Effect of unicompartmental knee arthroplasty and high tibial osteotomy with tomofix internal fixation in the treatment of unicompartmental knee osteoarthritis

INTRODUCTION: Knee osteoarthritis is a common degenerative disease in the elderly clinically. Cartilage damage, osteophyte formation, joint space narrowing and bone exposure are the main pathological changes, mainly manifested as joint cartilage degeneration [1]. Since the knee joint load of normal people is mainly conducted through the medial side of the knee joint, it is easy to cause degeneration of the medial compartment and then narrow the joint space, which leads to the medial deviation of the lower limb line and the varus deformity of the knee joint. For patients aged 55-65 years with unilateral ventricular osteoarthritis of the knee, the current surgical methods are mostly high tibial osteotomy (HTO) or unicomartmental knee arthroplasty (UKA)[2,3]. HTO always thought to improve lower limb power line to correct deformities, effectively relieve pain and improve function, is an effective method for treatment of osteoarthritis knee inside, high cut bone is typically used in younger patients and patients from physical activity, can effectively reduce the load and delay of knee joint cartilage lesion replacement time, while UKA is more suitable for old age is not active, activity, and patients needs more intense in terms of pain relief. HYPOTHESES: To investigate the clinical effect of unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO) with tomofix internal fixation in the treatment of unicompartmental knee osteoarthritis. METHODS: 60 patients with unicompartmental knee osteoarthritis and varus deformity of the knee joint were randomly divided into two groups: the UKA group (30 cases) and the HTO group (30 cases). The average follow-up time was 6 months, Scores preoperative and postoperative knee joint function, postoperative complications and postoperative pain satisfaction were compared. RESULTS: The scores of HSS, VAS, femorotibial angle(FTA) and active range of motion(ROM) were 82.6 ± 12.9, 1.9 ± 0.8,173.2 ± 1.4,135.2 ± 1.6 in the group of unicompartmental knee arthroplasty (UKA);The scores of HSS, VAS(Visual Analogue Score), femorotibial angle(FTA) and active range of motion(ROM) after tomofix internal fixation used in the group of high tibial osteotomy (HTO)were 81.9 ± 14.3, 1.8 ± 0.9, 174.5 ± 1.8 and 121.1 ± 2.7 . There was no significant difference between the UKA group and HTO group in the scores of HSS, VAS and femorotibial angle(FTA) (P > 0.05). The active range of motion(ROM) of the HTO group was better than that of UKA group (P < 0.05). CONCLUSION: Both unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO) with tomofix internal fixation can improve the knee joint function and symptoms in the treatment of medial compartment osteoarthritis, but the active range of motion(ROM) in HTO group is better than UKA group.