Introduction
Benign tumors are non-cancerous growth that grows within the bone tissue. They can lead to progressive pain, and some cases may need treatment to prevent bone damage, while others may require no treatment. These tumors typically affect younger ones. Most bone tumors originating in bones are benign, indicating they do not spread to other sites. These tumors can develop in any bone and at any location within the bone.
They usually occur in larger bones like the tibia, femur, pelvis, humerus, ribs, and spine. Certain types of tumors are common in certain regions, such as the spine or near the growth plates in the knee, hip, or shoulder. Most prevalent types of bone tumors are osteochondromas, enchondromas, non ossifying fibromas, osteoid osteomas, chondroblastoma, periosteal chondromas, osteoblastomas, giant cell tumors, and chondromyxoid fibromas.
What Are the Symptoms of Orthopedic Tumors?
Bone tumors occur when bone cells proliferate uncontrollably, resulting in the formation of a lump or mass of cells. The exact cause of these tumors is still unknown. Symptoms of benign orthopedic tumors include:
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Noticeable swelling in the affected area.
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Pain may be severe and intensify over time and can be persistent even during rest.
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Increased susceptibility to fractures or breaks in the bone that can be worsened by the presence of a growing tumor.
What Are the Characteristics of Osteoid Osteoma?
A bone-forming tumor, known as a benign osteoblastic tumor, makes up 12 % of non-cancerous bone tumors. It can occur at any age, even before three years of age, but it is usually seen in the second decade of life and is more common in boys. These tumors are usually solitary, but there have been infrequent cases of multiple occurrences. They consist of a small core surrounded by dense tissue, generally less than 0.59 inches wide. Larger lesions may be categorized as osteoblastomas, which have similar appearances and genetics. The distinction between these two types of tumors is still a debatable topic among scientists. Bone-forming tumors usually affect the long bones of the lower limbs, although they can also occur in the spine, especially in the lower back.
What Are the Characteristics of Osteoblastoma?
Osteoblastoma, constituting roughly 14 % of non-cancerous bone tumors, is a bone-forming growth that usually affects young adults, with an average of 20 years, and it is typical in males more than three times compared to females. The tumor tends to be more aggressive with older age at diagnosis. Similar to osteoid osteomas, osteoblastomas have a similar central core surrounded by tissue.
Osteoblastomas differ from osteoid osteomas in many ways, as they have a more vascularized core and a less organized structure. Unlike osteoid osteomas, they do not lead to the production of prostaglandins and have fewer nerve fibers. Typically, osteoblastomas have an average diameter of around 1.18 inches but can grow as large as 5.91 inches. Like many other benign tumors, osteoblastoma exhibits slow growth and may not cause symptoms in most patients. This peculiar characteristic can assist in distinguishing it from osteoid osteoma. However, when symptoms occur, they often include dull, localized pain with soft tissue swelling.
What Are the Characteristics of a Giant Cell Tumor?
Giant cell tumors can make up approximately 15 to 20 % of non-cancerous bone growths in Western countries. Unlike many other benign tumors, they can metastasize, usually to the lungs, and are locally aggressive, leading to bone loss (osteolysis). They usually occur in young adults, typically around their third decade of life. Patients with this condition typically experience pain, which is the most presenting symptom. Tenderness, swelling, and joint swelling may be observed during physical examination. Patients may also show an antalgic gait due to discomfort. Pathological fractures involving the joints can indicate the presence of the tumor.
What Are the Characteristics of Osteochondroma?
Osteochondroma is the most prevalent benign bone tumor, comprising up to 20 to 50 % of such cases and 10 to 15 % of all tumors. Most commonly, it occurs in bones that are still growing, with some research suggesting its origin from the growth plate at the end of bones. Osteochondromas are more frequent in males than females and appear as bony protrusions covered by cartilage on the bone's outer surface.
They can occur as single or as multiple lesions in a condition called multiple hereditary osteochondromas. Single osteochondromas, which are approximately 85 % of cases, usually develop around the age of 20. It is believed these tumors may originate from a growth plate fragment pushing through the periosteum, forming a sessile or pedunculated lesion. This protrusion can occur spontaneously, post-trauma, or through radiation exposure.
What Are the Characteristics of Enchondroma?
Enchondroma is a benign tumor originating from the cartilage tissue within the bone’s medullary cavity, basically composed of hyaline cartilage. It is the second most common noncancerous primary bone tumor after osteochondroma, accounting for about 3 to 10 % of all bone tumors and 13 % of noncancerous bone tumors. It usually appears between ages 15 and 35, with no gender predilection. Approximately 40 % of cases occur as a result of sporadic mutation in genes called isocitrate dehydrogenase-1 and isocitrate dehydrogenase-2.
About 90 % of enchondromas are solitary growths that typically arise from cartilage cells located within the bone’s medullary cavity. These tumors are known to develop from remnants of growth plate cartilage trapped during bone growth. The trapped cartilage cells or chondrocytes maintain their cartilaginous characteristics instead of maturing into bone cells. Enchondromas usually do not cause symptoms and may be found incidentally during medical examination. However, if the tumor causes a pathological fracture or undergoes malignant transformation, it can result in pain.
Conclusion
Benign orthopedic tumors are usually encountered in clinical practice, particularly among young patients. Recognizing these tumors is important for clinicians as they share common features, symptoms, and appearance. Accurate identification of these tumors is vital to avoid misdiagnosis, which can significantly impact the treatment plan for patients. Significant progress has been made in understanding these lesions, but many questions remain unanswered. Continued research is needed to perceive the unresolved aspects of benign bone tumors.
