Ankle ligament injuries occur frequently during recreational activities as well as competitive sports1. Although most heal with little medical intervention, recurrent instability can occur in 15% to 48% of patients2-6 and long-term sequelae can occur in up to 50% of patients7. Even following nonoperative treatment such as physiotherapy, bracing, or medication, continued problems may require surgical intervention, and the normal stability and biomechanics of the ankle joint should be reestablished to prevent the development of arthritis8,9.
Several procedures for the reconstruction of the lateral ankle ligaments have been proposed, and the overall success rates of these operations have been reported to be >80%6,9-15. However, reconstruction of the deltoid ligament has received relatively little attention16-20. Moreover, operative management of chronic global ankle instability, including an incompetent deep deltoid ligament, has rarely been described, to the best of our knowledge18,21.
We present a case of combined insufficiency of the medial and lateral ankle ligaments that was treated successfully with simultaneous reconstruction of those ligaments with a semitendinosus tendon allograft.
The patient was informed that data concerning the case would be submitted for publication, and he consented.
A thirty-six-year-old man presented with discomfort in the left ankle. He had sustained an ankle injury seven years earlier during a soccer game, after which recurrent sprains had often occurred with only minor exertion. He did not participate in sports activity as much as he wanted to because of a feeling of the ankle giving way. He was seen at our clinic with symptoms of instability and a clunking sensation in the ankle joint two months after sustaining another, severe ankle injury.
On physical examination, there was no effusion or swelling and there was a full range of motion of the ankle joint. There was some collapse of the medial longitudinal arch in comparison with that on the contralateral side. The heel was in valgus alignment, but it could be brought to neutral with a voluntary heel-rise maneuver, demonstrating integrity of the posterior tibial musculotendinous unit. Manual stress in varus, valgus, and anterior drawer elicited gross subluxation. On resisted pronation, the peroneal tendons were seen grossly to be dislocated out of the groove behind the fibula.
Plain radiographs showed an osseous fragment lying below the medial malleolus, but no arthritic change was noted. Stress radiographs revealed anterior subluxation and exaggerated medial and lateral talar tilt, indicating insufficiency of the medial and lateral ligament complexes of the ankle joint (Figs. 1-A, 1-B, and 1-C). Magnetic resonance images demonstrated disruption of the medial and lateral ligament complexes of the ankle joint (Fig. 2).
With the diagnosis of medial and lateral ligament insufficiency of the ankle joint and peroneal tendon dislocation, operative management was undertaken. A curvilinear incision was made over the medial malleolus. The scarred superficial deltoid ligament was split longitudinally to expose the osseous fragment, which had been avulsed from the tibial attachment of the deep deltoid ligament. The posterior tibialis tendon was meticulously inspected to confirm its integrity, and no degenerative changes were found. A lateral incision was then made from 3 cm proximal to the tip of the lateral malleolus between the fibula and the Achilles tendon to the superior border of the calcaneus. It then turned 45° anteriorly to reach the inferior border of the calcaneus, after which it angulated 90° anteriorly and superiorly to the calcaneocuboid joint (Fig. 3-A). The peroneal tendons were found to be intact, but the peroneal retinaculum was detached from the fibula. It was reattached to its original position on the fibula, and plication of the adjacent soft tissue was performed with one strand of number-2 FiberWire placed through a small-joint corkscrew suture anchor (Arthrex, Naples, Florida).
A medial sliding calcaneal osteotomy was also performed to reduce the stress, created by the hindfoot valgus deformity, on the reconstructed deltoid ligament. The osteotomy site was stabilized with a 6.5-mm cannulated screw (Samwoo, Seoul, South Korea). Then, the medial and lateral ligament complexes were reconstructed with a semitendinosus tendon allograft (CTS, Dayton, Ohio). The nonarticulating portion of the medial surface of the talus (the insertion of the deep deltoid ligament) and the insertion of the anterior talofibular ligament on the talus, which could be identified by remnants of the ligament, were cleared for preparation of the tunnels. A tunnel guide for anterior cruciate ligament reconstruction was utilized to create a 6-mm-diameter tunnel between the center of the nonarticulating portion of the medial surface of the talus and the center of the anterior talofibular ligament insertion on the lateral surface of the talus (Fig. 3-B). Another 6-mm-diameter tunnel was made in the medial malleolus between the anterior and posterior colliculi to recreate the deep portion of the deltoid ligament, and a third 6-mm-diameter tunnel was made in the lateral malleolus, centered about 1 cm anterior to the tip of the lateral malleolus at the center of the fibular attachment of the anterior talofibular ligament.
