With knee problems in children, it is imperative that back-and hip problems are excluded as the cause of referred pain to the knee. Various hip problems commonly cause knee problems and pain in children.
Septic arthritis/osteitis is a potentially devastating condition involving infection of the knee joint or the surrounding spongy bone. A healthy child, usually under 10 years old, will complain of knee pain, swelling and an inability to walk. Often these children may report a fall or some other mechanism of injury which is, in fact, unrelated to the problem at hand. This does, however, create the potential for a missed diagnosis with potentially fatal results. If these infections are not rapidly drained surgically, the infection spreads to the bloodstream and may infect other organs such as the lungs and heart. The major local complication of septic arthritis is rapid cartilage erosion with early-onset arthritis of the knee joint.
In a group of conditions known as “traction apophysitis”, children (usually boys in their early teens) develop pain around the various bone-tendon insertions around the extensor mechanism complex of the knee. The most common condition is “Osgood-Schlatter” disease, which involves the insertion of the kneecap tendon into the tibia. Treatment of these conditions is non-surgical with physiotherapy and activity modification.
Limb alignment issues in children are often of concern to parents. Most of these cases involve normal bilateral variants. It must be borne in mind that leg alignment changes during the first eight years from bow legs to knock-knees to mechanically straight legs. If an alignment difference exists between the two legs or if the alignment is extremely abnormal, the child may be suffering from growth problems at the cartilage growth plate. This may be caused by an injury or conditions such as Blount’s disease. If pathological limb alignment issues are not addressed early, the excessive wear on the overloaded knee compartment will lead to rapid onset knee arthritis. Correction of malalignment in children is much easier than in adults because growth at the growth plates can be differentially inhibited, resulting in gradual correction.
