Aetiology
With tennis elbow, the common extensor tendon origin at the lateral epicondyle of the humerus is irritated, inflamed, damaged and potentially torn. Men and women are equally affected and there are two typical patterns of occurrence: as an acute onset typically seen in young athletes, and as a chronic condition seen in older people.

Those tennis players with harder, more forceful serves feel gradually worsening pain after ten to twenty serves have been hit. The stress on the elbow can be great due to the centripetal force applied to it. This force can, over a short period of minutes, develop into the specific problem known as tennis elbow.

The exact cause of tennis elbow is not known, but it does tend to occur after repetitive use of the Extensor Carpi Radialis Brevis (ECRB) tendon, such as in tennis (hence the name). The ECRB tendon is involved in extending the wrist joint and is also active when gripping with the wrist extended (as in tennis). Any activity that twists and extends the wrist can lead to tennis elbow.

Presentation
The first sign of tennis elbow is usually tenderness and pain when pressure is applied to the outside of the elbow. If left untreated, a dull constant pain or sharp shooting pain can be felt. Swelling may be present. Other symptoms include:
• Pain when the wrist or hand is straightened
• Pain felt when lifting a heavy object
• Pain when making a fi st or shaking hands
• Shooting pains from the elbow down to the forearm or up into the upper arm

Pain with tennis elbow is typically localised over the bony bump on the outside of the elbow (lateral epicondyle) and may extend down to the hand. This area is usually very tender to touch. Rest usually relieves the pain. Sometimes other conditions that are not linked to tennis elbow can cause pain in the elbow. For example, arthritis of the elbow, a pinched nerve in the neck, shoulder impingement and carpal tunnel syndrome.

Treatment
The type and duration of the treatment will depend on the severity of the condition. The fi rst step in treating tennis elbow is to eliminate the activities that cause the pain, such as tennis or golf. Pain killers and anti-inflammatory medications relieve the pain and reduce the inflammation. A tennis elbow strap can be worn just below the elbow to limit the stress on the ECRB tendon. Treating the area with an ice pack and performing an ice massage are also recommended. Physiotherapy to release the tendon inflammation and retrain the extensor muscles is important.

Conservative
Activity modification – Initially, the activity causing the condition should be limited. Limiting the aggravating activity, not total rest, is recommended. Modifying grips or techniques, such as use of a different size racket and/or use of 2-handed backhands in tennis, may relieve the problem.

Medication – anti-inflammatory medications may help alleviate the pain.

Brace – a tennis elbow brace, a band worn over the muscle of the forearm, just below the elbow, can reduce the tension on the tendon and allow it to heal.

Physical therapy - may be helpful, providing stretching and/or strengthening exercises. Modalities such as ultrasound or heat treatments may be helpful. Stretches and strengthening exercises are essential to prevent re-irritation of the tendon. Progressive strengthening for this condition involves using weights or elastic theraband to increase wrist flexion strength (grip strength). Racquet sport players also are commonly advised to strengthen their shoulder rotator cuff and scapula muscles to reduce any overcompensation in the wrist flexors in gross arm movements (such as a swing).

Steroid injections – A steroid is a strong anti-inflammatory medication that can be injected into the area. H&L can be given into the painful areas. As with any steroid injection, there is a small risk of local infection and tendon rupture. Most doctors will restrict after two injections giving further courses, as there is less likelihood of effectiveness but increased risk of side-effects. No more than three injections should be given. As opposed to short-term effects, the long term benefi ts of local steroid injection are less clearly established.

Shockwave treatment – A new type of treatment, available in the office setting, has shown some success in 50–60% of patients. This is a shock wave delivered to the affected area around the elbow, which can be used as a last resort prior to the consideration of surgery.

Surgery
Surgery is only considered when the pain is incapacitating and has not responded to conservative care, and symptoms have lasted more than six months. Conservative treatment has a reported failure rate of 5 – 30%. Surgery involves removing the diseased, degenerated tendon tissue. Two surgical approaches are available; traditional open surgery (incision), and arthroscopy – a procedure performed with instruments inserted into the joint through two small incisions. Both options are performed in the outpatient setting.

Surgical intervention
Traditionally the standard procedure for tennis elbow has been an open surgical release. This usually involves a small incision and can be performed as a day case procedure. The results of this surgery are over 90% successful.

With new arthroscopic (keyhole) techniques, the results are the same as open procedures, but with additional advantages. These include:
1. Smaller incisions, thus less post-operative pain.

2. The ability to look inside the elbow joint and treat other, associated conditions (20% of tennis elbows have a problem inside the joint, which is not seen with open surgery).

3. Only the tendon affected by tennis elbow (ECRB) is released in the arthroscopic method, as this tendon is the closest extensor tendon to the elbow joint. With the open procedure other extensor tendons are released leading to weak grip strength post-op.

4. No post-operative immobilisation and the patient has earlier return to function.

5. Earlier return to sports and work due to the keyhole method and no or little loss of grip strength.

6. Clinical results have been as good as open surgery.

The operation
The surgeon introduces an arthroscope into the elbow joint through a small 5 millimeter incision on the medial side of the elbow. Another small incision is made on the lateral side. This is used for inserting instruments. The arthroscope is used to identify the location of the ECRB tendon and identify any other problems in the elbow joint (such as loose bodies). An arthroscopic picture of the ECRB tendon of a patient with recalcitrant tennis elbow is shown in Figure 1. The tendon shows a linear tear. A small shaver is inserted and the ECRB tendon is divided (Figure 2 and 3). All other structures are avoided. Any other intra-articular pathologies e.g. loose bodies, plica, synovitis are also treated. Arthroscopic tennis elbow debridement takes about 30 minutes and is done on a day-case basis. A general anaesthetic is usually used. Patients are generally able to return to work within 1 to 2 weeks after surgery. This patient shows full active range of motion in his right elbow 2 weeks after surgery (Figure 4). This is vastly superior to traditional open surgery where patients take up to 2 months to return to work after surgery.