Abstract
Goal
The goal of this prospective, non-randomized study is to compare functional and life-quality changes in primary total hip replacement (THR) with minimally invasive anterior (MIA) and direct lateral (DL) approach in six months follow-up.
Materials and Methods
Sixty (30 MIA and 30 DL) consecutive patients underwent primary THR were operated by the same senior surgeon. Patients completed functional and life-quality scores (Oxford Hip Score, Harris Hip Score, EQ-5D) before operation and four times (2 and 6 weeks, 3 and 6 months) after THR. Physical examination was taken all times. 15–15 patients underwent MRI examination to adjudge status of abductor muscles. The average patient age was approximately equal in both group.
Results
The average OHS values were 13,4; 27,5; 40,9; 45,3; 47,5 in MIA and 15,3; 25,3; 39,7; 43,8; 45 in DL, the average HHS values 43,1; 68,7; 85,3; 91,9; 96,7 in MIA and 43; 58,2; 81,5; 90,2; 93,9 in DL, the average EQ-VAS 41,1; 72,5; 85,9; 87,8; 92,4 in MIA and 55,6; 67,8; 80,6; 84; 91,3 in DL consecutively. In MIA group both functional and life-quality scores showed better results, but for the 3rd postoperative month increases were approximately equal. Abductor muscle strength was significantly greater in MIA group in this period. In the 6th postoperative week Trendelenburg-sign was detected in 24 cases (80%) in DL and in 2 cases (6,7%) in MIA group, but in MIA patients were greater trochanter fractures, which had gone healing and limping was not detected 3 months after surgery. 3 months after surgery Trendelenburg-sign was detected in 2 cases in DL group. In follow-up period residual trochanteric pain was detected in 3 cases in DL but none in MIA group. Two weeks after THR climbing a flight of stairs was normal and public transport could be used by 80% of patients in MIA group. Distance walk was unlimited, support had not needed, daily activities were easy.
There were 7 operative complications in MIA group, including 2 greater trochanter fracture, 1 haematoma and 4 transient lateral femoral cutaneous nerve palsy, which showed change for the better after 6 months. Postoperative hip dislocation was not detected.
In DL group MRI represented fatty infiltration and atrophy of abductor muscles in most cases.
Conclusions
Besides the fact that our learning curve may influence the results. It seems that earlier mobilisation and faster postoperative recovery can be achieved by MIA approach, which have many financial and social benefits. It preserves muscles and tendons, which probably can influence the long-term results. By preventing abductor muscles can assure better gait pattern. Of course additional long-term studies are needed.
