Anatomic Lateral Ligament Reconstruction in the Ankle: A Hybrid Technique in the Athletic Population

SLR - December 2012 - Lang

Reference: John G. Kennedy, Niall A. Smyth, Ashraf M. Fansa and Christopher D. Murawski; The American Journal of Sports Medicine 2012 Oct;40(10):2309-17. Epub 2012 Aug 9.

Scientific Literature Review

Reviewed by: Adam M. Lang, DPM
Residency Program: University Hospital – UMDNJ, Newark, NJ

Podiatric Relevance:
Reconstruction of lateral ankle ligamentous pathology usually consists of direct anatomic repair, checkrein tenodesis, or allograft/autograft repair. There is some controversy regarding the best option for surgical repair due to postoperative stiffness, altered joint mechanics, fixation failure, tendon and graft morbidity. The authors sought to overcome common surgical complications by performing a novel reconstructive approach, combining the advantageous principles of anatomic, tenodesis, and autograft repairs to restore mechanical ankle stability in athletes.

Methods:
This was a retrospective Level IV study performed primarily by the senior author which included 57 patients that underwent hybrid anatomical lateral ankle ligament reconstruction using a peroneus longus autograft. Patients were included if they had failed 12 weeks of functional ankle rehabiliation and did not have medial ankle ligament pathology or a body weight of more than 250 lbs. Clinical evaluation was performed on every patient including Ankle Valgus stress test, Anterior Drawer test, and Modified Romberg test. Arthroscopic evaluation of 54/57 ankle joints was also done for additional pathology and treatment if necessary. All patients had a 4.5 cm long x four mm thick peroneus longus autograft harvest and substitution for native ATFL using a standard Arthrex Biotenodesis screw set, 2-0 Vicryl and 4-0 PDS sutures. In addition, CFL plication was performed in 11/57 patients.
Postoperative protocol included: MRI evaluation for cartilaginous, arthritic and soft tissue changes at three months, six months, one year and two years graded by the Outerbridge Classification. Clinical testing by the Senior Author was done at two weeks, six weeks, three months and 12 months. Partial weight bearing and ROM began at four weeks, physical therapy by six weeks and sport-specific drills at 10 weeks. Patients also completed FAOS and SF-12 questionnaires at each visit.

Results:
Mechanical stability was noted in all patients at final follow-up. Functional instability was still present in 12 percent, but some of these patients did not complete physical therapy. Average FAOS score improved from 58 pre-op (range, 22-86 points), to 89 post-op (range, 61-99 points), P < .01 significance. Average SF-12 score improved from 48 pre-op (range, 29-79 points) to 80 post-op (range, 72-97 points), P < .01 significance. Nine percent of the athletes did not return to their pre-surgical level of activity as their functional instability was significant, P < 0.0001. Arthroscopy identified 54/57 hyperemic synovium and 13 osteochondral lesions; treatment of osteochondral talar lesions approached significance for final clinical outcome at P = 0.082, with the FAOS score pre-op being 51 and post-op being 85; other arthroscopic treatments were not significant to overall clinical outcome. Postoperative MRI showed four percent ankle and 14 percent subtalar joint arthrosis. Peroneus longus graft harvest site successfully remodeled in 56/57 patients. There were three complications, two neurapraxia and one superficial infection.

Conclusion:
This novel technique successfully restored mechanical ankle stability. The peroneus longus autograft length of 4.5cm allows a comfortable one cm intra-osseous capture with interference screws in the fibula and the talus respectively, to cover the average length of the ATFL which is 2.48 cm. It prevents compromise of dynamic ankle stability if the peroneus brevis or another tendon is used. Perhaps functional instability can be avoided if physical therapy is completed. Addressing concomitant ankle pathology does not change the outcome of the ligament reconstruction but should always be considered.