Test-retest reliability of measuring pain extent in patients with temporomandibular disorders using a digital method for pain drawing analysis

Pitance, Laurent [UCL] Eve Gerard [UCL] Cayrol, Timothée [UCL] Roussel, Nathalie [UCL] Cordano Cescon Deborah Falla Marco Barbero et al.[show all]

Objectives: Pain drawings (PDs) are frequently used in the assessment of patient’s with pain and are part of the Diagnostic Criteria for Temporomandibular Disorders (DC-TMD). The PD helps the clinician to identify presence of widespread pain or other regional pain conditions. This work presents the test–retest reliability of a digital method of quantifying pain extent from five body diagrams representing different body regions : mouth, right and left head profile, front and back full body. Additionally, the association between PD variables and clinical features was explored in patients with temporomandibular disorders (TMD). Methods: Thirty-four patients with painful TMD assessed by the DC-TMD participated. Each patient shaded two consecutive PDs using a digital tablet. Pain extent, pain overlap between PDs and pain frequency map were generated. Correlations were obtained between pain extent and secondary hyperalgesia assessed by pressure pain threshold measurement on the tibialis anterior muscle (PPT) and other clinical features assessed by questionnaires including central sensitization, pain intensity, pain catastrophizing, anxiety and depression, neck disability, impact of headaches, symptoms of hyperventilation and quality of life (QOL). Results: The intraclass correlation coefficients for pain extent for the 5 PDs were very high: 0.95 (95% CI: 0.88–0.98), 0.98 (95% CI: 0.96–0.99), 0.96 (95% CI: 0.92–0.98), 0.98 (95% CI: 0.96–0.99), 0.95 (95% CI: 0.90–0.90) respectively for the mouth, right head, left head, body front and body back. The Bland Altman showed a mean difference close to zero for the 5 PDs showing good consistency for pain extent. Significant correlations were observed between pain extent and all measured clinical features except for secondary hyperalgesia and pain catastrophizing. Conclusions: Digital pain drawings are a reliable tool to quantify pain extent in people with painful TMD with pain extent being associated to a number of clinical features.