Introduction: There has been a general belief in the negative effects of increased body mass index (BMI) on the outcome of arthroplasty surgery. This study compares the complications following primary total hip replacement in obese patients.

Methods: The incidence of myocardial infarction, deep vein thrombosis, pulmonary embolism, wound infection and dislocation within the 30 days postoperative period was reviewed and compared if the BMI exceeded 30. A total of 329 patients were included in this study. There were 216 cases with BMI less than 30 compared with 113 cases of BMI more than 30. Uncemented pinnacle press-fit cup on S-ROM stem was used with 28 mm head in 137 and 36 mm head in 192 cases.

Results: There was no significant statistical difference in the incidence of early complications. However, in the subgroup of 28 mm head, there was significant increase in the infection rate when BMI was more than 30 (P< 0.032).

Discussion: In this small study, there was no significant increase in the overall incidence of the postoperative complications in obese patients. Further studies are required to assess if implant longevity is reduced in overweight patients.

Introduction: Revision total hip replacement has high rates of failure which appears to be due, in part, to deficient bone stock that does not provide an adequate environment for fixation of the implant. Cementless modular implant offers the possibility of restoration of bone stock in conjunction with adequate fixation, thus re-establishing the function of the hip without the use of additional cement. This study reviews patients treated with the S-ROM system, assessing clinical outcomes, implant stability and osseous response to the hip revisions.

Methods: Sixty two cementless revision hip arthroplasties were performed using the S-ROM prosthesis between 1996 and 2001. Fifty four were available for follow up evaluation at 3 to 8 years (median 4.5 years). Radiological analysis, patient satisfaction and Harris hip scores were assessed pre and post operatively then at average of 4.5 years later.

Results: Eighty-five percent of patients were satisfied with the result of surgery. Clinical scores improved from a preoperative value 34 to 80 points post-operatively and were maintained on further assessment at average of 4.5 years. Forty-three stems had solid bony ingrowth, nine had mild subsidence initially averaged 6.4 mm then stabilized. Two had marked initial subsidence, which also later stabilised. There was gradual filling of the osteolytic defects in 32 of the 37 (86.5%) femoral lesions.

Discussion: With improvement of the postoperative hip score by more than 50 points and absence of definite implant instability at the final follow up, the results of use of S-ROM prosthesis in the revision cases of this study seems to be successful. The follow up is relatively short, but the experience derived from this work confirms the versatility of the S-ROM prosthesis in the complex hip revision situations as well as its favourable mechanical and biologic impact on the adjacent osseous structures.