The Elbow Joint

by Catherine Logan, MSPT on Jul 01, 2006

Anatomy, two common elbow joint injuries and postrehab strategies.

Elbow Joint Anatomy Review

The elbow is a “hinge” joint formed by the distal end of the humerus and the proximal ends of the radius and ulna bones. The elbow moves into flexion and extension. The trochlea and capitulum of the humerus articulate with the trochlear notch of the ulna and the radial head, respectively.

The specific articulations of the elbow joint include the humeroulnar and humeroradial articulations and the proximal radioulnar joint. The humeroulnar articulation, which is between the trochlea of the humerus and the trochlear notch of the ulna, permits flexion and extension. The humeroradial articulation is between the capitulum of the humerus and the radial head and allows pronation and supination. The capitulum fits into the slightly cupped surface of the radial head. The proximal radioulnar joint, found between the head of the radius and the ulna’s radial notch, allows rotation of the radius about the ulna (Moore 1992).

The two condyles of the humerus (found at the distal end) form the articulating surfaces at the elbow joint. Above the condyles are the lateral and medial epicondyles. The lateral epicondyle is the origin for the forearm extensor muscles, which extend the wrist. The medial epicondyle is the attachment point for the forearm flexor muscles that flex the wrist.

A fibrous capsule surrounds and encloses the elbow joint, and medial and lateral thickenings of the capsule create the joint’s intrinsic, or “collateral,” ligaments. The radial collateral ligament is on the lateral aspect of the joint, while the ulnar collateral ligament is on the medial side.

The adult elbow joint is quite stable because of the hinge-link articulation between the bones and the strength of the ulnar and radial collateral ligaments. The elbow is not as strong in children because of the late fusion of the epiphyses of the ends of the bones involved in articulation (Moore 1992).

Muscles of the Elbow Joint

The principal muscles responsible for elbow extension and flexion are the triceps brachii for extension, and the brachialis, biceps brachii and brachioradialis for flexion. Other elbow joint muscles involved in extension include the anconeus and brachioradialis. (Although the brachioradialis is primarily a flexor, it also assists in active extension.) Other flexors include the extensor carpi radialis longus, pronator teres and flexor carpi radialis. The pronator teres pronates the forearm, and the anconeus abducts the ulna during pronation. The supinator muscles supinate the forearm, but do not flex or extend the elbow joint (Moore 1992).

Lateral Epicondylitis

Individuals who suffer from lateral epicondylitis may have pain or burning in their forearm muscles. The condition is common in tennis players and is therefore given the nickname “tennis elbow.” Lateral epicondylitis may also result from occupations that involve repetitive movements such as raking, painting or using a computer mouse.

This elbow joint injury is typically caused by repetitive microtrauma that results in degeneration of the extensor carpi radialis brevis tendon. Repetitive eccentric muscle overload has been implicated (Brotzman 1996). Less commonly, the extensor carpi radialis longus tendon will be the primary pathology (Kibler, Herring & Press 1998).

Chronic overload of the tissue (from a change of activity or from an athletic/ occupational activity), or an acute traumatic fall or direct blow can cause this condition. Symptoms are generally worse during eccentric loading of the extensor muscles. Weakness in the external rotators of the shoulder, resulting in compensatory movement, is sometimes noted (Kibler, Herring & Press 1998).

Treatment for this elbow joint injury by a physical therapist or an athletic trainer will depend on what is found during a physical evaluation. Treatment may include stretching and strengthening as well as therapeutic modalities such as ultrasound, laser, iontophoresis and/or phonophoresis (methods of enhancing drug delivery through electrical current or ultrasound), electrical stimulation, etc.

Postrehab Strategies

If the elbow joint injury results from eccentric overload, eccentric strengthening with resistance tubing, as well as strength training with hand weights or dumbbells, is needed to prevent recurrence. Maintenance of elbow flexion and extension and forearm pronation/supination flexibility is also important. Proper form in athletic activities or occupational tasks is essential to avoid reinjury.

Strengthening. Strengthening the elbow joint should always be performed in a pain-free range of motion.

1. wrist extension with resistance tubing/band (3 sets, 10–12 reps)

  • Wrap one end of resistance tubing around a fist and secure the opposite end under the same-side foot.
  • With the forearm of the working arm resting on the thigh, palm down, stabilize the forearm with the opposite arm and move the wrist up into extension against the resistance of the tubing.
  • Slowly lower back to the starting position for a count of 4.

Note: Although resistance tubing is preferred for wrist extension because it supplies both concentric and eccentric resistance, a 1- to 5-pound (lb) hand weight may be substituted if tubing is unavailable.

2. wrist flexion with hand weight (3 sets, 10–12 reps)

  • Hold a light (1–5 lb) hand weight.
  • With the forearm of the working arm resting on the thigh, palm up, stabilize the forearm with the opposite arm and move the wrist upward into flexion.
  • Slowly lower back to the starting position for a count of 4.

