Frozen shoulder- medically known as adhesive capsulitis- is a condition characterized by progressive shoulder stiffness, pain, and marked restriction of movement. It can develop gradually without obvious injury and affects approximately 2–5% of the general population, with higher rates in people with diabetes, thyroid disorders, or a history of shoulder immobilization.
For many patients, a frozen shoulder is a long, difficult condition to live with. Recovery without intervention can take one to three years, and not all patients regain full function. This regenerative approach represents an emerging regenerative approach that targets the underlying inflammatory and fibrotic processes driving the condition.
Understanding Frozen Shoulder: The Three Stages
What is frozen shoulder at its core? Adhesive capsulitis involves the progressive thickening and contraction of the shoulder joint capsule- the fibrous tissue that encloses the shoulder joint. This process occurs in three recognized stages:
Stage 1- Freezing (painful): Gradual onset of shoulder pain, often worse at night, with early stiffness developing over 2–9 months.
Stage 2- Frozen (stiff): Pain may begin to ease, but stiffness reaches its maximum. Range of motion- especially external rotation and overhead movement- is severely restricted. This stage lasts 4–12 months.
Stage 3- Thawing (recovering): Gradual return of shoulder motion, typically over 6–24 months. Not all patients recover full range of motion.
The capsular thickening and fibrosis are driven by chronic inflammation, with myofibroblasts (inflammatory fibroblasts) depositing excess collagen in the joint capsule (Neviaser & Hannafin, Am J Sports Med., 2010).
Conventional Frozen Shoulder Treatments and Their Limitations
Standard frozen shoulder treatments are primarily aimed at reducing pain and preserving or recovering range of motion:
- Physical therapy with stretching and manual mobilization
- Corticosteroid injections to reduce acute inflammation
- Hydrodilatation– injecting fluid into the joint capsule to expand and stretch it
- Oral anti-inflammatory medications
- Manipulation under anesthesia for severe cases with inadequate improvement
- Arthroscopic capsular release as a surgical option
These approaches can be helpful, particularly in the earlier stages. However, many patients experience slow, incomplete recovery- especially when the condition has progressed to severe fibrosis or when underlying conditions like diabetes complicate the healing process.
How Stem Cell Therapy May Help Frozen Shoulder
The biological basis for using stem cell therapy in frozen shoulders lies in the properties of mesenchymal stem cells (MSCs) to modulate the immune environment and influence fibrotic processes.
MSCs release anti-inflammatory cytokines that can downregulate the chronic low-grade inflammation driving capsular thickening. They also produce anti-fibrotic factors- including hepatocyte growth factor (HGF) and PGE2- that may reduce the excess collagen deposition that causes the capsular contracture characteristic of frozen shoulder.
In addition, MSCs support tissue remodeling by influencing the balance between matrix metalloproteinases (enzymes that break down collagen) and their inhibitors. This could potentially help soften and remodel the thickened shoulder capsule over time.
As a foundational mechanism, MSC paracrine activity in injured and inflamed tissue has been well-characterized as an “injury drugstore” effect- where the cells release a range of regenerative signals in response to local damage cues (Caplan & Correa, Cell Stem Cell, 2011).
What Does the Evidence Say?
Specific clinical trials on MSC injection for adhesive capsulitis remain limited- this is a developing area of research. The evidence that exists draws from:
- Studies of biologic injections (PRP and MSCs) in shoulder and capsular conditions, which suggest that growth factor-rich preparations can reduce inflammation and improve outcomes in chronic shoulder pathology (Dallaudière et al., J Vasc Interv Radiol., 2014)
- The established biology of MSCs as anti-inflammatory and anti-fibrotic agents, which provides a mechanistic rationale for their use in a fibrotic capsular condition
- Clinical experience from regenerative medicine practitioners with intra-articular MSC injection for shoulder pathology, including early-phase reports of favorable tolerability and pain reduction
Broader research on responders to biologic therapies in joint conditions supports the premise that anti-inflammatory and regenerative injections can meaningfully reduce pain and improve function in appropriate candidates (Milants et al., Biomed Res Int., 2017).
Larger controlled trials specific to adhesive capsulitis are needed, and patients should understand that stem cell therapy for this indication remains investigational.
What Treatment Typically Involves
For patients pursuing MSC-based therapy, the process includes:
Clinical evaluation: Assessment of shoulder range of motion, pain levels, and stage of adhesive capsulitis. Ultrasound or MRI may be used to assess capsular changes.
MSC preparation: Cells are harvested from bone marrow aspirate (BMAC) or adipose tissue, then processed and concentrated.
Injection: MSCs are injected into the glenohumeral joint and, where appropriate, along the rotator interval under imaging guidance.
Rehabilitation: Physical therapy is continued after treatment to take advantage of the regenerative window and progressively restore range of motion.
Results vary and are influenced by the stage of the condition at the time of treatment, the presence of underlying conditions like diabetes, and adherence to post-treatment rehabilitation.
Frequently Asked Questions
Can stem cell therapy completely resolve frozen shoulder?
Stem cell therapy aims to reduce the inflammatory and fibrotic drivers of adhesive capsulitis, which may accelerate recovery and improve range of motion. Whether it fully resolves the condition depends on factors including disease stage, duration, and individual response.
Is stem cell treatment painful for frozen shoulder?
The injection is typically performed with local anesthesia. Some mild discomfort and soreness at the shoulder are expected after treatment and usually resolve within a few days.
How soon can I start physical therapy after stem cell injection for frozen shoulder?
Most practitioners recommend beginning gentle physical therapy within 1–2 weeks of injection, with a gradual progression of stretching and range-of-motion exercises as tolerated.
Should I try cortisone injections before stem cell therapy?
Corticosteroid injections are generally recommended as an earlier intervention in the freezing and early frozen stages. Stem cell therapy may be more relevant for patients who have not responded adequately to conventional approaches or who are seeking a regenerative rather than purely anti-inflammatory option.
Key Takeaways
- Frozen shoulder involves progressive capsular fibrosis and inflammation that restricts shoulder movement
- This treatment option targets the fibrotic and inflammatory processes through MSC paracrine mechanisms
- MSCs release anti-inflammatory and anti-fibrotic signals that may help modify the capsular environment
- Evidence is emerging and the approach remains investigational; larger clinical trials are underway
- Treatment typically involves intra-articular MSC injection followed by progressive physical therapy
- Patients in the frozen or early thawing stage may be most appropriate for regenerative approaches
To find out whether stem cell therapy at Ways2Well may be appropriate for your shoulder condition, schedule a stem cell therapy consultation or schedule a consultation with our medical team.
References
- Neviaser AS, Hannafin JA. “Adhesive capsulitis: a review of current treatment.” Am J Sports Med. 2010;38(11):2346–2356. DOI: https://doi.org/10.1177/0363546509348048
- Caplan AI, Correa D. “The MSC: An injury drugstore.” Cell Stem Cell. 2011;9(1):11–15. DOI: https://doi.org/10.1016/j.stem.2011.06.008
- Dallaudière B, Pesquer L, Meyer P, et al. “Intratendinous injection of platelet-rich plasma under US guidance to treat tendinopathy: a long-term pilot study.” J Vasc Interv Radiol. 2014;25(3):334–341. DOI: https://doi.org/10.1016/j.jvir.2013.11.011
- Milants C, Bruyère O, Kaux JF. “Responders to platelet-rich plasma in osteoarthritis: a technical note.” Biomed Res Int. 2017;2017:2176138. DOI: https://doi.org/10.1155/2017/2176138
Author: Ways2Well Editorial Team
Reviewed by: Scientific Advisory Board member