Approach to Pathologic Fractures in Children

Abstract and Introduction

Abstract

The pediatric population poses diagnostic and treatment challenges in orthopaedics, and the complication of a pathologic process affecting the bone adds to those challenges. This paper focuses specifically on pathologic fractures related to tumors, although weakness in the bone can be attributable to multiple etiologies. To treat these fractures appropriately, a comprehensive approach must be used. Pathologic fractures can result from both benign and malignant conditions. For most benign lesions, standard fracture care and conservative management may be applied. Malignant lesions may present or be associated with a pathologic fracture, and although in the past the presence of a pathologic fracture may have precluded limb salvage, currently substantial evidence exists to the contrary. The most common benign and malignant lesions associated with pathologic fractures are further discussed.

Introduction

Because of their high levels of activity, children and adolescents are prone to musculoskeletal injuries, including fractures. Inherent structural abnormality of the bone from a pathologic process increases the risk of fracture. Weakness in the bone can be attributable to multiple etiologies, but this paper focuses specifically on pathologic fractures related to tumors. To treat these fractures appropriately, a comprehensive approach must be used, and attention to detail is paramount.

The history should include information about:

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  The patient's age: certain musculoskeletal tumors are associated with specific age groups.
  
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  The mechanism of injury, specifically whether high- or low-energy trauma was involved or if there was an absence of trauma.
  
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  Pain before or after injury, including characterization of pain and aggravating or alleviating factors.
  
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  Medical history: it is important to note any oncologic history or if there is any family history remarkable for musculoskeletal neoplasms, or related syndromes.
  
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  Review of systems.
  

The physical examination should cover:

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  Examination of the skin, which can direct diagnosis to an underlying systemic illness such as neurofibromatosis or McCune-Albright disease and rule out infection.
  
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  Neurovascular examination.
  
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  Soft-tissue involvement to include the size of the lesion and characteristics such as mobility, adherence to skin, overlying skin changes.
  
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  Full extremity examination.
  
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  Systemic examination, including the lymph nodes as well as abdominal and pelvic palpation.
  

After appropriate history and physical examination, imaging studies are reviewed. Plain radiographs can offer a significant amount of information and can determine if further imaging studies, like MRI, are needed. The following should be evaluated on the imaging studies:

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  Location of the lesion: specific tumors occur more often in certain bones and within specific areas of that bone.
  
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  Size and extent of the lesion: aggressive lesions often are large and fast growing. A more aggressive or malignant lesion will have a less-defined zone of transition within the bone.
  
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  Effect on the bone: the lesion should be characterized as lytic, blastic, or mixed. This is particularly important when evaluating the risk for pathologic fracture because a lytic lesion is more likely to predispose to fracture.
  
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  Bone's response: if the bone has time to respond to the destructiveness of the lesion and cortical thickening results, this may offer some containment of the lesion and "protect" from a pathologic fracture.
  
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  Soft-tissue component: the presence of a soft-tissue mass may indicate a malignancy.