Safe Zones for Cerclage Wiring of the Humeral Diaphysis.

Cerclage wiring of the humeral diaphysis entails particular danger to the radial nerve and the deep brachial artery. We sought to delineate safe zones for minimally invasive cerclage wiring of the humeral diaphysis, specifically in relation to the radial nerve and accompanying vasculature. Cerclage wires were percutaneously inserted into three groups of fresh-frozen cadaveric humeri. Group 1-proximal midshaft humerus at 30% of humeral height (n = 4); Group 2-midshaft spiral groove at 45% of humeral height (n = 4); and Group 3-distal midshaft humerus at 60% of humeral height (n = 4). Subsequently, an extensive surgical exploration of the arteries and nerves around the humerus was performed, noting any disturbance to the vessels or nerves and measuring the distance from the cerclage wire to the radial nerve. Neurovascular structures were injured in 75% of specimens when the cerclage wire was inserted at the level of the spiral groove. Both posterior structures, e.g. the radial nerve and the deep brachial artery, and medial structures, e.g., the median nerve and brachial artery, were incarcerated. Application of the cerclage at 30% or 60% of humeral height did not cause neurovascular injury. Minimally invasive application of the cerclage wire at the spiral groove, which is at 45% of humeral height, is likely to cause injury to neurovascular structures. Application of the cerclage at the proximal or distal midshaft humeral areas is associated with less risk of such injury. Clin. Anat. 33:552-557, 2020. © 2019 Wiley Periodicals, Inc.

The Direct Anterior Approach for Hip Revision: Accessing the Entire Femoral Diaphysis Without Endangering the Nerve Supply.

BACKGROUND: The direct anterior approach (DAA) to the hip has been criticized as an approach that is limited to primary arthroplasty only. Our study objective was to demonstrate, in a cadaveric setting, that an alternate extension of the DAA can be used to reach the femur at the posterior border of the lateral vastus muscle without endangering the nerve supply. METHODS: The iliotibial tract is split anteriorly and pulled laterally, thereby opening the interval to the lateral-posterior aspect of the vastus muscle. The muscle fascia is incised at the posterior border to access the femoral diaphysis. The vastus mobilization is started distally and laterally to the greater trochanter, leaving a muscular bridge between the vastus and the medial gluteal muscle intact. If it is necessary to open the femoral cavity for implant retrieval, we perform an anterior wall osteotomy instead of an extended trochanteric osteotomy. RESULTS: It was possible to split the iliotibial band and pull it laterally, thereby exposing the entire vastus lateralis muscle. The junction of the vastus lateralis and vastus intermedius was not encountered in all cases, nor was the nerve supply with all nerve fibers in that interval. CONCLUSION: The alternate technique described here for accessing the femoral diaphysis allows for easy access to the lateral aspect of the vastus lateralis and the femoral diaphysis. Using this technique, it should also be possible to access the femur and perform all necessary reconstructive procedures on it without damaging the surrounding nerve structures.