What is Quadrilateral Space Syndrome (QSS)?

Quadrilateral Space Syndrome (QSS) is a rare condition that occurs when the axillary nerve and/or the posterior circumflex humeral artery get squeezed or compressed as they pass through a small area in the back of your shoulder called the 'quadrilateral space.' This compression can lead to pain, numbness, tingling, and weakness in your arm.

QSS is often caused by repetitive overhead activities, common in athletes like throwers, swimmers, and tennis players. It can also result from repeated motions that narrow the space (overuse), extra bands of tissue that can form and compress the nerve or artery (fibrous bands), trauma or injury such as a shoulder dislocation or a direct blow to the shoulder which can cause swelling or scar tissue, or muscle enlargement if muscles in the area grow significantly (e.g., in bodybuilders), they can crowd the space.

What are the common symptoms of QSS?

Symptoms typically include vague pain or a dull ache in the back of the shoulder, sometimes radiating down the arm; numbness, tingling, or a 'pins and needles' sensation in the shoulder and upper arm; pain that worsens with overhead movements or when your arm is in a 'throwing' position; tenderness when pressure is applied over the back of the shoulder in the quadrilateral space; weakness or fatigue in the arm, especially when lifting or rotating it; and sometimes, shrinking (atrophy) of certain shoulder muscles like the teres minor or deltoid.

How is QSS diagnosed?

Diagnosing QSS can be challenging because its symptoms can be similar to other shoulder problems. Your doctor will ask about your symptoms, activities, and any past injuries; perform a physical examination to check your shoulder's range of motion, strength, sensation, and tenderness; may order imaging tests like MRI or ultrasound to look at the quadrilateral space, assess muscle size, and check for any abnormalities or scarring. In some cases, nerve conduction studies (NCS) or electromyography (EMG) might be performed to evaluate how well the axillary nerve is working. An injection of local anesthetic into the quadrilateral space that temporarily relieves your symptoms can also help confirm the diagnosis.

What are the non-surgical treatment options?

Most cases of QSS improve with non-surgical treatment. These options focus on reducing pressure on the nerve and artery, managing pain, and restoring function: rest and activity modification (avoiding or modifying activities that worsen your symptoms, especially overhead movements); anti-inflammatory medications (over-the-counter or prescription NSAIDs like ibuprofen can help reduce pain and inflammation); ice or heat packs (applying ice can help reduce pain and inflammation, especially after activity, heat can help relax muscles); physical therapy (a physical therapist will guide you through exercises to maintain or improve shoulder range of motion and flexibility, strengthen the muscles around your shoulder to provide better support, improve posture and body mechanics); and corticosteroid injections (in some cases, your doctor may suggest an injection of corticosteroid medication into the area to reduce inflammation and pain).

When is surgery considered for QSS?

Surgery is usually considered if non-surgical treatments haven't significantly improved your symptoms after about six weeks or more; symptoms are severe or progressively worsening; or there's clear evidence of nerve damage or significant compression.

What does the surgical procedure involve?

The goal of surgery, called decompression, is to relieve pressure on the axillary nerve and posterior circumflex humeral artery. This typically involves making a small incision at the back of your shoulder; identifying the compressed nerve and artery; carefully removing or cutting any fibrous bands, scar tissue, or other abnormal structures that are causing the compression. The procedure is designed to free up the nerve and artery, allowing them to function normally.

What are the potential risks of surgery?

As with any surgery, there are potential risks, though QSS surgery is generally safe. These can include infection, bleeding, damage to surrounding nerves or blood vessels, scarring, persistent pain or incomplete relief of symptoms, and reaction to anesthesia. Your surgeon will discuss these risks with you in detail.

What do I need to do before surgery?

Your healthcare team will provide specific instructions, but generally, you may need to undergo a pre-operative physical examination and blood tests; stop certain medications (e.g., blood thinners, some anti-inflammatory drugs) a week or two before surgery; arrange for someone to drive you home after surgery and help you during the first few days of recovery; and avoid eating or drinking for a certain period before the surgery.

What can I expect immediately after surgery?

You will likely have your arm in a sling to help it rest and heal. You may experience some pain, which will be managed with medication. Your surgical site will be covered with a dressing. Your surgeon will give you instructions on wound care and activity restrictions.

