A Single Injection of Amniotic Suspension Allograft Is Safe and Effective for Treatment of Mild to Moderate Hip Osteoarthritis: A Prospective Study

Abstract

Purpose: The purpose of our study was to examine the effects of a commercially available amniotic suspension allograft (ASA) (ReNu, Organogenesis, Canton, MA) in a patient population with moderate osteoarthritis of the hip.

Methods: Ten patients with symptomatic hip osteoarthritis, defined as Tonnis grade 1 or 2 on radiographic examination, were prospectively enrolled. Each patient received a single image-guided injection of ASA into the hip joint. Patient-reported outcomes measures, including the 12-item International Hip Outcome Tool, Modified Harris Hip Score, and Single Assessment Numeric Evaluation scores were recorded at baseline, 6 months, and 12 months postinjection. A linear regression model was performed to detect differences in outcome scores from baseline.

Results: Nine patients had complete 12-month data available for analysis. One patient failed treatment and underwent arthroplasty at 2 months postinjection. The cohort includes 5 males and 4 females, aged 47-67. International Hip Outcome Tool scores demonstrated a significant improvement between baseline and 12 months (P = .02). Single Assessment Numeric Evaluation scores demonstrated a significant difference between baseline and 6 months (P < .01), as well as between baseline and 12 months (P < .01). Modified Harris Hip Scores demonstrated a significant difference between baseline and 6 months (P = .02) and between baseline and 12 months (P = .01). There were no major adverse events in the course of the study period.

Conclusion: This study demonstrates promising results for relief of pain and improvement in patient-reported outcomes with intra-articular ASA in patients with moderate osteoarthritis of the hip for up to one year, although the exact mechanism of action remains unknown. LEVEL OF EVIDENCE: IV, case series.