Case Report by Dr. Jeffery Rusten Bennett, MD
Musculoskeletal Imaging Fellowship, Duke University 2007
General Radiology Residency, Duke University 2006
Background:
Anterior cruciate ligament (ACL) rupture and meniscal injuries are significant contributors to knee instability, especially in older adults. Surgical intervention is often contraindicated in this population due to age-related risks. Conservative management—ranging from physical therapy and chiropractic care to emerging regenerative modalities—has gained attention as a viable alternative. RheeGen is a novel, non-invasive transdermal product containing bioactive biomolecules derived from human mesenchymal stem cells, formulated to support tissue recovery and reduce inflammation. This case report highlights the use of RheeGen in combination with red light therapy (photobiomodulation) in a patient with longstanding ACL deficiency and a newly diagnosed lateral meniscus tear, demonstrating notable clinical improvements.
Case Presentation:
A 74-year-old white female with no comorbidities, normal body weight, and a physically active lifestyle presented with a chronic history of left knee instability. The original injury occurred in 2015 following a motor vehicle accident, resulting in a complete ACL rupture confirmed by MRI. Surgical intervention was not pursued due to age, and the patient recovered functionally through physical therapy and cold laser therapy over six months.
In February 2024, the patient sustained a reinjury to the same knee while dismounting a bicycle. The mechanism involved a torsional movement as she pivoted on her stationary left foot while lifting her right leg over the bicycle frame, resulting in an audible pop and immediate, severe pain. She became unable to bear weight on the left leg.
Over eight months, the patient progressed from a knee scooter to a walker, then a cane, but her recovery plateaued. An MRI on October 4, 2024 revealed:
- Full-thickness lateral meniscus tear at the popliteal hiatus
- Marked partial-thickness tear with extrusion of the body segment
- Absence of identifiable ACL fibers
Conservative therapies were initiated, including physical therapy and chiropractic care targeting a suspected loose body fragment. Shock wave therapy was considered but not available locally. The patient remained functionally limited.
Intervention and Outcome:
On March 13, 2025, the patient initiated topical therapy with RheeGen, applying the regenerative cream transdermally over the lateral meniscus and popliteal region. During the first week, she experienced a transient worsening of symptoms, including increased swelling, reduced range of motion (ROM), and decreased ambulation.
On March 18, 2025, she incorporated red light therapy (LED) concurrently, continuing topical application of RheeGen over the affected regions. By March 22, 2025, she reported:
- A marked decrease in swelling, especially in the popliteal fossa
- Improved ROM in the affected knee
- Normalization of gait mechanics, with no increase in pain following higher levels of physical activity
These outcomes represented the first substantial improvement after several months of stagnation despite conventional therapies.
Conclusion:
This case demonstrates the potential utility of RheeGen, a stem cell-derived topical product, in combination with photobiomodulation, in the conservative management of chronic ACL deficiency and degenerative meniscal injury in an elderly patient. The observed improvements in mobility, inflammation, and function following this integrative intervention suggest a possible therapeutic role for regenerative topicals in orthopedic rehabilitation. Further investigation, including controlled clinical studies, is warranted to validate these findings and elucidate mechanisms of action.
