Patellar Resurfacing Versus Circumferential Denervation of the Patella in Total Knee Arthroplasty.

This study compared the rates of anterior knee pain and functional outcomes between resurfaced patellas and non-resurfaced patellas with a circumpatellar denervation. One hundred ten patients who underwent patellar resurfacing or a circumpatellar denervation were evaluated for knee pain and functional outcomes at a minimum of 2 years after total knee arthroplasty. There were no significant differences between the 2 groups regarding Knee Society Scores, anterior knee pain scores, or visual analog scale scores. The groups had similar incidences of anterior knee pain. Most patients reported no to mild effect of anterior knee pain on daily living. Patients in each group reported increased pain with kneeling, squatting, and departing an automobile. Similar proportions of patients were disappointed with their overall outcomes in each group. Circumpatellar denervation and patellar resurfacing during total knee arthroplasty lead to similar incidences of anterior knee pain. [Orthopedics. 2016; 39(5):e1019-e1023.].

Glenohumeral articular cartilage lesions: prospective comparison of non-contrast magnetic resonance imaging and findings at arthroscopy.

PURPOSE: The purpose of this study was to assess the diagnostic sensitivity, specificity, accuracy, negative predictive value (NPV), positive predictive value (PPV), and test-retest reliability of magnetic resonance imaging (MRI) for detecting cartilage abnormalities of the glenohumeral joint in comparison with the gold standard of diagnostic arthroscopy. METHODS: Forty-four patients with a preoperative non-contrast MRI study of their affected shoulder underwent arthroscopy by one surgeon for rotator cuff tendinopathy from 2009 to 2010. Articular cartilage defects were prospectively recorded and graded according to the International Cartilage Repair Society classification system at the time of arthroscopy. One year after surgery, the preoperative MRI were reviewed by a board-certified radiologist and the treating surgeon for articular cartilage defects of both the humeral head and the glenoid. Sensitivity, specificity, accuracy, and test-retest reliability were calculated. RESULTS: At arthroscopy, 43% of the shoulders were found to have articular cartilage defects. When the readers' findings were combined, the sensitivity of detecting humeral lesions on MRI was 32%; specificity, 80%; accuracy, 63%; PPV, 57%; and NPV, 66%. The sensitivity of detecting glenoid lesions was 31%; specificity, 86%; accuracy, 76%; PPV, 33%; and NPV, 85%. CONCLUSIONS: This study finds that the overall accuracy of MRI in detecting articular cartilage damage in patients with the clinical diagnosis of subacromial pathology is moderate. LEVEL OF EVIDENCE: Level II, development of diagnostic criteria based on consecutive patients with universally applied reference "gold" standard.

Initial experience with custom-fit total knee replacement: intra-operative events and long-leg coronal alignment.

New technology using magnetic resonance imaging (MRI) allows the surgeon to place total knee replacement components into each patient's pre-arthritic natural alignment. This study evaluated the initial intra-operative experience using this technique. Twenty-one patients had a sagittal MRI of their arthritic knee to determine component placement for a total knee replacement. Cutting guides were machined to control all intra-operative cuts. Intra-operative events were recorded and these knees were compared to a matching cohort of the senior surgeon's previous 30 conventional total knee replacements. Post-operative scanograms were obtained from each patient and coronal alignment was compared to previous studies using conventional and computer-assisted techniques. There were no intra-operative or acute post-operative complications. There were no differences in blood loss and there was a mean decrease in operative time of 14% compared to a cohort of patients with conventional knee replacements. The average deviation from the mechanical axis was 1.2 degrees of varus, which was comparable to previously reported conventional and computer-assisted techniques. Custom-fit total knee replacement appeared to be a safe procedure for uncomplicated cases of osteoarthritis.