The immature bone is not only more capable of reaction and adaptation, but also more vulnerable than the mature bone. A fracture in an immature bone can cause growth to speed up or slow down, superimposing the problems of deformity on the complications of the fracture itself.

On the other hand, children’s fractures heal very rapidly and, depending on the age of the child and direction of the deformity one can remodel by correcting the most angular malunion. The most important area of injury in the immature skeleton is the growth plate or physis.

The physis is the primary center for growth in most bones and may be divided into two zones according to their function: the zone of growth and the zone of matrix formation. The zone of growth is involved with both longitudinal and circumferential growth of bone. The physis is capable of responding to different stimuli, either compression or tension.

Any kind of stimulation of the circulation leads inevitably to a stimulation of the growth zone, and therefore, of the growth. It was believed earlier that fractures would heal with shortening so that the bone has the same length at the end of the treatment. This shortening was inaccurate as it was not possible to calculate it correctly. On the other hand an anatomical reduction and osteosynthesis in most cases leads to a lengthening (Fig. 3.1). We know today that the stimulation of growth is a result of the healing time and remodeling time. We achieve the best results if we have a biological treatment and fixation, which anatomically adapts the bone fragments, has a short healing time, and no remodeling needs. This biological principle is put into effect with the ESIN technique as the best one.

The metaphysis is the site of the most rapid changes in bone structures as the deeper physeal zones mature and the physis produces primary trabecular bone.

The circumferential growth of the diaphysis is a function of appositional bone formation by the periostium, together with osteoclastic resorption by the endosteum so as to enlarge the medullary cavity. As growth continues, the bone is capable of reducing, or even correcting, angular deformity by selective resorption and apposition, possibly driven by forces of compression and tension (Table 3.1).

In addition, healing time varies with age. Consequently, the period of immobilisation differs. Below an age of 10 years, 3–4 weeks of wearing a cast is sufficient in nearly all cases. However, above 10 years, 5–6 weeks of immobilisation are often indispensable. But we must also consider the weight of the child.

Further, fracture-types are age-related. This phenomenon is because of the typical physical properties of the bone, periost, and cartilage in children.

The factors mentioned above determine the degree of tolerable dislocation and the choice of treatment. With rising age the option of conservative treatment declines and that of osteosynthesis increases.

In childhood especially, K-wires with an additional cast, cannulated screws, intramedullary elastic nails, and adapted external fixators are suitable implants. Plate osteosynthesis is exclusively used in adolescents, as also in adults. Solid intramedullary nails should be avoided in children (Table 3.2).

In childhood, absolute stability of the fracture is not necessary, neither following surgical treatment nor after conservative treatment. The reasons for this have been discussed in the previous section. In most cases, relative stability is sufficient for immobilisation and progressive weight bearing. However with increasing age, biomechanical limits are noticed. The key influence is not age itself, but the tendency toward increased body weight and size that can be observed. Frequently, 12–14 year old children are as tall and have the same body weight as adults, which is often associated with overweight, today. Little attention has been paid to this observable fact in the current literature on pediatric traumatology. Nevertheless, therapy planning has to integrate these aspects as the clinical impact is of major concern. Therefore, in older children who are also heavier, therapy should be provided as provided to adults after fracture- treatment, particularly in shaft-fractures (Fig. 3.2).

Fracture morphology has a decisive influence on therapy, independent of the age or physical development of the child. The stability of the fracture is of primary interest. Then the completeness of the fracture is evaluated.

The recognition of a so-called “bowing-fracture” is of particular importance. This type of injury is subject to laws of its own. Bowing fractures show progressive angulation and possess only little potential for remodelling. In particular, at the forearm, where this fracture is frequent in young children, there is a good chance of ending up with bad functional results after conservative therapy (Fig. 3.3). The current treatment of choice is ESIN (elastic stable intramedullary nailing). The inserted nail equalizes the angulation of the bone with its own opposite curvature, which was applied to the nail before insertion. Further angulation is thereby prevented.

Nonetheless, for the most part, stable fractures are treated conservatively with a cast independent of the patients age. Healing of the bone occurs quickly and without problems. Immobilization between 3 and 5 weeks is nearly always sufficient. An exception is the fracture of the femoral shaft which is treated with ESIN or external fixator in most centres.

In the case of unstable fractures one should always be prepared for an operation. Even if the initial reposition of an unstable, dislocated fracture is successful, secondary dislocation may require a change from conservative to surgical therapy (Table 3.3).

Repetitive reductions or manipulations in the treatment are to be avoided. Considering the type of the fracture, the following rules should be taken into consideration:

Because the fracture type has a direct influence on the therapy, it is important to classify the fractures correctly (Table 3.4). One of the most recognized fracture classifications is the AO/OTA today (Pediatric Comprehensive Fracture Classification of Long Bones; PCCF). See chapter appendix (below) and Table 3.5.

On the other hand we have to take into account different factors of the fractures as well as the localization/displacement and stability for a correct therapeutic decision.

In addition, localization influences the choice of the treatment. The management is different if the lower or the upper extremity is involved. In childhood, even more important is the localisation of the fractured segment: diaphysis/metaphysis or epiphysis.

Although in diaphyseal fractures, stability has a decisive influence on therapy, in epiphyseal and some metaphyseal fractures, the extent of displacement of the fragments is crucial.

