Spinous process palpation using the scapular tip as a landmark vs a radiographic criterion standard

This study aimed at determining the standing spinal landmark that corresponds to the inferior tip of the scapula and determining the accuracy of experienced palpators in locating a spinous process (SP) 3 levels above and below a given SP.

The study participants were 34 asymptomatic or minimally symptomatic chiropractic students. An experienced palpator located the inferior scapular tip on each and then positioned a 2-mm lead marker about 5 cm lateral to the nearest SP. Two more markers were placed at levels intended to be 3 levels above and below the first marker placed. The locations of the scapular tip and the spinal targets were determined by comparison with a radiological criterion standard.

The standing inferior scapular tip corresponded to the T8 SP on average (SD = 0.9). Having placed the first lead marker, examiners on average overshot the upper marker by 0.26 (SD = 0.51) vertebral levels and undershot the lower marker by 0.21 (SD = 0.48) vertebral levels. The modes for the placement of the 3 markers were at T5, T8, and T11.

Approximately 68% of patients would be palpated to have their inferior scapular tips at T7, T8, or T9. An experienced palpator can quite accurately locate vertebral levels 3 above or below a given landmark. Chiropractors and other health professionals using the typical rule of thumb linking the inferior scapular tip to the standing T7 SP have likely been applying clinical interventions at spinal locations different from those intended.