外傷性の腋窩神経単独麻痺に対し橈骨神経移行術で再建を行った1例

Radial Nerve Transfer for Trauma-induced Isolated Axillary Nerve Palsy. Case Report

　症例は44歳の男性で，バイク乗車中に転倒し，多発外傷を受傷し救急搬送された．全身状態は改善したが，左肩外転障害，上腕外側部のしびれが改善せず持続していた．身体所見，筋電図所見，MRIから腋窩神経単独麻痺と診断し，経過観察していたが改善せず，受傷後4カ月の時点で橈骨神経移行術を施行した．最終経過観察時の術後18カ月時点では筋電図所見，三角筋の萎縮に明らかな改善を認めた．神経移行術は手術時期が問題となるが，受傷後4～6カ月までに行うべきと考えられた．

　A 44-year-old-male suffered multiple injuries in a motorbike accident and continued to complain of impaired abduction of his left shoulder and numbness the lateral aspect of his left arm two weeks after the injury.　We made a diagnosis of isolated axillary nerve palsy based on the physical EMG, and MRI findings.　When there was no still no evidence of recovery from the nerve palsy 4 months after the injury, we performed a radial nerve transfer to the axillary nerve.　EMG at the 18-month follow-up examination showed evidence of improvement, and there was obvious recovery from his deltoid muscle atrophy.　Based on the results in our own patient and previous reports, we consider 4 to 6 months after the injury to be the optimal time for nerve transfer.