K. Soballe et al., MIGRATION OF HYDROXYAPATITE-COATED FEMORAL PROSTHESES - A ROENTGEN STEREOPHOTOGRAMMETRIC STUDY, Journal of bone and joint surgery. British volume, 75(5), 1993, pp. 681-687
We allocated randomly 27 patients undergoing 28 primary uncemented tot
al hip replacements (THR) to receive prosthetic components of similar
design with either plasma-sprayed titanium alloy (Ti) coating (n = 13)
or hydroxyapatite (HA) coating (n = 15). After some exclusions, 15 of
the patients (15 THR; 7 with HA- and 8 with Ti-coating) were followed
by roentgen stereophotogrammetric analysis at 3, 6 and 12 months to m
easure migration of the femoral component. Twenty-six of the patients
(26 THR) were followed clinically and by conventional radiography. All
the femoral components had migrated at 3 months. From 3 to 12 months,
the migration of Ti-coated components continued whereas the HA-coated
components had stabilised. At 12 months there was significantly less
migration of the HA-coated components (p < 0.05). The maximum subsiden
ce was 0.2 mm in both groups. The Harris hip score was equal in the tw
o groups preoperatively but at follow-up it was better in the HA-coate
d group (p < 0.05) and visual analogue scale scores showed that they h
ad less pain (p < 0.05).