COMPARISON OF MINIMAL INCISION TOTAL HIP REPLACEMENT VERSUS STANDARD INCISION TOTAL HIP REPLACEMENT USING THE LATERAL FLARE HIP SYSTEM

Abstract

To compare the early result of minimum incision surgery (MIS) to standard incision procedures with use of lateral flare hip replacement (Revelation Hip System, DJO, USA). 38 primary total hip arthroplasty of 36 patients were performed using lateral flare hip system. Lateral flare hip has symmetric contact to medial and lateral cortical bone at high proximal part and it provides definite endpoint of stem insertion. From this point of view, we can say that this system is suitable for MIS. Among the 38 hips, 21 hips were performed by MIS (less than 10cm) and 17 hips were performed by Standard incision. MIS were performed from November 2004 to December 2005. And Standard incisions were performed from June 2004 to December 2005. Two surgeons performed all operations (NW and YT). The main surgeon decided whether MIS was applicable or not for each patient. Anterolateral intra gluteal approach (modified Dall) was applied for all surgeries. The same rehabilitation program was applied on both groups postoperatively. The average follow-up period of MIS patients was 28.6 months and 34.7 months in standard incision. We investigated the early result of these patients.

There was a relationship between patients’ height and the length of skin incision (p< 0.05). No significant difference between two groups was proved in CRP, CPK and D-Dimmer (CRP: 13.9/11.9mg/dl, CPK: 405.5/380.5mg/dl, D-Dimmer: 6.1/5.3mg/dl). Both intraoperative blood loss and operation time were less in MIS group (blood loss 530.9ml vs. 772.8ml, operation time 99min vs. 115.4min) (p< 0.05). The days until the patient was able to do active straight leg raising were 17.3 in MIS group and 22.4 in standard incision group and hospital stay days were 26.7 vs. 29.2. But no significant differences were proved in hospitalization. On roentgenografic findings, the inclination of acetabular cup was 42.0 degree in the MIS group versus 41.2 in the standard incision group and no significant difference was found. In Radiographic findings, one stable fibrous fixation was observed in each group. The other cases were bone ingrowth fixation. Japanese orthopedics association (JOA) hip score was not significant different in each group at the final follow up (88.1 in MIS group and 85.9 in Standard group). Also as the result at the term of 6, 12, 18 and 24 months after operation, JOA hip scores was not significant difference in each group. There were no revision cases in this study until the final follow up.

In the present study, intra-operative hemorrhage and operation time were significantly less in MIS group. It was supposed that at the patient selection, each surgeon decided the candidate of MIS due to patient’s hip condition. But in another situation, no significant difference was found for example in serum CRP, CPK and D-Dimmer levels. Clinical and radiological outcomes were not significantly different between MIS and Standard group in this study.