Fractures in children through abnormal bone take on some unusual characteristics. The bone lesion could be a cyst, a tumor, or infection. In all cases, the fracture is influenced by the lesion and vice versa. Surgeons treating children with bone fractures through abnormalities must take into consideration all aspects of both the fracture and the lesion.
Some problems like fibromas (soft, benign tumor made up of connective tissue) tend to go away on their own. Even if they don’t disappear, they are relatively harmless and don’t have to be removed. Other lesions such as fibrous dysplasia (weak patches of bone with poorly organized cells) are treated differently depending on the child’s age, size of the affected area, and location of the fracture.
These are just two examples of the types of benign bone lesions linked with bone fractures discussed in this review article from the Department of Orthopaedics and Rehabilitation at Yale University. Once the fracture and other suspicious looking lesion(s) have been seen on X-ray, then other imaging such as CT scans, MRIs, or bone scans may be necessary. CT scans show the details of bone, whereas MRIs are much better for seeing specifics of soft tissues. Bone scans are usually reserved for patients who might have cancer that has spread elsewhere. Less often, a biopsy of the involved tissue is taken and analyzed in a lab.
Treatment is aimed at both problems either one at a time or both at the same time. How aggressive treatment is depends on several factors. That’s where knowledge of the different types of bone lesions helps assist the surgeon in determining the best approach to management of the condition. Knowing the natural history (what happens over time without treatment) helps guide treatment decisions. Likewise, having some idea of the usual prognosis (final outcomes with and without treatment) is important, too.
Let’s take a look at some of the benign lesions presented in this article. Besides fibromas and fibrous dysplasia already mentioned, there are also unicameral and aneurysmal bone cysts. Malignant bone tumors such as osteosarcoma, fibrosarcoma, and chondrosarcoma are also possible problems associated with bone fractures but these are not the focus of this article.
Bone cysts are spaces filled with some type of fluid. Unicameral bone cysts are often close to the growth plate next to a joint. They tend to fill up with synovial (joint) fluid. Aneurysmal bone cysts are more likely to be filled with blood. The cause of bone cysts remains unknown but there are some theories. Sluggish flow and congestion of fluids, trauma, and local disturbances in blood circulation are some of the more likely causes. There is evidence to support each one of these ideas. Molecular and genetic theories exist as well.
Knowing how bone cysts develop may help with prevention but once they appear, treatment is based more on the natural history and prognosis. Unlike fibromas that often go away without treatment, bone cysts must be removed surgically. Left alone, they will just get bigger and increase the risk of another bone fracture. If the cyst is large enough, it may be necessary to fill in the empty space (after removal) with a bone graft.
Aneurysmal bone cysts tend to come back after surgical removal. Efforts are being made to find effective ways to kill any unseen cells left behind. Liquid nitrogen, phenol, and argon beam coagulation are three examples of treatments used to prevent recurrence. Only a very wide resection of aneurysmal bone cysts has a zero per cent chance of recurrence. Other methods under investigation include arterial embolization. This is a way of injecting blood clots into the blood vessel to close it down and prevent further bleeding.
In summary, bone fractures in the presence of bone abnormalities require a different treatment approach than a simple fracture. The surgeon must examine the lesion as closely as possible with imaging and create a plan of care based on the child’s age, type of fracture, type of bone lesion, including the natural history and prognosis for that lesion. Even though these bone abnormalities are considered “benign” (meaning they aren’t cancerous and won’t kill the patient), they can still cause quite a bit of damage and deformity. Therefore they must be handled carefully in order to get the best results.