3. forearm pronation and supination (3 sets, 5 reps)

  • Hold a weighted rod or dumbbell (about the size and weight of a hammer).
  • With the elbow stabilized at the side and bent to 90 degrees, hold the rod upright.
  • With control, slowly supinate the forearm while keeping the wrist straight and the elbow pinched into the side.
  • Return to the starting position and slowly pronate the forearm in the opposite direction.

Note: Strengthening of the shoulder external rotators may also be indicated, depending on the individual. External rotation can be done with resistance tubing; in sidelying position with a dumbbell; or with pulleys.

Flexibility. Gentle stretching is indicated initially, with low duration and high frequency. Longer stretches should be avoided until the individual can perform them without any pain.

1. wrist flexors (5–10 reps, 10-second hold)

  • Begin with the arm out straight at shoulder height, palm up.
  • With the opposite hand, gently push the hand of the working arm down.

2. wrist extensors (5–10 reps, 10-second hold)

  • Begin with the arm out straight at shoulder height, palm down.
  • With the opposite hand, gently push the hand of the working arm down.

3. forearm rotation (supination/pronation) (5–10 reps, 10-second hold)

  • Begin with the elbow at the side and bent to 90 degrees.
  • Actively supinate the forearm as far as possible without compromising the position of the elbow, and hold.
  • Repeat the same technique with pronation.

Medial Epicondylitis

Like lateral epicondylitis, medial epicondylitis can cause pain and burning in the muscles of the forearm. The condition, commonly termed “golfer’s elbow,” is not limited to golfers. It involves primarily the pronator teres and flexor carpi radialis (Kibler, Herring & Press 1998). This diagnosis is generally associated with chronic overload, and less so with trauma. It is also sometimes associated with shoulder instability, decreased shoulder internal rotation, pronator inflexibility at the elbow, or a flexion contracture of the elbow (Kibler, Herring & Press 1998).

As with lateral epicondylitis, treatment is usually conservative, and individuals are typically rehabilitated without surgery. A physical therapist or an athletic trainer may employ modalites (ultrasound, laser, iontophoresis, etc.) to reduce pain and inflammation, and work to restore flexibility and strength.

Postrehab Strategies

Strengthening. The strengthening program for clients with this condition is similar to that for clients with lateral epicondylitis, and employs tubing/bands and free weights for the wrist extensors (see above). With medial epicondylitis, if at all possible, tubing/bands should be used during the wrist flexion strengthening exercise to emphasize both the eccentric and concentric phase of the flexor group.

Note: A healthcare professional sometimes uses “counterforce” bracing to diminish the muscle tension on the injured area. It is a supplement to, not a replacement for, the strengthening exercises.

Flexibility.

1. wrist flexors (5–10 reps, 10-second hold)

  • Stand facing a table top. Place forearms on table, palms down, shoulder-width apart.
  • While keeping the elbows straight, gently lean forward until a stretch is felt in the flexor side of the forearms.

2. shoulder internal rotation (5–10 reps, 10-second hold)

  • Stand with one hand behind the back, resting on the base of the sacrum.
  • Actively move the thumb up the spine while maintaining upright posture until a gentle stretch is felt in the front of the shoulder.

3. supination/pronation stretch (5–10 reps a day, 10-second hold)

  • Begin with the elbow at the side and bent to 90 degrees.
  • Actively supinate the forearm as far as possible without compromising the position of the elbow, and hold.
  • Repeat the same technique with pronation.

Rules of Thumb

Epicondylitis, whether lateral or medial, is known to be a lingering and sometimes nagging injury. It is essential that clients progress in their exercise program without any incidence of pain or discomfort.

  • Ensure that all exercises are performed in a pain-free range of motion.
  • Initiate a gradual return to stressful activities.
  • Emphasize maintenance exercises.
  • If pain returns in the elbow, refer the client back to his or her physician or healthcare professional.

References

Brotzman, S.B. (Ed.). 1996. Handbook of Orthopaedic Rehabilitation. St. Louis: Mosby 193-258.

Kibler, W.B., Herring, S.A., & Press, J.M. 1998. Functional Rehabilitation of Sports and Musculoskeletal Injuries. Gaithersburg, MD: Aspen Publishers Inc. 216-44.

Moore, K.L. 1992. Clinically Oriented Anatomy (3rd ed.). Baltimore: Lippincott Williams & Wilkins 373-432.

IDEA Fitness Journal, Volume 3, Issue 7

© 2006 by IDEA Health & Fitness Inc. All rights reserved. Reproduction without permission is strictly prohibited.

About the Author

Catherine Logan, MSPT IDEA Author/Presenter

Catherine Logan, MSPT, is a licensed physical therapist, a personal trainer and a Pilates instructor. She is a clinical specialist for Myomo Inc., a NeuroRobotics™ company based in Boston. She a...