Coexistence of pain and depression predicts poor 2-year surgery outcome among lumbar spinal stenosis patients.

BACKGROUND: Lumbar spinal stenosis is a common cause of back and leg pain with the most severe cases treated surgically. Regarding the surgery outcome, the importance of early postoperative depression and pain is unknown. AIMS: To examine whether the coexistence of pain and depressive symptoms on 3-month follow-up predicts the 2-year surgery outcome. METHODS: 93 patients (mean age 62 years) with symptomatic lumbar spinal stenosis underwent decompressive surgery. They completed the same set of questionnaires, 3 months, 1 year and 2 years postoperatively. Depression was assessed with the 21-item Beck Depression Inventory (BDI). Physical functioning and pain were assessed with the Oswestry Disability Index, the Stucki Questionnaire, self-reported walking ability, the visual analogue scale (VAS) and pain drawing. Comparisons were made between groups according to the "misery" (i.e. the coexistence of elevated pain and depression on 3-month follow-up) status. Logistic regression analysis was used to examine the factors independently associated with a poor surgery outcome on 2-year follow-up. RESULTS: The patients in the misery group (n=24) showed greater symptom severity and greater disability than the patients in the non-misery group (n=69) at all follow-up stages. No clinical improvement was seen in the misery group during the follow-up. An independent association was observed between belonging to the misery group and 2-year disability, symptom severity and poor walking capacity. CONCLUSIONS: Even moderately increased VAS and BDI scores, when presenting simultaneously on an individual patient level during the early postoperative period, imply a strong clinical burden and a risk factor for poor recovery. The assessment of pain and depressive symptoms is encouraged.

Endogenous interleukin-6 contributes to hypersensitivity to cutaneous stimuli and changes in neuropeptides associated with chronic nerve constriction in mice.

Partial nerve injury is a potential cause of distressing chronic pain for which conventional analgesic treatment with opiates or anti-inflammatory agents is not very effective. Constriction nerve injury, widely used to study neuropathic pain, was shown here to induce interleukin-6 (IL-6) mRNA in a subset of rat primary sensory neurons. When we inflicted chronic nerve constriction on mice with null mutation of the IL-6 gene, the hypersensitivity to cutaneous heat and pressure that is induced in wild-type mice was not evident, the loss of substance P in sensory neurons was excessive and the induction of galanin in central sensory projections was reduced. In additional experiments, intrathecal infusion of IL-6 in rats was shown to stimulate synthesis of galanin in approximately one-third of lumbar dorsal root ganglion neurons. The results of these experiments indicate that endogenous IL-6 mediates some of the hypersensitive responses that characterize peripheral neuropathic pain, and influences two neuropeptides that have been implicated in pain transmission.

Psychometric assessment of patients with chronic upper extremity pain attributed to workplace exposure.

Upper extremity pain attributed to workplace exposure is a growing concern in medicine today. This study was undertaken to investigate the psychological findings in patients with chronic upper extremity pain attributed to workplace exposure. Sixty-three consecutive patients were evaluated. All patients underwent a history and physical examination by a hand surgeon and a psychological evaluation by a licensed psychologist, including a Minnesota Multiphasic Personality Inventory-2 (MMPI-2). Physical and psychological findings were then compared. Forty-one patients (65%) showed abnormalities on MMPI-2 examination (t score > 70 = 97% confidence). This result is far above what generally would be expected in medical patients. When physical findings were grouped with psychological findings, 5 distinct groups were identified: 1 patient had normal physical and psychological results, 6 patients had normal physical findings but abnormal psychological assessments, 21 patients had abnormal physical findings but normal psychological assessments, 28 patients had both abnormal physical and psychological findings, and 7 patients had abnormal physical results but invalid MMPI-2 evaluations due to purposeful attempts to deny psychological symptoms. Identification of these groups may have diagnostic, prognostic, and treatment value. In addition, identification of these groups may help clarify several aspects of the debate over the role of psychosocial factors in the development and maintenance of chronic upper extremity pain that patients attribute to workplace exposure.

Pain responses in patients with upper-extremity disorders.

The purpose of this study was to evaluate the relationship between pain response factors and upper-extremity disorders associated with work-related compensable disorders. In this retrospective study, the charts of 113 patients were examined. Compensation was not found to have any statistically significant association with pain levels. The degree of functional overlay in these patients, indicated by pain questionnaire scores, differed only slightly between compensated and noncompensated patients and indicated no significant difference between the 2 groups, except that the compensated group used a higher number of descriptors to describe their pain (p = .0143). These results indicate that compensation affects the verbalization of pain but does not affect the degree of pain experienced. Working status was found to be significantly correlated with a better ability to cope with stress at home, suggesting that employment status may be a more important factor than compensation status in the presentation of these patients.

Pain, disability, and psychological functioning in chronic low back pain subgroups: myofascial versus herniated disc syndrome.

A series of patients with chronic low back pain evaluated at a tertiary referral center were the subjects for this study. Of 250 consecutive patients, 94 were diagnosed as having myofascial pain and 57 as having herniated disc syndrome. Before evaluation and diagnosis, all patients completed the McGill Pain Questionnaire, ratings of pain and disability, and the Symptom Checklist 90-R. Patients were also grouped on the basis of previous surgical history and workers' compensation benefits. Patients suffering from myofascial pain were significantly less likely to report periods of pain relief than patients with herniated disc syndrome. Those receiving workers' compensation benefits reported significantly greater levels of pain, disability, and psychological distress than those not receiving benefits, irrespective of diagnosis. Patients who underwent previous surgery did not differ significantly from those who never underwent surgery. All patients had elevated scores on the Somatization subscale of the Symptom Checklist 90-R. Patients with myofascial pain and workers' compensation benefits demonstrated the highest levels of somatization and phobia. These findings suggest that the effects of low back pain of myofascial origin have comparable, if not worse, consequences than disc herniation. These findings also reaffirm the importance of workers' compensation in understanding the differences in patients with chronic low back pain.

The Pennsylvania Plan. An algorithm for the management of lumbar degenerative disc disease.

An algorithm for the sequential management of the patient with low-back pain has been formulated from evaluation of treatment outcomes. Patients presenting with back pain complaints and cauda equina syndrome are evaluated with immediate myelography. Without this complication, back pain patients are treated with 6 weeks of conservative therapy. Those who fail to respond are evaluated with progressively more complex techniques. When sciatica predominates, treatment may ultimately include laminectomy. When back pain predominates, medical and psychosocial appraisal are recommended. Some with normal medical and psychosocial evaluations may become candidates for spine fusion. The remaining are treated according to the findings of such appraisals. Rigorous screening is mandatory prior to any surgery.

Intercostobrachial nerve entrapment syndrome.

Five patients with intercostobrachial nerve entrapment syndrome are reported. The pain in this syndrome has three aspects: somatic stimulus, perceptual surround, and behavioral response. Each must be dealt with appropriately. The distribution of the pain, its anatomic basis, and its treatment are discussed.