An irreducible variant of femoral neck fracture: a minimally traumatic reduction technique.

Abstract We present 25 cases of irreducible variant femoral neck fractures that require surgical management after routine manipulative manoeuvre attempts have failed. In our study, an irreducible variant of femoral neck fractures is defined as a reduction that cannot be achieved after multiple attempts at closed reduction. This was evident radiographically, as seen in displaced–impacted femoral neck fractures when the proximal femur compacts and rotates along with the distal part, and anatomical reduction cannot be achieved with manipulative manoeuvres. Another rare situation also included is when the proximal fragment disconnects from the femur and dislocates as a ‘floating’ component, consequently resulting in failure of alignment of the distal fragment to the proximal femur. Here, we describe a technique, applied as a minimally traumatic procedure to achieve anatomic reduction in such cases. With the patient placed in supine position on the fracture table under general anaesthesia, the injury site is exposed and the procedure performed under intra-operative radiographic control. Location of the femoral artery is done first by palpation. The insertion site of the K-wires or Steinman pins on the proximal thigh is 1.5–3 cm lateral to the femoral artery. The K-wires or Steinman pins are inserted vertically into the middle 1/2–2/3 of the femoral head and more than 1 cm inferior to the sub-chondral bone of the femoral head to a depth of approximately, 1/2 diameter of the femoral head. The pins are then used as a joystick to control the movement of the proximal femur. With the help of the K-wires, surgeons can manually control the movement of the proximal femur and ensure anatomic reduction with the distal fragment using routine-closed reduction. Three cannulated screws are used to stabilise the fracture after anatomic reduction is achieved and maintained in a stable position. All cases were treated with this minimally invasive procedure and internal fixation, 25 fractures united, uneventfully, whilst two of them developed femoral head necrosis at 10 months and 4.5 years postoperatively, respectively.