by which the maladaptive IP were discussed. Six out of eight maladaptive IPs changed favourably and there was a clinically relevant decrease in limitations of daily activities. The Global Perceived Effect was rated as much improved. PMID:24011782

de Raaij, Edwin J; Pool, Jan; Maissan, François; Wittink, Harriët

2014-04-01

197

Patellar Tendinopathy - Recent Developments toward Treatment.  

PubMed

Patellar tendinopathy (PT) is a clinical and chronic overuse condition of unknown pathogenesis and etiology marked by anterior knee pain typically manifested at the inferior pole of the patella. PT has been referred to as "jumper's knee" since it is particularly common among populations of jumping athletes, such as basketball and volleyball play- ers. Due to its common refractory response to conservative treatment, a variety of new treatments have emerged recently that include dry-needling, sclerosing injections, platelet-rich plasma therapy, arthroscopic surgical procedures, surgical resection of the inferior patellar pole, extracorporeal shock wave treatment, and hyperthermia thermotherapy. Since PT has an unknown pathogenesis and etiology, PT treatment is more a result of physician experience than evidence-based science. This review will summarize the current literature on this topic, identify current research efforts aimed to understand the pathological changes in abnormal tendons, provide exposure to the emerging treatment techniques, and provide suggested direction for future research. PMID:25429390

Christian, Robert A; Rossy, William H; Sherman, Orrin H

2014-01-01

198

Total knee arthroplasty in patients with a previous patellectomy.  

PubMed

Post-patellectomy patients represent a specific subgroup of patients that may develop arthritis and persistent knee pain and potentially require treatment with total knee arthroplasty. This article reviews the treatment and functional outcomes following total knee arthroplasty in patients with prior patellectomy. A case report is presented as an example of the clinical management of a post-patellectomy patient with significant knee pain and disability treated with total knee arthroplasty. Emphasis will be placed in decision- making, specifically with the use of a posterior stabilized implant. In addition, postoperative strengthening of the quadriceps is essential to compensate for the lack of the patella and increase the success of total knee arthroplasty in this subgroup of patients. PMID:24151951

Maslow, Jed; Zuckerman, Joseph D; Immerman, Igor

2013-01-01

199

Anterior cruciate ligament reconstruction best practice: A review of graft choice  

PubMed Central

There is much literature about differing grafts used in anterior cruciate ligament (ACL) reconstruction. Much of this is of poor quality and of a low evidence base. We review and summarise the literature looking at the four main classes of grafts used in ACL reconstruction; bone-patella tendon-bone, hamstrings, allograft and synthetic grafts. Each graft has the evidence for its use reviewed and then compared, where possible, to the others. We conclude that although there is no clear “best” graft, there are clear differences between the differing graft choices. Surgeon’s need to be aware of the evidence behind these differences, in order to have appropriate discussions with their patients, so as to come to an informed choice of graft type to best suit each individual patient and their requirements. PMID:24649411

Shaerf, Daniel A; Pastides, Philip S; Sarraf, Khaled M; Willis-Owen, Charles A

2014-01-01

200

[Nails semiology].  

PubMed

For those interested in nails, a fairly good knowledge of the anatomy of the nail unit is indispensable. But nothing will replace a careful, clinical examination of the nail apparatus. The shape of the nail, surface abnormalities and coloration, with or without a magnifying glass, may well provide a medical diagnosis not only in dermatology but also for medicine in general. Pits on the surface of the nail plate may be enough to diagnose psoriasis on a limited area of scalp dandruff. Even partial detachment of the nail apparatus might lead to the suspicion of psoriatic arthritis. A triangular lunula is associated with the absence of patellas. Finally, no pulmonary examination of a smoker is complete without looking for clubbing. It is high time to pay tribute to the nail. PMID:25443634

Baran, Robert

2014-11-01

201

Bilateral patellar component shear failure of highly cross-linked polyethylene components: report of a case and laboratory analysis of failure mechanisms.  

PubMed

A case of bilateral patellar component failure due to fatigue fracture of the all-polyethylene fixation pegs in a highly cross-linked ultra-high-molecular-weight polyethylene design is presented. To recreate this failure mode, a novel test method was developed to investigate the effects of peg orientation and cement technique on patella fatigue strength under cyclic compression and shear loading. Patellar peg orientation had a minor effect on shear strength, whereas lack of cement in the backside patellar groove had a substantial effect. The shear fatigue strength exceeded in vivo force estimates when the patellar groove was fully cemented. The test results and retrieval analysis suggest that high activity level and inadequate cement fixation of the patellar component may contribute to all-polyethylene patellar component peg fractures. PMID:21978565

Stulberg, Bernard N; Wright, Timothy M; Stoller, Alex P; Mimnaugh, Kimberly L; Mason, James J

2012-05-01

202

Effects of kinesiology taping on repositioning error of the knee joint after quadriceps muscle fatigue.  

PubMed

[Purpose] The purpose of this study was to identify the effects of kinesiology taping on repositioning error of the knee joint after quadriceps muscle fatigue. [Subjects] Thirty healthy adults with no orthopaedic or neurological problems participated in this study. [Methods] The repositioning error of the knee joint was measured using a digital goniometer when the subjects extended their dominant-side knee to a random target angle (30°, 45°, or 60°) with their eyes closed, before and after a quadriceps muscle fatigue protocol, and after application of kinesiology tape. [Results] We found that repositioning errors of the dominant-side knee joint increased after quadriceps fatigue compared with no-fatigue conditions. However, kinesiology taping of the quadriceps muscle and patella after quadriceps fatigue significantly decreased repositioning errors of the knee joint. [Conclusion] These results suggest that quadriceps fatigue increases the repositioning error of the knee joint, whereas application of kinesiology tape decreases fatigue-induced joint repositioning error. PMID:25013297

Han, Jin Tae; Lee, Jung-Hoon

2014-06-01

203

Anterior cruciate ligament reconstruction best practice: A review of graft choice.  

PubMed

There is much literature about differing grafts used in anterior cruciate ligament (ACL) reconstruction. Much of this is of poor quality and of a low evidence base. We review and summarise the literature looking at the four main classes of grafts used in ACL reconstruction; bone-patella tendon-bone, hamstrings, allograft and synthetic grafts. Each graft has the evidence for its use reviewed and then compared, where possible, to the others. We conclude that although there is no clear "best" graft, there are clear differences between the differing graft choices. Surgeon's need to be aware of the evidence behind these differences, in order to have appropriate discussions with their patients, so as to come to an informed choice of graft type to best suit each individual patient and their requirements. PMID:24649411

Shaerf, Daniel A; Pastides, Philip S; Sarraf, Khaled M; Willis-Owen, Charles A

2014-01-18

204

Total knee arthroplasty in patients with ipsilateral fused hip: a technical note.  

PubMed

We report the surgical technique used to perform posterior-stabilized total knee arthroplasty (TKA) in two patients with a well positioned and functional hip arthrodesis. Intraoperatively, the operating table was placed in an increased Trendelenburg position. Episodically, we flexed the foot of the table by 90° to allow maximal knee flexion to facilitate exposure and bone cuts. We opted to resect the patella and tibia first to enable exposure, given the stiffness of the arthritic knee. One patient's medical condition prohibited complex conversion total hip arthroplasty (THA) prior to the TKA. The other patient's scarred soft tissues around the hip, due to chronic infection and multiple operations, made THA risky. The final outcome provided satisfactory results at a minimum of 2 years postoperatively. TKA can be successfully performed with adjustments of table position and modification of the sequence of surgical steps in patients with ipsilateral hip fusion. PMID:25436074

Goodman, Stuart B; Huddleston, James I; Hur, Dong; Song, Sang Jun

2014-12-01

205

The use of rapid prototyped implants to simulate knee joint abnormalities for in vitro testing: a validation study with replica implants of the native trochlea.  

PubMed

To investigate the biomechanical effect of skeletal knee joint abnormalities, the authors propose to implant pathologically shaped rapid prototyped implants in cadaver knee specimens. This new method was validated by replacing the native trochlea by a replica implant on four cadaver knees with the aid of cadaver-specific guiding instruments. The accuracy of the guiding instruments was assessed by measuring the rotational errors of the cutting planes (on average 3.01° in extension and 1.18° in external/internal rotation). During a squat and open chain simulation, the patella showed small differences in its articulation with the native trochlea and the replica trochlea, which could partially be explained by the rotational errors of the implants. This study concludes that this method is valid to investigate the effect of knee joint abnormalities with a replica implant as a control condition to account for the influence of material properties and rotational errors of the implant. PMID:25205750

Van Haver, Annemieke; De Roo, Karel; De Beule, Matthieu; Van Cauter, Sofie; Labey, Luc; De Baets, Patrick; Claessens, Tom; Verdonk, Peter

2014-08-01

206

Dynamic simulation of tibial tuberosity realignment: model evaluation.  

PubMed

This study was performed to evaluate a dynamic multibody model developed to characterize the influence of tibial tuberosity realignment procedures on patellofemoral motion and loading. Computational models were created to represent four knees previously tested at 40°, 60°, and 80° of flexion with the tibial tuberosity in a lateral, medial and anteromedial positions. The experimentally loaded muscles, major ligaments of the knee, and patellar tendon were represented. A repeated measures ANOVA with post-hoc testing was performed at each flexion angle to compare data between the three positions of the tibial tuberosity. Significant experimental trends for decreased patella flexion due to tuberosity anteriorization and a decrease in the lateral contact force due to tuberosity medialization were reproduced computationally. The dynamic multibody modeling technique will allow simulation of function for symptomatic knees to identify optimal surgical treatment methods based on parameters related to knee pathology and pre-operative kinematics. PMID:25025488

Purevsuren, Tserenchimed; Elias, John J; Kim, Kyungsoo; Kim, Yoon Hyuk

2015-11-01

207

Total Knee Arthroplasty in Patients with Ipsilateral Fused Hip: A Technical Note  

PubMed Central

We report the surgical technique used to perform posterior-stabilized total knee arthroplasty (TKA) in two patients with a well positioned and functional hip arthrodesis. Intraoperatively, the operating table was placed in an increased Trendelenburg position. Episodically, we flexed the foot of the table by 90° to allow maximal knee flexion to facilitate exposure and bone cuts. We opted to resect the patella and tibia first to enable exposure, given the stiffness of the arthritic knee. One patient's medical condition prohibited complex conversion total hip arthroplasty (THA) prior to the TKA. The other patient's scarred soft tissues around the hip, due to chronic infection and multiple operations, made THA risky. The final outcome provided satisfactory results at a minimum of 2 years postoperatively. TKA can be successfully performed with adjustments of table position and modification of the sequence of surgical steps in patients with ipsilateral hip fusion. PMID:25436074

Goodman, Stuart B.; Huddleston, James I.; Hur, Dong

2014-01-01

208

[Soft tissue balancing in valgus gonarthrosis].  

PubMed

Implanting a condylar knee in patients with valgus deformity is challenging both for the surgeon and in terms of clinical instrumentation. Valgus deformity - defined as an anatomic angle >10 degrees - consists of a bony and a soft tissue component. Frequently, the lateral femoral condyle is hypoplastic and can create a secondary osteochondral lesion on the tibial plateau. Concomitantly, there is a soft tissue contracture of the lateral side with an elongation of the medial collateral ligament. Correction of the deformity and restoration of anatomic alignment should be achieved to maximize the longevity of the replaced components. Soft tissue balancing is crucial for successful treatment. This is achieved if a symmetrical flexion and extension gap together with a centralized patella position is obtained. We describe our surgical approach to address valgus deformities in primary total knee arthroplasty with special emphasize on a stepwise release of tight lateral capsular and ligamentous structures controlled by a knee balancer. PMID:17563870

Pape, D; Kohn, D

2007-07-01

209

Arthroscopic Technique for the Treatment of Patellar Chondral Lesions With the Patient in the Supine Position  

PubMed Central

We describe an arthroscopic approach for the treatment of patellar chondral lesions with the patient in the supine position. This approach can be used to perform certain procedures such as matrix autologous chondrocyte implantation and autologous matrix–induced chondrogenesis. It is possible to perform these arthroscopic techniques working at an angle perpendicular to the patellar joint surface. First, with the patient in the supine position, arthroscopic longitudinal sectioning of the lateral patellar retinaculum is performed, and the patella is reverted with the help of a Codivilla forceps. It is then possible to place the chondral surface perpendicular to the floor, and it can be accessed directly through a lateral parapatellar portal. Short-term follow-up has shown the benignity of opening the patellar retinaculum. This procedure reduces morbidity compared with the traditional open surgery. PMID:25126506

Cuéllar, Ricardo; Cuéllar, Adrián; Ponte, Juan; Ruiz-Ibán, Miguel A.

2014-01-01

210

Extended proximal trochleoplasty for the correction of bidirectional patellar luxation in seven Pomeranian dogs.  

PubMed

Seven Pomeranians with bidirectional patellar luxation (BPL) were prospectively studied regarding aetiology and results of a new surgical technique. Radiographic evaluation of the ratio between patellar ligament length and patellar bone length revealed no differences between Pomeranians with bidirectional patellar luxation and healthy stifle joints. Functional rather than anatomic patella alta might be associated with bidirectional patellar luxation in Pomeranians. The surgical outcome of extended proximal trochleoplasty was good-to-excellent in 87·5% of the stifles and all dogs achieved functional recovery. There was only minimal radiographic progression of osteophyte formation at 48 weeks after surgery. To the authors' knowledge, this is the first report on bidirectional patellar luxation in small breed dogs and its successful surgical treatment. PMID:25040469

Wangdee, C; Hazewinkel, H A W; Temwichitr, J; Theyse, L F H

2015-02-01

211

Abnormal Tibiofemoral Kinematics Following ACL Reconstruction are Associated with Early Cartilage Matrix Degeneration Measured by MRI T1rho  

PubMed Central

Purpose Altered kinematics following ACL-reconstruction may be a cause of post-traumatic osteoarthritis. T1? MRI is a technique that detects early cartilage matrix degeneration. Our study aimed to evaluate kinematics following ACL-reconstruction, cartilage health (using T1? MRI), and assess whether altered kinematics following ACL-reconstruction are associated with early cartilage degeneration. Methods Eleven patients (average age: 33±9 years) underwent 3T MRI 18±5 months following ACL-reconstruction. Images were obtained at extension and 30° flexion under simulated loading (125 N). Tibial rotation (TR) and anterior tibial translation (ATT) between flexion and extension, and T1? relaxation times of the knee cartilage were analyzed. Cartilage was divided into five compartments: medial and lateral femoral condyles (MFC/LFC), medial and lateral tibias (MT/LT), and patella. A sub-analysis of the femoral weight-bearing (wb) regions was also performed. Patients were categorized as having “abnormal” or “restored” ATT and TR, and T1? percentage increase was compared between these two groups of patients. Results As a group, there were no significant differences between ACL-reconstructed and contralateral knee kinematics, however, there were individual variations. T1? relaxation times of the MFC and MFC-wb region were elevated (p?0.05) in the ACL-reconstructed knees compared to the uninjured contralateral knees. There were increases (p?0.05) in the MFC-wb, MT, patella and overall average cartilage T1? values of the “abnormal” ATT group compared to “restored” ATT group. The percentage increase in the T1? relaxation time in the MFC-wb cartilage approached significance (p=0.08) in the “abnormal” versus “restored” TR patients. Conclusions Abnormal kinematics following ACL-reconstruction appears to lead to cartilage degeneration, particularly in the medial compartment. PMID:21807522

Haughom, Bryan; Schairer, William; Souza, Richard B.; Carpenter, Dana; Ma, C Benjamin; Li, Xiaojuan

2011-01-01

212

Infrapatellar Straps Decrease Patellar Tendon Strain at the Site of the Jumper’s Knee Lesion  

PubMed Central

Background: The impetus for the use of patellar straps in the treatment of patellar tendinopathy has largely been based on empirical evidence and not on any mechanistic rationale. A computational model suggests that patellar tendinopathy may be a result of high localized tendon strains that occur at smaller patella–patellar tendon angles (PPTAs). Hypothesis: Infrapatellar straps will decrease the mean localized computational strain in the area of the patellar tendon commonly involved in jumper’s knee by increasing the PPTA. Study Design: Controlled laboratory study. Methods: Twenty adult males had lateral weightbearing and nonweightbearing radiographs of their knees taken with and without 1 of 2 infrapatellar straps at 60° of knee flexion. Morphologic measurements of PPTA and patellar tendon length with and without the straps were used as input data into a previously described computational model to calculate average and maximum strain at the common location of the jumper’s knee lesion during a simulated jump landing. Results: The infrapatellar bands decreased the predicted localized strain (average and maximum) in the majority of participants by increasing PPTA and/or decreasing patellar tendon length. When both PPTA and patellar tendon length were altered by the straps, there was a strong and significant correlation with the change in predicted average localized strain with both straps. Conclusion: Infrapatellar straps may limit excessive patella tendon strain at the site of the jumper’s knee lesion by increasing PPTA and decreasing patellar tendon length rather than by correcting some inherent anatomic or functional abnormality in the extensor apparatus. Clinical Relevance: The use of infrapatellar straps may help prevent excessive localized tendon strains at the site of the jumper’s knee lesion during a jump landing. PMID:23016021

Lavagnino, Michael; Arnoczky, Steven P.; Dodds, Julie; Elvin, Niell

2011-01-01

213

Stress avulsion of the tibial tuberosity after tension band wiring of a patellar fracture: a case report  

PubMed Central

Introduction To the best of our knowledge there is no other report of an elderly patient who was surgically treated for a patellar fracture with tension band wiring and who subsequently suffered from an avulsion fracture of the tibial tuberosity. The combination of a patellar fracture and avulsion of the patellar ligament has only been described as complication after bone-patellar tendon-bone anterior cruciate ligament reconstructions. However, due to demographic changes and more elderly patients treated this injury may become more frequent in future. Case presentation We present the case of an 81 year old female who sustained an oblique patellar fracture after a direct contact injury of the left knee when falling on ice. Consequently the patellar fracture was openly reduced and stabilized with tension band wiring. The follow-up was uneventful till three months after surgery when the patient noticed a spontaneous avulsion fracture of the tibial tuberosity (Ogden type 3). The tibial tuberosity fragment was reattached with two non-resorbable sutures looped around two modified AO cortical 3.5 mm long neck screws. Intraoperatively multiple bone cysts were seen. Biopsies were not taken to prevent further fragmentation of the tibial tuberosity. The patient was followed up with anteroposterior and lateral full weight bearing radiographs and clinical assessment at 6, 12 weeks and 6 months after surgery. Recovery was completely pain free with full satisfaction. Conclusion In conclusion in elderly patients with a patella fracture a possible associated but not obvious fracture of the tibial tuberosity should be ruled out and the postoperative rehabilitation protocol after tension band wiring of the patella might have to be individually adjusted to bone quality and course of the fracture. PMID:20062606

2009-01-01

214

Anterior opening wedge osteotomy of the proximal tibia for anterior knee pain in idiopathic hyperextension knees  

PubMed Central

We analysed 20 patients with 24 knees affected by idiopathic genu recurvatum who were treated with an anterior opening wedge osteotomy of the proximal tibia because of anterior knee pain. We managed to attain full satisfaction in 83% of the patients with a mean follow-up of 7.4 years. The mean Hospital for Special Surgery score was 90.3 (range 70.5–99.5), and the mean Knee Society score score was 94.6 (70–100) for function and 87.7 (47–100) for pain. The mean Western Ontario and McMaster University Osteoarthritis Index score for knee function was 87.5 (42–100), for stiffness 82.8 (25–100) and for pain 87.3 (55–100). Radiographs showed a significant increase in posterior tibial slope of 9.4 deg and a significant decrease of patellar height according to the Blackburne–Peel method of 0.16 postoperatively. No cases of non-union, deep infection or compartment syndrome were seen. No osteoarthritic changes in the lateral or medial knee compartment were found with more than 5 years’ follow-up in 16 patients with 19 affected knees. Three out of the four dissatisfied patients had a patella infera which led to patellofemoral complaints. One patient in the study underwent a secondary superior displacement of the patella with excellent results. We conclude that in a selected group of patients with idiopathic genu recurvatum and anterior knee pain an opening wedge osteotomy of the proximal tibia can be beneficial. PMID:16521014

van Raaij, T. M.

2006-01-01

215

Load-Dependent Variations in Knee Kinematics Measured with Dynamic MRI  

PubMed Central

Subtle changes in knee kinematics may substantially alter cartilage contact patterns and moment generating capacities of soft tissues. The objective of this study was to use dynamic magnetic resonance imaging (MRI) to measure the influence of the timing of quadriceps loading on in vivo tibiofemoral and patellofemoral kinematics. We tested the hypothesis that load-dependent changes in knee kinematics would alter both the finite helical axis of the tibiofemoral joint and the moment arm of the patellar tendon. Eight healthy young adults were positioned supine in a MRI-compatible device that could impose either elastic or inertial loads on the lower leg in response to cyclic knee flexion-extension. The elastic loading condition induced concentric quadriceps contractions with knee extension, while an inertial loading condition induced eccentric quadriceps contractions with knee flexion. Peak internal knee extension moments ranged from 23–33 Nm, which is comparable to loadings seen in normal walking. We found that anterior tibia translation, superior patella glide, and anterior patella translation were reduced by an average of 5.1 mm, 5.8 mm and 2.9 mm when quadriceps loading coincided with knee flexion rather than knee extension. These kinematic variations induced a distal shift in the finite helical axis of the tibiofemoral joint and a reduction in the patellar tendon moment arm. We conclude that it may be important to consider such load-dependent changes in knee kinematics when using models to ascertain soft tissue and cartilage loading during functional tasks such as gait. PMID:23806309

Westphal, Christopher; Schmitz, Anne; Reeder, Scott B.; Thelen, Darryl G.

2013-01-01

216

A novel multi-planar radiography method for three dimensional pose reconstruction of the patellofemoral and tibiofemoral joints after arthroplasty.  

PubMed

Determining the 3D pose of the patella after total knee arthroplasty is challenging. The commonly used single-plane fluoroscopy is prone to large errors in the clinically relevant mediolateral direction. A conventional fixed bi-planar setup is limited in the minimum angular distance between the imaging planes necessary for visualizing the patellar component, and requires a highly flexible setup to adjust for the subject-specific geometries. As an alternative solution, this study investigated the use of a novel multi-planar imaging setup that consists of a C-arm tracked by an external optoelectric tracking system, to acquire calibrated radiographs from multiple orientations. To determine the accuracies, a knee prosthesis was implanted on artificial bones and imaged in simulated 'Supine' and 'Weightbearing' configurations. The results were compared with measures from a coordinate measuring machine as the ground-truth reference. The weightbearing configuration was the preferred imaging direction with RMS errors of 0.48 mm and 1.32 ° for mediolateral shift and tilt of the patella, respectively, the two most clinically relevant measures. The 'imaging accuracies' of the system, defined as the accuracies in 3D reconstruction of a cylindrical ball bearing phantom (so as to avoid the influence of the shape and orientation of the imaging object), showed an order of magnitude (11.5 times) reduction in the out-of-plane RMS errors in comparison to single-plane fluoroscopy. With this new method, complete 3D pose of the patellofemoral and tibiofemoral joints during quasi-static activities can be determined with a many-fold (up to 8 times) (3.4mm) improvement in the out-of-plane accuracies compared to a conventional single-plane fluoroscopy setup. PMID:21536291

Amiri, Shahram; Wilson, David R; Masri, Bassam A; Sharma, Gulshan; Anglin, Carolyn

2011-06-01

217

Load-dependent variations in knee kinematics measured with dynamic MRI.  

PubMed

Subtle changes in knee kinematics may substantially alter cartilage contact patterns and moment generating capacities of soft tissues. The objective of this study was to use dynamic magnetic resonance imaging (MRI) to measure the influence of the timing of quadriceps loading on in vivo tibiofemoral and patellofemoral kinematics. We tested the hypothesis that load-dependent changes in knee kinematics would alter both the finite helical axis of the tibiofemoral joint and the moment arm of the patellar tendon. Eight healthy young adults were positioned supine in a MRI-compatible device that could impose either elastic or inertial loads on the lower leg in response to cyclic knee flexion-extension. The elastic loading condition induced concentric quadriceps contractions with knee extension, while an inertial loading condition induced eccentric quadriceps contractions with knee flexion. Peak internal knee extension moments ranged from 23 to 33 N m, which is comparable to loadings seen in normal walking. We found that anterior tibia translation, superior patella glide, and anterior patella translation were reduced by an average of 5.1, 5.7 and 2.9 mm when quadriceps loading coincided with knee flexion rather than knee extension. These kinematic variations induced a distal shift in the finite helical axis of the tibiofemoral joint and a reduction in the patellar tendon moment arm. We conclude that it may be important to consider such load-dependent changes in knee kinematics when using models to ascertain soft tissue and cartilage loading during functional tasks such as gait. PMID:23806309

Westphal, Christopher J; Schmitz, Anne; Reeder, Scott B; Thelen, Darryl G

2013-08-01

218

Prenatal Lead Exposure and Weight of 0- to 5-Year-Old Children in Mexico City  

PubMed Central

Background: Cumulative prenatal lead exposure, as measured by maternal bone lead burden, has been associated with smaller weight of offspring at birth and 1 month of age, but no study has examined whether this effect persists into early childhood. Objective: We investigated the association of perinatal maternal bone lead, a biomarker of cumulative prenatal lead exposure, with children’s attained weight over time from birth to 5 years of age. Methods: Children were weighed at birth and at several intervals up until 60 months. Maternal tibia and patella lead were measured at 1 month postpartum using in vivo K-shell X-ray fluorescence. We used varying coefficient models with random effects to assess the association of maternal bone lead with weight trajectories of 522 boys and 477 girls born between 1994 and 2005 in Mexico City. Results: After controlling for breast-feeding duration, maternal anthropometry, and sociodemographic characteristics, a 1-SD increase in maternal patella lead (micrograms per gram) was associated with a 130.9-g decrease in weight [95% confidence interval (CI), –227.4 to –34.4 g] among females and a 13.0-g nonsignificant increase in weight among males (95% CI, –73.7 to 99.9 g) at 5 years of age. These associations were similar after controlling for concurrent blood lead levels between birth and 5 years. Conclusions: Maternal bone lead was associated with lower weight over time among female but not male children up to 5 years of age. Given that the association was evident for patellar but not tibial lead levels, and was limited to females, results need to be confirmed in other studies. PMID:21715242

Peterson, Karen E.; Sánchez, Brisa N.; Cantonwine, David; Lamadrid-Figueroa, Héctor; Schnaas, Lourdes; Ettinger, Adrienne S.; Hernández-Avila, Mauricio; Hu, Howard; Téllez-Rojo, Martha M.

2011-01-01

219

The manipulation of strain, when stress is controlled, modulates in vivo tendon mechanical properties but not systemic TGF-?1 levels  

PubMed Central

Modulators of loading-induced in vivo adaptations in muscle–tendon complex (MTC) mechanical properties remain unclear. Similarly contentious, is whether changes in MTC characteristics are associated with growth factor levels. Four groups were subjected to varying magnitudes of stress/strain: Group 1 trained with the MTC at a shortened position (MTCS; n = 10); Group 2 at a lengthened position (MTCL; n = 11; stress levels matched to MTCS); Group 3 over a wide range of motion (MTCX; n = 11); and Group 4 (n = 10) was the control population (no training). Patella tendon Stiffness (P < 0.001), Young's modulus, and quadriceps torque (P < 0.05) increments (only seen in the training groups), showed MTCL and MTCX groups responses to be superior to those of MTCS (P < 0.05). In addition, MTCL and MTCX better maintained adaptations compared to MTCS (P < 0.05) following detraining, with a pattern of slower loss of improvements at the early phase of detraining in all training groups. There were no significant changes (P > 0.05) in antagonist cocontraction, patella tendon dimensions or circulating transforming growth factor beta (TGF-?1) levels following training or detraining in any of the groups. We conclude that chronically loading the MTC in a relatively lengthened position (which involves greater strains) enhances its mechanical properties, more so than loading in a shortened position. This is true even after normalizing for internal stress. The underlying endocrine mechanisms do not appear to be mediated via TGF-?1, at least not at the systemic level. Our findings have implications with regard to the effectiveness of eccentric loading on improved tendon structural and mechanical properties. PMID:24303165

McMahon, Gerard E; Morse, Christopher I; Burden, Adrian; Winwood, Keith; Onambélé-Pearson, Gladys L

2013-01-01

220

Anterior Knee Pain in Patients with Cerebral Palsy  

PubMed Central

Background The aim of this study was to identify the risk factors for anterior knee pain in patients with cerebral palsy. Methods This prospective study investigated the risk factors for anterior knee pain in 127 ambulatory patients with spastic cerebral palsy in terms of walking pain, resting pain, and provocative pain. Demographic data analysis and physical examination for measuring the knee flexion contracture and unilateral and bilateral popliteal angles were performed. Patellar height was measured on radiographs, and patella alta was identified. The risk factors for anterior knee pain were analyzed using multivariate analysis with a generalized estimating equation. Results Seventy-seven patients were found to have patella alta based on the radiographic measurements (60.6%). Overall, sixteen patients (12.6%) had either unilateral or bilateral anterior knee pain. Of these, 6 patients showed a visual analogue scale (VAS) ? 3, 9 patients showed 3 < VAS ? 7, and one patient showed a VAS > 7. Age was found to be a significant risk factor for walking pain and resting pain with odds ratios (ORs) of 1.08 (95% confidence interval [CI], 1.02 to 1.14) and 1.09 (95% CI, 1.03 to 1.15), respectively. In the multivariate analysis, knee flexion contracture was a significant protective factor with an OR of 0.92 (95% CI, 0.85 to 0.98). Conclusions Approximately 12.6% of ambulatory patients with spastic cerebral palsy were found to have anterior knee pain in our hospital-based cohort study. Age was found to be a significant risk factor for anterior knee pain while walking and resting. PMID:25436067

Choi, Young; Lee, Sang Hyeong; Chung, Chin Youb; Park, Moon Seok; Lee, Kyoung Min; Sung, Ki Hyuk; Won, Sung Hun; Lee, In Hyeok; Choi, In Ho; Cho, Tae-Joon; Yoo, Won Joon

2014-01-01

221

Clinical Outcomes of Patellar Chondral Lesions Treated with Juvenile Particulated Cartilage Allografts  

PubMed Central

Background Juvenile particulated cartilage allograft (DeNovo NT®, Zimmer, Warsaw, IN) transplantation is a relatively new technology for the treatment of high-grade cartilage lesions. To date there is limited literature demonstrating its effectiveness and safety. The present study specifically looks at the short-term efficacy of DeNovo NT® allograft for symptomatic high-grade cartilage lesions of the patella. Clinical outcomes and complications are reported. Methods Seventeen cases of DeNovo NT® allograft transplantation at our institution were retrospectively reviewed from 2010 to 2013. Thirteen patients had the procedure performed for patellar lesions and are included in the present study. A chart review was performed to record demographic data, surgical technique, and complications. In addition, we analyzed preoperative and postoperative KOOS outcome scores. Results The mean age was 22.5 years (range, 14 - 34), with 3 males and 10 females. Mean follow-up was 8.2 months (range, 0.67 - 32.7). Six of the patients had concomitant anteromedialization of the tibial tubercle. DeNovo NT® allograft transplantation resulted in improvement for each outcome measure used. Overall KOOS score significantly improved from a mean of 58.4+15.7 to 69.2+18.6 (P = 0.04). Improvement in KOOS subscales of pain, ADL, and symptoms all approached but did not reach statistical significance (P values between 0.05 and 0.10). There were no infections or hardware complications. Conclusions This series demonstrates that DeNovo NT® allograft transplantation for symptomatic high-grade cartilage lesions of the patella results in pain relief and improved outcomes in the short term. Further studies are needed to better evaluate this new technology. Level of Evidence: Level IV, therapeutic case series PMID:25328458

Buckwalter, JA; Bowman, GN; Albright, JP; Wolf, BR; Bollier, M

2014-01-01

222

Subject-specific evaluation of patellofemoral joint biomechanics during functional activity.  

