烏口突起骨折を合併した鎖骨重複骨折の1例

Double Clavicular Fracture Associated with a Coracoid Fracture : Case Report

　抄録：烏口突起骨折と鎖骨近位および遠位端の重複骨折が合併した1例を経験した．症例は28歳，男性，スノーボードで転倒し左肩部の自発痛が出現した．X線像では鎖骨に近位端と遠位端の重複骨折と，烏口突起骨折を認めた．鎖骨近位端と烏口突起骨折を観血的に整復固定し，障害を遺残せず治癒した．受傷機転は，肩関節外側からの外力により鎖骨外側端骨折が生じ，烏口鎖骨靱帯を介して烏口突起骨折をきたしたと考えられた．近位端骨折は，上方の第3骨片の存在から鎖骨の過剰な挙上運動とこれを抑制する肋鎖靱帯により引き起こされたと推測した．

　We report a case of double clavicular fracture associated with a coracoid fracture. A 28-year-old man fell onto his left shoulder while snowboarding. X-rays showed a proximal displaced clavicular fracture with large third fragment, a distal angulated clavicular fracture, and a coracoid base fracture. We treated the proximal clavicular fracture and coracoid fracture surgically, and 8 weeks later the patient returned to work symptom-free.

　The mechanism of the injury was inferred to have been as follows. The distal clavicular fracture was caused by the external force on the shoulder, and the coracoid base fracture was caused by traction through the coracoclavicular ligament. The superior triangular fragment suggested that it was caused by forced elevation of the clavicle and restraint by the costoclavicular ligament.