A semitendinosus tendon allograft was then passed through the three tunnels (in the talus, the medial malleolus [Fig. 3-C], and the lateral malleolus [Fig. 3-D]). Next, the reconstructed ligaments were secured with the ankle in a neutral position. First the medial end was wrapped around a 4.0-mm partially threaded cancellous screw (Synthes, Bettlach, Switzerland) in the medial malleolus so that we could adjust the tension on the lateral side. With the graft under appropriate tension (allowing a full range of motion of the ankle joint but avoiding laxity), it was also fixed to the lateral malleolus by wrapping it around a 3.5-mm fully threaded cancellous screw. We used the remaining tendon graft to augment the reconstruction by suturing it to itself and the remnant of the anterior talofibular ligament. The scarred anterior talofibular ligament and calcaneofibular ligament were advanced and sutured to the lateral malleolus with one strand of number-2 FiberWire placed in the small-joint corkscrew suture anchor that had been used for the repair of the peroneal retinaculum (Figs. 4-A, 4-B, and 4-C).
The ankle was immobilized in neutral alignment in a short leg walking cast for six weeks, after which protected ankle motion was allowed in a stirrup-type ankle brace. Neither running nor jumping was allowed for three months after the surgery, to avoid creating a stress fracture.
At one year and six months after the operation, the patient was satisfied with the ankle, which was stable and had a full range of motion. The peroneal tendons did not subluxate, and there were no symptoms related to the sural nerve or pain related to the calcaneal osteotomy. The heel alignment was neutral in the standing position. Valgus talar tilt on the standing anteroposterior ankle radiograph had improved from 11° preoperatively to 1° postoperatively (compared with 0° on the normal side preoperatively) and valgus talar tilt on the abduction stress radiograph had improved from 16° to 6° (compared with 2° on the normal side preoperatively). Varus talar tilt on the adduction stress radiograph had improved from 17° to 5° (compared with 13° on the normal side preoperatively). Anterior displacement of the talus on anterior drawer testing had improved from 16 mm to 11 mm (compared with 11 mm on the normal side preoperatively) (Figs. 5-A, 5-B, and 5-C). The patient participated in all activities of daily living without any difficulty and was even able to perform physical labor and participate in recreational sports such as soccer and mountain hiking.
The osseous avulsion fracture of the medial deltoid ligament in our patient had probably been neglected for a long time. Medial ankle ligament insufficiency led to repetitive pronation stress on the ankle, which gradually attenuated the medial ligament complex. The medial translation calcaneal osteotomy was performed to reduce the tension on the reconstructed medial ligament by minimizing valgus stress.
We utilized a single lateral exposure for the repair of the peroneal retinaculum, the reconstruction of the lateral ligament complex, and the calcaneal osteotomy. We elevated the skin flaps with extreme caution to avoid causing skin necrosis, and this allowed sufficient access for all three procedures. We recommend this one-incision approach to the lateral side of the ankle as a useful option for complex reconstructions.
Laterally, the reconstructive procedure focused on the anterior talofibular ligament. We decided to not formally reconstruct the calcaneofibular ligament because the calcaneal osteotomy had been performed. The scarred calcaneofibular ligament was augmented by suturing and plication of the neighboring soft tissue. We believe that the result of the reconstruction in our patient was satisfactory even with the residual anterior instability because the contralateral, intact ankle had a similar degree of anterior instability with no symptoms. Although every component of the medial and lateral ligament complexes cannot be reconstructed with use of this technique, its simplicity and successful outcome in this case make it a reasonable surgical option. The determination of isometric points for graft positioning, the tensioning of the graft at the time of fixation, and the methods of graft fixation can be improved to yield an even better outcome.
Various tendon grafts have been proposed for the reconstruction of the lateral and medial ankle ligament complexes. Allografts including semitendinosus13, gracilis4,22,23, palmaris longus24, and bone-patellar tendon-bone grafts25; a synthetic ligament and the extensor digitorum brevis26; the plantaris tendon; and the fascia lata have been suggested for the more commonly performed lateral ligament reconstruction. A plantaris tendon free graft16,27, a vascularized gracilis free muscle transfer16, and a free extensor digitorum longus tendon graft have been proposed for reconstruction of the medial deltoid ligament20. We chose a semitendinosus tendon allograft for the simultaneous reconstruction of the lateral and medial ligament complexes in our patient, and given that the overall stability of the ankle joint at eighteen months after the surgery was satisfactory, it also appears to be a viable option.
In conclusion, we believe that this technique may be a simple and effective method of reconstruction for treatment of global ligamentous insufficiency of the ankle joint.