Periprosthetic bone remodelling after cementless total hip replacement. A prospective comparison of two different implant designs.
In a prospective study of 14 patients undergoing total hip replacement we have used dual-energy X-ray absorptiometry (DEXA) to investigate remodelling of the bone around two different designs of cementless femoral prosthesis. The bone mineral density (BMD) was measured at 12-weekly intervals for a year. Eight patients (group A) had a stiff, collarless implant and six (group B) a flexible isoelastic implant. Patients in group A showed a decrease in BMD from 14 weeks after operation. By 12 months, the mean loss in BMD was 27%, both medially and laterally to the proximal part of the implant. Those in group B showed an overall increase in BMD which reached a mean of 12.6% on the lateral side of the distal portion of the implant. Our results support the current concepts of the effects of stem stiffness and flexibility on periprosthetic remodelling.
Ang
K C
KC
Department of Orthopaedic Surgery, National University Hospital, Singapore, Republic of Singapore.
Das De
S
S
Goh
J C
JC
Low
S L
SL
Bose
K
K
D015519:Bone Density; D016723:Bone Remodeling; D002484:Cementation; D005260:Female; D006622:Hip Prosthesis / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011474:Prosthesis Design