Mechanical low back pain: Secular trend and intervention topics of randomized controlled trials

Purpose: To evaluate the number of published randomized controlled trials (RCTs) focusing on mechanical low back pain (MLBP) rehabilitation, the secular (i.e., long-term) trend, and the distribution of interventions studied. Methods: All included RCTs were extracted from all Cochrane systematic reviews focusing on rehabilitation therapies for MLBP, and two independent reviewers screened and analyzed the information on interventions. Results: After removal of duplicates, the data set consisted of 196 RCTs published between 1961 and 2010. The number of RCTs published increased consistently over time: 2 trials (1% of the total) were published in 1961–1970, 10 (5%) in 1971–1980, 41 (21%) in 1981–1990, 68 (35%) in 1991–2000, and 75 (38%) in 2001–2010. The intervention of interest in the majority of RCTs was exercise therapy (115/399; 29%), followed by spinal manipulation therapies (60/399; 15%). Conclusion: The number of RCTs focusing on MLBP has risen over time; of all interventions studied, exercise therapy has attracted the most research interest.