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