Ankle pain after total knee arthroplasty: a study of lower extremity imaging parameters

Purpose : This study investigates the relationship between ankle pain and lower extremity imaging parameters in patients following total knee arthroplasty (TKA). Methods : From September 2023 to February 2024, 41 patients with knee osteoarthritis (KOA) who underwent primary TKA were included in this study. The incidence of ankle pain was assessed six months post-surgery, and lower limb imaging parameters were measured to analyze their relationship with ankle pain. Results : Among the 41 patients, 13 experienced ankle pain six months after TKA, representing 31.7% of the cohort, while 28 patients (68.3%) reported no ankle pain. Preoperatively, the Hip-Knee-Ankle (HKA), Tilt Angle of the Ankle (TAA), Talar Tilt Angle (TTA), and Talus Inclination (TI) in the pain group were significantly greater than those in the ankle painless group (p<0.05). Six months postoperationly, the TAA, TTA, TI, and mechanical Lateral Distal Tibial Angle (mLDTA) in the ankle pain group remained significantly elevated compared to the no ankle pain group (p<0.05). No statistically significant differences were observed in the Anterior Distal Tibial Angle (ADTA) and Hindfoot Alignment view Angle (HAVA) between the two groups, both preoperatively and at six months post-TKA (p>0.05). Receiver operating characteristic (ROC) curve analysis indicated that the area under the curve (AUC) values for ΔHKA and ΔmLDTA in predicting postoperative ankle pain were 0.893 and 0.955, respectively. Conclusion : The findings suggest that excessive correction of knee varus and inadequate compensation at the ankle joint may contribute to the development of ankle joint pain in patients following TKA.