Chronic Arthritis of Childhood – Part Two

When a smaller number of joints are affected (the oligoarticular type) there are four or fewer joints exhibiting arthritic symptoms with the larger joints being preferentially affected. Such children do not present as unwell although they may limp when asked to walk. Arthritis may be confined to one hip but if the symptoms are limited to this joint then an alternative diagnosis should be sought as this is much more common, with Perthes disease a typical outcome. Arthritis over some time develops weakness and loss of bulk in the main knee muscles and a knee bend contracture partly due to tightening of the hamstrings. A discrepancy in length of legs can develop if arthritis affects only one leg.

The polyarticular type of juvenile arthritis, which has a larger number of joints affected, is indicated by five or more joints becoming inflamed in a symmetrical manner, the same joints being inflamed on both sides. A low level fever may be present and if the joints are badly limited in terms of range of motion there is likely to be weakness of the associated muscles and a limitation in function. Examining the patient thoroughly is crucial to determine if they do have the diagnosis of juvenile arthritis, where they have particular difficulties and which form of arthritis they possess.

The definition of arthritis for the examination is the presence of swelling inside the joint (often called an effusion), along with limited joint motion and perhaps pain, warmth and redness of the joint area. It is not possible to determine swelling of some joints such as the hips but they do exhibit pains and limited ranges of movement. A definitive diagnosis may take time to establish as the arthritis may develop at the same time as the fever and the rash but can occur some months later. The lymph nodes and the liver may be enlarged and muscles may be tender to palpation. In the fewer joint form of juvenile arthritis there is often only one joint affected.

A symmetrical occurrence of arthritic changes in the major weight bearing joints and in the hand small joints is a typical finding in the polyarticular form of juvenile arthritis. The cartilage lining the joints can narrow in thickness, develop eroded areas and can form a fusion in some cases bridging the joint. Chronic changes over longer periods can include chronic joint effusions and thickened synovial membrane, subluxed joints, stiff joints and contractures, enlargement of the bone around the joint and bony deformities (often of fingers). Bone density can also reduce around the joints and the cartilage thinning can cause joint space narrowing.

Neck changes can include a limitation of cervical extension which is often not symptomatic but is an important issue because it indicates that the neck has arthritic changes within it which can progress to the joints partially dislocating in the high neck, a dangerous neck syndrome. The posterior neck structures may also fuse themselves due to the inflammation. The joints of the jaw (temperomandibular joints) can be affected by the arthritis process and this reduces the amount of growth in the jaw and limits the person’s ability to open their mouth wide. Eyes can also be affected.

The management of children with juvenile arthritis works best as a team process as many aspects need to be considered such as medication, physiotherapy, occupational therapy, family education and school function. Individual treatments on their own will not be successful. Seeing the patient for regular examinations allows the medication to be regularly reviewed and changed, aiming at a reduction in morning stiffness and the number of joints involved until the number of affected joints drops to zero. The team will likely consist of a paediatric rheumatologist, a nurse, a physiotherapist and occupational therapist and social workers to help with family and school issues.

Surgery is not routinely indicated for most of these patients although joint injections with steroids may be employed for some. Polyarticular arthritis patients may suffer severe knee and hip arthritis which can be treated with knee and hip replacement once skeletal maturity has been reached and bone growth has stopped. Encouraging patients to be active is important as resting for long periods is not helpful and more active patients do better.

Jonathan Blood Smyth is the Superintendent of Physiotherapy at an NHS hospital in the South-West of the UK. He writes articles about back pain, neck pain, and injury management. If you are looking for Physiotherapist Croydon visit his website.