PubMed

Patellofemoral joint pain is a common problem experienced by active adults. However, relatively little is known about patellofemoral joint load and its distribution across the medial and lateral facets of the patella. In this study, biomechanical experiments and computational modeling were used to study patellofemoral contact mechanics in four healthy adults during stair ambulation. Subject-specific anatomical and gait data were recorded using magnetic resonance imaging, dynamic X-ray fluoroscopy, video motion capture, and multiple force platforms. From these data, in vivo tibiofemoral joint kinematics and knee muscle forces were computed and then applied to a deformable finite-element model of the patellofemoral joint. The contact force acting on the lateral facet of the patella was 4-6 times higher than that acting on the medial facet. The peak average patellofemoral contact stresses were 8.2±1.0 MPa and 5.9±1.3 MPa for the lateral and medial patellar facets, respectively. Peak normal compressive stress and peak octahedral shear stress occurred near toe-off of the contralateral leg and were higher on the lateral facet than the medial facet; furthermore, the peak compressive stress (11.5±3.0 MPa) was higher than the peak octahedral shear stress (5.2±0.9 MPa). The dominant stress pattern on the lateral patellar facet corresponded well to the location of maximum cartilage thickness. Higher loading of the lateral facet is also consistent with the clinical observation that the lateral compartment of the patellofemoral joint is more prone to osteoarthritis than the medial compartment. Predicted cartilage contact stress maps near contralateral toe-off showed three distinctly different patterns: peak stresses located on the lateral patellar facet; peak stresses located centrally between the medial and lateral patellar facets; and peak stresses located superiorly on both the medial and lateral patellar facets. PMID:24998901

Akbarshahi, Massoud; Fernandez, Justin W; Schache, Anthony G; Pandy, Marcus G

2014-09-01

223

An analytical model to predict interstitial lubrication of cartilage in migrating contact areas  

PubMed Central

For nearly a century, articular cartilage has been known for its exceptional tribological properties. For nearly as long, there have been research efforts to elucidate the responsible mechanisms for application toward biomimetic bearing applications. It is now widely accepted that interstitial fluid pressurization is the primary mechanism responsible for the unusual lubrication and load bearing properties of cartilage. Although the biomechanics community has developed elegant mathematical theories describing the coupling of solid and fluid (biphasic) mechanics and its role in interstitial lubrication, quantitative gaps in our understanding of cartilage tribology have inhibited our ability to predict how tribological conditions and material properties impact tissue function. This paper presents an analytical model of the interstitial lubrication of biphasic materials under migrating contact conditions. Although finite element and other numerical models of cartilage mechanics exist, they typically neglect the important role of the collagen network and are limited to a specific set of input conditions, which limits general applicability. The simplified approach taken in this work aims to capture the broader underlying physics as a starting point for further model development. In agreement with existing literature, the model indicates that a large Peclet number, Pe, is necessary for effective interstitial lubrication. It also predicts that the tensile modulus must be large relative to the compressive modulus. This explains why hydrogels and other biphasic materials do not provide significant interstitial pressure under high Pe conditions. The model quantitatively agrees with in-situ measurements of interstitial load support and the results have interesting implications for tissue engineering and osteoarthritis problems. This paper suggests that a low tensile modulus (from chondromalacia or local collagen rupture after impact, for example) may disrupt interstitial pressurization, increase shear stresses, and activate a condition of progressive surface damage as a potential precursor of osteoarthritis. PMID:24275436

Moore, A.; Burris, D.L.

2013-01-01

224

An analytical model to predict interstitial lubrication of cartilage in migrating contact areas.  

PubMed

For nearly a century, articular cartilage has been known for its exceptional tribological properties. For nearly as long, there have been research efforts to elucidate the responsible mechanisms for application toward biomimetic bearing applications. It is now widely accepted that interstitial fluid pressurization is the primary mechanism responsible for the unusual lubrication and load bearing properties of cartilage. Although the biomechanics community has developed elegant mathematical theories describing the coupling of solid and fluid (biphasic) mechanics and its role in interstitial lubrication, quantitative gaps in our understanding of cartilage tribology have inhibited our ability to predict how tribological conditions and material properties impact tissue function. This paper presents an analytical model of the interstitial lubrication of biphasic materials under migrating contact conditions. Although finite element and other numerical models of cartilage mechanics exist, they typically neglect the important role of the collagen network and are limited to a specific set of input conditions, which limits general applicability. The simplified approach taken in this work aims to capture the broader underlying physics as a starting point for further model development. In agreement with existing literature, the model indicates that a large Peclet number, Pe, is necessary for effective interstitial lubrication. It also predicts that the tensile modulus must be large relative to the compressive modulus. This explains why hydrogels and other biphasic materials do not provide significant interstitial pressure under high Pe conditions. The model quantitatively agrees with in-situ measurements of interstitial load support and the results have interesting implications for tissue engineering and osteoarthritis problems. This paper suggests that a low tensile modulus (from chondromalacia or local collagen rupture after impact, for example) may disrupt interstitial pressurization, increase shear stresses, and activate a condition of progressive surface damage as a potential precursor of osteoarthritis. PMID:24275436

Moore, A C; Burris, D L

2014-01-01

225

Levels of lead in breast milk and their relation to maternal blood and bone lead levels at one month postpartum.  

PubMed Central

Despite the many well-recognized benefits of breast-feeding for both mothers and infants, detectable levels of lead in breast milk have been documented in population studies of women with no current environmental or occupational exposures. Mobilization of maternal bone lead stores has been suggested as a potential endogenous source of lead in breast milk. We measured lead in breast milk to quantify the relation between maternal blood and bone lead levels and breast-feeding status (exclusive vs. partial) among 310 lactating women in Mexico City, Mexico, at 1 month postpartum. Umbilical cord and maternal blood samples were collected at delivery. Maternal breast milk, blood, and bone lead levels were obtained at 1 month postpartum. Levels of lead in breast milk ranged from 0.21 to 8.02 microg/L (ppb), with a geometric mean (GM) of 1.1 microg/L; blood lead ranged from 1.8 to 29.9 microg/dL (GM = 8.4 microg/dL); bone lead ranged from < 1 to 67.2 microg/g bone mineral (patella) and from < 1 to 76.6 microg/g bone mineral (tibia) at 1 month postpartum. Breast milk lead was significantly correlated with umbilical cord lead [Spearman correlation coefficient (rS) = 0.36, p < 0.0001] and maternal blood lead (rS= 0.38, p < 0.0001) at delivery and with maternal blood lead (rS = 0.42, p < 0.0001) and patella lead (rS= 0.15, p < 0.01) at 1 month postpartum. Mother's age, years living in Mexico City, and use of lead-glazed ceramics, all predictive of cumulative lead exposure, were not significant predictors of breast milk lead levels. Adjusting for parity, daily dietary calcium intake (milligrams), infant weight change (grams), and breast-feeding status (exclusive or partial lactation), the estimated effect of an interquartile range (IQR) increase in blood lead (5.0 microg/dL) was associated with a 33% increase in breast milk lead [95% confidence interval (CI), 24 to 43%], whereas an IQR increase in patella lead (20 microg/g) was associated with a 14% increase in breast milk lead (95% CI, 5 to 25%). An IQR increase in tibia lead (12.0 microg/g) was associated with a 5% increase in breast milk lead (95% CI, -3% to 14%). Our results indicate that even among a population of women with relatively high lifetime exposure to lead, levels of lead in breast milk are low, influenced both by current lead exposure and by redistribution of bone lead accumulated from past environmental exposures. PMID:15175184

Ettinger, Adrienne S; Téllez-Rojo, Martha María; Amarasiriwardena, Chitra; González-Cossío, Teresa; Peterson, Karen E; Aro, Antonio; Hu, Howard; Hernández-Avila, Mauricio

2004-01-01

226

The TOPGAME-study: effectiveness of extracorporeal shockwave therapy in jumping athletes with patellar tendinopathy. Design of a randomised controlled trial  

PubMed Central

Background Patellar tendinopathy is a major problem for many athletes, especially those involved in jumping activities. Despite its frequency and negative impact on athletic careers, no evidence-based guidelines for management of this overuse injury exist. Since functional outcomes of conservative and surgical treatments remain suboptimal, new diagnostic and therapeutic strategies have to be developed and evaluated. Extracorporeal shockwave therapy (ESWT) appears to be a promising treatment in patients with chronic patellar tendinopathy. ESWT is most often applied after the known conservative treatments have failed. However, its effectiveness as primary therapy has not been studied in athletes who keep playing sports despite having patellar tendon pain. The aim of this study is to determine the effectiveness of ESWT in athletes with patellar tendinopathy who are still in training and competition. Methods/design The TOPGAME-study (Tendinopathy of Patella Groningen Amsterdam Maastricht ESWT) is a multicentre two-armed randomised controlled trial with blinded participants and outcome assessors, in which the effectiveness of patient-guided focussed ESWT treatment (compared to placebo ESWT) on pain reduction and recovery of function in athletes with patellar tendinopathy will be investigated. Participants are volleyball, handball and basketball players with symptoms of patellar tendinopathy for a minimum of 3 to a maximum duration of 12 months who are still able to train and compete. The intervention group receives three patient-guided focussed medium-energy density ESWT treatments without local anaesthesia at a weekly interval in the first half of the competition. The control group receives placebo treatment. The follow-up measurements take place 1, 12 and 22 weeks after the final ESWT or placebo treatment, when athletes are still in competition. Primary outcome measure is the VISA-P (Victorian Institute of Sport Assessment - patella) score. Data with regard to pain during function tests (jump tests and single-leg decline squat) and ultrasound characteristics are also collected. During the follow-up period participants also register pain, symptoms, sports participation, side effects of treatment and additional medical consumption in an internet-based diary. Discussion The TOPGAME-study is the first RCT to study the effectiveness of patient-guided ESWT in athletes with patellar tendinopathy who are still in training and competition. Trial registration Trial registration number NTR1408. PMID:20144188

2010-01-01

227

In vivo patellar kinematics during total knee arthroplasty.  

PubMed

Patellar maltracking after total knee arthroplasty often results in complications, including anterior knee pain, instability and impingement, and is therefore better resolved intraoperatively. Many factors can affect patellar kinematics during knee replacement, including component position, implant design, joint alignment, and soft tissue tensions. However, to our knowledge, the impact of arthroplasty on patellar kinematics has not been previously reported in vivo. A computer-assisted surgery (CAS) system was developed to measure the pre-arthroplasty patellar kinematics, display the distance between this path and the surface of the planned femoral component, and compare the post-arthroplasty path to the pre-arthroplasty path. Three surgeons from three centers used this CAS system to measure the in vivo pre- and post-arthroplasty kinematics of 18 patients. There was a small, but consistent, proximal shift in the tibial joint lines (mean: 4.2 mm), resulting in pseudo patella-baja, i.e., relatively more distal contact of the patella on the femoral component. This led to significant changes in proximodistal and anteroposterior patellar positioning as well as patellar flexion following arthroplasty (p < 0.008). Mediolateral shift, tilt and internal/external spin had the greatest magnitudes of change (mean: 4.1 mm, 4.6 degrees and 4.6 degrees, respectively) relative to their mean pre-arthroplasty ranges (averaging 2.1 mm, 5.8 degrees and 5.8 degrees, respectively); however, these changes were distributed almost equally medially and laterally, indicating no surgical bias in any one direction. Female patients had more lateral tilt on average than male patients throughout flexion (p < 0.004 post-arthroplasty, p < 0.03 pre-arthroplasty, in later flexion), as well as other kinematic differences; there may therefore be potential for improving overall kinematic results by focusing on gender differences during research, design and surgery. This study demonstrated the feasibility of using a CAS system to measure patellofemoral kinematics. Intraoperative awareness of patellar tracking, including knowledge of the tibiofemoral joint line, could have an impact on the surgical plan and thereby improve the postoperative outcome. PMID:19085237

Anglin, Carolyn; Ho, Karen C T; Briard, Jean-Louis; de Lambilly, Charles; Plaskos, Christopher; Nodwell, Eric; Stindel, Eric

2008-11-01

228

Below Knee Impact Responses using Cadaveric Specimens.  

PubMed

Knee injuries represent about 10% of all injuries suffered during car crashes. Efforts to assess the injury risk to the posterior cruciate ligament (PCL) have been based on a study available in the literature (Viano et al., 1978), in which only two of the five knees tested had PCL ruptures. The aims of the current study were to repeat the study with a higher number of samples, study the effects of other soft tissues on knee response, and assess the adequacy of the experimental setup for the identification of a PCL tolerance. A total of 14 knees were tested using a high-speed materials testing machine. Eight were intact knees (with the patella and all the muscular and ligamentous structures), three were PCL-only knees (patella and all the muscular and ligamentous structures other than the PCL removed), and the last three were PCL-only knees with the tibia protected from bending fracture. Of the eight intact knees tested, only one had PCL mid substance rupture, one had a partial articular fracture of the tibia below the plateau, and six had simple transverse fracture of the tibial metaphysis. Of the three PCL-only knees without tibial protection, one had PCL mid substance rupture, one had avulsion at the posterior intercondylar attachment point, and the last one had a simple oblique fracture of the tibial metaphysis. Of the three PCL only knees with tibia protection, two had PCL mid-substance ruptures and the third one had an avulsion at the tibial insertion site with partial articular fracture of the lateral plateau. Overall, the results of the current study were similar to those observed by Viano et al. (1978). The average displacement at failure for all PCL related injuries was 17.2+/-2.8 mm for the current study (n=6) and 16.2+/-3.9 mm for Viano et al. (1978) (n=4). This value is higher than the Injury Assessment Reference Value of 15 mm proposed by Mertz (1984) and used in various regulations. Both studies suggest that the existence of the soft tissues other than the PCL affect the injury outcome and that the intact knee would suffer predominantly tibial metaphyseal fractures possibly due to bending. Consequently, it is concluded that the current experimental setup can produce isolated PCL injuries but the data available are inadequate to characterize PCL tolerance. A Hybrid III knee equipped with a ball bearing knee slider was also tested using a pendulum setup. Apart from the initial higher stiffness, the overall response of this knee lies within the force-deflection corridors defined using the response of the cadaver knees with PCL mid-substance failure. PMID:17230262

Balasubramanian, Sriram; Beillas, Philippe; Belwadi, Aditya; Hardy, Warren N; Yang, King H; King, Albert I; Masuda, Mitsutoshi

2004-11-01

229

Simultaneous segmentation of the bone and cartilage surfaces of a knee joint in 3D  

NASA Astrophysics Data System (ADS)

We present a novel framework for the simultaneous segmentation of multiple interacting surfaces belonging to multiple mutually interacting objects. The method is a non-trivial extension of our previously reported optimal multi-surface segmentation. Considering an example application of knee-cartilage segmentation, the framework consists of the following main steps: 1) Shape model construction: Building a mean shape for each bone of the joint (femur, tibia, patella) from interactively segmented volumetric datasets. Using the resulting mean-shape model - identification of cartilage, non-cartilage, and transition areas on the mean-shape bone model surfaces. 2) Presegmentation: Employment of iterative optimal surface detection method to achieve approximate segmentation of individual bone surfaces. 3) Cross-object surface mapping: Detection of inter-bone equidistant separating sheets to help identify corresponding vertex pairs for all interacting surfaces. 4) Multi-object, multi-surface graph construction and final segmentation: Construction of a single multi-bone, multi-surface graph so that two surfaces (bone and cartilage) with zero and non-zero intervening distances can be detected for each bone of the joint, according to whether or not cartilage can be locally absent or present on the bone. To define inter-object relationships, corresponding vertex pairs identified using the separating sheets were interlinked in the graph. The graph optimization algorithm acted on the entire multiobject, multi-surface graph to yield a globally optimal solution. The segmentation framework was tested on 16 MR-DESS knee-joint datasets from the Osteoarthritis Initiative database. The average signed surface positioning error for the 6 detected surfaces ranged from 0.00 to 0.12 mm. When independently initialized, the signed reproducibility error of bone and cartilage segmentation ranged from 0.00 to 0.26 mm. The results showed that this framework provides robust, accurate, and reproducible segmentation of the knee joint bone and cartilage surfaces of the femur, tibia, and patella. As a general segmentation tool, the developed framework can be applied to a broad range of multi-object segmentation problems.

Yin, Y.; Zhang, X.; Anderson, D. D.; Brown, T. D.; Hofwegen, C. Van; Sonka, M.

2009-02-01

230

Use of a polymethacrylate radial head spacer in temporary reconstruction of complex radial head fracture with associated elbow instability.  

PubMed

Radial head replacement in complex elbow fractures (Mason III) with either bony or ligamentous injuries or interosseous membrane rupture is unquestionable. Actual modular and metallic prosthesis ease the mounting technique and ensure durability. Nevertheless, these types of prostheses are not always available in a short time in our daily practice. We present the use of a transient polymethacrylate spacer as an alternative in nonreconstructable complex radial head fractures with a unstable elbow. We assessed 38 patients between 2006 and 2007, with a median follow-up of 53.8 months. We included 14 Mason IV; 8 Monteggia (posterior); 7 Mason III with either associated medial collateral ligament or interosseous membrane injury; 6 elbow triads; and 3 Essex-Lopresti lesions. With the Mayo elbow performance score and the disabilities of the arm, shoulder, and hand score questionnaire, we assessed the functionality. Anatomic results were evaluated with x-ray scans of the elbow and wrist using the Broberg and Morrey and the Knirk and Jupiter scales. Functional results were as follows: 14--excellent, 14--good, 8--fair, and 2--poor. Assessment through disabilities of the arm, shoulder, and hand score questionnaire was 18.7% in average. There was a statistically significant relationship between joint stability and motion. Of the patients, 70% showed mild or moderate chondromalacia of the capitellum and 90% showed osteolysis on the proximal metaphysis of the radius, both events related to follow-up time but not to pain or range of movement. Of the cases, 30% showed heterotopic calcifications and 35% showed moderate arthrosis between the ulna and the humerus. None of the patients presented wrist arthrosis. Complications were 1 deep infection and 1 spacer luxation because of fatigue and ulna plate rupture (Monteggia posterior). In 6 patients, we had to remove the spacer because of pain and/or functional limitation, and 2 of these patients remained with moderate valgus instability after removal. We consider using this type of spacer in those complex situations in which the definitive prosthesis is not available, because it is cheap and resistant to axial and valgus forces. In spite of the good anatomic and functional results obtained and the low complication rate, we firmly think that the spacer should only be used in a transient manner and in special situations, although in this series, only 8 of the 38 patients have accepted to have the spacer removed. PMID:21107226

Capomassi, Miguel Angel; Clembosky, Gabriel Adrián

2010-12-01

231

How reliable is MRI in diagnosing cartilaginous lesions in patients with first and recurrent lateral patellar dislocations?  

PubMed Central

Background Lateral dislocation of the patella (LPD) leads to cartilaginous injuries, which have been reported to be associated with retropatellar complaints and the development of patellofemoral osteoarthritis. Therefore, the purpose of this study was to determine the reliability of MRI for cartilage diagnostics after a first and recurrent LPD. Methods After an average of 4.7 days following an acute LPD, 40 patients (21 with first LPDs and 19 with recurrent LPDs) underwent standardized 1.5 Tesla MRI (sagittal T1-TSE, coronal STIR-TSE, transversal fat-suppressed PD-TSE, sagittal fat-suppressed PD-TSE). MRI grading was compared to arthroscopic assessment of the cartilage. Results Sensitivities and positive predictive values for grade 3 and 4 lesions were markedly higher in the patient group with first LPDs compared to the group with recurrent LPDs. Similarly, intra- and inter-observer agreement yielded higher kappa values in patients with first LPDs compared to those with recurrent LPDs. All grade 4 lesions affecting the subchondral bone (osteochondral defects), such as a fissuring or erosion, were correctly assessed on MRI. Conclusions This study demonstrated a comparatively good diagnostic performance for MRI in the evaluation of first and recurrent LPDs, and we therefore recommend MRI for the cartilage assessment after a LPD. PMID:20602779

2010-01-01

232

The young osteoarthritic knee: dilemmas in management  

PubMed Central

As a result of increasing life expectancies, continuing physical careers, lifestyles into later life and rising obesity levels, the number of younger patients presenting with osteoarthritis (OA) of the knee is increasing. When conservative management options have been exhausted, the challenge for the orthopedic surgeon is to offer a procedure that will relieve symptoms and allow a return to a high level of function but not compromise future surgery that may be required as disease progresses or prostheses fail and require revision. We discuss the options available to this group of patients and the relative benefits and potential negative points of each. Total knee replacement (TKR) in the young patient is associated with high risk of early failure and the need for future revision surgery. After TKR, most surgeons advise limitation of sporting activities. If osteoarthritis is limited to only one compartment in the knee there may be surgical options other than TKR. Osteotomy above or below the knee may be considered and works by redirecting the load passing through the joint into the relatively unaffected compartment. A unicompartmental knee replacement (UKR) or patella-femoral joint (PFJ) replacement only replaces the articular surfaces in the affected compartment, leaving the unaffected compartments untouched with better preservation of the soft tissues. Which of these options is best for a particular patient depends upon the patient's symptoms, precise pathology, lifestyle, and expectations. PMID:23331908

2013-01-01

233

Stress Fractures of the Pelvis and Legs in Athletes  

PubMed Central

Context: Stress fractures are common injuries in athletes, often difficult to diagnose. A stress fracture is a fatigue-induced fracture of bone caused by repeated applications of stress over time. Evidence Acquisition: PubMed articles published from 1974 to January 2012. Results: Intrinsic and extrinsic factors may predict the risk of stress fractures in athletes, including bone health, training, nutrition, and biomechanical factors. Based on their location, stress fractures may be categorized as low- or high-risk, depending on the likelihood of the injury developing into a complete fracture. Treatment for these injuries varies substantially and must account for the risk level of the fractured bone, the stage of fracture development, and the needs of the patient. High-risk fractures include the anterior tibia, lateral femoral neck, patella, medial malleolus, and femoral head. Low-risk fractures include the posteromedial tibia, fibula, medial femoral shaft, and pelvis. Magnetic resonance is the imaging test of choice for diagnosis. Conclusions: These injuries can lead to substantial lost time from participation. Treatment will vary by fracture location, but most stress fractures will heal with rest and modified weightbearing. Some may require more aggressive intervention, such as prolonged nonweightbearing movement or surgery. Contributing factors should also be addressed prior to return to sports. PMID:24427386

Behrens, Steve B.; Deren, Matthew E.; Matson, Andrew; Fadale, Paul D.; Monchik, Keith O.

2013-01-01

234

Limpets counteract ocean acidification induced shell corrosion by thickening of aragonitic shell layers  

NASA Astrophysics Data System (ADS)

Specimens of the patellogastropod limpet Patella caerulea were collected within (pHlow-shells) and outside (pHn-shells) a CO2 vent site at Ischia, Italy. Four pHlow-shells and four pHn-shells were sectioned transversally and scanned for polymorph distribution by means of confocal Raman microscopy. The pHlow-shells displayed a twofold increase in aragonite area fraction and size normalised aragonite area. Size normalised calcite area was halved in pHlow-shells. Taken together with the increased apical and the decreased flank size normalised thickness of the pHlow-shells, these data led us to conclude that low pH exposed P. caerulea specimens counteract shell dissolution by enhanced shell production. The latter is different from normal elongation growth and proceeds through addition of aragonitic layers only, while the production of calcitic layers is confined to elongation growth. Therefore aragonite cannot be regarded as a per se disadvantageous polymorph under ocean acidification conditions.

Langer, G.; Nehrke, G.; Baggini, C.; Rodolfo-Metalpa, R.; Hall-Spencer, J.; Bijma, J.

2014-08-01

235

Effects of Open and Closed Kinetic Chains of Sling Exercise Therapy on the Muscle Activity of the Vastus Medialis Oblique and Vastus Lateralis  

PubMed Central

[Purpose] The muscle strength of the quadriceps muscle is critical in patellofemoral pain syndrome. The quadriceps muscle supplies the power for dynamic patellar movement, and the vastus medialis oblique (VMO) and vastus lateralis (VL) enable the patella to stabilize during tracking. We followed the theories about open and closed kinetic chain exercises to design two exercises, sling open chain knee extension (SOCKE) exercise and sling closed chain knee extension (SCCKE) exercise. The purpose of our study was to research the changes in quadriceps muscle activity during both exercises. [Methods] Electromyographic analysis was used to explore the different effects of the two exercises. The MVC% was calculated for the VMO and VL during exercise for analysis. [Results] We found that the mean MVC% values of the VMO and VL during the SOCKE exercise were higher than those during the SCCKE exercise. The ratio of the VMO to VL was 1.0 ± 0.19 during the SOCKE exercise and 1.11 ± 0.15 during the SCCKE exercise. [Conclusions] The SOCKE exercise is targeted at quadriceps muscle training and has a recruitment effect on the VMO. The beneficial effect of the SOCKE exercise is better than that of the SCCKE exercise. PMID:25276016

Chang, Wen-Dien; Huang, Wei-Syuan; Lee, Chia-Lun; Lin, Hung-Yu; Lai, Ping-Tung

2014-01-01

236

T2 relaxation time measurements are limited in monitoring progression, once advanced cartilage defects at the knee occur  

PubMed Central

Purpose To study the natural evolution of cartilage T2 relaxation times in knees with various extents of morphological cartilage abnormalities, assessed with 3T MRI from the Osteoarthritis Initiative. Materials and Methods Right knee MRIs of 245, 45–60 year old individuals without radiographic OA were included. Cartilage was segmented and T2 maps were generated in five compartments (patella, medial and lateral femoral condyle, medial and lateral tibia) at baseline and two-year follow-up. We examined the association of T2 values and two-year change of T2 values with various Whole-Organ MR Imaging Scores (WORMS). Statistical analysis was performed with ANOVA and Students t-tests. Results Higher baseline T2 was associated with more severe cartilage defects at baseline and subsequent cartilage loss (P<0.001). However, longitudinal T2 change was inversely associated with both baseline (P=0.038) and follow-up (P=0.002) severity of cartilage defects. Knees that developed new cartilage defects had smaller increases in T2 than subjects without defects (P=0.045). Individuals with higher baseline T2 showed smaller T2 increases over time (P<0.001). Conclusion An inverse correlation of longitudinal T2 changes versus baseline T2 values and morphological cartilage abnormalities suggests that once morphological cartilage defects occur, T2 values may be limited for evaluating further cartilage degradation. PMID:24038491

Jungmann, P.M.; Kraus, M.S.; Nardo, L.; Liebl, H.; Alizai, H.; Joseph, G.B.; Liu, F.; Lynch, J.; McCulloch, C.E.; Nevitt, M.C.; Link, T.M.

2014-01-01

237

The Use of Patellar Taping in the Treatment of a Patient with a Medial Collateral Ligament Sprain  

PubMed Central

Background The medial collateral ligament (MCL) is one of the most frequently injured ligaments in the knee. The purpose of this case report is to describe conservative management of a 13 year-old soccer player with a one year history of untreated intermittent bilateral anterior knee pain who sustained a grade II MCL sprain while playing soccer and returned to competitive play within four weeks. The use of patellar taping as an adjunct to treatment will be introduced. Case Description Based on the physical examination findings, the patient's injury was classified as a grade II MCL sprain. The patient was treated successfully with a combination of modalities, manual therapy, and therapeutic exercise. Specifically, patellar taping was added to the traditional physical therapy regimen. Pain scale ratings, strength assessment, and a variety of functional outcome assessment tools were used to determine progression and outcomes. Outcomes Following one session of modalities, manual therapy, patellar taping, and education in a home exercise program (HEP), the patient reported decreased overall left knee pain and increased comfort with knee active range of motion (AROM). Throughout the four weeks of treatment, the patient was compliant with the HEP. During this time, the patient continued to demonstrate improvement in pain, strength, AROM, and functional activities. Upon discharge, the patient was cleared for full return to sports. Discussion The novel intervention in this case report was the taping of the patella medially. This patient returned to sports two weeks earlier than the average athlete with a grade II MCL sprain. PMID:21509111

Masaracchio, Michael

2009-01-01

238

Limpets counteract ocean acidification induced shell corrosion by thickening of aragonitic shell layers  

NASA Astrophysics Data System (ADS)

Specimens of the patellogastropod limpet Patella caerulea were collected within (pHlow-shells) and outside (pHn-shells) a CO2 vent site at Ischia, Italy. Four pHlow-shells and four pHn-shells were sectioned transversally and scanned for polymorph distribution by means of confocal Raman microscopy. The pHlow-shells displayed a twofold increase in aragonite area fraction and size-normalised aragonite area. Size-normalised calcite area was halved in pHlow-shells. Taken together with the increased apical and the decreased flank size-normalised thickness of the pHlow-shells, these data led us to conclude that low-pH-exposed P. caerulea specimens counteract shell dissolution by enhanced shell production. This is different from normal elongation growth and proceeds through addition of aragonitic parts only, while the production of calcitic parts is confined to elongation growth. Therefore, aragonite cannot be regarded as a disadvantageous polymorph per se under ocean acidification conditions.

Langer, G.; Nehrke, G.; Baggini, C.; Rodolfo-Metalpa, R.; Hall-Spencer, J. M.; Bijma, J.

2014-12-01

239

Successful treatment with low-dose thalidomide in a patient with both Behçet's disease and complex regional pain syndrome type I: case report.  

PubMed

Thalidomide is a recognized treatment of Behçet's disease. Low-dose thalidomide seems to be effective in the treatment of orogenital ulcers and is potentially safer with a lower incidence of adverse effects than higher doses. We wish to report a case of Behçet's disease in a 33-year-old woman who responded well to thalidomide 50 mg 2 to 4 times per week. Her disease manifestations (severe orogenital ulceration, pseudofolliculitis, mild thrombophlebitis, positive pathergy response, and fatigue) were previously resistant to courses of prednisone, dapsone, colchicine, various types of mouthwash, and topical steroid preparations. She also gave a history of complex regional pain syndrome type I (CRPS 1) over her left patella (severe pain, intermittent edema, hyperalgesia, allodynia, cold skin, and loss of movement) after a fall onto her left knee 6 years previously. This had only partially responded to a variety of treatment modalities. After starting thalidomide for her Behçet's disease, the pain in her left knee unexpectedly disappeared. There are rat experiments showing that thalidomide improves neuropathic pain, probably by selectively blocking tumor necrosis factor-alpha production in activated macrophages. We believe this is the first report of successful use of thalidomide in a human being with CRPS 1, and we therefore recommend that thalidomide should be considered in the treatment of CRPS 1. PMID:17041438

Ching, Daniel W T; McClintock, Alan; Beswick, Frances

2003-04-01

240

Protoporphyrin IX distribution after intra-articular and systemic application of 5-aminolevulinic acid in healthy and arthritic joints  

NASA Astrophysics Data System (ADS)

Arthroscopic synovectomy, which is limited today to the large joints, is an important early treatment of rheumatoid arthritis (RA). Photodynamic therapy (PDT) is potentially to be a less invasive method of removing the synovial membrane. Therefore, in a rabbit model of RA, the accumulation of the photosensitizer Protoporphyrin IX (PPIX) after intra-articular and systemic application of ALA into arthritic rabbit knee joints was studied in skin, patella, synovial tissue, and meniscus by fluorescence microscopy. PPIX fluorescence was measured in biopsies taken at different times after application of neutral and acid ALA solutions. Significant PPIX fluorescence was observed in the synovial membrane and skin 2 and 4 hours after application. Using intra-articular application, ALA solutions prepared with pH 5.5 were at least as efficient as neutral solutions in sensitizing the synovial membrane. Skin also showed PPIX within 4 hours after application. After 24 hours, a marginal PPIX fluorescence was detected in these tissues. On the other hand, in cartilage and meniscus significant PPIX accumulation was still observed 24 hours after ALA injection. Systemic application of ALA also showed a good accumulation of PPIX. Further experiments are needed to show whether accumulation of the photosensitizer and tissue selectivity are sufficient for a successful treatment of rheumatoid synovitis.

