An Early Report of the Use of a Modular Dual Mobility Articulation in Revision Acetabular Reconstruction.
BACKGROUND
Instability remains one of the main problems after revision hip surgery. The aim of this study was to review the clinical, radiological, and patient-reported outcomes with the use of modular dual-mobility articulation for revision acetabular reconstruction and investigate the risk of fretting corrosion by measuring serum trace metal ion levels.


METHODS
Sixty consecutive patients with a minimum of 24-month follow-up after the insertion of a modular dual-mobility (Stryker, Mahwah, NJ) cup at the time of revision hip surgery were identified. Follow-up included clinical and radiological patient review and functional outcome measures, and a subset of patients had their metal ion (cobalt and chromium) levels checked.


RESULTS
At the most recent follow-up, 5 patients had died, 3 patients have been revised because of ongoing instability, and 3 patients have had revision surgery due to infection. Overall functional outcome (mean Western Ontario and McMaster Universities Osteoarthritis Indexfunction 76, University of California, Los Angeles 5.6, mean Oxford 74.7, Short Form-12 physical 41.6/mental 53.3) and overall pain relief (mean Western Ontario and McMaster Universities Osteoarthritis Index pain score 78.3) scores were good. The mean satisfaction score was 78 of 100. The median serum trace metal chromium and cobalt levels at the most recent follow-up were 0.4 µg/L (range 0.1-6.1 µg/L) and 0.42 µg/L (range 0.21-9.42 µg/L), respectively. The survival with revision as the end point was 90%.


CONCLUSIONS
Dual-mobility cups with modularity represent an excellent option for the patient having revision hip surgery at high risk of instability. This series presents good patient-reported outcome measures and a low complication and revision rate.
['Diamond|Owen J|OJ|', 'Konan|Sujith|S|', 'Greidanus|Nelson V|NV|', 'Garbuz|Donald S|DS|', 'Duncan|Clive P|CP|', 'Masri|Bassam S|BS|']
D000077:Acetabulum D000328:Adult D000368:Aged D000369:Aged, 80 and over D019644:Arthroplasty, Replacement, Hip D002857:Chromium D003035:Cobalt D003343:Corrosion D005260:Female D005500:Follow-Up Studies D006622:Hip Prosthesis D006801:Humans D007477:Ions D008137:Longitudinal Studies D008297:Male D008670:Metals D008875:Middle Aged D010003:Osteoarthritis D011474:Prosthesis Design D016059:Range of Motion, Articular D012086:Reoperation D015203:Reproducibility of Results D012720:Severity of Illness Index D016896:Treatment Outcome
modular dual mobility instability metal ion levels functional outcome acetabular component revision hip arthroplasty