To compare and analyze the early clinical outcomes of unicompartmental knee arthroplasty with mobile and fixed platform for the treatment of single compartment osteoarthritis of knee.
From January 2013 to December 2014, 86 cases (92 knees) of knee osteoarthritis with single compartment (medial) were randomly divided into two groups. One group consisted of 42 patients, including 18 males and 24 females, underwent unicompartmental knee arthroplasty with fixed platform prosthesis; the other group consisted of 44 patients, including 20 males and 24 females, underwent unicompartmental knee arthroplasty with mobile platform prosthesis. The surgery was performed by the same group of doctors. The operation time, blood loss, ROM, KSS and HSS scores of knee joint before and after surgery were recorded and the clinical follow up was completed.
The follow-up duration of the two groups ranged from 8 to 26 months, with an average of (18.20± 4.23) months. During the follow-up period, the periprosthetic fracture was found in 1 patient in the fixed platform group 1 year after operation, and polyethylene liner dislocation was found in 1 patient in the mobile platform group. No complications such as poor wound healing, periprosthetic infection or sterile prothesis loosening were found in all cases. In the fixed platform group, the operation time was (90.05±6.59) minutes and the blood loss was (53.76±6.04) ml. In the mobile platform group, the operation time was (90.73±6.74) minutes and the blood loss was (54.34±6.27) ml. In the fixed platform group, the ROM of knee increased from preoperative (94.52±4.54) degree to postoperative (104.64±4.42) degree. In the mobile platform group, the ROM of knee increased from preoperative (95.05±4.87) degree to postoperative (105.07±4.33) degree. In the fixed platform group, the KSS score increased from preoperative 48.69±5.68 to postoperative 83.55±5.37. In the mobile platform group, the KSS score increased from preoperative 49.39±5.68 to postoperative 84.11±6.14. In the fixed platform group, the HSS score increased from preoperative 45.45±3.62 to postoperative 84.55±6.08. In the mobile platform group, the HSS score increased from preoperative 45.93±4.01 to postoperative 85.16±6.30. There was no significant difference between the two groups.
There is no significant difference in the early outcome of unicondylar prosthesis with fixed and mobile platforms in the treatment of single compartmental osteoarthritis of knee. The long-term complications and revision rates of the two prostheses need further multi center and large-sample clinical study.