What is Shoulder Impingement Syndrome? | The Complete Guide

Written by on September 20, 2021 — Medically reviewed by John Doe

A patient with Shoulder impingement syndrome

Does it hurt when you raise or lower your shoulder? That’s a symptom of impingement. But, what is shoulder impingement syndrome anyway? Why does it hurt? And, how in the world did you get it?

First of all, it happens when your rotator cuff is frequently compressed under your shoulder blade. Hence, why it’s called shoulder impingement syndrome.

But, pinpointing the exact location of the pain can be frustrating. Especially since there’s tons going in and around your shoulder.

So, to better understand this topic, it’s best that you get a basic context of what makes up your shoulder.

What structures does shoulder impingement syndrome involve?

There are 3 bones that make up our shoulder:

  • Humerus, or your upper arm
  • Clavicle, or your collarbone, and
  • Scapula, or your shoulder blade

Your shoulder is also an asymmetrical ball-and-socket joint. Meaning, it allows for a great degree of movement through all planes of motion.

But, its lack of symmetry also means that it’s inherently unstable.

Luckily, your shoulder also has built-in measures to give it some much-needed stability.

First, your scapula and collarbone adapt to the movement of your upper arm.

This helps counter the asymmetry of your shoulder joint.

This movement pattern is what we call the scapulohumeral rhythm. It’s a key factor for shoulder health.

Second, your shoulder also has several ligaments and muscles.

They act as a counterbalance that helps give your joint some much-needed stability.

Worth focusing on are your rotator cuffs. Their primary function is keeping your shoulder where it needs to be. That is, apart from rotating your shoulder, of course.

Why does shoulder impingement syndrome hurt?

Well, it’s a chronic condition. Meaning, it’s happened over weeks or months of repetitive overhead movement.

The constant rubbing of your rotator cuffs irritates the soft tissue. And in turn, leads to damage and swelling of the following:

  • Rotator cuff muscles, primarily the Supraspinatus
  • Tendon of the long head of your biceps
  • Bursae surrounding your shoulder

Types of shoulder impingement syndrome

Compression can be the result of 2 things:

  1. Primary – The tip of your shoulder blade can have four different shapes. It can either be flat, curved, hooked or convex. Dependent on the shape is the amount of space underneath the scapula. The smaller the space, the higher chance of impinged tendons.
  2. Secondary – Muscle imbalance such as tightness and weakness can affect the scapulohumeral rhythm. It can lead to premature shortening of the gap underneath the shoulder blade. Repetitive overhead motion can cause compression of the tendons under the scapula.

How common is it

About 44% to 65% of shoulder complaints are classified as shoulder impingement syndrome. Of these, 54% of patients go on to report persistent symptoms even after 3 years. (1)

What does it feel like

Signs and symptoms include:

  • Night pain which can affect sleep
  • Shoulder pain when lying on affected side
  • Shoulder pain between halfway to end ranges of shoulder motion
  • Shoulder and arm weakness
  • Swelling in front or on top of your shoulder
  • Unequal shoulder height

Who is at risk

Risk factors associated with shoulder impingement syndrome are (2):

  • Overhead dominant athlete and workers
  • Greater than 50 years of age
  • Smokers
  • Hook-shaped scapula
  • Decubitus position sleepers

Diagnosis

Medical History and Physical Examination

Your doctor starts off with a detailed history of past and recent activities. He/she will then pick out what may have led to your shoulder impingement.

These include any overhead activities that you might have done for too much at a time.

Your doctor will likely also check the following:

  • Shoulder range of motion
  • Muscle strength
  • Location of the pain

Ancillary Procedures

Your doctor will likely also order an x-ray. This is to check:

  • Any bony abnormalities in your shoulder (e.g. bone spurs that may lead to narrowing of the joint space)
  • The shape of your scapula.

If your doctor wants a more detailed look, he/she might also order an MRI or ultrasound. These tests:

  • Put more focus on the integrity of your rotator cuff tendons
  • Check for possible bursitis and other soft tissue pathology

4 Non-surgical treatment options for shoulder impingement

1. Oral Medication

Commonly prescribed are non-steroidal anti-inflammatory drugs (NSAIDs) and other oral pain medications. Examples include aspirin, naproxen, and ibuprofen.

2. Corticosteroid Injection

This is another form of anti-inflammatory drug.

Irritated soft tissues injected with corticosteroids have seen pain relief. Research says this relief can last 3-6 months after injection. (3)

3. Physical Therapy

Physical therapists use a variety of modalities to decrease pain. These include:

  • Heat/ice packs
  • Shockwave therapy
  • Dry needling
  • Electrotherapy

PTs can also fix possible muscle imbalances with:

  • Progressive strengthening of the shoulder stabilizing muscles
  • Stretching and joint mobilization for improved mobility
  • Proprioceptive exercises to increase joint awareness

A recent study has shown that a supervised rehabilitation program reported a 90% functional recovery from shoulder impingement. (4)

Surgical Option – Arthroscopic Acromioplasty

If conservative treatments fail, going the surgical route may be the next best option.

