External fixation is currently the most commonly used method of treating complex fractures, such as shaft fractures that extend to the metaphysis and joint, in the absence of or delayed consolidation, and in fractures with infections.
The external fixator is part of the standard therapy for open fractures and in patients with multiple injuries.
The advantages of these externally mounted holding devices are the ease of use, high stability, good access to the lower limb for wound care and treatment of soft tissue; in addition, early walking is made possible.
The main disadvantage of external fixators is the high rate of complications associated with the holding structure.
Much of it has to do with the nails: infections of the nails, loosening and breakage.
The high number of infections can be reduced by accurately inserting the fixator pins and carefully controlling the pin progress.
The risk increases the longer the fixator is attached to the bone, so this fixation should be kept to a minimum.
Other surgical procedures are: dynamization, bone grafting and the introduction of intramedullary nails.
Intramedullary nailing is the most appropriate method for shaft fractures of tubular bones.
The main indication for the use of an intramedullary nail is unstable shin shaft fractures.
Decisive factors that classify a fracture as unstable are the severity of the soft tissue injuries, the joint extension radius, an initial full displacement of the fragments and fragmentation that exceeds 50% of the bone circumference.
If there are transverse fractures or fibula fractures, this is an indication that the impact was carried out with high energy expenditure and conservative treatment should therefore not be an option.
The aim of treatment is to fuse the bone within a reasonable period of time. The results would have to be comparable to those of conservative treatment.
The intramedullary nails are ideal for closed shaft fractures, oblique fractures, transverse fractures and simple fractures, with or without fragmentation.
Indication is the extension of a shaft fracture to the proximal (body-centered) and distal (body-centered) bone end (metaphysis).
Dynamization is a procedure in which the fixator is modified externally to allow axial pressure and micro-movements without allowing rotation and losing axis orientation.
This makes sense because the micromovements of the nail and the axial jerk promote and accelerate the formation of the bone callus.
Micro movements of 0.5 mm are ideal; if they are larger, they could cause damage.
If the intramedullary nail has been fixed by two or three screws, the dynamization consists in removing at least one screw; first the proximal and later possibly the distal screw.
The early decrease of the external holding structure and the application of a plaster cast have shown different results, in the majority of cases with delayed or completely absent bone healing.
If the frame is to remain attached to the bone even after the soft tissue has healed until the fracture has grown together, a posterior/lateral bone transplant should be performed in the early phase.
The advantage of this approach is that a large volume of bone can be transplanted into a well-perfused area, far from the damaged tissue structures located in front and inside.
Before performing this bone grafting, a transitional period may be necessary during which the wound is treated with antibiotics.
After an initial stage, the external fixator can be replaced with intramedullary nails, but the risk of infection is relatively high.
Contraindications include osteoporosis, poorly controlled diabetes, predictable uncooperative patient behavior (compliance), hemiplegia (paralysis of a muscle group), quadriplegia (paralysis of all four extremities), paraplegia (paralysis of both legs), AIDS and hepatitis B virus, and severe vascular pathologies.
Postoperative measures for tibial fracture
Immediately before and after the procedure, antibiotics are prescribed (24-48 h). Taking these drugs is a therapeutic and not a prophylactic measure. Antibiotics should never be used inappropriately, even in the treatment of open fractures.
The doctor applies a rather bulky, postoperative medication and the leg must be placed high on a pillow pad for 48 hours. The internal indentation must be monitored if there is a risk of compartment syndrome.
When the patient feels better, he can move with walkers or forearm crutches. A load on the leg is allowed when nailing, but depends on the individual case.
If the wound is clean and dry, rehabilitation can begin in the water.
In the case of a simple fracture, which is caused by a not particularly strong force, the broken leg can be immediately loaded again. In the other cases, there should be no load or only a partial load.
Patients with external fixation and plating should not put weight on the leg again until signs of healing can be seen on the X-ray.
In the case of debris fractures with many fragments, a functional, well-structured knee brace is recommended for additional protection and to stimulate early healing.
When the patient can move again, he is discharged from the hospital.
The X-rays must be repeated regularly.
Specialist authors recommend time intervals of 3 weeks, 6 weeks, 3 months; the doctor can continue to schedule them every 6 weeks until the X-rays show clear signs of healing.
The functionality of the knee and ankle joint must be completely restored during bone healing.
As soon as consolidation signs are recognizable, the forearm crutches should be replaced by a walking stick.
In the case of delayed or non-progressive consolidation, bone grafting or nailing is the right measure to stimulate fracture healing.
Complications of tibial fracture
Synthetic agents and bone fragments can become infected.
In addition, the combination of injuries to the inner periost (endost) caused by the accident and necrosis of the bones can have considerable consequences.
This situation, together with the introduction of an intramedullary nail in contact with potentially contaminated tissue, increases the risk of infection.
Compartment syndrome is a temporary increase in pressure in the muscle boxes. A bruise in the area of the tibial anterior lodge can cause compartment syndrome.
Pain in the front knee can be a complication.
Possible causes include multiple injuries, fractures of other bones, presence of a proximal fastening screw, weakness of the femoral quadriceps, an undetected knee injury, and the incision itself.
The neurological damage can be caused as follows:
- by longitudinal tension,
- due to excessive pressure due to too tightly fitting plaster or orthosis,
- due to soft tissue injuries,
- through the lesion of the fibula.
Other complications: discomfort caused by the screws, leg amputation, delayed consolidation and loosening or breaking of the holding structures.
Another risk is pulmonary embolism and acute progressive lung failure (ARDS) with formation of fat droplets in the system.
Fatty embolism syndrome is defined as a complex alteration of homeostasis and occurs as a complication after pelvic fractures and fractures of tubular bones; the clinical picture corresponds to acute respiratory failure, dysfunction of the brain and rash.
This syndrome occurs within 48 hours of injury.
Results and forecast
Treatment outcome and prognosis of a shin shaft fracture depend on the fracture site, the extent of fragmentation (equivalent to the force of the trauma), degree of soft tissue injury, existing comorbidities (e.g. diabetes) and polytrauma.
Severe vascular and nerve injuries worsen the patient’s outlook.
The results vary, but always worse if there is damage to the soft tissue. The retention method is also a determining factor for healing time and prognosis.
Distal vascular injuries are more likely to be associated with amputations and show worse results after the limb is saved.
In the case of open, transverse or piece fractures, the probability of a second procedure is greater.
Smoking and related diseases can be the cause of a lack of consolidation.
With external fixation, the number of infections increases after a new procedure for the introduction of intramedullary nails, regardless of the form of treatment carried out so far.
Delayed or non-existent consolidation also often occurs in fractures with high fragmentation or instability that have been treated conservatively (i.e. not operationally).
The infection rate is particularly high in conventional surgical procedures in which a plate is inserted; These should therefore be avoided if possible.
Long-term immobilization in a functional orthosis or plaster cast can lead to severe disability.
In particular, these treatment methods show the best results in patients with fractures caused by low force.