[Real-life efficacy and tolerability of methocarbamol in patients suffering from refractory muscle-related low/back pain - Results of a health care research project based on data from the German pain practice registry]

Abstract

Background: Subacute, muscle-related low/back pain (L/BP) is known to be difficult to treat and frequently requires more specific causal-oriented treatments with agents improving the increased muscle tone. Currently, only methocarbamol is approved and available for the 1st-line treatment of patients with muscle-related L/BP in Germany - however, without sufficient data on longer lasting effects (> 1 week) in elsewhere refractory patients.

Method: Noninterventional cohort study, based on anonymized routine data of the German pain practice registry; retrospective evaluation of patients with refractory L/BP, who first time received a treatment with methocarbamol between October 1st until December 31st, 2015, and who documented their response to treatment with the standardized and validated instruments of the German pain questionnaire over at least 4 weeks (n = 251 patients).

Results: During the 4-week evaluation period, patients reported a highly significant and clinically relevant improvement of pain intensity (from 53.0 ± 10.5 to 19.0 ± 10.0 mm VAS), pain-related disability in daily life (mPDI: from 42.1 ± 12.5 to 15.5 ± 10.8) and quality of life (QLIP: from 18.6 ± 6.3 to 34.0 ± 5.5; all changes p < 0.001 vs. baseline). Corresponding 50% response rates were 81.7 (n = 205), 68.5 (n = 172) und 91.6 (n = 230) %. In parallel, lumbar mobility (measured with the Schober's test) improved from 10.7 ± 0.7 to 14.7 ± 0.7 cm (p < 0,001). Overall, seven patients recorded eight minor treatment-related adverse events, which all resolved spontaneously during treatment without any specific countermeasures.

Conclusion: Under the conditions of daily life, patients with elsewhere refractory L/BP reported a significant and clinically relevant improvement of pain intensity, pain-related disability and quality of life in response to a 4-week treatment with methocarbamol.

Keywords: German pain practice registry; back pain; health care research; methocarbamol; muscle relaxant; subacute low back pain.