Arthroscopic acromioplasty involves shaving off the excess bone on your shoulder blade.

This increases the space where the rotator cuff tendons pass through. It may lessen soft tissue irritation and swelling.

Home Remedy for shoulder impingement

At first signs and symptoms of shoulder pain, you should 

  • Avoid the activity that aggravated the pain
  •  Use an ice pack to decrease pain and swelling 
  •  Wrap with compression bandage to reduce swelling 

Recovery

Minor case of shoulder impingement can show good improvement with 2-4 weeks of physical therapy. But, for some cases, it can take around 3-6 months for the rotator cuff tendons to heal completely.

With surgery, 4 months is the expected time for full recovery. (5)

5 tips to prevent shoulder impingement syndrome

  1. Strengthening all muscles surrounding your shoulder.
  2. Warm up before any exercise
  3. Gradually build up your activities that need overhead arm movement.
  4. Adapt an ergonomically correct work place
  5. Use a stool to avoid reaching overhead.

FAQs:

What happens if shoulder impingement is left untreated?

Aside from being in pain, structurally, you may develop (1):

  • Bone spurs,
  • Frozen shoulder, and
  • Possible tearing of your rotator cuff tendons.

Being in chronic pain may also affect your mental health.

Will doing push-ups help prevent shoulder impingement syndrome?

Doing push ups alone may cause your shoulders to round forward and worsen your symptoms. (6)

But, push ups also help build strength in your chest and shoulder muscles. These same muscles also move and stabilize the shoulder.

The key here is to balance your pushups with other exercises. This way, you involve other muscles and balance out their strengths and flexibility.

Can you use KT tape on shoulder impingement?

Kinesio taping can’t alter the cause of shoulder impingement. But, it can help address symptoms.

Kinesiotaping can help decrease pain and provide support for the short term. So, use it as a complement to other forms of treatment. (7)

Will a shoulder brace help?

A recent study showed that a shoulder brace alters muscle activity during movement. (8)

This is crucial since one of the reasons for impingement is muscle imbalance. This effect, in turn, might lead to better support, proprioception, and better postural habits.

Conclusion

Knowing how your shoulder moves is important when understanding shoulder impingement syndrome.

Hopefully, what you learned here gave you a better perspective on why your shoulders hurt and how to prevent it from getting worse.

Resources

  1. Creech, Julie A. and Sabrina Silver. “Shoulder Impingement Syndrome.” StatPearls, StatPearls Publishing, 26 July 2021. https://pubmed.ncbi.nlm.nih.gov/32119405/
  2. Tangtrakulwanich, Boonsin, and Anucha Kapkird. “Analyses of possible risk factors for subacromial impingement syndrome.” World journal of orthopedics vol. 3,1 (2012): 5-9. doi: 10.5312/wjo.v3.i1.5
  3. Garvey, Kirsten & Solberg, Muriel & Cai, Andrew & Matzkin, Elizabeth. (2018). Efficacy of corticosteroid injection for subacromial impingement syndrome. Annals of Joint. 3. 62-62. 10.21037/aoj.2018.07.01. https://aoj.amegroups.com/article/view/4450/5066
  4. Gomora-García, Mónica et al. “Efectividad de los medios físicos en el síndrome de abducción dolorosa de hombro” [Effectiveness of physiotherapy on painful shoulder impingement syndrome]. Cirugia y cirujanos vol. 84,3 (2016): 203-7. DOI: 10.1016/j.circir.2015.08.007
  5. Altchek, D W et al. “Arthroscopic acromioplasty. Technique and results.” The Journal of bone and joint surgery. American volume vol. 72,8 (1990): 1198-207. https://pubmed.ncbi.nlm.nih.gov/2398090/
  6. Alizadehkhaiyat, Omid et al. “POSTURAL ALTERATIONS IN PATIENTS WITH SUBACROMIAL IMPINGEMENT SYNDROME.” International journal of sports physical therapy vol. 12,7 (2017): 1111-1120. doi: 10.26603/ijspt20171111
  7. Shakeri, Hassan et al. “Clinical effectiveness of kinesiological taping on pain and pain-free shoulder range of motion in patients with shoulder impingement syndrome: a randomized, double blinded, placebo-controlled trial.” International journal of sports physical therapy vol. 8,6 (2013): 800-10. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3867073/
  8. Chiu, Yuan-Chun et al. “The immediate effects of a shoulder brace on muscle activity and scapular kinematics in subjects with shoulder impingement syndrome and rounded shoulder posture: A randomized crossover design.” Gait & posture vol. 79 (2020): 162-169. DOI: 10.1016/j.gaitpost.2020.04.028