Diagnosis of Achilles Insertional Tendinopathies by Algometry

Diagnosis of Achilles insertional tendinopathies (AIT) is based on pain by tendon palpation. However, there is no consensus or standard with regard to the amount of force to be used during the evaluation. Algometry is a method of measuring the pressure applied in a specific region and can be a method for determining diagnosis values.

To determine a cutoff value for pain threshold (PT) in the assessment of AIT.

This is a prospective case-control study of diagnostic accuracy, to develop a diagnostic criterion.

Forty asymptomatic individuals and forty patients with AIT, matched by age and sex, were evaluated and submitted to algometry for PT and for visual analog scale (VAS) levels with 3 kgf at the insertion of the calcaneal tendon by two different evaluators. Inter-observer reproducibility was assessed through the interclass correlation coefficient (ICC). Sensitivity and specificity calculations of PT and of VAS were calculated and plotted on a receiver operating characteristic curve.

The lowest ICC found was 0.788. With regard to the diagnosis through PT , the 4.08-kgf value showed the best relation between sensitivity and specificity (92.5% and 92.5%, respectively). Algometry values lower than 4.08 were considered positive for disease. For the diagnosis of AIT through VAS with 3 kgf, the value of 2.98 was estabilished (sensitivity of 92.5% and specificity of 97.5%).

Algometry was shown to be a simple and reliable method for diagnosing AIT. Values of PT less than 4.08 kgf were found to be predictors of the disease.