Outcomes of primary total hip arthroplasty in patients with Ehlers Danlos Syndromes.

Background: The Ehlers Danlos Syndromes (EDS) are inherited in an autosomal dominant pattern and patients classically present with hypermobility, skin hyper-elasticity, blood vessel fragility and atrophic scarring. Due to hypermobility, disorders such as joint pain and early arthritis are common. The aim of this study was to assess clinical and radiological outcomes of total hip arthroplasty (THA) in patients with EDS treated in a high volume orthopaedic centre.

Methods: A search was performed of the electronic patient record system at our institution from 1998 - 2019 using the search terms 'EDS' or 'Danlos' and 'arthroplasty'. Over the 22-year study period, there were approximately 32,000 primary THAs performed at our institution. We collated demographic information including age, gender, BMI, smoking history and medical comorbidities. Implant type, bearing surfaces and size was also documented, with clinical and radiological assessment at last known follow up.

Results: A total of n=5 primary THAs were identified in n=4 patients at a median follow-up of 3 years. All patients were female with a median age of 68 (SD 18.9) years and a median BMI of 30.7 (SD 4.5). The majority of patients were smokers, and had a chronic history of low back pain (n=3, 75%). Uncemented implants were used on n=3 occasions with the remainder being hybrid (n=2). Femoral head size ranged from 28mm to 44mm. One patient had a post-operative surgical wound erythema that resolved within 48 hours of onset, otherwise there were no significant wound complications. To date, there have been no documented dislocations, with all patients having satisfactory clinical and radiological outcome at last known follow up.

Conclusions: This study demonstrates that total hip arthroplasty can be safely performed in patients with a diagnosis of EDS, with no significant complications in the intermediate term.