Comparison of the ALPS and PHILOS plating systems in proximal humeral fracture fixation - a retrospective study.

BACKGROUND: Open reduction and plate osteosynthesis are considered as a successful technique for the treatment of proximal humerus fracture (PHF) despite high complication rates. The objective of our study was to review the clinical outcome and complications of the Anatomic Locking Plate System (ALPS) and compare it to the Proximal Humeral Internal Locking System (PHILOS). Our hypothesis was that ranges of motion (ROM) were superior and complication rates were lower with ALPS. METHODS: Twenty patients treated with ALPS for PHF were retrospectively compared to 27 patients treated with PHILOS. Union, ROM and complications were clinically and radiologically assessed at 6 weeks, 3, 6, 12 and 18-24 months post-operatively. RESULTS: Mean age was 52 ± 14 in the ALPS group and 58 ± 13 in the PHILOS group. Last follow-ups were conducted at a mean of 20.6 ± 4.8 months. Mean shoulder abduction was superior with ALPS by 14° (p-value = 0.036), 15° (p-value = 0.049), and 15° (p-value = 0.049) at 3, 6, and 12 months respectively. Mean shoulder external rotation was superior with ALPS by 11° (p-value = 0.032), 15° (p-value = 0.010) and 12° (p-value = 0.016) at 6 weeks, 3 and 6 months respectively. At the end of the follow-up, ROM remained better with ALPS, but not significantly. Complication rates over 21 months reached 20% with ALPS and 48% with PHILOS (p-value = 0.045). Implant removal rates reached 10% with ALPS and 37% with PHILOS (p-value = 0.036). Avascular necrosis was the only cause for hardware removal in the ALPS group. CONCLUSION: The ALPS group showed better clinical outcomes with faster recovery in abduction and external rotation, although no difference in ROM remained after 21 months. Additionally, the complications rate was lower at last follow up. In our experience, the ALPS plating system is an effective management option in some PHF.

A novel body weight support system extension: initial concept and simulation study.

Body weight supported treadmill training is an approach to gait rehabilitation following a stroke or spinal cord injury. Although lateral control of balance is an important aspect of walking, many of the currently available body weight support systems have a fixed pulley configuration which can lead to lateral forces being developed in the supporting cables, interfering with the lateral balance task. In this paper, a novel extension for body weight support systems, used for treadmill walking, is presented which features a system of pulleys and trolleys. A model is developed for the device along with a basic feedback controller in order to enable simulation of the concept. The lateral forces induced by the novel system are greatly reduced in comparison to a fixed pulley system. This device has applications in balance training within gait rehabilitation programs.