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Medial Compartment (medial + compartment)
Selected AbstractsEffect of magnitude and direction of force on laryngeal abduction: Implications for the nerve-muscle pedicle graft techniqueEQUINE VETERINARY JOURNAL, Issue 4 2009P. CRAMP Summary Reasons for performing study: The nerve-muscle pedicle graft technique is a treatment for recurrent laryngeal neuropathy (RLN), but the optimal placement of the pedicles within the cricoarytenoideus dorsalis (CAD) muscle is unknown. Hypothesis: The magnitude and direction of force placed on the muscular process of the left arytenoid cartilage affects the magnitude of laryngeal abduction. Methods: Five larynges were harvested from cadavers. Using increments of 0.98 N, a dead-weight force generator applied a force of 0,14.7 N for 1 min each to the left muscular process at 0, 10, 20, 30, 40, 50, 60 and 70° angles. The rima glottis was photographed digitally 1 min after each force had been applied. Distances between biomarkers (Lines 1,4) and right to left angle quotient (RLQ) were used to assess the degree of left arytenoid abduction. Results: Increasing force from 0,14.7 N progressively and significantly increased the length of all lines and RLQ, indicating abduction. Furthermore, there was a significant interaction between force and angles. Applying forces of 7.84 N or greater (Lines 2,4 and RLQ) or 11.76 N or greater (Line 1) at angles 0, 10, 20 and 30° resulted in significantly greater abduction than applying the same forces at 40, 50, 60 and 70°. Angles of 0,30° correspond with the direction of pull exerted by the lateral compartment of the CAD muscle. Conclusion: In RLN, nerve-muscle pedicle grafts should be placed preferentially in the lateral rather than in the medial compartment of the CAD muscle. Potential relevance: The information presented can be used to assist surgeons in the planning and application of the nerve-muscle pedicle graft procedure. [source] MicroCT evaluation of normal and osteoarthritic bone structure in human knee specimensJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 1 2003Vikas Patel Abstract Although trabecular bone structure has been evaluated, variation with knee compartment and depth from joint surface is not completely understood. Cadaver knees were evaluated with microcomputed tomography analysis for these variations. Objective differences were compared between: medial vs. lateral compartments; femoral vs. tibial bone; and normal vs. arthritic knees. Depth dependent changes in the parameters were observed for the first 6 mm of the cores in normal knees: BV/TV, Tb.N and Conn.D gradually decrease, while Tb.Sp and SMI increase. In the first 6 mm of the normal tibia BV/TV, Tb.N, and Tb.Th are greater than in the femur on both the medial and lateral compartments while Tb.Sp, SMI, and Conn.D are lower. The medial compartment values for BV/TV, Tb.N, Tb.Th and Conn.D are generally greater than for the lateral in both the femur and tibia while Tb.Sp and SMI are lower. In comparison of normal vs. arthritic knees significant differences are observed in the first 6 mm of the medial tibia. With arthritis BV/TV and Tb.Th are lower, while SMI and Tb.Sp are higher. Tb.N and Conn.D show no statistically significant difference. The bone structure variations are, thus, most prominent in the first 6 mm of depth and medial compartment bone is generally more structurally sound than lateral. Severely arthritic bone changes are most prominent in the medial compartment of the tibia and bone structure is less sound in severe arthritis. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] The knee adduction moment during gait in subjects with knee osteoarthritis is more closely correlated with static alignment than radiographic disease severity, toe out angle and painJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 1 2002D. E. Hurwitz This study tested whether the peak external knee adduction moments during walking in subjects with knee osteoarthritis (OA) were correlated with the mechanical axis of the leg, radiographic measures of OA severity, toe out angle or clinical assessments of pain, stiffness or function. Gait analysis was performed on 62 subjects with knee OA and 49 asymptomatic control subjects (normal subjects). The subjects with OA walked with a greater than normal peak adduction moment during early stance (p = 0.027). In the OA group, the mechanical axis was the best single predictor of the peak adduction moment during both early and late stance (R = 0.74, p < 0.001). The radiographic measures of OA severity in the medial compartment were also predictive of both peak adduction moments (R = 0.43 to 0.48, p < 0.001) along with the sum of the WOMAC subscales (R = ,0.33 to ,0.31, p < 0.017). The toe out angle was predictive of the peak adduction moment only during late stance (R = ,0.45, p < 0.001). Once mechanical axis was accounted for, other factors only increased the ability to predict the peak knee adduction moments by 10,18%. While the mechanical axis was indicative of the peak adduction moments, it only accounted for about 50% of its variation, emphasizing the need for a dynamic evaluation of the knee joint loading environment. Understanding which clinical measures of OA are most closely associated with the dynamic knee joint loads may ultimately result in a better understanding of the disease process and the development of therapeutic interventions. