Intersection Syndrome

ExitCare ImageIrritation of tendons in the wrist and forearm may cause pain and inflammation on the thumb side (radial) of the forearm. This pain is a sign of intersection syndrome. It is called intersection syndrome because the irritation occurs where four separate tendons intersect. Two of these tendons are used for extending the wrist: extensor carpi radialis longus (ECRL), and extensor carpi radialis brevis (ECRB). The other two are used for extending the thumb: extensor pollicus brevis (EPB), and abductor pollicus longus (APL). Each of the four tendons has a covering, called a sheath. The tendon sheaths secret a fluid, which lubricates the tendons. This allows them to move smoothly. However, these sheaths have a tendency to become inflamed. That causes the tendons to stop gliding smoothly. This is why intersection syndrome may make it painful to extend the wrist or thumb.

SYMPTOMS

  • Pain, tenderness, swelling, warmth, or redness, about 2 inches up the arm from the wrist.

  • Pain that gets worse when extending the wrist or thumb.

  • Limited motion of the thumb or wrist.

  • Crackling sound (crepitation), when the tendon or wrist is moved or touched.

CAUSES

  • Intersection syndrome is most often an overuse injury, caused by repeated motions of the hand and wrist.

  • Sudden increase in activity or change in activity.

RISK INCREASES WITH:

  • Sports that involve repeated hand and wrist motions (rowing, weightlifting, racquet sports).

  • Heavy labor.

  • Poor hand and forearm strength and flexibility.

  • Failure to warm up properly before activity.

PREVENTION

  • Warm up and stretch properly before activity.

  • Allow time for rest and recovery of the wrist, when it becomes painful.

  • Maintain wrist and forearm fitness:

  • Forearm, wrist, and hand flexibility.

  • Muscle strength and endurance.

  • Use proper exercise technique.

PROGNOSIS

Intersection syndrome is usually curable, if treated properly. Rest and recovery may take up to 6 weeks.

RELATED COMPLICATIONS

  • Longer healing time, if not properly treated, or if not given enough time to heal.

  • Chronic inflammation of the tendon sheaths. This causes persistent symptoms, and possible rupture of one or more tendons.

  • Recurring symptoms, especially if activity is resumed too soon.

  • Risks of surgery: infection, bleeding, injury to nerves, continued pain, incomplete release of the tendon sheath, recurring symptoms, cutting the tendons, tendons sliding out of position, and weakness of the wrist or thumb.

TREATMENT

Treatment first involves ice and medicine, to reduce pain and inflammation. You may be advised to begin strengthening and stretching exercises. These can be done at home, or with a therapist. If possible, it is helpful to modify any aggravating activity, if the modification results in less severe symptoms. Your caregiver may recommend restraint with a cast, splint, or brace, to reduce friction within the tendon sheaths. Your caregiver may recommend a corticosteroid injection to reduce inflammation. Surgery may be needed, to release the tendons.

MEDICATION

  • If pain medicine is needed, nonsteroidal anti-inflammatory medicines (aspirin and ibuprofen), or other minor pain relievers (acetaminophen), are often advised.

  • Do not take pain medicine for 7 days before surgery.

  • Prescription pain relievers are usually prescribed only after surgery. Use only as directed and only as much as you need.

  • Corticosteroid injections are used in extreme cases, to reduce inflammation. These injections should be given only if necessary, because they may only be given a limited number of times.

COLD THERAPY

  • Cold treatment (icing) should be applied for 10 to 15 minutes every 2 to 3 hours for inflammation and pain, and immediately after activity that aggravates your symptoms. Use ice packs or an ice massage.

SEEK MEDICAL CARE IF:

  • Symptoms get worse or do not improve in 2 to 4 weeks, despite treatment.

  • You experience pain, numbness, or coldness in the hand.

  • Blue, gray, or dark color appears in the fingernails.

  • Any of the following occur after surgery: increased pain, swelling, redness, drainage of fluids, bleeding in the affected area, or signs of infection.

  • New, unexplained symptoms develop. (Drugs used in treatment may produce side effects.)