Frozen shoulder medically termed 'adhesive capsulitis (AC)' has an incidence of between 3 to 5% worldwide and characterised by the development of dense adhesions and thickening of the joint capsule (2, 3). The condition leads to progressive pain, stiffness and limited active and passive ranges of motion within the shoulder joint. Symptoms are often worse at night and radiological scanning appears normal (3).
The typical patient that develops adhesive capsulitis are women aged between 50 to 70 and has been reported to occur within both shoulders simultaneously in up to 40-50% of patients. Adhesive capsulitis is commonly associated with other systemic and nonsystemic conditions. By far the most common is the co-morbid condition of diabetes mellitus, with an incidence of 10–36%.
Codman (1934) was the first to describe AC and the common criteria shared by individuals with frozen shoulder which include the slow onset of pain, inability to sleep on the affected side, painful and restricted shoulder abduction and external rotation motions. Plain x-rays of shoulders with AC may range from a normal appearance to osteopenic or degenerative changes (2).
Other co-morbid conditions include hyperthyroidism, hypothyroidism, hypoadrenalism, Parkinson’s disease, cardiac disease, pulmonary disease, stroke, and even surgical procedures that do not affect the shoulder such as cardiac surgery, cardiac catheterization, neurosurgery, and radical neck dissection.
Although some have described adhesive capsulitis as a self-limiting disorder that resolves in 1–4 years, other studies report that 20 - 50% of patients with adhesive capsulitis which suffer long-term range of movement deficits may last up to 10 years. Up to 15% of FS patients will suffer from a long-term disability
Clinical Phases (6):
The condition progresses in three stages:
1. Freezing;
pain is most severe during this phase. This inflammatory phase typically lasts between 3 and 9 months. The stage is characterised by an acute synovitis of the glenohumeral joint, when the synovium or of the connective tissue that lines the inside of the joint capsule becomes inflamed.
2. Frozen
or adhesive, stiff phase whereby the pain
gradually reduces but the range of motion in all planes becomes severely restricted. This stage lasts anywhere 4 to 12 months.
3. Thawing or recovery phase involves the gradual spontaneous improvement of
shoulder function (5-26 months).
It is generally believed that frozen shoulder develops as a result of perivascular inflammation and fibroblastic proliferation, followed by capsular fibrosis and contracture.
Frozen shoulder syndrome has been classified into “primary” and “secondary”.
Primary
adhesive capsulitis is idiopathic with the cause being unknown and classified to patients who present with no significant findings within their case history, clinical examination, or radiographic evaluation to explain their loss of joint motion and pain (1).
Primary idiopathic frozen shoulder can be associated with other diseases and conditions such as diabetes mellitus and might be the first presentation of a diabetic patient. Patients with systemic diseases such as thyroid, cardiovascular and lung diseases along with open heart surgery, depression, polymyalgia and Parkinson’s disease are also at higher risk.
Patients with
secondary
adhesive capsulitis disclose a trauma or surgery to the affected upper extremity prior to their shoulder symptomatology (1).
Adhesive capsulitis usually manifests itself in 12-42 months, but it may be as early as 6 months or as late as 10 years (1).
The pancreas is a large gland located behind the stomach and has the function of maintaining healthy blood sugar levels by producing insulin, glucagon and other hormones (5).
Diabetes is a metabolic condition characterised
by hyperglycemia caused by insulin deficiency and / or impaired effectiveness of insulin action. The disease is considered one of the most challenging and disabling health problems
in the 21st century with being the fifth leading cause of death in most developed
countries (1).
The disease can be classified into two main types. Type 1 diabetes (T1D) is an organ-specific autoimmune disease caused by an autoimmune response against pancreatic islet beta cells which results to the loss of insulin production (1). Type 2 diabetes occurs from insulin deficiency and/ or insulin resistance (1). Diabetic patients are five time more likely than nondiabetic patients to develop frozen shoulder (1).
Classic Warning Signs and Symptoms for Diabetes
Polyuria (increased urination), polydypsia (increased thirst) and polyphagia (increased hunger) which occurs commonly in type 1 and 2 diabetes with very high levels of hyperglycaemia are usually clear signs and symptoms. Severe weight loss is common only in type 1 diabetes or if type 2 diabetes remains undetected for a long period. Unexplained weight loss, fatigue, irritability and restlessness and body pain are also common signs of undetected diabetes. The condition can be difficult to catch as symptoms can be mild or have a gradual development and remain unnoticed.
Other signs and symptoms include (3):
- Repeated infections especially in the genital areas, urinary tract, skin, oral cavity and delayed wound healing.
- Dry mouth
- Burning, pain, numbness on the feet along with Itching.
- Reactive hypoglycaemia
- Acanthoses nigricans or the presence of velvety dark patches of the neck, arm pit, groin which is an indication of insulin resistance.
- Reduced vision
- Impotence or erectile dysfunction
Advanced Glycation End Products (AGEs)
Advanced Glycation End Products or AGES are proteins or lipids that become glycated by having an added sugar molecule after having undergone glycation. Glycation end products are believed to play a causative role in the vascular complications of diabetes mellitus. In diabetic tissue, hyperglycemia can cause a non-enzymatic covalent bonding of sugar molecules to collagen fibers. Over time, AGEs increase the cross linking of collagen fibres of the shoulder capsule, thus changing the mechanical properties of tissue by making the structures stiffer and weaker (1).
Particularly for clients with a primary AC, it is advisable to have a blood test to understand whether there might be an associated undiagnosed underlying cause listed above. Available management strategies may include the use of analgesia, such as non‐steroidal anti‐inflammatory drugs (NSAIDs) and/or intra‐articular steroid injection. Encouragement of activity by performing specific exercises is crucial to improve joint range of motion. In rare cases, surgical procedures can be considered, such as manipulation under anesthesia or capsular release under arthroscopic guidance.
As Ben-Arie et al.,
(2020) highlight, there is still disagreement upon which treatment is the most effective for reducing pain and restoring ROM for patients with FS but most research has found strong evidence in favor of laser therapy and steroid injections for pain treatment in the short term (4).
Massage
Massage modalities can be applied with the aim to increase blood circulation, relieve pain by interfering with pain signals' pathway to the brain via the 'gate control theory', stimulate the release of endorphins, encourage lymphatic drainage, relieve muscle tension and spasms.
Dry Cupping Two case studies investigated the effectiveness of dry cupping (hijamah) whilst individuals were in phase two of having adhesive capsulitis. Suctioning of cups with gliding techniques were applied at the affected areas (1, 8).
The treatment modality aims to encourage blood flow to the area and increase the permeability of blood vessels which helps aid exudation of plasma proteins and fluid into the tissue to create swelling or oedema (1). The vacuum technique also aims to help the circulation of lymphatic fluid, reduce inflammation and facilitate recruitment of immune cells and support the healing process (1). Both case studies found significant improvements with reduced pain levels, active range of joint movement and muscular tenderness.
Acupuncture
A systematic review and a meta-analysis by Ben-Arie et al.,
(2020) concluded that acupuncture had shown to be a safe treatment with a significant effect in regard to reducing pain, improving shoulder function, and flexion ROM in the short term and midterm after analysing a total of 966 FS patients from 13 publications (4).