Spotlight on topographical pressure pain sensitivity maps: a review

Mechanical hyperalgesia defined as decreased pressure pain thresholds (PPTs) is commonly associated with pain. In this narrative review, we report the current state of the art within topographical pressure sensitivity maps. Such maps are based on multiple PPT assessments. The PPTs are assessed by an a priori defined grid with special focus on both spatial and temporal summation issues. The grid covers the muscle or the body region of interest using absolute or relative values determined from anatomical landmarks or anthropometric values. The collected PPTs are interpolated by Shepard or Franke and Nielson interpolation methods to create topographical pressure sensitivity maps. This new imaging technique has proven to be valuable in various disciplines including exercise physiology, neurology, physical therapy, occupational medicine, oncology, orthopedics, and sport sciences. The reviewed papers have targeted different body regions like the scalp, low back, neck-shoulder, and upper and lower extremities. The maps have delineated spatial heterogeneity in the pressure pain sensitivity underlining the different extents of pressure pain hyperalgesia in both experimentally induced and disease-associated pain conditions. Furthermore, various intervention studies have proven the utility of topographical pressure pain sensitivity maps. Topographical pressure pain sensitivity maps have contributed to revealing the efficacy of therapeutic, ergonomic, or training interventions that aim at reducing pain.