抄録
An 83-year-old woman presented with dropped head syndrome (DHS), that had been progressing during the previous 6 months. She had no history of neuromuscular diseases and, on examination, no neuromuscular abnormalities were observed except for isolated weakness of the neck extensors, mainly of the semispinalis cervicis. On the paravertebral sites of the T1-T5 spine on both sides, a total of eight points with marked tenderness were noted, four on each side. These eight points coincided with the anatomically narrow spaces through which the posterior rami emerged from their deep exits in the spine (i.e., the intervertebral foramina) to the superficial paravertebral sites, where they bifurcated into the lateral and medial branches, the latter innervating the semispinalis cervicis. Repeated local corticosteroid injections once a week on these eight tender points, with 3.3 mg Decadron (dexamethasone sodium phosphate) mixed with 20 mL of 0.5% xylocaine divided among the eight tender points, improved DHS in 3 months. This case suggests that the anatomically narrow pathway of the medial branches of the posterior rami at the upper thoracic spine could induce inflammations of the passing nerves, resulting in neck extensor weakness.
