Pathologic Fractures Flashcards
pathologic fracture definition
occurs when normal integrity and strength of bone have been compromised by invasive or destructive processes
causes of pathologic fractures (7)
neoplasm, necrosis, metabolic disease, disuse, infection, osteoporosis, iatrogenic
are fractures more common in benign or malignant tumors?
benign
most common locations of pathologic fractures secondary to benign tumors in children (2)
humerus, femur
most common benign tumors associated with pathologic fractures in children (4)
unicameral bone cyst, non-ossifying fibroma, fibrous dysplasia, eosinophilic granuloma
primary malignant tumors associated with pathologic fractures (6)
osteosarcoma, ewing sarcoma, chondrosarcoma, malignant fibrous histiocytoma, fibrosarcoma, etc
suspect a primary tumor in younger patients with aggressive-appearing lesions (3 characteristics)
poorly defined margins (wide zone of transition), matrix production, periosteal reaction
do benign or malignant tumors have antecedent pain before fracture
more often malignant
mechanism of injury in pathologic fractures
may be result of minimal trauma or normal activity
clinical history eliciting suspicion for pathologic fracture (5)
normal activity or minimal trauma, excessive pain at the site of fracture prior to injury, patients with known primary malignant disease or metabolic disease, history of multiple fractures, risk factors (smoking/environmental exposure to carcinogens)
additional physical exam (3)
adjacent peripheral lymph nodes, check for masses, other painful areas for impending fractures
laboratory evaluation (8)
cbc w diff, red blood cell indices, and peripheral smear; esr; chem panel; ua; stool guaiac; spep/upep; 24-hr urine hydroxyproline; specific tests
most specific laboratory tests for suspected pathologic fracture (4)
thyroid function tests, carcinoembryonic antigen, parathyroid hormone, prostate-specific antigen
abnormal lab finding in osteoporosis
none
abnormal lab finding(s) in osteomalacia
low urine calcium
abnormal lab finding(s) in hyperparathyroidism (1+/-2)
high urine calcium +/- high serum calcium/low serum phosphorus
abnormal lab finding(s) in renal osteodystrophy (3)
low serum calcium, high serum phosphorus, high serum alkaline phosphatase
abnormal lab finding(s) in paget disease (2)
very high serum alkaline phosphatase, urine hydroxyproline
abnormal lab finding(s) in myeloma (1)
urine protein (spep/upep) bence-jones proteins
percent bone loss detectable by standard x-ray
> 30%
radiographs evaluating for pathologic fractures (5)
chest radiograph, bone scan, ct, mri, pet scan
prevalence of paget disease in the elderly population
5% to 15%
primary malignant tumors metastasizing to bone
blt kosher pickle (breast, lung, thyroid, kidney, prostate)
most common locations of pathologic fractures associated with metastatic disease (5)
spine, ribs, pelvis, femur, humerus
basis of springfield classification of pathologic fractures
pattern of bone invasion (systemic vs localized)
correctable disorders associated with pathologic fractures (5)
osteomalacia, disuse osteoporosis, hyperparathyroidism, renal osteodystrophy, steroid-induced osteoporosis
initial treatment of pathologic fracture (3)
standard fracture care, evaluation of underlying pathologic process, optimization of medical condition
goals of operative management of pathologic fracture (4)
prevention of disuse osteopenia, mechanical support for weakened or fractured bone to permit the patient to perform daily activities, pain relief, decreased length and cost of hospitalization
standard of care for most pathologic fractures
internal fixation with or without cement augmentation
what may be considered for impending pathologic fractures in periarticular locations or for failed attempts of internal fixation
resection and prosthetic reconstruction
most common complication in treatment of pathologic fractures
loss of fixation
contraindications to surgical management of pathologic fractures (3)
medical clearance, mental obtundation precluding need for pain relief (srsly?), life expectancy <1 month (controversial)
what percentage of pathologic fracture patients will be alive after 1 year
75%
average survival time for pathologic fractures (obviously varies by primary diagnosis)
~21 months
solitary lesions with pathologic fractures require ______
biopsy
role of radiation and chemotherapy in treatment of pathologic fractures (3)
palliate symptoms, diminish lesion size, prevent advancement of lesion
treatment of pathologic femoral neck fracture in the absence of acetabular involvement
hemiarthroplasty
treatment of pathologic femoral shaft fractures
intramedullary nailing
indications for prophylactic fixation (Harrington) (4)
cortical bone destruction >50%, proximal femoral lesion >2.5cm, pathologic avulsion of the lesser trochanter, persistent pain following irradiation
Mirel’s score cutoff for prophylactic internal fixation
8
treatment of painful pathologic spine fracture, but no neurologic loss, or loss of height
radiation therapy
treatment of pathologic spine fractures caused by osteoporosis, myeloma, metastatic carcinoma
percutaneous cement placement in the vertebral body
concern with percutaneous cement placement in vertebral body for pathologic spine fractures
leakage into canal and adjacent veins
treatment of pathologic spine fracture with neurological loss
spinal decompression and fusion with internal fixation anteriorly or posteriorly
