Tennis elbow is a painful and irritable condition affecting the tendons that attach at the common extensor origin of the lateral elbow. It’s medically known as lateral epicondylalgia, and it is also commonly referred to as an extensor tendinopathy.
What Muscles are involved?
As mentioned this condition involves the extensor forearm tendons that attach into the lateral epicondyle of the elbow. The extensor Carpi Radialis Brevis (ECRB) is the most commonly affected tendon.
How would you diagnose it?
- Pain on Gripping (& weakness/poor endurance noted when using a dynamometer)
- Pain on resisted wrist & middle finger extension (muscle testing)
“patients usually report pain with picking up or gripping objects and this is because as we grip our wrist naturally goes into extension.”
- Tenderness on palpation of the “common extensor tendon” or with an insertional tendinopathy tenderness over the insertion into the lateral epicondyle
- Weak &/or tight forearm muscles
Poor biomechanics associated with the shoulder, shoulder blade and posture are often noted (weak rotator cuff muscles can cause scapular dyskinesis, over gripping and thus overactivity in the wrist extensors leading to symptoms).
What causes a Tennis Elbow?
- It is usually caused by recent or rapid changes in activity levels, an increase in training load or an increase in the amount of force/load the muscles can tolerate.
- Symptoms will often become present after activities involving repeated wrist extension or prolonged gripping which the patient does not normally perform. E.g. manual or repetitive tasks at home, in the garden or in the office.
- Poor technique when relating to exercise, or a change in duties or equipment used during domestic activities, sport, or work.
- Poor fitting equipment or equipment that’s too heavy may lead to continual maximal gripping – like tennis rackets that are too heavy or have a wide grip. Sometimes tennis strings can be too tight causing increased vibration and stress to the common extensor tendon.
“Tennis elbow has the highest incidence between the ages of 40 and 60 years and affects between 1-3% of the population.”
What Clinical Equipment/Devices can help diagnose a Tennis Elbow?
In our clinic we use both handheld dynamometers and our AxIT strength testing equipment to both diagnose Tennis Elbow, and also help our patients track their progress with rehabilitation. Our AxIT force plates and push/pull dynamometers can assess strength, endurance, and power of specific muscle groups. It assesses and analyses muscle force production patterns during functional movements.
Grip strength is tested using our handheld dynamometer. We do this test with our elbow bent by our side at 90⁰ and with our arm extended at 90⁰ shoulder flexion. Simply squeeze the dynamometer and get a reading in pounds or kilograms assessing grip strength. This is compared to the non-affected side. This test tell us if grip is something that we need to train. We can also do a hold for time to test grip endurance.
Push-It: Wrist extension strength
Isometrically testing wrist extension can inform us of both muscle strength, force production and endurance and is compared to the other side. This test is typically performed in sitting with the elbow bent to 90⁰ and the wrist in neutral. Simple extend your wrist into the Push-It device isometrically. This test will often elicit pain and weakness will be noted in patients suffering from an extensor tendinopathy and with rehab we can monitor improvement.
Pull IT: Shoulder External rotation strength
When there is weakness in the external rotator cuff muscles of the shoulder, the forearm extensors become overactive as we try to the extensors to “help out”. This is a common cause of tennis elbow. We use the Pull-It device to determine the muscle strength, force production and endurance and can do this in varying positions to truly test out if there is weakness though range of motion as we lift above head.