Patient Outcomes in a Novel Osseointegrated Device for Transfemoral Amputation: a case series

Abstract

Background Socket suspension (SS) prosthetics are the current standard for transfemoral amputee prosthetic management. The SS systems have been shown to be inefficient in energy transfer, leading to gait alteration, wear discomfort, and skin complications. Many studies have shown osseointegrated (OI) devices are not associated with these problems and offer many benefits. Purpose Through this report the authors will describe surgical outcomes following transfemoral amputation (TFA) surgery using a novel OI device. Methods Patients with problematic TFA were identified from 2013 to 2018 were treated with a novel OI system. Candidate TFA patients identified through record review as part of an IRB authorized retrospective study. The study group all had the following characteristics: (1)No diabetes, (2)no peripheral vascular disease, and (3)mature healed TFA. All study subjects had attempted use of SS and had failed for many reasons related to the skin to socket interface. The outcomes measured recorded included: (1)Q-TFA Scores, (2)SF-36 Score, (3)time coupled per day, (4)resolution of back pain, (5)residual limb pain, and (6)overall satisfaction. Radiographs of implanted stems were reviewed for evidence of loosening or bone on growth. Results A group of TFA patients (11) had been treated with the OI system and agreed for follow up evaluation. Mean age 52 (37-73) years at the time of OI stage I surgery, with a mean time of 9 (3-20) years post amputation to implantation of the OI system. Original indications for the amputation included: 1 chronic osteomyelitis, 1 neoplasm, and 9 traumatic. Mean time to from TFA to OI was 73 months (2- 216). All patients reported a reduction or complete resolution of back pain after OI. Ambulatory/device coupling status reported was mean 12 hours/day. Average Q-TFA Prosthetic use score 66.1, Prosthetic mobility score, 60.2, Problem score 18.2, and Global score 72. Average SF-36 PCS 56.2 and average MCS 70.0. Radiographs reviewed all showed 4 to 6mm of distal circumferential bone reabsorption with robust bone on growth in the diaphysis of the implanted femurs. Conclusion Early data on the effectiveness and safety of the custom Patriot™ OI device is favorable. Future study evaluating long-term device survivorship and patient reported outcomes is warranted. Bone remodeling post implantation and coupling showed positive effects of the system. This study found the custom OI device to be safe and effective in the management of TFA in patients with controlled indications.