HEALTH

Distal Femoral Fractures

Introduction 

Surgical stabilization is required by most of the distal femoral fractures which result in the conservative treatment of such injuries, while in case of the displaced fractures the results can be unsatisfactory. The treatment has been improved with the introduction of several implants that include 95° condylar plate, retrograde intramedullary nail femur, and dynamic condylar screw (DCS) although the problems persist. There are certain complications that can be encountered like Non-union, knee stiffness, infections, delayed union, etc.

These fractures are majorly found in young adults due to the high energy trauma and in the case of elder people with osteoporosis, this can attribute the difficulty in treating the distal femoral fracture. The fracture in adults is accompanied by the fragmentation of metaphyseal component and intra-articular fracture component and severe injuries of soft tissues which later creates the problem of Ortho Implants loosening and loss of fixation. 

After introducing the bridge plating principles, indirect fracture reduction, locking compression plates (LCP), and minimally invasive technique there are certain difficulties that have been resolved after the associated treatments but certain problems remain as usual with these methods and demands technique. 

Classification 

The Muller AO classification is going to be used for the fracture classification of the distal femur. There are different types of fractures where type A fractures are extra-articular fractures, type B partial articular fracture, and type C complete articular fractures. 

Indications and contraindications for MIPO

For the treatment of distal femur fracture, there are various advantages of indirect fracture reduction along with submuscular plating, the treatment lies intact with the envelope of soft tissues which surrounds the fracture, preserves biology and enhance the chances of Fracture union which reduces the requirement for bone grafting along with the infection incidences. This majorly applies to the diaphyseal and metaphyseal fracture components which basically require the axial alignment, restoration of length, and rotation while on the other hand open and anatomical reduction is required by the components of the fracture. When there is adequate relative stability then the compression along with lag screw fixation is required in the metaphyseal/ diaphyseal region for the articular fractures. 

With the partial articular involvement in the type B fractures, any advantage is not conferred by the MIPO unless there is an association of the femoral shaft fracture. Open reduction is the first choice of treatment in case of the isolated type B fractures of the articular fragment which is then followed by the interfragmentary compression with help of lag screws and supplementation if required with the addition of the buttress plate. 

If the fracture has been greater than 2 weeks, then it becomes more difficult to perform MIPO. It is all due to the scarring and soft tissue con fractures which become more problematic in case of the indirect fracture reduction. 

If there is a presence of the severe contamination of the wound or infection, then MIPO is strictly prohibited. If there is any associated vascular injury, then also it is contraindicated. 

Surgical Anatomy 

There is a unique anatomical shape of the distal femur which can be viewed from an end-on view, from the vertical surface there is 10 inclination on the lateral surface while a slope of 20 to 25 degrees at the medial surface. There is a slope of around 10 degrees from the line which is drawn from the anterior aspect of the lateral femoral condyle to the anterior aspect of the medial femoral condyle. 

While inserting locking screws or blade plates the complete anatomical details are required. To avoid any kind of joint penetration, it is required to place them parallel to the femorotibial and patellofemoral joints. 

Also while positioning plate on the distal femur’s lateral aspect, if there is no fit along the lateral femoral condyle which lies flat before the insertion of screws then a high risk of rotational malalignment can be encountered for the distal articular block after completion of the screw fixation. The placement of bone plate too far from the posterior of the lateral femoral condylar surface can result in the risk of blade or screw penetration to the intercondylar notch, apart from this it can also lead to the medial displacement of articular blocks including the internal emotional deformity when later the articular block is fixed in the shaft fragment. 

For typical displacement in the distal articular block is the result of muscle attachment to the distal femur which is followed by a fracture named shortening with varus and extension deformity. Shortening is the result of quadriceps pull and hamstring muscles while extension and varus deformity can result in the unopposed pull of gastrocnemius and adductors, respectively. 

The tibial, common peroneal nerves, and the popliteal vessels lie in the proximity to the distal femur’s posterior aspect. Due to this around 3% of the vascular injuries occur and 1% of the distal femur fractures with the nerve injuries. 

Preoperative assessment and timing for surgery

The preoperative radiological and clinical assessment should be carried out. Clinical assessment in the case of high energy injuries in young patients should include associated injuries, hemodynamic status, soft tissue status, and neurovascular status of the limb injury. 

In the case of the low energy fractures in the elder patients the cardiovascular status and hemodynamics, quality of bone, and other comorbidities should be properly assessed. 

The lateral and AP X-rays of the knee and femur should be included in the radiological assessment. In some cases, the traction films can also be required for providing a lot of information on the morphology of the fracture. 

seemagupta

Seema Gupta is a well-known financial and tech advisor with the abilities to keep a track and predict the market trends with the utmost accuracy. Her extensive knowledge in finance and tech is remarkable as she has worked on different financial and sectors dealing with the entire range of loans. She is also an expert in writing many finances and tech related articles and blogs, so she is a renowned finance blogger too.