Fractures of the Tibial Plateau

The tibial plateau is the flat, expanded top of the shin bone or tibia which makes up the lower half of the knee joint. It is a very important part of the body for load bearing and any disruption of this area can cause abnormalities in alignment of the knee, knee stability and movement especially weight bearing and walking. Early recognition and treatment of this injury is vital to avoid the potential disability which could ensue and the longer term consequences of knee arthritis. More than half the sufferers from this fracture are over fifty years of age.

Older women make up a significant proportion of patients with this fracture, related to the degree of osteoporosis present in this group. More energetic injuries present with this fracture in younger people. When this fracture occurs, the usual method is for a downward force to be acting on the knee joint when it is suddenly pushed into a knock knee posture. Most commonly the outer condyle of the femur crushes down on the tibial condyle below it and presses the bone downwards into a fracture. Motor vehicles injuries are a common reason for this presentation, with falls from a height and sporting injuries also figuring.

Over a quarter of these injuries come from pedestrians being hit by the bumper of a car at relatively slow speeds, the bumper applying the force at a level very close to a typical knee height. Other causes can be a fall from a height or activity related such as horse riding. Fractures may vary in resulting from high or low levels of incident energy, with low energy accidents resulting in the bone been squashed down (depression fracture) and high energy events resulting in splits in the bone at various angles. Because of the complexity of presentation most surgeons accept a classification of these fractures into six groups, proposed by Schatzker and co-workers.

On assessment the surgeon will not only assess the fracture itself but the health of the surrounding tissues such as the local muscles, nerves and blood vessels. Around half of tibial plateau fractures may have accompanying injuries to the cruciate ligaments and the cartilages (menisci) which may need surgical intervention themselves. Due to the typical force being in a knock knee direction the medial collateral ligament is more likely to suffer damage than the lateral. Fractures of the medial plateau usually involve more forceful injuries due to the stronger bony areas and this can increase the risk of soft tissue complications.

Surgeons may be happy to accept a range of fracture displacement and pursue conservative or non-operative management in these cases. Lifting the depressed plateau and securing bone graft underneath it may be required if depression exceeds 5mm in depth. Open fractures, where a wound is continuous with the fracture, mean that surgery will be needed, as it is also if the blood supply has been compromised by vessel damage or if compartment syndrome has developed in the lower leg. Less severe fractures can be conservatively managed and if there is severe soft tissue compromise then surgery may have to be postponed.

On establishing the diagnoses the management plan can begin and this includes treatments aimed at limiting swelling and inflammation such as keeping the part still, resting, elevating the leg and compression of the area. Debridement, the surgical removal of any dying or dead tissue, is essential to ensure the well being of the remaining healthy tissue. Compartment syndrome, where higher and higher pressures develop in the leg compartments, is an emergency for which fasciotomy (surgical release of the tissues) is indicated.

Tibial plateau fractures have as a treatment strategy to restore alignment of the knee joint, re-establish full range of movement, and ensure stability of the knee and anatomical alignment. Overall the knee should be painless, movable and free from arthritis. Strong immobilisation of the fracture by surgery is necessary in unstable joints, with the denser bone of younger people allowing this. Functional bracing and total knee replacement may be necessary in older patients who have reduced bone density.

Jonathan Blood Smyth, editor of the Physiotherapy Site, writes articles about Physiotherapists, physiotherapy, Physiotherapists in Coventry, back pain, orthopaedic conditions, neck pain and injury management. Jonathan is a superintendant physiotherapist at an NHS hospital in the South-West of the UK.