A Pragmatic, Multi-center, Multi-surgeon Prospective Outcome Study on Immediate Pain-dependent Weight-bearing Without Immobilization After Surgically Treated Ankle Fractures

Background Ankle fractures are among the most common fractures in adulthood. Various novel surgical treatment strategies have been developed but nothing has changed regarding the postoperative treatment protocol. Although previous studies indicated that early pain dependent weight-bearing without immobilization in surgically treated ankle fractures is safe, these studies were underpowered.

Therefore, the aim of this pragmatic, multi-center, multi-surgeon, prospective outcome study is to investigate complication rates and clinical outcome following mobilization and pain-dependent full weight-bearing in a large cohort of patients with surgically treated ankle fractures.

Methods The herein proposed study is a pragmatic, multi-center, multi-surgeon, prospective outcome study. Included patients must be independently living and mobile and at least 18 years. Included will be any isolated ankle fracture which was treated surgically without additional syndesmotic stabilization (suture-button or syndesmotic screw). Patients will be recruited following surgical treatment and are advised to conduct pain-dependent full weight-bearing without immobilization starting at the day of study inclusion. The use of crutches is allowed per the individual patients demands. Patients will be invited for follow-up visits at 6 weeks, 3-, 6-, and 12 months. Data assessment at each study point includes radiographic follow-up, complication assessment, return to work/sports, rang of ankle motion, and patient-rated outcome scores (MoxFQ, EFAS, OMAS, EQ-5D-5L). Two primary outcome parameters will be assessed: (1) Complications at 3 months; (2) Patient-rated outcome at 12 months. The sample size calculation revealed a final total sample size of 360 patients. The principle statistical evaluation will be descriptive. For the secondary outcome parameters, a multi-variant regression model will be calculated, individually for complication rates and the patient-rated outcome measures.

Discussion Early pain dependent weightbearing bears the chances to increase patient satisfaction, decrease the time of recovery, and improve the overall patient-rated outcome. These chances must we weighted against a possibly increased risk for complications. Still, the limited data available point at a superiority of early pain-dependent weight-bearing. Due to the high patient number, the herein proposed study is the first to provide resilient data capable of changing the current postoperative rehabilitation regime for surgically treated ankle fractures.