How is the elbow designed and what is its function?

The elbow is the joint where three long bones meet in the middle portion of the arm. The bone of the upper arm (humerus) meets the inner bone of the forearm (ulna) and the outer bone of the forearm (radius) to form a hinge joint. The radius and ulna also meet in the elbow to allow for rotation of the forearm. The elbow functions to move the arm like a hinge (forward and backward) and in rotation (twisting outward and inward). The biceps muscle is the major muscle that flexes the elbow hinge. The triceps muscle is the major muscle that extends the elbow hinge. The outer bone of the elbow is referred to as the lateral epicondyle and is a part of the humerus bone. Tendons are attach to this area which can be injured, causing inflammation or tendinitis (lateral epicondylitis, or tennis elbow"). The inner portion of the elbow is a bony prominence called the medial epicondyle. Additional tendons from the muscles attach here and can be injured, causing medial epicondylitis, "golfer's elbow." A fluid-filled sac (bursa), which serves to reduce friction, overlies the tip of the elbow (olecranon bursa). The elbow can be affected by inflammation of the tendons or the bursae (plural for bursa), or conditions that affect the bones and joints, such as fractures, arthritis, or nerve irritation.

What injuries can cause elbow pain?

Tendinitis

• Lateral Epicondylitis (Tennis Elbow)
  
  The lateral epicondyle is the outside bony portion of the elbow where large tendons attach to the elbow from the muscles of the forearm. These tendons can be injured, especially with repetitive motions of the forearm, such as using a manual screwdriver, washing windows, or hitting a backhand in tennis play. Tennis elbow results with inflammation of the tendons causing pain over the outside of the elbow, occasionally with warmth and swelling, but always with local tenderness. The elbow maintains its full range of motion, as the inner joint is not affected, and the pain can be particularly noticed toward the end of the day. Repeated twisting motions or activities that strain the tendon typically elicit increased pain. X-rays are usually normal, but can reveal calcium deposits in the tendon or reveal other unforeseen abnormalities of the elbow joint.
  
  The treatment of lateral epicondylitis includes ice packs, resting the involved elbow, and antiinflammatory medications. Antiinflammatory medications typically used include aspirin and other nonsteroidal antiinflammatory drugs (NSAIDs) such as naproxen (Naprosyn), diclofenac ( Voltaren), and ibuprofen (Motrin). Bracing the elbow can help. Simple braces for tennis elbow can be found in community pharmacies and athletic goods stores. Local cortisone injections are given for persistent pain. Activity involving the elbow is resumed gradually. Ice application after activity can reduce or prevent recurrent inflammation. Occasionally, supportive straps can prevent reinjury. In severe cases, an orthopedic surgical repair is performed.
  
  
• Medial Epicondylitis (Golfer's Elbow)
  
  Medial epicondylitis is inflammation at the point where the tendons of the forearm attach to the bony prominence of the inner elbow. As an example, this tendon can become strained in a golf swing, but many other repetitive motions can injure the tendon. Golfer's elbow is characterized by local pain and tenderness over the inner elbow. The range of motion of the elbow is preserved because the inner joint of the elbow is not affected. Those activities which require twisting or straining the forearm tendon can elicit pain and worsen the condition. X-rays for epicondylitis are usually normal but can indicate calcifications of the tendons if the tendinitis has persisted for extended periods of time.
  
  The usual treatment involves ice packs, resting the elbow, and medications including aspirin and other NSAIDs. Examples of NSAIDs include naproxen (Naprosyn), diclofenac (Voltaren), and ibuprofen (Motrin). With severe inflammation, local corticosteroid (cortisone ) injections are sometimes given. Using a strap can prevent reinjury. After a gradual rehabilitation exercise program, return to usual activity is best accompanied by ice applications after use. This helps to avoid recurrent inflammation.

Olecranon Bursitis

Olecranon bursitis (inflammation of the bursa a the tip of the elbow) can occur from injury or minor trauma, as a result of systemic diseases such as gout or rheumatoid arthritis, or can be due to a local infection. Olecranon bursitis is typically associated with swelling over the tip of the elbow, while range of motion of the inner elbow joint is maintained.

