大腿骨転子部骨折に対するMIJネイルの短期治療成績

Outcome of the “Made In Japan (MIJ) Nail” for Intertrochanteric Fractures of the Femur

　大腿骨転子部骨折に対して，ラグスクリュー回旋防止機構内蔵2本打ちshort femoral nailであるMade In Japan（MIJ）ネイルを用いて手術を行い，3カ月以上の経過観察が可能であった40例を対象とした．男性7例，女性33例で，平均年齢83.4歳，平均観察期間は4.6カ月であった．カットアウトなどの合併症なく，全例骨癒合を得た．MIJネイルの最大の特性は，骨頭にスクリュー2本を挿入した状態で遠位のラグスクリューの回旋を防止できることであり，短期成績は良好であった．

　The purpose of this prospective study was to evaluate the “Made In Japan (MIJ) nail” for intertrochanteric fractures of the femur. Forty cases (7 men, 33 women) with an intertrochanteric fracture of femur, treated by MIJ nail from June 2004 to March 2005, were investigated. The mean age was 83.4 years (range, 58-100 years). The mean follow up period was 4.6 months (range, 3-9 months). The mean operation time was 34 min (range, 15-90 min), The mean blood loss was 43 g (range, 10-110 g). All patients were complication-free, and had a complete union. Thirty-one patients maintained their activities of daily life. The MIJ nail is a short femoral nail and has a special mechanism. The mechanism is the presence of a set screw for protection against rotation of the lag screw, and it is included “in the nail”. It is thus possible to insert 2 screws in the head of femur and protect against rotation of the lag screw, simultaneously. This gave us a good outcome without complications of cut-out caused by neck rotation or the Z effect.