H.T. Temple, MD Created March 2004; Revised December 2005
Pathologic Fractures H.T. Temple, MDCreated March 2004; Revised
December 2005 Pathologic Fractures Tumors Metabolic primary
secondary (metastatic) (most common) Metabolic osteoporosis (most
common) Pagets disease hyperparathyroidism Pathologic Fractures
Benign Tumors
Fractures more common in benign tumors (vs malignant tumors) most
asymptomatic prior to fracture antecedent nocturnal/rest symptoms
rare most common in children humerus femur unicameral bone cyst,
fibroxanthoma, fibrous dysplasia, eosinophilic granuloma Fractures
through benign tumors
Unicameral Bone Cyst Fractures observed more often in males than
females May be active or latent Almost always solitary First two
decades Humerus and femur most common sites Fracture through UBC
fallen fragmentsign (arrow) Unicameral Bone Cyst Treatment -
impending fractures
observation aspiration and injection methylprednisolone, bone
marrow or bone graft curetting and bone graft (+/-) internal
fixation Treatment - fractures allow fracture to heal and reassess
ORIF for femoral neck fractures Fibroxanthoma Most common benign
tumor Femur, distal tibia, humerus
Multiple in 8% of patients (associated with neurofibromatosis)
Increased risk of pathologic fracture in lesions >50% diameter
of bone and >22mm length Fibroxanthoma Treatment
observation
curetting and bone graft for impending fractures immobilization and
reassess after healing for patients with fracture Fibrous Dysplasia
Solitary vs. multifocal (solitary most common)
Femur and humerus First and second decades May be associated with
caf au lait spots and endocrinopathy (Albrights syndrome) Fibrous
Dysplasia Treatment observation
curetting and bone graft (cortical structural allograft) to prevent
deformity and fracture (+/-) internal fixation expect resorption of
graft and recurrence pharmacologicbisphosphonates Pathologic
Fractures through Primary Malignant Tumors
Relatively rare (often unsuspected) May occur prior to or during
treatment May occur later in patients with radiation osteonecrosis
(Ewings, lymphoma) Osteosarcoma, Ewings, malignant fibrous
histiocytoma, fibrosarcoma Pathologic Fractures Primary Malignant
Tumors
Suspect primary tumor in younger patients with aggressive appearing
lesions poorly defined margins (wide zone of transition) matrix
production periosteal reaction Patients usually have antecedent
pain before fracture, especially night pain Pathologic Fractures
Primary Malignant Tumors
Pathologic fracture complicates but does not mitigate against limb
salvage Local recurrence is higher Survival is not compromised
Patients with fractures and underlying suspicious lesions or
history should be referred for biopsy Pathologic fracture through
MFH arising in antecedent infarct
B Pathologic fracture through MFH arising in antecedent infarct
(H&E 100x) Pleomorphic spindled cells with storiform growth
pattern A Pathologic Fractures Primary Malignant Tumors
Always biopsy solitary destructive bone lesions even with a history
of primary carcinoma Case: A 62 year-old woman with a history of
breast carcinoma presented with a pathologic fracture through a
solitary proximal femoral lesion Intermediate grade
chondrosarcoma
Post- Pre-op Intermediate grade chondrosarcoma *fixation of primary
bone tumors is not done without other tumor treatment due to
potential for spread of tumor Pathologic Fractures Primary
Malignant Tumors
Treatment immobilization staging biopsy adjuvant treatment
(chemotherapy) resection/amputation Metabolic Bone Disease
Fractures through non-neoplastic bone disease Metabolic Bone
Disease Osteoporosis insufficiency fractures Pagets disease early
and late stages; most fractures occur in the late stage of disease
Hyperparathyroidism dissecting osteitis fractures through brown
tumors Pagets Disease Radiographic appearance Fracture
Treatment
Thickened cortices Purposeful trabeculae Bowing deformities Joint
arthrosis Fracture delayed healing malignant transformation
Treatment Osteotomy to correct alignment Excessive bleeding Joint
arthroplasty vs. ORIF Fracture through Pagetic bone (arrow) Mixed
radiodense and radiolucent lesions
Hyperparathyroidism Adenoma Polyostotic disease Mental status
changes Abdominal pain Nephrolithiasis mixed radiolucent/radiodense
Mixed radiodense and radiolucent lesions Multiple brown tumors in a
patient with primary hyperparathyroidism Hyperparathyroidism May be
secondary to renal failure Treatment
tertiary Treatment parathyroid adenectomy ORIF for fracture correct
calcium Pathologic fracture through brown tumor (arrow) Fractures
