Chondroblastoma, Causes and Symptoms
Chondroblastoma is a rare tumor that accounts for approximately 1% of all bone tumor cases in the United States. This tumor is usually benign, but requires treatment to avoid long-term effects. It typically originates at the ends of the long bones in the body. Approximately 72% of cases of chondroblastomas are seen in the bones in the lower half of the body, including the femur, knee, and tibia. Other areas affected are the upper arm bones and shoulder areas.
Chondroblastomas are almost only seen in patients under the age of 25, in bones that are still growing. Males have been shown to be nearly twice as likely to have a chondroblastoma as females. Without treatment, this bone tumor can cause muscle deterioration and reduced joint mobility. It is a benign tumor, but it can be aggressive, potentially reaching a large size with a prominent inflammatory reaction. Despite being benign, chondroblastomas have the potential to involve multiple bones or to metastasize the lungs.
Anatomy of the Long Bone
The bone is a complex element of the body, which can be divided up into three sections consisting of the following:
- The epiphysis – This is found on the end of the bone, where spongy cancellous tissue is covered by the articular cartilage.
- The metaphysis – This is the area that contains the growth plate, responsible for rapid increase in length during childhood and adolescence.
- The diaphysis – This is the long part of the bone consisting of a strong outer tube (cortex) for support, and a soft central component, largely composed of bone marrow.
The bone, while it protects vital organs and is one of the most resilient parts of the body, is also one of the body’s most complicated components. Because of the multitude of functions that must be performed by the skeletal system and how closely each bone interacts with other parts of the body, long bones in particular are susceptible to contracting diseases.
Types of Chondroblastoma
Here some facts on the varying types of chondroblastoma:
- Chondroblast – The chondroblastoma tumor is derived from chondroblasts, which is how it received its name. Chondroblasts are immature cartilage-forming cells. In chondroblastomas, they are unable to make normal cartilage, however.
- Metastasis of Chondroblastoma – Rarely, cells from a chondroblastoma can metastasize and spread to other areas of the body, most commonly the lungs. These cases indicate a particularly aggressive form of the disease.
Causes of Chondroblastoma
There is still an immense amount of research to be done on this rare disease, so the causes of chondroblastoma are still relatively unknown. Here are some of the basic known facts researchers have discovered so far:
- Immature cell production – When chondroblasts occur, it is typically in younger bones that are still developing.
- Trauma – Many times when the bone has been damaged or experienced significant trauma, some unforeseen complications may be encountered during recovery. In rare occasions, chondroblasts may occur while the bone is repairing itself, which some speculate can cause chondroblastoma.
Symptoms of Chondroblastoma
There are a variety of symptoms that go along with chondroblastoma. Most patients experience pain in their bones prior to any of the more severe symptoms that go along with this rare disease. Keep in mind that everyone’s body reacts differently to the disease, so it is important to seek the help of a professional.
The following are some of the most common chondroblastoma symptoms.
- Localized pain
- Joint pain
- Reduced joint mobility
- Joint swelling
- Swelling and tenderness at the end of long bones
- Unexplained bone fractures
Chondroblastoma symptoms are also common in other bone diseases, making it difficult to diagnose. Consult your doctor to have X-rays and other tests done to determine the cause of your symptoms.
The multidisciplinary team of orthopaedic experts at North Shore-LIJ Orthopaedic Institute's musculoskeletal oncology services in New York treats Chondroblastoma as well as a broad range of conditions that affect the bones within the body.