Understanding Frozen Shoulder: Pathophysiology, Incidence, and Evidence-Based Treatments
Frozen shoulder, or adhesive capsulitis, is a painful condition that affects the shoulder joint, leading to stiffness, pain, and a restricted range of motion. This condition can interfere with daily activities, making it a significant concern for many individuals. In this blog, we will explore what frozen shoulder is, its underlying pathophysiology, its prevalence, and the most effective, evidence-based treatments to manage the condition.
What is Frozen Shoulder?
Frozen shoulder is a condition that causes stiffness and pain in the shoulder joint, typically restricting movement in all directions. The shoulder joint is a ball-and-socket joint, and the capsule around the joint thickens and tightens, causing inflammation. This tightening and thickening result in limited range of motion and significant discomfort. The exact cause of frozen shoulder is not always clear, but it often develops gradually and can be triggered by injury or overuse.
There are three stages of frozen shoulder:
Freezing Stage: Characterized by pain and gradual loss of range of motion.
Frozen Stage: Pain may decrease, but the shoulder remains stiff with significantly limited movement.
Thawing Stage: The shoulder begins to regain motion and flexibility, but this process can take months to years.
Pathophysiology of Frozen Shoulder
The pathophysiology of frozen shoulder involves an inflammatory response in the synovial capsule of the shoulder. The joint capsule becomes thickened and contracted, leading to the restriction of movement. This process is believed to be driven by an immune response that causes fibrosis and thickening of the capsule, eventually leading to adhesions (scar tissue) that restrict normal motion.
During the "freezing" stage, inflammation occurs in the shoulder's capsule, resulting in pain and loss of movement. As the condition progresses to the "frozen" stage, inflammation diminishes but the stiffness persists due to fibrosis and scarring of the capsule. The “thawing” stage involves gradual tissue remodeling and return of shoulder movement as the fibrosis resolves.
While the exact cause is not always known, frozen shoulder is often associated with:
Injury or surgery: Shoulder trauma or procedures like rotator cuff surgery can increase the risk.
Chronic conditions: Diabetes, thyroid disorders, and heart disease are frequently linked to frozen shoulder. Individuals with diabetes are at higher risk, with some studies showing a prevalence of frozen shoulder of up to 20% in this population.
Age and gender: The condition is most common in individuals between the ages of 40 and 60, with women being more likely to develop frozen shoulder than men.
Incidence and Prevalence
Frozen shoulder affects approximately 2-5% of the general population, with certain groups being more susceptible. As mentioned, it is most common in individuals between 40-60 years old and more prevalent in women. The incidence in people with diabetes is significantly higher, ranging from 10-20%. Studies suggest that frozen shoulder often develops following immobilization or after a shoulder injury, such as a rotator cuff tear or surgery.
The condition is typically self-limiting, meaning it often resolves on its own over time, though it can take a long time to recover—sometimes up to 3 years. Despite its natural course, the symptoms can severely impair quality of life, making effective treatment crucial.
Evidence-Based Treatments for Frozen Shoulder
Treatment for frozen shoulder typically includes a combination of physical therapy, medications, and, in some cases, surgical interventions. Evidence-based approaches for managing the condition focus on reducing pain, increasing range of motion, and improving overall shoulder function. Here are the most effective treatment options:
Physical Therapy
Stretching and Strengthening Exercises: Physical therapy is the cornerstone of treatment for frozen shoulder. Stretching exercises to improve shoulder mobility and strengthening exercises to maintain muscle function are critical in all stages of the condition. Research published in the Journal of Orthopaedic & Sports Physical Therapy shows that specific stretches and mobilizations significantly improve shoulder function in patients with frozen shoulder.
Manual Therapy: Physical therapists may use techniques such as joint mobilization and soft tissue manipulation to reduce stiffness and improve the range of motion. A study in Physical Therapy in Sport demonstrated that manual therapy, in combination with exercise, provides better outcomes in improving movement and reducing pain.
Modalities: Heat, ice, or dry needling therapy may be used to reduce inflammation and pain during the initial stages of the condition, aiding in movement and stretching exercises.
Corticosteroid Injections
In cases where pain is severe and limits participation in physical therapy, corticosteroid injections may be recommended. These injections help to reduce inflammation and pain, allowing for better engagement in rehabilitation exercises. Research supports the use of corticosteroid injections for short-term pain relief, particularly during the "freezing" and "frozen" stages.
Stretching and Mobilization Techniques
Frozen Shoulder Manipulation: In severe cases, a procedure called "manipulation under anesthesia" may be considered. In this procedure, the shoulder is carefully moved through its full range of motion while the patient is under anesthesia. This can help break up scar tissue and improve mobility.
Arthroscopic Release: If non-invasive treatments fail, arthroscopic surgery may be recommended to remove scar tissue or release the contracted capsule. Studies suggest that this procedure can significantly improve the range of motion and provide long-term relief.
Surgical Treatment
Surgery is typically a last resort after conservative treatments fail to provide relief. As previously mentioned, arthroscopic capsular release may be performed to remove the tight and fibrotic tissue from the shoulder joint, which is effective in restoring motion. This option is usually reserved for patients who have not responded to physical therapy and corticosteroid injections.
Self-care and Lifestyle Adjustments
Rest and Ice: During the acute pain phase, rest and applying ice can help reduce swelling and discomfort. It is important to balance rest with movement to prevent further stiffness.
Ergonomics: Using proper posture and ergonomics during daily activities can help minimize strain on the shoulder and prevent aggravating symptoms. A physical therapist can provide advice on modifying movements to reduce pain and stress on the shoulder.
Conclusion
Frozen shoulder can be a frustrating and downright debilitating condition, but with the right treatment plan, it is highly manageable. Early intervention through physical therapy, pain management strategies, and, when necessary, surgical options can greatly improve outcomes. If you’re dealing with frozen shoulder or suspect you may have it, consider consulting with a physical therapist for a comprehensive evaluation and personalized treatment plan. At Wildflower Physical Therapy & Wellness, we are here to help you regain mobility and alleviate pain, so you can return to your daily activities with ease. Contact us today to learn more about how we can assist you on your road to recovery.
If you are struggling with illness or injury and would like to get your body moving, schedule a physical therapy appointment with us today! At Wildflower Physical Therapy & Wellness, we can help you to get back to the life you want to live through pain management strategies, activity promotion and exercise. Our Cash Based Physical Therapy model allows us to deliver a highly individualized treatment plan without the fuss of insurance companies. Interested in trying dry needling to support your exercise routine and maximize recovery? Reach out to us today!