Huettmann, Gereon; Hendrich, Christian; Birngruber, Reginald; Lehnert, Christiane; Seara, Jose; Siebert, Werner E.; Diddens, Heyke C.

1996-04-01

241

Greater Trochanter Apophysitis in the Adolescent Athlete.  

PubMed

: Lower limb traction apophysitis is common in young athletes, occurring at sites such as the tibial tubercle (Osgood-Schlatter disease) and distal patella (Sinding-Larsen-Johansson disease). Around the hip, iliac apophysitis is well recognized, but no cases of greater trochanter apophysitis have previously been reported. We describe the case of a 15-year-old male basketball player with a 2-month history of the right hip pain and significant functional limitation. X-rays revealed widening of the greater trochanter apophysis with subchondral sclerosis, consistent with a diagnosis of traction apophysitis. The patient was treated with a period of relative rest and anti-inflammatory medication. He gradually returned to full athletic activity, including basketball, without recurrence of pain or limitation. We describe the first reported case of traction apophysitis of the greater trochanter. The unique muscular anatomy of this apophysis with balanced forces explains the rarity of this condition. If encountered, rest and activity modification is the recommended treatment. PMID:24942622

Young, Simon W; Safran, Marc R

2014-06-17

242

Bioabsorbable expansion bolt fixation in anterior cruciate ligament reconstruction.  

PubMed

The current study evaluated initial fixation strength of a bioabsorbable expansion bolt compared with interference screw fixation in anterior cruciate ligament reconstruction using a bone-patellar tendon-bone graft. Thirty calf tibial plateaus with adjacent patella and extensor ligaments were used. Bioabsorbable poly-L-lactide interference screws were used for graft fixation in Group I, titanium screws in Group II, and bioabsorbable poly-DL-lactide expansion bolts were used in Group III. The mean force-to-failure (+/- standard deviation) in the three groups was 487 +/- 205 N, 713 +/- 218 N, and 594 +/- 224 N, respectively. The differences between Groups I and II were significant. No statistical differences were found regarding stiffness. Graft damage was significantly less in Group III compared with screw fixation. The fixation concept of an expansion bolt shows similar fixation strength and less graft damage compared with the established interference screw fixation. Because of the total absence of torque forces in contrast to bioabsorbable screws, the risk of implant breakage is minimized. PMID:15043122

Piltz, S; Steinbauer, T; Meyer, L; Plitz, W; Andress, H J; Lob, G

2004-01-01

243

Biomechanical testing of implant free wedge shaped bone block fixation for bone patellar tendon bone anterior cruciate ligament reconstruction in a bovine model  

PubMed Central

Background The use of an interference fit wedged bone plug to provide fixation in the tibial tunnel when using bone-patellar tendon-bone autograft for anterior cruciate ligament reconstruction offers many theoretic advantages including the potential to offer a more economical and biological alternative to screw fixation. This technique has not been subjected to biomechanical testing. We hypothesised that a wedged bone plug fixation technique provides equivalent tensile load to failure as titanium interference screw fixation. Methods In a controlled laboratory setting, anterior cruciate ligament reconstruction was performed in 36 bovine knees using bone-patella-bone autograft. In 20 knees tibial fixation relied upon a standard cuboid bone block and interference screw. In eight knees a wedge shaped bone block with an 11 mm by 10 mm base without a screw was used. In a further eight knees a similar wedge with a 13 mm by 10 mm base was used. Each specimen used a standard 10 mm tibial tunnel. The reconstructions were tested biomechanically in a physiological environment using an Instron machine to compare ultimate failure loads and modes of failure. Results Statistical analysis revealed no significant difference between wedge fixation and screw fixation (p = 0.16), or between individual groups (interference screw versus 11 mm versus 13 mm wedge fixation) (P = 0.35). Conclusions Tibial tunnel fixation using an impacted wedge shaped bone block in anterior cruciate ligament reconstruction has comparable ultimate tensile strength to titanium interference screw fixation. PMID:20813059

2010-01-01

244

Surgical procedures and experimental outcomes of closed fractures in rodent models.  

PubMed

The closed fracture rat model, first described by Bonnarens and Einhorn, has been widely implemented in recent years to characterize various fracture phenotypes and evaluate treatment modalities. Slight modifications in the fixation depth, to reduce surgical error associated with movement/dislocation of the k-wire fixation, were previously described. Here, we describe this method which involves the creation of a medial parapatellar incision, dislocation of the patella, boring an 18 gauge hole through the center of the femur, delivery of an adjunct (if applicable), fixation of the k-wire in the greater trochanter of the femur, suturing of muscle and skin, and finally creation of the mid-diaphyseal fracture with a three-point bending fracture device. Many laboratories routinely perform surgical procedures in which a closed fracture is induced using rat or mouse models. The benefits of such surgical models range from general orthopaedic trauma applications to the assessment of the healing process in genetically modified animals. Other important applications include the assessment of the safety and efficacy of various treatment modalities as well as the characterization of bone repair in metabolic bone diseases or skeletal dysplasia. PMID:25331052

Drissi, Hicham; Paglia, David N

2015-01-01

245

Brefeldin A or monensin inhibits the 3D organizer in gastropod, polyplacophoran, and scaphopod molluscs.  

PubMed

In molluscs, the 3D vegetal blastomere acts as a developmental signaling center, or organizer, and is required to establish bilateral symmetry in the embryo. 3D is similar to organizing centers in other metazoans, but detailed comparisons are difficult, in part because its organizing function is poorly understood. To elucidate 3D function in a standardized fashion, we used monensin and brefeldin A (BFA) to rapidly and reversibly interfere with protein processing and secretion, thereby inhibiting the signaling interactions that underlie its specification and patterning. In the gastropods, Patella vulgata and Lymnaea stagnalis, the polyplacophoran, Mopalia muscosa, and the scaphopod, Antalis entalis, treatments initiated before the organizer-dependent onset of bilateral cleavage resulted in radialization of subsequent development. In radialized P. vulgata, L. stagnalis, and M. muscosa, organizer specification was blocked, and embryos failed to make the transition to bilateral cleavage. In all four species, the subsequent body plan was radially symmetric and was similarly organized about a novel aboral-oral axis. Our results demonstrate that brefeldin A (BFA) and monensin can be used to inhibit 3D's organizing function in a comparative fashion and that, at least in M. muscosa, the organizer-dependent developmental architecture of the embryo predicts subsequent patterns of morphogenetic movements in gastrulation and, ultimately, the layout of the adult body plan. PMID:17120024

Gonzales, Eric E; van der Zee, Maurijn; Dictus, Wim J A G; van den Biggelaar, Jo

2007-02-01

246

Relationships between Algae, Benthic Herbivorous Invertebrates and Fishes in Rocky Sublittoral Communities of a Temperate Sea (Mediterranean)  

NASA Astrophysics Data System (ADS)

In situ surveys were used to examine the contribution of benthic herbivorous invertebrates and fishes to the organization of Mediterranean rocky sublittoral communities. Shallow (1-3 m) and deep (6-8 m) sampling sites, in natural areas and on man-made structures, were characterized by a structural complexity index (cavity index and mean size of cavity aperture), algal cover (encrusting, turfy, shrubby and arborescent algae) and the density of benthic herbivorous invertebrates and fish. A relationship between structural complexity and biota was only evident for some fish species ( Diplodus spp. and Sarpa salpa) at deep sites, where they not only feed but also shelter. Three benthic herbivorous invertebrates, the sea urchins Paracentrotus lividus and Arbacia lixula, and the limpet Patella caerulea , are associated with communities dominated by encrusting algae. Variations in their abundance and role in structuring algal communities follow a depth gradient: P. caerulea and A. lixula are mainly present at shallow sites and P. lividus at deep sites. These benthic herbivorous invertebrates may account for the structure of shallow algal communities. In contrast, at deep sites, fishes (the omnivorous Diplodus spp. and the herbivorous S. salpa) have a potential importance in controlling sublittoral algae, in addition to invertebrates. It is suggested that the ecological impact of herbivorous and omnivorous fishes in temperate seas could be greater than is generally thought. Experiments should be designed to validate this postulate.

Ruitton, S.; Francour, P.; Boudouresque, C. F.

2000-02-01

247

Hip abduction can prevent posterior edge loading of hip replacements.  

PubMed

Edge loading causes clinical problems for hard-on-hard hip replacements, and edge loading wear scars are present on the majority of retrieved components. We asked the question: are the lines of action of hip joint muscles such that edge loading can occur in a well-designed, well-positioned acetabular cup? A musculoskeletal model, based on cadaveric lower limb geometry, was used to calculate for each muscle, in every position within the complete range of motion, whether its contraction would safely pull the femoral head into the cup or contribute to edge loading. The results show that all the muscles that insert into the distal femur, patella, or tibia could cause edge loading of a well-positioned cup when the hip is in deep flexion. Patients frequently use distally inserting muscles for movements requiring deep hip flexion, such as sit-to-stand. Importantly, the results, which are supported by in vivo data and clinical findings, also show that risk of edge loading is dramatically reduced by combining deep hip flexion with hip abduction. Patients, including those with sub-optimally positioned cups, may be able to reduce the prevalence of edge loading by rising from chairs or stooping with the hip abducted. PMID:23575923

van Arkel, Richard J; Modenese, Luca; Phillips, Andrew T M; Jeffers, Jonathan R T

2013-08-01

248

SLC26A2 disease spectrum in Sweden - high frequency of recessive multiple epiphyseal dysplasia (rMED).  

PubMed

Diastrophic dysplasia (DTD) is an autosomal recessive skeletal dysplasia caused by SLC26A2 mutations. Clinical features include short stature, joint contractures, spinal deformities, and cleft palate. SLC26A2 mutations also result in other skeletal dysplasias, including the milder recessive multiple epiphyseal dysplasia (rMED). DTD is overrepresented in Finland and we speculated that this may have influenced the prevalence and spectrum of SLC26A2-related skeletal conditions also in Sweden. We reviewed the patient registry at Department of Clinical Genetics, Karolinska University Hospital, Stockholm to identify subjects with SLC26A2 mutations. Seven patients from six families were identified; clinical data were available for six patients. All but one patient had one or two copies of the Finnish SLC26A2 founder mutation IVS1+2T>C. Arg279Trp mutation was present in compound heterozygous form in five patients with phenotypes consistent with rMED. Their heights ranged from -2.6 to -1.4 standard deviation units below normal mean and radiographic features included generalised epiphyseal dysplasia and double-layered patellae. Two rMED patients had hypoplastic C2 and cervical kyphosis, a severe manifestation previously described only in DTD. Our study confirms a high prevalence of rMED in Sweden and expands the phenotypic manifestations of rMED. PMID:24598000

Mäkitie, O; Geiberger, S; Horemuzova, E; Hagenäs, L; Moström, E; Nordenskjöld, M; Grigelioniene, G; Nordgren, A

2015-03-01

249

Manual Khalifa Therapy in Patients with Completely Ruptured Anterior Cruciate Ligament in the Knee: First Results from Near-Infrared Spectroscopy  

PubMed Central

Background: Manual Khalifa therapy has been practiced in Hallein, Austria, for more than 30 years; however, there are no scientific results available on the topic. Aims: The goal of the present study was to investigate possible acute effects of Khalifa therapy on regional oxygen saturation of knee tissues in patients with completely ruptured anterior cruciate ligament. Materials and Methods: We investigated 10 male patients (mean age ± standard deviation (SD) 35.9 ± 6.1 year) using a four-channel oximeter. The sensors were applied anterolaterally and anteromedially, beside the patella, on both the injured and the healthy (control) knee. Results: The results of the controlled study showed that values of oxygen saturation on the knee with the ruptured ligament were significantly increased (P < 0.001) immediately after Khalifa therapy, whereas the values on the control knee showed insignificant increases. Baselines values of the anterolateral side of the injured knee were significantly (P < 0.001) different from those of the anterolateral side of the control knee. The same effect was present on the anteromedial side; however, with a lower degree of significance (P < 0.05). Conclusions: Khalifa therapy was clinically successful in all 10 patients. Further, investigations and analyzes are necessary to explain the underlying mechanism. PMID:23814763

Litscher, Gerhard; Ofner, Michael; Litscher, Daniela

2013-01-01

250

The genera Anafroptilum Kluge, 2011 and Neocloeon Traver, 1932, reinstated status, in North America, with remarks about the global composition of Centroptilum Eaton, 1869 (Ephemeroptera: Baetidae).  

PubMed

The mayfly genus Centroptilum Eaton, 1869, s.s., (Ephemeroptera: Baetidae), as presently understood, is not known to occur in North America. Nearctic species recently classified there belong either to Anafroptilum Kluge, 2011 or to Neocloeon Traver, 1932, reinstated genus. The North American endemic Neocloeon differs fundamentally from Anafroptilum in that it possesses a patella-tibial suture on the foreleg of larvae and female adults, a characteristic that is shared with certain other baetid genera. Neocloeon includes the obligate parthenogen N. triangulifer, new combination, and a sexual species, N. alamance, reinstated combination. Nearctic Anafroptilum include: A. album (McDunnough, 1926), new combination, A. asperatum (Traver, 1935), new combination, A. bifurcatum (McDunnough, 1924), A. conturbatum (McDunnough, 1929), new combination, A. minor (McDunnough, 1926), new combination, A. ozarkense (Wiersema & Burian, 2000), new combination, A. semirufum (McDunnough, 1926), new combination, and A. victoriae (McDunnough, 1938), new combination. Further study will be required to determine the species composition of Anafroptilum and Centroptilum, s.s., in the Palearctic and Oriental realms. Anafroptilum and Neocloeon are part of the Cloeon complex of genera, but Centroptilum, s.s., is not. PMID:24943435

Jacobus, Luke M; Wiersema, N A

2014-01-01

251

Computer-assisted analysis of ligament constraints in the knee.  

PubMed

A computer graphics technique was employed to investigate the ligament constraints in the knee joint. A computer-assisted tomography scan system was employed to obtain the geometry of the knee and the ligament insertion locations. A cadaver knee was mounted in a special rig that kept the femur and the tibia in a specified position. The scans of the knee at 5-mm distances were recorded. These scans were projected in the computer to generate a data base for the tibia, the femur, and the tibial and femoral insertion locations for the various ligaments. The computer graphics analysis provides realistic views of the bone structures. The views compare favorably with the original CT scans. Interestingly, the scans near the ligament insertion site were clearly observed to have a higher bone density. Higher density was also observed at the intercondylar notch below the patella. The analysis was used to simulate ACL and PCL insufficiencies. A Lachman test at 25 degrees of flexion is a sensitive test for ACL insufficiency, whereas the 90 degrees drawer test may not be a sensitive indicator of PCL insufficiency. This computer graphics technique may prove useful in the design and development of artificial ligaments as well as in planning surgical procedures. PMID:3995834

Langrana, N A; Bronfeld, J

1985-06-01

252

Lower limb joint replacement in rheumatoid arthritis  

PubMed Central

Introduction There is limited literature regarding the peri-operative and surgical management of patients with rheumatoid disease undergoing lower limb arthroplasty. This review article summarises factors involved in the peri-operative management of major lower limb arthroplasty surgery for patients with rheumatoid arthritis. Methods We performed a search of the medical literature, using the PubMed search engine (http://www.pubmed.gov). We used the following terms: ‘rheumatoid’ ‘replacement’ ‘arthroplasty’ and ‘outcome’. Findings The patient should be optimised pre-operatively using a multidisciplinary approach. The continued use of methotrexate does not increase infection risk, and aids recovery. Biologic agents should be stopped pre-operatively due the increased infection rate. Patients should be made aware of the increased risk of infection and periprosthetic fracture rates associated with their disease. The surgical sequence is commonly hip, knee and then ankle. Cemented total hip replacement (THR) and total knee replacement (TKR) have superior survival rates over uncemented components. The evidence is not clear regarding a cruciate sacrificing versus retaining in TKR, but a cruciate sacrificing component limits the risk early instability and potential revision. Patella resurfacing as part of a TKR is associated with improved outcomes. The results of total ankle replacement remain inferior to THR and TKR. RA patients achieve equivalent pain relief, but their rehabilitation is slower and their functional outcome is not as good. However, the key to managing these complicated patients is to work as part of a multidisciplinary team to optimise their outcome. PMID:22697352

2012-01-01

253

Evaluation of the Marsh Deer Stifle Joint by Imaging Studies and Gross Anatomy.  

PubMed

This study aimed to evaluate the stifle joint of marsh deer using imaging studies and in comparison with gross anatomy. Ten hindlimbs from 5 marsh deer (Blastocerus dichotomus) were used. Radiography, computed tomography (CT) and magnetic resonance imaging (MRI) were performed in each stifle joint. Two hindlimbs were dissected to describe stifle gross anatomy. The other limbs were sectioned in sagittal, dorsal or transverse planes. In the craniocaudal radiographic view, the lateral femoral condyle was broader than the medial femoral condyle. The femoral trochlea was asymmetrical. Subsequent multiplanar reconstruction revealed in the cranial view that the external surface of the patella was roughened, the medial trochlea ridge was larger than the lateral one, and the extensor fossa at the lateral condyle was next to the lateral ridge. The popliteal fossa was better visualized via the lateral view. Sagittal MRI images identified lateral and medial menisci, caudolateral and craniomedial bundles of cranial cruciate ligament, caudal cruciate ligament, patellar ligament and common extensor tendon. In conclusion, the marsh deer stifle presents some anatomical characteristics of the ovine stifle joint. PMID:25376635

Shigue, D A; Rahal, S C; Schimming, B C; Santos, R R; Vulcano, L C; Linardi, J L; Teixeira, C R

2014-11-01

254

Reconstruction of knee joint soft tissue and patellar tendon defects using a composite anterolateral thigh flap with vascularized fascia lata.  

PubMed

Reconstruction of a complex knee trauma with knee joint exposure and composite soft tissue and patellar tendon deficiency remains a challenging task. Multiple-stage reconstruction is time-consuming and produces considerable suffering for patients. Early mobilization following knee reconstruction has achieved good outcomes. Herein, we reported one-stage reconstruction with an ALT myocutaneous flap with vascularized fascia lata was utilized for one patient with a large complex knee joint soft tissue defect, and segmental deficiency of the patellar tendon. The fascia lata sheet was rolled to mimic a patellar tendon. The exposed knee joint was obturated by the vastus lateralis muscle of the ALT myocutaneous flap. The skin and soft tissue defect was reconstructed using the skin paddle of the ALT flap. The patient's postoperative course was uneventful. An MRI examination demonstrated good continuity of the reconstructed patellar tendon. The active ROM of the injured knee reached 100 degrees (extension deficiency 20 degrees and flexion 120 degrees ) at 5 years. Objective functional assessment of the patella-femoral joint utilized a kinetic communicator machine (Kin-Com 500H, Chattecx, Chattanooga, TN, USA) revealed still mild extension insufficiency. However, the patient reported that he was able to perform normal daily activities without difficulty at 5-year follow-up. PMID:18215803

Kuo, Yur-Ren; An, Po-Chung; Kuo, Mei-Hui; Kueh, Nai-Siong; Yao, Sheng-Fa; Jeng, Seng-Feng

2008-01-01

255

Growth and maturational changes in dense fibrous connective tissue following 14 days of rhGH supplementation in the dwarf rat  

NASA Technical Reports Server (NTRS)

The purpose of this study was to investigate the impact of recombinant human growth hormone (rhGH) on patella tendon (PT), medial collateral ligament (MCL), and lateral collateral ligament (LCL) on collagen growth and maturational changes in dwarf GH-deficient rats. Twenty male Lewis mutant dwarf rats, 37 days of age, were randomly assigned to Dwarf + rhGH (n = 10) and Dwarf + vehicle (n = 10) groups. The GH group received 1.25 mg rhGH/kg body wt twice daily for 14 days. rhGH administration stimulated dense fibrous connective tissue growth, as demonstrated by significant increases in hydroxyproline specific activity and significant decreases in the non-reducible hydroxylysylpyridinoline (HP) collagen cross-link contents. The increase in the accumulation of newly accreted collagen was 114, 67, and 117% for PT, MCL, and LCL, respectively, in 72 h. These findings suggest that a short course rhGH treatment can affect the rate of new collagen production. However, the maturation of the tendon and ligament tissues decreased 18-25% during the rapid accumulation of de novo collagen. We conclude that acute rhGH administration in a dwarf rat can up-regulate new collagen accretion in dense fibrous connective tissues, while causing a reduction in collagen maturation. Copyright 2002 Elsevier Science Ltd.

Kyparos, Antonios; Orth, Michael W.; Vailas, Arthur C.; Martinez, Daniel A.

2002-01-01

256

Intrinsic risk factors for the development of anterior knee pain in an athletic population. A two-year prospective study.  

PubMed

Many variables have retrospectively been associated with the presence of anterior knee pain. Very few prospective data exist, however, to determine which of these variables will lead to the development of anterior knee pain. It was our purpose in this study to determine the intrinsic risk factors for the development of anterior knee pain in an athletic population over a 2-year period. Before the start of training, 282 male and female students enrolled in physical education classes were evaluated for anthropometric variables, motor performance, general joint laxity, lower leg alignment characteristics, muscle length and strength, static and dynamic patellofemoral characteristics, and psychological parameters. During this 2-year follow-up study, 24 of the 282 students developed patellofemoral pain. Statistical analyses revealed a significant difference between those subjects who developed patellofemoral pain and those who did not concerning quadriceps and gastrocnemius muscle flexibility, explosive strength, thumb-forearm mobility, reflex response time of the vastus medialis obliquus and vastus lateralis muscles, and the psychological parameter of seeking social support. However, only a shortened quadriceps muscle, an altered vastus medialis obliquus muscle reflex response time, a decreased explosive strength, and a hypermobile patella had a significant correlation with the incidence of patellofemoral pain. We concluded that the latter four parameters play a dominant role in the genesis of anterior knee pain and we therefore deem them to be risk factors for this syndrome. PMID:10921638

Witvrouw, E; Lysens, R; Bellemans, J; Cambier, D; Vanderstraeten, G

2000-01-01

257

Patellofemoral instability: classification and imaging  

PubMed Central

Patellofemoral disorders must be approached through an appropriate process of diagnostic framing, performed using language that is, as far as possible, unequivocal and a validated and organic classification system. At present, the classification proposed by the Lyonnaise school, which fulfills these requirements, is the most complete. This classification divides patellofemoral disorders into three groups: objective patellar instability, potential patellar instability and painful patella syndrome. It also identifies three principal factors of instability: trochlear dysplasia, abnormal patellar height and pathological tibial tubercle-trochlear groove (TT-TG) distance. Imaging is crucial for correct classification and for identifying and measuring the principal factors of instability. Up to now, the emphasis has been placed on the contribution made by traditional diagnostic radiology and computed tomography. In recent years, however, growing attention has been paid to the use of magnetic resonance imaging in the assessment of the patellofemoral joint and in the study of factors of instability, even though there is still a need for validation of this approach before it can be routinely used in preoperative planning.

BERRUTO, MASSIMO; FERRUA, PAOLO; CARIMATI, GIULIA; UBOLDI, FRANCESCO; GALA, LUCA

2013-01-01

258

Infective endocarditis complicated by aortic graft infection and osteomyelitis: case report and review of literature  

PubMed Central

Primary aortic graft infection early after aortic graft insertion is well described in the literature. Here, we present a unique case of late aortic graft infection 5 years after insertion secondary to mitral valve endocarditis, resulting from cellulitis in a patient with severe venous varicosities. A 63-year-old male presented for severe low back pain, constipation, and low-grade fever. An abdominal computed tomography scan with oral and intravenous contrast showed a normal spine and urinary tract. Blood and urine cultures, done at the same time, grew Staphylococcus aureus. A transesophageal echocardiogram confirmed the diagnosis of endocarditis. Subsequently, a gallium scan showed increased uptake in the vertebral bodies, aortic graft, left patella, and left ankle. After 3 months of antibiotic therapy, the patient’s low back pain resolved with normalization of his laboratory values. He remained free of infection at a 2-year follow-up. We reviewed the literature concerning the atypical presentation of infective endocarditis, with a focus on distant metastases at initial presentation, such as osteomyelitis and aortic graft infection, as well as the different treatment modalities. This report describes successful medical treatment with intravenous followed by oral antibiotics for an infected endovascular graft without any surgical intervention. PMID:22866008

Zouein, Elie; Wetz, Robert; Mobarakai, Neville; Hassan, Samer; Tong, Iris

2012-01-01

259

Breaking the Law of Valgus: the surprising and unexplained prevalence of medial patellofemoral cartilage damage  

PubMed Central

Objectives To compare the prevalence of medial and lateral patellofemoral (PF) cartilage damage in three large osteoarthritis (OA) studies and determine the relationship of this damage to varus, neutral, and valgus knee alignment. Methods In the Boston OA of the Knee (BOKS), Framingham OA (FOA), and Multicenter OA (MOST) studies, MRIs were read for cartilage morphology at the medial and lateral patella and trochlea femoris using Whole-Organ MRI Scores (WORMS). WORMS scores ? 2 (any cartilage defect), ? 3 (areas of partial thickness loss), ? 4 (diffuse partial thickness loss), and ? 5 (extensive full thickness loss) were all variously considered as thresholds to identify damage that may indicate OA. Full-limb radiographs were measured for mechanical alignment, and varus (< ?2°), neutral (?2° to 2°), and valgus (> 2°) knees were identified. Results The prevalence of medial PF cartilage damage exceeded that of lateral damage in all three OA studies and according to nearly every threshold. Only among severely involved knees (WORMS ? 4 or ? 5) did the prevalence of lateral PF cartilage damage approximate that of medial damage. The high prevalence of medial PF damage persisted in all strata of knee alignment. Even among knees with valgus malalignment, the prevalence of lateral PF cartilage damage equaled or surpassed that of medial PF damage only when the threshold was specific to severely involved knees. Conclusions Medial PF cartilage damage is at least as prevalent among older adults as lateral PF cartilage damage. PMID:22534825

Gross, K. Douglas; Niu, Jingbo; Stefanik, Joshua J.; Guermazi, Ali; Roemer, Frank W.; Sharma, Leena; Nevitt, Michael C.; Segal, Neil A.; Lewis, Cora E.; Felson, David T.

2013-01-01

260

An Isolated Medial Patellofemoral Ligament Reconstruction with Patellar Tendon Autograft  

PubMed Central

The aim of the study was to evaluate the results of the medial patellofemoral ligament reconstruction with a medial strip of patellar tendon autograft after a minimum 2-year followup. Ten patients (10 knees) were operated on by one surgeon, according to the modified technique, described by Camanho, without any bone plug at free graft end. The mean age of the patients was 27.2 years (ranging from 18 to 42 years). The mean follow-up period was 3 years and 7 months. All patients were reviewed prospectively. At the last follow-up visit, all the patients demonstrated a significant improvement in terms of patellofemoral joint stability, all aspects of the KOOS questionnaire, and Kujala et al.'s score (59.7 points preoperatively and 84.4 points at the last followup). No patient revealed recurrent dislocation. The SF-36 score revealed a significant improvement in bodily pain, general health, physical role functioning, social role functioning, and physical functioning domains. The described MPFL reconstruction with the use of the medial 1/3rd of patella tendon is an effective procedure that gives satisfactorily patellofemoral joint functions, improves the quality of life, and provides much pain relief. It is relatively simple, surgically not extensive, and economically cost-effective procedure. PMID:24224173

Wito?ski, Dariusz; K?ska, Rafa?; Synder, Marek; Sibi?ski, Marcin

2013-01-01

261

Hamstring tendon graft for anterior cruciate ligament reconstruction.  

PubMed

In an age of increasing emphasis on sports, the most common contact injury of the lower extremity is anterior cruciate ligament (ACL) rupture. The classic history of an ACL injury is a sudden twisting of the knee accompanied by a popping or snapping sound. The patient usually complains of a feeling of hesitation, instability, or giving way of the knee. By the end of the day, the patient's knee will be swollen and unstable. There are many ways that the ACL can rupture, but a common method is a contact injury in which a valgus force is applied to the flexed, rotated externally knee. This can produce tears to the ACL, medial collateral ligament, and menisci. Noncontact injuries, such as those incurred while skiing or jumping, occur when the knee is extended and the tibia is internally rotated on the femur. There are several methods of repairing a ruptured ACL, such as using an allograft or autograft of the patella tendon or a hamstring tendon graft for the repair. This article focuses on the use of a hamstring tendon graft for ACL reconstruction and how to care for patients undergoing this procedure. PMID:12382466

Boni, Deborah M; Herriott, George E

2002-10-01

262

Osteology and radiographic anatomy of the pelvis and hind limb of healthy ring-tailed lemurs (Lemur catta).  

PubMed

In family Lemuridae, anatomical variations exist. Considering its conservation status (near threatened) and presence of similarities between strepsirrhines and primitive animals, it was thought to be beneficial to describe the gross osteology and radiographic anatomy of the pelvis and hind limb of ring-tailed lemurs (Lemur catta) as a reference for clinical use and species identification. Radiography was performed in 14 captive adult ring-tailed lemurs. The radiographic findings were correlated with bone specimens from two adult animals. Additionally, computed tomography of the hind limbs was performed in one animal. The pelvic bone has a well-developed caudal ventral iliac spine. The patella has a prominent tuberosity on the cranial surface. The first metatarsal bone and digit 1 are markedly stouter than the other metatarsal bones and digits with medial divergence from the rest of the metatarsal bones and digits. Ossicles were seen in the lateral meniscus, inter-phalangeal joint of digit 1 and in the infrapatellar fat pad. Areas of mineral opacity were seen within the external genitalia, which are believed to be the os penis and os clitoris. Variations exist in the normal osteology and radiographic appearance of the pelvis and hind limb of different animal species. The use of only atlases from domestic cats and dogs for interpretative purposes may be misleading. PMID:23651234

Makungu, M; Groenewald, H B; du Plessis, W M; Barrows, M; Koeppel, K N

2014-06-01

263

Effect of Laser Acupuncture on Disuse Osteoarthritis: An Ultrasound Biomicroscopic Study of Patellar Articular Cartilage in Rats  

PubMed Central

To investigate the effect of laser acupuncture (LA) on disuse changes in articular cartilage using ultrasound biomicroscopy (UBM), Eighteen rats were randomly divided into the control group (C), the tail-suspended group (T), and the tail-suspended with LA treatment group (L). During 28-day suspension period, group L were treated with LA at acupoints on the left hindlimb while group T had a sham treatment. Ultrasound roughness index (URI), integrated reflection coefficient (IRC), integrated backscatter coefficient (IBC), cartilage thickness, and ultrasonographic score (US) of articular cartilage at patella were measured by using an ultrasound biomicroscopy system (UBS). Compared with the group C, URI significantly (P < 0.01) increased by 60.9% in group T, increased by 38.1% in group L. In addition, unloading induced a significant cartilage thinning (P < 0.05) in group T, whereas cartilage thickness in group L was 140.22 ± 19.61??m reaching the level of the control group (147.00 ± 23.99??m). There was no significant difference in IRC, IBC, and US among the three groups. LA therapy could help to retain the quality of articular cartilage which was subjected to unloading. LA would be a simple and safe nonpharmacological countermeasure for unloading-induced osteoarthritis. The UBM system has potential to be a sensitive, specific tool for quantitative assessment of articular cartilage. PMID:22888368

Wang, Qing; Guo, Xia; Liu, Mu-Qing; Wang, Xiao-Yun; Zheng, Yong-Ping

2012-01-01

264

Determination of trace metal baseline values in Posidonia oceanica, Cystoseira sp., and other marine environmental biomonitors: a quality control method for a study in South Tyrrhenian coastal areas.  

