Correction of Complex Deformities

Complex deformities of the limbs cause significant derangement in shape of limbs. These conditions significantly affect the individual's ability to perform daily activities and may cause a permanent disability.

Some of the common complex deformities of lower limbs include:

• Congenital genu recurvatum, genu varus: Genu recurvatum is also called as bow knees, back knee, or knee hyperextension. It is a deformity in the knees where the knees bend backward.
  
• Genu valgum: genu valgum also known as knocked knees is a condition where the knees bend inward touching each other while the ankles stay apart giving the appearance of legs turned inward.
  
• Limb length discrepancy: Limb length discrepancy is a condition of unequalled leg lengths where one leg will be shorter than the other.

These complex deformities require surgical correction and may be done by different methods. Depending on the complexity the conditions can be treated by two methods, open reduction and closed reduction. In open reduction, the surgeon makes an incision on the skin directly and inserts internal fixators. In closed reduction, external fixators are used without making any incision. Some of the surgical methods are described as follows:

External fixation: In this method, the surgeon places external fixators such as pins or screws into the fractured bone on either side of pelvis. These pins are then connected to clamps or rods outside the skin which will form an external frame that will bring about stability and allow the bone to heal.

Internal fixation: In this method, your surgeon makes an incision on the injured areas and inserts internal fixators such as wires, screws, pins, or plates. These internal fixators are fixed either in front of the pelvis or at the back. This helps to prevent further injury like arthritis and also prevents displacement of bone. Your doctor may suggest using crutches or apply casts and avoid weight-bearing activities or physical work for few weeks to allow bones to join.

Ilizarov Method: The Ilizarov method is a minimally invasive procedure where correction of deformities can be done using the circular ring fixator. The Ilizarov procedure is done in 3 phases:

• Operative phase: In this phase, "K" wires are passed through bones proximal and distal to the deformity and then fixed to the Ilizarov rings using wire fixation bolts. Then the rings are connected by hinges and threaded rods.
• Distraction phase: This phase is started after 10 days of operative phase where twits or pressure is applied that stimulates the new bone growth. Bone growth of 3 mm/day may be possible and the distraction phase is continued till the deformity is corrected. Once the deformity is fully corrected, the apparatus is locked.
• Consolidation phase: It is the period between the locking of apparatus and the completion of solid bone formation which may takes about 2-3 months. Once the bone is solid, the Ilizarov ring fixations will be removed. The patient is mobilized initially for partial weight bearing and later to full weight bearing with support. After removal, a cast made of plaster of Paris (POP) is placed for a month for protection.