A biomechanical comparison of plate configuration in distal humerus fractures.

OBJECTIVES: Our aim was to test the hypothesis that two plates placed parallel to each other are stronger and stiffer than plates placed perpendicular to each other for fixation of a distal humerus fracture model. METHODS: We created an artificial distal humeral fracture model by osteotomizing two groups of identical epoxy resin humera. Screw and plate constructs were built to mimic osteosynthesis. In the first group, 3.5-mm reconstruction plates were placed parallel to each other along each of the medial and lateral supracondylar ridges. In the second group, 3.5-mm reconstruction plates were placed perpendicular to each other with a medial supracondylar ridge plate and a posterolateral plate. Stiffness and strength data of the two constructs were obtained by testing to failure with sagittal plane bending forces. RESULTS: The parallel plate group (n = 7) had a mean stiffness of 214.9 +/- 43.3 N/mm and a mean strength of 304.4 +/- 63.5 N. The perpendicular plate group (n = 8) had a mean stiffness of 138.3 +/- 44.6 N/mm and a mean strength of 214.9 +/- 43.3 N. These differences were significant (Student's t test, P < 0.05). CONCLUSIONS: As theoretically expected, a parallel plate configuration is significantly stronger and stiffer than a perpendicular plate configuration when subjected to sagittal bending forces in a distal humerus fracture model.

Artificial ligament reconstruction of sternoclavicular joint instability: report of a novel surgical technique with early results.

Symptomatic instability of the sternoclavicular (SC) joint is an uncommon problem. The majority of patients respond well to nonoperative measures, although a small number require reconstructive surgery for symptomatic instability, with varying surgical techniques reported in the literature. We report a series of 5 operations (in 4 patients) with chronic SC joint instability treated by reconstruction of SC and costoclavicular ligaments using an artificial ligament weave (LARS: Ligament Augmentation and Reconstruction System). Preoperative and postoperative disabilities of the Arm, Shoulder, and Hand (DASH) Scores and Oxford Shoulder Scores were collected to evaluate the outcomes. The patients had a mean age of 20 years (range, 17 to 22 y), with 2 male and 2 female patients. Three of the patients had traumatic dislocation of the SCJ and 1 patient had bilateral symptomatic atraumatic instability. Anterior instability was observed in 4 joints and posterior instability in 1 joint. In all cases, reconstruction was achieved with a 30 mm LARS ligament. Postoperative follow-up was for an average of 29 months (range, 19 to 41 mo). The DASH Score improved from 51.7 points (range, 24.2 to 75.0) preoperatively to 13.7 points (range, 8.3 to 20.8) postoperatively. The Oxford Shoulder Scores improved from 20.6 preoperatively (range, 15 to 32) to 41.8 postoperatively (range, 39 to 47). All patients returned to full activity including competitive sports. In conclusion, stabilization of the SC joint using a LARS ligament with a weave technique is a feasible option for young, active patients with symptomatic SC joint instability after failure of nonoperative treatment.