Sensitivity for palpating lumbopelvic soft- tissues and bony landmarks and its associated factors: A single-blinded diagnostic accuracy study

BACKGROUND: Evidence on the diagnostic performance of palpatory methods and possible confounding factors is scarce. OBJECTIVES: To examine the sensitivity of palpatory methods for location of lumbopelvic landmarks and to assess its association with personal characteristics. METHODS: Eighty-three participants (41 men, 55.6 (16.5) years, 25.9 (4.8) kg/m2 [mean (SD)]) were enrolled in this single-blinded study. Fourteen body and softy-tissue landmarks were sequentially palpated from the spinous process of L4 to the ischial tuberosity. CT-scan images were used to assess what landmark was located. RESULTS: Sensitivity for location was in range 22-86% for soft-tissues and 26-69% for bony landmarks. Reduction in sensitivity was observed from the quadratus lumborum to the inferior and lateral angle of the sacrum (86-26% and 75-33%, left and right sides, respectively). Palpations of L4 and L5 spinous processes were systematically more cephalic than other landmarks. Gender was weakly correlated to almost all landmarks (rp⁢b= 0.333 or weaker). Body mass index was weakly correlated to the accurate location of ILAS and quadratus lumborum, great trochanter, PSIS, and piriformis (rp⁢b=-0.307 or weaker). CONCLUSIONS: Systematic and propagation errors were present using sequential palpatory methods. Palpation in men was more sensitive and higher BMI was associated with lower sensitivity for lumbopelvic landmarks.