867 - Scar Pain as a Cause of Atypical Facial Pain

Case Diagnosis: Common etiologies of facial pain include headaches, trigeminal neuralgia, temporomandibular disorder and herpes zoster infection. We present a case report of post surgical scar pain as an atypical cause of facial pain.

Case Description: We present a male patient in his 60s presenting with atypical facial pain worsened by chewing, yawning and swallowing in the setting of prior herpes zoster facial infection and carotid sheath surgery. He was diagnosed with post-herpetic trigeminal neuralgia and tried multiple medications (nortriptyline, pregabalin, carbamazepine, capsaicin cream, duloxetine) and interventions (TENS unit, botulinum injection to parotid, corticosteroid injection to temporomandibular joint, stellate ganglion block, superficial plexus block) without any relief. We ultimately achieved resolution of pain with methylprednisolone succinate injection to the scar in the anterior lateral neck.

Discussions: During healing, post surgical scar tissue may alter the density and distribution of local nerve fibers, causing an imbalance of excitatory to inhibitory fibers and leading to increased pain transmission. The formation of neuromas or nerve tethering may also contribute to scar pain. Corticosteroid injection into scar tissue decreases both the proliferation of fibroblasts and production of pro-inflammatory cytokines, thus discouraging scar hypertrophy and pain transmission. After failing numerous pharmacological and procedural interventions, our patient experienced complete resolution of pain after corticosteroid injection into his post surgical scar.

Conclusions: Post surgical scar pain may contribute to atypical facial pain and should be considered in patients with facial pain worsened with nonspecific jaw movements, especially if their pain is refractory to conservative management. Corticosteroid injection to the scar site may be trialed in patients with a strong clinical suspicion of scar pain.