Identifying a Major Pain-Generator in Some Arthritis Cases
Joint pain and dysfunction are common ailments affecting people of all ages, leading to a significant orthopedic burden. Advanced imaging techniques, like magnetic resonance imaging (MRI), are essential for evaluating joint dysfunction. MRI provides detailed views of all joint components, including cartilage, bone, and ligaments.
Recent research has highlighted the importance of subchondral bone and marrow signal alterations in diagnosing and managing both trauma and arthritis. Modern treatment strategies now focus on addressing both cartilage and bone issues to preserve joint health and restore function. Bone marrow signal abnormalities are often associated with patient symptoms, cartilage loss, and disease progression. Understanding the anatomy and biomechanics of the chondro-osseous junction is crucial for interpreting these marrow signal abnormalities and their clinical implications.
A Breach in the Protective Layer
The subchondral bone plate, a zone separating articular cartilage from the marrow cavity, plays a vital role in joint health. It comprises a superficial layer of calcified cartilage and a deeper layer of lamellar bone, separated by a thin cement line. The tidemark, a distinct band of mineralized cartilage, connects the bone plate to the cartilage. This complex structure contributes to the unique biomechanical properties of the chondro-osseous junction.
The subchondral bone’s primary function is to support and protect the overlying articular cartilage. It acts as a shock absorber, distributing mechanical forces across the joint. Changes or damage to the cartilage can lead to altered biomechanics and osseous pathology, visible on MRI.
How do BMLs show up on MRI?
Increased T2 marrow signal or hyperintense signal on MRI within the subchondral bone can indicate various conditions, including arthritis, osteonecrosis, stress fractures, and infection. These show up as “spots” deeps in the bone in the typically spongy marrow area and are a mix of a watery substance and blood. In osteoarthritis, these signal changes are often referred to as bone marrow lesions (BMLs). BMLs are associated with pain, cartilage loss, and disease progression. Their presence, size, and location can provide valuable insights for treatment planning and prognosis.
Common areas that tend to reveal changes to the marrow are: knee, hip, shoulder, wrist, and ankle. These are very common in load bearing areas in the body due to the chronic changes in the protective cartilage layers.
How Are Bone Marrow Lesions Treated?
The gold-standard procedure for BMLs are called bone augmentations or “bone augs” for short, meaning the Regenexx physician injects directly into the bone marrow lesion, typically using bone marrow concentrate (BMC). Some of the most compelling and longitudinal studies in the realm of orthobiologics strongly demonstrate the clinical efficacy of using Bone Marrow Concentrate (BMC) in a bone augmentation procedure. Specifically in the knee, knees treated with bone augmentation procedures were compared against those treated with procedures injecting into the joint space alone. After 15 years, those treated with bone augmentation had better outcomes as compared to the joint space procedure counterparts.
The Takeaway?
Bone marrow lesions are all too often overlooked or left untreated in conventional orthopedics. The great news is there is a clear path in regenerative medicine to treat these painful lesions. If you or someone you know if struggling with how to manage the type of pain mentioned in this blog or BMLs found on an MRI, please contact us to meet on person or virtually with one of our Regenexx Physicians in Tampa, Orlando, St. Petersburg, or Sarasota.