PubMed

In this study, we investigated Cd, Cr, Cu, Pb, and Zn in the seagrass Posidonia oceanica (L.) Delile leaves and in the brown algae Cystoseira sp. sampled along a 280-km transect in the Tyrrhenian Sea, from the Ustica to Linosa Islands (Sicily, Italy) with the aim to determine their control charts (baseline levels). By applying the Johnson's (Biometrika 36:149-175, 1949) probabilistic method, we determined the metal concentration overlap ranges in a group of five biomonitors. Here, we propose the use of the indexes of bioaccumulation with respect to the lowest (L'i) and the highest (L i) extreme values of the overlap metal concentration ranges. These indexes allow the identification of the most opportune organism (or a suite of them) to better managing particular environmental conditions. Posidonia leaves have generally high L i indexes for Cd, Cu, Pb, and Zn, and this suggests its use as biomonitor for baseline marine areas. Our results confirm the high aptitude of Patella as a good biomonitor for Cd levels in seawater. From this study, Ustica resulted with higher levels of Cd, Cu, Pb, and Zn than the other Sicilian Islands. PMID:25253055

Conti, Marcelo Enrique; Mecozzi, Mauro; Finoia, Maria Grazia

2014-09-26

265

Porous tantalum in reconstructive surgery of the knee: a review.  

PubMed

Porous tantalum represents an alternative metal for primary and revision total knee arthroplasty (TKA) with several unique properties. Tantalum is a transition metal, which in its bulk form has shown excellent biocompatibility and is safe to use in vivo as evidenced by its current application in pacemaker electrodes, cranioplasty plates, and as radiopaque markers. Current designs for orthopedic implants maintain a high volumetric porosity (70%-80%), low modulus of elasticity (3 MPa), and high frictional characteristics, making this metal conducive to biologic fixation. The low modulus of elasticity of such components allows for more physiologic load transfer and relative preservation of bone stock. Its more bioactive nature and ingrowth properties have led to its use in primary as well as revision knee components with good early clinical results reported. In revision arthroplasty, it has been used as a structural bone graft substitute. Formation of a bone-like apatite coating in vivo affords strong fibrous ingrowth properties and allows for substantial soft-tissue attachment with the potential for use in cases such as mega-prostheses and patella salvage. Although porous tantalum is in its early stages of evolution, the initial clinical data and basic science studies support its use as an alternative to traditional orthopedic implant materials. PMID:17665779

Levine, Brett; Sporer, Scott; Della Valle, Craig J; Jacobs, Joshua J; Paprosky, Wayne

2007-07-01

266

Effect of preconditioning on the viscoelastic response of primate patellar tendon.  

PubMed

Current techniques for anterior cruciate ligament reconstruction with patellar tendon (PT) allow a measurable tension to be applied to the graft at the time of fixation. The viscoelastic nature of the PT, however, ensures that relaxation will cause the graft tension to decrease over time. To better understand this process, a primate model was used to evaluate acute viscoelastic relaxation in the PT. Thirty-five patella-patellar tendon-tibia (P-PT-T) complexes were harvested from normal primate knees (Cynomolgus monkeys), and were divided into five groups for mechanical comparison. Specimens were subjected to two 10-min relaxation tests separated by a 1-30-min unloaded interval. The first test provided baseline relaxation data as well as serving as preconditioning for the second test. Results indicate that preconditioning significantly reduces the tension lost in a graft due to viscoelastic relaxation. The effect of preconditioning is reduced with increasing recovery time (the time between preconditioning and the second relaxation test), but the effect is still significant after 30 min of unloading. No differences were observed in the relaxation behavior of specimens that were cyclicly or isometrically preconditioned, nor were differences observed between irradiated and nonirradiated specimens. These results suggest that preconditioning can reduce acute tension loss in a graft due to viscoelastic relaxation and that simple isometric preconditioning is just as effective as cyclic stretching. PMID:8166908

Graf, B K; Vanderby, R; Ulm, M J; Rogalski, R P; Thielke, R J

1994-02-01

267

Incidence of patellar clunk syndrome in fixed versus high-flex mobile bearing posterior-stabilized total knee arthroplasty.  

PubMed

The geometry of the intercondylar box plays a significant role in the development of patellar clunk syndrome. We reviewed the incidence of patella clunk at mid-to-long-term follow-up of a rotating high-flex versus fixed bearing posterior stabilized TKA design. 188-mobile and 223-fixed bearing TKAs were reviewed for complications, incidence of patellar clunk, treatment, recurrence rates, range of motion, and patient satisfaction. Patellar clunk developed in 22 knees in the mobile (11.7%) and in 4 (1.8%) in the fixed bearing group (P<0.001). 23 out of 26 cases resolved with a single arthroscopic treatment and 2 resolved with a second procedure. The mean postoperative range of motion was 122.4°. All but one patient reported overall satisfaction with the index procedure. In contrast with other recent studies we found a significant incidence of patellar clunk in high-flex mobile bearings. Despite the high rate of patellar clunk syndrome, overall patients did well and were satisfied with their outcomes. PMID:24961894

Snir, Nimrod; Schwarzkopf, Ran; Diskin, Brian; Takemoto, Richelle; Hamula, Mathew; Meere, Patrick A

2014-10-01

268

An investigation into the architecture of the vastus medialis oblique muscle in athletic and sedentary individuals: An in vivo ultrasound study.  

PubMed

There is thought to be a relationship between the vastus medialis oblique muscle (VMO) and patellofemoral pain syndrome (PFPS), a condition that has a high prevalence in young athletic individuals. Following a suggestion that there may be a link between the architecture of the VMO and an individual's activity level, the aim of this study was to determine any differences in two measurable parameters of the VMO between two populations with widely differing activity levels. The parameters measured were VMO fiber angle and insertion ratio, which is the proportion of the medial patellar border with VMO fibers inserting onto it (%). Eighty-two knees from 26 athletic volunteers and 15 sedentary volunteers (aged 20-28 years) were assessed using ultrasound. Activity level was defined using the Tegner scoring system. The mean VMO angle (°) for the athletic group was significantly higher than for the sedentary group at 67.8° and 53.6°, respectively. There was no significant difference in insertion ratio between the athletic group, 43.0%, and the sedentary group, 39.5%. This study found that greater VMO fiber angles were seen in individuals with higher activity levels, exerting a stronger medial stabilizing force on the patella. This has important implications for the treatment of PFPS, particularly in athletic patients, which frequently focus on VMO strengthening exercises. Clin. Anat. 28:262-268, 2015. © 2014 Wiley Periodicals, Inc. PMID:25244030

Benjafield, A J; Killingback, A; Robertson, C J; Adds, P J

2015-03-01

269

Fractal analysis of bone structure with applications to osteoporosis and microgravity effects  

SciTech Connect

The authors characterize the trabecular structure with the aid of fractal dimension. The authors use Alternating Sequential filters to generate a nonlinear pyramid for fractal dimension computations. The authors do not make any assumptions of the statistical distributions of the underlying fractal bone structure. The only assumption of the scheme is the rudimentary definition of self similarity. This allows them the freedom of not being constrained by statistical estimation schemes. With mathematical simulations, the authors have shown that the ASF methods outperform other existing methods for fractal dimension estimation. They have shown that the fractal dimension remains the same when computed with both the X-Ray images and the MRI images of the patella. They have shown that the fractal dimension of osteoporotic subjects is lower than that of the normal subjects. In animal models, the authors have shown that the fractal dimension of osteoporotic rats was lower than that of the normal rats. In a 17 week bedrest study, they have shown that the subject`s prebedrest fractal dimension is higher than that of the postbedrest fractal dimension.

Acharya, R.S.; Swarnarkar, V.; Krishnamurthy, R.; Hausman, E. [State Univ. of New York, Buffalo, NY (United States). Biomedical Imaging Group; LeBlanc, A.; Lin, C. [Baylor Coll. of Medicine, Houston, TX (United States); Shackelford, L. [National Aeronautics and Space Administration, Houston, TX (United States). Johnson Space Center

1995-12-31

270

High elastic modulus nanoparticles: a novel tool for subfailure connective tissue matrix damage.  

PubMed

Subfailure matrix injuries such as sprains and strains account for a considerable portion of ligament and tendon pathologies. In addition to the lack of a robust biological healing response, these types of injuries are often characterized by seriously diminished matrix biomechanics. Recent work has shown nanosized particles, such as nanocarbons and nanocellulose, to be effective in modulating cell and biological matrix responses for biomedical applications. In this article, we investigate the feasibility and effect of using high stiffness nanostructures of varying size and shape as nanofillers to mechanically reinforce damaged soft tissue matrices. To this end, nanoparticles (NPs) were characterized using atomic force microscopy and dynamic light scattering techniques. Next, we used a uniaxial tensile injury model to test connective tissue (porcine skin and tendon) biomechanical response to NP injections. After injection into damaged skin and tendon specimens, the NPs, more notably nanocarbons in skin, led to an increase in elastic moduli and yield strength. Furthermore, rat primary patella tendon fibroblast cell activity evaluated using the metabolic water soluble tetrazolium salt assay showed no cytotoxicity of the NPs studied, instead after 21 days nanocellulose-treated tenocytes exhibited significantly higher cell activity when compared with nontreated control tenocytes. Dispersion of nanocarbons injected by solution into tendon tissue was investigated through histologic studies, revealing effective dispersion and infiltration in the treated region. Such results suggest that these high modulus NPs could be used as a tool for damaged connective tissue repair. PMID:24924347

Empson, Yvonne M; Ekwueme, Emmanuel C; Hong, Jung K; Paynter, Danielle M; Kwansa, Albert L; Brown, Chalmers; Pekkanen, Allison M; Roman, Maren; Rylander, Nichole M; Brolinson, Gunnar P; Freeman, Joseph W

2014-09-01

271

Autologous hamstring tendon used for revision of quadiceps tendon tears.  

PubMed

A paucity of literature exists on quadriceps tendon reruptures. Failed quadriceps tendon repair can cause significant morbidity and disability. Surgical management of quadriceps tendon rerupture can be challenging due to tissue degeneration, tendon retraction, muscle atrophy, and poor bone fixation. A lack of guidance in the literature exists on the appropriate surgical techniques for managing quadriceps tendon reruptures.This article describes the case of a male recreational athlete with a failed primary quadriceps tendon repair who presented 10 months after rerupture. Examination was significant for morbid obesity, assisted ambulation, and a significant defect at the superior pole of the patella on the affected side. Intraoperative findings were consistent with a 2.0- to 4.5-cm tendon defect across the extensor mechanism with complete retinaculi tears. The authors performed a novel surgical approach for revision of quadriceps tears using a bilateral hamstring autograft through a quadriceps tendon weave and a transosseous patellar repair. Tendon length was restored, and extensor mechanism tension was reapproximated. Postoperatively, the patient achieved a good outcome and had returned to full, painless, sport participation at 2-year follow-up.This surgical technique is suitable for revision quadriceps tendon repairs of large tendon gap defects, repairs desiring tendon-to-bone in-growth, and repairs requiring large-force transmission across the repair. PMID:23590798

McCormick, Frank; Nwachukwu, Benedict U; Kim, Jaehon; Martin, Scott D

2013-04-01

272

Assessment of Lower Limb Prosthesis through Wearable Sensors and Thermography  

PubMed Central

This study aimed to explore the application of infrared thermography in combination with ambulatory wearable monitoring of temperature and relative humidity, to assess the residual limb-to-liner interface in lower-limb prosthesis users. Five male traumatic transtibial amputees were involved, who reported no problems or discomfort while wearing the prosthesis. A thermal imaging camera was used to measure superficial thermal distribution maps of the stump. A wearable system for recording the temperature and relative humidity in up to four anatomical points was developed, tested in vitro and integrated with the measurement set. The parallel application of an infrared camera and wearable sensors provided complementary information. Four main Regions of Interest were identified on the stump (inferior patella, lateral/medial epicondyles, tibial tuberosity), with good inter-subject repeatability. An average increase of 20% in hot areas (P < 0.05) is shown after walking compared to resting conditions. The sensors inside the cuff did not provoke any discomfort during recordings and provide an inside of the thermal exchanges while walking and recording the temperature increase (a regime value is ?+1.1 ± 0.7 °C) and a more significant one (?+4.1 ± 2.3%) in humidity because of the sweat produced. This study has also begun the development of a reference data set for optimal socket/liner-stump construction. PMID:24618782

Cutti, Andrea Giovanni; Perego, Paolo; Fusca, Marcello C.; Sacchetti, Rinaldo; Andreoni, Giuseppe

2014-01-01

273

COL5A1: Fine genetic mapping, intron/exon organization, and exclusion as candidate gene in families with tuberous sclerosis complex 1, hereditary hemorrhagic telangiectasia, and Ehlers-Danlos syndrome type II  

SciTech Connect

Type V collagen is the only fibrillar collagen which has yet to be implicated in the pathogenesis of genetic diseases in humans or mice. To begin examining the possible role of type V collagen in genetic disease, we have previously mapped COL5A1, the gene for the {alpha}1 chain of type V collagen, to 9q23.2{r_arrow}q34.3 and described two restriction site polymorphisms which allowed us to exclude COL5A1 as candidate gene for nail-patella syndrome. We have now used these polymorphisms to exclude COL5A1 as candidate gene for tuberous sclerosis complex 1 and Ehlers-Danlos syndrome type II. In addition, we describe a CA repeat, with observed heterozygosity of about 0.5, in a COL5A1 intron, which has allowed us to exclude COL5A1 as a candidate gene in hereditary hemorrhagic telangiectasia and to place COL5A1 on the CEPH family genetic map between markers D9S66 and D9S67. We have also determined the entire intron/exon organization of COL5A1, which will facilitate characterization of mutations in genetic diseases with which COL5A1 may be linked in future studies.

Greenspan, D.S. [Univ. of Wisconsin, Madison, WI (United States); Papenberg, K.A.; Marchuk, D.A. [Duke Univ., Durham, NC (United States)] [and others

1994-09-01

274

The contribution of the medial retinaculum and quadriceps muscles to patellar lateral stability--an in-vitro study.  

PubMed

Patellofemoral joint stability is a result of the restraining effects of the quadriceps muscles, the retinacular structures, and engagement of the bones. The role and significance of these mechanisms in restraining patellar lateral displacement was investigated in this study by measuring the force needed to cause 5 mm lateral displacement (i.e. the mechanical stability, or 'stabilising force') of the patella. Six cadaver knees had 175 N quadriceps load distributed among three muscle groups. With a force ratio matching the muscles physiological cross sectional areas, no significant change occurred in the patellar stabilising force between 0 and 60 degrees knee flexion, but a significant increase occurred between 60 and 90 degrees, presumably reflecting the contribution of the femoral groove. Variation of the quadriceps force distribution changed the stability significantly. Relaxing the vastus lateralis increased the patellar lateral stabilising force 52+/-8%, while relaxing vastus medialis reduced the stabilising force 47+/-9%. The minimum stabilising force was at 30 degrees knee flexion. Transection of the medial retinaculum reduced the lateral stabilising force 34% in the extended knee. This effect disappeared by 45 degrees knee flexion. It was concluded that the quadriceps muscles had a significant and consistent effect across the whole range of knee flexion, but the contribution of the medial retinaculum was restricted to extended knee postures. PMID:15066616

Farahmand, Farzam; Naghi Tahmasbi, Mohammad; Amis, Andrew

2004-04-01

275

Extensile medial approach to the femur.  

PubMed

A proposed extensile medial approach to the medial surface of the shaft of the femur was studied on 30 cadaver thighs. The incision is made along a line extending from the mid inguinal point to a point one-third the distance from the adductor tubercle to the medial side of the patella. After mobilizing the sartorius muscle posteromedially, the medial femur is exposed by a three-step technique. Step I involves bluntly defining the internervous plane distally between the vastus medialis muscle and the adductor magnus tendon until limited proximally by the distal end of the vastoadductor membrane at an average of 9 cm from the adductor tubercle. In step II blunt dissection between the vastus medialis and the adductor longus muscles is carried from proximal to distal until limited by the proximal end of the vastoadductor membrane. Now the well-defined vastoadductor membrane area ("danger zone") measuring 6 cm in length on average is safely dealt with (step III) and the medial femur is exposed. Distal extension can be made to expose the knee joint. The approach can be extended proximally to the lesser trochanter between the vastus medialis and both the adductor brevis and pectineus muscles. Anatomic measurements in relation to the adductor tubercle and cross-sections of the thigh were made to better describe anatomic constants and variables in this rather unfamiliar medial thigh area. PMID:8892148

Checroun, A J; Mekhail, A O; Ebraheim, N A; Jackson, W T; Yeasting, R A

1996-01-01

276

Arthritogenic alphaviral infection perturbs osteoblast function and triggers pathologic bone loss  

PubMed Central

Arthritogenic alphaviruses including Ross River virus (RRV), Sindbis virus, and chikungunya virus cause worldwide outbreaks of musculoskeletal disease. The ability of alphaviruses to induce bone pathologies remains poorly defined. Here we show that primary human osteoblasts (hOBs) can be productively infected by RRV. RRV-infected hOBs produced high levels of inflammatory cytokine including IL-6. The RANKL/OPG ratio was disrupted in the synovial fluid of RRV patients, and this was accompanied by an increase in serum Tartrate-resistant acid phosphatase 5b (TRAP5b) levels. Infection of bone cells with RRV was validated using an established RRV murine model. In wild-type mice, infectious virus was detected in the femur, tibia, patella, and foot, together with reduced bone volume in the tibial epiphysis and vertebrae detected by microcomputed tomographic (µCT) analysis. The RANKL/OPG ratio was also disrupted in mice infected with RRV; both this effect and the bone loss were blocked by treatment with an IL-6 neutralizing antibody. Collectively, these findings provide previously unidentified evidence that alphavirus infection induces bone loss and that OBs are capable of producing proinflammatory mediators during alphavirus-induced arthralgia. The perturbed RANKL/OPG ratio in RRV-infected OBs may therefore contribute to bone loss in alphavirus infection. PMID:24733914

Chen, Weiqiang; Foo, Suan-Sin; Rulli, Nestor E.; Taylor, Adam; Sheng, Kuo-Ching; Herrero, Lara J.; Herring, Belinda L.; Lidbury, Brett A.; Li, Rachel W.; Walsh, Nicole C.; Sims, Natalie A.; Smith, Paul N.; Mahalingam, Suresh

2014-01-01

277

Denham total knee arthroplasty: a 10-year follow-up study.  

PubMed

We reviewed 72 patients with 89 Denham total knee arthroplasties (Biomet, Warsaw, IN) (TKAs) 10 to 15 years after the operation. Of 8 TKAs that were considered as failures, 5 had been revised at the time of review for pain and aseptic loosening, and 3 others were considered to have failed because of breakage of the polyethylene tibial plateau, dislocation, and infection. Survival analysis suggested a 10-year survival rate of 92.7%. There were 36 patients with 45 TKAs alive at the time of follow-up. We reviewed 32 of the patients with 40 Denham TKAs that had not failed. Their average age was 81 years (range, 58-93 years). They were reviewed at an average of 11.8 years after TKA. Nine knees (6 patients) had some anterior knee pain from the unresurfaced patella. Restriction of function was mainly due to medical conditions and old age. Survival analysis performed with the living patients found the 10-year survival to be 91.1%. Long-term survival shows that the Denham knee prosthesis is effective despite its simplicity. PMID:12168168

Mangaleshkar, Singu R; Bajaj, Sunil K; Thomas, Andrew P

2002-08-01

278

Automated planning of MRI scans of knee joints  

NASA Astrophysics Data System (ADS)

A novel and robust method for automatic scan planning of MRI examinations of knee joints is presented. Clinical knee examinations require acquisition of a 'scout' image, in which the operator manually specifies the scan volume orientations (off-centres, angulations, field-of-view) for the subsequent diagnostic scans. This planning task is time-consuming and requires skilled operators. The proposed automated planning system determines orientations for the diagnostic scan by using a set of anatomical landmarks derived by adapting active shape models of the femur, patella and tibia to the acquired scout images. The expert knowledge required to position scan geometries is learned from previous manually planned scans, allowing individual preferences to be taken into account. The system is able to automatically discriminate between left and right knees. This allows to use and merge training data from both left and right knees, and to automatically transform all learned scan geometries to the side for which a plan is required, providing a convenient integration of the automated scan planning system in the clinical routine. Assessment of the method on the basis of 88 images from 31 different individuals, exhibiting strong anatomical and positional variability demonstrates success, robustness and efficiency of all parts of the proposed approach, which thus has the potential to significantly improve the clinical workflow.

Bystrov, Daniel; Pekar, Vladimir; Young, Stewart; Dries, Sebastian P. M.; Heese, Harald S.; van Muiswinkel, Arianne M.

2007-03-01

279

Medial patellofemoral ligament reconstruction in patellar instability  

PubMed Central

Background: Medial patellofemoral ligament (MPFL) is one of the major static medial stabilising structures of the patella. MPFL is most often damaged in patients with patellar instability. Reconstruction of MPFL is becoming a common surgical procedure in treating patellar instability. We hypothesised that MPFL reconstruction was adequate to treat patients with patellar instability if the tibial tubercle and the centre of the trochlear groove (TT-TG) value was less than 20 mm and without a dysplastic trochlea. Materials and Methods: 30 patients matching our inclusion criteria and operated between April 2009 and May 2011 were included in the study. MPFL reconstruction was performed using gracilis tendon fixed with endobutton on the patellar side and bio absorbable interference screw or staple on the femoral side. Patients were followed up with subjective criteria, Kujala score and Lysholm score. Results: The mean duration of followup was 25 months (range 14-38 months). The mean preoperative Kujala score was 47.5 and Lysholm score was 44.7. The mean postoperative Kujala score was 87 and Lysholm score was 88.06. None of the patients had redislocation. Conclusion: MPFL reconstruction using gracilis tendon gives excellent results in patients with patellar instability with no redislocations. Some patients may have persistence of apprehension. PMID:25298558

Krishna Kumar, MS; Renganathan, Sankarram; Joseph, Clement J; Easwar, TR; Rajan, David V

2014-01-01

280

Autologous osteochondral transplantation using the diamond bone-cutting system (DBCS): 6-12 years' follow-up of 35 patients with osteochondral defects at the knee joint.  

PubMed

Thirty-five patients with severe osteochondral defects were treated by autologous osteochondral transplantation between 1986 and 1992. The majority of patients (27) suffered from osteochondrosis dissecans, while 8 patients presented with posttraumatic osteochondral defects. The grafts were harvested with a diamond bone cutter from the posterior part of the medial or lateral femoral condyle. In 29 patients the lesion was located at the lateral part of the medial femoral condyle, in 3 it was at the lateral femoral condyle, and in 3 at the patella. Twenty-nine patients could be examined at the follow-up between 6 and 12 years later (mean follow up 8.1 years). Using the standard cartilage evaluation form, the transplanted knees of 12 patients were graded as normal (grade I), 14 knees were nearly normal (grade II), while 3 patients presented with an abnormal result (grade III). All 3 of them had a varus malalignment and refused a high tibial correction osteotomy against our advice. No patient was assessed as severely abnormal (grade IV). The majority of patients improved their activity level and the functional status of the joint. Twelve patients developed new radiological signs of osteoarthrosis with a decrease in the radiological score of Kellgren and Lawrence by about one stage. We conclude that autologous osteochondral transplantation with the diamond bone-cutting system is an effective method in the treatment of severe osteochondral defects. PMID:11409552

Laprell, H; Petersen, W

2001-05-01

281

Characterization of microgravity effects on bone structure and strength using fractal analysis  

NASA Technical Reports Server (NTRS)

The effect of micro-gravity on the musculoskeletal system has been well studied. Significant changes in bone and muscle have been shown after long term space flight. Similar changes have been demonstrated due to bed rest. Bone demineralization is particularly profound in weight bearing bones. Much of the current techniques to monitor bone condition use bone mass measurements. However, bone mass measurements are not reliable to distinguish Osteoporotic and Normal subjects. It has been shown that the overlap between normals and osteoporosis is found for all of the bone mass measurement technologies: single and dual photon absorptiometry, quantitative computed tomography and direct measurement of bone area/volume on biopsy as well as radiogrammetry. A similar discordance is noted in the fact that it has not been regularly possible to find the expected correlation between severity of osteoporosis and degree of bone loss. Structural parameters such as trabecular connectivity have been proposed as features for assessing bone conditions. In this report, we use fractal analysis to characterize bone structure. We show that the fractal dimension computed with MRI images and X-Ray images of the patella are the same. Preliminary experimental results show that the fractal dimension computed from MRI images of vertebrae of human subjects before bedrest is higher than during bedrest.

Acharya, Raj S.; Shackelford, Linda

1995-01-01

282

Traversing the intact/fibrillated joint surface: a biomechanical interpretation  

PubMed Central

Cartilage taken from the osteoarthritic bovine patellae was used to investigate the progression of change in the collagenous architecture associated with the development of fibrillated lesions. Differential interference contrast optical microscopy using fully hydrated radial sections revealed a continuity in the alteration of the fibrillar architecture in the general matrix consistent with the progressive destructuring of a native radial arrangement of fibrils repeatedly interconnected in the transverse direction via a non-entwinement-based linking mechanism. This destructuring is shown to occur in the still intact regions adjacent to the disrupted lesion thus rendering them more vulnerable to radial rupture. Two contrasting modes of surface rupture were observed and these are explained in terms of the absence or presence of a skewed structural weakening of the intermediate zone. A mechanism of surface rupture initiation based on simple bi-layer theory is proposed to account for the intensification of surface ruptures observed in the intact regions on advancing towards the fibrillation front. Focusing specifically on the primary collagen architecture in the cartilage matrix, this study proposes a pathway of change from intact to overt disruption within a unified structural framework. PMID:15679871

Broom, Neil D; Ngo, Thuy; Tham, Evelyn

2005-01-01

283

Patellar tendinopathy in athletes. Outcome of nonoperative and operative management.  

PubMed

We report the results of nonoperative and operative management of patellar tendinopathy in 42 athletes with Blazina stage 2 (26 patients) or stage 3 (16 patients) patellar tendinopathy. All patients were initially managed nonoperatively with nonsteroidal antiinflammatory drugs, physical therapy, and a progressive rehabilitation program based on isometric exercises, stretching, and eccentric exercises. After 6 months, 33 patients showed symptomatic improvement and were able to resume their sports. In nine patients with Blazina stage 3 tendinopathy, nonoperative measures failed, and surgery was performed. Operative treatment consisted of removal of the degenerated areas of the tendon, multiple longitudinal tenotomies, and drilling of the lower pole of the patella at the site of tendon attachment. Histologic examination of the excised tendon tissue showed areas of necrosis and mucoid degeneration, and alterations of the bone-tendon junction. After a mean follow-up of 4.8 years, clinical results were excellent or good in all patients. In the group treated nonoperatively, results were better in the patients who had stage 2 tendinopathy than in those with stage 3. PMID:10843134

Panni, A S; Tartarone, M; Maffulli, N

2000-01-01

284

[Basic principles of aggressive rehabilitation after anterior cruciate ligament reconstruction].  

PubMed

Rehabilitation after ACL (anterior cruciate ligament) reconstruction has drastically changed over the last decade, with the adoption of a more aggressive approach, right from the first day after surgery. Progress in the effectiveness of rehabilitation is based on improvements in operative techniques, as well as on the encouraging results of histological studies regarding graft healing. Despite a huge amount of research papers on this topic, a rehabilitation golden standard still has not been established, due to the complexity of this problem. In this review, we point out the basic principles of rehabilitation after arthroscopically assisted ACL reconstruction based on actual practices, as well as the importance of specific procedures for the prevention of complications during the postoperative period. The importance of range-of-motion exercises, early weight bearing, an appropriate gait scheme, patella mobilisation, pain and oedema control, as well as stretching and balance exercises is explained. The functional advantages of closed kinetic chain exercises, as well as their influence on the graft are also described, in comparison to open kinetic chain exercises. The fundamentals of returning to sports are revealed and the specific aspects of rehabilitation regarding graft choice are pointed out. While waiting for new clinical investigations, which are expected to enable the establishment of a rehabilitation golden standard, the outlined principles should be followed. The complexity of this injury requires treatment in highly specialised institutions. PMID:16758856

Dubljanin-Raspopovi?, Emilija; Kadija, Marko; Matanovi?, Dragana

2005-01-01

285

The results of an extensive soft-tissue procedure in the treatment of obligatory patellar dislocation in children with ligamentous laxity: a post-operative isokinetic study.  

PubMed

In 11 paediatric patients (seven girls and four boys, from 12 to 15 years old) with unilateral obligatory patellar dislocation and ligamentous laxity vastus medialis advancement, lateral release, partial patellar ligament transposition and Galeazzi semitendinosus tenodesis was undertaken to stabilise the patella. The diagnostic criterion for ligamentous laxity was based on the Beighton scale. Outcomes were evaluated radiologically and functionally by measurement of the range of knee movement and isokinetic testing. The evaluation also included the Lysholm knee scale. Follow-up studies took place at a mean of 8.1 years (5 to 15) post-operatively. Normal patellar tracking without any recurrence of dislocation was obtained in ten out of 11 patients. Pain related to vigorous activity was reported by nine patients. Compared with the opposite normal side, the isokinetic tests revealed a statistically significant decrease in the maximal torque values for the affected quadriceps muscle (p = 0.003 and p = 0.004), but no difference between the knee flexors (for angular velocities of 60°/s and 180°/s) (p = 0.858 and p = 0.79). The applied surgical technique generally prevents the recurrence of the disorder in children with habitual patellar dislocation and ligamentous laxity. Quadriceps muscle weakness can be expected to occur post-operatively, Cite this article: Bone Joint J 2015;96-B:129-33. PMID:25568426

Niedzielski, K R; Malecki, K; Flont, P; Fabis, J

2015-01-01

286

Periprosthetic fractures around total knee arthroplasty  

PubMed Central

INTRODUCTION The number of total knee arthroplasties performed continues to rise annually and it would be expected that complications, which include periprosthetic fractures, will also therefore become more commonplace. This article reviews the current literature regarding this injury and identifies the treatment principles that enable patients to regain optimal function. METHODS A comprehensive search of the Pubmed and Embase™ databases was performed to identify relevant articles. Keywords and MeSH (Medical Subject Headings) terms included in the search strategy were ‘periprosthetic fracture(s)’, ‘femur’, ‘tibia’, ‘patella(r)’, ‘complication(s)’, ‘failure(s)’, ‘risk(s)’, ‘prevalence’, ‘incidence’, ‘epidemiology’ and ‘classification(s)’. The search was limited to all articles published in English and reference lists from the original articles were reviewed to identify pertinent articles to include in this review. A total number of 43 studies were identified. RESULTS Common treatment aims have been identified when managing patients with a periprosthetic fracture around total knee arthoplasty. The main criterion that determines which option to choose is the degree of remaining bone stock and the amount of fracture displacement. CONCLUSIONS Treatment of a periprosthetic fracture around total knee arthroplasty will either be non-operative, osteosynthesis or revision arthroplasty. It is imperative that a suitable option is chosen and based on the published literature, pathways are outlined to aid the surgeon. PMID:22943223

Sarmah, SS; Patel, S; Reading, G; El-Husseiny, M; Douglas, S; Haddad, FS

2012-01-01

287

Anterior Cruciate Ligament Reconstruction in Patients with Generalized Joint Laxity  

PubMed Central

Generalized joint laxity is a genetically determined component of overall joint flexibility. The incidence of joint laxity in the overall population is approximately 5% to 20%, and its prevalence is higher in females. Recently it was noticed that individuals with generalized joint laxity are not only prone to anterior cruciate ligament injuries but also have inferior results after a reconstruction. Therefore, an anterior cruciate ligament reconstruction in patients with generalized laxity should be undertaken with caution due to the higher expected failure rate from the complexity of problems associated with this condition. It is also necessary to identify the risk factors for the injury as well as for the post operative outcome in this population. A criterion that includes all the associated components is necessary for the proper screening of individuals for generalized joint laxity. Graft selection for an anterior cruciate reconstruction in patients with ligament laxity is a challenge. According to the senior author, a hamstring autograft is an inferior choice and a double bundle reconstruction with a quadriceps tendon-bone autograft yields better results than a single bundle bone-patella tendon-bone autograft. Future studies comparing the different grafts available might be needed to determine the preferred graft for this subset of patients. Improved results after an anterior cruciate ligament reconstruction can be achieved by proper planning and careful attention to each step beginning from the clinical examination to the postoperative rehabilitation. PMID:20808583

Kim, Sung-Jae; Kumar, Praveen

2010-01-01

288

[Knee endoprosthesis: aspects of surgical techniques].  