How long is the typical recovery period?

Recovery times vary for each person, depending on the severity of the condition and how long the nerve was compressed. First few weeks (0-2 weeks): Focus on rest, pain management, and protecting the surgical site. Gentle elbow and wrist movements will be encouraged. Weeks 2-6: You will start physical therapy, focusing on gentle range-of-motion exercises for your shoulder. After 6 weeks: As healing progresses, your physical therapist will introduce strengthening exercises to rebuild muscle strength. Overall, it can take several weeks to months to feel significant improvement, as nerve healing is a slow process.

What does rehabilitation/physical therapy involve?

Physical therapy is crucial for a successful recovery. Your therapist will design a personalized program that may include pain and swelling management (using ice, gentle massage, or other techniques); range of motion exercises (to restore full movement in your shoulder); strengthening exercises (targeting the muscles around your shoulder, including the deltoid and teres minor, which may have been weakened); postural correction (to improve overall shoulder mechanics); and activity-specific training (gradually reintroducing movements related to your work, sports, or daily activities).

How will pain be managed?

Your doctor will prescribe pain medication to help manage discomfort after surgery. This may include prescription pain relievers (e.g., opioids for a short period); over-the-counter pain relievers (e.g., acetaminophen, ibuprofen) as recommended by your doctor. You may also use ice packs to reduce localized pain and swelling.

When can I expect to return to daily activities, work, driving, and sports?

This timeline varies greatly based on your recovery progress and the demands of your activities. Daily activities: Light daily activities can usually be resumed within a few days to weeks. Driving: You can typically drive once you are no longer taking strong pain medications and have sufficient control and range of motion in your shoulder to safely operate a vehicle (often a few weeks after surgery). Work: Return to work depends on the nature of your job. Light, desk-based work might be possible within a few weeks, while jobs requiring heavy lifting or repetitive overhead movements will take longer, potentially several months. Sports: A gradual return to sports, especially overhead activities, will be guided by your physical therapist and surgeon, often not for several months after surgery. Full return to competitive sports may take 3-6 months or longer.

What is the expected long-term outcome?

For many patients, surgical decompression of QSS provides significant relief from pain, numbness, and weakness, allowing them to return to their normal activities, including sports. Nerve healing can be slow, so improvement may continue for several months. While some mild symptoms may occasionally linger, the goal is to significantly improve your quality of life and shoulder function.

Non-Surgical Shoulder Treatment Options

Shockwave Therapy for Calcific Tendinitis

Get Clear, Concise Answers to Your Top Questions About Shockwave Therapy for Calcific Tendinitis

Learn how Extracorporeal Shockwave Therapy (ESWT) works, what to expect during treatment, and how it helps dissolve painful calcium deposits in the shoulder without surgery.

Q1. What is Shockwave Therapy, and how does it treat calcific tendinitis of the shoulder?

Shockwave therapy, also known as Extracorporeal Shockwave Therapy (ESWT), is a non-surgical treatment that uses high-energy sound waves to treat painful shoulder conditions like calcific tendinitis. When these gentle but powerful acoustic waves are directed at the injured area, they stimulate blood flow, accelerate the body's natural healing process, and help break down painful calcium deposits that have formed in your shoulder tendons.

Q2. What is calcific tendinitis, and why does it form in the shoulder?

Calcific tendinitis is a condition where small calcium deposits build up inside the tendons of your rotator cuff (most commonly the supraspinatus tendon). The exact cause of these deposits isn't fully understood, but they are thought to develop due to wear and tear, repetitive stress, reduced blood supply to the tendon, or natural aging. These chalk-like deposits can cause significant pressure, inflammation, and sharp pain when you move your arm.

Q3. How does shockwave therapy actually break down calcium deposits?

The acoustic waves delivered during shockwave therapy create mechanical stress on the hard calcium deposits. This mechanical energy helps soften and fragment the calcifications into tiny particles. Once broken down, your body's immune system and blood circulation naturally absorb and clear away these fragments over the following weeks, relieving the pressure and pain inside the tendon.

Q4. What happens during a typical shockwave therapy session?

During your session, you will sit or lie down comfortably. A healthcare provider will apply a warm, clear gel to your shoulder to help conduct the sound waves. They will then place the handheld shockwave device against your skin over the painful area. The device is activated, emitting clicking sounds as it delivers waves into the tissue. The provider will slowly move the device around to target the calcium deposits.

