What has changed in total hip arthroplasty in patients of juvenile idiopathic arthritis since 2000? A systematic review and pooled data analysis.

PURPOSE: The prevalence of juvenile idiopathic arthritis (JIA) is estimated to be 16-150 per 100,000 children worldwide. The hip joint may be involved in over 50% of children leading to significant morbidity which may require surgical intervention in the form of arthroplasty. The literature lacks a concise overview of the outcomes, including complication and implant survival of total hip arthroplasty (THA) in juvenile idiopathic arthritis (JIA). The aim of this study is to systematically analyze the literature and report the outcomes of THA in JIA.

METHODS: Search was conducted in the online databases PubMed, Embase and Cochrane database. It included all original studies which evaluated clinical and/or radiological outcomes of THA in JIA with a minimum sample size of 5 patients and published in English. The level of evidence of the included studies was graded according to the Oxford Centre for Evidence Based Medicine. The Institute of Health Economics checklist was used to assess the quality of the studies included.

RESULTS: The nine studies included were retrospective in nature with all being Level IV according to Oxford Centre for Evidence Based Medicine. 475 hips in 304 patients with majority of them being females (241/304, 79.2%) were included in this review. All the studies reported the outcome objectively using various scores. The proportion of revision surgeries (92/378), either femoral or acetabular, noted was 22% (95% CI 10-33%). The proportion of acetabular revisions (72/378) was 16% (95% CI 8-25%) as compared to 4% (95% CI 1-6%) for femoral revisions (20/378). There was no difference in survivorship when cemented and uncemented implants were compared.

CONCLUSION: JIA patients with advanced hip disease represent a unique population with need for extra-long implant longevity. THA in patients of JIA leads to improved pain relief as well as mobility but the conversion of the same outcomes to functional activity is not proportionally improved. The current trend is the use of uncemented and ceramic-on-ceramic implants. Acetabular implants require earlier revision as compared to femoral implants. Age at surgery can be delayed by early institution of methotrexate which indirectly improves implant survival.

LEVEL OF EVIDENCE: IV.