Results of anatomic lateral ankle ligament reconstruction with tendon allograft

Abstract

Chronic ankle instability can be addressed surgically through direct lateral ligament repair, non-anatomic reconstruction, or anatomic reconstruction. The goal of this study was to assess the radiographic, functional, and clinical results of patients undergoing an anatomic lateral ankle ligament reconstruction using an anterior tibial tendon allograft. Eleven patients (12 feet; mean age, 48.9 ± 11.4 years) undergoing lateral ankle ligament reconstruction were followed at a mean of 3.5 ± 1.7 years after surgery (range, 1.2 to 5.0 years). Indications for surgery were previous failed repair (i.e., Broström; one case), hyperlaxity (seven cases), and high-demand patients (four cases). Subjective outcomes including the Foot and Ankle Outcome Score (FAOS), SF-36, and activity level were assessed. Mortise and lateral ankle stress radiographs were performed. The FAOS daily activity and sports activity subscores were 93.4 (range, 77.9 to 100) and 78.6 (range, 30 to 100), respectively. The SF-36v2 physical health and mental health components were 50.4 (range, 30.6 to 65.7) and 45.0 (range, 24.8 to 68.0), respectively. Four patients (five feet) reported no restriction; six patients reported mild restrictions, and one patient reported moderate activity restrictions. Tibiotalar tilt improved significantly from 20.2° to 4.6° after surgery (p < 0.01). The radiographic anterior displacement of the talus from the tibia was 6.5 mm postoperatively. The technique described restores mechanical stability in patients with chronic lateral ankle instability and may be considered in a select group of patients.

Keywords: allograft; anatomic ligament reconstruction; anterior tibial tendon; chronic ankle instability; lateral ligaments.

Fig. 1

Schematic drawing of reconstruction. The tendon, after being fixed to the talus, is first passed through the superior fibular bone tunnel. It is then passed in an anti-parallel fashion through the inferior fibular bone tunnel before being passed lateral to medial through the calcaneal bone tunnel

Fig. 2

Mortise radiograph stress test. The amount of talar tilt, measured as the angle (in degrees) between the superior surface of the talus and the tibial plafond, was assessed using a mortise radiograph of the ankle. Maximal manual pressure was used to exert an inversion/varus force across the ankle joint. The talar tilt improved 43.1° preoperatively (a) to 5.6° postoperatively (b)

Fig. 3

Lateral radiograph stress test. Radiographic anterior translation of the talus was assessed by measuring the nearest distance from the posterior edge of the distal tibial plafond (a) to the posterior edge of the joint surface on the talar dome (b). Maximal manual pressure was used to exert anterior translation of the talus