The case

An adventurous middle schooler jumped off a picnic table because he wanted to film something cool for his YouTube channel. His lifelong dream is to become a YouTuber. His current dream is to have an arm that is more straight. He was taken to the Emergency Department and he got some X-Rays.

From – Biology of fracture healing – an overview –

The diagnosis

This is a both bone forearm fracture – you know a BBFF. Specifically his X-Ray shows closed mid-diaphysial, comminuted and angulated fractures of the left radius and ulna.


In terms of your initial assessment your main goals are to assess for neurologic and vascular compromise. Fortunately significant injuries to nerves or vessels are infrequent in the forearm fracture. You should assess the following:

  • Color of the distal extremity
  • Capillary refill
  • Radial pulse & Ulnar pulse (usually harder to palpate)
  • Sensation of radial, median and ulnar nerves (see sensory map below)
  • Motor function – I ask the patient to do the following
    • Make a fist
    • Extend all fingers
    • Thumbs up
    • Opposed thumb to pinky finger
    • Vulcan salute for bonus points

    • From

Certainly this is a fracture that will benefit from closed reduction. In general there are are recommendations from orthopedics as to how angulated a fracture may be to avoid reduction. Note that angulation can be assessed on both the anterior-posterior and lateral views of the radius/ulna X-Ray.

Under 5 years

  • Lateral   10 to 35 degrees
  • AP   10 degrees

5 to 10 years

  • Lateral   10 to 25 degrees
  • AP   10 degrees

Older than 10 years

  • Lateral   5 to 20 degrees
  • AP   0 degrees

These ranges are pretty wide. The younger the kid, the greater the tolerable angulation. If those ranges put you off a quick rule of thumb (limb?) is to discuss any fracture >10-15 degrees with ortho if you are unsure whether or not reduction is warranted. Reduction is best performed within 3 to 5 days. Many children will of course benefit from procedural sedation. Obviously any limb with vascular compromise needs at least partial reduction to preserve distal circulation.

Given that are doctors any good at estimating fracture angle? The answer, at least per Gaskin et al is that we are not so good. Their study revealed that trauma and orthopedic surgeons had poor inter-rater agreement and had a mean error of 8-9 degrees.


  • Gaskin JS, Pimple MK, Wharton R, Fernandez C, Gaskin D, Ricketts DM. How accurate and reliable are doctors in estimating fracture angulation? Injury. 2007;38(2):160. Epub 2006 Dec 1.
  • Price CT, Flynn JM. Management of fractures. In: Lovell and Winter’s Pediatric Orthopaedics, 6th ed, Morrissey RT, Weinstein SL (Eds), Lippincott, Philadelphia 2006. p.1463.
  • Waters PM, Bae DS. Fractures of the distal radius and ulna. In: Rockwood and Wilkin’s Fractures in Children, 7th ed, Beaty JH, Kasser JR (Eds), Lippincott Williams & Wilkins, Philadelphia 2010. p.292.