Fractures of the forearm are very common orthopedic injuries in children.
A both bone forearm fracture (BBFF) is unique in that it involves both the ulna and radius (the two bones in the forearm).
A BBFF is an unstable break that generally occurs in the middle of both bones - usually after a Fall Onto an Outstretched Hand (FOOSH) but, occasionally, from a direct blow to the arm.
These fracture patterns vary in severity, and clinical presentation, but children who sustain badly displaced BBFF's present with an obvious forearm deformity and severe pain.
If you are worried about a possible forearm fracture, remain calm and consider doing the following for your child:
1. Splint the injured extremity immediately: brace it loosely to a rigid cardboard or plastic splint or whatever material is available to limit excessive movement of the suspected broken bone. A splint or brace should not be applied too tightly. When applied correctly, it will diminish and limit the symptoms of pain when transporting the child to ones nearest medical facility.
2. See a doctor urgently to assess and x-ray the injury. The doctor will establish a diagnosis, identify complications and ensure appropriate treatment.
The radius is the long bone on the thumb side of the forearm, and the ulna is the long bone on the pinky side of the forearm.
Credit @ OrthoInfo, American Academy of Orthopaedic Surgeons
What is so unique about fractures of the forearm in children?
Because children are still growing, their bones are capable of compensating for residual misalignment after a fracture. This physiological potential confers good tolerance to a certain degree more of bony angulation and displacement than that which would be permitted in adults.
This ability to heal with few complications despite some residual misalignment is called “remodeling”, and is unique to paediatric fractures.
It is for this reason, BBFFs often do well without aggressive surgical management. At the time the fracture has healed, despite slight residual displacement, children seldom have long-term, significant loss of function thanks to their remodeling potential.
What are the treatment options for my child?
Most both bone fractures can be treated without surgery – often only requiring Manipulation Under Anaesthetic (MUA) to improve alignment, and application of a cast around the upper limb to maintain the corrected position.
MUA and casting is considered first-line therapy, and is the Gold Standard of treatment for BBFFs.
A cast is applied between three to six weeks and will often extend below the wrist and above the elbow to provide stability and limit rotation of the fracture.
Despite MUA and casting being the favoured treatment option, there are certain occasions when Dr. Maina would strongly recommend parents consider surgery with the use of implants for their children's BBFFs. These are discussed below:
- Loss of reduction in a cast is recognized as the commonest complication of MUA and casting. Over time, after discharge home, fractures may lose alignment either as the swelling around the fracture subsides or because there was limited pressure applied around the fracture. In these instances, casting is deemed to have ‘failed’. Surgery through remanipulation and the use of implants may then be used to restore and maintain alignment.
- A severe fracture pattern may preclude a successful MUA. Rather than manipulate excessively, to get the best outcome, surgery may then be performed at that initial Operating Room (OR) visit, as the next best option to gain and maintain alignment and stability.
- A BBFF can recur after a second, accidental FOOSH. This is most likely to happen within six months of the initial injury - despite the fracture having healed. These recurrent fractures need surgery. Implants potentially limit the need for prolonged immobilization and may provide added stability as they are often only removed well after fracture union.
- Badly contaminated open fractures do not do well with closed casting. To enable easy access and wound care, circumferential casts are avoided in these injuries and implants are relied upon for fracture stabilization.
What types of implants are used in BBFFs?
Prosthetics used for bony stability include - but are not limited to - TENS nails (Titanium Elastic Nail System), Rush nails, K-wires (Kirschner wires), plates and screws as well as external fixators in severe trauma. Their use is dictated by the location and type of fracture as well as your surgeon's preference. Some of will be discussed below.
TENS are thin, bendable nails inserted through small incisions at the elbow and/or wrist. TENS nails sit in the bone canal, maintaining alignment. Because these implants are designed to enter the bone far from the fracture, well-executed TENS nailing curbs the severity of trauma at the fracture site, as the fracture site is seldom opened. TENS nails are a popular option among orthopaedic surgeons due to the limited surgical incisions required, but have several technical limitations.
A BBFF reduced with TENS nails. Arrows indicate the fracture sites before and 4 months after surgery.
Credit @ Papamerkouriou Y, Christodoulou M, Krallis P, et al. Retrograde Fixation of the Ulna in Pediatric Forearm Fractures Treated With Elastic Stable Intramedullary Nailing. Cureus 12(5): e8182. doi:10.7759/cureus.8182. Accessed 18th Jan 2021
“Crossed K-wires” are often used for distal (toward the wrist) radius and/or ulna fractures. Longer wires may occasionally be passed down the bone canal in the place of intramedullary TENS nails in smaller children.
It must be noted that the use of TENS nails, Rush nails or K-wires (crossed or otherwise) does not take away the need for traditional cast application (with the exception of severe, open fractures as discussed above).
In younger children, if wires have not been buried under the skin, Dr. Maina may discuss the option of removing K-wires on an outpatient basis. This means that your little one doesn't necessarily need to undergo readmission.
In older children, and certain fracture patterns, due to a prolonged healing time, Dr. Maina will leave the K-wires buried to avoid the risk of pin site infection. Buried wires are removed in the OR during a second surgical procedure.
Plate and screw fixation is typically reserved for fractures in older children or that are unstable and/or comminuted (multiple fragments). Plates may also be considered in refractures, if it is unlikely that a TENS nail will be successfully passed across the fracture site due to occlusion of the bony canal with callus (healing bone).
The advantage of plating is it's stability as a fixation technique. This permits early movement of the arm and joints above and below the fracture. The disadvantages of plating include damage to surrounding soft tissue (due to the necessity of extensive skin and soft tissue dissection at the time of surgery), disruption of the periosteum (in children, the periosteum is the main supply of blood to the bone), and nonunion (a late complication that may arise from a disrupted periosteal blood supply).
What else should I know about implants in children?
Surgery using implants may result in two procedures – the first to insert the implant(s), and a second to remove the implant(s) in the growing child.
Implants are removed for several reasons:
Nails and wires are often in close proximity to joints and may result in stiffness and a reduced range of movement.
Retained implants risk potential bony overgrowth, which would complicate their removal (or the treatment of subsequent orthopaedic conditions) later in childhood or adulthood due to their incorporation into the bone.
Periprosthetic fractures (around plates) may occur in children involved in contact sports. Removal mitigates the development of this risk.
Hypersensitivity reactions may be addressed through a "removal of hardware”.
Soft tissue irritation might only respond to explantation of the irritant (nail/wire(s)/plate and screws).
In conclusion, while many fractures in children unite with ease, their course of recovery may involve rigorous care.
This blog post should not substitute medical treatment or a specialist assessment. It is important that you are given information specific to your child and their injury an supported by scheduled, regular clinical follow-up.
With appropriate care and time, your child should happily heal and bounce back to their active, vibrant selves once more!
Dr Anne Maina
Specialist Orthopaedic surgeon
MBBCh (Wits), FC Orth (SA), MMed Ortho (Wits) CIME
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