Ultrasound Assessment of Muscle Injury Associated with Closed Limb Fracture

Table 1

Ultrasound classification criteria for muscle injury.

Type	score
(A) Muscle fibre
Grade I:	1
No abnormalities, with/without focal fibre rupture with less than 5% of the muscle involved
Grade II:	3
Partial rupture: focal fibre rupture with more than 5% but less than 30% of the muscle involved with/without fascial damage
Grade III:
Focal fibre rupture with more than 30% to complete muscle rupture with retraction, fascial damage	5
(B) Complication of muscle rupture: muscle haematoma
Grade I:
No haematoma or small haematoma (total diameter <10 mm)	1
Grade II:
1–2 haematomas (total diameter: 10–30 mm)	2
Grade III:
3 or more haematomas (total diameter: >30mm), or a honeycombed pattern	3
(C) Main vascular injury
Grade I:
No abnormalities on vascular ultrasonography	1
Grade II:
Decreased arterial diameter and blood flow, partial arterial or venous rupture, partial arterial thrombosis	2
Grade III:
Complete arterial rupture, complete arterial thrombosis and no blood flow in the distal muscle	3
(D) Diameter growth rate of the muscle (scored in the maximum number)
Grade I:  Growth rate <10%	1
Grade II:   Growth rate 10%–50%	2
Grade III:  Growth rate >50%	3
Total score	14