Why Do We Get Frozen Shoulders?


Frozen shoulder, also called adhesive capsulitis, is often called “idiopathic” which means the cause is not known or it arises spontaneously. I have wondered through my many years as a physical therapist if the cause would ever be found and why it seems to primarily occur in women. At a recent course I attended in St. Louis, the presenter, Dora Partridge, a Texas physical therapist, had some interesting views to the “whys”. She questioned the role of hormones, especially estrogen, in this process.


Research has shown that estrogen is a powerful hormone stimulating the building of new bone, promoting muscle growth and repair, maintaining the integrity of the connective tissue, reducing inflammation and overall facilitating the healing process in addition to its more well know affects (reducing hot flashes, night sweats and vaginal dryness). Though she discussed other underlying conditions that have been connected to frozen shoulder, such as diabetes and thyroid dysfunction, she felt that estrogen levels had been ignored.


Over a four-year period she collected data on 69 female patients diagnosed with frozen shoulder. She requested that they all have their serum estradiol levels tested and found that 59 of the 69 were estrogen deficient. As to date, there are no medical journal reviewed  studies to support the effect of estrogen on frozen shoulders, so not all of the doctors of these patients would agree to prescribe estrogen replacement therapy.


Overall what she found in the estrogen replacement group was –

  • Many women obtained pain relief within 24 hours of initiating estrogen replacement.
  • For most of the women it took 2 weeks of initiating estrogen replacement to see significant improvement in their frozen shoulder symptoms
  • The response time depended on how long they had been estrogen deficient with younger women turning around more rapidly than older women.

Both the estrogen replacement and non-treated group received the same physical therapy but the untreated group progressed much slower with continued inflammation with difficulty gaining muscle mass and overall strength.


Hopefully there will be further research on this subject in the future. In the meantime, it is something to think about.


This information is presented by Barbara Casey, PT.  If you have any questions about a frozen shoulder please contract her at our office number on the right.