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CASE: A 67-year-old woman presented 9 months after a closed midshaft humerus fracture with a new onset radial nerve palsy. Radiographs demonstrated a hypertrophic nonunion. Upon exploration, the radial nerve was in continuity and entrapped in fracture callus. It was extricated from the callus, and an open reduction and plate fixation was performed. Full radial nerve function returned by 3 months. CONCLUSION: We recommend that delayed onset radial nerve palsies be treated on a semiurgent basis with radial nerve exploration and decompression followed by internal fixation to achieve primary bone healing and minimize fracture callus formation.

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During orthopedic surgery, screws are inserted by "subjective feel" in humeri for fracture fixation, that is, stopping torque, while trying to prevent accidental over-tightening that causes screw-bone interface failure, that is, stripping torque. However, no studies exist on stopping torque, stripping torque, or stopping/stripping torque ratio in human or artificial humeri. This study evaluated five types of humeri, namely, human fresh-frozen (n = 19), human embalmed (n = 18), human dried (n = 15), artificial "normal" (n = 13), and artificial "osteoporotic" (n = 13). An orthopedic surgeon used a torque screwdriver to insert 3.5-mm-diameter cortical screws into humeral shafts and 6.5-mm-diameter cancellous screws into humeral heads by "subjective feel" to obtain stopping and stripping torques. The five outcome measures were raw and normalized stopping torque, raw and normalized stripping torque, and stopping/stripping torque ratio. Normalization was done as raw torque/screw-bone interface area. For "gold standard" fresh-frozen humeri, cortical screw tests yielded averages of 1312 N mm (raw stopping torque), 30.4 N/mm (normalized stopping torque), 1721 N mm (raw stripping torque), 39.0 N/mm (normalized stripping torque), and 82% (stopping/stripping torque ratio). Similarly, fresh-frozen humeri gave cancellous screw average results of 307 N mm (raw stopping torque), 0.9 N/mm (normalized stopping torque), 392 N mm (raw stripping torque), 1.2 N/mm (normalized stripping torque), and 79% (stopping/stripping torque ratio). Of the five cortical screw parameters for fresh-frozen humeri versus other groups, statistical equivalence (p ≥ 0.05) occurred in four cases (embalmed), three cases (dried), four cases (artificial "normal"), and four cases (artificial "osteoporotic"). Of the five cancellous screw parameters for fresh-frozen humeri versus other groups, statistical equivalence (p ≥ 0.05) occurred in five cases (embalmed), one case (dried), one case (artificial "normal"), and zero cases (artificial "osteoporotic"). Stopping/stripping torque ratios were relatively constant for all groups at 77%-88% (cortical screws) and 79%-92% (cancellous screws).

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The following study is a review of 3 different treatment methods for treating comminuted distal periprosthetic femur fractures in 23 patients over the age of 70 (average age 80, range 70-90). Reconstruction techniques included 7 allograft prosthesis composite (APC), 9 revision systems (RSA), and 7 distal femur endoprosthesis (DFR). Operative time and blood loss were found to be significantly less in RSA and DFR patients compared to the APC patients. Hospital stay was shortest for the DFR patients. No significant difference was found in the 6-week or 6-month Knee Society Scores. Our preliminary results demonstrate that in experienced hands, distal femur endoprosthesis should be considered in patients with advanced age and poor bone quality who require early mobilization.

