Amol Deshpande

Opioids Compared With Placebo or Other Treatments for Chronic Low Back Pain An Update of the Cochrane Review

Study Design. Systematic review and meta-analysis. Objective. To assess the efficacy of opioids in adults with chronic low back pain (CLBP). Summary of Background Data. Opioids for CLBP has increased dramatically. However, the benefits and risks remain unclear. Methods. We updated a 2007 Cochrane Review through October 2012 of randomized controlled trials from multiple databases. Use of noninjectable opioids in CLBP for at least 4 weeks was compared with placebo or other treatments; comparisons with different opioids were excluded. Outcomes included pain and function using standardized mean difference (SMD) or risk ratios with 95% confidence intervals (CIs), and absolute risk difference with 95% CI for adverse effects. Study quality was evaluated using Grading of Recommendations Assessment, Development, and Evaluation criteria. Results. Fifteen trials (5540 participants), including twelve new, met the criteria. Tramadol was better than placebo for pain (SMD, −0.55; 95% CI, −0.66 to −0.44) and function (SMD, −0.18; 95% CI, −0.29 to −0.07). Compared with placebo, transdermal buprenorphine decreased pain (SMD, −2.47; 95% CI, −2.69 to −2.25), but not function (SMD, −0.14; 95% CI, −0.53 to 0.25). Strong opioids (morphine, hydromorphone, oxycodone, oxymorphone, and tapentadol), were better than placebo for pain (SMD, −0.43; 95% CI, −0.52 to −0.33) and function (SMD, −0.26; 95% CI, −0.37 to −0.15). One trial demonstrated little difference with tramadol compared with celecoxib for pain relief. Two trials (272 participants) found no difference between opioids and antidepressants for pain or function. Reviewed trials had low to moderate quality, high drop-out rates, short duration, and limited interpretability of functional improvement. No serious adverse effects, risks (addiction or overdose), or complications (sleep apnea, opioid-induced hyperalgesia, hypogonadism) were reported. Conclusion. There is evidence of short-term efficacy (moderate for pain and small for function) of opioids to treat CLBP compared with placebo. The effectiveness and safety of long-term opioid therapy for treatment of CLBP remains unproven. Level of Evidence: 1

Characteristics of complex regional pain syndrome in patients referred to a tertiary pain clinic by community physicians, assessed by the Budapest clinical diagnostic criteria.

OBJECTIVE The aim of this study was to describe the characteristics of patients referred with complex regional pain syndrome (CRPS) diagnosis to a tertiary care pain center. METHOD Descriptive chart review study of all patients referred by family physicians or community specialists as having CRPS (2006-2010). Data extraction included demographics, pain ratings, and diagnosis utilizing the Budapest CRPS criteria. RESULTS The study population consisted of 54 subjects (male [M] =7, female [F] =47). Only 27.7% were classified as CRPS by the clinical expert. Four additional subjects carrying other diagnoses but found to have CRPS were added to the analysis. The non-CRPS group consisted of 39 subjects (M=8, F=31) and the CRPS group of 19 (M=2, F=17). CRPS patients were statistically significantly more likely to 1) have suffered a fracture; 2) report symptoms in each of the four symptom categories, as well as signs in three or four categories collectively; and 3) have allodynia/hyperalgesia alone or in combination (85/90%) as compared with the non-CRPS group (23/25%, respectively). The non-CRPS group was much more likely to report no symptoms or signs at all in the different symptom and sign categories. Of the 39 non-CRPS patients, 74% had other diagnosable entities (1/3 suffering from specific neuropathic pain conditions, e.g., radiculopathy, diabetic neuropathy, etc. and 2/3 from discreet musculoskeletal entities), while 18% were diagnosed with psychogenic pain disorders including conversion reaction associated with immobility or paralysis. DISCUSSION Besides fulfilling the Budapest CRPS diagnostic criteria, the most important other factor for diagnosing CRPS is the exclusion of a neuropathic, musculoskeletal, or non-biomedical condition accounting for the presentation.