Rib fracture is the most common chest wall injury, typically resulting from blunt trauma. It can occur in all age groups but may develop with minimal trauma in osteoporotic elderly patients. The 4th-9th ribs are most commonly affected. Acute fractures are characterized by cortical disruption and displacement; callus formation develops during healing. Stress fractures result from repetitive mechanical loading and are seen in athletes (especially 1st rib in rowers), chronic cough patients. Pathologic fractures develop with minimal trauma in the setting of underlying bone lesions (metastasis, myeloma, fibrous dysplasia). Complications include pneumothorax, hemothorax, pulmonary contusion, great vessel injury (1st-2nd rib fractures), splenic/hepatic injury (lower rib fractures), and flail chest (3+ consecutive ribs fractured in two lines). Diagnosis is confirmed by CT; bone scintigraphy is sensitive for occult fractures.
Age Range
20-90
Peak Age
55
Gender
Male predominant
Prevalence
Common
Rib fractures occur when force applied to bone exceeds its elastic deformation capacity. In traumatic fractures, high-energy external force breaks the bone cortex — most commonly in the posterolateral region where rib curvature is most prominent. In stress fractures, repetitive submaximal forces (coughing, rowing, heavy exercise) lead to microfracture accumulation — when normal bone remodeling capacity is exceeded, macroscopic fracture develops. In pathologic fractures, the underlying lesion (metastasis, myeloma, fibrous dysplasia) has disrupted normal bone structure and reduced mechanical strength. The pathophysiological basis of imaging findings: cortical disruption on CT appears as a low-attenuation line cutting through the mineral structure of bone — cortical integrity is lost. In the acute phase, hemorrhage and edema around the fracture line manifest as periosteal reaction. During healing (2-6 weeks), fibroblast and osteoblast proliferation forms callus — initially radiolucent (fibrous callus), then radiopaque (bony callus). On bone scintigraphy, increased osteoblastic activity at the fracture site causes intense Tc-99m MDP uptake — becomes positive 24-72 hours post-fracture and persists for 6-12 months.
Low-attenuation linear defect demonstrating loss of cortical continuity on CT bone window — direct evidence of fracture. Optimal evaluation is achieved with thin-section (1 mm) and MPR.
On thin-section CT (bone window, 1-1.5 mm), a low-attenuation linear defect demonstrating cortical disruption of the rib is seen. The fracture line may be complete (entire cortex fractured) or incomplete (greenstick — one cortex intact). In displaced fractures, bone fragments are displaced relative to each other. Multiple fractures require individual rib assessment, and flail chest (3+ consecutive ribs fractured in two lines) should be evaluated. Associated pneumothorax, hemothorax, and pulmonary contusion findings should be noted.
Report Sentence
An acute fracture line demonstrating cortical disruption with ___ mm displacement is seen in the ___ rib.
In healing fractures (2-6 weeks post-injury), periosteal and endosteal callus formation is seen around the fracture line. In early stages, callus is low-attenuation (fibrous callus — unmineralized osteoid), in late stages high-attenuation (bony callus — mineralized bone). Callus bridges the fracture line and expands the outer contour of bone. In advanced stages, the fracture line becomes obscured and remodeling begins. Malposition (angulation, shortening) and pseudoarthrosis (nonunion) should be evaluated.
Report Sentence
Periosteal callus formation consistent with healing phase is seen in the ___ rib, with partial bridging of the fracture line.
On bone scintigraphy (Tc-99m MDP), focal intense radiopharmaceutical uptake is seen at the fracture site. Acute fractures become positive 24-72 hours post-trauma (>95% sensitivity — even in CT-negative occult fractures). Uptake persists for 6-12 months and decreases with healing. Multiple fractures are frequently seen as intense uptake areas in a linear pattern (consecutive ribs). Stress fractures typically show fusiform-shaped focal uptake. In pathologic fractures, uptake pattern may be irregular and overlap with the underlying lesion uptake.
Report Sentence
Focal intense Tc-99m MDP uptake is seen in the ___ rib on bone scintigraphy, consistent with acute/subacute fracture.
Complications of rib fractures should be assessed on CT. Pneumothorax: air in pleural space (anterior in supine, apical in erect position); hemothorax: fluid-density collection in pleural space (30-70 HU, higher than simple effusion); pulmonary contusion: ground-glass/consolidation areas adjacent to fracture site; subcutaneous emphysema: air in chest wall soft tissues. Upper rib fractures (1st-2nd) indicate high-energy trauma and great vessel/brachial plexus injury should be investigated. Lower rib fractures (9th-12th) should be correlated with splenic (left) and hepatic (right) injury.
