Reconstruction of the lateral ligaments: do the anatomical procedures restore physiologic ankle kinematics?

Extensor retinaculum augmentation reinforces anterior talofibular ligament repair

Repair of the anterior talofibular ligament often is augmented with the inferior extensor retinaculum because it is thought to reinforce the primary ligament repair. The additional dissection and suturing extend the duration of surgery, and not all surgeons routinely include inferior extensor retinaculum augmentation in anterior talofibular ligament repairs. To determine whether there is a reasonable basis for this surgery, we ascertained the degree to which inferior extensor retinaculum augmentation reinforced the primary anterior talofibular ligament repair. Matched pairs of cadaveric ankles had controlled inversion while monitoring resistance to inversion, first with the anterior talofibular ligament sectioned, then with primary anterior talofibular ligament repair alone or with inferior extensor retinaculum augmentation. The resistance to ankle inversion was greater at 5 degrees, 10 degrees, 15 degrees, 20 degrees, and 25 degrees rotation in ankles that had inferior extensor retinaculum augmentation. Anterior talofibular ligament failure occurred at similar inversion angles in both treatment groups, but the primary anterior talofibular ligament repair required more torque to fail in the augmented group. With these ankle loading conditions, inferior extensor retinaculum augmentation provided protection to the primary anterior talofibular ligament repair, indicating that broader clinical use of augmentation may be warranted.

Ligament Injury, Reconstruction and Osteoarthritis

PURPOSE OF REVIEW: The recent literature on the factors that initiate and accelerate the progression of osteoarthritis following ligament injuries and their treatment is reviewed. RECENT FINDINGS: The ligament-injured joint is at high risk for osteoarthritis. Current conservative (e.g. rehabilitation) and surgical (e.g. reconstruction) treatment options appear not to reduce osteoarthritis following ligament injury. The extent of osteoarthritis does not appear dependent on which joint is affected, or the presence of damage to other tissues within the joint. Mechanical instability is the likely initiator of osteoarthritis in the ligament-injured patient. SUMMARY: The mechanism osteoarthritis begins with the injury rendering the joint unstable. The instability increases the sliding between the joint surfaces and reduces the efficiency of the muscles, factors that alter joint contact mechanics. The load distribution in the cartilage and underlying bone is disrupted, causing wear and increasing shear, which eventually leads to the osteochondral degeneration. The catalyst to the mechanical process is the inflammation response induced by the injury and sustained during healing. In contrast, the inflammation could be responsible for onset, while the mechanical factors accelerate progression. The mechanisms leading to osteoarthritis following ligament injury have not been fully established. A better understanding of these mechanisms should lead to alternative surgical, drug, and tissue-engineering treatment options, which could eliminate osteoarthritis in these patients. Progress is being made on all fronts. Considering that osteoarthritis is likely to occur despite current treatment options, the best solution may be prevention.

Anatomical reconstruction of the lateral ligaments of the ankle with a gracilis autograft: a new technique using an interference fit anchoring system

BACKGROUND

Few anatomical and minor invasive procedures have been reported for surgical reconstruction of the lateral ligaments to treat lateral instability of the ankle. Furthermore, there are no standards according to which ligaments should be reconstructed.

HYPOTHESIS

A new technique for anatomically reconstructing the lateral ligaments of the ankle using an interference fit anchoring system and determining which ligaments need to be reconstructed according to the results of standard stress radiography of the talocrural and subtalar joints will be effective for treating lateral instability of the ankle.

STUDY DESIGN

Case series; level of evidence, 4.

METHODS

Twenty-one patients with lateral instability of the ankle underwent surgery using the proposed interference fit anchoring system. Standard stress radiographs of the subtalar joint were performed, and if the talocalcaneal angle was less than 10 degrees , only the anterior talofibular ligament was reconstructed; if there was a 10 degrees or greater opening of the talocalcaneal angle, both the anterior talofibular ligament and the calcaneofibular ligament were reconstructed.

RESULTS

In the 17 patients who received only the anterior talofibular ligament reconstruction, the mean talar tilt angle on standard stress radiography of the talocrural joint was 14.5 degrees +/- 1.7 degrees before surgery and 2.6 degrees +/- 0.8 degrees 2 years after surgery (P < .0001). For the 4 patients who had both the anterior talofibular ligament and calcaneofibular ligament reconstructed, the mean talar tilt angle was 16.5 degrees +/- 1.5 degrees before surgery and 3.0 degrees +/- 0.5 degrees 2 years after surgery (P = .0015). The overall mean talocalcaneal angle on standard stress radiography of the subtalar joint was 11.3 degrees +/- 1.4 degrees before surgery and 3.5 degrees +/- 0.8 degrees 2 years after surgery (P = .0060).

CONCLUSION

The proposed system has several advantages, including anatomical reconstruction with normal stability and range of motion restored, the need for only a small incision during the reconstruction, and sufficient strength at the tendon graft-bone tunnel junction, in comparison with the tension strength of the lateral ligaments of the ankle.