To explore the early clinical effect of synchronous total and unicompartmental knee arthroplasty in the treatment of bilateral knee osteoarthritis in the same patient.

From January 2018 to December 2020, 16 patients with bilateral knee osteoarthritis who underwent total and unicompartmental knee arthroplasty at the same time were analyzed retrospectively. The operation time, tourniquet time, hospitalization time and blood transfusion rate were recorded. The hip-knee-ankle (HKA) angle and lower limb length of patients after bilateral surgery were compared, and the leg length discrepancy (LLD) was calculated. Knee society score-function (KSS-f), Oxford knee score (OKS), EuroQol Five Dimensions Questionnaire (EQ-5D) and Forgotten joint score (FJS) at 2 years after operation were counted, and Knee society score-clinic (KSS-c) on both sides were recorded.

All patients were followed up for an average of (34.81±6.01) months. The average operation time was (118.63±5.54) minutes, the total tourniquet time was (84.88±5.63) minutes, and the hospital stay was (7.25±1.65) days. No patient needed blood transfusion. The HKA angle and lower limb length on TKA side were similar to those on UKA side, with no significant difference. The change of HKA on TKA side was (7.25±4.33)°, and that on UKA side was (4.17±4.20)°. The change of HKA angle on TKA side was more significant (Z=2.275, P=0.023). The length variation of lower limb on TKA side was (12.66±6.29)mm, while that on UKA side was (5.30±3.05)mm. The length of lower limb on TKA side increased more, with a statistically significant difference (Z=3.103, P=0.002). Two years after operation, the KSS-f score was (82.63±4.70) points, the OKS score was (17.31±3.70) points, the KSS-c score on the TKA side was (78.94±7.41) points, and the UKA side was (83.88±5.77) points, both of which were significantly higher than those before operation (P<0.001). The FJS score was (69.81±4.64), and the EO-5D score was (73.88±8.21). None of the patients had occurred complications, as pulmonary embolism, symptomatic deep vein thrombosis, knee stiffness, joint infection, and the progression of reserved compartmental osteoarthritis.

At the same time, one side of TKA and the other side of UKA are effective methods for the treatment of knee osteoarthritis, which can achieve satisfactory clinical effects, and will not lead to differences in the length of lower limbs after surgery.