Fractures

The bones of the elbow can break (fracture) into the elbow joint or adjacent to the elbow joint. Fractures generally require immobilization and casts and can require orthopedic pinning or open joint surgery.

Sprain

A sprain is a stretch or tear injury to a ligament. One or more ligaments can be injured during a sprain. This might occur when the elbow is hyperextended or simply jammed, such as in a "stiffarm" collision. The severity of the injury will depend on the extent of injury to a single ligament (whether the tear is partial or complete) and the number of ligaments involved. Treatment involves rest, ice, immobilization, compression, and antiinflammation medications.

What are diseases and conditions that can cause elbow pain, and how are they treated?

Arthritis of the Elbow

Inflammation of the elbow joint (arthritis) can occur as a result of many systemic forms of arthritis, including rheumatoid arthritis, gouty arthritis, psoriatic arthritis, ankylosing spondylitis, and reactive arthritis (formerly called Reiter's disease). Generally, they are associated with signs of inflammation of the elbow joint, including heat, warmth, swelling, pain, tenderness, and decreased range of motion. Range of motion of the elbow is decreased with arthritis of the elbow because the swollen joint impedes the range of motion. For more information on these conditions, please read the following articles: Rheumatoid Arthritis, Gout, Psoriatic Arthritis, Ankylosing Spondylitis, Reactive Arthritis.

Cellulitis

Inflammation of the skin related to infection ( cellulitis) commonly occurs as a result of abrasions of the skin. When abrasions or puncture wounds occur, bacteria on the surface of the skin can invade the deeper layers of the skin. This causes inflamed skin characterized by heat, redness, warmth, and swelling. The most common bacteria that cause cellulitis include Staphylococcus and Streptococcus. Patients can have an associated low-grade fever. Cellulitis generally requires antibiotic treatment, either orally or intravenously. Heat application can help in the healing process. Cellulitis can lead to infection of the olecranon bursa, causing olecranon bursitis, as described above.

Infected Elbow Joint (Septic Arthritis)

Infection of the elbow joint with bacteria ( septic arthritis) is uncommon. It is most often seen in patients with suppressed immune systems or diabetes, those taking cortisone medications, or intravenous drug abusers. The most common bacteria that cause infection of the elbow joint are Staphylococcus and Streptococcus. Septic arthritis of the elbow requires antibiotic treatment and often surgical drainage. It is characterized by heat, swelling, warmth, redness, and pain, with limited range of motion of the elbow joint. Septic arthritis is often associated with fever, sweats, and chills.

Tumors

Bone tumors of the elbow joint are rare. Primary bone cancer can occur. It can be painless or associated with pain in the elbow joint. It is usually detectable by x-ray testing. Nuclear medicine bone scanning can also be helpful for detection.

Ulnar Nerve Entrapment

The ulnar nerve is the "funny bone" nerve which travels between the tip of the elbow and the inner elbow bone. At this site it can be "pinched" by normal structures or swollen structures after injury. This pinching is referred to as entrapment. When ulnar nerve entrapment occurs, numbness and tingling of the little and ring finger of the hand may be felt. Pain may occur in the entire forearm, usually the inner side. Hand dexterity can be affected. Sometimes, the numbness is reproduced by elevating the hand. Treatment consists of avoiding repeated trauma or pressure to the elbow area and resting the elbow joint. Occasionally, ice can help. In severe cases, surgical repositioning of the ulnar nerve can be required. This relocates the ulnar nerve to a position where it will not be continually compressed by the surrounding structures.

Elbow Pain at a Glance

• The elbow joint is the area of union of three long bones.
• Tendinitis can affect the inner or outer elbow.
• Treatment of tendinitis includes ice, rest, and medication for inflammation.
• Bacteria can infect the skin of the scraped (abraded) elbow.
• The "funny bone" nerve can be irritated at the elbow to cause numbness and tingling of the little and ring fingers.

WebMD Medical Reference from MedicineNet