Effect of Recombinant Human Parathyroid Hormone (1-84) on Resolution of Active Charcot Neuro-osteoarthropathy in Diabetes: A Randomized, Double-Blind, Placebo-Controlled Study

Objectives: Fractures in Charcot neuro-osteoarthropathy (CN) often fail to heal despite prolonged immobilization with below-knee casting. The aim of the study was to assess the efficacy of recombinant human parathyroid hormone (PTH) in reducing time to resolution of CN and healing of fractures.

Research Design and Methods: People with diabetes and acute (active) Charcot foot were randomized (double-blind) to either full length PTH (1-84) or placebo therapy - both in addition to below-knee casting and Calcium and Vitamin D3 supplementation. The primary outcome was resolution of CN, defined as a skin foot temperature difference below 2°C at two consecutive monthly visits.

Results: Median time to resolution was 5 months (95% CI 4, 12) in intervention and 6 months (95% CI 2, 9) in control. There was no significant difference in time to resolution between the groups (mixed effects logistic regression; p=0.64). The hazard ratio of resolution was 0.84 (95% CI 0.41, 1.74), p=0.64 and the odds ratio of resolution by 12 months was 1.22 (0.90, 1.67), p=0.20 (intervention versus control). On linear regression analysis, there were no significant differences in the effect of treatment on fracture scores quantitated on magnetic resonance imaging scans (coef= 0.13; 95% CI -0.62, 0.88; p=0.73) and on foot and ankle X-rays (coef= 0.30; 95% CI -0.03, 0.63; p=0.07).

Conclusions: This double-blind placebo-controlled trial did not reduce time to resolution or enhance fracture healing of CN. There was no added benefit of daily intervention with PTH (1-84) to below-knee casting in achieving earlier resolution of CN.