Fractures of the pelvis account for less than 5% of all skeletal injuries, but it is important because it associated with:-
Soft tissue injuries and blood loss.
Because of those mortality rate exceeds 10%.
Fractures of the adult pelvis, exclusive of the acetabulum, generally are either stable fractures resulting from low-energy trauma, such as falls in elderly patients, or fractures caused by high-energy trauma that result in significant morbidity and mortality.
As is true of fractures of other bones, low-energy trauma to the pelvis generally produces stable fractures that can be treated symptomatically with crutch- or walker-assisted ambulation and that can be expected to heal uneventfully in most patients. High-energy pelvic fractures often are managed operatively, with the treatment method determined by the degree of pelvic stability remaining after the injury.
Types of injury:
Isolated fractures with an intact ring.
Fractures with broken ring (stable or unstable).
Fracture of the acetabulum; although it is ring fracture but involvement of the joint raise a special problem.
1. Avulsion fractures. A piece of bone is pulled off by violent muscle contraction usually seen in athletes.
The anterior superior iliac spine pulled off by sartorius muscle.
The anterior inferior iliac spine by rectus femoris.
The pubis by adductor longus.
Part of ischium by the hamstrings
All need only resting for few days and reassurance.
2. Direct fractures. A direct blow to the pelvis like fall from a height may lead to fracture of the iliac blade or the ischium.
Rest until pain subsides is usually all that is needed.
3. Stress fractures. Fractures of the pubic rami and around the sacro-iliac joint in severely osteoporotic and osteomalacic patients; it is usually painless and discovered accidentally.
Fractures of the pelvic ring
Because of the rigidity of the pelvis, a break at one point in the ring should be associated with disruption at a second point except
a. Fractures due to direct blow.
b. Acetabular floor fractures.
c. Ring fractures in children.
The second point break is usually not visible either it is reduced immediately or the sacroiliac joint is only partially disrupted.
Mechanisms of injury
The basic mechanisms of pelvic ring injury are:
Anteroposterior compression (APC).
Lateral compression (LC).
Vertical shear (VS).
Combinations of these.
Anteroposterior compression (APC)
Usually caused by a frontal collision between pedestrian and a car. This injury may lead to:
Fracture of the rami.
The innominate bones are sprung apart and externally rotated with disruption of the symphysis.
The anterior sacroiliac joint is partially torn.
Fracture of the posterior part of the ilium.
This is called open book injury.
Lateral compression (LC)
Side to side compression of the pelvis causes the ring to buckle and break. This is due to a side –on impact in a road accident or a fall from a height.
This injury may lead to
Anteriorly the pubic rami on one side or both sides are fractured.
Posteriorly there is severe sacroiliac strain or fracture of the sacrum or ilium, either on the same side of the pubic fracture or on the opposite side.
Vertical shear (VS)
The innominate bone on one side is displaced vertically, fracturing the pubic rami and disrupting the sacroiliac region on the same side. This is typically occurs when falls from a height on one leg. These are severe unstable injuries with gross tearing of the soft tissues and associated with retroperitoneal hemorrhage.
In severe pelvic injuries there may be a combination of the above.
The Young-Burgess (1986; 1987) system is as follows:
1. APC injury
The hallmark of the AP compression injury is pubic diastasis with or without disruption of the SI joints. The location and degree of diastasis is correlated with the magnitude of force imparted to the pelvis and with the amount of resulting instability. The AP compression causes the pelvis to open: one or both hemipelves undergo external rotation. According to the Young-Burgess classification system, 3 degrees of AP compression injury are identified.
APC- I injuries : Less than 2.5 cm of the pubic diastasis is noted, either at the symphysis or through vertically oriented rami fractures. The SI joints and posterior ligaments remain intact, and stability is maintained.
APC- II injuries : The amount of anterior diastasis exceeds 2.5 cm. In addition, diastasis occurs in 1 or both of the SI joints. This incomplete posterior arch disruption results in rotational instability. The posterior ligaments are not injured; therefore, vertical stability is preserved.
APC- III injuries : These injuries extend to the posterior SI ligaments, which are disrupted. Consequently, the pelvis is vertically and rotationally unstable.
2. Lateral compression (LC) injury
Lateral compression injury results in internal rotation of the affected hemipelvis. This internal rotation decreases rather than increases the pelvic volume. Consequently, pelvic vascular injuries and resulting hemorrhage are less common with this injury than with other injuries. Lateral compression injuries are associated with brain and intra-abdominal injuries.
