Objective documentation of musculoskeletal pain syndrome by pressure algometry during thiopentone sodium (Pentothal)...

Work and injury related musculoskeletal pain is often complicated by psychological and medicolegal factors that obscure the validity of the pain presentation. Pressure algometry and stretching during thiopentone sodium (Pentothal) anesthesia was studied in 45 cases of musculoskeletal injury. A total of 40 cases were determined as genuine, organic pain, four cases were negative (i.e., nonorganic pain), and one case was equivocal. In unilateral pain cases, a right to left pressure threshold difference of 2.0 kg/cm2 predicted 94% of true organic pain cases and 100% of cases at a pressure threshold of 1.5 kg/cm2 if combined with stretching. Results of stretching painful areas correlated highly with pressure threshold assessments.