Ipsilateral femur neck and shaft fractures occur due to a high-velocity injury. They are common in injuries due to road traffic accidents. The chances of a missing neck of femur fracture occurring along with a shaft fracture are high almost 19–31% [1, 2]. Non-union after femoral neck fracture can be defined as a lack of radiographic evidence of union 6 months after the fracture ^[3]. An important risk factor for developing avascular necrosis of the femoral head following a fractured neck of the femur is the displacement of fracture ^[4]. A recent meta-analysis by Konarski et al. of 5930 surgically operated cases showed no significant correlation when operated within or after 24 h after trauma ^[4]. The missed neck of femur fracture with an ipsilateral shaft femur fracture is not uncommon. In this article, we report a case of a 25-year-old male with a neglected ipsilateral neck of femur non-union along with the shaft of femur non-union which was successfully managed with subtrochanteric valgus osteotomy with impaction bone grafting for the neck of femur along with dual plating and bone grafting for the shaft of femur fracture non-union.

A 25-year-old male presented with complaints of right hip and thigh pain and swelling for the past 6 months. Previous history of falls from height 6 months back and he was treated with indigenous splinting for 6 months. He was barely ambulating with support for the past 6 months. Otherwise, the patient was healthy, non-smoker, and had no history of head injury. Clinically, the patient was unable to do SLR, with abnormal mobility over the distal femur and shortening of the right lower limb. Clinically, there are no signs of infection. The blood workup was unremarkable. X-ray showed the right neck of femur fracture non-union with the shaft of femur fracture non-union with gross over-riding of fracture fragments (Fig. 1). MRI was done which showed a viable femoral head.

Pre-operative assessment

In a standard AP with a leg in internal rotation, a horizontal line is drawn along the roof of the acetabulum perpendicular to the anatomical axis of the femur shaft. At the point of intersection of these two lines, a line is drawn along the fracture line. The angle formed between the horizontal line and the fracture line is the Pauwels angle. Pauwels angle was calculated to be 69° which denotes type 3 unstable fracture (Fig. 2). The osteotomy angle is calculated by subtracting 30° from the Pauwels angle. The guide pin insertion angle is calculated by subtracting the osteotomy angle from the angle of the barrel plate used. In our case, we planned for an osteotomy angle of 30° with a 140° barrel plate which gave us a pin insertion angle of 110°. The aim of our surgery was to convert type 3 Pauwels to type 1 Pauwels which converts shear forces into compression forces aiding in favorable biomechanical healing of neck of femur fracture.

The patient was scheduled for Stage (I) ORIF with dual plating and bone grafting for the right shaft of femur.

Stage (II) valgus subtrochanteric osteotomy with impaction bone grafting and dynamic hip screw (DHS) fixation for the right femoral neck.

Stage (I) shaft of femur open reduction through a lateral approach. All fibrous tissues were removed and bone edges curetted. With length and alignment maintained, 12-hole broad 4.5 mm DCP was used to stabilize the fracture with appropriate screws. Cancellous bone graft harvested from proximal tibia and packed at the non-union site. In addition, 7-hole 3.5 mm DCP was fixed anteriorly with two screws proximal and distally each (Fig. 3).

Stage (II) After 3 days the patient was scheduled for hip subtrochanteric valgus osteotomy and impaction bone grafting. Patient on a traction table, through lateral incision proximal femur exposed. The guide pin was inserted at the predetermined insertion angle and the derotation k wires were fixed. Triple reaming was done, and under C-arm guidance, a straight and curved curette was introduced through the reamed tunnel to remove the fibrous tissues around the non-union site without opening the non-union externally. A cancellous bone graft was harvested from the proximal tibia. PFN drill sleeve guide was used to transfer the bone graft to the non-union site. Reverse reaming is done with an inner reamer for impaction of the bone graft. Richard’s screw of 90 mm fixed.

The osteotomy site is longitudinally marked with electrocautery to asses rotational alignment and subtrochanteric osteotomy is done with the transverse cut just below the lesser trochanter 1 cm below the triple reamer entry point to prevent lateral wall fracture. Lateral-based 3 cm wedge was resected with an intact medial hinge which was later weakened with multiple drill holes. 140° 4-hole barrel plate was inserted. Traction was released and the distal fracture fragment was abducted closing the wedge. The distal fragment and the barrel plate were held with a bone-holding clamp. Screws were fixed to the barrel plate. A compression screw was applied and a derotation screw was applied completing the valgus osteotomy. The wound closed in layers with a negative suction drain.

