Resorbable Polymer Pin Inserted with Ultrasound Activated BoneWelding Technique Compared with a Screw for Osteotomy Fixation in the Reverse L Bunion Correction.

Screw fixation of an osteotomy in the first metatarsal for bunion correction represents a compromise. The need to return to the operating room for removal exposes patients to added anesthesia risk, expense, time, and possible surgical complications. This article compares screw fixation with a novel new bioresorbable polymer pin that is inserted with an ultrasound activated BoneWelding technique to fixate a bunion correction using a reversed L osteotomy. This article reviews and discusses the present benefits of a time-tested osteotomy that, when fixated with this polymer and BoneWelding technique, offers new solutions for a compromised patient population.

Augmentation of atrophic plantar soft tissue with an acellular dermal allograft: a series review.

Treatment of plantar fat pad migration and atrophy has caused concern for decades. Patients can present with pain, callus formation, or ulceration. The purpose of this article is to review the results of a consecutive series of patients treated for fat pad atrophy of the plantar foot, using a minimally invasive implantation of an acellular human dermal allograft as a tissue augmentation. This material was chosen for the fat pad supplementation because of previous reports of success in tendon and ligament augmentation, wound healing, and interpositional arthroplasty.

Mechanical effect of posterior wire or half-pin configuration on stabilization utilizing a model of circular external fixation of the foot.

BACKGROUND: Numerous studies have addressed biomechanical characteristics of circular external fixation of long bones. The objective of the present study was to evaluate stabilization of a simulated foot model using external fixation with either calcaneal tensioned stopper wires or half-pins. METHODS: Fixation configurations of the calcaneus included two parallel wires, two wires crossing at either 30 degrees or 45 degrees, a 4-mm- and 5-mm-diameter single half-pin, or two half-pins inserted at a cross-angle of either 45 degrees or 90 degrees. All frames were tested in axial compression, anteroposterior (AP) bending, and mediolateral (ML) bending. RESULTS: An increase in wire cross-angle improved the axial and AP bending stabilization but had no influence on ML bending. Utilization of a single calcaneal half-pin instead of two cross-wires resulted in a considerable reduction in ML bending stabilization. Frame configurations with two half-pins substantially improved axial and ML bending stabilization. Due to the medial location of the metatarsal wire stopper, an increase in half-pin cross-angle significantly improved ML bending stiffness under lateral foot loading. Under the medial foot loading, however, the half-pin cross-angle had no effect on ML bending stabilization. Replacement of cross-wires with two half-pins significantly improved the AP bending stiffness only when the half-pin cross-angle was reduced to 45 degrees. In all modes of two half-pin frame loading, the half-pin diameter had a substantial effect on foot stabilization. CONCLUSIONS: Although the wire cross-angle, half-pin cross-angle, and half-pin diameter affect the stability of foot circular external fixation, the influence of these mechanical parameters on foot stabilization is dependent on the mode and location of loading. CLINICAL RELEVANCE: The results of the present mechanical testing can be utilized as a useful guideline for the optimization of circular external fixation of the foot.