Abstract
Introduction
Dual modular femoral stems for total hip arthroplasty were initially introduced to optimize joint biomechanics. These implants have been recalled due to fretting and crevice corrosion at the stem-neck interface, ultimately necessitating revision in a significant number of patients. At our institution we had experience with the Rejuvenate (Stryker, Mahwah, NJ) dual modular stem from 2009 until 2011 before it's recall in 2012. This study identifies complications encountered in patients requiring revision of this prosthesis.
Methods
We retrospectively identified all patients who had one particular dual modular stem using our registry database. All patients’ charts and imaging was reviewed using our electronic medical records and digital imaging programs. Patients’ age, gender, revision date, intraoperative and postoperative complications, need for subsequent surgery were identified.
Results
118 femoral stems were implanted in 107 patients (61 male & 46 female) with average follow up of over 3 years. 40 stems (34%) were revised in 36 patients with an average time to revision of 2.7 years. Women had a revision rate of 42% versus 28% in men for an odds ratio of 1.5. Complications were also increased overall with a predilection for women. 7 (15%) of revisions required an extended trochanteric osteotomy (ETO), and 5 (12.5%) had greater trochanter (GT) fractures. The most common complication postoperatively was dislocation in 25% of patients, 7 of which required reoperation. One patient had an infection after revision requiring 2-stage revision.
Discussion and Conclusion
Dual modular femoral stems are associated with a high early failure rate due to fretting and crevice corrosion. Women in particular are at higher risk for need for revision and have a higher complication rate during and after revision. A significant number of our patients required an ETO or had a GT fracture intraoperatively. Additionally, adverse local tissue reactions (ALTR) are shown to affect the abductor muscles and joint capsule. These two factors likely contribute to the high dislocation rate after revision. Preoperatively counsel patients on the higher complication rate and revision should be carried out carefully to prevent fracture and maximize stability of the hip.
