Even patients with very chronic symptoms of greater trochanteric pain syndrome (GTPS) may report improvements following radial Extracorporeal Shockwave Therapy (rESWT), but no single baseline factor predicts response

Objective. Do any measures at baseline predict response from radial Extracorporeal Shockwave Therapy (rESWT) for patients with GTPS?
Methods. Setting: single UK NHS Sports Medicine Clinic. Patients: 260 patients following rESWT for GTPS. Mean age 60.0 ± 11.9 years, 81% female, mean duration of symptoms 44.5 ± 44.7 months (range: 3 months-20years). Interventions: participants received three sessions of rESWT plus structured home exercise programme (flexibility, strength, and balance). Main outcome measures: follow-up was 3-months, and 6-months. Outcome measures of self-reported “average pain”, “worst pain”, and VISA-G score. Baseline PROMS (Non-Arthritic Hip score, and Oxford Hip Score), pain (painDETECT, S-LANSS, CSI), “ability” (ODI, MSK-HQ), mood (HADS).
Results. Improvement in “average pain” of 30% at 3-months, and 37% at 6-months. VISA-G improved by more than 10% points at 3-months and 6-months. Several weak or very-weak correlations were identified, but no single baseline variable corelated strongly to the improvements seen at follow-up time-points.
Conclusions. There were clinical and statistically-significant improvements seen following rESWT for patients with GTPS, even in those with very long duration of symptoms, irrespective of age or symptom duration. There was a statistically significant difference for gender (greater benefit in female patients) which did not reach clinical significance. Greatest improvements in self-reported pain were seen in those with the worst baseline symptoms, particularly with variables more sensitive to non-arthritic hip pain (NAHS, VISA-G) than “arthritic pain” measures (OHS). Baseline measures such as Oswestry Disability Inventory or the MSK-HQ have weak correlations to improvements in some factors seen, with fewer correlations seen for markers of chronic, neuropathic, or centralised pain, or mood.