What is the next step in managing a patient with swelling over the right sternocleidomastoid, focal tenderness, and bony irregularity on ultrasound?

Management of Bony Irregularity at Cervical Transverse Process

The next step is to obtain dedicated cervical spine imaging with CT scan to definitively characterize the bony irregularity and exclude fracture, followed by clinical correlation to determine if this represents a stress injury, degenerative change, or other osseous pathology.

Rationale for Advanced Imaging

The ultrasound findings of focal tenderness with bony irregularity at the cervical transverse process require further characterization, as ultrasound has significant limitations in evaluating osseous structures beyond the cortical surface.

• Ultrasound can detect cortical bone irregularity, periosteal thickening, and subcutaneous edema, but cannot evaluate subcortical or trabecular bone pathology 1
• While ultrasound identifies bony lesions including erosions, changes in bone profile, and osteophytes, it is operator-dependent and limited to superficial cortical assessment 1
• CT is superior to ultrasound for characterizing bony abnormalities, with specificity ranging from 88% to 98% for osseous injuries 1

Recommended Imaging Algorithm

First-Line: CT Cervical Spine Without Contrast

• CT should be obtained when ultrasound findings are equivocal or show bony irregularity requiring definitive characterization 1
• CT provides detailed visualization of cortical and trabecular bone architecture that ultrasound cannot assess 1
• This modality will differentiate between fracture (acute or healing), degenerative changes, osseous proliferation, or other pathology 1

Alternative Consideration: MRI Cervical Spine

• MRI is extremely sensitive for detecting stress reactions, bone marrow edema, and soft tissue abnormalities that may accompany bony irregularity 1
• Fluid-sensitive sequences can identify stress reactions or muscle/tendon injuries even when no discrete fracture line is present 1
• MRI provides both diagnostic and prognostic information for osseous stress injuries 1
• Consider MRI if CT is negative but clinical suspicion remains high, or if soft tissue pathology (ligamentous injury, nerve impingement) is suspected 1

Clinical Correlation Points to Assess

History Elements

• Mechanism of injury or repetitive activity pattern - stress fractures develop with new or repetitive athletic activity 1
• Duration and progression of symptoms
• Presence of neurological symptoms suggesting nerve root involvement
• History of trauma, even minor

Physical Examination Findings

• Focal point tenderness over the transverse process - already documented on ultrasound examination
• Range of motion limitations
• Neurological examination including motor, sensory, and reflex testing
• Palpation for step-off deformity or abnormal prominence

Differential Diagnosis to Consider

Based on the bony irregularity finding:

• Stress fracture or insufficiency fracture of the transverse process 1
• Acute traumatic fracture (healing or acute)
• Degenerative changes with osteophyte formation 1
• Osseous proliferation from chronic stress or inflammation
• Less likely: infection, neoplasm (would typically have additional imaging findings)

Common Pitfalls to Avoid

• Do not rely solely on ultrasound for definitive diagnosis of bony pathology - ultrasound cannot evaluate subcortical bone and trabecular stress fractures may be missed 1
• Do not assume degenerative changes without advanced imaging - bony irregularity in a symptomatic patient warrants definitive characterization to exclude fracture 1
• Do not delay imaging if neurological symptoms are present - transverse process pathology can be associated with nerve root involvement requiring urgent evaluation
• Avoid confusing periosteal reaction visible on ultrasound with soft tissue pathology - periosteal thickening and cortical irregularity indicate underlying osseous pathology requiring CT or MRI 1

Management After Imaging

Once the nature of the bony irregularity is characterized:

• If fracture is confirmed: Conservative management with activity modification, analgesia, and follow-up imaging to ensure healing
• If degenerative changes: Symptomatic treatment with physical therapy, NSAIDs if not contraindicated, and activity modification
• If stress reaction without fracture: Activity modification and close follow-up with repeat imaging if symptoms persist 1
• If concerning for infection or neoplasm: Biopsy or additional staging studies as indicated