Age at Arthroplasty, Disease Duration Increased With Time in Patients With Juvenile Idiopathic Arthritis

Black nurse talking to boy in hospital bed on to surgery
Researchers evaluated the early prostheses implantation in patients with juvenile idiopathic arthritis and the factors affecting implant survival.

Significant increases were observed over time in age at arthroplasty and disease duration before the first arthroplasty in patients with juvenile idiopathic arthritis (JIA), according to study results published in Arthritis Care & Research. Researchers noted that JIA category, calendar year of arthroplasty, and the presence of complications were significantly associated with implant survival.

Investigators conducted a retrospective cohort study of patients with JIA who underwent total joint replacement surgery at a hospital in Milan, Italy between January 1992 and June 2019. Demographic and clinical data were extracted from patients’ medical records. Patients were followed up from their arthroplasty for implant survival, complications, and/or revision surgeries. The primary aim of the study was to describe trends in arthroplasty. Implant survival was calculated using the Kaplan-Meier method; predictors of survival were identified using Cox regression models.

Between 1992 and 2019, a total of 198 arthroplasties were observed in 85 patients (65% women). Median age at first prosthesis was 22.7 years and median disease duration before the first implant was 17.4 years. The most represented JIA categories were polyarticular and systemic JIA. No significant differences in age at arthroplasty, disease duration before surgery, number of implants, and rate of complications were observed between JIA categories. The most frequently replaced joint was the hip, followed by the knee and ankle.

Compared with patients who underwent surgery before 2000, patients treated after 2010 were significantly older (mean ages, 21.93 vs 27.81 years, respectively). Similarly, mean disease duration before arthroplasty increased from 16.98 to 22.93 years. Rates of implant survival at 5, 10, and 15 years ranged from 84% to 89%, with 52% of implants lasting for ≥20 years. Compared with patients with polyarticular JIA, those with systemic JIA had lower survival rates at 10, 15, and 20 years (P <.001). According to multivariate analysis, the year of surgery was significantly associated with implant survival (hazard ratio [HR], 1.0004; 95% CI, 1.0002-1.0006; P <.001). The absence of complications predicted greater survival (HR, 3.69; 95% CI, 1.82-7.48; P <.001).

Between 1992 and 2019, significant upward trends were observed in age at arthroplasty and disease duration before arthroplasty in a cohort of patients with JIA. Procedure year, complications, and JIA subtype were each significantly associated with implant survival.

As study limitations, investigators noted the lack of data on implant functionality and health-related quality of life, as implant survival alone may have be an insufficient measure of arthroplasty experience. The upward trend in age at arthroplasty could have reflected the increased efficacy of other medical treatments, such as disease-modifying antirheumatic drugs.

“The progressive improvement of medical treatment will lower the need for total joint replacement. Future researches should assess functional outcome and survival of implants in relation to medical therapy and different surgical approaches,” the investigators wrote.


Marino A, Pontikaki I, Truzzi M, et al. Early joint replacement in juvenile idiopathic arthritis (JIA): trend over time and factors influencing implant survival [published online May 31, 2020]. Arthritis Care Res (Hoboken). doi:10.1002/acr.24337