[Effect of reformative acetabular centralization technology on leg-length inequality in total hip arthroplasty]

To investigate the application value of acetabular centralization technology for correction of leg-length inequality in total hip arthroplasty (THA).

Between June 2001 and January 2012, 147 cases of abnormal acetabular center were treated. Of them, 68 cases underwent routine THA (control group), and 79 cases underwent acetabular reconstruction by fossae ovalis oriented centralized technology in THA (test group). There was no significant difference in gender, age, side, pathogeny, acetabular rotation center indexs, difference of relative and absolute leg-length, and Harris score between 2 groups before operation (P > 0.05). The hip joint function was evaluated by Harris score; the difference of relative leg-length was measured by tape; the difference of absolute leg-length and the horizontal and vertical distances of actual and true rotation center were also measured on the X-ray films by software.

The patients were followed up 8-26 months (mean, 8.3 months) in the test group, and 6-33 months (mean, 9.7 months) in the control group. Sciatic nerve injury occurred in 2 cases (1 in each group, respectively), lower extremity deep venous thrombosis in 7 cases (3 in test group and 4 in control group), and hip joint dislocation in 2 cases (control group); the other patients had no related complications. The difference of relative leg-length and Harris score in test group were significantly better than in control group (P < 0.05), and significant difference was also found when compared with preoperative one in 2 groups (P < 0.05). The horizontal and vertical distances of actual and the true rotation center in test group was significantly better than those in control group at immediate after operation on the X-ray films (P < 0.05); and significant differences were also found when compared with preoperative ones in 2 groups (P < 0.05). At 6 months after operation, the absolute leg-length difference in test group was significantly better than that in control group (P < 0.05); and significant difference was also found when compared with preoperative one in 2 groups (P < 0.05).

The fossae ovalis oriented acetabular centralized technology in THA can significantly correct abnormal hip center of rotation, thus reduce the relative and absolute leg-length inequality and improve the life quality of the patients.