Pressure Pain Sensitivity Maps of the Neck-Shoulder Region in Breast Cancer Survivors

Objective. The aim of the present study was to report pressure pain sensitivity topographical maps of the frontal and dorsal parts of the shoulder region, and locate the pressure pain sensitive areas in breast cancer survivors compared with matched healthy control subjects. Methods. Twenty-two breast cancer survivors (BCS) and 22 matched control subjects participated. A numeric pain rating scale of the neck-shoulder area and pressure pain thresholds (PPTs) was assessed bilaterally over 28 points in the frontal and dorsal neck-shoulder area. Topographical pain sensitivity maps of the upper trapezius, pectoral, and anterior deltoid areas were computed. Results. A three-way analysis of variance was carried out to evaluate the differences in PPTs. The BCS reported spontaneous neck pain (mean +/- SD 3.6 +/- 2.8), pain in the affected shoulder (4.3 +/- 2.7), and pain in the non-affected shoulder (0.9 +/- 1.8). Additionally, the BCS exhibited bilaterally lower PPTs in all the measurement points as compared with the control subjects (P<0.05). The PPTs were lower at the superior part of the trapezius muscle (P<0.001), the musculotendinous insertion, the anterior part of the deltoid muscle (P<0.001), and the tendon of the pectoral muscle (P<0.001) as compared with the control subjects. Conclusions. The results suggest the sensitization processes in the BCS and give preliminary evidence to most sensitive areas in the superior part of the upper trapezius and musculotendinous insertion of the pectoral muscle.