Remodelling and pain after uncemented total hip replacement.
We studied 70 patients after uncemented hip replacement with the Lord prosthesis which has a relatively long, completely macrotextured stem. The mean follow up was for 9.5 years. We compared radiographs at one year after operation, at 5 years and at the last follow up. Twenty-five patients (36%) had deep or circumferential pain in the thigh. Of the 44 who were most active at 5 years those with thigh pain had less proximal cortical loss than those without (p < 0.05), most cortical bone formation distally and most often had incomplete radiolucent lines at the mid-stem level, perhaps indicating more elastic displacement of the bone relative to the prosthesis. The presence of radiolucent lines correlated with the increase in cortical width at 5 years (p < 0.01). Cortical remodelling continued after 5 years at all levels except at the tip (p < 0.01). The relative elastic displacement at the interface could cause pain and may contribute to the pattern of bone remodelling in the femur after uncemented hip replacement.
Lindgren
J U
JU
Department of Orthopaedic Surgery, Huddinge University Hospital, Sweden.
Svensson
O
O
Mathieson
E B
EB
D000368:Aged; D016009:Chi-Square Distribution; D005260:Female; D005500:Follow-Up Studies; D006622:Hip Prosthesis / Q000295:instrumentation / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D010149:Postoperative Pain / Q000000981:diagnostic imaging* / Q000503:physiopathology; D011379:Prognosis; D011474:Prosthesis Design; D011788:Quality of Life; D011859:Radiography; D016059:Range of Motion, Articular; D013997:Time Factors