Algometry in the daily practice of pain management

This is a review article to update the clinical applications of pressure pain sensitivity (PPS) measurement by pressure algometry (PA) [1,2].

The basic literature on pressure algometry has been reviewed with emphasis on new developments. The author's and his co-workers' experience with PA, extending several years, are also included along with some unpublished research results.

The high reliability and validity of PA for quantification of PPS has been proven by several authors. The specificity and sensitivity of PA in detection of trigger points (TrPs) is also very good. PA is also useful in evaluation of treatment results. PA can document the decreased PPS after 'preinjection (regional) blocks' administered prior to trigger point injections (TPIs). A study of ten patients with failed back surgery included 20 muscles. PA documented long-term improvement (150 days) which corresponded to a decrease in pain rating. Treatment consisted of needling and infiltration of the entire trigger point (TrP) extending to taut band. Another study showed that physicians were unable to produce 4 kg of pressure, which is critical for diagnosis of fibromyalgia.

Quantification of fibromyalgia diagnosis by PA is necessary for abnormal tenderness (pain on 4 kg pressure). The critical pressure for TrP, tender spots is a pressure pain threshold lower by 2 kg/cm2 relative to a normally sensitive corresponding control point.