膝蓋腱を使用した前十字靱帯再建術後7年で生じた膝蓋腱断裂の1例

Patellar Tendon Rupture 7 Years after Use of Its Central Third for Anterior Cruciate Ligament Reconstruction : Case Report

　抄録：膝蓋腱を使用した前十字靱帯（ACL）再建術後7年以上経って生じた膝蓋腱断裂の1例を経験した．症例は41歳女性，バイク事故で左膝ACL損傷を受傷し，他院にて中1/3膝蓋腱を使用したMarshall法によるACL再建術を施行された．再建術後経過は良好だったが，7年9カ月後バレーボールの試合中に膝蓋腱断裂を受傷した．術中膝蓋腱断裂部近辺は脆弱で変性しており，デブリドマンの後一次的に縫合した．術後経過は良好で現在日常生活上特に支障はない．Marshall/MacIntosh法やBTB法のように膝蓋腱を使用したACL再建術の術後合併症の一つに膝蓋腱断裂がある．この合併症の多くは1年以内に外傷に伴って生じる急性期断裂であるが，再建術後数年経って生じる陳旧期断裂も報告されている．本症例は41歳で加齢による靱帯の変性に加え移植片採取後の阻血性変性も関与している可能性がある．

　We present a case of patellar tendon rupture 7 years after use of its central third for anterior cruciate ligament reconstruction. A 41-year-old woman sustained ACL rupture by motorcycle accident and underwent ACL reconstruction with a central third of the patellar tendon through Marshall procedure. 7 years and nine months after the surgery she sustained patellar tendon rupture while playing volleyball. The tendon was weak and degenerative, and repaired primarily after débridement. Postonerative corse is uneventful.

　Patellar tendon ruptures following ACL reconstruction with its central third have been frequently reported, mostly as an early postoperative complication resulted from traumatic events less than a year after the surgery. We describe a case of late rupture, and in this case of a 41-year-old female, it migth be possible that avascular degeneration secondary to graft havesting could be involved in trendon rupture in addition to tendon degeneration because of aging.