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The purpose of the study was to compare the recurrence rate of arthroscopic Bankart repair with suture anchors in collision vs noncollision athletes. Sixty-four patients who underwent arthroscopic shoulder stabilization using suture anchors for recurrent anterior dislocation were identified. Forty-three patients (22 collision and 21 noncollision) were evaluated at a minimum 24-month follow-up. The recurrence rate was reported, and functional outcomes (American Shoulder and Elbow Society, Western Ontario Shoulder Index, and Short Form 12) were evaluated. Statistical analysis was performed using chi-square test and Student's t test with a 95% confidence interval and a significance level set at a P value less than .05. The overall dislocation recurrence rate was 4.6% (2 of 43 patients); the dislocation recurrence rate in collision athletes was 9% (2 of 22 patients), and no redislocations occurred in noncollision athletes. No statistical differences existed in Western Ontario Shoulder Index score (73.5% in collision and 73.4% in noncollision athletes; P=.831), American Shoulder and Elbow Society score (91.2 in collision and 80.7 in noncollision athletes; P=.228), and Short Form 12 score (108.5 in collision and 101.2 in noncollision athletes; P=.083). Average external rotation loss was 6.8° in collision and 5.5° in noncollision athletes (P=.864). Ninety percent of collision athletes vs 95% of noncollision athletes were satisfied. Seventy-three percent of collision and 81% of noncollision athletes were able to return to sport at their preinjury levels. Collision athletes had higher recurrence rates after arthroscopic shoulder stabilization compared with noncollision athletes, but no statistical difference was found. Functional outcomes according to American Shoulder and Elbow Society, Western Ontario Shoulder Index, and Short Form 12 were similar.

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Orthopedic surgeons apply torque to metal screws manually by "subjective feel" to obtain adequate fracture fixation, i.e. stopping torque, and attempt to avoid accidental over-tightening that leads to screw-bone interface failure, i.e. stripping torque. Few studies have quantified stripping torque in human bone, and only one older study from 1980 reported stopping/ stripping torque ratio. The present aim was to measure stopping and stripping torque of cortical and cancellous screws in artificial and human bone over a wide range of densities. Sawbone blocks were obtained having densities from 0.08 to 0.80g/cm(3). Sixteen fresh-frozen human femurs of known standardized bone mineral density (sBMD) were also used. Using a torque screwdriver, 3.5-mm diameter cortical screws and 6.5-mm diameter cancellous screws were inserted for adequate tightening as determined subjectively by an orthopedic surgeon, i.e. stopping torque, and then further tightened until failure of the screw-bone interface, i.e. stripping torque. There were weak (R=0.25) to strong (R=0.99) linear correlations of absolute and normalized torque vs. density or sBMD. Maximum stopping torques normalized by screw thread area engaged by the host material were 15.2N/mm (cortical screws) and 13.4N/mm (cancellous screws) in sawbone blocks and 20.9N/mm (cortical screws) and 6.1N/mm (cancellous screws) in human femurs. Maximum stripping torques normalized by screw thread area engaged by the host material were 23.4N/mm (cortical screws) and 16.8N/mm (cancellous screws) in sawbone blocks and 29.3N/mm (cortical screws) and 8.3N/mm (cancellous screws) in human femurs. Combined average stopping/ stripping torque ratios were 80.8% (cortical screws) and 76.8% (cancellous screws) in sawbone blocks, as well as 66.6% (cortical screws) and 84.5% (cancellous screws) in human femurs. Surgeons should be aware of stripping torque limits for human femurs and monitor stopping torque during surgery. This is the first study of the effect of sawbone density or human bone sBMD on stopping and stripping torque.

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AIMS: Reactive oxygen species (ROS) activate multiple signaling pathways involved in cardiac hypertrophy. Since HO-1 exerts potent antioxidant effects, we hypothesized that this enzyme inhibits ROS-induced cardiomyocyte hypertrophy. METHODS: HL-1 cardiomyocytes were transduced with an adenovirus constitutively expressing HO-1 (AdHO-1) to increase basal HO-1 expression and then exposed to 200 microM hydrogen peroxide (H2O2). Hypertrophy was measured using 3H-leucine incorporation, planar morphometry and cell-size by forward-scatter flow-cytometry. The pro-oxidant effect of H2O2 was assessed by redox sensitive fluorophores. Inducing intracellular redox imbalance resulted in cardiomyocyte hypertrophy through transactivation of nuclear factor kappa B (NF-kappaB). RESULTS: Pre-emptive HO-1 overexpression attenuated the redox imbalance and reduced hypertrophic indices. This is the first time that HO-1 has directly been shown to inhibit oxidant-induced cardiomyocyte hypertrophy by a NF-kappaB-dependent mechanism. CONCLUSION: These results demonstrate that HO-1 inhibits pro-oxidant induced cardiomyocyte hypertrophy and suggest that HO-1 may yield therapeutic potential in treatment of.

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