Reported models of joint contracture fail to result in severe motion loss. Our purpose was to develop a rabbit model of knee contracture and compare it to another well-accepted model to determine if more severe stiffness can be achieved. Sixteen skeletally mature New Zealand White female rabbits had their right knee operated to create 3-mm defects on the noncartilaginous portions of the femoral condyles, hyperextend the joint to disrupt the posterior capsule, and immobilize the joint in maximum flexion with a Kirschner-wire for 8 weeks (group I). Sixteen additional rabbits were operated on using an identical protocol except for the absence of capsular injury (group II). In each group, mechanical testing was performed at the time of Kirschner-wire release in eight animals, and 16 weeks after remobilization in eight animals. At immobilization release, the average contracture was 76 AE 248 in group I versus 20 AE 108 in group II (p < 0.001). Sixteen weeks after remobilization, the mean contracture was 49 AE 158 group I versus 11 AE 108 in group II (p < 0.001). When associated with bone perforations and immobilization in forced flexion, injury to the posterior capsule results in a severe contracture in the rabbit knee. ß

No abstract

OBJECT Studies comparing surgical treatments for cervical spondylotic myelopathy (CSM) are heterogeneous, using a variety of different quality of life (QOL) outcomes and myelopathy-specific measures. This study sought to evaluate the relationship of these measures to each other, and to better understand their use in evaluating patients with CSM. METHODS A retrospective study was performed in all patients with CSM who underwent either ventral or dorsal cervical spine surgery at a single tertiary-care institution between January 2008 and July 2013. Severity of myelopathy was assessed pre- and postoperatively using both the Nurick scale and the modified Japanese Orthopaedic Association (mJOA) classification of disability. Prospectively collected QOL outcomes data included Pain Disability Questionnaire (PDQ), Patient Health Questionnaire–9 (PHQ-9), and EQ-5D. Spearman rank correlations were calculated to assess the construct convergent validity for each pair of health status measures (HSMs). To assess each HSM’s ability to discriminate favorable EQ-5D index, we performed receiver operating characteristic (ROC) curve analysis and assessed the area under the curve (AUC). RESULTS A total of 119 patients were included. The PDQ total score had the highest correlation with EQ-5D index (Spearman’s rho = −0.82). Neither of the myelopathy scales (mJOA or Nurick) had strong correlations between themselves (0.41) or with the other QOL measures (absolute value range 0.13–0.49). In contrast, the QOL measures correlated relatively well with each other (absolute value range 0.68–0.97). For predicting favorable EQ-5D outcomes, PDQ total score had an AUC of 0.909. The AUCs were significantly greater for the QOL measures in comparison with the myelopathy measures (AUCs were 0.677 and 0.607 for mJOA and Nurick scale scores, respectively). CONCLUSIONS The authors found that all included measures of QOL and CSM-specific (mJOA or Nurick scale) measures were valid and responsive. The PDQ was the most predictive of positive QOL after surgery (as measured by the EQ-5D index) for patients with CSM. The substantially lower correlation between myelopathy and QOL outcomes, compared with the various QOL measures themselves, suggests that these questionnaires are measuring different aspects of the patient experience. Solely assessing the myelopathy or disease-specific signs and symptoms is likely insufficient to fully understand and appreciate clinical outcome in its totality. These questionnaire types should be used together to best evaluate patients pre- and postoperatively.

Patients undergoing CDA tended to be younger and to have less comorbidity, shorter hospital stays, and lower costs. The number of CDAs increased over time, although the percentage remained relatively small in comparison with that for ACDF.