[Comparative study of total hip arthroplasty with and without femoral osteotomy in Crowe Ⅳ developmental dysplasia of the hip].

OBJECTIVE

To compare the clinical effects of total hip arthroplasty(THA) with and without femoral osteotomy in Crowe Ⅳ developmental hip dislocation(DDH).

METHODS

The data on 46 patients who underwent THA for unilateral Crowe Ⅳ DDH between 2012 and 2017 were analyzed retrospectively. They were divided into two groups according to the different surgical methods. There were 24 patients in the osteotomy group, 3 males and 21 females, with an average age of (47.3±9.0) years old ranged from 34 to 57 years old;and 22 patients in the non-osteotomy group, 2 males and 20 females, with an average age of (51.6±8.3) years old ranged from 40 to 61 years old. The operative time, bleed loss, postoperative drainage volume, postoperative complications, ROM of hip, Harris hip score, limb length discrepancy(LLD), and radiological data were recorded. The femoral dislocation height and the implantation depth of sleeve were measured.

RESULTS

All patients were followed up. The mean follow-up time was (3.8±1.2) years ranged from 2 to 6 years in the osteotomy group and (3.2±0.9) years ranged from 1 to 5 years in the non-osteotomy group. The operative time(136.8±18.9) min, bleed loss (709.8±89.4) ml, postoperative drainage volume(308.8±98.2) ml of osteotomy group were all significantly greater than those of non-osteotomy group(100.7±15.8)min, (516.5±103.3) ml, (245.3±79.3) ml (<0.05). The Harris score at the latest follow up was significantly increased compared with preoperative score in two groups (<0.05), but there was no significant difference between two groups (>0.05). The LLD at last follow up was significantly increased compared with preoperative LLD in two groups, the LLD in non-osteotomy group(0.7±0.2) cm showed signifcant smaller than the two osteotomy group(1.2±0.4) cm. Between osteotomy and non-osteotomy groups, the preoperative range of motion of hip joint [(89.5±19.7) °vs (102.5±16.8) °], the preoperative height of dislocation of femoral head [(4.56±0.61) cm vs (3.10±0.73) cm], the proximal implant depth of S-ROM [(0.93±0.36) cm vs (1.67±0.28) cm] was significantly different (<0.05). Eleven patients in the osteotomy group still had claudication, and 4 patients in the non-osteotomy group had mild claudication (<0.05). In non-osteotomy group, 3 patients developed nerve injury (1 patient of sciatic nerve, 2 patients of femoral nerve) and 1 case developed periprosthetic fracture. In osteotomy group, 2 case of dislocation and 2 cases of periprosthetic fractures.

CONCLUSION

Whether osteotomy or not can achieve satisfactory results for treating Crowe type Ⅳ DDH and significantly improve LLD. However, osteotomy is more complex and time-consuming, limb length difference is greater, and the incidence of claudication is higher. Furthermore, patients with smaller preoperative hip mobility, higher femoral dislocation, limb lengthening≥4 cm and severely narrow femoral proximal canals are prone to be peformed with subtrochanteric osteotomy.