Supercapsular percutaneously assisted total hip arthroplasty

Objective To investigate and discuss the short-term clinical outcomes and feasibility of the minimally invasive supercapsular percutaneously assisted total hip (SuperPATH) arthroplasty. Methods From December 2014 to July 2015, 14 cases of the minimally invasive SuperPATH-approach total hip arthroplasty were performed. There were six males and eight females with an average age of (74±6) years. Preoperative diagnosis of the patients included four cases of osteoarthritis, five cases of osteonecrosis and five cases of developmental dysplasia hip. Preoperative scores of the visual analogue scale (VAS), Harris score, Berg scale and Barthel index were recorded; operation time, blood loss, length of incisions, average hospitalization, operation related complications, radiological outcomes and the degree of pain relief and function rehabilitation postoperatively were analyzed. Variance analysis was applied for statistical analysis. Results All the patients were followed up from 12 to 19 months, (16±3) months on average. The average operation time, blood loss, length of incision and hospitalization were (101±25) min, (450±230) ml, (8.9±1.4) cm, (7.2±0.8) d. The average time of first straight leg raising postoperatively was (31±7) h. The negative rates of the Trendelenburg test at one month and three months postoperatively were 42.8% (6/14) and 100% (14/14), and the average Harris scores was (43.4±5) preoperatively, were(80.3±8.9) at postoperative 1st month, (91.6±6.7)at postoperative 3rd month, and(93.3±5.3) at the last follow-up(F=432.4, P<0.01). The average Berg scale scores was (29.7±6.7)before the surgery, and were postoperatively (13.8±3.7)on day 3, (18.2±6.0)on day 5, (39.6±4.3)at the 1st month, (49.0±6.1)at the 3rd month, and(54.5±2.7)at the last follow-up(F=152.6, P<0.01). The mean Barthel index was (57.9±8.4)before the surgery, and were postoperatively(32.1±8.5)on day 3, (48.9±10.6)on day 5, (81.5±5.9)at the 1st month, (94.2±6.5)at the 3rd month, (97.5±5.2)at the last follow-up(F=217, P<0.01). The average VAS scores was (8.0±1.3)before the surgery, and on 1 d, 3 d, 5 d, one month and three months postoperatively were (4.3±1.1)、(2.5±0.9)、(2.0±0.8)、(1.6±0.8)、(1.1±0.6)(F=62.8, P<0.01)respectively. As to the radiological outcomes, the average D-values of lower limb length and femoral offset and the average angles of acetabular abduction and anteversion were (4.6±3.1)mm, (3.2±2.2) mm, (36.0±4.9)°, (17.4±7.5)°. No periprosthetic fracture, infection, deep venous thrombosis, pulmonary embolism or nerve injury happened. Conclusion SuperPATH approach has the advantages of smaller incision, minimally invasive, muscle sparing, pain relief, fast recovery and good prosthesis location, which contributes the minimally invasive SuperPATH approach to be safe and feasible. Key words: Arthroplasty, replacement, hip; Minimally invasive surgical procedures; Joint capsule