Long-term results of custom cementless-stem total hip arthroplasty performed in hip fusion.
INTRODUCTION
Due to complex anatomical considerations, results of cementless-stem total hip arthroplasty (THA) in hip fusion remain controversial compared with conventional THA. We therefore aimed to analyse 3D anatomy of the fused hip based on pre-operative computed tomography (CT) scans, functional outcomes based on the Harris Hip Score (HHS) and the Hip Disability and Osteoarthritis Outcome Score (HOOS), modifications of hip anatomy based on post-operative standardised radiography, and determine complication rate and long-term survival based on Kaplan-Meier analysis.


METHODS
We retrospectively studied 23 hips that underwent conversion of a fused hip to THA using a 3D CT scan-based custom titanium (Ti alloy hypoxyapetite (HA)-coated stem. The mean follow-up was 15 (9-22) years. Femur anteversion ranged from -29° to 80°.


RESULTS
HHS improved from 59 to 89 points and average range of motion (ROM) was 88° for flexion. Back pain decreased in 62%, and knee pain decreased in 42%. The mean post-operative leg-length discrepancy was 7.8 mm. No intra-operative complications occurred. One aseptic stem loosening for mechanical failure was observed. The Kaplan-Meier survivorship considering revision for any reasons as the end point was 95.6% [95% confidence interval (CI) 92.4-98.8] at 15 years.


CONCLUSION
Custom cementless stems may be an interesting solution to address the particular anatomical features of hip fusion at the time of THA, with an excellent survival rate at 15 years.
['Flecher|Xavier|X|', 'Ollivier|Matthieu|M|', 'Maman|Pascal|P|', 'Pesenti|Sébastien|S|', 'Parratte|Sébastien|S|', 'Argenson|Jean-Noël|JN|']
D000328:Adult D000368:Aged D001174:Arthrodesis D019644:Arthroplasty, Replacement, Hip D005260:Female D006621:Hip Joint D006622:Hip Prosthesis D006801:Humans D021621:Imaging, Three-Dimensional D053208:Kaplan-Meier Estimate D008297:Male D008875:Middle Aged D011475:Prosthesis Failure D016059:Range of Motion, Articular D012189:Retrospective Studies D014025:Titanium D014057:Tomography, X-Ray Computed D016896:Treatment Outcome
Custom Total hip arthroplasty Hip fusion Anatomy Hip arthrodesis