Introduction
Total knee arthroplasty (TKA) has proved to be a highly successful procedure for the relief of debilitating pain associated with degenerative joint disease. The 10- to 15-year survivorship of primary TKA now routinely exceeds 90%. However, despite advancements in surgical technique, implant design, and postoperative management, complications continue to be a relatively common. Like infection, tendon rupture, instability which is common complication after TKR, the instability of hind foot alignment has also been reported. We reported about a satisfied case; ankle, foot deformity correction for malrotation after TKA which didn`t performed about correction of knee.
Case Report
68-year patient has visited and showed hind foot malalignment and claw toe deformity after Total knee arthroplasty one year ago. Patient was suffered by pain and feel like paralysis below ankle which was unable to walk about one year ago. Patient have insufficient action on plantarflexion of ankle and have limited ROM of toes. Also we found in standing position patient showed equinovarus deformity of ankle, claw toe deformity of foot and Achilles tightening about 6cm. On AP standing view patient showed genu recurvatum and slightly elevation of right ankle joint. To correct these deformity, we did tibialis anterior tendon transfer, flexor hallucis longus graft, plantar fasciotomy, and ilizarov external fixator applied. AP standing view after deformity correction showed genu recurvatum angle and hind foot alignment was improved and patient feel much better than before surgery.
Discussion
Genu recurvatum deformities are unusual before total knee arthroplasty (TKA), occurring in less than 1% of patients. Because of its rarity, concern may exist regarding the recurrence of the deformity and the potential for instability after TKA. Recurvatum may be associated with a severe osseous deformity, including genu valgum, capsular or ligamentous laxity, and, rarely, neuromuscular disease. In the presence of the latter, a plantarflexion contracture of the ankle also may be present. Therefore, specific attention should be given preoperatively to evaluation of the quadriceps, hamstrings, and gastrocnemius complex. Because genu recurvatum is known to recur in patients with certain neuromuscular disorders, the etiology of the hyperextension deformity must be elucidated thoroughly before surgery. In the absence of neuromuscular disease, however, hyperextension deformities tend not to recur after TKA. Over the past few years, many different procedures for the correction of genu recurvatum have been proposed. The least technically challenging approach is to tighten the extension gap by underresecting the distal femur, using a thicker polyethylene liner, and placing the femoral component in slight flexion. Another option is to tighten the collateral ligaments in extension to obtain a tighter extension gap and prevent hyperextension deformity. The other option is to use a rotating-hinge TKA with an extension stop to reduce the risk of hyperextension instability postoperatively. We focused on the problem of ankle joint due to genu recurvatum and performed an anterior tibialis tendon transfer and plantar fasciotomy as the main operation for soft tissue surgery to correct the malalignment of hind foot and correct the following claw tow deformity. We experienced a satisfactory case in which genu recurvatum was also corrected as a result of the corrected ankle joint.