Q5. Does shockwave therapy for calcific tendinitis hurt?

You may feel some discomfort, pressure, or a deep throbbing sensation during the treatment, but it is generally well-tolerated. The intensity of the shockwaves can be adjusted based on your comfort level. The treatment starts at a lower setting and is gradually increased as you get used to the sensation. Most patients find that the discomfort resolves immediately after the session ends.

Q6. How many treatment sessions will I need?

Most patients require a series of 3 to 5 sessions, usually spaced about one week apart. This spacing allows your shoulder tissues time to heal and respond to the stimulation between treatments. Your doctor will assess your progress and determine the exact number of sessions needed based on the size of the deposit and your response.

Q7. How long does each shockwave therapy session take?

The actual application of the shockwaves takes only about 10 to 15 minutes. With preparation and positioning, your entire appointment will typically last 20 to 30 minutes, making it a highly convenient option that fits easily into a busy schedule.

Q8. What are the main benefits of choosing shockwave therapy over surgery?

Shockwave therapy offers several major advantages over surgical options:

It is entirely non-invasive, meaning there are no incisions, stitches, or scars.
It requires no anesthesia, avoiding associated risks.
There is virtually no downtime, allowing you to return to light daily activities immediately.
It has a very low risk of infection or other surgical complications.

Q9. Are there any side effects or risks associated with shockwave therapy?

Side effects are rare and generally mild. Some patients experience temporary redness, mild swelling, bruising, numbness, or a temporary increase in soreness in the treated area for a few days. These symptoms are normal signs of the body's inflammatory healing response and typically resolve on their own within 2 to 5 days.

Q10. Who is a good candidate for shockwave therapy?

Good candidates are patients diagnosed with calcific tendinitis who have had pain for at least three months and have not found relief with initial conservative treatments like rest, ice, anti-inflammatory medications, or physical therapy. It is not recommended for pregnant women, individuals with blood clotting disorders or taking blood thinners, patients with active infections, or those with cardiac pacemakers.

Q11. What is the success rate of shockwave therapy for calcific tendinitis?

Clinical studies show that shockwave therapy is highly effective, with success rates ranging from 70% to 85% in reducing pain and improving shoulder mobility. X-rays taken after treatment often show significant reduction or complete disappearance of the calcium deposits within a few months of completing the therapy.

Q12. What should I do or avoid doing immediately after a treatment session?

After a session, you can return to your normal daily activities, but you should avoid strenuous heavy lifting, high-impact exercise, or intense shoulder workouts for 48 hours. We also advise against using ice or taking anti-inflammatory medications (like ibuprofen) immediately after treatment, as these can interfere with the beneficial inflammatory response that shockwave therapy stimulates to heal the tendon.

Q13. How long does it take to see improvements and feel pain relief?

Some patients feel immediate, temporary pain relief due to a numbing effect from the shockwaves. However, the true healing process takes time. Most patients start noticing a lasting reduction in pain and improved range of motion about 4 to 6 weeks after their final session, with improvements continuing for up to 3 months.

Q14. Can I continue doing physical therapy or exercises during my treatment?

Yes, shockwave therapy is often combined with a structured physical therapy or home exercise program. Gentle stretching and strengthening exercises help maintain your shoulder's range of motion, improve muscle function around the joint, and support the long-term recovery of the tendon. Always consult your therapist to ensure your exercises align with your treatment schedule.

Q15. What are my options if shockwave therapy does not resolve the calcium deposits?

If shockwave therapy does not provide sufficient relief, other options include ultrasound-guided barbotage (a procedure where the calcium is washed out using a needle) or a minimally invasive arthroscopic surgical procedure to remove the calcium deposits and repair any associated damage to the tendon. Your orthopaedic specialist will discuss these alternatives to help you find the best path forward.

We encourage you to write down any specific questions you have and discuss them thoroughly with your surgeon, doctor, or physical therapist. They are your best resource for personalized advice and care.

Disclaimer: This brochure provides general information and is not a substitute for professional medical advice. Always consult your doctor or qualified healthcare provider with any questions you may have regarding your specific medical condition and treatment plan.

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