ABSTRACT:
The use of cephalomedullary devices has gained popularity in the treatment of proximal
femoral fractures. Despite their biomechanical advantages, several complications are
well described in the literature. One of these complications, which is rarely reported,
is the medial migration of the cephalic screw. The authors present this unusual complication
in a case of a long-nail implant, which was treated with removal of the implants as
a first step, and posterior osteosynthesis with a locked proximal femur plate as a
second step, as well the outcome until fracture consolidation and resolution of the
case.
Keywords: femoral fractures; fracture fixation; internal; prostheses and implants.
RESUMO:
O uso dos dispositivos cefalomedulares tem ganhado popularidade no tratamento das
fraturas do fêmur proximal. Apesar das vantagens biomecânicas, várias complicações
são descritas, entre as quais a migração medial do parafuso cefálico é pouco conhecida.
Os autores apresentam um caso dessa complicação incomum em um implante de haste longa
tratada em dois tempos cirúrgicos para a retirada dos implantes e posterior osteossíntese
com placa bloqueada para fêmur proximal, assim como o desfecho até a consolidação
da fratura e resolução do caso.
Palavras-chave: fraturas do fêmur; fixação interna de fraturas; próteses e implantes.
FIGURES
| Citation: Cavalcante Luiz Batista E, de Faria FJ, Rodrigues RA, Ribeiro Filho JEG, de Oliveira SG, Elias N. Intrapelvic Migration of the Cephalic Screw of a Proximal Femoral Long Intramedullary Nail: Case Report*. 55(01):121. doi:10.1016/j.rbo.2017.12.004 |
| Note: * Study conducted at the Orthopedics and Traumatology Service, Centro Médico Hospitalar Vila Velha (CMHVV), Vila Velha, ES, Brazil. Originally Published by Elsevier Editora Ltda. |
| Conflict of Interests: The authors have no conflict of interests to declare. |
| Received: November 10 2017; Accepted: December 07 2017 |
INTRODUCTION
Intertrochanteric fracture of the proximal femur is one of the most common fractures in patients over 65 years old, and it is often associated with osteoporosis.1
Cephalomedullary osteosynthesis is the preferred treatment for unstable fractures due to its biomechanical advantages. However, several complications are described, and the lateral and superior loosening of the femoral head screw is one of the most frequent problems, occurring in 3% to 10% of the cases.1
In turn, medial cephalic screw migration is an uncommon complication, with few cases described in the orthopedic literature, despite the high potential for morbidity and mortality.2
We describe a rare complication, the medial migration of the cephalic screw of an intramedullary Gamma 3 (Stryker, Kalamazoo, MI, US) nail, observed three months after osteosynthesis, as well as the conduction of the case until its consolidation.
CASE REPORT
A 70-year-old female patient, with hypothyroidism and osteopenia, was admitted with a history of falls from her own height. She presented pain, shortening and external rotation deformity of the right lower limb associated with inability to ambulate. Radiographs of the pelvis and right hip showed an intertrochanteric fracture (AO 31-A3) of the proximal end of the right femur (Fig. 1).
She underwent an uneventful surgical treatment, following the principle of relative stability, with indirect reduction in the skeletal traction table, and cephalomedullary osteosynthesis using a long Gamma3 130° nail, with the help of intraoperative fluoroscopy.
In the postoperative radiographic evaluation, a 26.5-mm tip-to-apex distance (TAD) was observed (Fig. 2). The patient presented favorable clinical conditions for hospital discharge on the fourth day, with prescription for home rehabilitation and partial and progressive weight bearing unloading in the right lower limb, according to tolerance. Due to the good clinical evolution, she abandoned the help of the four-support walker around the sixth week, but after three months of surgery, a sudden right hip pain started, without new trauma or fall, progressively worsening and progressing towards coxofemoral joint block after two days.
In the reassessment, we observed delayed fracture healing associated with medial migration of the cephalic screw of the nail to the pelvic region (Fig. 3), without signs of peritoneal irritation upon physical examination.
The patient was readmitted and, after five days, she underwent exploratory laparoscopy with identification of the screw in the retroperitoneal region, close to the internal iliac vessels, without evidence of damage to organs or intra-abdominal or pelvic structures (Fig. 4), which enabled the removal of the metallic implants by lateral access.
After one week, she underwent a new osteosynthesis with direct fracture reduction and fixation with principle of relative stability, with a plate locked to the proximal femur (DePuy Synthes, Raynham, MA, US) associated with cancellous bone graft from the iliac bone (Fig. 5). The patient presented a satisfactory postoperative evolution, and was discharged after four days, in good condition to restart the rehabilitation process with partial load (15% of body weight). After eight weeks, fracture healing was evidenced, which enabled movement with full load.
DISCUSSION
In the literature review, we did not identify the complication of medial migration of the cephalic screw in long-stem implants, as all reports found were associated with short femoral nails. Nor was the treatment of this complication found in association with proximal femur locked plaque.
Tauber and Resch3 reported a case of intrapelvic migration of the cephalic screw with perforation of the sigmoid portion of the intestine in a patient who subsequently underwent total hip arthroplasty (THA) cemented with a long revision femoral stem. Flint et al4 reported a case of intrapelvic migration in an 82-year-old female patient, 7 months after the fixation of an unstable pertrochanteric fracture, and a cementless THA was performed.
Heineman et al5 described the case of an 83-year-old woman who, after three weeks of fixation, presented pin migration to the pelvic region, and was submitted to a two-stage treatment: initially, removal of the implants, and later, cementless THA. Takasago et al6 presented a case of a 63-year-old woman with medial migration, 6 weeks after surgery. They also performed the review in two stages, with implant removal and subsequent THA.
Another migration report was made by Thein et al7 in a patient with five weeks of osteosynthesis, in whom the internal iliac artery was embolized by the contact evidenced on computed tomography (CT), and, afterwards, THA was performed. Li et al2 described a case of a 77-year-old woman who had a short cephalomedullary implant that was medially displaced in the 10th postoperative week. The patient underwent osteosynthesis review with placement of a shorter cephalic pin associated with a cannulated screw for anterior cancellous bone. Lucke et al8 also described two cases of medial migration treated with partial arthroplasty of the bipolar hip.
Most recently, Pinheiro et al9 described the same complication in a 92-year-old woman after 5 weeks of osteosynthesis with a short cephalomedullary nail. The patient underwent plate and sliding screw revision, evolving with a cut-out observed six months postoperatively, which was not reopened due to refusal of the patient and her relatives.
Several causes have been postulated to justify this potentially serious complication. Weil et al10 tested five cephalomedullary implants and created a biomechanical simulation model. They identified that certain conditions would need to be present to achieve medial migration, such as lateral support deficiency and unstable medial cortex, constant friction within the femoral head, and varus axial load. They also suggest that the phenomenon seems to present a higher risk of occurring in unstable fractures. Other possible causes also reported in the literature are cephalic screw misplacement, improper insertion of the anti-rotation locking device, increased TAD, femoral head damage by repetitive milling, and avascular necrosis of the femoral head.6
Medial migration of the cephalic screw is an uncommon complication in the orthopedic literature, without description of reported cases associating it with the long cephalomedullary nail or with the treatment with proximal femur locking plate.
REFERENCES
