Introduction:
Rotator cuff tears are the most common cause of shoulder pain and dysfunction. The rotator cuff is a group of tendons that support the shoulder joint. It is estimated that ~ 30%-50% of the population over the age of 50 has some form of rotator cuff pathology. Conservative treatments can sometime help with symptoms, but progression of tendon degeneration occurs in most cases. Even surgery does not halt the degeneration and comes with a high rate of repeat tears.
Luckily, new shoulder treatments using bone marrow and adipose stem cells are now available. Both bone marrow and adipose (fat) tissue are rich in stem cells that can be used for regenerative medicine treatments. When stem cells are injected, they release growth factors that stimulate tissue healing. Both animal and human studies have shown that stem cells are safe and effective treatments of many musculoskeletal conditions. Below is a summary of two studies that highlight the use of stem cells to heal torn rotator cuff tendons.
Adipose Stem Cells Study
In 2017, Dr. Hyunchul Jo and colleagues published the results of their stem cell study in the Journal of Arthroscopic & Related Surgery. Nineteen patients who had partial thickness rotator cuff tears were treated with ultrasound guided injections of adipose (fat) derived stem cells at different concentrations. After the injection, the patients were followed for two years and assessed for pain, strength and function. The size of the tear was also assessed using MRI imaging.
The average pain scores decreased by about 40% – 60% at 3 months and further decreased to almost no pain at 6 months and at 1 year. Their strength and function also significantly improved at 6 months and 1 year. The pain improvement was maintained at the 2 year follow up, while their function improved even further. There were no complications related to the rotator cuff treatment during the study.
Bone Marrow Stem Cells Study
In 2020, Dr. Centeno and colleagues published the results of their study in the medical journal Stem Cells International. Twenty-five patients with partial or full thickness rotator cuff tears were randomized to either an exercise group or an injection group. The patients in the injection group received an ultrasound guided injection of bone marrow stem cells and PRP into the injured tendon. The exercise group received 3 months of specific shoulder exercises under the instruction of a physical therapist. The patients in the exercise group were allowed to cross over to the injection group at 3-6 months. The patients were followed for 2 years and assessed for pain and function (shoulder disability scores). Some of the patients had a repeat MRI of the shoulder at 1 year to assess the tendon tear.
The average pain and disability scores dropped by >50% at 3 months and kept on improving during the 2 year follow-up. All but one patients from the exercise group crossed over to the stem cell injection group. About half of the patients received an additional “touch up” platelet rich plasma (PRP) injections at ~ 6-7 months from the initial injection. The MRI images at 1 year showed significant tendon healing in 14 out of 15 patients studied. There were no complications related to the treatments during the study.
Conclusion
Rotator cuff tendon tears are the most common cause of shoulder pain. Ultrasound guided injections of bone marrow and adipose derived stem cells are safe and effective treatments for rotator cuff tears. An injection of stem cells can help heal tears of the rotator cuff tendons, this can provide long term relief of pain and improvement of shoulder function. A stem cell treatment of the shoulder is a reasonable alternative to shoulder surgery.
References:
- Jo, Chris Hyunchul, et al. “Intratendinous injection of mesenchymal stem cells for the treatment of rotator cuff disease: a 2-year follow-up study.” Arthroscopy: The Journal of Arthroscopic & Related Surgery 36.4 (2020): 971-980
- Centeno, Christopher, et al. “A randomized controlled trial of the treatment of rotator cuff tears with bone marrow concentrate and platelet products compared to exercise therapy: a midterm analysis.” Stem cells international 2020 (2020).
