top of page
  • susanherdman

Frozen Shoulder - A Chilling Mystery!

What is it?

Frozen Shoulder (FS) is also known in the medical field as “Adhesive Capsulitis”, which, when broken down into English, means “Sticky Capsule”. This is close to, but not exactly accurate in, describing this very painful condition that results in a significant loss of your shoulder’s range of motion. FS drastically restricts the use of your arm – from reaching overhead for the cookies on the top shelf to even simply dressing yourself!

What’s going on?

There are a lot of tissues around the shoulder joint.

With FS – it’s not a muscle problem.

It’s not a joint problem either (like arthritis).

It has to do with the joint capsule itself.

The joint capsule not only surrounds the joint and holds in the synovial fluid (think lubricant!), but also helps contribute to the stability of the shoulder joint itself (1) allowing for the shoulders’ amazing hemispheric range of motion (ROM). There’s even a looser “pocket” on the underside of the capsule that acts like an accordion, unfolding as you reach your arm out to the side.

In FS, the capsule itself starts to get inflamed, thicken, and shrink onto the head of the upper arm bone. The folds of the “accordion” glue themselves together, which stops your arm from moving. Rather than “Adhesive” Capsulitis, perhaps “Shrunk” or “Contracted” Capsulitis may be more accurate (2).

What causes it?

Good question! Despite the term “Frozen Shoulder” first being coined by Codman in 1934 (3,4), researchers are still investigating the cause.

There are 2 general types of Frozen Shoulder (FS) (3):

  1. Primary FS – FS that comes out of nowhere, with an unknown cause

  2. Secondary FS – FS that can be related to a specific factor such as:

  • Systemic inflammation (eg. diabetes)

  • A condition that requires your arm to be in a sling for an extended period of time (eg. after shoulder surgery or fracturing your arm, stroke)

  • Rotator cuff or Biceps tendinopathy, Shoulder joint arthritis

Looking at a “frozen” joint capsule of the shoulder under the microscope, researchers have found evidence of multiple immune system & inflammatory processes going on (5). One specific process is described below:

In addition, nerves and blood vessels also start to grow into the joint capsule itself – making the joint exquisitely painful with even small movements (3).

Overall, FS appears to be more of a contracture or fibrosis of the shoulder joint resulting from multiple, complex biological processes. It does NOT appear to be a “wear-and-tear” kind of condition – as with rotator cuff injuries…

Instead, FS is highly associated with:

  • Metabolic syndrome (6) – which requires 3 of the following 5 conditions: Obesity, High blood pressure, Diabetes, High levels of triglycerides in the blood, Low levels of “good”/HDL cholesterol (7).

  • Chronic low levels of inflammation (6) – which is associated with factors that modern-day lifestyles bring including sedentary behaviours, smoking, alcohol, diet, chronic stress, fatigue, and anxiety (8; 9)

  • Hypothyroidism & Hyperthyroidism (3)

In fact, having Diabetes can put you at a 76% chance of getting FS sometime in your life! (5)

Other Risk Factors include:

  • Females are up to 4x more likely to have FS. However, if a male gets FS, unfortunately he’s more likely to have a longer recovery and poorer outcome. (5,10)

  • Middle age (Age 40-60) (5)

How do I know if I have FS?

  • Shoulder pain and stiffness came on spontaneously

  • Significantly restricted range of motion (eg. unable to reach overhead, into your back pocket, or put on a bra)

  • Pain when sleeping on that side

  • Sensitive/tender spot over the coracoid process (approx. 1 inch down and 1 inch in from the outermost part of your collarbone) (11)

How long does this condition last?

There are 3 general phases:

  • Freezing (where the shoulder is more painful than stiff – which results in disuse of that arm)

  • Frozen (where shoulder is primarily stiff)

  • Thawing (where shoulder stiffness slowly lessens)

Not ALL people go through all 3 stages nor do they progress at the same speed or achieve full range of motion by the end. Research has shown that FS will NOT resolve itself without treatment (12). For most people, symptoms last approximately 30months (10).

What can I do about it?

First, have your shoulder checked by a professional (eg. GP or physiotherapist) – to ensure there is nothing else causing your pain.

Second, use an effective pain relief method (eg. Heat, Ice, TENS (Transcutaneous Electrical Neuromuscular Stimulation ***NOT SAFE for those with pacemakers)) or get a corticosteroid injection from your doctor.