in Patients with Metastatic Disease and Myeloma
Aside from osteoporosis, most common causes of pathologic fracture
Fifth decade and beyond Appendicular sites: femur and humerus most
common All metastatic tumors are not treated the same Overall
Incidence of Metastases to Bone at Autopsy
70%Jaffe, 1958 12%Clain, 1965 32%Johnson, 1970 21%Dominok, 1982
Incidence of Metastases at Autopsy by Primary Tumor Site
Primary Site % metastasis to Bone Breast Lung Prostate Hodgkins
Kidney Thyroid Melanoma Bladder Incidence of Metastases
60% of patients with early identified cancer may already have
metastases 10-15% of all patients with primary carcinoma will have
radiologic evidence of bone metastases during course of disease
Route of Metastases Contiguous Hematogenous most common
Destructive lesions in bone from lung carcinoma (arrows) Mechanism
of Metastases
Release of cells from the primary tumor Invasion of efferent
lymphatic or vascular channels Dissemination of cells Endothelial
attachment and invasion at distant site Angiogenesis and tumor
growth at distant site Metastatic carcinoma In body pedicle
junction Bone Destruction Early Late most important osteoclast
mediated
(RANK L) Late malignant cells may be directly responsible
Metastases of Unknown Origin
3-4% of all carcinomas have no known primary site 10-15% of these
patients have bone metastases Diagnostic Strategy for Patients with
Unknown Primary
% Primary Tumor Identified History and Physical8% Chest X-Ray43%
Chest CT % Abdominal CT13% Biopsy8% Rougraff, 1993 Defects Cortical
defects weaken bone especially in torsion Two types
stress riser - smaller than the diameter of bone open section
defect - larger than the diameter of bone. causes a 90% reduction
in load to failure and demand augmentation and fixation Impending
Pathologic Fracture
61% of all pathologic fractures occur in the femur 80% are
peritrochanteric fracture in this area results in significant
morbidity historic data on impending pathologic fracture involves
the proximal femur Impending Pathologic Fracture
Parrish and Murray, 1970 increasing pain with advancing cortical
destruction of lesions involving >50% of the shaft diameter
Beals, 1971 lesions >2.5 cm are at increased risk to fracture
Murray, 1974 increased fracture with destruction of > one-third
of the cortex, pain after radiotherapy Impending Pathologic
Fracture
Fidler, 1981 % shaft destroyed Incidence Fx (%) 0-25%0% 25-50%3.7%
50-75%61% >75%79% Conclusion: Patients with tumors destroying
>50% of the diameter of bone require prophylactic internal
fixation Indication for Prophylactic Internal Fixation
Harrington criteria >50% of diameter of bone >2.5 cm pain
after radiation fracture of the lesser trochanter Limitations only
for proximal femur doesnt account for tumor biology Harrington,
K.D.: Clin. Orthop. 192: 222, 1985 Mirels Scoring System Score 1 2
3
Siteupper limblower limbperitrochanteric Pain
mildmoderatefunctional Lesionblastic mixed lytic Size2/3 Based on a
retrospective study of 78 pts with metastatic disease to long
bones.27 patients fractured within 6 months.Their mean Mirels score
was 10 while those without fracture had a score of < 7. Score
< 7 no surgery Score > 7 prophylactic fixation Mirels,
H.:Clin. Orthop.249: 256, Radiotherapy All tumor defects that meet
the criteria for internal fixation do not require surgery >50%
of diameter of bone >2.5 cm pain after radiation fracture of the
lesser trochanter Tumor biology is variable - some lesions are very
sensitive to radiotherapy Radiotherapy Pre XRT Prostate CA Post XRT
Prostate CA Goals of Surgery in Treating Patients with Pathologic
Fractures
Relieve pain Restore function Facilitate nursing care Pathologic
Fracture Survival
75% of patients with a pathologic fracture will be alive after one
year the average survival is ~ 21 months Pathologic Fracture
Treatment
Biopsy especially for solitary lesions Nails versus plates versus
arthroplasty plates, screws and cement superior for torsional loads
interlocked nails stabilize entire bone Cement augmentation
Radiation/chemotherapy Aggressive rehabilitation Renal Cell
Carcinoma pre-op pre-op post-op
*pre operative embolization of renal cell mets should be done
Pathologic Fracture Treatment
Periarticular fractures, especially around the hip are more
appropriately treated with arthroplasty Periacetabular fractures
protrusio shell, cement, arthroplasty saddle prosthesis Structural
allograft-prosthesis composite Fracture Healing 129 patients
overall rate = 35%
74% for patients surviving > 6 months radiotherapy