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Joint Stability (joint + stability)
Selected AbstractsThe proximal hip joint capsule and the zona orbicularis contribute to hip joint stability in distractionJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 8 2009Hiroshi Ito Abstract The structure and function of the proximal hip joint capsule and the zona orbicularis are poorly understood. We hypothesized that the zona orbicularis is an important contributor to hip stability in distraction. In seven cadaveric hip specimens from seven male donors we distracted the femur from the acetabulum in a direction parallel to the femoral shaft with the hip in the neutral position. Eight sequential conditions were assessed: (1) intact specimen (muscle and skin removed), (2) capsule vented, (3) incised iliofemoral ligament, (4) circumferentially incised capsule, (5) partially resected capsule (distal to the zona orbicularis), (6) completely resected capsule, (7) radially incised labrum, and (8) completely resected labrum. The reduction of the distraction load was greatest between the partially resected capsule phase and completely resected capsule phase at 1, 3, and 5 mm joint distraction (p,=,0.018). The proximal to middle part of the capsule, which includes the zona orbicularis, appears grossly and biomechanically to act as a locking ring wrapping around the neck of the femur and is a key structure for hip stability in distraction. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 989,995, 2009 [source] Effect of Casting Procedures on Screw Loosening in UCLA-Type AbutmentsJOURNAL OF PROSTHODONTICS, Issue 2 2006Stefania C. Kano DDS Background: Screw loosening of implant restorations continues to be a complication in implant prosthodontics. Screw joints are subjected to a loss of initially applied torque because of friction and component misfit. It has been suggested that the loss of applied torque is less in machined metal abutments than in cast plastic abutments. Purpose: This study compared the loss of applied torque (detorque) values in machined titanium and in cast UCLA-type abutments for external hex abutment/implant interface. Materials and Methods: Four groups of 12 samples each were evaluated: (1) machined titanium abutments, (2) premachined palladium abutments cast with palladium, (3) plastic abutments cast with nickel-chromium, and (4) plastic abutments cast with cobalt-chromium. Each abutment was torqued to 30 Ncm according to the manufacturer's instructions and detorqued three times. The mean loss of applied torque (detorque) was recorded as a percentage of the torque applied. Group means were calculated and compared using ANOVA and Tukey's LSD test. Results: Mean detorque values were (1) 92.3 ± 2.9%, (2) 81.6 ± 5.0%, (3) 86.4 ± 4.6%, and (4) 84.0 ± 7.0%. Machined abutments demonstrated significantly greater detorque values compared with all cast groups (p < 0.05). No significant differences were found among cast groups. Conclusion: Machined abutments retained a significantly greater percentage of torque compared with cast abutments. Casting procedures decrease the percentage of applied torque, which may influence final screw joint stability. [source] Cranial cruciate stabilitv in the rottweiler and racing greyhound: an in vitro studyJOURNAL OF SMALL ANIMAL PRACTICE, Issue 5 2000C. Wingfield An in vitro biomechanical study of cadaver stifles from rottweilers and racing greyhounds was undertaken to evaluate the contribution of the cranial cruciate ligament to stifle joint stability. This was performed at differing stifle joint angles, first with the joint capsules and ligaments intact and then with all structures removed except for the cranial cruciate ligament. Craniocaudal laxity increased in both breeds as stifle flexion increased. The rottweiler stifle showed greater craniocaudal joint laxity than the racing greyhound at all joint angles between 150° and 110°, but the actual increases in joint laxity between these joint angles were similar for both breeds. Tibial rotation during craniocaudal loading of the stifle increased craniocaudal laxity in both breeds during joint flexion. The relative contribution of the cranial cruciate ligament to cranial stability of the stifle joint increased as the joint flexed and was similar in both breeds. [source] Static orthoses in the prevention of hand dysfunction in rheumatoid arthritis: a review of the literatureMUSCULOSKELETAL CARE, Issue 2 2005DipCOT Lecturer in Occupational Therapy, Jo Adams MSc Abstract Static orthoses are recommended for individuals who have early rheumatoid arthritis (Scottish Intercollegiate Guidelines Network, 2002; College of Occupational Therapists, 2003). These orthoses aim to rest and immobilize weakened joint structures and decrease local inflammation (Janssen et al., 1990; Nicholas et al., 1982); correctly position joints (Nordenskiöld, 1990; Ouellette, 1991); minimize joint contractures (McClure et al., 1994); increase joint stability (Kjeken et al., 1995); relieve pain (Feinberg, 1992; Callinan and Mathiowetz, 1996; Kjeken et al., 1995) and improve function (Janssen et al., 1990; Pagnotta et al., 1998; Nordenskiöld, 1990). Wrist and hand orthoses have been routinely prescribed for individuals with rheumatoid arthritis (RA) for the last 30 years with limited evidence that they are effective in achieving their purported aims. This article reviews the possible deterioration in hand structure that can occur in RA and discusses the theoretical basis for the application of static orthoses in RA. The evidence for the effectiveness of four commonly used static orthoses is then examined. Copyright © 2005 Whurr Publishers Ltd. [source] The effectiveness of a pre-operative home-based physiotherapy programme for chronic anterior cruciate ligament deficiencyPHYSIOTHERAPY RESEARCH INTERNATIONAL, Issue 4 2006SL Keays Abstract Background and Purpose.,Little evidence supports the prescription of pre-operative rehabilitation in the treatment of chronic anterior cruciate ligament-deficient (ACLD) subjects. The aim of the present study was to assess the effectiveness of a specific six-week pre-operative exercise programme on ACLD knees.,Method.,A single, masked, controlled study was designed. This comprised two matched groups of 12 chronically ACLD patients awaiting reconstruction and a group of 12 matched uninjured control subjects. Only one ACLD group received a home-based exercise and educational programme. Assessment before and after the exercise intervention included: knee joint stability (clinical and KT1000 evaluation); muscle strength (Cybex II); standing balance and functional performance (agility, hop and subjective tests).,Results.,At the time of initial assessment there were no statistically significant differences in any measures for the two ACLD groups but both ACLD groups were significantly different from the uninjured control group as regards quadriceps strength and function. Measures taken after six weeks showed no significant improvement in the untreated ACLD group or in the uninjured control group The treated ACLD group showed significant improvement in the following measures: quadriceps strength measured at 60° and 120° per second (p < 0.001); single leg standing balance with eyes closed (p < 0.001); instrumented passive stability at 20,lb (89N) force (p = 0.003); agility and subjective performance (p < 0.001). The incidence of unstable episodes had decreased in the treated ACLD group, reducing further damage to the joint.,Conclusion.,This study leaves little doubt that pre-operative physiotherapy had a positive effect on motor function in ACLD subjects and should be prescribed routinely to maximize muscle stabilizing potential prior to reconstruction. Patients report improved stability and, in certain cases, may avoid surgery. The finding that exercise increased the passive stability of the joint was unexpected and requires further investigation. Copyright © 2006 John Wiley & Sons, Ltd. [source] Elbow joint luxation in a 1-month-old foalAUSTRALIAN VETERINARY JOURNAL, Issue 1-2 2008LM Rubio-Martínez This paper reports on luxation of the elbow joint without concomitant fracture in a 1-month-old foal. Conservative treatment, with closed reduction and full-limb bandaging, including caudal and lateral splints, seemed successful initially, however, failed to provide enough stability and luxation recurred, and open reduction and surgical placement of prosthetic collateral ligaments was required. Luxation of the elbow joint should be considered when acute non-weight bearing forelimb lameness occurs associated with pain and swelling in the area of the elbow in young foals. Closed reduction failed to provide sufficient joint stability. [source] | ||||||||||