Posteriorly stabilised (Insall-Burstein) total condylar knee arthroplasty. A follow-up study of 157 knees

We reviewed 157 knees in 118 patients who underwent posteriorly stabilised (Insall-Burstein) knee replacement arthroplasty. Their mean age at operation was 69 years (range 47 to 85 years) and the average follow-up was 3.5 years (range 2 to 7 years). The "BASK" knee function assessment chart was utilised to evaluate the functional and clinical results. One hundred and thirty-five knees (86%) had excellent or good results, 16 knees (10%) had fair results and six (4%) had poor results. The mean postoperative BASK score was 79 points and the average postoperative knee flexion was 95 degrees (range 65 degrees to 130 degrees). Two patients had a superficial infection, one deep sepsis requiring revision arthroplasty and two mechanical loosening. Patellar impingement symptoms were present in 8% of the knees, although they were troublesome in less than half. Varus alignment of the knee and a varus tilt of the tibial component of more than 2 degrees correlated with the incidence of radiolucent lines around the tibial prosthesis. 90% of the patients were pleased or satisfied with the functional result. The total condylar knee is a safe, reliable and versatile prosthesis.