This is reconstructing the damaged or deformed knee, and prevent it from reaching the stage of future replacement. Reconstruction may be required to correct bony abnormailities, such as crooked legs, or wrongly healed knee fractures. Reconstruction may also be needed for correcting ligament problems. The commonest reconstructing surgery is deformity correction. It may be in the form of reconstruction of a part of the knee where it became necessary to remove the damaged part, in a case of bone tumour, for example. Before knee reconstruction, thorough understanding of the deranged biomechanics of the knee are required. For this, we do special long leg films, to see how weight bearing happens across the knee. Some examples of such surgery are given below:
HKA, is a special x-ray, where bony structure of the whole body, below the waist is seen on one x-ray film. This helps in knowing the alignment of the whole limb with the patient standing. This is done using a special computer software, which calculates the deformity of the leg in degrees. HKA helps the surgeon to know the severity of deformity, and what special steps are required to correct the same during surgery. Deformity of the leg more than 3 degrees is a danger sign, as this leads to faster degeneration of the knee (something like wearing off of the tyre of a car wheel which is mal-aligned). The same x-ray done post-operation, also tells about accuracy of the surgery. It is ideal to have alignment corrected as close to 0 degree as possible.