Pigmented villonodular synovitis does not influence the outcome following cementless total hip arthroplasty using ceramic-on-ceramic articulation: a case-control study with middle-term follow-up

BACKGROUND: Pigmented villonodular synovitis (PVNS) is a relatively rare, locally aggressive, and potentially recurrent synovial disease of large joints. The purpose of this study was to investigate (1) the disease recurrence rate and (2) the treatment outcomes including Harris hip scores, complications, and revision following cementless total hip arthroplasty (THA) with ceramic-on-ceramic (CoC) articulation in patients with PVNS. METHODS: Twenty-two patients (14 females and 8 males) with histologically confirmed PVNS underwent cementless THA using CoC bearings between 2000 and 2013. Three patients with less than 5-year follow-up were excluded. The mean age was 35.2 years (range, 22–58 years) with a mean follow-up of 8.6 years (range, 6.9–10.8 years). A control group was matched in a 2:1 ratio with the PVNS group for age, sex, body mass index (BMI), year of surgery, and American Society of Anesthesiologists score (ASA). Postoperative outcome variables included disease recurrence, Harris Hip Scores (HHS) at the latest follow-up, complications (dislocation, squeaking, ceramic fracture), and any-cause revision. A Kaplan-Meier implant survivorship curve with 95% confidence interval (CI) of the two groups was generated. RESULTS: No recurrence of PVNS was noted in the follow-up period. The HSS in the PVNS group was 92.6 ± 5.5, which was similar to the control group (93.4 ± 4.6, p = 0.584) at the last follow-up visit. No patients sustained dislocation, osteolysis, or any ceramic fracture within the study duration. One patient in the PVNS group had a complication of squeaking, but did not require revision. Another patient in the PVNS group underwent revision surgery due to aseptic loosening. There was no significant difference in revision rates between the two groups (p = 1.000). The implant survivorship free of any revision was 90.0% (95% CI, 73.2% to 100%) in the PVNS group and 92.5% (95% CI, 82.6% to 100%) in the control group at 10 years (p = 0.99). CONCLUSIONS: For young and active patients with end-stage PVNS of the hips, cementless THA using CoC bearing has similar functional outcome scores, a low complication rate, and similar implant survivorship compared to the control group.