Biomechanical Evaluation of Medial Patellofemoral Ligament Reconstruction Grafts Fixed at Nonanatomic Femoral Insertion Points: MPFL Reconstruction And Femoral Tunnel Location.

Background: Improved patient outcomes and decreased patellar instability have been reported after medial patellofemoral ligament (MPFL) reconstruction for recurrent lateral patellar dislocation; however, there is a lack of comparative evidence on functional outcomes associated with different femoral attachment sites for the MPFL graft.

Purpose: To identify differences in MPFL reconstruction graft isometry with femoral tunnel malpositioning, specifically evaluating isometric differences as the femoral position is moved anterior, posterior, proximal, and distal relative to the Schöttle point, the femoral radiographic landmark of the MPFL.

Study Design: Descriptive laboratory study.

Metaphyseal Stem Extension Improves Tibial Stability in Cementless Total Knee Arthroplasty.

Background: The goal was to determine if the addition of a metaphyseal stem extension limits micromotion of a cementless tibial component during cyclic loading in primary total knee arthroplasty. The hypothesis tested was that the use of a 50-mm stem extension on a cementless tibial component would limit motion compared with an identical cementless component without a stem extension.

Methods: The study used 3 variations of a tibial component from the same total knee arthroplasty system.

Biomechanical Comparison of Transosseous Knotless Rotator Cuff Repair Versus Transosseous Equivalent Repair: Half The Anchors With Equivalent Biomechanics?

Purpose: To compare the biomechanics of a transosseous equivalent (TOE) repair using medial and lateral anchors with tape to a transosseous knotless (TOK) tape repair with only laterally placed intraosseous anchors.

Methods: One of 2 different repairs were performed on 8 paired specimens: (1) transosseous equivalent (TOE) tape repair or (2) transosseous knotless (TOK) tape repair. Specimens were mounted on a materials testing machine and loaded in uniaxial tension to measure cyclic construct gap formation, followed by failure testing.

Fixed-Angle, Posteriorly Connected Anterior Cage Reconstruction Improves Stiffness and Decreases Cancellous Subsidence in a Spondylectomy Model.

Study Design: An idealized biomechanical model.

Objective: The aim of this study was to evaluate the biomechanical properties of a construct designed to minimize intervertebral cage subsidence and maximize stiffness.

Summary Of Background Data: Reconstruction after vertebral resection typically involves posterior segmental fixation and anterior interbody support.

Deep transverse metatarsal ligament and static stability of lesser metatarsophalangeal joints: a cadaveric study.

Background: The static support that guides motion around the lesser metatarsophalangeal joints (MTPJs) is complex. Biomechanical studies revealed important roles of both the plantar plane and collateral ligaments. Since part of the plantar plate is attached to the deep transverse metatarsal ligament (DTML), we hypothesized that the transection of the DTML in the intermetatarsal space may substantially reduce the MTPJ stability.

Malaligned dynamic anterior cervical plate: a biomechanical analysis of effectiveness.

Study Design: Biomechanical evaluation.

Objective: To evaluate the kinematic and load-sharing differences of dynamic anterior cervical plates when placed in-line at 0° and off-axis at 20°.

Summary Of Background Data: The use of dynamic anterior cervical plating systems has recently gained popularity due to the theoretical benefit of improved load sharing with graft subsidence.

Role of plantar plate and surgical reconstruction techniques on static stability of lesser metatarsophalangeal joints: a biomechanical study.

Background: Disruption of the plantar plate of the lesser metatarsophalangeal (MTP) joints leads to significant instability. Despite the fact that plantar plate disorders are common, the best mode of treatment remains controversial with operative treatments having variable and somewhat unpredictable clinical outcomes.

Methods: Lesser MTP joints from the second, third, and fourth toes from fresh-frozen cadaver feet were biomechanically tested: (1) intact, (2) with the plantar plate disrupted, and (3) following a Weil osteotomy, a flexor-to-extensor tendon transfer, or a Weil osteotomy with a subsequent flexor-to-extensor tendon transfer with testing in superior subluxation, dorsiflexion, and plantarflexion.