Postoperatively, the patient was mobilized non-weight bearing and knee bending was encouraged. He was on regular follow-up and started on partial weight bearing after 2 months and full weight bearing after 3 months. Both non-union completely united in 1-year follow-up X-rays (Fig. 4). At 1-year follow-up, he was able to do good functional active hip and knee range of motion and active SLR (Fig. 5 and 6). He was able to walk without support and climb stairs up to 40 staircases. His hip ROM is flexion 0 to 100°, extension 0–10°, abduction 0–40°, adduction 0–20°, internal rotation 0–30°, external rotation 0–20°, and knee ROM was 0–110°. His hip outcome score is 84%. The patient has no residual pain in the hip or thigh.

The incidence of femoral neck fractures occurring along with shaft fractures is 2.5–6% [5, 6]. The incidence of non-union in neck fractures is 5–43% and shaft fracture is 2–10% [1, 2, 7]. As per literature neck of femur fracture is considered neglected if treatment is delayed for more than 3 weeks and considered non-union if there is no union after 6 months of surgical intervention ^[8]. An arbitrary definition of femur shaft non-union is considered 9 months of injury or no signs of bone callus formation on subsequent radiographs within 3 months. In our case, the patient presented after 6 months of injury with gross mobility of the distal femur fragment in all directions with minimal pain and poor callus formation hence was considered non-union ^[9]. The risk of non-union in the neck with shaft fractures is high due to high-velocity injury causing more vascular disruption. Most of the energy is transmitted to the femur shaft causing severe soft-tissue stripping of the shaft fragments. The neck of femur fracture is usually a low-energy trauma with a vertical fracture line. In polytrauma patients, neck fractures occurring with shaft fractures usually get missed due to its un-displaced or minimally displaced nature ^[10]. Hip salvage procedures include osteosynthesis with or without various angular/displacement osteotomies and vascularized/non-vascularized bone grafting techniques. Valgus osteotomy has shown promising results in numerous studies in the non-union neck of femur in young patients. Implant routinely used for valgus osteotomy is DHS, DCS, or angle blade plates. Valgus osteotomy done using angle blade plate fixation was described in many studies with satisfactory results [11-14]. Angle blade plate has excellent rotational control but is technically difficult. DHS being a very familiar implant is technically easier in the hands of most surgeons and provides excellent compression which aids in the healing of the non-union. The aim of valgus osteotomy is to convert the predominant shearing forces to compressive forces aiding in union. However, care must be taken not to reduce the angle to <25° as the risk of AVN increases. Muller has insisted on valgus correction of <25° for consistent results^[15]. In cases of neck resorption and shortening of the limb, valgus osteotomy can help restore the limb length discrepancy. In our case, we opted for subtrochanteric osteotomy as it will prevent intracapsular penetration of the saw/osteotomy blade. It also prevents damage to the iliopsoas insertion site which helps in preventing damage to the femoral head blood supply ^[8]. In our case, we choose to do impaction bone grafting to enhance the biology at the non-union site and it also helps in filling the small cavitary defects at the non-union site. Hartford et al. study in 2005 ^[16] and Schoenfeld and Vrabec’s study in 2006 ^[17] describe valgus osteotomy with DHS as the implant of choice. In both studies, intertrochanteric osteotomy was done. Hartford’s study uses full-thickness lateral wedge osteotomy and Schoenfeld’s study includes partial wedge osteotomy. Partial wedge osteotomy is good in restoring limb length postoperatively but has chances of non-union and implant failure due to less contact area. (Fig. 7).

Neglected fracture non-union is not an uncommon scenario in a developing country. Neglected fracture non-union involving the neck of femur with neglected shaft fracture non-union in a young patient made this a challenging case both from the technical point of view and fracture healing perspective. Salvaging the femoral head is always the priority in young patients. Valgus osteotomy with impaction bone grafting for the non-union neck of femur along with dual plating and bone grafting for the shaft of femur provides a satisfactory outcome in this complicated dual non-union in a single bone.

Valgus osteotomy is the treatment of choice for young active patients with non-union of femoral neck fractures with a viable femoral head. The union rate approaches 90% in the most reported literature. Avascular necrosis being the most common complication leading to failure and subsequent total hip arthroplasty must be clearly explained to the patient. Similarly maintaining anatomical alignment, respecting biology and rigid fixation with a dual plate or a nail-with-plate combination will give satisfactory outcomes in long bone non-union in lower limbs.