A common cause of knee pain in a growing child is injury to a growth plate in the front of the knee. This may be accompanied by swelling in the area. This condition is called Osgood-Schlatter's disease. It occurs most commonly in children between the ages of 10 -14. It is often associated with playing sports and aggressive bicycle riding. It is felt that the condition is primarily caused by an abnormal pull of the patellar tendon that attaches into the painful area from the kneecap. Knee pain in children may be caused by a variety of conditions. Some of these conditions may be rare but can be quite serious in nature and should be evaluated as early as possible.
1. Common Digital Deformities
Deformities of the toes are common in the pediatric population. Generally they are congenital in nature with both or one of the parents having the same or similar condition. Many of these deformities are present at birth and can become worse with time. Rarely do children outgrow these deformities although rare instances of spontaneous resolution of some deformities have been reported.
Malformation of the toes in infancy and early childhood are rarely symptomatic. The complaints of parents are more cosmetic in nature. However as the child matures these deformities progress from a flexible deformity to a rigid deformity and become progressively symptomatic. Many of these deformities are unresponsive to conservative treatment. Common digital deformities are underlaping toes, overlaping toes, flexed or contracted toes, curved toes and mallet toes. Quite often a prolonged course of digital splitting and exercises may be recommended but generally with minimal gain. As the deformity becomes more rigid surgery will most likely be required if correction of the deformity is the goal.
2. Kohler's Disease
Kohler's Disease is a spontaneous loss of blood supply to a bone in the foot called the Navicular bone. Dr. Kohler described it in 1908. The spontaneous loss of blood supply to a bone is called osteochondrosis.
3. Freiberg's Disease
The spontaneous development of pain in children generally indicates some form of injury to the growth plate of a growing bone. This can occur without a specific memorable event. When pain occurs in the ball of a child's foot the most likely cause is injury to the growth plate of one of the long bones behind the toes called metatarsals. The most common bone involved is the metatarsal behind the second toe. When numbering the toes the big toe is the first toe.
This condition is called Freiberg's disease. This disorder is most frequently seen in the adolescent between the ages of 13 - 15 years of age. It is three times as likely to occur in females as compared to males. The pain is a result of a loss of blood flow to the growth plate in the bone.
4. Metatarsus Adductus
Metatarsus adductus is a congenital deformity of the foot where there is increased curvature of the forefoot. This gives the foot the appearance of a “C” shape. This deviation of the metatarsals or visual effect of in-toeing is a deformity that occurs at the midfoot of the foot. The diagnosis of metatarsus adduction is relatively straightforward and is predominantly a clinical diagnosis. The exact cause of metatarsus adductus is not fully understood but is considered to be caused by intrauterine position and pressures. There may also be a genetic component to the deformity.
A flatfoot deformity is where the arch on the inside border of the foot is more flat than normal. Flatfoot deformities can occur in all age groups, but appear most commonly in children. Some of these children grow up into adults who have feet with normal arches, but many of these children have pain related to their flatfoot deformity throughout their lives. It is very important that children with flatfoot deformity be evaluated by a podiatrist to determine if they need treatment to prevent future pain or deformity in their feet.
6. Tarsal Coalition
A tarsal coalition is a bone condition that causes decreased motion or absence of motion in one or more of the joints in the foot. The lack of motion or absence of motion is due to abnormal bone, cartilage or fibrous tissue growth across a joint. When excess bone has grown across a joint there is usually little or no motion in that joint. Cartilage or fibrous tissue growth can restrict motion of the affected joint to varying degrees causing pain in the affected joint or in surrounding joints.
7. Club Foot
Clubfoot describes a range of foot abnormalities usually present at birth (congenital) in which the baby's foot is twisted out of shape or position. The term "clubfoot" refers to the way the foot is positioned at a sharp angle to the ankle, like the head of a golf club. Clubfoot is a common birth defect and is usually an isolated problem for an otherwise healthy newborn.
8. Bowleg and Knock-Knee
Bowleg (or genu varum) is a condition where the legs are bowed outwards in the standing position. The bowing usually occurs at or around the knee, so that on standing with the feet together, the knees are far apart.
Knock-knee (or genu valgum) is a condition where the legs are bowed inwards in the standing position. The bowing usually occurs at or around the knee, so that on standing with the knees together, the feet are far apart.
Most people have some degree of bowleg or knock-knee and is considered within the limits of normal structure and function. During development in the first few years of life, because of rapid and differential growth around the knees, most children are bowlegged from birth till age 3, then become knock-kneed till age 5, then straighten up by age 6 or 7. In most children, even as they grow through these phases, the bowleg and knock-knee are not severe, and do not engender concern on the part of the parents. In some instances, the bowleg or knock-knee gets quite obvious, and becomes worrisome for the parents.
Corrective surgery can be done using physeal manipulation with 8-plate or osteotomy and K-wiring / plating or Ilizarov frame application
9. Blount’s Disease
Blount disease is an uncommon growth disorder characterized by disordered ossification of the medial aspect of the proximal tibial physis, epiphysis, and metaphysis. This progressive deformity is manifested by varus angulation and internal rotation of the tibia in the proximal metaphyseal region immediately below the knee. The natural history of this disease leads to irreversible pathologic changes, especially at the medial portion of the proximal tibial epiphysis because of growth disturbances of the subjacent physis.
Corrective surgery can be done using physeal manipulation with 8-plate or osteotomy and K-wiring / plating or Ilizarov frame application.