Preventing brachial plexus injury during shoulder surgery: a real-time cadaveric study.

BACKGROUND: Brachial plexopathy is not uncommon after shoulder surgery. Although thought to be due to stretch neuropathy, its etiology is poorly understood. This study aimed to identify arm positions and maneuvers that may risk causing brachial plexopathy during shoulder arthroplasty. METHODS: Tensions in the cords of the brachial plexuses of 6 human cadaveric upper limbs were measured using load cells while each limb was placed in different arm positions and while they underwent shoulder hemiarthroplasty and revision reverse arthroplasty. Arthroplasty procedures in 4 specimens were performed with standard limb positioning (unsupported), and 2 specimens were supported from under the elbow (supported). Each cord then underwent biomechanical testing to identify tension corresponding to 10% strain (the stretch neuropathy threshold in animal models). RESULTS: Tensions exceeding 15 N, 11 N, and 9 N in the lateral, medial, and posterior cords, respectively, produced 10% strain. Shoulder abduction >70° and combined external rotation >60° with extension >50° increased medial cord tension above the 10% strain threshold. Medial cord tensions (mean ± standard error of the mean) in unsupported specimens increased over baseline during hemiarthroplasty (sounder insertion [4.7 ± 0.6 N, P = .04], prosthesis impaction [6.1 ± 0.8 N, P = .04], and arthroplasty reduction [5.0 ± 0.7 N, P = .04]) and revision reverse arthroplasty (retractor positioning [7.2 ± 0.8 N, P = .02]). Supported specimens experienced lower tensions than unsupported specimens. CONCLUSIONS: Shoulder abduction >70°, combined external rotation >60° with extension >50°, and downward forces on the humeral shaft may risk causing brachial plexopathy. Retractor placement, sounder insertion, humeral prosthesis impaction, and arthroplasty reduction increase medial cord tensions during shoulder arthroplasty. Supporting the arm from under the elbow protected the brachial plexus in this cadaveric model.

Revision versus primary arthroscopic rotator cuff repair: a 2-year analysis of outcomes in 360 patients.

BACKGROUND: Symptomatic rotator cuff tears are often treated surgically. However, there is a paucity of information regarding the outcomes of revision arthroscopic rotator cuff repairs. PURPOSE: To evaluate the outcome of revision arthroscopic rotator cuff surgery when compared with primary arthroscopic rotator cuff surgery in a large cohort of patients. STUDY DESIGN: Cohort study; Level of evidence, 3. METHOD: A consecutive series of 50 revision arthroscopic rotator cuff repairs performed by a single surgeon, with minimum 2-year follow-up, were retrospectively reviewed using prospectively collected data. As a comparison, 3 primary arthroscopic rotator cuff repair cases (primary group; n = 310) were chosen immediately before each revision case, and 3 were chosen after. Standardized patient-ranked outcomes, examiner-determined assessments, and ultrasound-determined rotator cuff integrity were assessed preoperatively at 6 months and at a minimum of 2 years after surgery. RESULTS: The revision group was older (mean age, 63 years; range, 43-80 years) compared with the primary group (mean age, 60 years; range, 18-88 years) (P < .05) and had larger tear size (mean ± SEM) (4.1 ± 0.5 cm(2)) compared with the primary group (3.0 ± 0.2 cm(2)) (P < .05). Two years after surgery, the primary group reported less pain at rest (P < .02), during sleep (P < .05), and with overhead activity (P < .01) compared with the revision group. The primary group had better passive forward flexion (+13°; P < .05), abduction (+18°; P < .01), internal rotation (+2 vertebral levels; P < .001) and also significantly greater supraspinatus strength (+15 N; P < .001), lift-off strength (+9.3 N; P < .05), and adduction strength (+20 N; P < .01) compared with the revision group at 2 years. When compared with the primary group, the revision group was more satisfied with the overall shoulder function before surgery but was less satisfied with their shoulder function than the primary group at 2 years (P < .005). The retear rate for primary rotator cuff repair was 16% at 6 months and 21% at 2 years, while the retear rate for revision rotator cuff repair was 28% at 6 months and deteriorated to 40% at 2 years (P < .05). CONCLUSION: The short-term clinical outcomes of patients undergoing revision rotator cuff repair were similar to those after primary rotator cuff repair. However, these results did not persist, and by 2 years patients who had revision rotator cuff repair were twice as likely to have retorn compared with those undergoing primary repair. The increase in retear rate in the revision group at 2 years was associated with increased pain, impaired overhead function, less passive motion, weaker strength, and less overall satisfaction with shoulder function.

Ki-67 immuno-histochemistry index in stage III giant cell tumor of the bone.

BACKGROUND: Giant cell tumor is an infrequent and unpredictable bony lesion. Although numerous attempts have been made to predict the behaviour of GCT, there are no definite biological or histological parameters to determine the prognosis or aggressiveness of this lesion MATERIALS AND METHODS: We analyzed Ki 67 immuno-histochemistry of 31 consecutive cases staged III giant cell tumor to determine the clinico-pathological correlation. There were 19 male patients compare to 12 females. The mean age was 33.8 years ranged from 18 to 59 years. Five cases presented with local recurrence prior to wide resection and one case had multiple recurrences there after. Six cases had pulmonary metastases. Expression of Ki 67 antigen was evaluated by immuno-histochemical staining techniques using the avidin-biotin perioxidase complex method using an LSAB2 kit (Dako, Glostrup, Denmark). The primary antibody used in this study was Ki-67 (MIB-I clone, dilution 1:25; Dako). RESULTS: The mean value of Ki-67 index obtained as a percentage of 1000 background cells was 8.15 (ranged 1.00 - 20.0). The median Ki 67 index was 7.5 with standard deviation of 5.12. The Ki 67 index of recurrence tumor was 4.323 compared to 6.05 without recurrence and was not statistically significant (mean difference of 0.865 with p value in independent t test of 0.736). The Ki 67 index was also not statistically significant in the presence of pulmonary metastases with the mean value of metastases group of 6.681 compared to 2.890 without metastases (mean difference of 1.895 with p value in independent t test of 0.424). CONCLUSION: Ki 67 index is not use-full prognostic marker for aggressive type of giant cell tumor of the bone.