Limb deformities are conditions that affect the bones, muscles and tendons of the lower limb. Most of the conditions are generally asymptomatic, except for a cosmetic concern. Some are harmless and self–correcting in nature or may sometimes require simple treatment. Some deformities, however, are complex and are corrected by surgery. Limb deformities can be congenital- present at birth or may occur at a later stage as a result of fracture, infection, arthritis or tumour. Congenital deformities of the lower limbs are the developmental disorders that cause alteration in the shape and appearance of the legs. There are several factors such as genetic factors which influence the foetal growth in the womb and teratogenic drugs and chemicals that can cause congenital deformities.
Some of the deformities of the lower limb and their correction are discussed below:
Calcaneovalgus foot: This postural deformity is located at the ankle joint and the foot appears to be bent upwards. The foot appears flat and the heel bone turns outwards. The treatment depends upon the severity of the condition. In mild cases, gentle stretching exercises and massage to the foot performed by the parent can help. Splinting can be done in moderate cases and if there is no improvement with stretching exercises after 1-2 months. In cases of severe deformity, serial casting is needed for up to 3 months. Then splints are given to be worn only in the night for 2-10 weeks as a part of maintenance therapy.
Congenital Vertical Talus (CVT): CVT is also known as Rocker-Bottom foot, is a rare condition and is often mistaken for calcaneovalgus, but it is a rigid deformity and not as flexible as calcaneovalgus foot. The initial treatment starts with serial manipulations and application of casts. Cast treatment can only improve the deformity. Definitive correction can be achieved by a soft-tissue release operation. The type of surgical procedure performed depends on the age of the patient, severity of the deformity and surgeon’s preference. In children up to the age of three, open reduction of the talonavicular joint is traditionally done. Children between the ages 4 and 8 are usually treated with open reduction combined with extraarticular arthrodesis (surgical fusion of joint). Patients above 8 years may require a triple arthrodesis.
Congenital clubfoot (Talipes equinovarus): Congenital clubfoot is the most common and obvious of all the foot deformities. The feet may become twisted inwards in such a way that top of the foot comes in place where the bottom should be. The initial treatment for clubfoot is the use of non-surgical methods such as serial manipulation and casting using the Ponseti method, taping, physical therapy and splinting, and continuous passive motion with a machine. Surgical correction is required in severe cases that do not respond to stretching and may include release of soft tissue and joint contractures, tendon lengthening, and fixation of temporary pins in the foot.
Flat foot (Pes planus): Flat feet, also known as pes planus is a deformity of the feet, in which the arch running lengthwise along the sole of the feet has collapsed or has not formed at all. Non surgical treatment options include activity modification, orthotic devices, physical therapy, medications and shoe modification. Surgical procedures may be performed and can include tendon transfers, tendon lengthening, bone realignment, joint fusion, or implant insertion.
Metatarsus adductus: In this condition the forefoot is bent or turned inwards towards the midfoot. The lateral side (outer border) of the foot is curved making the foot appear like a kidney bean. If your child’s foot is flexible enough to be straightened, no further treatment is required other than periodic follow-ups. In cases where the problem does not improve, stretching exercises of the foot will be taught and your child may have to wear a splint or special kind of shoes called “reverse-last shoes”. Casts if needed will be placed before the child is 8 months old, as better results can be achieved during this period. Surgery may be required in rare cases.
Tarsal coalition: Tarsal coalition is a developmental deformity that occurs because of fusion between two bones (tarsal bones) at back of the foot. The non-surgical methods include use of orthotic devices, physical therapy, injection of anaesthetic agent and nonsteroidal anti-inflammatory medications (NSAID’s). Surgery involves resection of the bony fusion to establish normal range of motion.
Leg length discrepancy: Leg length discrepancy is a condition in which one leg is shorter than the other leading to problems in posture and walking pattern. There may be associated pain in the back, hip knee or ankle. It can be corrected by a reconstructive procedure called limb lengthening during which the deformed bone is lengthened by replacing the lost bone.
Congenital genu varus (bowed legs): It is a normal variation in the appearance of the legs seen in children below 2 years and gradually improves by the age of 3 to 4 years. Night splints may be given or osteotomy can be performed in severe cases.
Congenital Hip Problems: Congenital hip problems that can affect children are of two types, femoral anteversion and developmental dysplasia of the hip (DDH). Femoral anteversion is the condition in which the femur (thigh bone) becomes twisted inwards causing the child’s knees and feet to turn inwards (“pigeon-toed” appearance). Usually, no treatment is required as the defect is self-correcting. Surgical treatment may be considered if the condition is severe and the child is above the age of 8. The surgery called, femoral derotation osteotomy is done which involves cutting the femur bone and rotating it to bring it to correct position. Developmental dysplasia of the hip (DDH) is a condition in which the femur (thigh bone) partially or completely slips out of the hip socket causing dislocation at the hip joint. Pavlik harness is used in newborns and infants below 6 months of age in order to hold the hip joint in place during growth of the child. Surgical treatment for this condition includes closed reduction with hip spica casting and open reduction.