[Modified Swanson's hip replacement--intraoperative complications and learning curve of the procedure].

Our study aimed at analysis and presentation of intraoperative complications during total hip replacements with the use of limited posterior approach according to T.V. Swanson. Consecutive 210 hip arthroplasies (79 males, 131 females, aged 20-87 years, mean age 61 +/- 12,) were analyzed according to intraoperative complications. Left hip was operated in 117 cases, right in 93, bilateral procedure was performed in 27 cases (9 men, 18 women). Idiopathic disease occurred in 196 hips, 8 were result of rheumatoid arthritis, in 5 was of dysplastic origin and one occurred due to idiopathic necrosis of femoral head. In 120 cases concomitant arthrosis of the lumbosacral spine and the other joints of the lower limbs was recorded. Preoperative Harris Hip Score (HSS) was 30 +/- 5 points and Body Mass Index (BMI) ranged from 23 to 36. Our clinical material was divided into three equeal series of consecutive hip replacements (n = 70). Each of the series represented different intraoperative complications. In the first series five intraoperative notorious bleedings, four transient sciatic nerve palsies, two injuries to piriforimis muscle and one spiral fracture of the proximal femur were noted. In the second series no important adverse intraoperative findings occurred. In the third series two perforations of the acetabulum and one fracture of the femur were observed. Differences of frequencies of vascular and neural complications between these three series appeared statistically significant. The authors suggested that these observations represent the "learning curve" of the new surgical procedure--the first phase reflects difficulties and technical errors, the second without complications--maturity of the procedure and the third one carelessness due to having false sense of "perfection" by the operators.