Orthopedics Fractures & Broken Bones Understanding Bone Bruise or Marrow Edema By Jonathan Cluett, MD Jonathan Cluett, MD Verywell Health's LinkedIn Verywell Health's Twitter Jonathan Cluett, MD, is a board-certified orthopedic surgeon with subspecialty training in sports medicine and arthroscopic surgery. Learn about our editorial process Updated on August 11, 2022 Medically reviewed by Stuart Hershman, MD Medically reviewed by Stuart Hershman, MD Verywell Health's LinkedIn Stuart Hershman, MD, is board-certified in orthopaedic surgery. He is the director of adult spinal deformity & complex spinal reconstruction at Massachusetts General Hospital and is on the faculty at Harvard Medical School. Learn about our Medical Expert Board Print The words "bone bruise" describe a condition also known as bone marrow edema or bone contusion. Many patients find these words confusing. What does it mean to have a bone bruise? Sigrid Gombert / Getty Images Bone Bruise There is controversy about exactly what a bone bruise is. Are they all the same, and why do they occur? Prior to MRIs being performed, there was no test for a bone bruise, and, therefore, the condition was not well recognized. When MRI tests started to be performed, doctors were able to "see" an abnormality in the bone that was described as bone bruising. A bone bruise is thought to occur when there is a microscopic fracturing of the internal bone structure. While these microfractures don't significantly weaken the bone, they can cause bleeding and inflammation within the bone. This can lead to pain and symptoms similar to a more familiar soft-tissue bruise. The most appropriate way to refer to this finding on an MRI is "bone marrow edema." How Serious Is Bone Marrow Edema? Causes There are three main reasons why people get bone marrow edema, but, in essence, anything that causes added stress to the bone will cause edema. Traumatic Injury Trauma is a common cause of bone marrow edema. The trauma may be the result of repetitive overuse, or it may be the result of an acute injury. One of the most common causes of a bone bruise seen on a knee MRI is a ligament injury such as an ACL tear. When the ACL is torn, the bones suddenly shift, causing a compression injury and a very specific pattern of bone marrow edema. In fact, when MRIs were less clear and the ACL was harder to visualize, doctors looked for this pattern of bone bruise to diagnose a torn ACL. Today's MRIs are much better quality, and seeing the torn ACL is much easier, but the bone bruise pattern is still helpful to confirm the injury. An Overview of ACL Tears Arthritis Arthritis causes damage to the cartilage surface of the joint. This protective surface helps to shield and cushion the underlying bone. When this cartilage surface is damaged or worn, the bone around the joint may be exposed to higher stress and may succumb to the increased burden, causing edema to occur. Patients with arthritis often have evidence of bone bruising in the areas most affected by their condition. Types of Arthritis and Rheumatic Diseases Osteonecrosis Osteonecrosis is a specific condition that causes interruption of the blood supply to the bone. The lack of blood flow can lead to weakening of the bone. If the bone becomes weak, it may sustain microfractures from lack of strength in the structure of the bone. These microfractures may cause bone marrow edema surrounding the area of osteonecrosis. Osteonecrosis (Avascular Necrosis) Explained Treatment Damaged bone needs rest and relief from stress. When bone bruising is seen on an MRI, the bone is damaged and should be allowed to heal. It is very difficult to predict how long bone bruising will take to resolve, and there are some conditions where the bone bruising may be indefinitely persistent. The bone bruising seen after an ACL tear may be present for several months after the injury, and the bone bruising of arthritis or osteonecrosis may persist so long as those conditions are present. Most surgeons recommend limiting activity when bone bruising is found around a joint. In these cases, there is often concern about damage to the cartilage of the joint. Further damage to the bone supporting the cartilage can lead to a condition called post-traumatic arthritis. Therefore, most orthopedists will recommend allowing the symptoms of a bone bruise to completely resolve before resuming athletic activity. 5 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Uçar BY, Necmioğlu S, Bulut M, Azboy I, Demirtaş A, Gümüş H. Determining bone bruises of the knee with magnetic resonance imaging. Open Orthop J. 2012;6:464–467. doi:10.2174/1874325001206010464 Mandalia V, Henson JH. Traumatic bone bruising--a review article. Eur J Radiol. 2008;67(1):54-61. doi:10.1016/j.ejrad.2008.01.060 Wildi LM, Raynauld J-P, Martel-Pelletier J, Abram F, Dorais M, Pelletier J-P. Relationship between bone marrow lesions, cartilage loss and pain in knee osteoarthritis: results from a randomised controlled clinical trial using MRI. Annals of the Rheumatic Diseases. 2010;69(12):2118-2124. doi:10.1136/ard.2009.127993 Marcacci M, Andriolo L, Kon E, Shabshin N, Filardo G. Aetiology and pathogenesis of bone marrow lesions and osteonecrosis of the knee. EFORT Open Rev. 2017;1(5):219–224. doi:10.1302/2058-5241.1.000044 Boks SS, Vroegindeweij D, Koes BW, Bernsen RMD, Hunink MGM, Bierma-Zeinstra SMA. MRI Follow-Up of Posttraumatic Bone Bruises of the Knee in General Practice. American Journal of Roentgenology. 2007;189(3):556-562. Additional Reading Boks SS, Vroegindeweij D, Koes BW, Bernsen RMD, Hunink MGM, Bierma-Zeinstra SMA. MRI Follow-Up of Posttraumatic Bone Bruises of the Knee in General Practice. American Journal of Roentgenology. 2007;189(3):556-562. Mandalia V, Henson J. Traumatic bone bruising—A review article. European Journal of Radiology. 2008;67(1):54-61. Marcacci M, Andriolo L, Kon E, Shabshin N, Filardo G. Aetiology and pathogenesis of bone marrow lesions and osteonecrosis of the knee. EFORT Open Rev. 2017;1(5):219–224. Uçar BY, Necmioğlu S, Bulut M, Azboy I, Demirtaş A, Gümüş H. Determining bone bruises of the knee with magnetic resonance imaging. Open Orthop J. 2012;6:464–467. doi:10.2174/1874325001206010464 Wildi LM, Raynauld J-P, Martel-Pelletier J, Abram F, Dorais M, Pelletier J-P. Relationship between bone marrow lesions, cartilage loss and pain in knee osteoarthritis: results from a randomised controlled clinical trial using MRI. Annals of the Rheumatic Diseases. 2010;69(12):2118-2124. doi:10.1136/ard.2009.127993. By Jonathan Cluett, MD Jonathan Cluett, MD, is board-certified in orthopedic surgery. He served as assistant team physician to Chivas USA (Major League Soccer) and the United States men's and women's national soccer teams. See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit