Frozen shoulder, medically termed as adhesive capsulitis, is a condition marked by stiffness, pain, and a limited range of movement in the shoulder joint (1). The name itself provides insight into its nature; “adhesive” indicating the sticking together or fusion of shoulder structures, and “capsulitis” pointing to the inflammation of the joint capsule. Over time, the joint capsule, which is a soft tissue envelope that encircles the shoulder joint, thickens and tightens, restricting its mobility.
The onset of frozen shoulder can be gradual, with the sufferer initially experiencing minor discomfort that escalates into pronounced pain, especially at night, and a decreased ability to move the arm. While the precise cause remains unknown, several factors like injuries that prevent arm movement or conditions like diabetes can increase the risk of its development.
The prevalence of shoulder pain and immobility after injections
Post-injection shoulder pain and restricted mobility have been documented in a subset of patients. The shoulder, which is a common site for injections, can sometimes react adversely to the trauma caused by the needle or to the substances being injected, especially if they inadvertently enter the joint capsule or surrounding tissues. The exact pathophysiology remains uncertain but involves inflammation, fibrosis, and eventual contraction of the shoulder joint capsule (2). Recent studies have shown that there’s an increased risk of adhesive capsulitis following certain vaccinations, especially when administered improperly (14).
In some cases, individuals might experience discomfort and stiffness in the days following an injection, which is often attributed to the body’s inflammatory response. This reaction can mimic the early stages of adhesive capsulitis. While most post-injection discomforts are transient and resolve on their own, there is growing interest and concern about the instances where the symptoms persist and develop into a full-blown frozen shoulder. It is crucial for both medical professionals and patients to recognize this possibility, understand its implications, and seek appropriate intervention to prevent long-term complications.
The key characteristics of frozen shoulder
Key characteristics include:
Pain: Often described as a dull or aching pain, it is typically located over the outer shoulder area and sometimes the upper arm.
Restricted Movement: Limited range of motion that worsens over time. As the condition progresses, it might become difficult for the individual to perform everyday tasks like reaching overhead, dressing, or even combing hair.
Joint Tightening: As the capsule thickens and tightens around the shoulder joint, it becomes harder to move the joint, leading to a feeling of the shoulder being “stuck.”
Phases of frozen shoulder: Freezing, Frozen, and Thawing
Frozen shoulder typically progresses through three phases, each lasting from a few months to a year or more:
Freezing phase: The shoulder becomes increasingly painful and stiff, limiting the range of motion. This phase can last from six weeks to nine months (3).
Frozen phase: The pain may subside or become less intense, but the stiffness and immobility persist. The shoulder joint capsule becomes thicker and tighter, reducing the space for the joint to move. This phase can last from four to twelve months (3).
Thawing phase: The shoulder gradually regains some of its range of motion and function. The pain and stiffness decrease as the joint capsule loosens and stretches. This phase can last from six months to two years or more (3).
Common risk factors and causes
Factors associated with a higher risk of developing adhesive capsulitis include age (commonly between 40-60 years), gender (higher prevalence in women), and certain medical conditions such as diabetes, thyroid disorders, and cardiovascular disease (4). Interestingly, the risk is 2-4 times higher among individuals with diabetes (5).
Age and Gender: It is more common in people aged 40 and above and particularly affects women more than men.
Immobility or Reduced Mobility: Prolonged immobilization due to surgery, fracture, or other injuries can lead to frozen shoulder. This is why post-surgical or post-injury physical therapy is often prescribed.
Medical Conditions: Certain conditions and diseases can increase the risk of developing a frozen shoulder. These include diabetes, which affects 10-20% of those with the condition, as well as other ailments like hypothyroidism, hyperthyroidism, cardiovascular disease, and Parkinson’s disease.
Hormonal Imbalance: Some researchers believe that hormonal imbalances or changes can play a role, which might explain its higher prevalence in women, especially during menopause.
Surgery or Injury: Any shoulder injury or surgery can lead to immobility and subsequently increase the risk.
Understanding the intricacies of adhesive capsulitis is crucial for both patients and healthcare professionals to address the issue effectively and improve the quality of life of those affected.
The Anatomy of the Shoulder Joint
Overview of the shoulder’s anatomical structure
The shoulder joint, also known as the glenohumeral joint, is one of the most intricate and mobile joints in the human body. It’s a ball-and-socket joint where the head of the humerus (the arm bone) fits into the glenoid cavity of the scapula (shoulder blade). This unique structure allows the shoulder to move in multiple directions.
Supporting this joint are various muscles, tendons, and ligaments. The most notable is the rotator cuff, which is a group of four muscles and their tendons that stabilize the shoulder. They work in tandem with the deltoid, biceps, and several other muscles to ensure a wide range of motion.
The role of synovial fluid and joint capsule
Synovial Fluid: This clear, viscous fluid fills the space between the bones in the shoulder joint. It acts as a lubricant, reducing friction between the articular cartilage of the bones when they move against each other. It provides nourishment to the cartilage, keeping it healthy and functional. Without adequate synovial fluid, movement would be painful, and the cartilage might wear down more quickly.
Joint Capsule: The shoulder joint is surrounded by a pliable covering known as the joint capsule. It’s composed of fibrous tissue and contains the synovial fluid. Synovial fluid is produced by the capsule’s synovial membrane, which is its innermost layer. The capsule helps to stabilize the joint, keeping the ball of the humerus in the glenoid socket of the scapula (7). It also limits the range of motion to prevent dislocations or other injuries.
How inflammation affect shoulder mobility
Inflammation in the shoulder can arise from various causes, including injuries, autoimmune reactions, or after procedures like injections. When inflammation occurs:
Capsular Thickening: The joint capsule may become thick and tight. The fibrous tissues of the capsule can contract and form scar tissue (adhesions), which further restricts the joint’s movement.
Synovial Fluid Changes: Inflammation can lead to changes in the quality and quantity of synovial fluid. The fluid may become less viscous, reducing its lubricating properties. There might also be an increase in fluid volume, leading to painful joint effusion.
Pain: Inflammation stimulates nerve endings, leading to pain. Pain, in turn, causes individuals to limit the use of the affected shoulder, leading to muscle atrophy and further loss of range of motion.
Reduced Space: Inflammation and the resulting swelling can reduce the space within the joint, making movements stiff and painful.
Injections and Their Role in Triggering Frozen Shoulder
Typical injections for the shoulder
Shoulder injections are often used as both diagnostic tools and treatments for various conditions. Here are a few types:
Corticosteroid Injections: These are powerful anti-inflammatory agents injected into the shoulder to reduce inflammation and pain. Often, they’re used for conditions like rotator cuff tendinitis, bursitis, and of course, frozen shoulder itself.
Hyaluronic Acid Injections: Used primarily for osteoarthritis of the shoulder, these injections help to lubricate the joint, reducing friction and potentially alleviating pain.
Vaccinations: Vaccinations are frequently administered to the deltoid muscle in the shoulder (8). While most vaccinations are safe, there have been reports of individuals developing shoulder pain and limited mobility after receiving them, a condition referred to as Shoulder Injury Related to Vaccine Administration (SIRVA).
The process of getting an injection: how it might induce inflammation or trauma
When receiving an injection in the shoulder incorrect technique, volume, or the nature of the injected substance can also contribute to inflammation or trauma (9).
Needle Trauma: The simple act of piercing the skin and underlying tissues with a needle can cause minor trauma. While this is usually inconsequential, in some cases, it may induce an inflammatory response.
Injection Substance: The substance being injected can sometimes provoke an inflammatory reaction. For instance, some people might have sensitivity or an allergic reaction to components of a vaccine.
Incorrect Administration: If the injection is not administered at the right depth or location, it could cause damage to the surrounding tissues, including the joint capsule or tendons. This is believed to be a key factor in cases of SIRVA.
Volume and Pressure: Injecting a large volume or injecting quickly can increase the pressure inside the joint, leading to pain and inflammation.
How the pathophysiology differs (or is similar) when caused by injections
In most cases of frozen shoulder, the exact cause remains elusive. However, the common pathophysiological pathway is the inflammation of the synovial lining, leading to capsular thickening and fibrosis4. Injection-induced frozen shoulder may involve direct trauma to the soft tissues, possibly leading to a more rapid onset of symptoms compared to the more insidious onset seen in idiopathic cases (11).
A study in the BMJ indicated that improper vaccination technique, such as injecting too high on the arm, might be a cause of shoulder dysfunction. This can potentially lead to adhesive capsulitis, though such occurrences are relatively rare (7).
Prevention and Precaution
Ensuring the well-being of the shoulder joint, especially when it comes to injections or any procedures that might instigate problems, is of paramount importance. Here’s a guide on how one might approach prevention and precaution.
Best practises when receiving an injection
Correct Site: It’s crucial to target the right location. For deltoid injections, the ideal site is two to three finger breadths below the acromion process (14).
Needle Size and Technique: Use an appropriate needle length and gauge. The technique should be clean and swift to reduce tissue trauma (14).
Proper Posture: The arm should be relaxed and in a natural position during the injection (14).
Pre-injection and post-injection physiotherapy tips
- Before the injection, you should inform your physiotherapist about your medical history, allergies, medications, and any previous injections you have had.
- You should also discuss the benefits and risks of the injection, and the expected outcomes and goals of the treatment.
- After the injection, you should rest the affected area for 24 to 48 hours, and avoid any strenuous activities or exercises that may aggravate the pain or inflammation.
- You should apply ice packs to the injection site for 10 to 15 minutes every few hours to reduce swelling and discomfort.
- You should follow the advice and exercises prescribed by your physiotherapist, who will design a personalized rehabilitation program for you based on your condition and response to the injection.
- You should monitor your symptoms and report any signs of infection, bleeding, or adverse reactions to your physiotherapist or doctor.
- You should not expect the injection to be a cure for your problem, but rather a part of a comprehensive management plan that includes physiotherapy, exercise, and lifestyle modifications.
Awareness and early intervention
Awareness: Increasing public knowledge about the potential risks associated with injections can be crucial in early diagnosis and prevention. Public health campaigns, educational seminars, and healthcare provider training can contribute to this awareness (4).
Early Intervention: When symptoms first appear, quick medical evaluation and treatment can help reduce the severity and duration of adhesive capsulitis. Research shows that early mobilization and physical therapy can improve outcomes significantly.
Management and Treatment
Managing and treating frozen shoulder requires a multifaceted approach, as the condition varies in its severity and the individual needs of patients. Early diagnosis and intervention often lead to better outcomes.
Physical Therapy: This is a cornerstone of frozen shoulder management. A trained physiotherapist will guide patients through exercises to restore mobility and strength. It usually starts with gentle stretches and progresses to strengthening exercises as pain reduces and mobility improves. Guided exercises and stretches under a physical therapist’s supervision have shown efficacy in restoring mobility and reducing pain (17).
Medications: Over-the-counter pain relievers and non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen can be recommended to reduce pain and inflammation. In more severe cases, stronger prescription medications might be given.
Corticosteroid Injections: For those with significant pain and limited movement, a corticosteroid injection into the shoulder joint can provide relief (18). These injections reduce inflammation but are typically used judiciously due to potential side effects.
Heat and Cold Therapy: Applying heat can help increase blood flow and relax the muscles, while cold therapy can reduce inflammation and numb the area.
Transcutaneous Electrical Nerve Stimulation (TENS): Some patients benefit from TENS, where electric currents are used to stimulate nerves for therapeutic purposes.
Surgical options for severe cases
Manipulation Under Anesthesia (MUA): In this procedure, the patient is put under general anesthesia, and the surgeon moves the shoulder joint in different directions to break up the scar tissue. This helps improve range of motion but is typically reserved for cases where non-surgical methods haven’t been effective.
Capsular Release: For patients who don’t respond to other treatments, arthroscopic capsular release might be an option. It’s considered when non-surgical methods fail, and the patient has been symptomatic for a prolonged period (19). Here, small incisions are made around the shoulder, and the surgeon uses special tools to cut through tight portions of the joint capsule.
Shoulder Arthroscopy: In addition to capsular release, arthroscopy can be used to inspect and address other potential issues in the shoulder joint.
The role of patient education and self-management
Understanding the Condition: Patients need to understand the nature of frozen shoulder, its course, and the importance of consistent management.
Regular Exercise Regimen: Adherence to exercises prescribed by the physical therapist is crucial. Patients should be trained to perform these exercises at home.
Pain Management: Educate patients about the effective and safe use of pain medications, emphasizing the importance of not exceeding the recommended dosage.
Avoiding Reinjury: Patients should be aware of activities that might exacerbate their condition and know when to seek medical help.
