The case
A young man jumps from the cough. he anticipated that he would land smoothly, and stably like his cat Whiskers. He did not land smoothly. Instead he careened off of the coffee table and awkwardly landed on his outstretched arm. He told his mom, and Whiskers. Mom was concerned because he now has a swollen and painful wrist. Whiskers, as is apropos his species could care less. Fearing that his arm was broken, or worse fractured mom promptly took her son to the ED. Whiskers stayed behind.
In the ED the young daredevil’s examination revealed a tender, somewhat swollen distal forearm. Examination of the distal extremity revealed no neuromuscular deficits. An X-Ray was obtained.
Case courtesy of Dr Maulik S Patel, Radiopaedia.org. From the case rID: 19730
The Diagnosis
This is a buckle fracture – AKA torus fracture of the distal radius. Note the circled area in the following picture which demonstrates the abnormality. Normally there is a very smooth curvature of the cortical surface as the cortex approaches the physis.
Discussion
Buckle fractures are incomplete long bone fractures seen commonly in children. You will note the characteristic bulging of the cortical surface. this happens when the child lands on an outstretched hand, and the bone is compressed via an axial load. You will most often see them in the distal forearm (radius >ulna) but they can be seen in other long bones as well. these are typically stable fractures that will present with minimal to mild angulation. Immobilization with a splint (volar, radial gutter or sugar tong are acceptable), cast or even rigid removable brace is appropriate. Patients are most often immobilized for only 2-4 weeks. One study showed an increased rate of pain in solar fiberglass splints vs casting. Need for reduction is rare; surgical intervention even rarer. Providers in the Emergency Department need not consult Orthopedics for this type of fracture.
Interestingly, the term “torus” fracture could be most accurately used to describe a circumferential buckle fracture. However, using buckle = torus synonymously is OK as well. The name torus comes from the round structure at the base of an architectural column. There is no plinth fracture.
