Clinical values of control over pain and pain coping strategies in surgical treatment for patients with lumbar spinal stenosis.

BACKGROUND: Control over pain and pain coping strategies are associated with pain intensity as well as psychological status and subjective disability in patients experiencing pain. The present study assessed the clinical values of control over pain and pain coping strategies in surgical treatment for patients with lumbar spinal stenosis using mediation analysis.

METHODS: Sixty-two patients with lumbar spinal stenosis (median age, 70 years; 34 men, 28 women) were evaluated before surgery. The pain intensity and area, psychological status/subjective disability (Japanese Orthopaedic Association Back Pain Evaluation Questionnaire), and control over pain/pain coping strategies (Coping Strategies Questionnaire) were assessed. Mediation analysis, which consisted of serial regression analyses, mainly tested whether (1) control over pain/pain coping strategies were predicted by pain characteristics and (2) control over pain/pain coping strategies predicted psychological status/subjective disability after controlling for pain characteristics.

RESULTS: Control over pain was predicted by pain intensity (regression coefficient, -0.33; p = 0.01); moreover, it predicted walking ability (standardized partial regression coefficient, 0.31; p = 0.01) and social function (0.38; p = 0.00) after controlling for pain intensity. Although increasing activity level, one pain coping strategy, was predicted by pain intensity (regression coefficient, -0.30; p = 0.02), it did not predict walking ability (standardized partial regression coefficient, 0.07; p = 0.53) or social function (0.13; p = 0.33) when considering pain intensity.

CONCLUSIONS: In this cohort, mediation analysis demonstrated that pain intensity did not directly affect perceived walking ability or social function, but did affect control over pain; moreover, control over pain affected walking ability and social function.

CLINICAL RELEVANCE: These findings are useful for a deep understanding of the relationships between pain and subjective disability in preoperative patients with lumbar spinal stenosis. More attention should be given to patients' thoughts about pain such as control over pain.