REPRODUCIBILITY OF EXAMINER PERFORMANCE FOR MUSCLE AND JOINT PALPATION IN THE TEMPOROMANDIBULAR SYSTEM FOLLOWING TRAINING AND CALIBRATION

The purpose of this investigation was to assess examiner ability to consistently perform specific tasks related to muscle and joint palpation. Four trained and calibrated examiners were asked 1) to deliver index finger pressures within a high (1.5-2.1 kg) and low (0.5-1.1 kg) target pressure range and 2) to precisely locate one joint palpation and four muscle sites. After passing a calibration test, the performance of the examiners was monitored during the course of a replicability study assessing the consistency of clinical findings during repeated exams for TM disorders. (1) Index finger pressure was regularly tested over a 3-month period with a hand held pressure algometer, and the reading of each trial was recorded. Data analysis showed a high proportion of trials within the pressure range (overall 89.5%). Examiner performance across target range of pressures was statistically different for success rate and mean pressure delivered. The differences in the mean finger pressure delivered by each examiner (intraexaminer variation) was low and varied from 0.12 to 0.22 kg/cm2 for the desired range of pressures. (2) Paired examiners were asked to independently and sequentially mark palpation sites over the forehead, superficial and deep masseter, anterior temporalis, and lateral capsule of the temporomandibular joint. Replicability of site locations was assessed by measuring, with a boley gauge, the distance between sites selected by the paired examiners. Except for the superficial masseter and the anterior temporalis, the paired examiners selected palpation sites within a distance of 7 mm more than 85% of the time. The mean distance between guessed palpation sites was the lowest for the forehead (3.6 mm; sd = 3.0) and the highest for the anterior temporalis (5.9 mm; sd = 3.5). Overall, this study clearly shows the. ability of trained examiners to consistently perform technical tasks critical to the replicability of manual palpation procedures.