What Is Extensor Tendonitis?

krisanapong detraphiphat / Getty Images
krisanapong detraphiphat / Getty Images

Medically reviewed by Laura Campedelli, PT, DPT

Extensor tendonitis (also spelled tendinitis) is inflammation of tendons on the top of your hands and feet. These tendons attach to muscles that straighten your fingers and lift up your toes and the top of your foot. This condition often results from the overuse of these muscles, but it can also develop from wearing tight shoes.

This article discusses extensor tendonitis—what it is, its potential causes, how it is diagnosed, and its treatment options.

krisanapong detraphiphat / Getty Images
krisanapong detraphiphat / Getty Images

Types of Extensor Tendonitis

Tendonitis can develop in any tendon of the extensor muscles. These tendons are long, thin bands of tissue you can feel on the top of your hands and feet. These structures attach to muscles in the forearm and lower leg on one end and bones of the fingers and toes on the other.

The extensor tendons in the hands that attach to these muscles include:

  • Extensor digitorum communis: Straightens the index, middle, ring, and small fingers

  • Extensor digiti minimi: Straightens the small finger

  • Extensor indicis proprius: Straightens the index finger

  • Extensor pollicis longus and extensor pollicis brevis: These muscles move the thumb into a "thumb's-up" position

Extensor tendons on the top of the foot attach to these muscles:

  • Extensor digitorum longus and extensor digitorum brevis: These muscles lift the second, third, fourth, and fifth toes

  • Extensor hallucis longus: Lifts up the big toe

Chronic tendon pain can lead to a condition called tendinopathy. Though tendonitis results from inflammation, tendinopathy is the degeneration—or micro-tearing—of a tendon that occurs with long-term overuse. It's important to know which condition you are dealing with because they require different treatments.

Related:Tendonitis and Tendinopathy

Symptoms of Extensor Tendonitis

The primary symptom of extensor tendonitis is pain in the affected tendon(s). You might also experience swelling, and your skin might become red or warm to the touch.

You can feel pain from extensor tendonitis when you use the affected muscles or when you move your hand or foot in the opposite direction and stretch the tendons out.

Typically, pain from tendonitis gets worse when you're using the affected muscles and improves with rest.

What Causes Extensor Tendonitis?

Extensor tendonitis in the hands typically results from the overuse of your extensor muscles, causing inflammation in your tendons. However, it can also result from trauma, such as falling on your hand or an injury during sports activities.

Extensor tendonitis can occur with activities such as:

  • Typing

  • Using a computer mouse

  • Gymnastics

  • Weightlifting

  • Manual labor jobs

  • Playing a musical instrument

Extensor tendonitis in the foot can also result from activities that overuse it, such as running (especially uphill). However, it can also occur from wearing shoes that are too tight, or tightly laced shoes—commonly worn for running, dancing, and ice skating.

Less common causes of tendonitis include:

  • Infection

  • Side effects of medication

  • Joint deformities

  • Medical conditions, such as diabetes or arthritis

How Do Healthcare Providers Diagnose Tendonitis?

Diagnosis of tendonitis is often possible with a physical exam and a review of your symptoms. However, your healthcare provider might order additional tests to rule out more serious injuries, such as a broken bone or torn tendon.

Imaging tests can include:

Treatment Options for Extensor Tendonitis

Extensor tendonitis usually gets better with conservative treatment, such as medication, home remedies/activity modification, and physical therapy.

Medications

You can treat inflammation from tendonitis with non-steroidal anti-inflammatory drugs (NSAIDs) such as:

  • Motrin, Advil (ibuprofen)

  • Aleve (naproxen)

  • Bayer (aspirin)

Other medications, such as Tylenol (acetaminophen) can help reduce pain from this condition.

In some cases, you might need prescription anti-inflammatory medications (such as corticosteroids) or pain relievers in the short term.

Home Remedies and Activity Modification

Home treatment for tendonitis should follow the RICE protocol:

  • Rest: Avoid any activities that increase your pain. If you can't avoid them completely, take frequent breaks to allow your muscles to relax.

  • Ice: Apply ice to your hand or foot several times per day for up to 20 minutes at a time. Use a bag of ice cubes or a commercial ice pack. Place a towel between the ice pack and your skin for protection.

  • Compression: Wrap your foot or hand in an elastic bandage or soft splint to help support the injured tendons and reduce swelling.

  • Elevation: If your hand or foot is swollen, elevate it above the level of your heart when you are resting.

Modifying your activities can also address the underlying cause of your tendonitis. Hand extensor tendonitis can develop from poor positioning. Setting up an ergonomic workstation can help significantly.

Consult with your coach or a personal trainer if your tendonitis is related to exercise. You might need to adjust your technique or training schedule to decrease pressure on your tendons.

Physical Therapy

Extensor tendonitis—both in the hand and foot—is often treated with physical therapy. A physical therapist can help determine the underlying cause of your condition and provide you with an individualized treatment program.

Interventions physical therapists practice to treat tendonitis can include:

  • Pain-reducing modalities (ultrasound, electrical stimulation, laser therapy)

  • Manual therapy

  • Exercise programs

  • Prescription of orthotics (such as a hand splint, or shoe insert)

A Certified Hand Therapist—a healthcare provider who specializes in hand conditions— can also treat extensor tendonitis in the hand.

Surgery

Surgery is not a typical treatment for extensor tendonitis unless the tendon is torn. Recovery after extensor tendon repair requires physical therapy, and treatment follows a specific protocol.

Prognosis

Extensor tendonitis can take weeks or even months to improve. Early diagnosis and treatment are key for a quicker recovery. It's important to determine the underlying cause of your condition rather than just treating your symptoms. See your healthcare provider if you suspect you might have extensor tendonitis.

Summary

Extensor tendonitis is a condition that is characterized by inflammation of tendons on the top of the feet or hands. This condition causes pain and swelling. Tendonitis symptoms worsen with activity and often improve with rest. Treatment for extensor tendonitis includes medications, home remedies/activity modification, and physical therapy. This condition does not usually require surgery.