PubMed

The implantation of a condylar knee has remained a challenge for surgeons and the equipment of the hospital. In contrast to total hip arthroplasty, not only is the correct insertion of the implant crucial, but also the treatment of the surrounding soft tissues. Mediolateral soft tissue balance and balance between flexion and extension gaps, as well as centering the patella, have to be done carefully. The soft tissue envelope of the knee joint is thin and prone to necrosis after multiple incisions. Damage to the extension mechanism can make a total joint useless. Tearing the patellar ligament from the tibial tuberosity must therefore be avoided by all means during operation. Precise cutting of the distal femur is only possible if excellent equipment is used by a skillful surgeon. The same is true for orientating saw cuts related to the long leg axes. These tasks can probably be taken over by navigation systems and robots in the future. Because the definite choice of implants has to be made intraoperatively, a complete modular system has to be present in the hospital. Only hospitals that can properly equip their surgeons to manage upcoming soft tissue problems and bony deficiencies should offer treatment to patients requiring condylar knee arthroplasty. PMID:11013912

Kohn, D; Rupp, S

2000-08-01

289

Left-right asymmetric expression of dpp in the mantle of gastropods correlates with asymmetric shell coiling  

PubMed Central

Background Various shapes of gastropod shells have evolved ever since the Cambrian. Although theoretical analyses of morphogenesis exist, the molecular basis of shell development remains unclear. We compared expression patterns of the decapentaplegic (dpp) gene in the shell gland and mantle tissues at various developmental stages between coiled-shell and non-coiled-shell gastropods. Results We analyzed the expression patterns of dpp for the two limpets Patella vulgata and Nipponacmea fuscoviridis, and for the dextral wild-type and sinistral mutant lineage of the pond snail Lymnaea stagnalis. The limpets had symmetric expression patterns of dpp throughout ontogeny, whereas in the pond snail, the results indicated asymmetric and mirror image patterns between the dextral and sinistral lineages. Conclusion We hypothesize that Dpp induces mantle expansion, and the presence of a left/right asymmetric gradient of the Dpp protein causes the formation of a coiled shell. Our results provide a molecular explanation for shell, coiling including new insights into expression patterns in post-embryonic development, which should aid in understanding how various shell shapes are formed and have evolved in the gastropods. PMID:23711320

2013-01-01

290

Imaging characteristics of contralateral asymptomatic patellofemoral joints in patients with unilateral instability.  

PubMed

Purpose To test the hypothesis that in patients with unilateral patellofemoral instability ( PI patellofemoral instability ), the contralateral asymptomatic joints have abnormal morphology and imaging features of osteoarthritis ( OA osteoarthritis ) at four-dimensional ( 4D four-dimensional ) computed tomography (CT). Materials and Methods The institutional review board approved this HIPAA-compliant retrospective study. Informed consent was waived. Radiology records were reviewed to identify 25 patients (male-female ratio, 0.56; median age, 20 years; range, 13-43 years) with unilateral PI patellofemoral instability undergoing 4D four-dimensional CT and 25 age- and sex-matched control patients undergoing multidetector CT. Trochlear groove depth ( TGD trochlear groove depth ), tibial tuberosity-trochlear groove ( TT-TG tibial tuberosity-trochlear groove ) distance, and patellar height ratio ( PHR patellar height ratio ) were determined to compare morphology, and bisect offset ( BO bisect offset ) measurements were obtained to compare lateral displacement of the patella between the two groups by using the Wilcoxon rank-sum test. All images were interpreted by trained observers. Tracking patterns of the patellae were determined by obtaining BO bisect offset measurements at various flexion angles with 4D four-dimensional CT. Results In the contralateral asymptomatic joints, TGD trochlear groove depth (median, 3.0 mm; 95% confidence interval [ CI confidence interval ]: 2.5, 4.6; P < .0001), TT-TG tibial tuberosity-trochlear groove (median, 15 mm; 95% CI confidence interval : 12.7, 18; P = .008), PHR patellar height ratio (median, 1.17; 95% CI confidence interval : 1.09, 1.2; P = .002), and patellar lateral displacement ( BO bisect offset , 85%; 95% CI confidence interval : 76.2%, 98.2%; P < .0001) were different from measurements obtained in the control group: TGD trochlear groove depth median, 5.0 mm (95% CI confidence interval : 2.2, 7.6); TT-TG tibial tuberosity-trochlear groove median, 10.9 mm (95% CI confidence interval : 3.4, 20.7); PHR patellar height ratio median, 0.92 (95% CI confidence interval : 0.67, 1.36); and BO bisect offset median, 63% (95% CI confidence interval : 59%, 68.4%). OA osteoarthritis was detected in 40% of asymmetrical contralateral joints (10 of 25). By using 4D four-dimensional CT data, multiple regression analysis demonstrated that TGD trochlear groove depth (P = .026) and BO bisect offset measurements obtained at 30° of knee flexion (P = .047) had an association with the presence of OA osteoarthritis . Conclusion Abnormal morphology and imaging features of OA osteoarthritis are relatively common in contralateral asymptomatic joints of young patients with unilateral PI patellofemoral instability . © RSNA, 2014 Online supplemental material is available for this article. PMID:25153158

Demehri, Shadpour; Thawait, Gaurav K; Williams, Ariel A; Kompel, Andrew; Elias, John J; Carrino, John A; Cosgarea, Andrew J

2014-12-01

291

Spatial analysis of magnetic resonance T1? and T2 relaxation times improves classification between subjects with and without osteoarthritis  

PubMed Central

Purpose: Studies have shown that functional analysis of knee cartilage based on magnetic resonance (MR) relaxation times is a valuable tool in the understanding of osteoarthritis (OA). In this work, the regional spatial distribution of knee cartilage T1? and T2 relaxation times based on texture and laminar analyses was studied to investigate if they provide additional insight compared to global mean values in the study of OA. Methods: Knee cartilage of 36 subjects, 19 healthy controls and 17 with mild OA, was divided into 16 compartments. T1? and T2 relaxation times were studied with first order statistics, eight texture parameters with four different orientations using gray-level co-occurrence matrices and by subdividing each compartment into two different layers: Deep and superficial. Receiver operating characteristic curve analysis was performed to evaluate the potential of each technique to correctly classify the populations. Results: Although the deep and superficial cartilage layers had in general significantly different T1? and T2 relaxation times, they performed similarly in terms of subject discrimination. The subdivision of lateral and medial femoral compartments into weight-bearing and non-weight-bearing regions did not improve discrimination. Also it was found that the most sensitive region was the patella and that T1? discriminated better than T2. The most important finding was that with respect to global mean values, laminar and texture analyses improved subject discrimination. Conclusions: Results of this study suggest that spatially assessing MR images of the knee cartilage relaxation times using laminar and texture analyses could lead to better and probably earlier identification of cartilage matrix abnormalities in subjects with OA. PMID:19810478

Carballido-Gamio, Julio; Stahl, Robert; Blumenkrantz, Gabrielle; Romero, Adan; Majumdar, Sharmila; Link, Thomas M.

2009-01-01

292

Association of Trochlear Dysplasia with degenerative Abnormalities in the Knee  

PubMed Central

Objective To evaluate trochlear morphology as a potential risk factor for patellofemoral osteoarthritis, determined by morphological and quantitative measurements of cartilage degeneration using 3T magnetic resonance imaging (MRI) of the knee. Materials and Methods MR images of right knees of 304 randomly selected subjects, aged 45–60 years, from the Osteoarthritis Initiative (OAI) progression cohort were screened for trochlear dysplasia, defined by an abnormal trochlear depth. Out of 304 subjects, n=85 demonstrated a shallow trochlea (depth ?3mm; 28%). In these, and also in a random sample of controls with normal trochlear depth (n=50), the facetal ratio and the sulcus angle were calculated and knee structural abnormalities were assessed by using a modified Whole-Organ-MR-Imaging Score (WORMS). Cartilage segmentation was performed and T2 relaxation times and patellar cartilage volume were determined. ANOVA and multivariate regression models were used for statistical analysis of the association of MRI structural measures and trochlear morphology. Results Knees with a shallow trochlea showed higher patellofemoral degeneration (WORMS mean ±standard deviation, 11.2±0.5 versus 5.7±0.6; Multivariate regression, P<0.001) and lower patellar cartilage volume than controls (900±664mm3 versus 1671±671mm3; P<0.001). Knees with an abnormal medial-to-lateral facetal ratio (<0.4) showed increased patellofemoral WORMS scores (12.3±0.9 versus 8.3±0.5; P<0.001). Knees with an abnormal sulcus angle (>170°) also showed increased WORMS scores (12.2±1.1 versus 8.6±0.6; P=0.003). T2 values at the patella were significantly lower in the dysplasia group with a shallow trochlea. However, significance was lost after adjustment for cartilage volume (P=0.673). Conclusion Trochlear dysplasia, defined by a shallow trochlea, was associated with higher WORMS scores and lower cartilage volume, indicating more advanced osteoarthritis at the patellofemoral joint. PMID:23801099

Jungmann, Pia. M.; Tham, Seng-Choe; Liebl, Hans; Nevitt, Michael C; McCulloch, Charles E.; Lynch, John; Link, Thomas M.

2013-01-01

293

Long-term outcome of low contact stress total knee arthroplasty with different mobile bearing designs  

PubMed Central

Purpose to evaluate the differences in clinical outcome and survivorship of three different mobile bearings for total knee arthroplasty. Methods a retrospective study was conducted in 60 patients (53 females, 7 males, mean age: 68 years and 5 months) each submitted to total knee replacement using one of the three different mobile bearings of the LCS system (Depuy Johnson & Johnson, Warsaw, IN). The diagnosis was knee osteoarthritis in 57 cases and rheumatoid arthritis in three cases. Three different groups of 20 cases each were identified: total knee arthroplasties with mobile menisci (group 1); total knee arthroplasties with the rotating platform (group 2); and total knee arthroplasties with the anteroposterior glide platform (group 3). As regards the component fixation, 33 implants were cementless, three were cemented, and in 24 only the tibial component was cemented. The patella was not replaced. Results although the duration of follow-up differed between the three groups, the clinical and radiological results at final follow-up showed no revision of femoral and/or tibial components for mechanical or septic reasons, and no signs of impending failure. One meniscal bearing, showing polyethylene wear after 17 years, was successfully replaced. Conclusions the present retrospective study confirmed the long-term effectiveness of knee implants with mobile bearings, in which the congruity of the surfaces makes it possible to overcome the problem of high contact stresses that may result in polyethylene wear and osteolysis; at the same time, these implants eliminate constraint forces thereby reducing the risk of mechanical loosening. Level of evidence Level III, retrospective comparative study. PMID:25606553

SOLARINO, GIUSEPPE; SPINARELLI, ANTONIO; CARROZZO, MASSIMILIANO; PIAZZOLLA, ANDREA; VICENTI, GIOVANNI; MORETTI, BIAGIO

2014-01-01

294

Does combining the results from multiple bone sites measured by a new quantitative ultrasound device improve discrimination of hip fracture?  

PubMed

There is a growing interest in the use of quantitative ultrasound (QUS) measurements as an alternative to current radiation-based bone densitometry techniques for the noninvasive assessment of fracture risk. While most of the commercialized ultrasound devices measure only single predefined peripheral skeletal sites, the Omnisense prototype (Sunlight Ltd., Israel) can be used on multiple bones, including the spinous processes. In this study, we examined the ability of speed of sound measured at the calcaneus, distal third and ultradistal radius, proximal third phalanx, metacarpal, capitate, patella, and the posterior process of the thoracic spine to differentiate subjects with hip fractures from normal controls. Seventy-nine postmenopausal Caucasian Israeli women who had sustained an atraumatic fracture of the proximal femur within the last 6 months were recruited from the local population (mean age 80 +/- 8.9 years). As controls, 295 postmenopausal Caucasian Israeli women without osteoporotic fractures were also included (mean age 70 +/- 8.7 years). Discrimination of hip fractures with QUS at all ultrasound sites was highly statistically significant (p < 0.01) (odds ratios [ORs] = 1.4-3.0; area under the ROC curve [AUC] 77-92%), except for the hand metacarpal. Distal radius and calcaneus measurements (ORs = 2.4 and 3.0) were the best discriminators of hip fracture patients from controls. Using a forward selective linear regression model, the discriminator values of combined assessment at two sites were investigated. There was moderate improvement in diagnostic value, but the best combination was the calcaneus with the distal radius, which improved the AUC by 3% and raised both the sensitivity and specificity to 94%. These data demonstrate the encouraging potential of improving discrimination of hip fracture by using multiple-site ultrasonic measurements. PMID:10234587

Hans, D; Srivastav, S K; Singal, C; Barkmann, R; Njeh, C F; Kantorovich, E; Glüer, C C; Genant, H K

1999-04-01

295

DTI-based muscle fiber tracking of the quadriceps mechanism in lateral patellar dislocation  

PubMed Central

Purpose To determine the feasibility of utilizing diffusion tensor MRI (DT-MRI) based muscle fiber tracking to create biomechanical models of the quadriceps mechanism in healthy subjects and those with chronic lateral patellar dislocation (LPD). Materials and Methods Four healthy (average 14.5 years old; BMI 21.8) and four chronic LPD (average 17.3 years old; BMI 22.4) females underwent DT and axial T1W MRI of the thighs. The anatomical and physiologic cross sectional areas (ACSA and PCSA, respectively) and pennation angle were calculated of the vastus lateralis oblique (VLO) and vastus medialis oblique (VMO) muscles. The predicted resultant force vector on the patella was calculated. Results The VLO pennation angles in healthy and LPD subjects were 18.7 and 14.5°, respectively (p=0.141). The VMO pennation angles in healthy and LPD subjects were 11.4 and 14.8°, respectively (p=0.02). The ACSA and PCSA VLO:VMO ratios in healthy and LPD subjects were 1.9:1.6 and 2.1:1.6, respectively (p=0.025 and 0.202, respectively). Regardless of whether ACSA or PCSA was used to predict resultant lateral force vectors, the values differed between healthy and LPD subjects (~2 and ~5.3°, respectively; p<0.05). Conclusion Chronic LPD patients had more laterally directed predicted resultant force vectors than healthy subjects. Our preliminary results suggest that biomechanical models of the quadriceps mechanism in patients with chronic LPD and healthy subjects can be created in healthy subjects and patients with chronic LPD using DT-MRI. PMID:19243049

Kan, J. Herman; Heemskerk, Anneriet M.; Ding, Zhaohua; Gregory, Andrew; Mencio, Gregory; Spindler, Kurt; Damon, Bruce M

2009-01-01

296

Dual Inversion Recovery Ultrashort Echo Time (DIR-UTE) Imaging and Quantification of the Zone of Calcified Cartilage (ZCC)  

PubMed Central

OBJECTIVE To develop ultrashort echo time (UTE) magnetic resonance imaging (MRI) techniques to image the zone of calcified cartilage (ZCC), and quantify its T2*, T1 and T1?. DESIGN In this feasibility study a dual inversion recovery ultrashort echo time (DIR-UTE) sequence was developed for high contrast imaging of the ZCC. T2* of the ZCC was measured with DIR-UTE acquisitions at progressively increasing TEs. T1 of the ZCC was measured with saturation recovery UTE acquisitions at progressively increasing saturation recovery times. T1? of the ZCC was measured with spin-locking prepared DIR-UTE acquisitions at progressively increasing spin-locking times. RESULTS The feasibility of the qualitative and quantitative DIR-UTE techniques was demonstrated on phantoms and in six cadaveric patellae using a clinical 3T scanner. On average the ZCC has a short T2* ranging from 1.0 to 3.3 ms (mean ± standard deviation = 2.0 ± 1.2 ms), a short T1 ranging from 256 to 389 ms (mean ± standard deviation = 305 ± 45 ms), and a short T1? ranging from 2.2 to 4.6 ms (mean ± standard deviation = 3.6 ± 1.2 ms). CONCLUSION UTE MR based techniques have been developed for high resolution imaging of the ZCC and quantitative evaluation of its T2*, T1 and T1? relaxation times, providing noninvasive assessment of collagen orientation and proteoglycan content at the zone of calcified cartilage and the bone cartilage interface. These measurements may be useful for non-invasive assessment of the ZCC, including understanding the involvement of this tissue component in osteoarthritis. PMID:23025927

Du, Jiang; Carl, Michael; Bae, Won C.; Statum, Sheronda; Chang, Eric; Bydder, Graeme M; Chung, Christine B.

2012-01-01

297

Painful knee joint after ACL reconstruction using biodegradable interference screws- SPECT/CT a valuable diagnostic tool? A case report  

PubMed Central

With the presented case we strive to introduce combined single photon emission computerized tomography and conventional computer tomography (SPECT/CT) as new diagnostic imaging modality and illustrate the possible clinical value in patients after ACL reconstruction. We report the case of a painful knee due to a foreign body reaction and delayed degradation of the biodegradable interference screws after ACL reconstruction. The MRI showed an intact ACL graft, a possible tibial cyclops lesion and a patella infera. There was no increased fluid collection within the bone tunnels. The 99mTc-HDP-SPECT/CT clearly identified a highly increased tracer uptake around and within the tibial and femoral tunnels and the patellofemoral joint. On 3D-CT out of the SPECT/CT data the femoral graft attachment was shallow (50% along the Blumensaat's line) and high in the notch. At revision arthroscopy a diffuse hypertrophy of the synovium, scarring of the Hoffa fat pad and a cyclops lesion of the former ACL graft was found. The interference screws were partially degraded and under palpation and pressure a grey fluid-like substance drained into the joint. The interference screws and the ACL graft were removed and an arthrolysis performed. In the case presented it was most likely a combination of improper graft placement, delayed degradation of the interference screws and unknown biological factors. The too shallow and high ACL graft placement might have led to roof impingement, chronic intraarticular inflammation and hence the delayed degradation of the screws. SPECT/CT has facilitated the establishment of diagnosis, process of decision making and further treatment in patients with knee pain after ACL reconstruction. From the combination of structural (tunnel position in 3D-CT) and metabolic information (tracer uptake in SPECT/CT) the patient's cause of the pain was established. PMID:20846410

2010-01-01

298

Graft selection in anterior cruciate ligament reconstruction.  

PubMed

Selecting the appropriate graft for ACL reconstruction depends on numerous factors including surgeon philosophy and experience, tissue availability (affected by anatomical anomalies or prior injury or surgery), and patient activity level and desires. Although the patella tendon autograft has the widest experience in the literature, and is probably the most commonly used graft source, this must be tempered with the higher reported incidences of potential morbidity and pitfalls associated with its use. The hamstring tendons are gaining increasing popularity, mostly due to reduced harvest morbidity and improved soft tissue fixation techniques, and many recent studies in the literature report equal results to BTB ACL reconstruction with respect to functional outcome and patient satisfaction. On the other hand, many of these studies report higher degrees of instrument (KT-100) tested laxity for hamstring reconstruction, and some have reported lower returns to preinjury levels of activity. One question that remains to be addressed is how closely objectively measured laxity tests correlate with subjectively assessed outcomes and ability to return to high levels of competitive sports. Allograft use, which decreased in popularity during the 1990s, appears to be undergoing a resurgence, with better sterilization processes and new graft sources (tibialis tendons), leading to increased availability and improved fixation techniques. The benefits of decreased surgical morbidity and easier rehabilitation must be weighed against the potential for greater failure of biologic incorporation, infection, and possibly slower return to activities. In our practice, for high-demand individuals (those playing cutting, pivoting, or jumping sports and skiing) BTB tends to be the graft of choice. For lower demand or older individuals, hamstring reconstructions will be performed. Allograft tissue will be used in older individuals (generally over 45 years old), those with signs of arthritis (and compelling evidence of instability), or those individuals who understand the pros and cons of allograft use fully and do not want their own tissue used. PMID:12528909

Miller, Suzanne L; Gladstone, James N

2002-10-01

299

COMPARISON OF CARTILAGE HISTOPATHOLOGY ASSESSMENT SYSTEMS ON HUMAN KNEE JOINTS AT ALL STAGES OF OSTEOARTHRITIS DEVELOPMENT  

PubMed Central

Objective To compare the MANKIN and OARSI cartilage histopathology assessment systems using human articular cartilage from a large number of donors across the adult age spectrum representing all levels of cartilage degradation. Design Human knees (n=125 from 65 donors; age range 23–92) were obtained from tissue banks. All cartilage surfaces were macroscopically graded. Osteochondral slabs representing the entire central regions of both femoral condyles, tibial plateaus, and the patella were processed for histology and Safranin O – Fast Green staining. Slides representing normal, aged, and OA tissue were scanned and electronic images were scored online by five observers. Statistical analysis was performed for inter- and intra-observer variability, reproducibility and reliability. Results The inter-observer variability among five observers for the MANKIN system showed a similar good intra-class coefficient (ICC >0.81) as for the OARSI system (ICC >0.78). Repeat scoring by three of the five readers showed very good agreement (ICC >0.94). Both systems showed a high reproducibility among four of the five readers as indicated by the Spearman’s rho value. For the MANKIN system, the surface represented by lesion depth was the parameter where all readers showed an excellent agreement. Other parameters such as cellularity, Safranin O staining intensity and tidemark had greater inter-reader disagreement. Conclusion Both scoring systems were reliable but appeared too complex and time consuming for assessment of lesion severity, the major parameter determined in standardized scoring systems. To rapidly and reproducibly assess severity of cartilage degradation, we propose to develop a simplified system for lesion volume. PMID:22353747

Pauli, C.; Whiteside, R.; Heras, F. Las; Nesic, D.; Koziol1, J.; Grogan, S.P.; Matyas, J.; Pritzker, K.P.H.; D’Lima, D.D.; Lotz, M.K.

2012-01-01

300

Correlation between radiographically diagnosed osteophytes and magnetic resonance detected cartilage defects in the patellofemoral joint  

PubMed Central

OBJECTIVE—To assess the correlation between radiographically diagnosed osteophytes in the axial and lateral view of the patellofemoral joint (PFJ) and (1) magnetic resonance (MR) detected cartilage defects in the same joint and (2) knee pain.?METHODS—Fifty seven pepole with chronic knee pain, (aged 41-58 years, mean 50 years) were examined with axial and lateral radiograms when standing of the right and the left PFJ. The presence and grade of osteophytes was assessed. On the same day, a MR examination was performed of the signal knee with proton density and T2 weighted turbo spin-echo sequences in the sagittal and axial view on a 1.0 T imager. Cartilage defects in the PFJ were noted. The subjects were questioned for current knee pain for each knee.?RESULTS—Osteophytes at the PFJ had a specificity varying between 59 and 100% and a positive predictive value between 74 and 100% for MR detected cartilage defects. The corresponding values for osteophytes at the lateral aspect of the femoral trochlea were both 100%. In PFJ with narrowing (<5 mm) osteophytes had a sensitivity and a positive predictive value of 90 and 95% respectively for MR detected cartilage defects, while in PFJ with non-narrowing (?5 mm) the corresponding values were 75 and 65% and the specificity was 50%. A correlation (p<0.05) between osteophytes at the inferior pole of the patella and knee pain was found.?CONCLUSIONS—Osteophytes at the PFJ are associated with MR detected cartilage defects in the same joint. The relation was strong for osteophytes at the lateral femoral trochlea and in the PFJ with narrowing (<5 mm), but weak in the PFJ with non-narrowing (?5 mm). ?? Keywords: knee; radiograms; osteoarthritis; osteophyte PMID:9797565

Boegard, T; Rudling, O; Petersson, I; Jonsson, K

1998-01-01

301

Metal-binding proteins as metal pollution indicators  

SciTech Connect

The fact that metal-binding proteins are a consequence of elevated metal concentration in organisms is well known. What has been overlooked is that the presence of these proteins provides a unique opportunity to reformulate the criteria of metal pollution. The detoxification effect of metal-binding proteins in animals from polluted areas has been cited, but there have been only very few studies relating metal-binding proteins to pollution. This lack is due partly to the design of most experiments, which were aimed at isolation of metal-binding proteins and hence were of too short duration to allow for correlation to adverse physiological effects on the organism. In this study metal-binding proteins were isolated and characterized from five different marine animals (rock lobster, Jasus lalandii; hermit crab, Diogenes brevirostris; sandshrimp, Palaemon pacificus; black mussel, Choromytilus meridionalis; and limpet, Patella granularis). These animals were kept under identical metal-enriched conditions, hence eliminating differences in method and seasons. The study animals belonged to different phyla; varied in size, mass, age, behavior, food requirements and life stages; and accumulated metals at different rates. It is possible to link unseasonal moulting in crustacea, a known physiological effect due to a metal-enriched environment, to the production of the metal-binding protein without evidence of obvious metal body burden. Thus a new concept of pollution is defined: the presence of metal-binding proteins confirms toxic metal pollution. This concept was then tested under field conditions in the whelk Bullia digitalis and in metal-enriched grass.

Hennig, H.F.

1986-03-01

302

Controlling factors of recent clastic coastal sediments (Viransehir, Mersin bay, S Turkey)  

NASA Astrophysics Data System (ADS)

The Plio-Quaternary conglomeratic sets within the marine environment of the Viran?ehir coast (W Mersin, S Turkey) are responsible for the evolution of sandy and gravely beaches due to their control on various factors such as sea floor irregularity, wave energy, and organic activity. The conglomeratic sets close to the shoreline (50-150 cm) act as wave breakers, creating hard substratum and high energy, well-oxygenated environment for organisms like Patella sp., Phoronida worms and Brachidontes pharaonis (Fischer P. 1870). The boring activities of these organisms have disintegrated the sandy matrix of these sets. Finer-grained matrix sediments have been transported to the interset and open sea, while cobble-pebbles have been carried landwards and have created imbricated gravely beach deposits without matrix. Sandy beach is evolving where the conglomeratic sets away from the shoreline (5.0-10.0 m). In this example, sets form a bar; causing fivefold division as backshore, berm, surf zone, bar and offshore from land to sea. Poorly sorted, cobbles-pebbles cobbles and pebbles are found associated with the high-energy environments of bars, whilst well-sorted sands are observed in low energetic environments on shore. The sets and recent shell fragments are the main sources of coastal sediments in Viran?ehir. However, the amount of shell fragments decrease towards the active river mouth. This is due to sediment and fresh water influx from the river causing deteriorated temperature, salinity and light penetration of the marine environment resulting in less organic diversity.

Gül, Murat; Özbek, Ahmet; Kurt, Mehmet Ali; Zorlu, Kemal

2009-04-01

303

Reevaluation of (241)Am content in the USTUR case 0102 leg phantom.  

PubMed

The (241)Am contents in the United States Transuranium and Uranium Registries' (USTUR) case 0102 leg phantom were previously estimated to be 1,243 ± 11 Bq. Recent analysis of the computed tomography images of the phantom revealed multiple bone structures missing from various regions of the phantom skeleton including: posterior ilium, anterior ilium, ischium, femur proximal end, femur middle shaft, femur distal end, patella, tibia distal shaft, fibula distal shaft, and fibula distal end. Additionally, the fifth metatarsal and all of the fifth-digit phalanges were found to be completely missing from the foot. A three-dimensional (3D) model of the leg phantom was created using 3D-Doctor software. Volumes of missing bone structures were outlined separately based on the anatomical assessment of those structures. Weights of the missing bone samples were calculated. Consequently, the value of total( 241)Am activity in the USTUR leg phantom is 1,218 ± 11 Bq. This activity is about 2.0% less than the previously published value of 1,243 ± 11 Bq. External gamma detector response was simulated considering both activity values (1,243 and 1,218 Bq) across the five different locations along the USTUR leg phantom: foot, middle leg, knee, middle thigh, and hip. Each counting position was chosen such that it was above the missing bone structure locations. The highest difference observed between the two counting efficiencies (each corresponding to the two different quantities of estimated activity) was 8.2% and 9.4% for locations above the foot and middle thigh, respectively. Other counting locations (middle leg, knee, and hip) showed efficiency variations of about 1%. PMID:23326860

Tabatadze, George; Brey, Richard R; Kramer, Gary H; Capello, Kevin; Meldrum, D Jeffrey

2013-01-01

304

[Ultrasound image of the Lachman test in lesions of the anterior cruciate ligament].  

PubMed

The sonographic examination of the knee-joint can, in many pathological alterations of the knee-joint, supply additional informations. In the standardized ultrasound examination of the knee-joint ventral and dorsal sectional planes will be adjusted (4, 7, 14, 17). For the examination of the lesions of the anterior cruciate ligament direct adjustment techniques in the aere of origin of the anterior cruciate ligament (15, 16) and indirect examination methods are known (7, 8, 9, 20). While Hien chose a direct medial parapatellaric horizontal sagittal sectional plane in the course of the lig. patellae (8), we carry out our examination in a ventral infrapatellaric sagittal plane. The examinations were conducted with an ultrasound unit of the type Siemens Sonoline SL 2 with a linear transducer with a frequency of 5 MHz without a stand off pad. In the course of a prospective clinical examination an anteromedial test of stability of both knee-joints was conducted on 360 patients with the help of a sonographic Lachman-test. Two examination groups were formed: in group 1 60 patients with a arthroscopically secured lesion of the anterior cruciate ligament were registered and set against 300 probationers with "empty" anamnesis of the knee-joint of group 2. In the group of patients with a cruciate ligament injury a tibia translation of 5.3 mm in the Lachman-test was found; the side difference between the leg injured and the one uninjured amounted to 3.0 mm. In the control group the tibia translation amounted to 2.9 mm with a side difference of 0.9 mm.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1411918

Gruber, G; Harland, U; Gruber, G M

1992-09-01

305

Skin tension related to tension reduction sutures.  