Third, with the help of your physiotherapist, find the right level of gentle exercises to help prevent your shoulder ROM from getting worse and eventually regain your ROM.

Fourth, reduce the chronic low-grade inflammation by addressing the modifiable risk factors mentioned above.

Working together with a physiotherapist can help make a plan that is right for you! Contact InReach Physio for more information.


By: Susan Herdman, Registered Physiotherapist – Specializing in Upper Extremity and Hand Telerehabilitation.

Book a telephysio / online physio / virtual physio appointment with a registered physiotherapist in British Columbia. InReach Online Physio services communities in northern and rural BC, such as Masset, Queen Charlotte, Fraser Lake, Fort Nelson, Fort St James, Dease Lake, Fort St John, Dawson Creek, the Gulf Islands, and more!


  1. Shaffer MA, Gaunt BW, Leggin BG, & Wolf BR (2021). Chapter 71: Rehabilitation of Shoulder Instability in Skirven, Osterman, Fedorczyk, Amadio, Feldscher, & Shin’s Rehabilitation of the Hand and Upper Extremity (7thEdition, pp. 991-1008). Philadelphia, PA: Elsevier.

  2. Ingraham, P. (2021). Complete guide to frozen shoulder: An extremely detailed science-based guide to one of the strangest of all common musculoskeletal problems, for both patietns and pros. Accessed Jun 14/2021:

  3. Piercey M, Kelley MJ, & Kuntz AF (2021). Chapter 70: Frozen Shoulder: Surgery and Therapy in Skirven, Osterman, Fedorczyk, Amadio, Feldscher, & Shin’s Rehabilitation of the Hand and Upper Extremity (7th Edition, pp. 977-990). Philadelphia, PA: Elsevier.

  4. Chepeha JC (2009). Chapter 4: Shoulder Trauma and Hypomobility in Magee, Zachazewski, & Quillen’s Pathology and Intervention in Musculoskeletal Rehabilitation (5th Edition, pp. 92-124). St. Louis, Missouri: Elsevier.

  5. de la Serna D, Navarro-Ledesma S, Alayón F, López E, & Pruimboom L (2021 May 11). A comprehensive view of frozen shoulder: A mystery syndrome. Frontiers in Medicine (Vol 8): Article 663703. Accessed Jun 14/’21:

  6. Pietrzak M (2016). Adhesive capsulitis: An age related symptom of metabolic syndrome and chronic low-grade inflammation? Med Hypotheses;88:12-7. doi: 10.1016/j.mehy.2016.01.002. PMID: 26880627. Accessed Jun 14/’21:

  7. The Johns Hopkins University (2021). Website: Health Home > Conditions and Diseases > Metabolic Syndrome. Accessed Jun 14/’21:

  8. Zimmerman M, AARP (2020 Jan 17). Website: Conditions & Treatments > Could Decreasing Inflammation Cure for Everything? Managing your body’s immune response is key to diseases of aging. Accessed Jun 14/’21:

  9. Bishop JY, Santiago-Torres JE, Rimmke N, & Flanigan DC (2015 Aug). Smoking predisposes to rotator cuff pathology and shoulder dysfunction: A systematic review. Arthroscopy;31(8):1598-605. doi: 10.1016/j.arthro.2015.01.026. Epub 2015 Mar 19. PMID: 25801046. Accessed Jun 14/’21:

  10. Page P & Labbe A (2010 Dec). Adhesive capsulitis: Use the evidence to integrate your interventions. NAJSPT;5(4):266-273. Accessed Jun 14/’21:

  11. Carbone S, Gumina S, Vestri AR, & Postacchini R (2010 Mar). Coracoid pain test: a new clinical sign of shoulder adhesive capsulitis. Int Orthop; 34(3):385-8. doi: 10.1007/s00264-009-0791-4. PMID: 19418052. Accessed Jun 14/’21:

  12. Wong CK, Levine WN, Deo K, Kesting RS, Mercer EA, Schram GA, & Strang BL (2017 Mar). Natural history of frozen shoulder: fact or fiction? A systematic review. Physiotherapy;103(1):40-47. doi: 10.1016/ Epub 2016 Jun 21. PMID: 27641499. Accessed Jun 14/’21:

68 views0 comments


bottom of page