Low Back Pain and Sciatica

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SCIENTIFIC ABSTRACTS

Low Back Pain and Sciatica

Percutaneous electrical nerve stimulation for low back pain: a randomized crossover study.

Ghoname EA, Craig WF, White PF, Ahmed HE, Hamza MA, Henderson BN, Gajraj NM, Huber PJ, Gatchel RJ.

Eugene McDermott Center for Pain Management, Department of Anesthesiology and Pain Management, University of Texas Southwestern Medical Center, Dallas 75235-9068, USA.

CONTEXT: Low back pain (LBP) contributes to considerable disability and lost wages in the United States. Commonly used opioid and nonopioid analgesic drugs produce adverse effects and are of limited long-term benefit in the management of this patient population. OBJECTIVE: To compare the effectiveness of a novel nonpharmacologic pain therapy, percutaneous electrical nerve stimulation (PENS), with transcutaneous electrical nerve stimulation (TENS) and flexion-extension exercise therapies in patients with long-term LBP. DESIGN: A randomized, single-blinded, sham-controlled, crossover study from March 1997 to December 1997. SETTING: An ambulatory pain management center at a university medical center. PATIENTS: Twenty-nine men and 31 women with LBP secondary to degenerative disk disease. INTERVENTIONS: Four therapeutic modalities (sham-PENS, PENS, TENS, and exercise therapies) were each administered for a period of 30 minutes 3 times a week for 3 weeks. MAIN OUTCOME MEASURES: Pretreatment and posttreatment visual analog scale (VAS) scores for pain, physical activity, and quality of sleep; daily analgesic medication usage; a global patient assessment questionnaire; and Health Status Survey Short Form (SF-36). RESULTS: PENS was significantly more effective in decreasing VAS pain scores after each treatment than sham-PENS, TENS, and exercise therapies (after-treatment mean +/- SD VAS for pain, 3.4+/-1.4 cm, 5.5+/-1.9 cm, 5.6+/-1.9 cm, and 6.4+/-1.9 cm, respectively). The average +/- SD daily oral intake of nonopioid analgesics (2.6+/-1.4 pills per day) was decreased to 1.3+/-1.0 pills per day with PENS (P<.008) compared with 2.5+/-1.1, 2.2+/-1.0, and 2.6+/-1.2 pills per day with sham-PENS, TENS, and exercise, respectively. Compared with the other 3 modalities, 91 % of the patients reported that PENS was the most effective in decreasing their LBP. The PENS therapy was also significantly more effective in improving physical activity, quality of sleep, and sense of well-being (P<.05 for each). The SF-36 survey confirmed that PENS improved posttreatment function more than sham-PENS, TENS, and exercise. CONCLUSIONS: In this sham-controlled study, PENS was more effective than TENS or exercise therapy in providing short-term pain relief and improved physical function in patients with long-term LBP.

JAMA 1999 Mar 3;281(9):818-23

Percutaneous electrical nerve stimulation: an alternative to TENS in the management of sciatica.

Ghoname EA, White PF, Ahmed HE, Hamza MA, Craig WF, Noe CE.

McDermott Center for Pain Management, Department of Anesthesiology and Pain Management, University of Texas Southwestern Medical Center at Dallas, Dallas, USA.