Report Sentence
Findings of ___ (pneumothorax/hemothorax/pulmonary contusion) accompanying the rib fractures are seen.
On STIR sequence, markedly hyperintense bone marrow edema is seen at the fracture site. The fracture line may be visualized as a hypointense line on T1. MRI can be used as an alternative to bone scintigraphy for detecting occult fractures (CT-negative, clinically suspected) — particularly sensitive for stress fractures. Accompanying soft tissue edema and hematoma are also assessed. In pathologic fractures, the underlying bone marrow lesion (metastasis, myeloma) can be identified by MRI.
Report Sentence
Markedly hyperintense bone marrow edema corresponding to the fracture site is seen in the ___ rib on STIR sequence.
Stress fractures develop from repetitive mechanical loading and appear on CT as incomplete cortical break (one cortex fractured, opposite cortex intact) with mild periosteal thickening/callus. Most commonly affected are 1st rib (rowers, heavy lifters), 4th-8th ribs (chronic cough, golf, rowing) and posterolateral region. The fracture line may be thin and non-displaced — can be missed on standard CT slice thickness, thin-section (1 mm) and MPR are required. May be initially negative on radiography, becoming visible with callus after 2-3 weeks.
Report Sentence
Incomplete cortical break with periosteal thickening in the posterolateral region of the ___ rib is seen, consistent with stress fracture.
Criteria
Cortical disruption following blunt or penetrating trauma, usually 4th-9th ribs, posterolateral region
Distinct Features
Sharp fracture line, bone marrow edema, accompanying soft tissue injury; displacement and complications (pneumothorax, hemothorax) are assessed
Criteria
Incomplete fracture from repetitive mechanical loading (coughing, sports, heavy work); without trauma history
Distinct Features
Incomplete cortical break, periosteal reaction, non-displaced; 1st rib (athletes), 4th-8th ribs (cough); may be missed on CT, MRI or scintigraphy are sensitive
Criteria
Fracture developing with minimal trauma in the setting of underlying bone lesion; metastasis, myeloma, fibrous dysplasia, Paget
Distinct Features
Lytic/blastic lesion accompanying fracture line, soft tissue mass, periosteal destruction; disproportionate fracture with minimal trauma; underlying lesion requires MRI evaluation
Criteria
2-12 weeks post-fracture, callus formation and bridging of fracture line process
Distinct Features
Periosteal/endosteal callus, obscuration of fracture line, bone contour expansion; mineralization degree reflects healing stage; malposition and pseudoarthrosis should be evaluated
Distinguishing Feature
Metastasis: lytic/blastic bone destruction, soft tissue mass, periosteal reaction, known primary malignancy; fracture: clean fracture line, no underlying lesion, trauma history
Distinguishing Feature
Fibrous dysplasia: ground-glass matrix, rib expansion, well-defined; fracture: cortical disruption, displacement, callus; however, pathologic fracture can develop within fibrous dysplasia
Distinguishing Feature
Osteomyelitis: bone marrow edema + soft tissue abscess/cellulitis, periosteal reaction, fever/leukocytosis; fracture: cortical disruption, trauma/mechanical loading history, periosteal reaction callus-type
Distinguishing Feature
Ewing sarcoma: aggressive periosteal reaction (onion skin), permeative bone destruction, large soft tissue mass, pediatric/young age; fracture: clean cortical disruption, non-aggressive periosteal reaction, all age groups
Urgency
urgentManagement
conservativeBiopsy
Not NeededFollow-up
6-monthIsolated rib fractures are generally managed conservatively (analgesia, breathing exercises, activity restriction). However, complications (pneumothorax, hemothorax, flail chest) require emergent intervention — chest tube, surgical stabilization. Elderly patients and those with multiple fractures have increased risk of pneumonia and respiratory failure. When pathologic fracture is suspected, investigation of the underlying lesion (MRI, biopsy, PET-CT) is required. Stress fractures heal with activity modification and rest (4-6 weeks). Follow-up: clinical monitoring is sufficient for uncomplicated fractures; CT control is recommended when healing delay or pseudoarthrosis is suspected.
Rib fractures usually heal with conservative treatment (analgesia, respiratory physiotherapy). Multiple fractures (≥3 consecutive) carry flail chest risk and may require mechanical ventilation. Lower rib fractures (9-12) should prompt evaluation for liver and spleen injury. Elderly patients are at high risk for pneumonia and atelectasis complications. Underlying lesion should be investigated if pathologic fracture is suspected.