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Increased tibiofemoral cartilage contact deformation in patients with anterior cruciate ligament deficiencyARTHRITIS & RHEUMATISM, Issue 12 2009Samuel K. Van de Velde Objective To investigate the in vivo cartilage contact biomechanics of the tibiofemoral joint following anterior cruciate ligament (ACL) injury. Methods Eight patients with an isolated ACL injury in 1 knee, with the contralateral side intact, participated in the study. Both knees were imaged using a specific magnetic resonance sequence to create 3-dimensional models of knee bone and cartilage. Next, each patient performed a lunge motion from 0° to 90° of flexion as images were recorded with a dual fluoroscopic system. The three-dimensional knee models and fluoroscopic images were used to reproduce the in vivo knee position at each flexion angle. With this series of knee models, the location of the tibiofemoral cartilage contact, size of the contact area, cartilage thickness at the contact area, and magnitude of the cartilage contact deformation were compared between intact and ACL-deficient knees. Results Rupture of the ACL changed the cartilage contact biomechanics between 0° and 60° of flexion in the medial compartment of the knee. Compared with the contralateral knee, the location of peak cartilage contact deformation on the tibial plateaus was more posterior and lateral, the contact area was smaller, the average cartilage thickness at the tibial cartilage contact area was thinner, and the resultant magnitude of cartilage contact deformation was increased. Similar changes were observed in the lateral compartment, with increased cartilage contact deformation from 0° to 30° of knee flexion in the presence of ACL deficiency. Conclusion ACL deficiency alters the in vivo cartilage contact biomechanics by shifting the contact location to smaller regions of thinner cartilage and by increasing the magnitude of the cartilage contact deformation. [source] Denuded subchondral bone and knee pain in persons with knee osteoarthritisARTHRITIS & RHEUMATISM, Issue 12 2009Kirsten Moisio Objective It is unclear how articular cartilage loss contributes to pain in patients with knee osteoarthritis (OA). Full-thickness cartilage defects expose the subchondral bone plate. The relationship between denuded bone and pain has not been examined. The aim of this study was to investigate whether the percent of denuded bone is associated with moderate-to-severe knee pain or frequent knee pain and longitudinally with frequent knee pain 2 years after the baseline evaluation. Methods We studied 182 persons with knee OA (305 knees). Applying specialized magnetic resonance imaging techniques, manual segmentation was used to compute cartilage-covered and denuded bone areas for each surface. Moderate-to-severe knee pain was defined as a score of ,40 mm on a knee-specific 100-mm visual analog scale, and frequent knee pain was defined as pain on most days during the past month. Logistic regression and generalized estimating equations were used in analyses, adjusting for age, sex, body mass index, and bone marrow lesions. Results Cross-sectional analyses revealed that moderate-to-severe knee pain was associated with percent denuded bone in the medial compartment (adjusted odds ratio [OR] 3.90, 95% confidence interval [95% CI] 1.33,11.47), in the medial and patellar surfaces together, and in the lateral and patellar surfaces. Frequent knee pain was associated with percent denuded bone in the patellar surface (adjusted OR 3.11, 95% CI 1.24,7.81), in the medial and patellar surfaces, and in the lateral and patellar surfaces. Longitudinal analyses (in 168 knees without frequent knee pain at baseline) revealed that percent denuded bone in the medial and patellar surfaces was associated with frequent incident knee pain (adjusted OR 4.19, 95% CI 1.56,11.22). Conclusion These results support a relationship between subchondral bone plate exposure and prevalent and incident knee pain in patients with knee OA. [source] Long-term effects of chondroitins 4 and 6 sulfate on knee osteoarthritis: The study on osteoarthritis progression prevention, a two-year, randomized, double-blind, placebo-controlled trialARTHRITIS & RHEUMATISM, Issue 2 2009André Kahan Objective To assess the long-term effects of chondroitins 4 and 6 sulfate (CS) on the radiographic progression of, and symptom changes associated with, knee osteoarthritis (OA). Methods We performed an international, randomized, double-blind, placebo-controlled trial in which 622 patients with knee OA were randomly assigned