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.

Surgical Shoulder Procedures

Distal Clavicle Excision (Mumford Procedure)

Get Clear, Concise Answers to Your Top Questions About Distal Clavicle Excision (Mumford Procedure)

In this patient-friendly guide, we answer the top 15 questions about distal clavicle excision, commonly known as the Mumford procedure. Learn what to expect during surgery, how to manage pain, and tips for a successful recovery.

Q1. What is a distal clavicle excision, and what is the Mumford procedure?

A distal clavicle excision, also known as the Mumford procedure, is a surgical operation that involves removing a small portion (typically 8 to 10 millimeters) of the outer end of the collarbone (clavicle) where it meets the shoulder blade. This creates extra space in the joint, stopping the bones from rubbing against each other and relieving pain.

Q2. What is the acromioclavicular (AC) joint, and how does it cause shoulder pain?

The acromioclavicular (AC) joint is the junction at the top of the shoulder where the collarbone (clavicle) connects to the acromion, which is the bony tip of the shoulder blade. Over time, wear and tear, repetitive overhead use, or injuries can cause the cartilage between these bones to wear down, leading to bone-on-bone friction, inflammation, bone spurs, and significant pain.

Q3. What conditions are treated with a distal clavicle excision?

This procedure is primarily used to treat:

AC Joint Osteoarthritis: Age-related wear and tear of the joint cartilage.
Distal Clavicle Osteolysis: Softening or resorption of the end of the collarbone, often caused by repetitive heavy lifting (weightlifter's shoulder).
Post-Traumatic Arthritis: Damage to the joint resulting from a past separation or fracture.
Impingement Syndrome: Bone spurs on the AC joint that pinch the underlying rotator cuff tendons.

Q4. How is the Mumford procedure performed?

The surgery is usually performed arthroscopically (using a small camera and tiny instruments inserted through small incisions). During the procedure, the surgeon inspects the shoulder joint, cleans out damaged tissue, and uses a specialized burr to shave away the worn-out end of the collarbone. In some cases, it may be performed through a small open incision if other procedures are being done at the same time.

Q5. What are the benefits of the arthroscopic approach compared to open surgery?

The arthroscopic approach offers several advantages:

Smaller incisions and less scarring.
Less damage to the surrounding muscles and ligaments.
Reduced pain after the operation.
A faster recovery and rehabilitation process.

Q6. What type of anesthesia is used for this surgery?

Most patients receive a combination of general anesthesia (which puts you to sleep) and a regional nerve block. The nerve block numbs the nerves in your shoulder and arm, providing excellent pain relief for 12 to 24 hours after the procedure, which helps reduce the need for strong pain medications immediately after surgery.

Q7. How long does the surgery take, and will I need to stay in the hospital?

The surgery itself usually takes about 30 to 45 minutes. It is performed as an outpatient procedure, meaning most patients can go home the same day, once the anesthesia wears off and it is safe to travel.

Q8. What are the potential risks and complications of a distal clavicle excision?

While the Mumford procedure is very safe, any surgery carries some risks. These include:

Infection or bleeding.
Numbness around the incision site.
Continued shoulder pain or stiffness.
Incomplete bone removal, which may require revision.
Minor instability of the AC joint if too much bone is removed.

Q9. How is pain managed immediately after surgery?

Pain is managed using a combination of methods:

Nerve Block: Numbs the shoulder for the first day.
Oral Medications: Prescribed pain relievers and anti-inflammatory drugs.
Ice Therapy: Applying ice packs for 20 minutes at a time to reduce swelling.
Rest: Limiting arm movement and keeping the shoulder supported.

Q10. How long will I need to wear a sling after the procedure?

You will typically wear a sling for comfort and protection for about 1 to 2 weeks. Unlike rotator cuff repair, the bone removal itself does not require long-term immobilization to heal. You can usually remove the sling for light daily activities, showering, and structured exercises as directed by your surgeon.

Q11. How should I sleep after the surgery?

Sleeping can be challenging in the first few weeks. To sleep more comfortably:

Sleep in a semi-upright position in a recliner chair or propped up with pillows in bed.
Place a pillow behind your elbow or under your arm to prevent your shoulder from falling backward.
Avoid sleeping directly on your stomach or on the side that was operated on.

Q12. When can I return to normal daily activities like driving and showering?

Most patients can return to light daily tasks within a few days to a week. You can shower once your incisions are dry and closed, typically 3 to 5 days after surgery, keeping the incisions covered. You should not drive while taking prescription pain medications or while your arm movement is significantly restricted.

Q13. When does physical therapy start, and what does it involve?

Physical therapy typically begins within the first 1 to 2 weeks after surgery. The rehabilitation program includes:

Phase 1 (Weeks 1-2): Gentle passive range-of-motion exercises to prevent stiffness.
Phase 2 (Weeks 2-6): Active movements to restore full shoulder mobility.
Phase 3 (Weeks 6+): Progressive strengthening exercises for the shoulder and surrounding muscles.

Q14. What is the recovery timeline for returning to work and sports?

The timeline depends on your activity level:

Desk Jobs: 1 to 2 weeks.
Light Lifting/Light Manual Work: 4 to 6 weeks.
Heavy Manual Labor & Weightlifting: 3 to 4 months.
Overhead Sports (Tennis, Swimming): 3 to 4 months.

Q15. What are the long-term results and success rates of the Mumford procedure?

The long-term success rate of the Mumford procedure is very high, with over 85% to 90% of patients experiencing significant pain relief and improved shoulder function. Once the bone-on-bone rubbing is eliminated and the joint heals, most patients can return to their previous activities without chronic pain.

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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