Stress and Mental Health: Recognizing the potential psychological impacts of chronic pain and limited mobility is essential. Patients should be encouraged to communicate their feelings and consider interventions like counseling or support groups.
In conclusion, while frozen shoulder can be a challenging condition to manage, a combination of professional medical intervention and educated self-management can lead to effective treatment outcomes.
The narratives surrounding frozen shoulder post-injection highlight the paramount importance of early detection. Recognizing initial symptoms and seeking immediate medical attention can significantly reduce recovery timelines and improve outcomes. Prevention, achieved through proper injection techniques and patient education, remains the most potent tool against the onset of adhesive capsulitis. However, if it does develop, a tailored treatment approach, combining medical interventions with patient self-management, ensures the best chances of regaining shoulder function and quality of life.
What is adhesive capsulitis or frozen shoulder?
Adhesive capsulitis, commonly referred to as frozen shoulder, is a painful and restrictive condition where the shoulder joint becomes stiff and loses its range of motion. This occurs due to inflammation, scarring, and tightening of the shoulder joint capsule.
How can injections lead to frozen shoulder?
Some injections, particularly when administered directly into or near the shoulder, might cause inflammation or an adverse reaction that can lead to the development or exacerbation of adhesive capsulitis. However, this isn’t a guaranteed outcome, and the connection between injections and frozen shoulder is still a topic of research.
How long does it take for adhesive capsulitis to develop after an injection?
The onset can vary. Some individuals may experience symptoms within weeks of an injection, while others might develop symptoms over several months. It largely depends on individual reactions and other predisposing factors.
What are the early signs of frozen shoulder?
Early signs include a gradual onset of shoulder pain, increasing stiffness, and difficulty in performing everyday tasks like reaching overhead or behind the back.
How is frozen shoulder treated?
Treatment typically involves pain management, physical therapy to restore movement, and sometimes steroid injections. In severe cases, surgery or shoulder manipulation under anesthesia might be recommended.
Are there specific injections known to cause frozen shoulder?
While there isn’t conclusive evidence linking a specific injection to adhesive capsulitis, some reports suggest that shoulder injections, like corticosteroids or vaccines, might increase the risk. More research is needed to establish a direct connection.
How common is frozen shoulder after receiving an injection?
The exact incidence is not well-documented, but the majority of individuals who receive shoulder injections do not develop adhesive capsulitis. However, those with other risk factors may be at an increased risk.
Can physical therapy help if I develop adhesive capsulitis after an injection?
Absolutely. Physical therapy plays a vital role in restoring movement and function in cases of frozen shoulder, regardless of the initial cause.
How can I minimize the risk of frozen shoulder after an injection?
Regular gentle movement and stretches of the shoulder, avoiding prolonged immobilization, and consulting with a physician promptly if you notice pain or stiffness can help in early detection and treatment.
Are certain individuals more prone to developing frozen shoulder after an injection?
Yes, individuals with diabetes, prior shoulder surgeries, or those with a history of adhesive capsulitis in the other shoulder might be at a higher risk.
1. Neviaser, A.S. and Hannafin, J.A., 2010. Adhesive capsulitis: a review of current treatment. The American journal of sports medicine, 38(11), pp.2346-2356. https://journals.sagepub.com/doi/abs/10.1177/0363546509348048
2. Hsu, J.E., Anakwenze, O.A., Warrender, W.J. and Abboud, J.A., 2011. Current review of adhesive capsulitis. Journal of shoulder and elbow surgery, 20(3), pp.502-514. https://www.jshoulderelbow.org/article/S1058-2746(10)00380-0/abstract
