ABSTRACT
Objective To investigate the efficacy of unicompartmental knee arthroplasty(UKA) on treating elderly patients with knee osteoarthritis in comparison with total knee arthroplasty(TKA),and discuss the indications of the procedure.Methods The clinical data of elderly patients(≥75 years) undergoing UKA in our institute from October 2011 to May 2015 were retrospectively reviewed.Patients treated with UKA were in UKA group.Patients who had no significant difference in the age,gender,BMI (body mass index) and HSS (hospital for special surgery) compared with UKA group and received TKA were selected as TKA group.The outcomes were assessed by HSS and satisfaction score(range,0 ～ 10).Results A total of 29 cases (41 knees) of UKA group were followed up for (30.3 ± 13.6) months (13 ～49 months),29 cases(39 knees) of TKA group.The postoperative HSS(P =0.00),surgery time(P =0.00),perioperative hemorrhage(P =0.00),hospital stay(P =0.04) and satisfaction(P =0.03) of UKA group were all better than those of TKA group.The pain location of the knee (P =0.86) and patellofemoral degeneration (P =0.24) did not affect the postoperative outcomes,11 knees presented with varus ＞ 15° with an average angle of 18.4 ° (15.7 ° ～ 20.1 °),4 knees were with flexion contracture ＞ 15 °,averaging at 18.8 ° (17.7 ° ～ 20.1 °),range of motion measured ＜ 100° in 6 knees with an average range of 79.0° (66.8° ～ 92.1 °).The aforementioned abnormalities were effectively corrected under anesthesia,the range of motion inproved significantly,but there was no significant difference in postoperative HSS among these patients (P =0.85).One case of UKA group had wound dehiscence and superficial infection,recovery occurred after debridement and suturing.Conclusion UKA is effective for elderly patients with satisfactory outcomes,which is superior to TKA with respect to trauma control and preservation of the limb function.Medial patellofemoral degeneration poses no negative effect on postoperative outcomes,medium knee varus (≤20°) and flexion contracture(≤20°) that are corrective under anesthesia among elderly patients might not be considered as contraindications for UKA.