Hydroxyapatite-coated hip prostheses. Early results from an international study.
A hydroxyapatite-coated hip prosthesis designed to stimulate proximal femoral stress transfer was studied in 222 patients undergoing primary total hip arthroplasty with a minimum followup of 2 years. The femoral component was a roughened titanium alloy with a 50-mu coating of hydroxyapatite applied to the proximal third. A proximal press-fit technique was applied with distal femoral over-reaming as standard procedure. The hydroxyapatite-coated acetabulum was of hemispherical design. Analysis of the clinical results showed a mean Merle D'Aubigné score of 16.7 points at 6 months and 17.4 points at 2 years. Mild residual thigh pain of unknown origin was reported in 3.6% of patients at 2 years. Radiographic evaluation showed complete acetabular and proximal femoral osseointegration without any loosening. No radiolucency or reactive line formation was observed around the hydroxyapatite-coated areas of the prostheses. Femoral bone densification occurred at the coated-uncoated transition zone (54%); 4% to 6% of cases showed cortical hypertrophy at the uncoated area of the stem. Reactive lines were seen around the distal stem in 52% of patients after 2 years. The clinical outcome was excellent, and the radiographic data pointed mainly to proximal femoral stress transfer.
Tonino
A J
AJ
Orthopaedic Department, De Wever Hospital, Heerlen, The Netherlands.
Romanini
L
L
Rossi
P
P
Borroni
M
M
Greco
F
F
Garcia-Araujo
C
C
Garcia-Dihinx
L
L
Murcia-Mazòn
A
A
Hein
W
W
Anderson
J
J
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016723:Bone Remodeling; D017886:Durapatite; D005260:Female; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D016896:Treatment Outcome
D017886:Durapatite