Fractures distant from the implant are commonly comminuted in the setting of osteoporotic bone. These fractures can be treated similarly to a femur without prosthesis, with attention towards proximal fixation.
It is important to review prior radiographs of the total hip replacement to evaluate whether or not the stem is stable.
Reduction of comminuted supracondylar femur fractures can be exceptionally difficult to obtain and maintain.
This is complicated by the need to span the entirety of the femur because of the total hip replacement.
Careful attention must be given to both coronal and sagittal plane alignment.
4. Implant considerations
Given the complexity of healing of Vancouver C comminuted supracondylar fractures, it is possible to utilize both an intramedullary nail in a retrograde fashion, along with lateral plating support of the fracture. This can allow for earlier mobilization.
To achieve fixation around the intramedullary nail at the knee, a variable angle locking plate might be beneficial.
Note: If the patient has a total knee replacement, it must be confirmed that it is an open box total knee femoral component. That will allow for the passage of an intramedullary device. Resources are available that document the size of the opening in most commercially available total knee replacement designs.
It is recommended that a replacement polyethylene component for the knee is available if damage should occur to the existing polyethylene.
5. Intramedullary nail application
Opening the medullary canal
A guide wire is introduced into the distal femur segment in standard retrograde nail fashion.
The distal femur is opened utilizing a cannulated drill bit of appropriate size.
The guide wire and the drill bit are removed, and a ball tipped reaming wire is introduced across the proximal segment, the fracture site and up to the distal tip of the femoral prosthesis.
The femur is prepared performing sequential reaming.
The intramedullary nail is inserted over the guide wire into the distal fragment, to abut the femoral prosthesis.
The nail is then interlocked proximally and distally utilizing standard techniques.
Note: Attachment plates require small fragment locking screw fixation.
7. Aftercare following ORIF
Postoperative management should include careful monitoring of hematocrit and electrolytes particularly in the elderly patients.
Postoperative IV antibiotics should be administered up to 24 hours.
Consideration should be given to anticoagulation for a minimal course of 35 days. If there are thromboembolic complication this treatment is extended.
Drains can be discontinued when output is less than 30 to 50 cc per 12 hours.
Immediate mobilization of the patient should commence. If fracture stability will allow, the patient should be made weight bearing as tolerated as soon as possible. Long periods of limited weight bearing are extremely detrimental to patient recovery.
Combined constructs of intramedullary nail and plate theoretically provide a load sharing environment, which is conducive to early weight bearing.
Avoidance of edema postoperatively is critical for both wound healing and patient mobilization. This can be aided by pneumatic compression devices. If negative pressure wound therapy is utilized, it can be discontinued after 5 to 7 days. Staples or sutures are typically removed at 14 to 21 days.