Effectiveness of continuous passive motion in alleviating neuropathic pain in people with spinal cord injury: a pilot study.

STUDY

DESIGN

Single-arm prospective pilot study.

OBJECTIVES

Chronic neuropathic pain (NP) following spinal cord injury (SCI) is often refractory to standard treatments. Sensorimotor activity has been proposed to counteract maladaptive plasticity associated with NP. This pilot study explored whether continuous passive motion (CPM) may have analgesic effects on chronic below-level NP in people with SCI.

SETTING

Incheon Workers' Compensation Hospital, South Korea.

METHODS

A total of 15 inpatients with chronic SCI and below-level NP underwent 10 sessions of knee CPM (60 minutes/day) over 2 weeks. Clinical assessments were performed at baseline (T1), immediately post-intervention (T2), and at a 1-week follow-up (T3). The primary outcome was below-level NP intensity measured using the Numeric Rating Scale (NRS). Secondary outcomes included the Neuropathic Pain Symptom Inventory (NPSI), Short-form McGill Pain Questionnaire (SF-MPQ), Patient Global Impression of Change score (PGIC), and Patient Health Questionnaire-9 (PHQ-9).

RESULTS

All participants completed the study without adverse events. NRS scores significantly decreased from T1 to T2 (p = 0.021). While total NPSI scores showed a decreasing trend (p = 0.067), the dysesthesia subscore demonstrated a significant improvement at follow-up compared to baseline scores (p = 0.009).

CONCLUSIONS

CPM is associated with a reduction of chronic below-level NP intensity in individuals with SCI. The significant amelioration of dysesthesia at follow-up may reflect neuroplastic changes, although, given the uncontrolled design, this remains hypothesis-generating. Larger randomized controlled trials are needed to confirm these preliminary findings and establish CPM as an adjunctive therapy to detect a clinically meaningful reduction in below-level NP intensity.

CLINICAL TRIAL REGISTRATION: Registered at the Clinical Research Information Service of the Republic of Korea (Identifier: KCT0007501).