Supracondylar Femur Fracture After Endoscopic Anterior Cruciate Reconstruction Using an EndoButton

Abstract

Clin J Sport Med 2006;16:428-429) S urgical reconstruction of the anterior cruciate ligamentdeficient knee has become very common, with the majority of reconstructions performed using the semitendinosusgracilis tendon autograft construct or the central third bonepatellar tendon-bone autograft construct. Although generally uncommon, complications after anterior cruciate ligament reconstruction occur, and may include fractures of the distal femur, proximal tibia, or distal patella.The case described below is the seventh femur fracture reported after ACL reconstruction, and the first associated with the use of an EndoButton (Smith + Nephew, Andover, MA) for femoral fixation. The fracture was felt to result from a lower than expected level of energy, on the basis of the patient's age, health, and bone quality, and was likely due to a stress riser created from multiple perforations through the anterolateral cortex of the femur from the femoral guide pin, in addition to the EndoButton tunnel. CASE REPORTA 22-year-old healthy male presented intoxicated after an altercation. He had an obvious deformity of his left distal femur, with associated swelling and marked pain. The patient indicated that he had poor recall of the injury because of head trauma. He thought that he had been kicked in the knee, but was unsure of the exact mechanism of injury.At the time of the initial assessment, there was a marked flexion deformity of the distal femur. The deformity was reduced and the lower extremity was placed in Bucks' traction. Radiographs revealed a fracture of the supracondylar region of the left distal femur, with evidence of an EndoButton located at the anterolateral aspect of the distal femur at the site of the fracture (Fig. 1).Five months before the fracture, the patient had undergone an ACL reconstruction. The reconstruction was performed using a quadrupled semitendinosus-gracilis autograft construct secured proximally with a closed-loop EndoButton. Review of the operative report indicated that there were no intraoperative complications, and that the femoral tunnel and EndoButton had been placed in the standard fashion. The patient's postoperative course was unremarkable, and he attained all the expected rehabilitation milestones.The radiographs demonstrated the femoral and tibial tunnels from the ACL reconstruction. The fracture seemed to pass through the exit point of the femoral EndoButton tunnel. The EndoButton itself was displaced from its expected site, located within the fracture, medial to the lateral cortex of the distal femur.Open reduction and internal fixation was performed utilizing a 4.5 mm locking condylar plate (Synthes Canada, Mississauga, Ontario). Intraoperatively, the fracture was noted to pass directly through the exit of the EndoButton tunnel. The EndoButton was found within the fracture site (Fig. 2). Traction on the EndoButton did not reveal any evidence of pistoning, suggesting in-growth into the graft within the femoral tunnel. After removal of the EndoButton, and before fracture fixation, c...

Femoral fracture following knee ligament reconstruction surgery due to an unpredictable complication of bioabsorbable screw fixation: a case report and review of literature

“…Fall and hyperextension injuryWilson et al [15]BPTB ACL reconstructionInterference screw, ? size9 months, fallSheps et al [12]Quadrupled ST-G autograft ACL reconstructionEndoloop button5 months, head injury, ? fall…”

“…In a case reported by Ternes et al [10] in 1993, the femoral tunnel used for the placement of a GORE-TEX prosthetic graft was the site of the fracture, which occurred 8 weeks following the procedure. Multiple anterolateral femoral cortex perforations were reported as the etiology for the fracture reported 7 months following a patellar tendon ACL reconstruction by Weiner et al [11] in 1996, and 5 months following quadrupled hamstring graft ACL reconstruction by Sheps et al [12] in 2006. Berg et al [13] in 1999 reported a fracture through the femoral tunnel 8 weeks after a bone—patellar tendon—bone ACL reconstruction.…”

Fratura supracondiliana do fêmur durante salto após reconstrução artroscópica do ligamento cruzado anterior

“…Foram encontrados poucos relatos semelhantes ao do presente e, dentre eles, apenas quatro casos (1,7,8) utilizaram enxerto de tendão dos flexores para reconstrução do LCA. Quanto ao local da fratura, apenas Noah et al (4) , Ternes et al (5) , Radler et al (6) e Sheps et al (8) relataram fraturas supracondilianas como complicação de reconstrução de LCA. Entretanto, dentre todos os casos descritos até o momento, apenas Sheps et al (8) descrevem caso com associação de fratura supracondiliana do fêmur e reconstrução de LCA com enxerto de tendão de flexores de perna.…”

“…Quanto ao local da fratura, apenas Noah et al (4) , Ternes et al (5) , Radler et al (6) e Sheps et al (8) relataram fraturas supracondilianas como complicação de reconstrução de LCA. Entretanto, dentre todos os casos descritos até o momento, apenas Sheps et al (8) descrevem caso com associação de fratura supracondiliana do fêmur e reconstrução de LCA com enxerto de tendão de flexores de perna. Nenhum dos casos encontrados na literatura ocorreu durante a realização de salto.…”

“…A fraqueza tende a ser da mesma magnitude para qualquer orifício que envolva menos do que 30% do diâmetro ósseo. Sheps et al (8) acrescentam que cuidados devem ser tomados no intra-operatório para não perfurar o córtex ântero-lateral distal do fêmur mais do que o necessário. Apesar de todos esses fatores, a magnitude de concentração de estresse sobre o túnel ósseo é biomecanicamente desconhecida (11) .…”