Baseline characteristics of the GTN, placebo group and all trial participants
| GTN (n=37) Mean±SD | Placebo (n=39) Mean±SD | All participants (n=76) Mean±SD | |
| Age (mean±SD years) | 44.4±9.18 | 46.7±7.19 | 45.6±8.2 |
| Number of females (%) | 16 (43) | 14 (36) | 30 (39) |
| Height (mean±SD cm) | 170.5±17.4 | 174.4±9.86 | 172.5±14.1 |
| Body mass (mean±SD kg) | 81.4±13.97 | 82.2±14.84 | 81.78±14.3 |
| BMI (mean±SD kg/m2) | 27.2±3.98 | 27.0±4.29 | 27.1±4.1 |
| Duration of symptoms (mean±SD months) | 37±51.9 | 29±41.58 | 33±46.8 |
| Number with unilateral symptoms (bilateral symptoms) | 29 (8) | 25 (14) | 54 (22) |
| Activity per week, before injury (mean±SD days/week) | 5.5±2.21 | 5.3±1.94 | 5.4±2.1 |
| Activity per week, before injury (mean±SD min/week) | 330±165.84 | 349±168.87 | 340±166.5 |
| Comorbidities, number of participants (%) | |||
| HTN | 5 (14) | 2 (5) | 7 (9) |
| Hypercholesterolaemia | 4 (11) | 2 (5) | 6 (8) |
| Type II DM | 0 (0) | 1 (3) | 1 (1) |
| Smoking | 1 (3) | 0 (0) | 1 (1) |
| Ethnicity, number of participants (%) | |||
| Caucasian | 36 (97) | 39 (100) | 75 (99) |
| Afro-Caribbean | 1 (3) | 0 (0) | 1 (1) |
| Asian | 0 (0) | 0 (0) | 0 (0) |
| Other | 0 (0) | 0 (0) | 0 (0) |
| Previous treatment, no. of participants (%) | |||
| CSI>3 months before recruitment | 1 (3) | 2 (5) | 3 (4) |
| HVI | 0 (0) | 1 (3) | 1 (1) |
| Night splint | 0 (0) | 1 (3) | 1 (1) |
| PRP | 0 (0) | 1 (3) | 1 (1) |
BMI, body mass index; CSI, corticosteroid injection; DM, diabetes mellitus; GTN, glyceryl trinitrate; HTN, hypertension; HVI, high-volume injection; PRP, platelet rich plasma injection.