The Study Of The Short-term Efficacy Of Oxford Medial Unicompartmental Knee Arthroplasty

ObjectiveThe unicompartmental knee arthroplasty (UKA) has been widely used in the treatment of unicompartmental knee osteoarthritis. In this paper, we mainly discuss short-term efficacy and the axial alignment of the lower extremity after Minimally invasive Oxford phase 3 unicompartmental knee arthroplasty.MethodsMethods:We study a retrospective analysis of 38 cases (38 knees) of knee joint disease patients who treated by Minimally invasive Oxford phase 3 unicompartmental knee arthroplasty for isolated medial knee osteoarthritis from 2014 December to 2015 December in the Joint Department of Guangdong Provincial Hospital of traditional Chinese medicine. All the cases were the medial condyle replacement, which include 10 males and 28 females, Age 52-79 (66 on average) years old, Body Mass Index 21-33(27 on average). All of the patients were followed up for 3-14(8.8 months on average) months after operation. We Analyse operation time, blood loss, postoperative hospital stay time and observe complications after UKA retrospectively. We assesse pre-and post-operative Limb alignment by HKA (hip-knee-ankle angle) and FTA (femora-tibia-angle) on full-length standing hip-to-ankle digital radiographs. We compare preoperative to the last follow-up maximum knee motion (range of motion, ROM), KSS(Knee clinical and functional Society Scores), HSS (Hospital for Special Surgery knee score) to eveluate the short term effency. We use SPSS18.0 software for data processing and statistical analysis(P<0.05 was considered statistically significant).Results38 patients were followed up for 3-14 months, average 8.8 months. The average operation time was 76.6(60-90)min. The average length of stay is 7.8 days (7-10 days) after the operation. None of patients need blood transfusion in the perioperative period.All the incisions were primary healing after operation. All patients with pain symptoms were relieved at the time of the final follow-up. NO complications such as infection, pulmonary embolism, deep venous thrombosis, iatrogenic neurovascular injuries, periprosthetic fractures, aseptic loosening, unexplained pain, insert dislocation accered after UKA. The preoperative and final follow-up HSS were 67.2+5.8 and 88.6+5.0, the knee clinical scores were 61.3±10.0 and 89.7±4.0, and the functional scores were 58.3±7.3 and 83.2±7.1. The differences between preoperative and final follow-up were statistically significant(P <0.05). The preoperative maximum range of motion of knee increased from 98.0±7.8° to 109.7±7.9° at final follow-up(p<0.05). The average HKA varied from 173.65±3.55° before surgery to 177.50±1.37° after surgery and the average FTA varied from 180.01±4.16° before surgery to 175.39±5.91° after surgery. The difference was statistically significant in the final preoperative and final follow-up (P<0.05).ConclusionThe Short-term curative effect of Minimally invasive Oxford phase 3 unicompartmental knee arthroplasty is satisfactory. The patients treated by Minimally invasive UKA has less trauma, less bone loss, shorter operation time, less blood loss, shorter postoperative hospital stay, less complications, faster postoperative recovery, greater joint mobility, and better body feeling. The axial alignment of the lower extremity is improved. However, the long-term efficacy of UKA still needs observation.