Highly cross-linked polyethelene was first introduced for use in total hip replacement in 1998. Since that time, there has been laboratory data and early and midterm follow-up documenting decreased wear and therefore lower revision rates for wear in total hip replacements utilizing crossed-linked polyethelene as a bearing surface. A recent report at the 19th annual meeting of the Association of Hip and Knee Surgeons outlined a significantly lower wear rate of highly cross-linked polyethelene when compared to conventional polyethelene used traditionally in total hip and knee replacements. This improved clinical performance remains promising and gives us hope that wear leading to failure in total hip replacements with metal-on-polyethelene bearing surfaces can be reduced with the use of both highly cross-linked polyethelene and newer second generation materials.
I am a 55 yo male with a history of right total hip arthroplasty performed in February 1993. The femeral component was the small head S Rom with Arthropore 2 acetabular component. I was pain free till very recently, with unaltered gait and restricted ROM (secondary to small diameter femoral head). My HHS is 85-91 as opposed to post op score of 95 (both self evaluation). I have recently begun to experience some mild discomfort after activity (walking 18 holes of golf, 30-45 minutes moderate to heavy use of recumbant excercise bicycle). Naturally, the orthopod that performed the procedure just retired (February). I usually had bi-annual reviews, without any evidence of failure. I haven’t had any film studies done recently, but hoping that no osteolysis has developed, and that I only require a revision of the polyethylene liner. My question is…can the femeral head size be altered during revision of the liner without having to completely revise the acetabular component? With the new generation of highly cross linked polyethylene liners, I was hoping to go a 32mm or greater head size, to recover lost ROM, and prevent recurrent impingement dislocations (seven to date, none in past three plus years). I am not interested in chromium cobalt metal to metal or ceramic to ceramic interfaces. Thanks for your assistance.
Gordon,
If no osteolysis then a cross-linked polyliner could be custom made to fit the existing cup but with head size it is dependent on the outer diameter size of the cup. An acetabular revision could be done and head size increased. Follow up x-rays will be useful.
Regards,
William Barrett