Herpes zoster rash illustrating dorsal ramus innervation in the C6 and C8 dermatomes: a report of two cases

Background: Unilateral scapular pain associated with cervical radiculopathy is frequently observed before the onset of pain in the upper extremity; but the underlying mechanism remains unclear. To better elucidate the cause of this scapular pain, we present two cases of herpes zoster with simultaneous skin rash in both the upper extremity and suprascapular or scapular region, which correspond to the painful scapular region in case of C6 or C8 cervical radiculopathy, respectively. Case Description: Case 1: a middle-aged man was observed to have a blistering herpes zoster skin rash on both the radial side of his upper extremity and the suprascapular region on the left side, which corresponded to the innervation area of the left C6 spinal nerve. Case 2: an elderly man observed a blistering herpes zoster skin rash on both the ulnar side of his upper extremity and scapular region on the right side, which corresponds to the innervation area of the right C8 spinal nerve. Conclusions: We propose that simultaneous herpes zoster rash provides a valuable model for detailing cervical dorsal ramus innervation. This may support the hypothesis that pathological conditions occluding the cervical foramen, which involve the dorsal ramus, can cause neurological scapular pain.