g17 pathologic fxs
TRANSCRIPT
Pathologic Fractures
H.T. Temple, MD
Pathologic Fractures
• Tumors– primary– secondary (metastatic) (most common)
• Metabolic– osteoporosis (most common)– Paget’s disease– hyperparathyroidism
Pathologic Fractures Benign Tumors
• Fractures more common in benign tumors (vs malignant tumors)– most asymptomatic prior to fracture– antecedent nocturnal symptoms rare– most common in children
• humerus• femur
– unicameral bone cyst, fibroxanthoma, fibrous dysplasia, eosinophilic granuloma
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
Unicameral Bone Cyst
• Treatment - impending fractures– observation – aspiration and injection methylprednisolone or
bone graft material– 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
(especially patients 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
café au lait spots and endocrinopathy (Albright’s syndrome)
Fibrous Dysplasia
• Treatment– observation– curetting and bone graft (cortical allograft) to
prevent deformity and fracture (+/-) internal fixation
– expect resorption of graft and recurrence– pharmacologic—bisphosphonates
Pathologic FracturesPrimary Malignant Tumors
• Relatively rare• May occur prior to or during treatment• May occur later in patients with radiation
osteonecrosis (Ewing’s, lymphoma)• Osteosarcoma, Ewing’s, malignant fibrous
histiocytoma, fibrosarcoma
Pathologic FracturesPrimary 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 FracturesPrimary 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
A
B
A. Pathologic fracture through MFHarising in antecedent infarct
B. (H&E 100x) Pleomorphic spindledcells with storiform growth pattern
Pathologic FracturesPrimary 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
Pre-op Post-
Intermediate grade chondrosarcoma
*fixation of primary bone tumors is not done without other tumor treatment due to potential for spread of tumor
Pathologic FracturesPrimary Malignant Tumors
• Treatment– immobilization– staging– biopsy– adjuvant treatment (chemotherapy)– resection/amputation
Metabolic Bone Disease
• Osteoporosis– insufficiency fractures
• Paget’s disease– early and late stages; most fractures occur in the
late stage of disease• Hyperparathyroidism
– dissecting osteitis– fractures through brown tumors
Paget’s Disease• Radiographic appearance
– Thickened cortices– Purposeful trabeculae– Bowing deformities– Joint arthrosis
• Fracture – delayed healing– malignant transformation
• Treatment– Osteotomy to correct alignment– Excessive bleeding– Joint arthroplasty vs. ORIF
Hyperparathyroidism
• Adenoma• Polyostotic disease• Mental status changes• Abdominal pain• Nephrolithiasis• Polyostotic disease
– mixed radiolucent/radiodense
Mixedradiodense
andradiolucent
lesions
Hyperparathyroidism
• May be secondary to renal failure
– secondary– tertiary
• Treatment – parathyroid adenectomy– ORIF for fracture– correct calcium Pathologic fracture
through brown tumor
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 BoneBreast 50-85Lung 30-50Prostate 50-70Hodgkin’s 50-70Kidney 30-50Thyroid 40Melanoma 30-40Bladder 12-25
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
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
Bone Destruction
• Early– most important– osteoclast mediated
• 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 Physical 8%Chest X-Ray 43%Chest CT 15%Abdominal CT 13%Biopsy 8%
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– doesn’t account for tumor biology
Harrington, K.D.: Clin. Orthop. 192: 222, 1985
Mirels Scoring System
Score 1 2 3
Site upper limb lower limb peritrochanteric
Pain mild moderate functional
Lesion blastic mixed lytic
Size <1/3 1/3-2/3 >2/3
Score < 7 – no surgeryScore > 7 – prophylactic fixation
Mirels, H.: Clin. Orthop. 249: 256, 1989.
AA
BB
A.A. Impending pathologic Impending pathologicfracture femoral neckfracture femoral neck
B.B. Quantitative CT Quantitative CT
AA
Quantitative CT is a more sensitive study to assess the degree Quantitative CT is a more sensitive study to assess the degree of bone destructionof bone destruction
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
RadiotherapyPre XRTProstate
CA
Post XRTProstate
CA
Goals of Surgery in Treating Patients with Pathologic Fractures
• Relieve pain• Restore function• Facilitate nursing care
Pathologic FractureSurvival
• 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
pre-op pre-op post-op
Renal Cell Carcinoma
*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 <30 GY did not adversely
affect fracture healing
Gainor, B.J.: CORR 178: 297, 1983
Cement
PMMA no PMMAPain relief 97% 83%
Ambulation 95% 75%
Fixation failure 2 cases 6 cases
Haberman, E.T: CORR, 169: 70, 1982
Pre-opPre-oprenal cellrenal cellcarcinomacarcinoma
Post-oprenal cellcarcinoma
Resection for Pathologic and Impending Pathologic Fractures
• Radiation and chemotherapy resistant tumors– renal– thyroid– melanoma– occasionally lung
• Solitary metastases (controversial)
Solitary adenocarcinoma
• Post-op intercalary allograft
Complications
• Infection– malnutrition– hematomyelopoetic suppression
• Hemorrhage– vascular tumors ( renal and thyroid)
• Tumor recurrence• Failure of fixation• Thromboembolic disease
Post embolizationPre embolization
Pre-operative embolization can preventhemorrhage with intra-lesional surgery
Summary
• Diagnosis and treatment requires a multidisciplinary approach
• Aggressive surgical treatment relieves pain, restores function, and facilitates nursing care
• Biopsy all solitary lesions or refer appropriately• Understand tumor biology and tailor treatment
Thank You
Return to General Index