SLR - September 2014 - Katy M. Statler
Reference: Petrera M, Dwyer T, Theodoropoulos JS, Ogilvie-Harris DJ. Short – to Medium – Term Outcomes After a Modified Brostrom Repair for Lateral Ankle Instability with Immediate Postoperative Weightbearing.The American Journal of Sports Medicine. 2014 April 25; 42: 1542-48.
Scientific Literature Review
Reviewed by: Katy M. Statler, DPM
Residency Program: Englewood Hospital and Medical Center
Podiatric Relevance: Ankle sprains are a very common injury. Epidemiologic studies have revealed a total number of ankle sprains approaching two million per year in the United States. The majority of these sprains result from an inversion mechanism where biomechanics can play a huge role. Once the lateral ligament complex in injured, it is susceptible to recurrent instability and injury. Current literature shows that 20 percent of patients with chronic instability will fail conservative treatment and need surgical management. If the chronic instability is left untreated, degenerative changes and osteoarthritis may arise.
Methods: Between the years of 2005 and 2008, 55 patients with chronic lateral ankle instability that failed conservative treatment underwent ligamentous repair using a modified Broström technique (lateral ligament fibular advancement). All patients had a positive anterior drawer and tilt test prior to surgery. An MRI was obtained for each patient pre-operatively resulting in an anterior talofibular ligament (ATFL) tear with or without a calcaneofibular ligament (CFL) tear. The ATFL and CFL were released from the fibula and advanced using two double-loaded metallic suture anchors 3.5mm in size. All surgeries were performed by a single surgeon. Full weight-bearing in a walking boot was permitted from the first postoperative day. Patients were assessed preoperatively and annually using the Foot and Ankle Outcome Score (FAOS). The FAOS includes five subscales separately evaluating pain, other symptoms, function in daily living, function in sport and recreation, and foot and ankle-related quality of life. A normalized score (with 100 indicating no symptoms and 0 indicating extreme symptoms) is calculated for each subscale. Data was collected by various personnel (residents and fellows) and retrospectively reviewed by one of the authors. Complication, failure (recurrent instability), and return-to-sport rates were also recorded.
Results: Six patients (11 percent) were lost to follow-up, leaving a study group of 49 patients (23 men, 26 women). The mean age at the time of surgery was 25 years (range, 18-37), with a mean duration of symptoms of 1.8 years (range, six months to five years). The mean follow-up time was 42 months (range, 24-60 months). Significant improvement was seen in the FAOS from preoperatively to postoperatively (from 36-75.4, P < .001): the pain subscale improved from 35-75 (P <.001), the symptom subscale from 29 to 77 (P=.01), the function subscale from 45 to 77 (P<.001), the function in sports and recreation subscale from 38 to 70 (P<.001), and the foot and ankle related quality of life subscale from 35 to 78 (P<.001). No significant difference in range of motion with the contralateral side was seen (P=.34). The failure rate was 6 percent, with three patients reporting residual instability after a traumatic retear. Two cases of superficial wound infections were seen. One case of temporary neurapraxia of the superficial peroneal nerve was observed. The return -to-sport rate was 94 percent.
Conclusions: This study demonstrates that immediate, protected, full weightbearing after ankle ligament repair with a modified Brodström technique may lead to favorable clinical outcomes, a high rate of return to sports, and a low failure rate. The advantages of the lateral ligament fibular advancement technique relate to the preservation of the anatomy and kinematics of the ankle and subtalar joint, along with strong fixation that enables immediate full weightbearing, early movement, and accelerated rehabilitation.