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ULY CLINIC
ULY CLINIC
22 Septemba 2025, 23:04:38
Comolli’s sign
Comolli’s sign refers to a triangular swelling over the scapula that matches its shape. This sign is a clinical indicator of scapular fracture, reflecting localized bony and soft tissue changes in the region following trauma.
Pathophysiology
The triangular swelling arises due to:
Displacement of scapular fragments: Fracture causes abnormal bone alignment, producing a triangular contour.
Localized soft tissue edema/hematoma: Trauma leads to inflammation and swelling around the scapula.
Muscle pull: Muscles attached to the scapula (supraspinatus, infraspinatus, subscapularis) may exacerbate deformity due to traction on fractured fragments.
Examination Technique
Inspection
Observe posterior thorax/scapular region for swelling, asymmetry, or deformity.
Note triangular or angular contour consistent with scapular outline.
Palpation
Elicit localized tenderness over scapula.
Detect irregular bony margins or crepitus on gentle palpation.
Functional Assessment
Assess for restricted shoulder movement or pain on abduction and rotation.
Clinical Features
Feature | Manifestation |
Pain | Localized scapular pain, worsens with movement |
Swelling/Deformity | Triangular swelling mirroring scapular shape |
Tenderness | Present over scapula, especially fracture line |
Functional impairment | Limited shoulder movement, pain with overhead or rotational activity |
Associated findings | Bruising, rib fractures, clavicular injury, or chest wall trauma |
Differential Diagnosis
Condition | Key Features | Notes |
Clavicular fracture | Swelling/deformity over clavicle, not scapula | More anterior, palpable step |
Rib fracture | Localized rib tenderness, pain with respiration | May coexist with scapular Fx |
Shoulder dislocation | Prominent acromion, loss of shoulder contour | Triangular scapular swelling absent |
Soft tissue contusion | Diffuse swelling, no bony tenderness or angular contour | Diagnosed by exclusion |
Pediatric considerations
Scapular fractures are rare in children, often associated with high-energy trauma (falls, vehicle accidents).
May be missed without imaging due to thick overlying musculature.
Geriatric considerations
Less common due to lower incidence of high-energy trauma, but when present, often associated with polytrauma.
Healing may be delayed due to osteoporosis or comorbid conditions.
Limitations
Comolli’s sign is not pathognomonic; soft tissue swelling may mimic triangular shape.
Requires radiologic confirmation (X-ray, CT scan).
May be masked in obese or heavily muscled individuals.
Patient counseling
Explain that the swelling suggests a possible scapular fracture.
Stress the importance of imaging studies to confirm diagnosis.
Reassure that most scapular fractures heal well with rest, immobilization, and physiotherapy, though surgery may be required in displaced fractures.
Advise monitoring for associated injuries (ribs, lungs, clavicle).
Conclusion
Comolli’s sign, characterized by triangular swelling over the scapula, is an important clinical clue for scapular fracture, often resulting from high-energy trauma. Though valuable in bedside assessment, it requires imaging confirmation and evaluation for associated thoracic injuries.
References
Rockwood CA, Matsen FA, Wirth MA, Lippitt SB. The Shoulder. 5th ed. Philadelphia: Elsevier; 2016.
Court-Brown CM, Heckman JD, McQueen MM, Ricci WM, Tornetta P. Rockwood and Green’s Fractures in Adults. 9th ed. Philadelphia: Wolters Kluwer; 2020.
Goss TP. Fractures of the scapula: diagnosis and treatment. J Am Acad Orthop Surg. 1995;3(1):22–33.
Ada JR, Miller ME. Scapular fractures: analysis of 113 cases. Clin Orthop Relat Res. 1991;(269):174–180.