Are pain coping strategies and neuropathic pain associated with a worse outcome after conservative treatment for Achilles tendinopathy? A prospective cohort study.

OBJECTIVES

To analyse whether (1) passive or active pain coping strategies and (2) presence of neuropathic pain component influences the change of Achilles tendinopathy (AT) symptoms over a course of 24 weeks in conservatively-treated patients.

DESIGN

Prospective cohort study.

METHODS

Patients with clinically-diagnosed chronic midportion AT were conservatively treated. At baseline, the Pain Coping Inventory (PCI) was used to determine scores of coping, which consisted of two domains, active and passive (score ranging from 0 to 1; the higher, the more active or passive). Presence of neuropathic pain (PainDETECT questionnaire, -1 to 38 points) was categorized as (a) unlikely (≤12 points), (b) unclear (13-18 points) and (c) likely (≥19 points). The symptom severity was determined with the validated Victorian Institute of Sports Assessment-Achilles (VISA-A) questionnaire (0-100) at baseline, 6, 12 and 24 weeks. We analysed the correlation between (1) PCI and (2) PainDETECT baseline scores with change in VISA-A score using an adjusted Generalized Estimating Equations model.

RESULTS

Of 80 included patients, 76 (95%) completed the 24-weeks follow-up. The mean VISA-A score (standard deviation) increased from 43 (16) points at baseline to 63 (23) points at 24 weeks. Patients had a mean (standard deviation) active coping score of 0.53 (0.13) and a passive score of 0.43 (0.10). Twelve patients (15%) had a likely neuropathic pain component. Active and passive coping mechanisms and presence of neuropathic pain did not influence the change in AT symptoms (p=0.459, p=0.478 and p=0.420, respectively).

CONCLUSIONS

Contrary to widespread belief, coping strategy and presence of neuropathic pain are not associated with a worse clinical outcome in this homogeneous group of patients with clinically diagnosed AT.