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Ulnar collateral ligament insufficiency has been shown to result in changes in contact pressure and contact area in the posteromedial elbow. This study used new digital technology to assess the effect of a complete ulnar collateral ligament tear on ulnohumeral contact area, contact pressure, and valgus laxity throughout the throwing motion. Nine elbow cadaveric specimens were tested at 90° and 30° of elbow flexion to simulate the late cocking/early acceleration and deceleration phases of throwing, respectively. A digital sensor was placed in the posteromedial elbow. Each specimen was tested with valgus torque of 2.5 Nm with the anterior band of the ulnar collateral ligament intact and transected. A camera-based motion analysis system was used to measure valgus inclination of the forearm with the applied torque. At 90° of elbow flexion, mean contact area decreased significantly (107.9 mm 2 intact vs 84.9 mm 2 transected, P =.05) and average maximum contact pressure increased significantly (457.6 kPa intact vs 548.6 kPa transected, P 2 intact vs 65.8 mm 2 transected, P =.01) and average maximum contact pressure increased nonsignificantly (365.9 kPa intact vs 450.7 kPa transected, P =.08). Valgus laxity increased significantly at elbow flexion of 90° (1.1° intact vs 3.3° transected, P =.01) and 30° (1.0° intact vs 1.7° transected, P =.05). Ulnar collateral ligament insufficiency was associated with significant changes in contact area, contact pressure, and valgus laxity during both relative flexion (late cocking/early acceleration phase) and relative extension (deceleration phase) moments during the throwing motion arc. [ Orthopedics. 2015; 38(7):e547–e551.]

This article describes a technique of ankle arthrodesis using a triangular external fixation frame and presents the results of biomechanical analysis and clinical experience with the frame. Clinical evaluation of 23 ankle arthrodeses performed using a triangular external fixation frame yielded a 91 .3% fusion rate at an average of 11 weeks postfusion. The triangular frame was 79% suffer than a compression-only external frame in torsion and 39% stiffer in anteroposterior bending. This high rate of fusion is attributed to the elimination of micromotion at the fusion site because of the increased rigidity of the triangular external compression frame.

Surgical training using simulators has been shown to be highly effective but is not available for some applications and is too expensive for many programs. The authors piloted a cadaver-based module with the goal of objectively measuring and significantly improving orthopedic residents’ surgical skills in placing thoracic pedicle screws, an advanced procedure. An experienced spine surgeon placed thoracic pedicle screws in 7 cadavers (T1–T12) to establish the skilled accuracy rate. For this pilot study, 3 orthopedic residents unfamiliar with the procedure were given didactic training for safe thoracic pedicle screw insertion. Each resident instrumented alternating sides of 5 consecutive cadavers (T1–T12). Screw positions were graded by computed tomography in a blinded fashion, with accuracy defined as no shank breach of the pedicle or vertebral body. Results were reviewed with the residents, instruction was repeated, and alternating sides of 5 cadavers were instrumented by the residents. The experienced surgeon accurately placed 67 (82%) of 82 pedicle screws. Residents accurately placed 80 (44%) of 180 pedicle screws in the initial set of specimens and 105 (58%) of 180 pedicle screws in the second set of specimens ( P =.01). Accuracy varied significantly among residents before but not after computed tomography review. The study’s results show that a cadaver-based training module that resembles the clinical setting can be used to teach complex surgical skills to orthopedic residents.

Standard 4-strand repair of Achilles tendon tears is effective, but additional strength may be desirable in patients who are compromised or those with reruptures. Use of a xenograft scaffold has not been investigated biomechanically in Achilles tendon repair. This study compared stiffness, gap formation, and ultimate load to failure with Krackow repair vs Krackow repair augmented with xenograft scaffold in 6 matched pairs of fresh-frozen human lower extremities. The Achilles tendon was transected 4 cm above the calcaneal insertion. Specimens were randomized to receive standard Krackow repair or Krackow repair augmented with a porcine xenograft scaffold. The graft was wrapped around the repaired tendon, sutured to itself with 2-0 FiberWire (Arthrex, Naples, Florida), and attached to the tendon distally and proximally and then medially and laterally. Specimens were loaded for 200 cycles between 5 and 30 N. Load to 5-mm gapping and load to ultimate failure were measured. Xenograft scaffold augmentation of standard Krakow Achilles tendon repair was significantly stronger and stiffer than standard Krackow repair in a biomechanical model immediately after repair (39.0±8.8 vs 24.4±4.6 N/mm; P =.01). The augmented repair group had significantly higher load to ultimate failure than did the Krackow group (862.7±174.0 vs 479.5±65.5 N; P Biological factors remain to be investigated, but this augmentation method could provide additional strength in patients who are compromised or those with reruptures.

After a bone-patellar tendon-bone graft has been harvested and prepared, the graft must be stored while other surgical tasks are completed. We compared the tendon weight and pull-through force of 2 graft storage methods using 8 cadaveric patellar tendon pairs. One specimen in each pair was soaked in normal saline and the other stored in moist gauze. Weight at 0 vs 5, 0 vs 20, and 5 vs 20 minutes of soaking or storage in moist gauze was significantly higher in the soaked group (P