Lumbar Tactile Acuity in Patients With Low Back Pain and Healthy Controls: Systematic Review and Meta-Analysis.

OBJECTIVE: Diminished tactile acuity in chronic non-neuropathic pain syndromes has been attributed to central pain processing and cortical reorganization. The latter was recently targeted in clinical trials that demonstrated no clear advantages over traditional approaches for the reduction of nonspecific low back pain (LBP). The aim of this systematic review and meta-analysis was to summarize the current evidence on tactile acuity in LBP and pain-free controls.

METHODS: Six databases were independently searched by 2 researchers. Nineteen studies with either case-control, cross-sectional, or baseline lumbar tactile acuity data collected before an intervention were included in the qualitative and quantitative synthesis. All pooled analyses were based on random effects models. Risk of bias was assessed using the Downs and Black scale and selection criteria were verified independently by 2 assessors.

RESULTS: Data on patients (n=547) and controls (n=346) were summarized. Studies on patients included data on nonspecific chronic LBP only; no data on acute LBP were identified. There was a significant mean difference between patients and controls for lumbar tactile acuity including (11.74 mm; 95% confidence interval, 8.61-14.87) and excluding (9.49 mm; 95% confidence interval, 3.64-15.34) higher risk of bias studies.

DISCUSSION: A gap of knowledge regarding tactile acuity in populations with acute and chronic non-neuropathic LBP needs to be addressed in future research as this may significantly help the understanding of the causality of tactile acuity alterations.