Sciatica is a common pain problem and current pharmacologic therapies have proven inadequate for many patients. The objective of this sham-controlled investigation was to compare a novel non-pharmacologic technique, percutaneous electrical nerve stimulation (PENS), to transcutaneous electrical nerve stimulation (TENS) in the management of the radicular pain associated with sciatica. Sixty-four consenting patients with sciatica due to lumbar disc herniation were treated with PENS, TENS and sham-PENS according to a randomized, single-blinded, cross-over study. All patients had been maintained on a stable oral non-opioid analgesic regimen for at least 6 weeks prior to entering the study. Each treatment modality was administered for a period of 30 min three times per week for 3 weeks, with 1 week 'off' between each modality. Both PENS and TENS treatments were administered using a stimulation frequency of 4 Hz. The pre-treatment assessment included the health status survey short form (SF-36), as well as visual analog scales (VAS) for radicular pain, physical activity and quality of sleep. The pain VAS was also repeated after each treatment session. At the end of each 3-week treatment block, the SF-36 was repeated. After receiving all three treatment modalities, a global assessment questionnaire was completed. Both PENS (42%) and TENS (23%) were significantly more effective than the sham (8%) treatments in decreasing VAS pain scores. The daily oral analgesic requirements were also significantly reduced compared to the pre-treatment values with PENS (P<0.01) and TENS (P<0.05). However, PENS was significantly more effective than TENS (and sham-PENS) in improving physical activity and quality of sleep. The SF-36 evaluation confirmed the superiority of PENS (versus TENS and sham-PENS) with respect to post-treatment functionality. In the overall assessment, 73% of the patients reported that PENS was the most desirable modality (versus 21% for TENS and 6% for sham-PENS). Finally, 71% of the patients stated that they would be willing to pay extra to receive PENS therapy compared to 22% and 3% for TENS and sham-PENS, respectively. In this sham-controlled study, we concluded that PENS was more effective than TENS when administered at a stimulation frequency of 4 Hz in providing short-term pain relief and improved functionality in patients with sciatica.

Pain 1999 Nov;83(2):193-9

The effect of stimulus frequency on the analgesic response to percutaneous electrical nerve stimulation in patients with chronic low back pain.

Ghoname ES, Craig WF, White PF, Ahmed HE, Hamza MA, Gajraj NM, Vakharia AS, Noe CE.

Eugene McDermott Center for Pain Management, Department of Anesthesiology & Pain Management, University of Texas Southwestern Medical Center at Dallas, 75235-9068, USA.

Low back pain (LBP) is one of the most common medical problems in our society. Increasingly, patients are turning to nonpharmacologic analgesic therapies such as percutaneous electrical nerve stimulation (PENS). We designed this sham-controlled study to compare the effect of three different frequencies of electrical stimulation on the analgesic response to PENS therapy. Sixty-eight consenting patients with LBP secondary to degenerative lumbar disc disease were treated with PENS therapy at 4 Hz, alternating 15 Hz and 30 Hz (15/30 Hz), and 100 Hz, as well as sham-PENS (0 Hz), according to a randomized, cross-over study design. Each treatment was administered for a period of 30 min three times per week for 2 wk. The pre- and posttreatment assessments included the health status survey short form and visual analog scales for pain, physical activity, and quality of sleep. After receiving all four treatments, patients completed a global assessment questionnaire. The sham-PENS treatments failed to produce changes in the degree of pain, physical activity, sleep quality, or daily intake of oral analgesic medications. In contrast, 4-Hz, 15/30-Hz, and 100-Hz stimulation all produced significant decreases in the severity of pain, increases in physical activity, improvements in the quality of sleep, and decreases in oral analgesic requirements (P < 0.01). Of the three frequencies, 15/30 Hz was the most effective in decreasing pain, increasing physical activity, and improving the quality of sleep (P < 0.05). In the global assessment, 40% of the patients reported that 15/30 Hz was the most desirable therapy, and it was also more effective in improving the patient's sense of well-being. We conclude that the frequency of electrical stimulation is an important determinant of the analgesic response to PENS therapy. Alternating stimulation at 15-Hz and 30-Hzfrequencies was more effective than either 4 Hz or 100 Hz in improving outcome measures in patients with LBP. Implications: The frequency of electrical stimulation seems to be an important determinant of the analgesic efficacy of percutaneous electrical nerve stimulation. Mixed low- and high-frequency stimulation was more effective than either low or high frequencies alone in the treatment of patients with low back pain.

Anesth Analg 1999 Apr;88(4):841-6