Spatial Anatomy of the Radial Nerve in the Extended Deltopectoral Approach.

The goal of this study was to define safe zones to prevent radial nerve injury in an extended deltopectoral approach. Relative distances of the upper margin (UMRN) and lower margin (LMRN) of the radial nerve to the proximal and distal borders of the pectoralis major and deltoid insertions were measured in 20 cadaveric arms. Four proximal humeral zones were identified (zone I, proximal border of the pectoralis major tendon to the proximal border of the deltoid tendon; zone II, proximal border of the deltoid tendon to the distal border of the pectoralis major tendon; zone III, distal border of the pectoralis major tendon to the distal border of the deltoid tendon; and zone IV, distal to the distal border of the deltoid tendon).

Posterior Inferior Comminution Significantly Influences Torque to Failure in Vertically Oriented Femoral Neck Fractures: A Biomechanical Study.

Objectives: To evaluate axial fracture obliquity and posterior inferior comminution in vertically oriented femoral neck fractures (FNFs) in the physiologically young patient. A biomechanical investigation was designed to evaluate the impact of these fracture elements on torque to failure using cannulated screw (CS) and sliding hip screw fixation.

Methods: Four Pauwels III FNF models were established in synthetic femurs: (1) vertically oriented in the coronal plane (COR), (2) coronal plane with axial obliquity (AX), (3) coronal plane with posterior inferior comminution (CCOM), and (4) coronal plane with axial obliquity and posterior inferior comminution (ACOM).

The significant effect of the medial hamstrings on dynamic knee stability.

Purpose: While hamstring autograft is a popular option for the general population, BTB autograft is still significantly more popular among professional athletes due to concerns of altering knee kinematics with hamstring harvest. This study seeks to quantify the contribution of the medial hamstrings to knee stability.

Methods: Valgus knee laxity, anterior tibial translation, and rotational motion were measured in eight fresh-frozen cadaveric knees after forces were applied on the tibia in each plane (coronal, sagittal, and axial).

Evaluating the Femoral-Side Critical Corner in Posterior Cruciate Ligament Reconstruction: The Effect of Outside-In Versus Inside-Out Creation of Femoral Tunnels on Graft Contact Pressure in a Synthetic Knee Model.

Purpose: To characterize and compare the graft contact characteristics of outside-in (OI) and inside-out (IO) femoral tunnels during single-bundle reconstruction of the anterolateral bundle of the posterior cruciate ligament in a synthetic knee model.

Methods: Femoral tunnels were separately made in 16 synthetic femora (8 OI and 8 IO). Achilles tendon allografts were fixed using suspensory fixation with a pressure sensor between the allograft and femoral tunnel.

Biomechanical Analysis of an S1 Pedicle Screw Salvage Technique via a Superior Articulating Process Entry Point.

Study Design: Biomechanical, cadaveric study.

Objective: To compare the fixation strength of a novel S1 pedicle screw insertion technique in a revision setting to a standard S1 pedicle screw and an L5 pedicle screw.

Summary Of Background Data: Fusions to the sacrum remain a difficult clinical challenge.

Pelvic discontinuity: modern techniques and outcomes for treating pelvic disassociation.

Pelvic discontinuity is an uncommon condition that usually presents in the revision total hip arthroplasty population. However, its incidence will most likely increase due to the increasing number of primary and revision total hip arthroplasties (THA) done in recent years. Pelvic discontinuity (acetabular disassociation) is perhaps one of the more challenging cases for the hip arthroplasty surgeon to manage.

A common polymorphism in the LDL receptor gene has multiple effects on LDL receptor function.

A common synonymous single nucleotide polymorphism in exon 12 of the low-density lipoprotein receptor (LDLR) gene, rs688, has been associated with increased plasma total and LDL cholesterol in several populations. Using immortalized lymphoblastoid cell lines from a healthy study population, we confirmed an earlier report that the minor allele of rs688 is associated with increased exon 12 alternative splicing (P < 0.05) and showed that this triggered nonsense-mediated decay (NMD) of the alternatively spliced LDLR mRNA.