to receive either 800 mg CS (n = 309 patients) or placebo (n = 313 patients) once daily for 2 years. Radiographs of the target knee, using the Lyon schuss view, were obtained at the time of enrollment and at 12, 18, and 24 months. The minimum joint space width (JSW) of the medial compartment of the tibiofemoral joint was assessed by digital image analysis. The primary outcome was the loss in minimum JSW over 2 years. Results The intent-to-treat analysis demonstrated a significant reduction (P < 0.0001) in minimum JSW loss in the CS group (mean ± SEM ,0.07 ± 0.03 mm) as compared with the placebo group (,0.31 ± 0.04 mm). The percentage of patients with radiographic progression ,0.25 mm was significantly reduced in the CS group compared with the placebo group (28% versus 41% [P < 0.0005]; relative risk reduction 33% [95% confidence interval 16,46%]). The number of patients needed to treat was 8 (95% confidence interval 5,17). Pain improved significantly faster in the CS group than in the placebo group (P < 0.01). There were no differences in safety between groups. Conclusion The long-term combined structure-modifying and symptom-modifying effects of CS suggest that it could be a disease-modifying agent in patients with knee OA. [source] Tibial subchondral trabecular volumetric bone density in medial knee joint osteoarthritis using peripheral quantitative computed tomography technologyARTHRITIS & RHEUMATISM, Issue 9 2008Kim L. Bennell Objective Knee osteoarthritis (OA) is an organ-level failure of the joint involving pathologic changes in articular cartilage and bone. This cross-sectional study compared apparent volumetric bone mineral density (vBMD) of proximal tibial subchondral trabecular bone in people with and without knee OA, using peripheral quantitative computed tomography (pQCT). Methods Seventy-five individuals with mild or moderate medial compartment knee OA and 41 asymptomatic controls were recruited. Peripheral QCT was used to measure vBMD of trabecular bone beneath medial and lateral tibiofemoral compartments at levels of 2% and 4% of tibial length, distal to the tibial plateau. Results There was no significant difference in vBMD beneath the overall medial and lateral compartments between the 3 groups. However, in the affected medial compartment of those with moderate OA, lower vBMD was seen in the 2 posterior subregions compared with controls and those with mild knee OA, while higher vBMD was seen in the anteromedial subregion. Beneath the unaffected or lesser affected lateral compartment, significantly lower vBMD was seen at the 2% level in the anterior and lateral subregions of those with moderate disease. Volumetric BMD ratios showed relatively higher vBMD in the medial compartment compared with the lateral compartment, but these ratios were not influenced by disease status. Conclusion Subregional vBMD changes were evident beneath the medial and lateral compartments of those with moderate medial knee OA. Of import, the posterior subchondral trabecular regions of the medial tibial plateau have markedly lower vBMD. [source] Influence of compartmental involvement on the patterns of morbidity in soft tissue sarcoma of the thighCANCER, Issue 1 2009Andreas Rimner MD Abstract BACKGROUD: The authors sought to determine whether differences existed in patterns of outcome and morbidity between the 3 thigh compartments after limb-sparing surgery and postoperative radiation therapy (RT). METHODS: A total of 255 patients with primary soft tissue sarcoma (STS) of the thigh were identified in our sarcoma database (1982,2002). More than 80% of tumors were >5 cm, high grade, and deep; 33% had close or positive microscopic resection margins. Adjuvant RT consisted of brachytherapy alone (BRT; 63%), external beam RT alone (EBRT; 31%), or a combination of brachytherapy and EBRT (6%). There were 125 anterior, 58 medial, and 72 posterior lesions. The 3 compartments were balanced as to tumor grade, size, depth, margin status, and RT type. RESULTS: Overall local control (LC) was 89%, distant metastases-free survival (DMFS) was 61%, and overall survival (OS) was 66% at 5 years (median follow-up, 71 months). Overall rates for complications at 5 years were wound reoperation (10%), edema (13%), joint stiffness (12%), nerve damage (8%), and bone fractures (7%). Wound reoperation and edema were significantly higher for medial-compartment tumors (P = .01 and .005, respectively), whereas nerve damage occurred more frequently in posterior-compartment tumors (P < .001). There were no differences among bone fracture, joint stiffness, DMFS, or OS rates between compartments. CONCLUSIONS: Although tumor control was similar for all 3 compartments, more wound reoperation and edema were observed in the medial compartment, and more nerve damage was noted in the posterior compartment. These results may help guide decisions concerning current patients and improve the design of future treatments tailored to compartments. Cancer 2009. © 2008 American Cancer Society. [source] | ||||||||||