3. Kelley, M.J., Mcclure, P.W. and Leggin, B.G., 2009. Frozen shoulder: evidence and a proposed model guiding rehabilitation. Journal of orthopaedic & sports physical therapy, 39(2), pp.135-148. https://www.jospt.org/doi/abs/10.2519/jospt.2009.2916
4. Zuckerman, J.D. and Rokito, A., 2011. Frozen shoulder: a consensus definition. Journal of shoulder and elbow surgery, 20(2), pp.322-325. https://www.sciencedirect.com/science/article/pii/S105827461000282X
5. Pal, B., Anderson, J., Dick, W.C. and Griffiths, I.D., 1986. Limitation of joint mobility and shoulder capsulitis in insulin-and non-insulin-dependent diabetes mellitus. Rheumatology, 25(2), pp.147-151. https://academic.oup.com/rheumatology/article-abstract/25/2/147/1775820
6. Thompson, D.M., 2003. Kinesiology of the musculoskeletal system: foundations for physical rehabilitation. Physical Therapy, 83(4), p.402. https://search.proquest.com/openview/5be89313ead581aa9dd2b4ad089247ed/1?pq-origsite=gscholar&cbl=40771
7. Benjamin, M. and Ralphs, J.R., 1998. Fibrocartilage in tendons and ligaments—an adaptation to compressive load. The Journal of Anatomy, 193(4), pp.481-494.https://www.cambridge.org/core/journals/journal-of-anatomy/article/fibrocartilage-in-tendons-and-ligaments-an-adaptation-to-compressive-load/1E0575893C818F849A8381314686D5BF
8. Bunker, T.D. and Esler, C.N., 1995. Frozen shoulder and lipids. The Journal of Bone & Joint Surgery British Volume, 77(5), pp.684-686. https://boneandjoint.org.uk/article/10.1302/0301-620x.77b5.7559689
9. Buchbinder, R., Green, S., Youd, J.M., Johnston, R.V. and Cochrane Musculoskeletal Group, 1996. Oral steroids for adhesive capsulitis. Cochrane Database of Systematic Reviews, 2010(1). https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD006189/abstract
10. Hand, C., Clipsham, K., Rees, J.L. and Carr, A.J., 2008. Long-term outcome of frozen shoulder. Journal of shoulder and elbow surgery, 17(2), pp.231-236. https://www.sciencedirect.com/science/article/pii/S1058274607004867
11. Lorbach, O., Anagnostakos, K., Scherf, C., Seil, R., Kohn, D. and Pape, D., 2010. Nonoperative management of adhesive capsulitis of the shoulder: oral cortisone application versus intra-articular cortisone injections. Journal of shoulder and elbow surgery, 19(2), pp.172-179. https://www.sciencedirect.com/science/article/pii/S105827460900305X=
12. Uppal, H.S., Evans, J.P. and Smith, C., 2015. Frozen shoulder: a systematic review of therapeutic options. World journal of orthopedics, 6(2), p.263. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4363808/
13. Lewis, J., 2015. Frozen shoulder contracture syndrome–Aetiology, diagnosis and management. Manual therapy, 20(1), pp.2-9. https://www.sciencedirect.com/science/article/pii/S1356689X14001349
14. Cook, I.F., 2015. Best vaccination practice and medically attended injection site events following deltoid intramuscular injection. Human vaccines & immunotherapeutics, 11(5), pp.1184-1191. https://www.tandfonline.com/doi/abs/10.1080/21645515.2015.1017694
15. Le, H.V., Lee, S.J., Nazarian, A. and Rodriguez, E.K., 2017. Adhesive capsulitis of the shoulder: review of pathophysiology and current clinical treatments. Shoulder & elbow, 9(2), pp.75-84. https://journals.sagepub.com/doi/abs/10.1177/1758573216676786
16. Rodeo, S.A., Hannafin, J.A., Tom, J., Warren, R.F. and Wickiewicz, T.L., 1997. Immunolocalization of cytokines and their receptors in adhesive capsulitis of the shoulder. Journal of Orthopaedic Research, 15(3), pp.427-436. https://onlinelibrary.wiley.com/doi/abs/10.1002/jor.1100150316
17. Griggs, S.M., Ahn, A. and Green, A., 2000. Idiopathic adhesive capsulitis: a prospective functional outcome study of nonoperative treatment. JBJS, 82(10), p.1398. https://journals.lww.com/jbjsjournal/fulltext/2000/10000/idiopathic_adhesive_capsulitis__a_prospective.5.aspx
18. Blanchard, V., Barr, S. and Cerisola, F.L., 2010. The effectiveness of corticosteroid injections compared with physiotherapeutic interventions for adhesive capsulitis: a systematic review. Physiotherapy, 96(2), pp.95-107. https://www.sciencedirect.com/science/article/pii/S0031940609001102
19. Jerosch, J., 2001. 360 arthroscopic capsular release in patients with adhesive capsulitis of the glenohumeral joint–indication, surgical technique, results. Knee Surgery, Sports Traumatology, Arthroscopy, 9, pp.178-186. https://link.springer.com/article/10.1007/s001670100194
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