Femur fracture occuring on a pathological bone.
The patient complained of intense pain in the left leg after a fall. An X-ray of the left femur was performed.
The radiogram revealed a transverse incomplete cortical fracture of the distal femur. The other features seen are a bowing deformity of the bone, a coarse demineralisation with widening of the bone and thickened cortex. There is also a thickening of the trabecular pattern.
The most likely diagnosis is a stress fracture occuring in a pagetic long bone.
Paget's disease (PD) is a relatively common disease occuring in approximately 3-4% of people over 40 years of age. Most patients are mildly symptomatic or asymptomatic. No clear aetiology is known.
Pathologically, the disease occurs in three phases. Initially, bone is resorbed secondary to increased osteoclastic activity. Osteoblasts then form abnormal new bone. The primitive woven bone production is disorganised, contains increased vascularity and connective tissue, and does not contain Haversian systems. These two phases are repeated until the osteoclastic activity subsides. The final, or inactive phase is reached when there is a cessation of osteoblastic activity. The disease usually involves more than one bone although 10-35% of patients have monostotic disease.
The three distinct radiographic phases (lytic, mixed and sclerotic) correspond to the pathological phases. In the lytic phase, most commonly recognised in the skull as osteoporosis circumscripta and in long bones, a purely lucent defect is noted. As the disease progresses, through the mixed, to the inactive sclerotic phase, new pagetoid bone enlarges the bone predominantly through cortical apposition. Coarse and thickened trabeculae are also noted and in the skull a "cotton wool" appearance may be seen. In the inactive or sclerotic phase, a diffuse increase in bone density as well as bone enlargement is noted.
The long bone most frequently involved in Paget's disease is the femur, but the clavicles, the scapula, and the fibula may also be involved. The sternum, patella and the bones of the hands and feet are rarely involved.
In the long bones, the initial osteolytic lesion usually starts in the subarticular region of the epiphysis and extends toward the diaphysis with a well-demarcated V-shaped zone ("blade of grass") separating the normal and abnormal bone. With progression of the disease, the radiograms reveal:
Pagetic disease of the femur
Based on the provided X-ray images, the following characteristics can be observed:
These imaging features suggest chronic, long-term bone remodeling in the femur, with a fracture occurring in a pre-existing compromised area, consistent with a “pathological fracture.”
Considering the patient’s history (70 years old, possibility of prolonged abnormal bone remodeling) and the imaging findings, the following differential diagnoses are proposed:
Based on the patient’s age (70 years), clinical presentation (pathological fracture), and imaging showing a combination of bone thickening, mixed lytic and sclerotic changes, and marked cortical and trabecular thickening with deformities, the most likely diagnosis is:
Paget’s Disease of Bone (Osteitis Deformans)
If there is still doubt, additional tests such as serum alkaline phosphatase (ALP), tumor markers (e.g., PSA, CA15-3), or a local biopsy can help rule out metastatic tumors or other rare conditions.
Rehabilitation training should be individualized and progressive. Given increased bone fragility, it should be conducted cautiously after fracture healing or once fixation is stable.
During exercise, bone safety must be closely monitored. Should severe pain or joint swelling occur, promptly consult a physician to re-evaluate and adjust the training intensity.
FITT-VP Principle Example:
Continuous monitoring of the fracture healing process is necessary, along with regular follow-ups with orthopedic surgeons or rehabilitation specialists.
Disclaimer: This report provides a reference analysis and is not a substitute for an in-person consultation or professional medical advice. Specific treatment plans and rehabilitation strategies should be tailored to the patient’s condition under the guidance of qualified healthcare professionals.
Pagetic disease of the femur
