G44 - Other headache syndromes
G44.3 - Post-traumatic headache
G44.30 - Post-traumatic headache, unspecified
G44.301 - Post-traumatic headache, unspecified, intractable
G44.309 - Post-traumatic headache, unspecified, not intractable
G44.31 - Acute post-traumatic headache
G44.311 - Acute post-traumatic headache, intractable
G44.319 - Acute post-traumatic headache, not intractable
G44.32 - Chronic post-traumatic headache
G44.321 - Chronic post-traumatic headache, intractable
G44.329 - Chronic post-traumatic headache, not intractable