Total Knee Arthroplasty Conversion after Open-wedge High Tibial Osteotomy

Open-wedge High Tibial Osteotomy (HTO) is an effective treatment for Osteoarthritis (OA) of the knee; however, postoperative changes due to HTO can make subsequent Total Knee Arthroplasty (TKA) technically difficult and can affect long-term survival. Medio-lateral stability along with balanced flexion and extension gaps provides a good functional outcome. A 71-year-old man underwent TKA conversion after open-wedge HTO 12 years earlier; the conversion was performed due to arthritic deterioration in the knee. Medial instability was noted because of poor ligament balancing. The residual medial instability was managed with a knee brace due to the unavailability of the constrained prosthesis. Management of persistent mediolateral instability persisting after soft tissue release and balancing ideally requires varus-valgus constraint. TKA conversion after open-wedge HTO requires a special technique and careful preparation before surgery.