Painful Craniofacial/Cervical Surface Area and Continuous Headache After Military Concussion: A Morphometric Retrospective Cohort Study.

Objective: In this retrospective study of active duty service members (ADSMs), possible relationships were examined between extent of headache pain depicted on head/neck diagrams and headache phenomenology.
Background: The signature injury of US military operations in Iraq and Afghanistan is mild traumatic brain injury (mTBI). Blast injury, especially from improvised explosive devices, was the most common cause during the height of the wars; the most persistent symptom remains posttraumatic headache (PTH). Neurologic patients were asked to draw pain diagrams/maps, a method of pain assessment in several clinical settings.
Methods: Thirty-four ADSMs attributing PTH to both blast and non-blast sources underwent clinical evaluations; diagnoses and headache characteristics were obtained. They completed 58 drawings depicting craniofacial/cervical headache pain on non-standardized templates. Drawings were of 29 continuous and 29 non-continuous headaches (CHA and NCHA, respectively). Surface area was calculated using a grid and expressed as a percentage.
Results: The sample was male (100%), primarily white (83%), with an average age of 30.3 years. Evidence for statistical independence of observations is provided (intra-class correlation = 0.004). Percent surface area was larger for CHA (median [mdn] = 35.2, interquartile range [IQR] = 9.0, 78.3) than NCHA (mdn = 9.1, IQR = 5.4, 34.1, P = .029). In those with blast injury, CHA percent surface areas (mdn = 45.9, IQR = 27.0, 100) were larger than NCHA (mdn = 11.6, IQR = 5.8, 28.9; P = .0012), a relationship not observed in patients with PTH from non-blasts (CHA: mdn = 26.8, IQR = 8.5, 52.0; NCHA: mdn = 9.1, IQR = 5.0, 47.6, P = .050). This pattern is observed after pooling at the median (blast, P < .012; non-blast: P = .264).
Conclusion: Painful craniofacial/cervical surface area, as shown on patient drawings, is related to PTH phenomenology (continuous versus non-continuous headache). This relationship is stronger after blast injury.
(© 2018 American Headache Society.)