PubMed

The aim of this study was to compare the skin tension of several fascial/subcutaneous tensile reduction sutures. Six upper limbs and 8 lower limbs of 4 fresh cadavers were used. At the deltoid area (10 cm below the palpable acromion) and lateral thigh (midpoint from the palpable greater trochanter to the lateral border of the patella), and within a 3 × 6-cm fusiform area of skin, subcutaneous tissue defects were created. At the midpoint of the defect, a no. 5 silk suture was passed through the dermis at a 5-mm margin of the defect, and the defect was approximated. The initial tension to approximate the margins was measured using a tensiometer.The tension needed to approximate skin without any tension reduction suture (S) was 6.5 ± 4.6 N (Newton). The tensions needed to approximate superficial fascia (SF) and deep fascia (DF) were 7.8 ± 3.4 N and 10.3 ± 5.1 N, respectively. The tension needed to approximate the skin after approximating the SF was 4.1 ± 3.4 N. The tension needed to approximate the skin after approximating the DF was 4.9 ± 4.0 N. The tension reduction effect of approximating the SF was 38.8 ± 16.4% (2.4 ± 1.5 N, P = 0.000 [ANOVA, Scheffé]). The tension reduction effect of approximating the DF was 25.2% ± 21.9% (1.5 ± 1.4 N, P = 0.001 [ANOVA, Scheffé]). The reason for this is thought to be that the SF is located closely to the skin unlike the DF. The results of this study might be a basis for tension reduction sutures. PMID:25569413

Hwang, Kun; Kim, Han Joon; Kim, Kyung Yong; Han, Seung Ho; Hwang, Se Jin

2015-01-01

306

Extended Healing Validation of an Artificial Tendon to Connect the Quadriceps Muscle to the Tibia: 180-day Study  

PubMed Central

Whenever a tendon or its bone insertion is disrupted or removed, existing surgical techniques provide a temporary connection or scaffolding to promote healing, but the interface of living to nonliving materials soon breaks down under the stress of these applications, if it must bear the load more than acutely. Patients are thus disabled whose prostheses, defect size, or mere anatomy limit the availability or outcomes of such treatments. Our group developed the OrthoCoupler™ device to join skeletal muscle to prosthetic or natural structures without this interface breakdown. In this study, the goat knee extensor mechanism (quadriceps tendon, patella, and patellar tendon) was removed from the right hind limb in 16 goats. The device connected the quadriceps muscle to a stainless steel bone plate on the tibia. Mechanical testing and histology specimens were collected from each operated leg and contra lateral unoperated control legs at 180 days. Maximum forces in the operated leg (vs. unoperated) were 1400± 93N (vs. 1179± 61 N), linear stiffnesses were 33± 3 N/mm (vs. 37 ± 4N/mm), and elongations at failure were 92.1 ± 5.3 mm (vs. 68.4 ± 3.8 mm; mean ± SEM). Higher maximum forces (p = 0.02) and elongations at failure (p = 0.008) of legs with the device versus unoperated controls were significant; linear stiffnesses were not (p = 0.3). We believe this technology will yield improved procedures for clinical challenges in orthopaedic oncology, revision arthroplasty, tendon transfer, and tendon injury reconstruction. PMID:22179930

Melvin, Alan J.; Litsky, Alan S.; Mayerson, Joel L.; Stringer, Keith; Juncosa-Melvin, Natalia

2011-01-01

307

Osteoarthritis of the knee at 3.0 T: comparison of a quantitative and a semi-quantitative score for the assessment of the extent of cartilage lesion and bone marrow edema pattern in a 24-month longitudinal study  

PubMed Central

Objective To compare a semi-quantitative and a quantitative morphological score for assessment of early osteoarthritis (OA) evolution. Materials and methods 3.0 T MRI of the knee was performed in 60 women, 30 with early OA (each 15 with Kellgren–Lawrence grade 2 and 3) and 30 age-matched controls at baseline and at 12 and 24 months. Pathological condition was assessed with the whole-organ magnetic resonance imaging score (WORMS). Cartilage abnormalities and bone marrow edema pattern (BMEP) were also quantified using a previously introduced morphological quantitative score. These data were correlated with changes in clinical parameters and joint space width using generalized estimation equations (GEE). Results At baseline, OA patients had significantly (p<0.05) more and larger cartilage lesions and BMEP. During follow-up, cartilage lesions increased significantly (p<0.05) in the patients compared with controls: WORMS showed progression only at the lateral patella, whereas the quantitative score revealed progression additionally at the trochlea and at the medial compartment. Both scores showed a significant (p<0.05) increase in BMEP at the lateral femur in OA patients. In addition, quantitative scores of BMEP of the whole knee decreased significantly (p<0.05) after 12 months and increased after 24 months in the patients, but showed an increase in controls at all follow-up examinations. Only weak correlations between structural imaging findings and clinical parameters were observed. Conclusion Quantitative assessment of cartilage lesions and BMEP is more sensitive to changes during the course of the disease than semi-quantitative scoring. However, structural imaging findings do not correlate well with the clinical progression of OA. PMID:21479518

Jain, Sapna K.; Lutz, Jürgen; Wyman, Bradley T.; Le Graverand-Gastineau, Marie-Pierre Hellio; Vignon, Eric; Majumdar, Sharmila; Link, Thomas M.

2012-01-01

308

Modification of the association between lead exposure and amyotrophic lateral sclerosis by iron and oxidative stress related gene polymorphisms.  

PubMed

Our objective was to examine whether functional polymorphisms in hemochromatosis (HFE; H63D and C282Y), transferrin (TfC2), and glutathione-s-transferase Pi1 (GSTP1; Ile105Val) genes modify any lead-ALS association. We measured blood lead using atomic absorption spectroscopy and bone lead - a biomarker of cumulative lead exposure - using K-shell-X-ray fluorescence in 100 neurologist-confirmed ALS cases and 194 controls, the latter recruited as part of two separate studies; all subjects lived in New England. Participants were considered variant carriers or wild-type for each polymorphism. To assess effect modification, we included cross-product terms between lead biomarkers and each polymorphism in separate adjusted polytomous logistic regression models. Compared with wild-type, the odds ratio (OR) per 15.6 ?g/g patella lead (interquartile range; IQR) was 8.24 (95% CI 0.94-72.19) times greater among C282Y variant carriers, and 0.34 (95% CI 0.15-0.78) times smaller among H63D variant carriers. Results were weaker for tibia lead. Compared with wild-type the OR per 2 ?g/dl blood lead (IQR) was 0.36 (95% CI 0.19-0.68) times smaller among H63D variant carriers, and 1.96 (95% CI 0.98-3.92) times greater among GSTP1 variant carriers. In conclusion, we found that HFE and GSTP1 genotypes modified the association between lead biomarkers and ALS. Contrasting modification by the HFE polymorphisms H63D and C282Y may suggest that the modification is not simply the result of increased iron. PMID:25293352

Eum, Ki-Do; Seals, Ryan M; Taylor, Kathryn M; Grespin, Matthew; Umbach, David M; Hu, Howard; Sandler, Dale P; Kamel, Freya; Weisskopf, Marc G

2014-10-01

309

Marine molluscs as biomonitors for heavy metal levels in the Gulf of Suez, Red Sea  

NASA Astrophysics Data System (ADS)

Levels of the heavy metals Copper (Cu), Zinc (Zn), Lead (Pb), Cadmium (Cd), Chromium (Cr), Nickel (Ni), Iron (Fe) and Manganese (Mn) were determined in coastal water, sediments and soft tissues of the gastropod limpet, Patella caerulea, and the bivalve, Barbatus barbatus, from seven different stations in the western coast of the Gulf of Suez. The concentrations of heavy metals in water ranged between 3.37-4.78, 18.83-21.46, 2.75-3.17, 0.22-0.27, 0.99-1.21, 2.69-3.65, 3.75-4.56 ?g L - 1 and 23.82-32.78 mg g - 1 for Cu, Zn, Pb, Cd, Cr, Ni, Mn and Fe, respectively. The corresponding concentration values in the sediments were 8.65-12.16, 51.78-58.06, 36.52-42.15, 3.23-3.98, 9.03-12.75, 34.31-49.63, 3.28-4.56 and 64.20-70.22 ?g g - 1 for Cu, Zn, Pb, Cd, Cr, Ni, Mn and Fe, respectively. The highest accumulated metals were Fe, Zn and Mn in both P. caerulea and B. barbatus, while the lowest one was Cd. The accumulation of metals was more pronounced in P. caerulea than B. barbatus. The highest concentrations of all metals in water, sediments and mollusca were recorded at Adabiya harbour north of the Gulf, while the lowest concentrations were recorded at Gabal El-Zeit and Hurghada. Land based activities and ships awaiting berth are the main source of metal pollution in the northern part of the Gulf.

Hamed, Mohamed A.; Emara, Ahmed M.

2006-05-01

310

Minimum 5-year Follow-up Results of Minimally Invasive Total Knee Arthroplasty Using Mini-Keel Modular Tibial Implant  

PubMed Central

Purpose To evaluate the minimum 5-year mid-term clinical and radiological results of minimally invasive surgery total knee arthroplasty (MIS-TKA) using a mini-keel modular tibia component. Materials and Methods We retrospectively evaluated 254 patients (361 cases) who underwent MIS-TKA between 2005 and 2006. The latest clinical and radiological assessments were done in 168 cases that had been followed on an outpatient basis for more than 5 postoperative years. Clinical results were assessed using the Hospital for Special Surgery (HSS) score and Knee Society score. Radiological evaluation included measurements of knee alignment. Results The average postoperative knee range of motion and HSS score were 134.3°±12.4° and 92.7°±7.0°, respectively. The average postoperative femorotibial angle and tibial component alignment angle were 5.2°±1.7° valgus and 90.2°±1.6°, respectively. The average tibial component posterior inclination was 4.8°±2.1°. The percentage of cases with tibial component alignment angle of 90°±3° was 96.1%, and that with the femorotibial angle of 6°±3° valgus was 94.0%. Radiolucent lines were observed in 20 cases (12.0%): around the femur, tibia, and patella in 14 cases, 10 cases, and 1 case, respectively. However, they were less than 2 mm and non-progressive in all cases. The survival rate was 99.4% and there was no implant-related revision. Conclusions MIS-TKA using a mini-keel modular tibial plate showed satisfactory results, a high survival rate, and excellent clinical and radiological results in the mid-term follow-up. PMID:25229044

Yoo, Ju-Hyung; Park, Byoung-Kyu; Han, Chang-Dong; Oh, Hyun-Cheol

2014-01-01

311

Patellar Skin Surface Temperature by Thermography Reflects Knee Osteoarthritis Severity  

PubMed Central

Background: Digital infrared thermal imaging is a means of measuring the heat radiated from the skin surface. Our goal was to develop and assess the reproducibility of serial infrared measurements of the knee and to assess the association of knee temperature by region of interest with radiographic severity of knee Osteoarthritis (rOA). Methods: A total of 30 women (15 Cases with symptomatic knee OA and 15 age-matched Controls without knee pain or knee OA) participated in this study. Infrared imaging was performed with a Meditherm Med2000™ Pro infrared camera. The reproducibility of infrared imaging of the knee was evaluated through determination of intraclass correlation coefficients (ICCs) for temperature measurements from two images performed 6 months apart in Controls whose knee status was not expected to change. The average cutaneous temperature for each of five knee regions of interest was extracted using WinTes software. Knee x-rays were scored for severity of rOA based on the global Kellgren-Lawrence grading scale. Results: The knee infrared thermal imaging procedure used here demonstrated long-term reproducibility with high ICCs (0.50–0.72 for the various regions of interest) in Controls. Cutaneous temperature of the patella (knee cap) yielded a significant correlation with severity of knee rOA (R = 0.594, P = 0.02). Conclusion: The skin temperature of the patellar region correlated with x-ray severity of knee OA. This method of infrared knee imaging is reliable and as an objective measure of a sign of inflammation, temperature, indicates an interrelationship of inflammation and structural knee rOA damage. PMID:21151853

Denoble, Anna E.; Hall, Norine; Pieper, Carl F.; Kraus, Virginia B.

2010-01-01

312

An Artificial Tendon to Connect the Quadriceps Muscle to the Tibia  

PubMed Central

No permanent, reliable artificial tendon exists clinically. Our group developed the OrthoCoupler™ device as a versatile connector, fixed at one end to a muscle, and adaptable at the other end to inert implants such as prosthetic bones or to bone anchors. The objective of this study was to evaluate four configurations of the device to replace the extensor mechanism of the knee in goats. Within muscle, the four groups had: (A) needle-drawn uncoated bundles, (B) needle-drawn coated bundles, (C) barbed uncoated bundles, and (D) barbed coated bundles. The quadriceps tendon, patella, and patellar tendon were removed from the right hind limb in 24 goats. The four groups (n=6 for each) were randomly assigned to connect the quadriceps muscle to the tibia (with a bone plate). Specimens were collected from each operated leg and contralateral unoperated controls both for mechanical testing and histology at 90 days post-surgery. In strength testing, maximum forces in the operated leg (vs. unoperated control) were 1288±123 N (vs. 1387±118 N) for group A, 1323±144 N (vs. 1396±779 N) for group B, 930±125 N (vs. 1337±126 N) for group C, and 968±109 N (vs. 1528±146 N) for group D (mean ± SEM). The strengths of the OrthoCoupler™ legs in the needled device groups were equivalent to unoperated controls (p=0.6), while both barbed device groups had maximum forces significantly lower than their controls (p=0.001). We believe this technology will yield improved procedures for clinical challenges in orthopaedic oncology, revision arthroplasty, tendon transfer, and tendon injury reconstruction. PMID:21520259

Melvin, Alan; Litsky, Alan; Mayerson, Joel; Stringer, Keith; Melvin, David; Juncosa-Melvin, Natalia

2011-01-01

313

Metal-binding proteins as metal pollution indicators.  

PubMed Central

The fact that metal-binding proteins are a consequence of elevated metal concentration in organisms is well known. What has been overlooked is that the presence of these proteins provides a unique opportunity to reformulate the criteria of metal pollution. The detoxification effect of metal-binding proteins in animals from polluted areas has been cited, but there have been only very few studies relating metal-binding proteins to pollution. This lack is due partly to the design of most experiments, which were aimed at isolation of metal-binding proteins and hence were of too short duration to allow for correlation to adverse physiological effects on the organism. In this study metal-binding proteins were isolated and characterized from five different marine animals (rock lobster, Jasus lalandii; hermit crab, Diogenes brevirostris; sandshrimp, Palaemon pacificus; black mussel, Choromytilus meridionalis; and limpet, Patella granularis). These animals were kept under identical metal-enriched conditions, hence eliminating differences in method and seasons. The study animals belonged to different phyla; varied in size, mass, age, behavior, food requirements and life stages; and accumulated metals at different rates. It is possible to link unseasonal moulting in crustacea, a known physiological effect due to a metal-enriched environment, to the production of the metal-binding protein without evidence of obvious metal body burden. Thus a new concept of pollution is defined: the presence of metal-binding proteins confirms toxic metal pollution. This concept was then tested under field conditions in the whelk Bullia digitalis and in metal-enriched grass. PMID:3709437

Hennig, H F

1986-01-01

314

Quantification of stiffness change in degenerated articular cartilage using optical coherence tomography-based air-jet indentation.  

PubMed

Articular cartilage is a thin complex tissue that covers the bony ends of joints. Changes in the composition and structure of articular cartilage will cause degeneration, which may further lead to osteoarthritis. Decreased stiffness is one of the earliest symptoms of cartilage degeneration and also represents the imperfect quality of repaired cartilage. An optical coherence tomography (OCT)-based air-jet indentation system was recently developed in our group to measure the mechanical properties of soft tissues. In this study, this system was applied to quantify the change of mechanical properties of articular cartilage after degeneration induced by enzymatic digestions. Forty osteochondral disks (n = 20 × 2) were prepared from bovine patellae and treated with collagenase and trypsin digestions, respectively. The apparent stiffness of the cartilage was measured by the OCT-based air-jet indentation system before and after the degeneration. The results were also compared with those from a rigid contact mechanical indentation and an ultrasound water-jet indentation. Through the air-jet indentation, it was found that the articular cartilage stiffness dropped significantly by 84% (p < 0.001) and 63% (p < 0.001) on average after collagenase and trypsin digestions, respectively. The stiffness measured by the air-jet indentation system was highly correlated (R > 0.8, p < 0.001) with that from the other two indentation methods. This study demonstrated that the OCT-based air-jet indentation can be a useful tool to quantitatively assess the mechanical properties of articular cartilage, and this encourages us to further develop a miniaturized probe suitable for arthroscopic applications. PMID:21591927

Huang, Yan-Ping; Wang, Shu-Zhe; Saarakkala, Simo; Zheng, Yong-Ping

2011-10-01

315

The clinical significance, natural history and predictors of bone marrow lesion change over eight years  

PubMed Central

Introduction There is increasing evidence to suggest that bone marrow lesions (BMLs) play a key role in the pathogenesis of osteoarthritis (OA). However, there is a lack of long term data. The aim of this study was to describe the natural history of knee BMLs, their association with knee pain and examine predictors of BML change over eight years. Methods A total of 198 subjects (109 adult offspring of subjects who had a knee replacement and 89 community-based controls) were studied. Knee pain and BML size were assessed at two and ten year visits. Results At the two year visit, 64% of participants (n?=?127) had 229 BMLs (34% patella, 26% femoral and 40% tibial). Over eight years, 24% (55/229) increased in size, 55% (125/229) remained stable and 21% (49/229) decreased in size or resolved completely. Of the participants without BMLs at baseline, 52% (37/71) developed incident BMLs. After adjusting for confounders, eight year change in total BML size was associated with change in knee pain in offspring (??=?2.50, 95% confidence interval (CI) 0.96 to 4.05) but not controls. This association was stronger in males. Incident BMLs were associated with increase in pain (??=?3.60, 95% CI 1.14 to 6.05). Body mass index (BMI) and strenuous activity (but not radiographic osteoarthritis or smoking) were associated with an increase in BML size. Conclusion In this midlife cohort, the proportion of BMLs increasing in size was similar to those decreasing in size with the majority remaining stable. Change in BMLs was predicted by BMI and strenuous activity. An increase in BML size or a new BML resulted in an increase in pain especially in males and those with a family history of OA. PMID:25022807

2014-01-01

316

Mobile-bearing total knee arthroplasty: a full traumatic rotation of 180°.  

PubMed

From February 2008 to September 2012 we implanted 204 mobile-bearing knee prostheses in 192 patients. All the prostheses were cemented (both femoral and tibial components), and the patella was not replaced. Only one early complication of the implants (1/204 = 0.004%) occurred after a traumatic event as a full 180° rotation of the mobile-bearing polyethylene insert. A 78-year-old woman presented with swelling and severe pain at her right knee. This traumatic event was the only case among our mobile-bearing insert patients. ?The failed polyethylene inserts were retrieved and studied using a scanning electron microscope (SEM, ZEISS EVO 50 EP, Cambridge, UK) operating at 20 kV. ?Scratching and pitting were found on the UHMWPE insert perpendicular to the machining tracks for the concave surface. SEM micrographs of the insert showed burnishing on the concave surfaces and longitudinal scratches were clearly detectable and well-marked on the analyzed surfaces. ?A traumatic, fully rotating, polyethylene insert is rare and our case is the first report describing a traumatic event with a complete 180 degree rotation mobile-bearing in a total knee prosthesis. ?In the literature few reports discuss clinical outcomes after total knee arthroplasty in patients with Parkinson's disease and they cite mixed results. However, some authors suggest that posterior-stabilized and cruciate-retaining TKA should work well while others prefer cruciate-retaining, condylar constrained kinetics, or hinged devices. Although we did not implant a posterior-stabilized mobile-bearing total knee prosthesis or a constrained prosthesis, we obtained good clinical and radiological results at the 2-year followup. PMID:23653296

Sudanese, Alessandra; Castiello, Emanuela; Affatato, Saverio

2013-06-25

317

Mechanisms of improved knee flexion after rectus femoris transfer surgery  

PubMed Central

Rectus femoris transfer is frequently performed to treat stiff-knee gait in subjects with cerebral palsy. In this surgery, the distal tendon is released from the patella and re-attached to one of several sites, such as the sartorius or the iliotibial band. Surgical outcomes vary, and the mechanisms by which the surgery improves knee motion are unclear. The purpose of this study was to clarify the mechanism by which the transferred muscle improves knee flexion by examining three types of transfers. Muscle-actuated dynamic simulations were created of ten children diagnosed with cerebral palsy and stiff-knee gait. These simulations were altered to represent surgical transfers of the rectus femoris to the sartorius and the iliotibial band. Rectus femoris transfers in which the muscle remained attached to the underlying vasti through scar tissue were also simulated by reducing but not eliminating the muscle’s knee extension moment. Simulated transfer to the sartorius, which converted the rectus femoris’ knee extension moment to a flexion moment, produced 32° ± 8° improvement in peak knee flexion on average. Simulated transfer to the iliotibial band, which completely eliminated the muscle’s knee extension moment, predicted only slightly less improvement in peak knee flexion (28° ± 8°). Scarred transfer simulations, which reduced the muscle’s knee extension moment, predicted significantly less (p < 0.001) improvement in peak knee flexion (14° ± 5°). Simulations revealed that improved knee flexion following rectus femoris transfer is achieved primarily by reduction of the muscle’s knee extension moment. Reduction of scarring of the rectus femoris to underlying muscles has the potential to enhance knee flexion. PMID:19217109

Fox, Melanie D.; Reinbolt, Jeffrey A.; Õunpuu, Sylvia; Delp, Scott L.

2010-01-01

318

Approximation of the functional kinematics of posterior stabilised total knee replacements using a two-dimensional sagittal plane patello-femoral model: comparing model approximation to in vivo measurement.  

PubMed

Previous in vivo studies have observed that current designs of posterior stabilised (PS) total knee replacements (TKRs) may be ineffective in restoring normal kinematics in Late flexion. Computer-based models can prove a useful tool in improving PS knee replacement designs. This study investigates the accuracy of a two-dimensional (2D) sagittal plane model capable of predicting the functional sagittal plane kinematics of PS TKR implanted knees against direct in vivo measurement. Implant constraints are often used as determinants of anterior-posterior tibio-femoral positioning. This allowed the use of a patello-femoral modelling approach to determine the effect of implant constraints. The model was executed using motion simulation software which uses the constraint force algorithm to achieve a solution. A group of 10 patients implanted with Scorpio PS implants were recruited and underwent fluoroscopic imaging of their knees. The fluoroscopic images were used to determine relative implant orientation using a three-dimensional reconstruction method. The determined relative tibio-femoral orientations were then input to the model. The model calculated the patella tendon angles (PTAs) which were then compared with those measured from the in vivo fluoroscopic images. There were no significant differences between the measured and calculated PTAs. The average root mean square error between measured and modelled ranged from 1.17° to 2.10° over the flexion range. A sagittal plane patello-femoral model could conceivably be used to predict the functional 2D kinematics of an implanted knee joint. This may prove particularly useful in optimising PS designs. PMID:24559039

Van Duren, Bernard; Pandit, Hemant; Murray, David; Gill, Harinderjit

2015-08-01

319

Profile and multidrug resistance determinants of Chryseobacterium indologenes from seawater and marine fauna.  

PubMed

The aim of this study was to investigate the prevalence and genetic basis of multidrug resistance in Chryseobacterium indologenes from seawater and marine invertebrates used for human consumption, in Kaštela Bay, Adriatic Sea, Croatia. Out of 16 samples of seawater, Mediterranean mussel (Mytilus galloprovincialis Lam.), Rayed Mediterranean limpets (Patella caerulea L.) and Purple sea urchins (Paracentrotus lividus Lam.) collected, 15 were positive for C. indologenes. In total, 41 isolates were randomly selected and tested for antibiotic susceptibility by disc-diffusion and broth microdilution methods. PCR was used to detect alleles encoding extended-spectrum (ESBLs) and metallo-?-lactamases (MBLs). The clonality of ?-lactamase-producing strains was evaluated by random amplified polymorphic DNA (RAPD) analysis. All C. indologenes isolates showed multiple resistance to at least 9 out of 16 antibiotics tested. Lowest resistance rates were found for piperacillin (9.7 %) and ciprofloxacin (24.4 %), whereas only piperacillin/tazobactam and trimethoprim/sulfamethoxazole showed 100 % activity. More than half of isolates carried bla (IND)-type gene, including 2 isolates carrying bla (IND-2) and 21 carrying bla (IND-7), that was identified as a major MBL genotype in isolates from Adriatic Sea. RAPD typing of IND-producing isolates revealed 6 major groups with no predominant clone in population. The presence of multidrug resistant and IND-producing C. indologenes in marine environment, including marine fauna, pose a risk for transmitting this opportunistic pathogen to humans through recreation or consummation of seafood. In addition, the antibiotic susceptibility test results have practical relevance for empirical treatment of C. indologenes infections. PMID:23132253

Maravi?, Ana; Sko?ibuši?, Mirjana; Samani?, Ivica; Puizina, Jasna

2013-03-01

320

Influence of aging on the in vivo properties of human patellar tendon.  

PubMed

Tendons are important for optimal muscle force transfer to bone and play a key role in functional ability. Changes in tendon properties with aging could contribute to declines in physical function commonly associated with aging. We investigated the in vivo mechanical properties of the patellar tendon in 37 men and women [11 young (27 +/- 1 yr) and 26 old (65 +/- 1 yr)] using ultrasonography and magnetic resonance imaging (MRI). Patella displacement relative to the tibia was monitored with ultrasonography during ramped isometric contractions of the knee extensors, and MRI was used to determine tendon cross-sectional area (CSA) and signal intensity. At peak force, patellar tendon deformation, stress, and strain were 13 (P = 0.05), 19, and 12% less in old compared with young (P < 0.05). Additionally, deformation, stiffness, stress, CSA, and length were 18, 35, 41, 28, and 11% greater (P < 0.05), respectively, in men compared with women. After normalization of mechanical properties to a common force, no age differences were apparent; however, stress and strain were 26 and 22% higher, respectively, in women compared with men (P < 0.05). CSA and signal intensity decreased 12 and 24%, respectively, with aging (P < 0.05) in the midregion of the tendon. These data suggest that differences in patellar tendon in vivo mechanical properties with aging are more related to force output rather than an age effect. In contrast, the decrease in signal intensity indirectly suggests that the internal milieu of the tendon is altered with aging; however, the physiological and functional consequence of this finding requires further study. PMID:18927271

Carroll, C C; Dickinson, J M; Haus, J M; Lee, G A; Hollon, C J; Aagaard, P; Magnusson, S P; Trappe, T A

2008-12-01

321

Modifying roles of glutathione S-transferase polymorphisms on the association between cumulative lead exposure and cognitive function  

PubMed Central

Background Glutathione-S-transferase gene (GST) polymorphisms can result in variable ability of these enzymes to remove electrophilic substrates. We investigated whether the GSTP1 Val105 and GSTM1 deletion polymorphisms modify the lead-cognitive function association. Methods We used repeated measures analysis to compare the association between cumulative lead biomarkers—bone lead measured using K-shell X-Ray Fluorescence—and Mini-Mental State Exam (MMSE) score by GST variants, adjusted for covariates, among Normative Aging Study participants, a Boston-based prospective cohort of men. We had complete data for 698 men (providing 1292 observations) for GSTM1 analyses and 595 men (providing 1142 observations) for GSTP1 analyses. Results A 15 ?g/g higher tibia lead concentration (interquartile range of tibia lead) was associated with a 0.24 point decrement in MMSE score among GSTP1 Val105 variant carriers, which was significantly stronger than the association among men with only wild-type alleles (p=0.01). The association among GSTP1 Val105 carriers was comparable to that of 3 years of age in baseline MMSE scores. The association between tibia lead and MMSE score appeared progressively steeper in participants with increasingly more GSTP1 Val105 alleles. A modest association between tibia lead and lower MMSE score was seen among participants with the GSTM1 deletion polymorphism. Neither of the glutathione S-transferase variants was independently associated with cognitive function, nor with lead biomarker measures. The results pertaining to patella lead were similar to those observed for tibia lead. Conclusion Our results suggest that the GSTP1 Val105 polymorphism confers excess susceptibility to the cognitive effects of cumulative lead exposure. PMID:23958642

Eum, Ki-Do; Wang, Florence T.; Schwartz, Joel; Hersh, Craig P.; Kelsey, Karl; Wright, Robert O.; Spiro, Avron; Sparrow, David; Hu, Howard; Weisskopf, Marc G.

2013-01-01

322

Anterior knee pain: an update of physical therapy.  

PubMed

Anterior knee pain is one of the most common knee problems in physically active individuals. The reason for anterior knee pain has been suggested to be multifactorial with patella abnormalities or extensor mechanism disorder leading to patellar malalignment during flexion and extension of the knee joint. Some patients complain mostly of non-specific knee pain, while others report patellar instability problems. The patients present with a variety of symptoms and clinical findings, meaning that a thorough clinical examination is the key for optimal treatment. Weakness of the quadriceps muscle, especially during eccentric contractions, is usually present in the majority of anterior knee pain patients. However, irrespective of whether pain or instability is the major problem, hypotrophy and reduced activity of the vastus medialis are often found, which result in an imbalance between vastus medialis and vastus lateralis. This imbalance needs to be corrected before quadriceps exercises are started. The non-operative rehabilitation protocol should be divided into different phases based on the patient's progress. The goal of the first phase is to reduce pain and swelling, improve the balance between vastus medialis and vastus lateralis, restore normal gait, and decrease loading of the patello-femoral joint. The second phase should include improvement of postural control and coordination of the lower extremity, increase of quadriceps strength and when needed hip muscle strength, and restore good knee function. The patient should be encouraged to return to or to start with a suitable regular physical exercise. Therefore, the third phase should include functional exercises. Towards the end of the treatment, single-leg functional tests and functional knee scores should be used for evaluating clinical outcome. A non-operative treatment of patients with anterior knee pain should be tried for at least 3 months before considering other treatment options. PMID:24997734

Werner, Suzanne

2014-10-01

323

Chronic tendinopathy: effectiveness of eccentric exercise  

PubMed Central

Objectives: To determine the effectiveness of eccentric exercise (EE) programmes in the treatment of common tendinopathies. Data sources: Relevant randomised controlled trials (RCTs) were sourced using the OVID website databases: MEDLINE (1966–Jan 2006), CINAHL (1982–Jan 2006), AMED (1985–Jan 2006), EMBASE (1988–Jan 2006), and all EBM reviews – Cochrane DSR, ACP Journal Club, DARE, and CCTR (Jan 2006). The Physiotherapy Evidence Database (PEDro) was also searched using the keyword: eccentric. Review methods: The PEDro and van Tulder scales were employed to assess methodological quality. Levels of evidence were then obtained according to predefined thresholds: Strong–consistent findings among multiple high?quality RCTs. Moderate–consistent findings among multiple low?quality RCTs and/or clinically controlled trials (CCTs) and/or one high?quality RCT. Limited–one low?quality RCT and/or CCT. Conflicting–inconsistent findings among multiple trials (RCTs and/or CCTs). No evidence–no RCTs or CCTs. Results: Twenty relevant studies were sourced, 11 of which met the inclusion criteria. These included studies of Achilles tendinopathy (AT), patella tendinopathy (PT) and tendinopathy of the common wrist extensor tendon of the lateral elbow (LET). Limited levels of evidence exist to suggest that EE has a positive effect on clinical outcomes such as pain, function and patient satisfaction/return to work when compared to various control interventions such as concentric exercise (CE), stretching, splinting, frictions and ultrasound. Levels of evidence were found to be variable across the tendinopathies investigated. Conclusions: This review demonstrates the dearth of high?quality research in support of the clinical effectiveness of EE over other treatments in the management of tendinopathies. Further adequately powered studies that include appropriate randomisation procedures, standardised outcome measures and long?term follow?up are required. PMID:17062655

Woodley, Brett L; Newsham?West, Richard J; Baxter, G David

2007-01-01

324

Osteotomy at the distal third of tibial tuberosity with LCP L-buttress plate for correction of tibia vara  

PubMed Central

Background Many osteotomy methods and fixation types have been used to correct the misalignment observed in tibia vara and to achieve a more uniform distribution of weight across the knee joint. Purpose The aim of this study is to test the efficacy and safety of a modified closing wedge high tibial osteotomy (CWHTO) procedure for tibia vara. Methods In this prospective study, young adults with tibia vara and mild medial arthritic changes were included. A CWHTO was performed at the distal third of the tibial tuberosity, instead of the conventional proximal site. An L-shaped locking compression plate was used for internal fixation. Before/after evaluation of femoro-tibial angle (FTA), pain relief, patellar height, and posterior tibial slope were evaluated. Adverse events were monitored. Results Seventy-five knees from 46 patients aged 27.2?±?5.8 years (range, 14–43 years) underwent the modified CWHTO procedure. After a follow-up of 26.3?±?7.4 months (range, 15–46 months), FTA correction was 12.4°?±?4.7° (range, 7°–31°), and pain was relieved. Reduction in the posterior tibial slope was 3.0°?±?2.3° (p?patella height. Bone union was observed in all patients. There were a delayed union in four knees, a peroneal nerve lesion in five knees causing partial paralysis and/or sensory loss, and infections in two knees. Three patients underwent a second surgery. All adverse events were successfully treated except for a case of extensor hallucis longus muscle paralysis. Conclusions The modified CWHTO procedure is efficient and safe for the correction of tibia vara in young patients. PMID:24521174

2014-01-01

325

Coordinative variability and overuse injury  

PubMed Central

Overuse injuries are generally defined as a repetitive micro-trauma to tissue. Many researchers have associated particular biomechanical parameters as an indicator of such injuries. However, while these parameters have been reported in single studies, in many instances, it has been difficult to verify these parameters as causative to the injury. We have investigated overuse injuries, such as patella-femoral pain syndrome, using a dynamical systems approach. Using such methods, the importance of the structure of coordinative variability (i.e. the variability of the interaction between segments or joints) becomes apparent. We view coordinative variability as functionally important to the movement and different from end-point or goal variability. Using concepts derived from the work of Bernstein, we conducted studies using a continuous relative phase and/or modified vector coding approaches to investigate the coordinative variability of overuse injuries. Consistently, we have found that the higher variability state of a coordinative structure is the healthy state while the lower variability state is the unhealthy or pathological state. It is clear that very high coordinative variability could also result in injury and that there must be a window of ‘higher variability’ in which non-injured athletes function. While this finding that coordinative variability is functional has been shown in several studies, it is still not clear if reduced variability contributes to or results from the injury. Studies are currently underway to determine the potential reasons for the reduced variability in injured athletes. Nevertheless, our laboratory believes that this understanding of how joints interact can be important in understanding overuse injuries. PMID:23186012

2012-01-01

326

The vastus lateralis muscle: an anatomical investigation.  

