Joint Trauma and Osteoarthritis

 Definition 

Osteoarthritis (OA) is the most common form of arthritis, affecting over 20 million Americans.  Also known as “wear-and-tear” arthritis, or degenerative arthritis, OA is a chronic disease affecting synovial joints.  Synovial joints are composed of cartilage, bone, and joint fluid all contained within a joint capsule.  The smooth cartilage covering the ends of the bones within the joint allows for the significant range of motion seen in the hip or knee joint.  OA occurs when this cartilage begins to break down.

 As the cartilage within the joint erodes, a series of changes lead to deformity of the joint.  Cartilage destruction eventually exceeds the body’s ability to make new cartilage.  As cartilage disappears, the bones of the joint begin to rub against each other. This causes pain and swelling.  It has also been found that the amount of fluid in the joint, particularly a fluid component called hyaluronic acid, is decreased in the osteoarthritic joint.

Signs and Symptoms 

The pain of OA is usually insidious and manifests over several years.  The pain is exacerbated with activity and is usually relieved by rest.  As the disease progresses, range of motion becomes limited and pain can occur at rest.

Etiology 

There are two categories of OA – primary and secondary.  Primary, or idiopathic, OA appears without any apparent cause.  It is usually seen in the elderly.  Secondary OA occurs in joints that have sustained an injury.  This injury can be a result of previous trauma to the joint, infection of or crystal deposition within the joint, or as a result of long-standing rheumatoid arthritis.  Secondary OA is usually seen in a younger population.

 Post-traumatic OA is a relatively common and problematic disease.  Previous studies found that young athletes who sustain a joint injury of the knee or hip have a substantially increased risk of developing OA in the traumatized joint later in life.  The study concluded that young adults with joint injuries should be targeted for primary prevention of OA.

Prevention 

The best methods for prevention have not been well studied or firmly established.  Only recently, a National Institutes of Health study was begun to better understand the prevention of post-traumatic OA.  The following therapies, though effective in slowing the progression of OA, have not necessarily been shown to prevent the development of OA.

 1.  Weight loss 

Particularly in overweight people, weight loss can lessen the shock to the joints.  In the long run, this translates to decreased “wear-and-tear.” 

2.  Aerobic exercise 

Exercise has been shown to decrease pain and increase joint flexibility in patients with OA.  Following joint trauma, exercise is promoted as part of rehabilitation therapy to maintain joint range of motion and strength.  The type and duration of exercise will depend on the degree of joint trauma and should be recommended by a physician or rehabilitation therapist.

 3.  Prolotherapy 

Prolotherapy involves the injection of an irritant solution (usually dextrose) into a damaged joint.  The subsequent localized inflammatory reaction is believed to increase the blood supply around the joint and promote the damaged tissue to repair itself. Some studies have shown prolotherapy to be effective at controlling pain and reversing joint damage.

4.  Glucosamine / Chondroiton sulfate 

Glucosamine is a component of hyaluronic acid.  Multiple clinical studies have compared glucosamine with placebo and with standard anti-inflammatories (such as ibuprofen).  In some studies, glucosamine has shown significant long-term benefit over placebo and anti-inflammatories with respect to reducing long-term pain, reversing cartilage damage, slowing down joint-narrowing, and helping to restore joint function.  Therapy involves 500mg glucosamine tablet taken orally three times a day.  Often, glucosamine is taken in combination with chondroitin sulfate.  Chondroitin sulfate has also been found to improve symptoms.  When taken together, these supplements have been shown to not just reduce symptoms, but possibly slow or halt the disease progression itself.  Research into these exciting supplements is ongoing.

5.  Vitamin B5 

Low vitamin B5 levels have been implicated in the development and degree of severity of both osteoarthritis and rheumatoid arthritis. Whether supplementation with vitamin B5 can help prevent the development of OA has not been confirmed.

Authors: Bishoy Zakhary, B.A., Creighton University School of Medicine, Omaha, NE

   Alex Visco, M.D., New York-Presbyterian Hospital, The University Hospital of Columbia and Cornell, New York City, NY