Child bone fractures are treated differently from adults as their bones are still growing.
One has to be cognisant of the differences in treating the paediatric patient with the growing skeleton.
The child is not a small adult, and the growth plate, also known as the physis, has to be taken into consideration at all times.
Growth plate injuries can lead to growth arrest and subsequent deformities. As such, treatment considerations and indications are different than those for the adult patient. It follows that surgical management is also then decidedly disparate.
Fractures in children can be as common as 1 in 3 sustaining one. In children, the bones and physis (growth plate) tend to be weaker than their ligaments and adjacent supporting tissue.
Thus, fractures occur more so than ligament sprains. Thankfully the treatment is usually simple with good outcomes.
Children have a growth plate (physis) and a thick membrane overlying the bone (periosteum). These two conspire to limit displacement, assist in reduction and confer stability. Hence healing is rapid and there is the capacity for Remodelling.
Remodelling allows the child’s bones to heal and eventually resemble a normal bone even if the reduction of the fracture was not optimal, to begin with. The remodelling potential depends however on the age of the child (and the remaining growth potential) and how close it is to the physis.
The younger the child and the closer the fracture is to the physis, lends itself to a better remodelling potential. It should be noted that there are limits to remodelling.
For example, rotational deformities do not correct with remodelling. When such scenarios are present it may be prudent to opt for a more anatomical reduction which may require surgery.
Common fractures in children
1. Wrist Fractures (Distal Radius)
These are the most common fractures in children and the most common scenario is a fall on an outstretched hand.
The child presents with pain, swelling and perhaps deformity at the wrist. X-rays are performed to assess the type of fracture sustained and if the physis is involved. The most common type of wrist fracture is the buckle fracture.
These can usually be treated conservatively with a cast for approximately 2-3 weeks. These fractures are close to the physis and hence heal very well.
It can also be a case in which it is a complete fracture. However, since the growth plate is close to the fracture, there is still a good chance of healing with conservative measures in most cases, especially in the younger child.
Surgical Treatment is considered in cases where there is malrotation; considerable overlap; intra-articular involvement of growth plate; as well as when there are other associated fractures and injuries.
Surgical management involves avoiding further injury to the growth plate while achieving restoration to its position.
2. Forearm injuries
Commonly occur after a fall from height, playground or during sports. The child presents with pain associated with deformity usually and is unwilling to move the affected limb.
The fracture sustained may be incomplete or complete. Incomplete ones usually do well with conservative management. Complete ones at the shaft may present a more difficult decision with regard to decision making.
Closed reduction and immobilisation may be sufficient for the minimally displaced fractures, but unstable ones might require operative fixation.
Depending on the amount of growth potential left, intra-medullary flexible nails may be used instead of the usual more rigid plates and screws techniques used in adults.
3. Elbow Fractures
Elbow Fractures are another common injury in childhood and the most common of these is the Supracondylar Humerus Fracture.
It tends to occur in children at the ages 5-7 from an outstretched -hand fall injury which overloads the elbow, and can occur in conjunction with a distal radius injury as well.
There are several types of fracture patterns and these occur due to the varying loads and mechanisms of injury.
Surgical treatment is usually one of closed reduction and percutaneous pinning. The urgency of said surgery is contingent on whether there is a compromise to the blood supply of the elbow.
The Lateral Condyle Fracture is another common elbow injury. in the 6-10 It carries a higher risk of complications than the other elbow fractures because it is more unstable, involves the joint, is harder to diagnose, and is more prone to poor healing.
The threshold for surgical intervention of the Lateral Condyle Fracture is lower due to its risk of complications and instability.
Generally, if there is more than 2mm displacement, it would be prudent to opt for surgical fixation.
Unlike the supracondylar fracture, in this instance, a formal open reduction and internal fixation is preferred as there is often interposition of periosteum preventing a good reduction.
4. Long Bone Fractures in the upper and lower limbs
These are less commonly encountered but are not altogether rare. There are parameters for acceptable limits of angulation and rotation beyond which the deformity is not tolerated as well.
Depending on the age and type of fracture, some can be treated conservatively in a cast while others would require surgery for the aforementioned reasons as well as to confer stability.
Surgery, when performed, may involve the use of Flexible intramedullary nails in order not to impede growth.
There are varying presentations and patterns observed with the different age groups. Generally, the younger age groups do well with cast and immobilisation.
The younger patients are more amenable to treatment with cast and immobilisation. (Figure 19)
The older age groups tolerate the injury less in terms of conservative management.
If the injury falls outside of the acceptable angles, or have an unacceptable rotational deformity, and deemed to be unstable, it may require surgical stabilisation.
Once again, the amount of growth potential left drives the decision for the use of flexible intramedullary nails vs the plate and screws.
5. Ankle Fractures
Ankle Fractures affect children differently according to different age groups, in reference to the Salter-Harris Classification of Injuries.
The growth plate particularly, and the paediatric bone is more vulnerable to injury than the stronger supporting ligaments and structures. Hence, the older the child is, the more likely the child is to sustain an adult-like injury.
The most common type of ankle injury is the Type 2 SH ankle fracture. These are usually treated conservatively with reduction and immobilisation in a cast.
The younger child may present with a SH1 ankle fracture in which there is no obvious deformity discernible on X-ray. The antecedent event may seem relatively innocuous as well. Thankfully, these do well with conservative treatment and immobilisation.
Ankle Fractures become more difficult to treat as the child enters adolescence. This is because of the way the physis or growth plate, closes. It closes in a circumferential manner such that the part that closes later is more vulnerable to injury.
The Triplane Fracture is a SH4 fracture which affects children from age of 10, and may sometimes be hard to diagnose. It may thus occasionally require a CT scan to assess the fragments involved and to better surgical planning. Surgical management is prudent if there is a displacement of the fracture.
Treatment in this instance is focused more on restoring articular congruity rather than fear of growth disturbance (as the child’s growth plate is closing). Inability to restore said congruity leads to the development of arthritis in the future.
The Tillaux Fracture is a SH3 injury which affects the older adolescent 12-14. Its pattern of injury is different for the aforementioned reasons and is easier to discern than the triplane.
Treatment principles are similar in that it is predicated upon restoring articular congruity.
An intra-articular SH3 or 4 injury can also occur in the young child. While this is less common, it is not altogether unusual.
These present a more difficult problem as one has to restore articular congruity while minimising growth disturbance. The physis has to be restored anatomically as much as possible, for the inability to do so will lead to a physeal bar forming and growth deformity as a consequence.
In addition, while performing the surgical intervention, one has to be careful not to violate the growth plate any further, as this would also lead to said complications.
Figure 31. Showing a SH2 ankle fracture which involved the growth plate. It was previously fixed but the growth plate was not approximated well. Hence a physeal bar was developed with a deformity that was progressing.