PubMed

Anterior knee pain or patellofemoral pain syndrome is commonly encountered by clinicians, but the pathogenesis of this condition is not well understood. While much research has centred around the relationship between vastus medialis and anterior knee pain, little is known about the most lateral of the quadriceps muscle group, vastus lateralis (VL). Knowledge of the anatomical organization of VL is not only necessary to understand its precise function, but to also assist in the development of clinical and biomechanical models of knee dysfunction. The purpose of this study was to investigate the detailed morphology of VL, specifically to provide data relating to architecture, attachment sites, innervation, and the presence of anatomical partitioning within the muscle. The VL muscle was examined in 10 cadaveric lower limbs using macrodissection techniques. On the basis of architecture and innervation, this muscle comprised four partitions with each receiving its own unique nerve branch. The mean fascicular length of VL was 7 cm and the mean fascicular and muscle physiological cross-sectional areas were 1.2 cm(2) and 21.6 cm(2), respectively. In addition to inserting proximally at the base of the greater trochanter and distally into the superolateral border and base of the patella, three additional attachment sites were identified: the lateral intermuscular septum, iliotibial band, and the rectus tendon. The results of this study suggest that the gross morphology of VL is more complex than previously described, and the information provided regarding architecture will contribute to knowledge regarding the function of VL as well as its role in knee joint dysfunction. PMID:20309954

Becker, I; Baxter, G D; Woodley, S J

2010-07-01

327

Cumulative Lead Exposure and Age at Menopause in the Nurses’ Health Study Cohort  

PubMed Central

Background: Early menopause has been associated with many adverse health outcomes, including increased risk of cardiovascular disease morbidity and mortality. Lead has been found to be adversely associated with female reproductive function, but whether exposures experienced by the general population are associated with altered age at menopause has not been explored. Objective: Our goal was to assess the association between cumulative lead exposure and age at natural menopause. Methods: Self-reported menopausal status and bone lead concentration measured with K-shell X-ray fluorescence—a biomarker of cumulative lead exposure—were obtained from 434 women participants in the Nurses’ Health Study. Results: The mean (± SD) age at natural menopause was 50.8 ± 3.6 years. Higher tibia lead level was associated with younger age at menopause. In adjusted analyses, the average age of menopause for women in the highest tertile of tibia lead was 1.21 years younger (95% CI: –2.08, –0.35) than for women in the lowest tertile (p-trend = 0.006). Although the number of cases was small (n = 23), the odds ratio for early menopause (< 45 years of age) was 5.30 (95% CI: 1.42, 19.78) for women in the highest tertile of tibia lead compared with those in the lowest tertile (p-trend = 0.006). There was no association between patella or blood lead and age at menopause. Conclusions: Our results support an association between low-level cumulative lead exposure and an earlier age at menopause. These data suggest that low-level lead exposure may contribute to menopause-related health outcomes in older women through effects on age at menopause. Citation: Eum KD, Weisskopf MG, Nie LH, Hu H, Korrick SA. 2014. Cumulative lead exposure and age at menopause in the Nurses’ Health Study Cohort. Environ Health Perspect 122:229–234;?http://dx.doi.org/10.1289/ehp.1206399 PMID:24398113

Eum, Ki-Do; Nie, Linda H.; Hu, Howard; Korrick, Susan A.

2014-01-01

328

Changes in knee cartilage T2 values over 24 months in subjects with and without risk factors for knee osteoarthritis and their association with focal knee lesions at baseline - data from the Osteoarthritis Initiative  

PubMed Central

Purpose To examine the changes in knee cartilage T2 values over 24 months in subjects with and without risk factors for knee osteoarthritis (OA) and their association with focal knee lesions at baseline. Materials and Methods Forty-one subjects without, and 101 subjects with OA risk factors (such as history of knee injury or surgery) were selected from the Osteoarthritis Initiative database (age: 45-55 years, no radiographic OA in the right knee). Baseline MR images of the right knee were assessed for prevalence and grade of focal knee lesions. Right knee cartilage T2 measurements were performed in five compartments (patella, medial/lateral femur/tibia) at baseline and 24 month follow-up. Results Compared to subjects without OA risk factors, those with OA risk factors showed no significant differences in baseline prevalence and grade of focal knee lesions (p>0.05), but had significantly higher T2 values in the medial femur compartment at both time points (p<0.05). T2 values averaged over all five compartments increased significantly over 24 months in both groups, but differences in T2 increase between the groups were not significant. Subjects with cartilage lesions showed significantly higher T2 values compared to subjects without cartilage lesions at both time points, but no accelerated T2 increase over 24 months (p>0.05). Conclusion Cartilage T2 values significantly increased over 24 months in subjects with and without OA risk factors, but neither the presence of OA risk factors nor the presence of cartilage lesions at baseline were associated with these T2 increases. PMID:21987496

Baum, Thomas; Stehling, Christoph; Joseph, Gabby B.; Carballido-Gamio, Julio; Schwaiger, Benedikt J.; Müller-Höcker, Christina; Nevitt, Michael C.; Lynch, John; McCulloch, Charles E.; Link, Thomas M.

2011-01-01

329

Monitoring of muscle and bone recovery in spinal cord injury patients treated with electrical stimulation using three-dimensional imaging and segmentation techniques: methodological assessment.  

PubMed

Muscle tissue composition accounting for the relative content of muscle fibers and intramuscular adipose and loose fibrous tissues can be efficiently analyzed and quantified using images from spiral computed tomography (S-CT) technology and the associated distribution of Hounsfield unit (HU) values. Muscle density distribution, especially when including the whole muscle volume, provides remarkable information on the muscle condition. Different physiological and pathological scenarios can be depicted using the muscle characterization technique based on the HU values and the definition of appropriate intervals and the association of such intervals to different colors. Using this method atrophy, degeneration, and restoration in denervated muscle undergoing electrical stimulation treatments can be clearly displayed and monitored. Moreover, finite element methods are employed to calculate Young's modulus on the patella bone and to analyze correlation between muscle contraction and bone strength changes. The reliability of this tool though depends on S-CT assessment and calibration. To assess imaging quality and the use of HU values to display muscle composition, different S-CT devices are compared using a Quasar body scanner. Density distributions and volumes of various calibration elements such as lung, polyethylene, water equivalent, and trabecular and dense bone are measured with different scanning protocols and at different points of time. The results show that every scanned element undergoes HU variations, which are greater for materials at the extremes of the HU scale, such as dense bone and lung inhale. Moreover, S-CT scanning with low tube voltages (80 KV) produces inaccurate HU values especially in bones. In conclusion, 3-D modeling techniques based on S-CT scanning is a powerful follow-up tool that may provide structural information at the millimeter scale, and thus may drive choice and timing to validate rehabilitation protocols. PMID:21401674

Gargiulo, Paolo; Helgason, Thordur; Reynisson, Páll Jens; Helgason, Benedikt; Kern, Helmut; Mayr, Winfried; Ingvarsson, Páll; Carraro, Ugo

2011-03-01

330

Disease associated balanced chromosome rearrangements: a resource for large scale genotype-phenotype delineation in man  

PubMed Central

Disease associated balanced chromosomal rearrangements (DBCRs), which truncate, delete, or otherwise inactivate specific genes, have been instrumental for positional cloning of many disease genes. A network of cytogenetic laboratories, Mendelian Cytogenetics Network (MCN), has been established to facilitate the identification and mapping of DBCRs. To get an estimate of the potential of this approach, we surveyed all cytogenetic archives in Denmark and southern Sweden, with a population of ~6.6 million. The nine laboratories have performed 71 739 postnatal cytogenetic tests. Excluding Robertsonian translocations and chromosome 9 inversions, we identified 216 DBCRs (~0.3%), including a minimum estimate of 114 de novo reciprocal translocations (0.16%) and eight de novo inversions (0.01%). Altogether, this is six times more frequent than in the general population, suggesting a causal relationship with the traits involved in most of these cases. Of the identified cases, only 25 (12%) have been published, including 12 cases with known syndromes and 13 cases with unspecified mental retardation/congenital malformations. The remaining DBCRs were associated with a plethora of traits including mental retardation, dysmorphic features, major congenital malformations, autism, and male and female infertility. Several of the unpublished DBCRs defined candidate breakpoints for nail-patella, Prader-Willi, and Schmidt syndromes, ataxia, and ulna aplasia. The implication of the survey is apparent when compared with MCN; altogether, the 292 participating laboratories have performed >2.5 million postnatal analyses, with an estimated ~7500 DBCRs stored in their archives, of which more than half might be causative mutations. In addition, an estimated 450-500 novel cases should be detected each year. Our data illustrate that DBCRs and MCN are resources for large scale establishment of phenotype-genotype relationships in man.???Keywords: translocations; inversions; abnormal phenotypes; frequency PMID:11073540

Bugge, M.; Bruun-Petersen, G.; Brondum-Nielsen, K.; Friedrich, U.; Hansen, J.; Jensen, G.; Jensen, P.; Kristoffersson, U.; Lundsteen, C.; Niebuhr, E.; Rasmussen, K.; Rasmussen, K.; Tommerup, N.

2000-01-01

331

Lower extremity finite element model for crash simulation  

SciTech Connect

A lower extremity model has been developed to study occupant injury mechanisms of the major bones and ligamentous soft tissues resulting from vehicle collisions. The model is based on anatomically correct digitized bone surfaces of the pelvis, femur, patella and the tibia. Many muscles, tendons and ligaments were incrementally added to the basic bone model. We have simulated two types of occupant loading that occur in a crash environment using a non-linear large deformation finite element code. The modeling approach assumed that the leg was passive during its response to the excitation, that is, no active muscular contraction and therefore no active change in limb stiffness. The approach recognized that the most important contributions of the muscles to the lower extremity response are their ability to define and modify the impedance of the limb. When nonlinear material behavior in a component of the leg model was deemed important to response, a nonlinear constitutive model was incorporated. The accuracy of these assumptions can be verified only through a review of analysis results and careful comparison with test data. As currently defined, the model meets the objective for which it was created. Much work remains to be done, both from modeling and analysis perspectives, before the model can be considered complete. The model implements a modeling philosophy that can accurately capture both kinematic and kinetic response of the lower limb. We have demonstrated that the lower extremity model is a valuable tool for understanding the injury processes and mechanisms. We are now in a position to extend the computer simulation to investigate the clinical fracture patterns observed in actual crashes. Additional experience with this model will enable us to make a statement on what measures are needed to significantly reduce lower extremity injuries in vehicle crashes. 6 refs.

Schauer, D.A.; Perfect, S.A.

1996-03-01

332

Antifouling and toxic properties of the bioactive metabolites from the seagrasses Syringodium isoetifolium and Cymodocea serrulata.  

PubMed

The present study documents the antifouling and toxic properties of seagrasses Syringodium isoetifolium and Cymodocea serrulata. For that, the seagrasses S. isoetifolium and C. serrulata were extracted individually using organic solvents viz. dichloromethane, acetone and methanol. Amongst the extracts, the maximum antimicrofouling and antimacrofouling activities were exhibited by methanol extracts of both the seagrasses. The Minimal Inhibitory Concentration (MIC) of methanolic extracts of seagrasses was ranged from 1.0 to 10µg/ml against test biofilm bacteria and microalgal strains. Similarly, 100% fouling inhibition of limpet Patella vulgata was found at 6.0mg/ml of methanolic extracts of seagrasses. The mussel Perna indica showed 50% of byssal production and attachment inhibition at 21.51±2.03, 17.82±1.07µg/ml and the anticrustaecean activity for 50% mortality of Artemia salina was recorded at 732.14±9.21 and 394.16±5.16µg/ml respectively for methanolic extracts of S. isoetifolium and C. serrulata. The minimal inhibitory and higher lethal concentrations of active methanol extracts shows it?s less toxic nature. Based on the prolific results, methanol extracts of S. isoetifolium and C. serrulata were subjected to purification using silica gel column and thin layer chromatography. Then the active compounds of the bioassay guided fractions were partially characterized using gas chromatography coupled with mass spectroscopy (GC-MS) and keyed out that fatty acids (C16 to C24) were the major components which responsible for the antifouling properties of the candidate seagrasses. PMID:24576890

Iyapparaj, Palanisamy; Revathi, Peranandam; Ramasubburayan, Ramasamy; Prakash, Santhiyagu; Palavesam, Arunachalam; Immanuel, Grasian; Anantharaman, Perumal; Sautreau, Asmita; Hellio, Claire

2014-05-01

333

High Body Mass Index is Associated with Increased Diurnal Strains in the Articular Cartilage of the Knee  

PubMed Central

Objective Obesity is an important risk factor for osteoarthritis and is associated with changes in both the biomechanical and inflammatory environments within the joint. However, the relationship between obesity and cartilage deformation is not fully understood. The goal of this study was to determine the effects of body mass index (BMI) on the magnitude of diurnal cartilage strain in the knee. Methods Three-dimensional maps of knee cartilage thickness were developed from 3T magnetic resonance images of asymptomatic age- and sex-matched subjects with normal (18.5–24.9 kg/m2) or high (25–31 kg/m2) BMI. Site-specific magnitudes of diurnal cartilage strain were determined using aligned images recorded at 8:00 AM and 4:00 PM on the same day. Results High BMI individuals had significantly thicker cartilage on the patella and femoral groove than the normal BMI individuals. Diurnal cartilage strains were dependent on location as well as BMI. Subjects with high BMI exhibited significantly higher compressive strain in tibial cartilage than did those with normal BMI. Cartilage thickness decreased significantly on both femoral condyles from the AM to PM time point; however, there was no significant effect of BMI on diurnal cartilage strain in the femur. Conclusions Increased BMI is associated with increased diurnal strains in the articular cartilage of both the medial and lateral compartments of the knee. The increased cartilage strains measured in high BMI individuals may, in part, explain the elevated OA risk associated with obesity or may reflect altered cartilage mechanical properties in subjects with high BMI. PMID:23818303

Widmyer, Margaret R.; Utturkar, Gangadhar M.; Leddy, Holly A.; Coleman, Jeremy L.; Spritzer, Charles E.; Moorman, CT; DeFrate, Louis E.; Guilak, Farshid

2014-01-01

334

An ultrastructural study of connective tissue in mollusc integument: II. Gastropoda.  

PubMed

We studied the ultrastructure of the subepidermal connective tissue (SEC) in different zones of the integument in terrestrial, marine and freshwater gastropods (eight species). In all cases, the SEC was a layer of loose connective tissue between the basal membrane (BM) of the epidermis and the connective tissue of the deeper muscle layers. It was of monotonous structure and not differentiated into layers such as are found in mammalian dermis. The extracellular matrix (ECM) consisted of a network of collagen fibrils of variable diameter, with abundant anchoring devices and proteoglycans. In six species, variables quantities of haemocyanin were present within haemocoelic sinuses present in the SEC. The thickness and density of the BM varied from species to species, as well as within species in the various zones of integument. The ultrastructure of the lamina densa (LD) was indistinguishable from that of BM in bivalves and similar to that in mammals, although basotubules and double pegs were absent. An irregularly spaced lamina lucida was usually present and was often shot thorough with filaments and small protrusions of the LD that connected with epithelial plasma membrane or with hemidesmosomes. A lamina fibroreticularis was not present. LD protrusions characterize the connection between BM and the ECM of SEC. In the terrestrial gastropods, a spongy matrix with ultrastructure closely similar to LD occupied large tracts of the SEC. In the mantle region of Arion rufus, the integumental SEC contained large cavities filled with spherical concretions, probably representing rudiments of a shell. In the mantle where the integument contained abundant muscle fibres, the BM was thick and directly connected to the ECM of the SEC which consisted of compact laminae of collagen fibrils with abundant anchoring devices. Along the edge of the foot of Patella ulyssiponensis, the SEC contained a layer of paramyosinic muscle fibres adhering to the epidermis. No differences or gradations in integumental SEC structure could be related to the phylogenetic position of the species examined. PMID:11949779

Bairati, A; Comazzi, M; Gioria, M

2001-10-01

335

Conorfamide-Sr2, a gamma-carboxyglutamate-containing FMRFamide-related peptide from the venom of Conus spurius with activity in mice and mollusks  

PubMed Central

A novel peptide, conorfamide-Sr2 (CNF-Sr2), was purified from the venom extract of Conus spurius, collected in the Caribbean Sea off the Yucatan Peninsula. Its primary structure was determined by automated Edman degradation and amino acid analysis, and confirmed by electrospray ionization mass spectrometry. Conorfamide-Sr2 contains 12 amino acids and no Cys residues, and it is only the second FMRFamide-related peptide isolated from a venom. Its primary structure GPM?DPL?IIRI-nh2, (?, gamma-carboxyglutamate;-nh2, amidated C-terminus; calculated monoisotopic mass, 1,468.72 Da; experimental monoisotopic mass, 1,468.70 Da) shows two features that are unusual among FMRFamide-related peptides (FaRPs, also known as RFamide peptides), namely the novel presence of gamma-carboxyglutamate, and a rather uncommon C-terminal residue, Ile. CNF-Sr2 exhibits paralytic activity in the limpet Patella opea and causes hyperactivity in the freshwater snail Pomacea paludosa and in the mouse. The sequence similarities of CNF-Sr2 with FaRPs from marine and freshwater mollusks and mice might explain its biological effects in these organisms. It also resembles FaRPs from polychaetes (the prey of C. spurius), which suggests a natural biological role. Based on these similarities, CNF-Sr2 might interact with receptors of these three distinct types of FaRPs, G-protein-coupled receptors, Na+ channels activated by FMRFamide (FaNaCs), and acid-sensing ion channels (ASICs). The biological activities of CNF-Sr2 in mollusks and mice make it a potential tool to study molecular targets in these and other organisms. PMID:18201803

Aguilar, Manuel B.; Luna-Ramírez, Karen S.; Echeverría, Daniel; Falcón, Andrés; Olivera, Baldomero M.; Heimer de la Cotera, Edgar P.; Maillo, María

2008-01-01

336

Simultaneous 3D segmentation of three bone compartments on high resolution knee MR images from osteoarthritis initiative (OAI) using graph cuts  

NASA Astrophysics Data System (ADS)

Osteoarthritis (OA) is associated with degradation of cartilage and related changes in the underlying bone. Quantitative measurement of those changes from MR images is an important biomarker to study the progression of OA and it requires a reliable segmentation of knee bone and cartilage. As the most popular method, manual segmentation of knee joint structures by boundary delineation is highly laborious and subject to user-variation. To overcome these difficulties, we have developed a semi-automated method for segmentation of knee bones, which consisted of two steps: placement of seeds and computation of segmentation. In the first step, seeds were placed by the user on a number of slices and then were propagated automatically to neighboring images. The seed placement could be performed on any of sagittal, coronal, and axial planes. The second step, computation of segmentation, was based on a graph-cuts algorithm where the optimal segmentation is the one that minimizes a cost function, which integrated the seeds specified by the user and both the regional and boundary properties of the regions to be segmented. The algorithm also allows simultaneous segmentation of three compartments of the knee bone (femur, tibia, patella). Our method was tested on the knee MR images of six subjects from the osteoarthritis initiative (OAI). The segmentation processing time (mean+/-SD) was (22+/-4)min, which is much shorter than that by the manual boundary delineation method (typically several hours). With this improved efficiency, our segmentation method will facilitate the quantitative morphologic analysis of changes in knee bones associated with osteoarthritis.

Shim, Hackjoon; Kwoh, C. Kent; Yun, Il Dong; Lee, Sang Uk; Bae, Kyongtae

2009-02-01

337

Pattern of anterior cruciate ligament force in normal walking.  

PubMed

The goal of this study was to calculate and explain the pattern of anterior cruciate ligament (ACL) loading during normal level walking. Knee-ligament forces were obtained by a two-step procedure. First, a three-dimensional (3D) model of the whole body was used together with dynamic optimization theory to calculate body-segmental motions, ground reaction forces, and leg-muscle forces for one cycle of gait. Joint angles, ground reaction forces, and muscle forces obtained from the gait simulation were then input into a musculoskeletal model of the lower limb that incorporated a 3D model of the knee. The relative positions of the femur, tibia, and patella and the forces induced in the knee ligaments were found by solving a static equilibrium problem at each instant during the simulated gait cycle. The model simulation predicted that the ACL bears load throughout stance. Peak force in the ACL (303 N) occurred at the beginning of single-leg stance (i.e., contralateral toe off). The pattern of ACL force was explained by the shear forces acting at the knee. The balance of muscle forces, ground reaction forces, and joint contact forces applied to the leg determined the magnitude and direction of the total shear force acting at the knee. The ACL was loaded whenever the total shear force pointed anteriorly. In early stance, the anterior shear force from the patellar tendon dominated the total shear force applied to the leg, and so maximum force was transmitted to the ACL at this time. ACL force was small in late stance because the anterior shear forces supplied by the patellar tendon, gastrocnemius, and tibiofemoral contact were nearly balanced by the posterior component of the ground reaction. PMID:15111067

Shelburne, Kevin B; Pandy, Marcus G; Anderson, Frank C; Torry, Michael R

2004-06-01

338

Simultaneous prediction of muscle and contact forces in the knee during gait.  

PubMed

Musculoskeletal models are currently the primary means for estimating in vivo muscle and contact forces in the knee during gait. These models typically couple a dynamic skeletal model with individual muscle models but rarely include articular contact models due to their high computational cost. This study evaluates a novel method for predicting muscle and contact forces simultaneously in the knee during gait. The method utilizes a 12 degree-of-freedom knee model (femur, tibia, and patella) combining muscle, articular contact, and dynamic skeletal models. Eight static optimization problems were formulated using two cost functions (one based on muscle activations and one based on contact forces) and four constraints sets (each composed of different combinations of inverse dynamic loads). The estimated muscle and contact forces were evaluated using in vivo tibial contact force data collected from a patient with a force-measuring knee implant. When the eight optimization problems were solved with added constraints to match the in vivo contact force measurements, root-mean-square errors in predicted contact forces were less than 10 N. Furthermore, muscle and patellar contact forces predicted by the two cost functions became more similar as more inverse dynamic loads were used as constraints. When the contact force constraints were removed, estimated medial contact forces were similar and lateral contact forces lower in magnitude compared to measured contact forces, with estimated muscle forces being sensitive and estimated patellar contact forces relatively insensitive to the choice of cost function and constraint set. These results suggest that optimization problem formulation coupled with knee model complexity can significantly affect predicted muscle and contact forces in the knee during gait. Further research using a complete lower limb model is needed to assess the importance of this finding to the muscle and contact force estimation process. PMID:19962703

Lin, Yi-Chung; Walter, Jonathan P; Banks, Scott A; Pandy, Marcus G; Fregly, Benjamin J

2010-03-22

339

Inducement of semitendinosus tendon regeneration to the pes anserinus after its harvest for anterior cruciate ligament reconstruction-A new inducer grafting technique  

PubMed Central

Purpose To investigate the usefulness of the “inducer grafting” technique for regeneration of the semitendinosus (ST) tendon after its harvest for anterior cruciate ligament (ACL) reconstruction. Methods Twenty knees of 20 patients (mean age at the time of surgery, 23.1?years) underwent ACL reconstruction with a double bundle autograft using the ST tendon (7 patients) and the ST + the gracilis (G) tendons (13 patients). “Inducer grafting” technique After harvesting the ST tendon, a passing pin with a loop thread is inserted along with the tendon stripper. The passing pin is pulled out from the medial thigh and the loop thread retained. As an inducer graft, the ST tendon branch is used. After the ACL graft has been secured, the inducer graft is sutured to the pes anserinus and the proximal end passed through by pulling the thread out. Then the inducer graft is placed within the tendon canal. The mean follow-up period was 15?months. The presence and morphology of the regenerated ST tendon were examined by MRI. And the isometric hamstring strength was examined at 45°, 90° and 120° of knee flexion. Results One month after the operation in all the patients, MRI demonstrated a low-intensity structure at the anatomical location of the ST, at the level of the superior pole of the patella and the joint line, apparently representing the regenerated ST tendon. Four months after the operation, the distal portion of the regenerated ST tendon had reached the pes anserinus in all patients. Twelve months after the operation, the regenerated ST tendon was hypertrophic in 19 of the 20 patients (95%). The isometric knee flexion torque of the ACL-reconstructed limb was significantly lower at 90° and 120° compared with the contralateral limb. Conclusion These results suggest that the “inducer grafting” technique is able to improve the regeneration rate of the harvested ST tendon and promote hypertrophy of the regenerated ST tendon, extending all the way to the pes anserinus. However, this technique couldn’t improve the deficits in knee flexion torque after ACL reconstruction. PMID:22607724

2012-01-01

340

The TOPSHOCK study: Effectiveness of radial shockwave therapy compared to focused shockwave therapy for treating patellar tendinopath - design of a randomised controlled trial  

PubMed Central

Background Patellar tendinopathy is a chronic overuse injury of the patellar tendon that is especially prevalent in people who are involved in jumping activities. Extracorporeal Shockwave Therapy is a relatively new treatment modality for tendinopathies. It seems to be a safe and promising part of the rehabilitation program for patellar tendinopathy. Extracorporeal Shockwave Therapy originally used focused shockwaves. Several years ago a new kind of shockwave therapy was introduced: radial shockwave therapy. Studies that investigate the effectiveness of radial shockwave therapy as treatment for patellar tendinopathy are scarce. Therefore the aim of this study is to compare the effectiveness of focussed shockwave therapy and radial shockwave therapy as treatments for patellar tendinopathy. Methods/design The TOPSHOCK study (Tendinopathy Of Patella SHOCKwave) is a two-armed randomised controlled trial in which the effectiveness of focussed shockwave therapy and radial shockwave therapy are directly compared. Outcome assessors and patients are blinded as to which treatment is given. Patients undergo three sessions of either focused shockwave therapy or radial shockwave therapy at 1-week intervals, both in combination with eccentric decline squat training. Follow-up measurements are scheduled just before treatments 2 and 3, and 1, 4, 7 and 12 weeks after the final treatment. The main outcome measure is the Dutch VISA-P questionnaire, which asks for pain, function and sports participation in subjects with patellar tendinopathy. Secondary outcome measures are pain determined with a VAS during ADL, sports and decline squats, rating of subjective improvement and overall satisfaction with the treatment. Patients will also record their sports activities, pain during and after these activities, and concurrent medical treatment on a weekly basis in a web-based diary. Results will be analysed according to the intention-to-treat principle. Discussion The TOPSHOCK study is the first randomised controlled trial that directly compares the effectiveness of focused shockwave therapy and radial shockwave therapy, both in combination with eccentric decline squat training, for treating patellar tendinopathy. Trial registration Trial registration number NTR2774. PMID:21989041

2011-01-01

341

Principles of brain plasticity in improving sensorimotor function of the knee and leg in patients with anterior cruciate ligament injury: a double-blind randomized exploratory trial  

PubMed Central

Background Severe traumatic knee injury, including injury to the anterior cruciate ligament (ACL), leads to impaired sensorimotor function. Although improvements are achieved by training, impairment often persists. Because good sensorimotor function is associated with better patient-reported function and a potential lower risk of future joint problems, more effective treatment is warranted. Temporary cutaneous anesthesia of adjacent body parts was successfully used on the hand and foot to improve sensorimotor function. The aim of this study was to test whether this principle of brain plasticity could be used on the knee. The hypothesis was that temporary anesthesia of the skin area above and below the knee would improve sensorimotor function of the ipsilateral knee and leg in subjects with ACL injury. Methods In this double-blind exploratory study, 39 subjects with ACL injury (mean age 24?years, SD 5.2, 49% women, mean 52?weeks after injury or reconstruction) and self-reported functional limitations and lack of trust in the knee were randomized to temporary local cutaneous application of anesthetic (EMLA®) (n?=?20) or placebo cream (n?=?19). Fifty grams of EMLA®, or placebo, was applied on the leg 10?cm above and 10?cm below the center of patella, leaving the area around the knee without cream. Measures of sensory function (perception of touch, vibration sense, knee kinesthesia) and motor function (knee muscle strength, hop test) were assessed before and after 90 minutes of treatment with EMLA® or placebo. The paired t-test was used for comparisons within groups and analysis of variance between groups, except for ordinal data where the Wilcoxon signed rank test, or Mann–Whitney test, was used. The number of subjects needed was determined by an a priori sample size calculation. Results No statistically significant or clinically relevant differences were seen over time (before vs. after) in the measures of sensory or motor functions in the EMLA® group or in the placebo group. There were no differences between the groups due to treatment effect (EMLA® vs. placebo). Conclusions Temporary cutaneous anesthesia of adjacent body parts had no effect in improving sensorimotor function of the knee and leg in subjects with severe traumatic knee ligament injury. PMID:22574814

2012-01-01

342

Symptomatic knee disorders in floor layers and graphic designers. A cross-sectional study  

PubMed Central

Background Previous studies have described an increased risk of developing tibio-femoral osteoarthritis (TF OA), meniscal tears and bursitis among those with a trade as floor layers. The purpose of this study was to analyse symptomatic knee disorders among floor layers that were highly exposed to kneeling work tasks compared to graphic designers without knee-demanding work tasks. Methods Data on the Knee injury and Osteoarthritis Outcome Score (KOOS) were collected by questionnaires. In total 134 floor layers and 120 graphic designers had a bilateral radiographic knee examination to detect TF OA and patella-femoral (PF) OA. A random sample of 92 floor layers and 49 graphic designers had Magnetic Resonance Imaging (MRI) of both knees to examine meniscal tears. Means of the subscales of KOOS were compared by analysis of variance. The risk ratio of symptomatic knee disorders defined as a combination of radiological detected knee OA or MRI-detected meniscal tears combined with a low KOOS score was estimated by logistic regression in floor layers with 95% confidence interval (CI) and adjusted for age, body mass index, traumas, and knee-straining sports activities. Symptomatic knee OA or meniscal tears were defined as a combination of low KOOS-scores and radiographic or MRI pathology. Results Symptomatic TF and medial meniscal tears were found in floor layers compared to graphic designers with odds ratios 2.6 (95%CI 0.99-6.9) and 2.04 (95% CI 0.77-5.5), respectively. There were no differences in PF OA. Floor layers scored significantly lower on all KOOS subscales compared to graphic designers. Significantly lower scores on the KOOS subscales were also found for radiographic TF and PF OA regardless of trade but not for meniscal tears. Conclusions The study showed an overall increased risk of developing symptomatic TF OA in a group of floor layers with a substantial amount of kneeling work positions. Prevention would be appropriate to reduce the proportion of kneeling postures e.g. by working with tools used from a standing working position. PMID:23009280

2012-01-01

343

The cell lineage of the polyplacophoran, Chaetopleura apiculata: variation in the spiralian program and implications for molluscan evolution.  

