3390 - Heel Spur Radiotherapy: Prospective Randomized Clinical Trial

Purpose/Objective(s): This study aims to optimize radiotherapy fractionation schedules for heel spurs (HSS, plantar fasciitis) through a prospective randomized open-label trial at Masaryk Memorial Cancer Institute (MMCI). Low-dose external beam radiotherapy (LD-EBRT) has anti-inflammatory effects and provides effective pain relief. The standard regimen consists of six fractions of 1 Gray (Gy) twice weekly, 6 Gy in total. This study hypothesizes that very low total doses of orthovoltage radiotherapy, delivered in a single fraction, may offer comparable pain relief. The primary objective is to determine whether single-fraction irradiation is non-inferior to fractionated therapy over a three months period in terms of pain relief. The study is motivated by operational constraints in radiotherapy practice (staff shortages, pandemic measures). All patients provided informed consent.

Materials/Methods: After enrollment, patients meeting all criteria completed SF-36, Calcaneodynia Score (CS), and visual analogue pain score (VAS). Inclusion criteria: age >40 years, unilateral painful HSS for =6 months, suitability for radiotherapy. Exclusion criteria: prior heel spur radiotherapy, corticosteroid injection within four weeks, systemic rheumatic diseases, lymphatic edema, prior trauma/surgery on the affected foot. Patients were randomized into six groups: Arm A (6 Gy/4 fractions), Arm B (3 Gy/2 fractions), Arm C (0.5 Gy/1 fraction), Arm D (1.0 Gy/1 fraction), Arm E (1.5 Gy/1 fraction), Arm F (2.0 Gy/1 fraction). Arm A serves as the control. If pain relief was inadequate, reirradiation (6 Gy/4 fractions) was performed after three months. A total of 966 patients will be enrolled.

Results: Data from 761 patients enrolled between September 2022 and February 2025 show reirradiation rates: A (34%), B (44%), C (54%), D (44%), E (50%), F (57%). Any pain relief occurred in A (58%), B (64%), C (55%), D (56%), E (56%), F (66%). Complete pain resolution at three months: A (11%), B (22%), C (13%), D (11%), E (10%), F (20%). CS score improvement (primary outcome) over three/six months: A (24.9%/34%), B (25.3%/37%), C (25.6%/35%), D (21.2%/33%), E (24.7%/37%), F (24%/31%).

Conclusion: Despite higher reirradiation rates in experimental arms, single-fraction irradiation appears viable, offering comparable pain relief at three months. No clear advantage was observed for single-fraction arms, requiring longer follow-up. Results suggest that single-fraction HSS radiotherapy may be a favorable option, reducing healthcare workload and improving cost-effectiveness. Trial registration NCT06104410. Supported by NU22-10-00479.