CHAPTER XLV. FRACTURES OF THE SHAFTS OF THE BONES OF THE LEG. The division of fractures of the leg into : Fractures of the upper ends, Fractures of the shafts and Fractures of the lower ends, is not a scientific classification of these injuries, yet it forms a work- ing basis for their consideration. There is no hard and fast line to be drawn between fractures of the shaft and fractures of the extremities. The nearer the break is located to the end of the bone the more it assumes the characteristics of a typical fracture of the extremity.
Surgical Anatomy. — The shafts of the bones of the leg are each ossified from centers which make their appearances during the seventh and eighth weeks of foetal life. That for the tibial shaft delevops first. The shaft of the tibia constitutes the main strength of the leg. It is distinctly triangular in cross-section and shows three surfaces separated from each other by three prominent borders. The anterior border is subcutaneous and may be palpated from the tibial tubercle to the internal malleolus. The external border is directed toward the fibula and has attached to it the heavy interosseous membrane. The internal border may be palpated throughout, though in well developed persons the middle portion is more or less encroached upon by the bellies of the flexor muscles of the foot.
<Callout type="important" title="Important">The weakest part of the tibial shaft is at, and just below, the junction of the middle and lower thirds, and it is here that fracture most frequently occurs.</Callout> The shaft is composed of a tube of heavy compact tissue and the fractures occurring in this region are clean cut and show no impaction or crushing of bone tissue. Comminu- tion is not infrequenth^ seen and the fracture may be multiple ; but the fragments are hard and the edges clean cut, and screws find a firm foothold when the Lane plate is employed to secure reduc- tion and immobilization.
The shaft of the tibia normally bows slightly forward while the fibula bows a little in the opposite direction. The shaft of the fibula is almost entirely surrounded by muscles which act as cushions in the presence of direct violence. The upper extremity and external malleolus are the only portions of the fibula which can be satisfactorily palpated. The lower third or fourth of the external surface of the bone may be felt between the peroneus tertius anteriorly and the peroneus longus and brevis posteriorly.
The shafts of the bones of the leg are usually both broken, though isolated fracture of either bone may occur. The fibula is more frequently fractured than the tibia. When both bones are broken the lesion in the fibula is usually at the higher level. The fracture in the tibia may be transverse, oblique, spiral, or longitudinal. Spiral and oblique fractures are quite common below the middle of the shaft and are usually the result of indirect violence. Transverse fractures are more common above the middle of the shaft and are usually due to direct violence.
<Callout type="risk" title="Risk">Anteriorly the tibia has no such protection but receives the full force of direct violence applied to the shin.</Callout> Pain, crepitus, abnormal mobility and deformity are almost uniformly present. The deformity is usually sufficient for the surgeon to recognize the condition by inspection alone.
Treatment. — The emergency treatment of fractures of the leg is of considerable importance. Some form of temporary splint should be employed in transporting the patient from the scene of the accident to the hospital or home. The greatest care should be exercised to avoid converting a simple fracture into a compound one. <Callout type="tip" title="Tip">The less the parts are disturbed at this time the less pronounced will be the traumatic reaction, during the following week.</Callout> In the reduction of fractures of the leg an anesthetic should be employed to relieve the pain and overcome muscular spasm.
<Callout type="warning" title="Warning">Pressure should not be made directly over the prominent end of a fragment lest the condition be rendered compound by penetration of the skin from within.</Callout> It is common in spiral and oblique fractures to see recurrence of deformity take place as soon as the foot is released, and it is this type of break which most needs operative treatment and internal fixation.
The treatment of fractures of the leg varies according to the amount of trauma and laceration sustained by the soft tissues and the facility with which the fragments can be held in reduction. During the first week or ten days the leg should be immobilized in some form of temporary splint which will steady the parts and yet allow perfectly for frequent inspection and adjustments, during the onset and subsidence of swelling.
<Callout type="gear" title="Gear">The author has used both the pillow splint and the fracture-box with considerable satisfaction.</Callout> The fracture-box is made of four pieces of wood as shown in Figs. 698 and 699. The inside of the box is well padded with cotton batting to fill in the spaces between the leg and the walls of the box. The sides of the box should be hinged so they can be lowered for inspection of the limb and readjustment of the padding.
Fig. 703. — Adhesive plaster applied for traction and coun- ter-traction with, the short Desault splint. Adhesive on upper part of leg is applied to pull upward while that on the lower part of leg to pull downward when the splint is in position.
Fig. 704. — Short Desault splint in position, with padding about leg. Tightening the screw at the foot of the splint affords traction and counter-traction.
Key Takeaways
- The weakest part of the tibial shaft is at, and just below, the junction of the middle and lower thirds.
- Spiral and oblique fractures are common in the lower third of the shaft due to indirect violence.
- Treatment involves immobilization with a temporary splint and reduction under anesthesia.
Practical Tips
- Always use caution when applying pressure directly over the fracture site to avoid converting a simple fracture into a compound one.
- Regularly inspect and adjust the padding in a fracture box or splint to ensure proper fit and comfort for the patient.
- Use anesthetic during reduction of fractures to relieve pain and overcome muscular spasm.
Warnings & Risks
- Avoid direct pressure on the prominent end of a fragment, as it can lead to skin penetration and compounding the injury.
- Be aware that spiral and oblique fractures may recur after initial reduction without proper immobilization.
- Recognize that severe trauma can result in extensive soft tissue damage and potential gangrene.
Modern Application
While many of the techniques described in this chapter are rooted in historical practices, the principles of fracture management remain relevant today. Modern splints and fixation devices have improved upon traditional methods but the importance of proper immobilization, pain relief, and careful handling during transport remains critical for survival scenarios.
Frequently Asked Questions
Q: What is the weakest part of the tibial shaft?
The weakest part of the tibial shaft is at, and just below, the junction of the middle and lower thirds, where fractures most frequently occur.
Q: How can a fracture be converted from simple to compound during transport?
Direct pressure on the prominent end of a fragment can lead to skin penetration and compounding the injury, making it more complex and potentially dangerous.
Q: What are some common types of fractures in the shafts of the leg bones?
Common types include transverse, oblique, spiral, or longitudinal fractures. Spiral and oblique fractures are particularly common below the middle of the shaft due to indirect violence.