Pitto RP*, Young SW*, Graves S**
*Department of Orthopaedic Surgery, University of Auckland, New Zealand **Australian Orthopaedic Association National Joint Replacement Registry
While total hip arthroplasty (THA) is an effective surgical procedure for the management of hip fractures and degenerative joint disease, dislocation remains a difficult complication and a leading cause of revision surgery.
The datasets of the Australian and New Zealand National Joint Replacement Registries were analyzed to determine the contemporary surgical management of recurrent THA dislocation. 120,870 primary THAs performed since 1999 were included in this study. Functional outcome was assessed using the Oxford Hip Score (OHS). In addition, 15,471 questionnaires returned at six months following primary THA in New Zealand patients were analyzed. 258 patients (1.6%) reported one or more dislocations and 58 (0.37%) underwent revision, giving a 1 to 4.5 dislocation to revision ratio in the first six months following primary THA.
Dislocation was the most frequent reason for revision (28.6%) after mechanical loosening (29.5%). 570 patients in Australia and 307 patients in New Zealand underwent revision for dislocation. Exchange of cup or head/liner was the most frequent revision procedures. 37% of patients had their head size increased. During the follow up period, 12% of patients underwent re-revision. The lowest rate of re-revision was seen in patients with both components revised (4.9%), and the highest rate in those whom the stem only was revised (14.6%). The mean OHS post revision for dislocation was 22.9, versus 23.4 for revision for other reasons and 19.0 following all primaries.
Dislocation remains a significant cause of morbidity following THA, resulting in poorer functional outcome and high re-operation rates.
“I very much enjoyed the Hip Session of the “Expert Meet Experts” Orthopaedic Meeting held in Padua on the 19 April. In particular,Iappreciatedthepaper“LessReturnonInvestment” of Mr. Ian Learmonth, and his point of view regarding the law of minimal return. Today, we need a greater effort and more scientific and financial investments to achieve further improvemment and more reliability and reproducibility of THR for young, active patients. I am sure we all agree that such efforts are important!