Greenstick fractures are incomplete fractures of long bones and are They are commonly mid-diaphyseal, affecting the forearm and lower leg. They are distinct from torus fractures.
Greenstick fractures are incomplete fractures of long bones usually seen in young children, more commonly less than 10 years of age. They are commonly mid-diaphyseal and typically affect the forearm and lower leg.
How Do Greenstick Fractures occur – Mechanism of Injury
The bones of children are soft and are covered with the thick fibrous periosteum of the immature bone. The force that acts on the bones of kid bends kid’s soft bone and the bone instead of breaking completely into separate pieces, cracks on one side and other side is bent without any break [due to pliant nature of bone and thick periosteum. This is a common fracture in children because their bones are softer.
Greenstick fracture occurs when the force applied to bone results in bending of the bone and breaks the bone on the convex aspect of the bend but does not extend the break to the concave surface.
The situation is similar to bending a soft green branch of a tree [stick]. If you hold a green branch or stick and bend it, it would bend only till some time. If further force is applied, the stick would break on the convex surface.
Greenstick fracture does occur in a similar manner when a bending force acts on the bone, one of the cortex bends whereas other breaks.
The greenstick injury can result from an angulated longitudinal force applied down the bone ( fall on an outstretched arm), or a force perpendicular to the bone (a direct blow).
There would be a history of trauma, commonly related to fall during playing or a twisting injury.
Following are general signs to look at the injury site for confirming or ruling out a fracture.
The patient would present with the pain in the affected site. An older child may guard the area. Younger children may present with crying only and may not be able to point to the site of injury.
Look for the presence of bruises or tenderness in an area while examining the limb.
There could be a visible deformity.
Swelling may not be recognized in chubby fellows,
Mild deformity may get unnoticed in case of thick limbs.
So a high index of suspicion needs to be maintained. Tenderness is the most consistent sign and presence of tenderness after a trauma could help to locate the injury.
Anteroposterior and lateral x-rays of the affected part are standard imaging for a greenstick fracture. The x-rays would reveal site and deformity of the fracture.
The fractures are usually mid-diaphyseal and are always associated with angulation.
The fracture appears as incomplete fracture, with the cortical breach of only one side of the bone along with bending of the bone.
In upper limb in case of radius-ulna fractures, one bone may show clearcut greenstick fracture whereas other just appear bent. Both the bones are fractured in such a scenario [usually both bones fracture together.]
Treatment of Greenstick Fracture
The treatment of Greenstick fracture requires correction of deformity by straightening the bone manually and immobilizing it in a long cast.
The reduction of the fracture may include overcorrection to break the bent cortex and result in the completion of fracture.
In case, the angulation is minimal, correction may not be required.
In infants, angulation up to up to 30 degrees is acceptable. In older children, up to 15 degrees of angulation may be acceptable depending on the age of the patient.
Surgery is often not required for greenstick fractures due to the easy reduction of the fracture and the huge growth potential of children to correct any residual deformity.
Complications of Greenstick Fractures
Complications are rare in greenstick fractures.
Bleeding from the broken bone becomes significant in anemic children. large bleeding may occur in children with bleeding disorders.
Injury to vessel or nerve is rare.
Residual deformity could be seen in children with inadequate correction. This generally happens when the angulation is not corrected by breaking the remaining cortex.
If the angulation is unacceptable, the deformity correction may be undertaken.
Prognosis of Greenstick Fractures
Properly managed greenstick fractures have a very good prognosis and children almost always have full return of function.
After immobilization, the child should be able to attend the school after an initial break of 3-5 days or less.
How Long Does it Take for a Greenstick Fracture to Heal?
The time taken is usually around 4 weeks. Younger children take lesser time and older children more time.
[Read more about factors affecting fracture healing]
Prevention of Greenstick Fractures
The prevention strategy involves reducing the chances of injury. Ensuring protective gear during play may reduce the risk.
Children should play on a soft surface like ground rather than a hard surface like concrete. This reduces the force of impact.