Abstract
INTRODUCTION: The Osseointegration Group of Australia Accelerated Protocol-3 (OGAAP-3) presents the latest iteration of a structured, prospective, clinical-based protocol for single-stage osseointegration surgery in lower limb amputees. Building on the foundational work of OGAAP-1 and OGAAP-2, this protocol incorporates a decade of institutional experience and over 1000 cases using the Osseointegrated Prosthetic Limb system. OGAAP-3 introduces stratified rehabilitation categories-immediate, standard, slow and delayed loading-based on intraoperative findings, residual limb characteristics and patient-specific physiological factors. The surgical approach remains a single-stage procedure, with modifications described for transfemoral and transtibial levels, including primary amputation with simultaneous implant placement. The aim is to enhance safety, optimise functional outcomes and broaden access to osseointegration. METHODS AND ANALYSIS: OGAAP-3 is a prospective registry-based protocol enrolling approximately 50 patients annually at the Osseointegration Group of Australia and affiliated centres, with data collection ongoing since mid-2023 and planned until 2027. Eligibility criteria include adults (aged 18 years or over) with unilateral or bilateral transfemoral or transtibial amputations, as well as primary amputees undergoing concurrent osseointegration. All patients receive osseointegrated implants which are press-fitted into the residual bone. Functional and quality-of-life outcome measures are recorded preoperatively and at defined postoperative follow-up intervals up to 2 years. Postoperative adverse events are also recorded. The preoperative and postoperative values will be compared for each outcome measure, and the outcomes of the OGAAP-3 procedure will be compared with the results of the OGAAP-1 and OGAAP-2 protocol. ETHICS AND DISSEMINATION: This study has received ethics approval by Macquarie University, Sydney, Australia. The study outcomes will be disseminated by publications in peer-reviewed academic journals and presentations at relevant clinical and orthopaedic conferences with final outcome analyses planned following completion of 2-year follow-up in 2027.