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BACKGROUND: Many biceps tenodesis (BT) procedures are described for treating proximal biceps pathology. Axillary nerve injury has been reported during BT using bicortical drilling techniques with variable results depending on the location. In addition, there is a risk of potential articular damage during suprapectoral BT. We sought to determine the distance between the axillary nerve and the posterior passage of a bicortical pin, as well as the risk of articular damage, and to analyze whether a lateral inclination of the pin could avoid the chondral risk during suprapectoral BT with bicortical drilling. METHODS: Ten cadaveric shoulders were divided into 2 groups. In the first group, we determined the axillary nerve distance from the posterior exit point of 3 pins in a suprapectoral position 15 mm distal to the humeral cartilage: perpendicular, 10° caudal, and 20° caudal inclination. We measured 2 distances from the pin: to the axillary nerve and to the cartilage border. In the second group, we set one pin at the same perpendicular position and set the second pin 15° laterally tilted to determine its extra-articular passage. RESULTS: No pin injured the nerve, whereas all pins showed a transchondral direction. The 20° caudal inclination was the nearest to the nerve (18.8 mm [95% confidence interval, 5.5-32 mm]), but the perpendicular position was the safer position (38.8 mm [95% confidence interval, 28-49.6 mm]). Tilting the pin direction 15° laterally prevented cartilage damage (P = .008). CONCLUSIONS: Suprapectoral BT with bicortical drilling performed 15 mm distal to the humeral cartilage is a safe procedure regarding the axillary nerve. A potential humeral chondral injury could be prevented with 15° of lateral inclination of the pin guide.

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BACKGROUND: An anterior cruciate ligament (ACL) rupture is a frequent injury, with short and long-term consequences if left untreated. With a view to benefitting as many patients as possible and preventing future complications, we created a low-cost ligament reconstruction technique. METHOD: The present article describes an anatomic ACL reconstruction technique. RESULTS: The technique involves single-band reconstruction, using flexors tendon graft, outside-in tunnel perforation, femoral fixation with metal interference screw and surgical staples (Agrafe) in the longitudinal position. CONCLUSION: We present a simple, easy-to-reproduce technique that, when executed on patients with good bone quality, primarily in the tibia, is effective and inexpensive, favoring its large scale application.

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Se presenta un reporte un caso con una ruptura de tornillo interferencial biodegradable tibial luego de la reconstrucción de ligamento cruzado anterior (LCA) con injerto cuádruple autólogo de semitendinoso y recto interno. Doce meses postoperatorios luego de una recuperación satisfactoria inicia con síntomas de bloqueo y dolor de rodilla. La Resonancia magnética (RM) mostró ruptura del tornillo tibial sin pérdida de la ubicación ni continuidad de la plástica de LCA. Se realizó extracción de la parte rota del tornillo por vía artroscópica. La paciente tuvo una recuperación completa de su rodilla. Éste caso describe posibles causas de ruptura del tornillo biodegradable y se sugiere tomar en cuenta los cuidados necesarios para evitar dicho problema.

We report a case of broken screw from the tibial site of anterior cruciate ligament reconstruction using an autologous ipsilateral semitendinosus-gracilis quadruple graft. Twelve months after initially successful ACL surgery the patient felt locking symptoms and knee pain. MRI showed a broken bioabsorbable interference tibial screw without loss of location or continuity of the ACL graft. At revision arthroscopy the broken part was removed. The patient had full recovery. This case describes possible causes of bioscrew rupture in ACL surgery and we suggest the necessary precautions to avoid this problem.

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Introduction The rupture of the anterior cruciate ligament (ACL) is the most common type of knee injury. Reconstructive surgery is the ‘gold standard’ treatment. During the immediate post-operative period, the fixation of the graft is entirely dependent on the ability of the grafted implant to be secured inside the bone tunnel under the cyclical loads associated with daily tasks. Poor fixation can lead to graft slippage, thus impairing the healing and integration of the graft. The aim of this study was to evaluate the biomechanical performance of tendon graft fixation devices with metallic and bioabsorbable interference screws. Methods Twenty ACL reconstructions were carried out in porcine tibias using deep flexor tendons to fix 9 × 20 mm metallic (n=10) and PLLA 70/30 bioabsorbable screws (n=10). To verify the ability of a construct to resist immediate postoperative (PO) rehabilitation protocols for immediate load bearing, a cyclic loading test was applied with 50-250 N of tensile force at 1 Hz for 1000 cycles, and the displacement was measured at 10, 50, 100, 500 and 1000 load cycles to quantify the slippage of the graft during the test. After the cyclic loading test, a single-cycle load-to-failure test was applied. Results The slippage of the graft using metallic screws did not differ (P = 0.616) from that observed when using bioabsorbable screws. Conclusion The results obtained in this experiment indicate that metallic screws may promote a similar amount of graft slippage during low cyclic loading as bioabsorbable screws. Additionally, there was no difference in the biomechanical performance of these two types of screws during high failure loads.