2.2. Case 2
A 59-year-old female patient who complained of serious pain in the left knee and ipsilateral ankle for about one year presented at our clinic in July 2019. She had no systemic musculoskeletal disease or other medical history. She was 157.0 cm in height and 62.0 kg in weight, with a body mass index of 25.2 kg/m2. The HSS score of the left knee was 69. The osteoarthritic ankle stage was Takakura’s classification stage 3.
Kellgren-Lawrence (K-L) grade II~III osteoarthritic change of the left knee was documented. The weight-bearing X-ray showed the varus deformity, and the hip-knee-ankle (HKA) angle was 4.5°. Her ankle was noted to have 19.5° of varus TT and 5.2° of TI (Fig. 3).
Through a medial approach above the pes anserinus, an opening wedge HTO was performed. Intraoperatively, the medial osteotomy wedge was opened to 6° and the desired correction was achieved. The pain on the knee and ankle joints had disappeared three months after HTO. The HSS score of the left knee was 85 three months after surgery.
The postoperative weight-bearing X-ray showed favorable limb alignment on the coronal view. The standing HKA angle improved from a preoperative value of 4.5° to -1.4° at follow-up. The TT was corrected from 19.5° to 10.6° and the TI from 5.2° to 0.5° (Fig. 4).