PubMed

Polyplacophorans, or chitons, are an important group of molluscs, which are argued to have retained many plesiomorphic features of the molluscan body plan. Polyplacophoran trochophore larvae posses several features that are distinctly different from those of their sister trochozoan taxa, including modifications of the ciliated prototrochal cells, the postrochal position of the larval eyes or ocelli, epidermal calcareous spicules, and a collection of serially reiterated epidermal shell plates. Despite these differences, chitons demonstrate a canonical pattern of equal spiral cleavage shared by other spiralian phyla that permits the identification of homologous cells across this animal clade. Cell lineage analysis using intracellular labeling on one chiton species, Chaetopleura apiculata, shows that the ocelli are generated from different lineal precursors (second-quartet micromeres: 2a, 2c) compared to those in all other spiralians studied to date (first-quartet micromeres: 1a, 1c). This situation implies that significant changes have also occurred in terms of the inductive interactions that control eye development in the spiralians. Although radical departures from the spiralian developmental program are seen in some molluscs (i.e., cephalopods), the findings presented here indicate that important changes can occur even within the highly constrained framework of the spiral cleavage program. Among spiralians, variation has been reported for the origin of the anterior, sensory, apical organ, which arises from the 1c and 1d micromeres in C. apiculata. The prototroch of C. apiculata consists of two to three irregular rows of ciliated cells but arise from 1q and 2q daughters, similar to that of Ischnochiton rissoi, as well as the gastropod, Patella vulgata. Despite certain early claims, there is no supporting evidence that any of the shell plates arise pretrochally in C. apiculata. The first seven of eight definitive shell plates that arise in the larva originate from shell secreting grooves in the postrochal region (derived from 2c, 2d, 3d). Earlier descriptions indicate that the eighth plate arises later at metamorphosis, and as this is formed posteriorly, it too forms in the postrochal region. On the other hand, epidermal spicules originate from both pretrochal and postrochal cells (1a,1d, 2a, 2c, 3c, 3d). The significance of these observations is discussed in light of various hypotheses concerning the origin of the conchiferan shell. This study reveals conservation, as well as evolutionary novelty, in the assignment of specific cell fates in the spiralians. PMID:15242797

Henry, Jonathan Q; Okusu, Akiko; Martindale, Mark Q

2004-08-01

344

Evaluation of the uncertainties associated with in vivo X-ray fluorescence bone lead calibrations  

NASA Astrophysics Data System (ADS)

An anthropometric leg phantom developed at the University of Cincinnati (UC) was used to evaluate the effects that changes in leg position and variation between subjects has on in vivo x-ray fluorescence (XRF) measurements of stable lead in bone. The changes in leg position that were evaluated include changes in source-phantom distance ranging between 0.0 mm and 30.0 mm and phantom rotation over 40 degrees. Source-phantom distance was determined to have a significant effect on XRF measurement results particularly at source-phantom distances greater than 10.0 mm. Rotation of the leg phantom through 40 degrees was determined to have no significant effect on XRF measurement results. Between subject factors that were evaluated include bone calcium content and overlying tissue thickness. Bone calcium content was determined to have a significant effect on XRF measurements when measuring lead in micrograms per gram bone material. However, if measurement results of micrograms of lead per gram calcium (or per gram bone mineral) is used the normalization method makes the change in calcium content not significant. Overlying tissue thickness was determined to have no significant effect on XRF measurement results with tissue thickness ranging between 5.7 and 11.62 mm. The UC leg phantom was modified to include a fibula bone phantom so that the effect that the fibula has on XRF measurement results could be evaluated. The fibula was determined to have no significant effect on XRF measurement results and in the future need not be incorporated into in vivo XRF calibration phantoms. A knee phantom was also developed for purposes of calibrations of in vivo XRF measurement of lead in the patella. XRF measurement results using this phantom were compared to results of XRF measurements made using the plaster-of-Paris (POP) phantoms. A significant difference was observed between the normalized count rates of the two phantom types when either micrograms of lead per gram of bone material or micrograms of lead per gram calcium (bone mineral) is used as the lead content. This difference is consistent with what is observed in real in vivo XRF measurements and indicates the need for the correction factors that are used.

Lodwick, Jeffrey C.

345

Efficacy of nonsurgical interventions for anterior knee pain: systematic review and meta-analysis of randomized trials.  

PubMed

Anterior knee pain is a chronic condition that presents frequently to sports medicine clinics, and can have a long-term impact on participation in physical activity. Conceivably, effective early management may prevent chronicity and facilitate physical activity. Although a variety of nonsurgical interventions have been advocated, previous systematic reviews have consistently been unable to reach conclusions to support their use. Considering a decade has lapsed since publication of the most recent data in these reviews, it is timely to provide an updated synthesis of the literature to assist sports medicine practitioners in making informed, evidence-based decisions. A systematic review and meta-analysis was conducted to evaluate the evidence for nonsurgical interventions for anterior knee pain. A comprehensive search strategy was used to search MEDLINE, EMBASE, CINAHL and Pre-CINAHL, PEDro, PubMed, SportDiscus, Web of Science, BIOSIS Previews, and the full Cochrane Library, while reference lists of included papers and previous systematic reviews were hand searched. Studies were eligible for inclusion if they were randomized clinical trials that used a measure of pain to evaluate at least one nonsurgical intervention over at least 2 weeks in participants with anterior knee pain. A modified version of the PEDro scale was used to rate methodological quality and risk of bias. Effect size calculation and meta-analyses were based on random effects models. Of 48 suitable studies, 27 studies with low-to-moderate risk of bias were included. There was minimal opportunity for meta-analysis because of heterogeneity of interventions, comparators and follow-up times. Meta-analysis of high-quality clinical trials supports the use of a 6-week multimodal physiotherapy programme (standardized mean difference [SMD] 1.08, 95% CI 0.73, 1.43), but does not support the addition of electromyography biofeedback to an exercise programme in the short-term (4 weeks: SMD -0.21, 95% CI -0.64, 0.21; 8-12 weeks: SMD -0.22, 95% CI -0.65, 0.20). Individual study data showed beneficial effects for foot orthoses with and without multimodal physiotherapy (vs flat inserts), exercise (vs control), closed chain exercises (vs open chain exercises), patella taping in conjunction with exercise (vs exercise alone) and acupuncture (vs control). Findings suggest that, in implementing evidence-based practice for the nonsurgical management of anterior knee pain, sports medicine practitioners should prescribe local, proximal and distal components of multimodal physiotherapy in the first instance for suitable patients, and then consider foot orthoses or acupuncture as required. PMID:22149696

Collins, Natalie J; Bisset, Leanne M; Crossley, Kay M; Vicenzino, Bill

2012-01-01

346

Peer review statement  

NASA Astrophysics Data System (ADS)

All papers published in this volume of Journal of Physics: Conference Series have been peer reviewed through processes administered by the editors of the 26th IAHR Symposium on Hydraulic Machinery and Systems proceedings. Reviews were conducted by expert referees from the International Technical Committee to the professional and scientific standards expected of a proceedings journal published by IOP Publishing. The members of the Scientific Committee who selected and reviewed the papers included in the Proceedings of the 26th IAHR Symposium on Hydraulic Machinery and Systems are: Yulin WU Tsinghua University China François AVELLAN EPFL-LMH Switzerland (principal) Xingqi LUO Xi'an University of Sci & Tech China Martin BÖHLE Kaiserslautern University Germany Gerard BOIS Arts et Métiers ParisTech France Luca D'AGOSTINO University of Pisa Italy Eduard EGUSQUIZA Polytechnical University Catalonia Spain Richard FISHER Voith Hydro Inc USA Regiane FORTES-PATELLA Institute Polytechnique de Grenoble France Aleksandar GAJIC University of Belgrade Serbia Wei YANG China Agriculture University China YinLu YOUNG University of Michigan USA Adrian LUNGU Dunarea de Jos University of Galati Romania Arpad FAY University of Miskolcz Hungary José GONZÁLEZ Universidad de Oviedo Spain Baoshan ZHU Tsinghua University China Hongxun CHEN Shanghai University China Chisachi KATO University of Tokyo Japan Zhenyue MA Dalian University of Sci & Tech China Honggang FAN Tsinghua University China François GUIBAULT Ecole Polytechnique de Montreal Canada Pengcheng GUO Xian University of Technology China Leqing WANG Zhejiang University China Toshiaki IKOHAGI Tohoku University Japan Jiandong YANG Wuhan University China Jianzhong ZHOU Huazhong University of Sci & Tech China Jinwei LI NULL China Rennian LI Lanzhou University of Sci & Tech China Houlin LIU NULL China Juan LIU Tsinghua University China Shuhong LIU Tsinghua University China Xianwu LUO Tsinghua University China Michihiro NISHI Tsinghua University China Peter PELZ Darmstadt University Germany František POCHYLY Brno University Czech Republic Rudolf SCHILLING Technische Universität München Germany Minguan YANG Jiangsu University China Smaine KOUIDRI Université Pierre et Marie Curie (Paris 6) France Kazuhiro TANAKA Kyushu Institute of Technology Japan Xuelin TANG Tsinghua University China Yoshinobu TSUJIMOTO Osaka University Japan Fujun WANG China Agriculture University China Guoyu WANG Beijing University of Sci & Tech China Wenwu SONG NULL China Zhengwei WANG Tsinghua University China Hongyuan XU Tsinghua University China Lefu XIAO NULL China Fan YANG Tsinghua University China Yuan ZHENG Hehai University China Zhigang ZUO Tsinghua University China Hongwu ZHU China Petroleum University China Lixiang ZHANG Yunnan University of Sci & Tech China Shengchang ZHANG Zhejiang University of Tech China

2012-11-01

347

Interleukin-6 reduces cartilage destruction during experimental arthritis. A study in interleukin-6-deficient mice.  

PubMed Central

Using interleukin (IL)-6-deficient (IL-6(0/0) mice or wild-type mice, we investigated the controversial role of IL-6 in joint inflammation and cartilage pathology during zymosan-induced arthritis (ZIA). Monoarticular arthritis was elicited by injection of zymosan into the right knee joint cavity. Production of IL-1, tumor necrosis factor (TNF), IL-6, and nitric oxide by the inflamed knee was assessed in washouts of joint capsule specimens. Plasma corticosterone was measured using a radioimmunoassay. Proteoglycan synthesis was assessed using [35S]sulfate incorporation into patellas ex vivo. Joint swelling was quantified by joint uptake of circulating 99mTechnetium pertechnetate. Histology was taken to evaluate cellular infiltration and cartilage damage. Zymosan caused a rapid increase in articular IL-1, IL-6, TNF, and NO levels. Except for IL-6, the released amounts and time course of these mediators were comparable in the IL-6-deficient mice and the wild-type mice. Elevated plasma corticosterone levels were measured during the first day of arthritis in both strains. At day 2 of ZIA, joint inflammation (joint swelling and cell exudate) in IL-6-deficient mice was comparable with that in the wild-type mice. The marked suppression of chondrocyte proteoglycan synthesis and proteoglycan degradation were on the average higher in the IL-6-deficient mice. Together this resulted in a more pronounced proteoglycan depletion in the IL-6-deficient mice as compared with the wild-type mice during the first week of arthritis. Injection of recombinant IL-6 into the joint cavity corrected the IL-6 deficiency and significantly reduced cartilage destruction. Inflammation was more chronic in the wild-type mice, and these mice also showed a higher prevalence for osteophyte formation. In ZIA, IL-6 plays a dual role in connective tissue pathology, reducing proteoglycan loss in the acute phase and enhancing osteophyte formation in the chronic phase. The latter could be related to the more severe joint inflammation as seen in the normal (IL-6-producing) animals during the chronic phase of arthritis. Images Figure 2 Figure 2 PMID:9212744

van de Loo, F. A.; Kuiper, S.; van Enckevort, F. H.; Arntz, O. J.; van den Berg, W. B.

1997-01-01

348

Southwick Osteotomy Stabilised with External Fixator  

PubMed Central

ABSTRACT Introduction: Epiphysiolysis of the femoral head is the most common accident occurring towards the end of pre-puberty and puberty growth. Case report: The author describes the experience in the treatment of chronic epiphysiolysis in two patients treated by Southwick osteotomy. The site is accessed by way of a 15-cm long lateral skin incision and the trochanteric region is reached through the layers. The osteotomy angles prepared beforehand on a thin aluminium model are used to mark the Southwick osteotomy site on the anterior and lateral sides at the level of the lesser trochanter. Before performing the trochanteric osteotomy, two Mitkovi? convergent pins type M20 are applied distally and proximally, above the planned osteotomy site. A tenotomy of the iliopsas muscle is performed, and then the previously marked bone triangle is redissected up to three quarters of the width of the femur. The distal part of the femur is rotated inwards, so that the patella is turned towards the ceiling. The osteotomised fragments of the femur are adapted, repositioned and fixated by installing an external fixator on the previously placed pins. Two more pins are placed, one proximally and one distally, with a view to adequately stabilising the femur. The patient was mobile from day two after the surgery. If, after the surgery, the lead surgeon realises that there is a requirement to make a correction of 5, 10 and 15 degrees of the valgus, varus, anteversion or retroversion deformity, the correction shall be performed without surgically opening the patient, using the fixator pins. Conclusion: After performing a Southwick osteotomy it is easier to adapt, reposition and fixate the osteotomised fragments of the femur using a fixator type M20. Adequate stability allows regaining mobility quickly, which in turn is the best prevention of chondrolysis of the hip. It is possible to make post-operative valgus, varus, anteversion and retroversion corrections of 5, 10 and 15 degrees without performing a surgery. Once the osteotomy is healed, the fixator type M20 is removed without any additional surgery. PMID:25568571

Grubor, Predrag; Mitkovic, Milorad; Grubor, Milan

2014-01-01

349

The Safety and Efficacy of Cadaveric Allografts and Titanium Cage as a Fusion Substitutes in Pyogenic Osteomyelitis  

PubMed Central

Objective The safety and efficacy of various fusion substitutes in pyogenic osteomyelitis has not been investigated. We evaluated and compared the cadaveric allograft and titanium cages used to reconstruct, maintain alignment and achieve fusion in the management of pyogenic spinal infection. Methods There were 33 patients with pyogenic osteomyelitis underwent fusion in this study. Fifteen of the 33 patients were operated on by fusion with allografts (cadaveric patella bones) and 18 of those were operated with titanium mesh cages filled with autologous cancellous iliac bone. After the affected disc and vertebral body resection with pus drainage, cadaveric allograft or titanium cages were inserted into the resected space. Posterior transpedicular screw fixation and rod compression in resected space, where cadaveric allograft or titanium cages were inserted, was performed to prevent the malposition in all patients except in 1 case. Recurrent infection was identified by serial erythrocyte sedimentation rate and cross reactive protein follow-up. Osseous union and recurred infection available at a minimum of 2 years following operation was identified. The amount of kyphosis correction and the subsidence were measured radiographically. Results Spinal fusion was achieved in 29 of 33 patients. In the cadaveric allograft group, 93.3% of patient (14 of 15) showed the osseous union while 83.3% of patient (15 of 18) in the titanium cage group showed union. Subsidence was noted in 12 of the patients. Twelve patients (36.3%) showed unsettling amounts of subsidence postoperatively whereas 46.6% of patients in the cadaveric allograft group and 37.7% of patients in the titanium cage group showed similar subsidence, respectively. There were statistical difference in the fusion rate (p=0.397) and subsidence rate (p=0.276) between the two groups. There was significant statistical difference in the postoperative improvement of segmental kyphosis between the two groups (p=0.022), that is the improvement in sagittal alignment was greater in the titanium cage group than in the cadaveric allograft group. There was no case of recurred infection. Conclusion The cadaveric allograft and titanium cages are effective and safe in restoring and maintaining sagittal plane alignment without increased incidence in infection recurrence in pyogenic osteomyelitis. The postoperative improvement of segmental kyphosis was better in the cage group. PMID:22200018

Kim, Hyun Woo; Ryu, Je-il

2011-01-01

350

Risk of Osteoporotic Fractures With Angiotensin II Receptor Blockers Versus Angiotensin-Converting Enzyme Inhibitors in Hypertensive Community-Dwelling Elderly.  

PubMed

Angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) are used to treat hypertension; however, in vivo and clinical studies suggest that ARBs and ACE inhibitors may exert different effects on bone. The association between long-term use of ARBs and ACE inhibitors and fracture requiring medical attention is limited. We conducted a population-based, retrospective cohort study with propensity score matching using administrative databases in Ontario, Canada, to examine the risk of osteoporosis-related fractures in hypertensive elderly treated with ARBs versus ACE inhibitors. We identified a cohort of newly treated hypertensive patients aged 66 years and older who initiated an ACE inhibitor from May 1, 2004, to March 31, 2012, and matched them to ARB users on propensity score, sex, and age at drug initiation. The primary outcome was hip fracture, and secondary outcomes were non-hip major osteoporotic fractures (other femoral, clinical vertebral, forearm, wrist, humerus) and other osteoporotic fractures (pelvis, clavicle, patella, shoulder, upper arm, tibia, fibula, ankle, scapula, ribs, sternum, trunk). We calculated hazard ratios (HRs) using Cox proportional hazards model with robust standard errors. Of the 87,635 patients who initiated treatment, 28,819 (32.9%) started ARBs and 58,816 (67.1%) started ACE inhibitors. Among new ARB users, 27,815 (96.5%) were successfully matched to ACE inhibitor users. Without dose adjustment, no significant association was observed for ARBs relative to ACE inhibitor users for hip fractures (HR?=?0.88; 95% confidence interval [CI] 0.70-1.11), with a decreased risk of other major osteoporotic fractures (HR?=?0.81; CI 0.70-0.93) and no significant association for other osteoporotic fractures (HR?=?0.88; CI 0.74-1.05). When adjusted for dosage, there was no significant difference between the effects of ARBs and ACE inhibitors on hip (HR?=?0.99; CI 0.78-1.25), other major osteoporotic (HR?=?0.87; CI 0.75-1.01), and other osteoporotic fractures (HR?=?0.90; CI 0.74-1.08). PMID:24806397

Butt, Debra A; Mamdani, Muhammad; Gomes, Tara; Lix, Lisa; Lu, Hong; Tu, Karen

2014-11-01

351

Committees  

NASA Astrophysics Data System (ADS)

Leadership Team of the IAHR Committee for Hydraulic Machinery and Systems Eduard EGUSQUIZA, UPC Barcelona, Spain, Chair François AVELLAN, EPFL-LMH, Switzerland, Past Chair Richard K FISHER, Voith Hydro Inc., USA, Past Chair Fidel ARZOLA, Edelca, Venezuela Michel COUSTON, Alstom Hydro, France Niklas DAHLBÄCKCK, Vatenfall, Sweden Normand DESY, Andritz VA TECH Hydro Ltd., Canada Chisachi KATO, University of Tokyo, Japan Andrei LIPEJ, Turboinstitut, Slovenija Torbjørn NIELSEN, NTNU, Norway Romeo SUSAN-RESIGA, 'Politehnica' University Timisoara, Romania Stefan RIEDELBAUCH, Stuggart University, Germany Albert RUPRECHT, Stuttgart University, Germany Qing-Hua SHI, Dong Fang Electrical Machinery Co., China Geraldo TIAGO, Universidade Federal de Itajubá, Brazil International Advisory Committee Shouqi YUAN (principal) Jiangsu University China QingHua SHI (principal) Dong Fang Electrical Machinery Co. China Fidel ARZOLA EDELCA Venezuela Thomas ASCHENBRENNER Voith Hydro GmbH & Co. KG Germany Anton BERGANT Litostroj Power doo Slovenia B C BHAOYAL Research & Technology Centre India Hermod BREKKE NTNU Norway Stuart COULSON Voith Hydro Inc. USA Paul COOPER Fluid Machinery Research Inc USA V A DEMIANOV Power Machines OJSC Russia Bart van ESCH Technische Universiteit Eindhoven Netherland Arno GEHRER Andritz Hydro Graz Austria Akira GOTO Ebara Corporation Japan Adiel GUINZBURG The Boeing Company USA D-H HELLMANN KSB AG Germany Ashvin HOSANGADI Combustion Research and Flow Technology USA Byung-Sun HWANG Korea Institute of Material Science Korea Toshiaki KANEMOTO Kyushu Institute of Technology Japan Mann-Eung KIM Korean Register of Shipping Korea Jiri KOUTNIK Voith Hydro GmbH & Co. KG Germany Jinkook LEE Eaton Corporation USA Young-Ho LEE Korea Maritime University Korea Woo-Seop LIM Hyosung Goodsprings Inc Korea Jun MATSUI Yokohama National University Japan Kazuyoshi Mitsubishi H I Ltd, Japan MIYAGAWA Christophe NICOLET Power Vision Engineering Srl Switzerland Maryse PAGE Hydro Quebec IREQ, Varennes Canada Etienne PARKINSON Andritz Hydro Ltd. Switzerland B V S S S PRASAD Indian Institute of Technology Madras India Stefan RIEDELBAUCH Stuttgart University Germany Michel SABOURIN Alstom Hydro Canada Inc Canada Bruno SCHIAVELLO Flowserve Corporation USA Katsumasa SHIMMEI Hitachi Ltd Japan Christoph SINGRTüN VDMA Germany Ale? SKOTAK CKD Blansko Engineering, a s Czech Republic Toshiaki SUZUKI Toshiba Corporation Japan Andy C C TAN Queensland University of Technology Australia Geraldo TIAGO FILHO Universidade Federal de Itajuba Brazi Thi C VU Andritz Hydro Ltd Canada Satoshi WATANABE Kyushu University Japan S H WINOTO National University of Singapore Singapore Woo-Seong WOO STX Institute of Technology Korea International Technical Committee François AVELLAN (principal) EPFL-LMH Switzerland Xingqi LUO (principal) Xi'an University of Technology China Martin BÖHLE Kaiserslautern University Germany Gerard BOIS ENSAM France Young-Seok CHOI KITECH Korea Luca d'AGOSTINO University of Pisa Italy Eduard EGUSQUIZA Polytechnical University Catalonia Spain Arpad FAY University of Miskolcz Hungary Richard FISHER Voith Hydro Inc USA Regiane FORTES-PATELLA Institute Polytechnique de Grenoble France Aleksandar GAJIC University of Belgrade Serbia José GONZÁLEZ Universidad de Oviedo Spain François GUIBAULT Ecole Polytechnique de Montreal Canada Toshiaki IKOHAGI Tohoku University Japan Chisachi KATO University of Tokyo Japan Kwang-Yong KIM Inha University Korea Youn-Jea KIM Sungkyunkwan University Korea Smaine KOUIDRI Université Pierre et Marie Curie (Paris 6) France Shengcai LI Warwick University UK Adrian LUNGU Dunarea de Jos University of Galati Romania Torbjøm K NIELSEN NTNU Norway Michihiro NISHI Tsinghua University China Peter PELZ Darmstadt University Germany Frantisek POCHYLY Brno University Czech Republic Albert RUPRECHT University of Stuttgart Germany Rudolf SCHILLING Technische University München Germany Wei SHYY HKUST Hong Kong,China Romeo SUSAN-RESIGA Politehnica University of Timisoara Romania Kazuhiro TANAKA Kyushu Institute of

2012-11-01

352

Effect of Breast Milk Lead on Infant Blood Lead Levels at 1 Month of Age  

PubMed Central

Nursing infants may be exposed to lead from breast milk, but relatively few data exist with which to evaluate and quantify this relationship. This route of exposure constitutes a potential infant hazard from mothers with current ongoing exposure to lead as well as from mothers who have been exposed previously due to the redistribution of cumulative maternal bone lead stores. We studied the relationship between maternal breast milk lead and infant blood lead levels among 255 mother–infant pairs exclusively or partially breast-feeding through 1 month of age in Mexico City. A rigorous, well-validated technique was used to collect, prepare, and analyze the samples of breast milk to minimize the potential for environmental contamination and maximize the percent recovery of lead. Umbilical cord and maternal blood lead were measured at delivery; 1 month after delivery (± 5 days) maternal blood, bone, and breast milk and infant blood lead levels were obtained. Levels of lead at 1 month postpartum were, for breast milk, 0.3–8.0 ?g/L (mean ± SD, 1.5 ± 1.2); maternal blood lead, 2.9–29.9 ?g/dL (mean ± SD, 9.4 ± 4.5); and infant blood lead, 1.0–23.1 ?g/dL (mean ± SD, 5.5 ± 3.0). Infant blood lead at 1 month postpartum was significantly correlated with umbilical cord (Spearman correlation coefficient rS = 0.40, p < 0.0001) and maternal (rS = 0.42, p < 0.0001) blood lead at delivery and with maternal blood (rS = 0.67, p < 0.0001), patella (rS = 0.19, p = 0.004), and breast milk (rS = 0.32, p < 0.0001) lead at 1 month postpartum. Adjusting for cord blood lead, infant weight change, and reported breast-feeding status, a difference of approximately 2 ?g/L (ppb; from the midpoint of the lowest quartile to the midpoint of the highest quartile) breast milk lead was associated with a 0.82 ?g/dL increase in blood lead for breast-feeding infants at 1 month of age. Breast milk lead accounted for 12% of the variance of infant blood lead levels, whereas maternal blood lead accounted for 30%. Although these levels of lead in breast milk were low, they clearly have a strong influence on infant blood lead levels over and above the influence of maternal blood lead. Additional information on the lead content of dietary alternatives and interactions with other nutritional factors should be considered. However, because human milk is the best and most complete nutritional source for young infants, breast-feeding should be encouraged because the absolute values of the effects are small within this range of lead concentrations. PMID:15471729

Ettinger, Adrienne S.; Téllez-Rojo, Martha María; Amarasiriwardena, Chitra; Bellinger, David; Peterson, Karen; Schwartz, Joel; Hu, Howard; Hernández-Avila, Mauricio

2004-01-01

353

Functional Outcomes of Mpfl Reconstruction VS. Graft Tissue Placement  

PubMed Central

Background The medial patellofemoral ligament (MPFL) is essential for the maintenance of correct biomechanical function of the knee. Reconstruction of the MPFL is commonly used in the restoration of patellofemoral stability after traumatic lateral subluxation of the patella. Although a method to accurately determine the MPFL's insertion point has been described, it remains unclear if anatomic placement of MPFL graft tissue is essential for preservation of knee function after MPFL reconstruction. Thus, the purpose of this study was to determine the importance of anatomic placement of MPFL graft tissue for the preservation of knee function following MPFL reconstruction operations. Methods Twenty-seven subjects who underwent MPFL reconstruction operations were retrospectively analyzed. Postoperative radiographs were reviewed. Measurements were taken, and the placement of each patient's MPFL graft tissue was determined to be anatomic or non-anatomic based on radiographic methods previously described in the literature. Each subject's electronic medical record was then reviewed, and clinical data was recorded. Finally, the clinical outcomes of each patient were compared to placement location of the MPFL graft tissue in their procedure. Results Thirteen patients were found to have anatomic MPFL graft tissue placement, and 14 non-anatomic. A significant post-operative difference was found between groups in the following parameters: WOMAC pain (anatomic mean = 85.71 ± 11.34, non-anatomic mean = 75.00 ± 26.35 p = 0.018), function (anatomic mean = 85.85 ± 9.96, non-anatomic mean = 79.09 ± 24.45, p = 0.017) and in KOOS symptom (anatomic mean = 75.63 ± 11.79, non-anatomic mean = 67.83 ± 22.40, p = 0.024), pain (anatomic mean = 77.54 ± 8.61, non-anatomic mean = 71.39 ± 25.18, p = 0.01), ADL (anatomic mean = 85.85 ± 9.97, non-anatomic mean = 79.09 ± 24.45, p = 0.017) and overall (anatomic mean = 74.61 ± 10.33, non-anatomic mean = 69.41 ± 24.25, p = 0.01) scores. No significant difference was observed for post-op instability (p = 0.290) or apprehension (p = 0.496), improvement in WOMAC or KOOS, 2-week, 6-week, or final 1-year range of motion, WOMAC stiffness, or KOOS sport/recreation or QOL. Conclusion Within the range of graft placement values considered by this study, while no reduction in range of motion was seen, non-anatomic placement of MPFL graft tissue in MPFL reconstruction operations caused increased pain and decreased function, evidenced by post-operative KOOS and WOMAC scores. Clinical Relevance It seems that the pivotal step in MPFL reconstruction operations is ensuring correct patellofemoral tracking via intraoperative electrical femoral nerve stimulation. If this step of the procedure is performed correctly, non-anatomic placement will not limit range of motion, lead to continued apprehension, or affect the overall biomechanical functioning of the knee. PMID:25328457

Larson, Evan; Edwards, Alan; Albright, John

2014-01-01

354

MRI in knee osteoarthritis. Application in diet intervention.  

PubMed

This thesis examines two main hypotheses: 1. Obese knee osteoarthritis (KOA) patients can achieve symptomatic improvements following diet intervention regardless of their level of structural damage and overall joint malfunctioning: 2. Rapid weight-loss in obese patients with KOA will lead to improvements in KOA related pathology that can be assessed and evaluated by MRI. Data for the studies were obtained from obese KOA patients who were recruited for a 16 week diet intervention trial, the CAROT-trial (ClinicalTrials.gov identification no.: NCT00655941). Inclusion criteria were age ? 50 years, BMI ? 30 kg/square metro plus symptomatic and verified KOA. Patients underwent a 16 weeks dietary programme with formula products and counselling. Baseline and week 16 assessments included clinical examinations, MRI and CR of the most symptomatic knee, muscle strength tests, gait analyses, blood samples and collection of patient-reported outcomes with a variety of generic and specific health status questionnaires. MRI scans were graded by the BLOKS and CR was analysed by measuring the mJSW and grading the knee as described by KL. 388 possible subjects were pre-screened, 192 were enrolled. Following the 16 weeks diet intervention 175 patients remained in the study. 187 (97%) MRI scans were completed at baseline, 172 (98 %) MRI scans obtained at week 16 and this left the study with 169 (97%) patients with complete MRI datasets at week 16. No statistical significant differences were detected between baseline characteristics of all the initially included patients (n = 192) and the 169 patients included in the per protocol analyses performed in study III (p < 0.05). In order to apply BLOKS, an extensive MRI scoring system, in study II and III we examined the inter- and intra-observer reliability of the various BLOKS items in study I. Results showed that our assessment team performed as described in the original study defining BLOKS and that the patients in the CAROT-trial were graded as expected. In study II we investigated the impact of diet intervention on KOA symptoms whatever the patient's individual level of joint damage and malfunctioning, and the explanatory variables included high-field MRI, radiographs, and muscle strength in m. quadriceps as well as measurements of the knee-joint alignment axis. Results showed that diet intervention resulted in a symptomatic relief in obese KOA patients, irrespective of their level of structural damage, measures of joint malfunctioning and general pre-study patient characteristics. The final study examined whether or not weight-loss had an immediate impact on MRI assessed BMLs. The results showed that changes seen in the total TF sum of BML scores and maximal BML scores did not differ between patients achieving a major weight loss (> 10%) and those who did not. Furthermore, changes in clinical symptoms and BML scores were not associated. The limitations of this thesis were that the MRI analyses were based on single determinations of MRI variables and that the studies did not assess between scan reliability. The MRI protocol for this study did not include all the recommended sequences for BLOKS. Analysing BMLs with the use of only coronal STIR and T1w sequences is considered adequate for a reasonable assessment of the tibial and femoral bones. However, we recognize the limitations this strategy withholds in terms of correctly assessing BMLs located at the margins of our slices when only having a single plane view included in our MRI protocol. Due to an inadequate coverage we did not analyse BMLs in patella, and this confined the thesis to only study changes in the tibial and femoral bones. BLOKS contains separate scores for effusion and synovitis and we have assessed all MRI scans according to this discrimination well knowing that this procedure is biased and that a recent paper has proposed the combination of the two scores. MRI technology allows for an excellent discrimination and delineation of synovitis and synovial effusion by performing MRI with I.V. gadolinium and post-contrast

Gudbergsen, Henrik

2013-03-01