The hallmarks of a lateral compression injury include sacral buckle fractures and horizontal pubic rami fractures. The Young-Burgess classification system describes 3 types of injuries.
LC- I injuries : These involve a force directed posteriorly to the lateral aspect of the hemipelvis, which results in an ipsilateral sacral buckle fractures; ipsilateral horizontal pubic rami fractures; or, less commonly, disruption of the pubic symphysis with overlap of the pubic bones. The posterior ligaments remain intact; therefore, the pelvis is stable.
LC- II injuries : These involve more internal rotation of the hemipelvis. As in type I injuries, ipsilateral sacral buckle fractures and horizontal pubic rami fractures are associated with fracture of the ipsilateral iliac wing or disruption of the ipsilateral posterior SI joint. The pelvis is rotationally unstable, but its vertical stability is maintained.
LC- III injuries : The force continues from the ipsilateral side across the midline to affect the contralateral hemipelvis. The ipsilateral hemipelvis sustains either a type I or type II injury with associated internal rotation. The contralateral pelvis undergoes external rotation. Contralateral vertical pubic rami fractures or disruption of the ligaments may occur. As in type II injuries, the pelvis is rotationally unstable but vertically stable.
3. Vertical shear injury
A vertically oriented force applied to a hemipelvis, usually by the femur, results in a vertical shear injury. At the anterior aspect, vertically oriented fractures of the pubic rami occur. Posteriorly, the ipsilateral SI joint (or occasionally the contralateral SI joint) and its associated ligaments are disrupted.
The affected hemipelvis is displaced in a cranial direction. Complete disruption of the posterior ligaments yields a rotationally and vertically unstable pelvis.
Associated injuries seen in the vertical shear pattern are similar to those encountered in type III AP compression injuries.
Clinical features and clinical assessment
Fracture of the pelvis should be suspected in every patient with serious abdominal injury or lower limb injury.
HO road traffic accident, fall from a height or crush injury.
Severe pain, swelling and bruises in the lower abdomen, perineum, thighs, scrotum or valva.
Extravasations of urine.
Symptoms and signs of bleeding and hemorrhagic shock.
Clinical features and clinical assessment
Tenderness all over the pelvic bone especially when attempt to compress or distract the pelvis.
Tender abdomen due to bleeding or intrapelvic structure injuries.
Rectal examination should be done in every case.
Clinical features and clinical assessment
Bleeding in external meatus indicates urethral injury. If no bleeding ask the patient to void and give direct look to the urine, if the patient able to void this indicates either no urethral injury or there is only minimal damage to the urethra.
Note no attempt should be made to pass a catheter, as this could convert the partial injury to complete injury.
Neurological examination should be done to exclude sacral and lumber plexus injury.
1. plain radiography: 5 views are necessary
Pelvic inlet view in which the tube is cephalad to the pelvis and tilted 30° downwards.
Pelvic outlet view in which the tube is caudad to the pelvis and tilted 40° upwards.
Right oblique view.
Left oblique view.
2. CT scan which gives accurate details and much information about the injury.
3. Urethrography for diagnosis of urethral injury
1. Early management
Treatment should not await full and detailed diagnosis. Doctor should move according to the priority of life saving measures with the already available information.Six questions must be asked and the answers acting upon as they emerge:
Is there a clear airway?
Are the lungs adequately ventilated?
Is the patient losing blood?
Is there an intra abdominal injury?
Is there a bladder or urethral injury?
Is the pelvic fracture stable or not?
After exclusion of the above, the doctor now has a good idea about the patient general condition and the associated injuries so further investigation can be done.
2. Management of severe bleeding
Treatment of shock.
External fixation to close the book.
3. Management of urethral and bladder injury.
4. Treatment of the fracture
Isolated fractures and minimally displaced fractures: need only bed rest with lower limb traction.
Open book injuries if the diastasis less than 2.5 cm only bed rest and posterior sling to close the book. If the diastasis more than 2.5 cm the book should be closed surgically either by closed reduction and external fixation or if the patient need laparotomy so open reduction and internal fixation by special plates and screws or by K. wire.
LC-II with limb length discrepancy more than 1.5 cm needs reduction and external fixation.
AP-III and VC are the most dangerous and the most difficult to treat. These are unstable fractures and needs reduction and fixation by either external fixation or plate and screws.
Open fractures are treated by external fixation.
Sciatic nerve injury.
Urogenital problem like stricture, incontinence and impotence.
Persistent sacroiliac pain due to unstable pelvis.