Deformity correction refers to the process of adjusting or modifying musculoskeletal deformities—most commonly a leg deformity, foot deformity or ankle deformity, though it can be used for deformities of almost any part of the body—through surgery or the use of orthotic devices. The deformities addressed by deformity correction usually stem from: congenital and developmental deformities, which are often present at birth and get progressively worse as the patient ages; physical traumas, such as sports injuries, car accidents or falls; and diseases such as diabetes, obesity, cerebral palsy and osteomyelitis. The specific treatment will depend on the deformity being treated, but generally speaking, they either involve surgery or the use of external fixation devices. A brief description of the treatments used for certain deformities is given below.
If treated early enough—before the age of four—patients may only need to wear leg braces for several weeks. For patients over the age of four, surgery is often required. The main procedures used for bow legs include: knee realignment, in which the knee bones are surgically realigned and fixed in place with pins, plates, screws or staples until they heal; and osteotomy, in which an incision is made and a small wedge is removed from the tibia (and sometimes the fibular as well), and then the leg bones are realigned and fixed using pins and an external cast or an external fixation device.
While knock knees usually self-correct in early childhood, this isn’t always the case, and sometimes surgery is required. The surgical options for knock-knee are the same as for bow legs: knee realignment and osteotomy.
Deformity correction for fractures that have not properly healed usually involve the use of an external fixation device that holds the bones in place to facilitate healing. The most common external fixation devices or nonunions are the Taylor spatial frame and the Ilizarov apparatus.
Surgeons performing a limb-length surgery will microscopically fracture the patient’s leg bone, and then apply an Ilizarov apparatus or Taylor spatial frame to keep the bone separated by a few micrometers. As the new bone grows, the external fixation device is used to readjust and widen the gap between the bones. If all goes well, the new bone will continue to grow between the gap until the correct bone length is reached. After that, the fracture is allowed to close and heal.
Deformity correction is used to allow individuals with dwarfism to achieve addition skeletal growth. Most frequently, an Ilizarov apparatus or Taylor spatial frame is used, along with the same surgical technique used to address limb length discrepancy. Dwarfism often leads to other conditions that require deformity correction, including bow legs and knock-knee.
Surgeons seeking to correct hammertoe, a toe that’s curled upward because of a bend in its middle joint, will most commonly use either arthroplasty or joint fusion. In arthroplasty, the surgeon will remove a small amount of bone from the affected joint and then realign it. In a joint fusion, the two bones forming the joint will be linked and combined using a pin, screw or bone graft. The bones then grow together, which straightens the toe but leaves the joint rigid and immobile.