6.1 Arthroscopic and Open Synovectomy/Tenosynovectomy of the Tibiotalar Joint
Synovitis of the tibiotalar joint and/or tenosynovitis with maximum Larsen Stage II destruction. Patients frequently do not have any subjective clinical symptoms.
Detection of isolated synovitis of the tibiotalar joint is often very difficult clinically, and frequently requires additional diagnostic investigation such as ultrasonography and MRI. Isolated synovitis of the tibiotalar joint can usually be addressed arthroscopically.
Open synovectomy is almost always performed if the synovitis is accompanied by tenosynovitis.
The patient must be informed of the potential for intraoperative conversion to an open procedure.
Supine. Ankle in neutral position with toes pointed toward the ceiling. It is usually necessary to place a positioning roll under the ipsilateral buttock in order to compensate for external rotation of hip. A contralateral pelvic support and tilting of the table can be used to achieve a better ankle position. The ankle joint rests approximately 3 to 5 cm over the end of the table.
Mobilize under partial load for 3 weeks to allow for synovial regeneration. Radiosynoviorthesis is usually recommended 6 weeks after arthroscopic synovectomy.
6.2 Tibiotalar Joint Prosthesis
Larsen III–V destruction with significant clinical symptoms. Less than 15° axial deformity if possible. Severe deformities frequently require additional procedures, such as a simultaneous correction arthrodesis of the subtalar joint.
Specific disclosures for patient consent
Prosthetic loosening. Tendon rupture (also secondary). Dislocation of the liner. Medial, lateral malleolar fractures (particular risk in rheumatic patients). Infection with sequelae. Blood vessel and nerve injury.
Prosthesis system from the manufacturer of choice. A TARIC prosthesis manufactured by Implantcast is shown here.
Supine. Ankle in neutral position with toes pointed toward the ceiling. It is usually necessary to place a positioning roll under the ipsilateral buttock in order to compensate for external rotation of hip. A radiograph may be needed.
Joint dislocations are rarely due to supramalleolar causes in rheumatoid patients.
Any axial deviation or deformity of the subtalar joint must be corrected prior to balancing the talotibial joint. If the subtalar joint is intact, correction may involve a calcaneal osteotomy. Should the destruction also involve the subtalar joint, arthrodesis with correction of the axis is recommended (see Chapter 6.4). This can be performed as a one-stage or two-stage procedure.
Once these causes are ruled out, correction can typically be performed articularly.
The largest portion of the misalignment is corrected and aligned as follows:
Removal of all osteophytes.
Release of all soft tissue adhesions (extensive arthrolysis).
Bone resection with the ankle in neutral position, which may allow for partial correction of the resected bone.
Valgus deformity is more frequent in rheumatic patients. The correction is similar to that for a knee prosthesis.
Deformity is caused by a bony defect and the medial ligament is still intact: further intervention is usually not necessary. If there are indications of lateral ligament instability, it may be necessary to perform a plication of the ligament structures or a ligament repair.
Medial ligament insufficiency: a medial ligament plication or augmentation is performed, depending upon the severity. Endoprosthetic replacement of the tibiotalar joint is not an option if there is severe instability of the medial ligament.
Varus deformities are relatively uncommon in rheumatic patients. Persistent instability following a standard approach is usually due to a deltoid ligament contracture. Medial malleolar corrective elongation osteotomy and realignment via an elevated liner are worth considering.
Immediate full-range mobilization. For a stable endoprosthesis, mobilization with full weight bearing in a stability shoe (VACOped, for example) for 6 weeks. Another option is mobilization in a walking cast boot.