BACKGROUND
Forearm fractures are one of the commonest fractures seen in adults and children. Closed manipulation is usually the first-line treatment for significantly displaced fractures. The method of closed reduction of long bone fractures has been well-described.1,2 Like any skill, the art of manipulation can only be perfected by observation and practice. A full understanding of the concept behind fracture reduction and immobilisation is crucial to medical training. Teaching models are essential in order to allow students to visualise the concept fully. Charnley initially used wood and leather to described the fracture model.1 We introduce an alternative teaching model, which is readily available, cheap and easy to understand.
TECHNIQUE
The model was made using ‘Collar'n'Cuff’ versatile sling material.1 Take a 30-cm strip. This represents a forearm bone. Cut through the sling material, leaving the outer covering on one side intact. The cut outer material represents the torn periosteum on the tension side of the injury. The cut sponge represents the fractured bone ends. The intact material cover represents the periosteum that remains intact on the compression side of the injury. Overlap the sponge to represent a fully transulated fractured bone end (Fig. 1).
Figure 1.
representation of a fully transulated fractured bone end.
It is impossible to reduce such a fracture by straight-line pull because of the strong fibrous layer of the intact periosteum. Forceful manipulation can rupture the remaining intact periosteum, de-stabilise the fracture and may lead to non-union or mal-union. Therefore, to affect a safe reduction, the surgeon must reproduce the deformity at the time of injury. To demonstrate this using our mode, the smaller fragment is manipulated into a position at 90° to the longer fragment (Fig. 2).
Figure 2.
Manipulation of smaller fragment.
To demonstrate the reduction, the sponge is then slid so that the edges match and then the sponge ends reduced. The fracture is then reduced by forceful volar flexion whilst maintaining the traction against the intact material ‘periosteum’ (Fig. 3).
Figure 3.
Forceful volar flexion.
The three-point moulding technique of plaster cast immobilisation is represented in our model by the three points that maintain reduction against the intact material (Fig. 4).
Figure 4.
The three-point moulding technique.
References
- 1.Charnley J. The Close Treatment Of Common Fractures. 4th edn. Cambridge: Colt Books; 1999. [Google Scholar]
- 2.Rang M. Children's Fractures. New York: Lippincott Williams and Wilkins; 1983. [Google Scholar]