Ultrasound Therapy For Bursitis

Introduction

Bursitis is a condition affecting the fluid-filled sacs that cushion the joints and can result in pain and restriction of movement.¹ One potential treatment is using ultrasound waves generated by a machine over the affected joint.

These waves produce heat and vibrations in the affected area, which help relieve pain and promote healing.² This article provides an overview of bursitis, information on ultrasound therapy, and a summary of the evidence supporting the use of ultrasound therapy for bursitis.

Background

What is bursitis?

Bursae (bursa singular) are fluid-filled sacs that are present in joints to reduce the friction between the bones, muscles, and tendons that are moving. There are over 150 bursae in the body at the joints (shoulders, knees, hips etc). 

Bursitis is the condition where the bursas become inflamed. The main symptoms of bursitis are pain and restriction of movement of the joint. In some cases, pain can be mild and managed with over-the-counter painkillers. In severe cases, pain can be intolerable and can affect the quality of life.¹ Bursitis can affect people of all ages and genders, although the most common age of onset is between 30 and 60 years old.²

Causes of bursitis

The most common cause of bursitis is overuse or prolonged pressure. Individuals in professions involving significant manual labour are at risk of developing bursitis, as are professional athletes and dancers whose training involves repetitive motions at high intensity. Overuse can also result from remaining in one position for extended periods, such as sitting on hard surfaces for long durations or resting elbows on a desk, which presses the bursae against bony prominences and can lead to inflammation. Obese individuals are also at higher risk due to the added strain on their joints.¹

The second most common cause of bursitis is acute trauma or injury, which can inflame the bursae. Systemic inflammatory disorders, such as rheumatoid arthritis, lupus, or gout, can also lead to bursitis by causing inflammation in various parts of the body over extended periods.¹

Infective vs non-infective bursitis

Bursitis can be categorized based on the presence of an associated infection. An infection can occur when bacteria enter the bursa, either through a puncture wound or from an infection elsewhere in the body that spreads to the bursa, which can also happen during an invasive medical procedure. This is known as infective or septic bursitis. 

Non-infective bursitis, on the other hand, occurs in the absence of an infection. 

Both infective and non-infective types of bursitis can show similar symptoms such as pain during movement or palpation of the joint and potential movement restrictions. If there has been some trauma or injury, there may be signs of this too. The only definitive way to diagnose infective vs. non-infective bursitis is through a blood test. In some cases, fluid from the bursa may be analyzed by inserting a needle into the bursa to collect a sample.³

Treatment options for bursitis

In the case of infective or septic bursitis, the treatment will involve antibiotics to resolve the infection. Which antibiotic is given will depend on the bacteria that is causing the infection. In the majority of cases, the responsible bacteria is Staphylococcus aureus.³

The treatment for non-infective bursitis is usually supportive, i.e. does not directly target the inflamed bursa, but helps with symptom relief. In most cases, bursitis will resolve by itself without any treatment. If this does not work, other conservative measures like taking painkillers such as ibuprofen, which is part of a group of drugs called NSAIDs (non-steroidal anti-inflammatory drugs) can provide symptom relief.

However, simply taking painkillers and not attempting to heal the joint is not the solution.¹
Other measures to aid with symptom relief include resting the joint and using hot or cold packs against the painful area. These measures can be done at home and can resolve the pain within a few weeks.⁴

Physiotherapy exercises are also a common mode of treatment which can strengthen the muscles around the affected joint. For certain selected cases, injecting the joint with a steroid can help to reduce inflammation and alleviate pain for a temporary time.

Steroid injections are, however, not recommended for every joint and even if it is given, the effects are not permanent. Surgery is generally the last resort, and usually only tried after the previous options have been tried and failed.¹

Ultrasound therapy for bursitis

What is ultrasound therapy?

Ultrasound therapy involves the use of ultrasound waves, a type of sound wave that is inaudible to the human ear and typically ranges between 1 and 3 megahertz.⁵ A device that generates ultrasound waves is applied to the skin, allowing the waves' vibrations to penetrate from the skin to the joint. The goal is to create disruption and generate heat in the affected area.

The science behind this is that the generated heat aids in pain relief while the vibrations promote cell repair by enhancing blood circulation, stimulating cell growth and activity, and activating the body's immune cells to target the area. This helps to activate the body’s immune cells to target the inflamed area increasing repair and the breakdown of inflammatory products that have accumulated in the joint.²

The main advantages of ultrasound therapy are that it is completely non-invasive and does not expose the patient to any radiation (unlike an x-ray).¹ Additionally, it is of low risk for causing any harm.⁷

In practice, ultrasound therapy is typically administered by a health professional, such as a physiotherapist. The patient is positioned comfortably, and a gel is applied to the affected area. The physiotherapist then runs the ultrasound machine over the area, adjusting the frequency based on the depth of the affected tissues. Each session usually lasts around 10 minutes and is typically conducted over several sessions.¹

It is important to note that ultrasound therapy is different from ultrasound-guided injections. Ultrasound-guided bursal injections involve the use of an ultrasound scan during the injection process. This allows the clinician to visualize the joint in real time, ensuring the needle is accurately placed in the correct location.⁸

Does it work?

The evidence regarding ultrasound therapy for bursitis is conflicting and limited, with studies often involving small sample sizes. Cochrane Reviews, known for their rigorous standards in medical evidence, have evaluated ultrasound therapy for various conditions.

For instance, a review on ultrasound therapy for non-specific low back pain found insufficient evidence to support its effectiveness in reducing pain or improving range of motion.⁹ Another article also reported disagreement within the evidence on whether or not there was any therapeutic effect of ultrasound therapy.²

One main source of evidence on bursitis is a clinical trial from 1986, which is highly cited in the field although it was conducted almost 40 years ago. This trial compared the effectiveness of ultrasound therapy, NSAIDs (like ibuprofen), and physiotherapy exercises for treating bursitis and found no significant difference in outcomes between treatments with or without ultrasound therapy when combined with NSAIDs and physiotherapy.⁸

On the other hand, other relevant studies do support the use of ultrasound therapy, although not specifically for bursitis but for similar conditions.

One study which is considered high-quality evidence (a systematic review) was on adhesive capsulitis aka ‘frozen shoulder’. This condition affects the entire shoulder area and not just one part of the joint. Here, a significant improvement after using ultrasound therapy was found when compared to other non-invasive, conservative methods of pain relief.⁹

Another study looked at tendinitis (inflammation of a tendon) of one part of the shoulder and also found that ultrasound therapy along with massage was more beneficial in reducing pain and improving the range of motion as compared to cryotherapy.¹⁰

Summary

The evidence on ultrasound therapy for bursitis is limited and conflicting regarding its effectiveness on the joint. It is typically not used as a standalone treatment but rather in conjunction with other therapeutic methods. While ultrasound therapy shows promise, further research is necessary to establish definitive conclusions.