Epiphyseal fractures are special in two ways. On the one hand it’s an injury of the growth plate with a possible impairment of the growth; on the other hand these are always injuries of the joint with all the difficulties of this type of injury. In principle, articular incongruency has to be redressed, and interfragmentary gaps up to 2 mm can be accepted. This proceeding has not been established by scientific evidence, but justified following observations and evidence.

In these fractures, the suitable implants are cannulated screws and K-wires of all sizes. In some articular fractures, as for example the two-plane fracture of the tibia, screw fixation allows a closed procedure.

The potential for remodelling of a facture is strongly influenced by the segment involved. Knowledge of the prevailing potential for remodelling is an indispensable requirement for treating pediatric fractures (Fig. 3.4).

Metaphyseal fractures of the proximal humerus and the distal forearm have to be emphasized. As the corresponding epiphyseal plates are responsible for a major part of the length growth of these bones, remodeling has the highest capacity at this place. For this reason, fractures involving the proximal humerus or distal forearm are treated conservatively for the most part, even in older children.

Independent of the localisation of the fracture, side-to-side (so called bayonet displacement) is corrected better than axial deviation.

Adequate, correct diagnostic: Skeleton standard x-rays and special radiological examinations (Ultrasound/CT/MRI)

Even in an emergency the correct AP and lateral (at least +/− perpendicular each-other) x-rays should always be taken.

General notes to the fracture types:

The evaluation and correct assessment of an x- ray is the prerequisite for correct diagnosis. The diagnosis, therefore, represents the base of the therapy decision. The phenotype of the childlike skeleton changes from year to year, sometimes from month to month. Therefore, the exact age-related development of the child’s skeleton is important. Growth plates are very often missing—interpreted as a fracture. This often leads to non-indicated treatment. The most frequent and typical example of this is the misinterpretation of the three-dimensional form of the proximal physis of the humerus. The following table gives a summary overview of the age dependent skeleton development of the most frequent miss-interpreted skeletal regions.

On x-ray, children’s joints seem much larger than they really are (Fig. 3.5). The reason for this is the thick cartilage around the epiphysis.

To decide between conservative and surgical therapy, the four previously discussed criteria are to be taken into consideration. Experience shows that quite often all aspects of a fracture are not considered in the decision for the therapy.

The choice of operative or conservative therapy has to be based on the main goal of the treatment. Despite the fact that the treatment should be definite, an initial cast-immobilisation of a potentially stable fracture is legitimate if general anaesthesia is avoided. Radiological follow-up after 5–7 days is imperative. If progressive displacement is observed, definitive treatment is still possible, in most cases, by surgery. Outcome is not influenced negatively by a brief delay to definitive surgery.

For example, in lateral condyle fractures of the humerus, the arm is primarily immobilized if the interfragmentary gap is equal or below 2 mm. After 5–6 days, a radiological control without cast is performed. If the position of the fragments remains unchanged, cast immobilisation is continued. In the case of displacement above the tolerable limit, the radial condyle is fixed operatively (Fig. 3.6).

In addition to the theoretical knowledge required for the treatment of pediatric fractures, certain technical prerequisites are necessary, especially with regard to surgical therapy.

In childhood, implants should be adapted to body size. As stability does not have to be as high as in adults and as additional cast-immobilisation is well tolerated, very small implants can be used, especially in epiphyseal and metaphyseal fractures. K-wires and cannulated screws are particularly suitable.

For surgical therapy of shaft fractures, the various implants should be disposable, and alternatively, the surgeon should be experienced in several techniques.

An adequate surgical setting enables changes in therapy during the operation. The following essential guidelines are commonly accepted for the surgical management of shaft fractures.

A factor not to be underestimated is experience in the treatment of fractures in children. A retrospective analysis at our clinic of all femoral fractures treated with ESIN has shown that 75 % of all problems and complications have been caused by surgeons who had treated less than four fractures with this technique. This also points to the fact that the importance of the learning curve should not be underestimated. This also applies to smaller clinics, especially those that seldom treat children or see only few, individual special fractures per annum.

Unfortunately, this statement does not only apply to operative therapy but also applies to handling the plaster cast and to conservative therapy. Being able to make an adequate plaster cast is still a part of the high art of conservative therapy.

The analysis of the malunions and complications to be treated in the cases assigned to this clinic within the last 5 years, shows that 90 % of these cases came from hospitals which that only sporadically treat children.

Consequently, treatment of pediatric fractures should only be carried out by experienced pediatric surgeons who:

It is in the nature of children to be always moving. It represents a basic need in childhood. Infants hardly support being tied up. Respecting this condition, a worldwide change in therapy planning has taken place.

Children do not like bed rest for 2 to 3 days or weeks, or restriction using the upper extremity as for writing in school or everyday activities. Therefore such treatments (as plaster cast) should be things of the past for children. Absence from school is a major strain for children today. Apart from this, taking care of ill or disabled children is a difficult charge for young and working parents and the society (Fig. 3.8).

Altogether, if possible, therapy planning should take these factors into consideration. During the initial setting up of the treatment with the parents, the postoperative and post-hospital care, follow up consultations, and the effort necessary for each therapy should be mentioned.

Financial factors increasingly influence medical treatment, including pediatric traumatology. A trend towards surgical treatment approaches reflects this tendency in pediatric bone trauma. Today, an operative treatment with ESIN for a femur fracture for a 12-year-old child (including out-patient nail removal) at this clinic is around 1/3 of the cost of a conservative therapy by means of extension and spica cast.