Orthopaedics- Trauma- Regional Trauma

Question 1

Why do pelvic fractures occur in a) young patients, b)older patients?

Answer 1

a) Due to high energy

b) Older patients with osteoporosis can sustain pubic rami fractures from low energy injuries

Question 2

What is the pelvic rim formed from?

Answer 2

Sacrum
Ilium
Ischium
Pubic bones
Strong supporting ligaments

Question 3

What structures (apart from bone) are prone to injury with pelvic fractures?

Answer 3

Branches of the internal iliac arterial system
The pre-sacral venous plexus
Nerve roots and branches of the lumbo-sacral plexus

Question 4

What are the 3 general patterns of pelvic fracture?

Answer 4

Lateral compression fracture
Vertical shear fracture
Anteroposterior compression injury

Question 5

Lateral compression fractures.

a) What causes lateral compression fractures?
b) Describe the fracture.
c) What are fractures through the pubic rami or ischium accompanied by?

Answer 5

a) A lateral compression fracture occurs with a side impact (e.g. RTA)
b) One half of the pelvis (hemipelvis) is displaced medially.
c) Sacral compression fracture or SI joint disruption

Question 6

Vertical shear fractures.

a) What causes these fractures?
b) Describe the fracture.
c) What other structures are at risk of injury?
d) How will the leg on the affected side appear?

Answer 6

a) Axial force on the hemipelvis (e.g. fall from height, rapid deceleration).
b) The affected hemipelvis is displaced superiorly.
c) The sacral nerve roots and lumbosacral plexus are at high risk of injury and major haemorrhage may occur.
d) The leg on the affected side will appear shorter.

Question 7

Anteroposterior compression injuries

a) What do these injuries result in?
b) What happens as a consequence of these injuries?

Answer 7

a) Wide disruption of the pubic symphysis- open book pelvic fracture.
b) Substantial bleeding from torn vessels occurs, and as the pelvic volume increases exponentially with the degree of displacement, with widely displaced injuries the pelvis can contain several litres of blood (i.e. the entire circulating volume) before tamponade and clotting will occur.

Question 8

a) How should open book pelvic fractures initially be managed?
b) How can this be achieved temporarily?
c) What would provide more secure initial stabilization?

Answer 8

a) They should be promptly reduced and the pelvic volume should be minimized to allow tamponade of bleeding to occur.
b) Manual manipulation and application of a tied sheet or special pelvic binder will hold the reduction temporarily.
c) An external fixator will provide more secure initial stabilization

Question 9

What may give some stability and limit further bleeding in a vertical shear fracture?

Answer 9

Application of skin traction

Question 10

What may be required if there is ongoing haemodynamic instability after a pelvic fracture?

Answer 10

Angiogram and embolization or open packing of the pelvis if laparotomy is required for coexisting intra-abdominal injuries.

Question 11

With a pelvic fracture, what does blood at the urethral meatus signify?

Answer 11

Bladder or urethral injury.

Urinary catherization may risk further injury.

Question 12

a) What must be carried out to assess sacral nerve root function and look for the presence of blood?
b) What does the presence of blood indicate?
c) If blood is present, what should happen?

Answer 12

a) PR exam
b) A rectal tear. This renders the injury an open fracture and carries a higher risk of mortality
c) General surgical review is mandatory and defunctioning colostomy may be required.

Question 13

Describe a) the stability and b) the management of the following fractures.

1. Minimally displaced pelvic fracture.
2. Substantially displaced pelvic fracture.
3. What is required to evaluate the location of the fractures and the degree of displacement?

Answer 13

1. a) Stable b) Treated conservatively with protected weight bearing for a couple of months.
2. a) Less stable, greater risk of chronic pain and poor function. b) Usually treated with ORIF.
3. CT scan

Question 14

a) From the 3 main types, what type of pelvic fracture are low energy pubic rami fractures in the elderly?
b) Where is the 2nd “break in the ring”?
c) How are these managed?

Answer 14

a) Minimally displaced lateral compression injuries
b) sacral fracture or SI joint disruption posteriorly.
c) Conservatively

Question 15

Are acetabular fractures usually high or low energy injuries?

Answer 15

High energy injuries in younger patients

Can be low energy injuries in older patients.

Question 16

What may fractures of the posterior wall of the acetabulum be associated with?

Answer 16

Hip dislocation

Question 17

How are acetabular fractures imaged?

Answer 17

X-ray: pattern of fracture can be difficult to determine on plain X rays, and oblique views may help.
CT scans: help determine the pattern of fracture and are essential for surgical planning.

Question 18

How are undisplaced/small wall acetabular fractures treated?

Answer 18

Conservatively

Question 19

How are unstable or disaplaced acetabular fractures treated?

Answer 19

In the younger patient: anatomic reduction and rigid fixation to reduce the risk of post traumatic OA
Older patients may be treated with total hip replacement.

Question 20

What causes the majority of proximal humerus fractures?

Answer 20

Low energy injuries in osteoporotic bone due to fall onto the outstretched hand or directly onto the shoulder.

Question 21

a) What is the most common pattern of proximal humerus fracture?
b) What other fractures can also occur?

Answer 21

a) Fracture of the surgical neck with medial displacement of the humeral shaft due to pull of the pectoralis major muscle. The greater and lesser tuberosities may also be avulsed with the attachments of the rotator cuffs.
b) Isolated fractures of the greater tuberosity and head-splitting intra-articular fractures can also occur.

Question 22

How is a minimally displaced proximal humerus fracture treated?

Answer 22

Conservatively with a sling and gradual return to mobilization.

Question 23

How are displaced proximal humerus fractures treated?

Answer 23

The position often improves once muscle spasm settles.
Persistently displaced fractures are usually treated with internal fixation (plate, screws, wires or intramedullary nail).

Question 24

Which is more common: anterior or posterior shoulder dislocation?

Answer 24

Anterior shoulder dislocation.

Posterior dislocations only make up 2-5% of all shoulder dislocations.

Question 25

What causes traumatic anterior shoulder dislocation?

Answer 25

An excessive external rotation force or a fall onto the back of the shoulder.
Can also occur due to a seizure (watch for bilateral dislocations).

Question 26

What is a Bankart lesion?

Answer 26

When anterior dislocation of the shoulder results in detachment of the anterior glenoid labrum and capsule.

Question 27

What is a Hill-Sachs lesion?

Answer 27

When the posterior humeral head impacts on the anterior glenoid producing an impaction fracture of the posterior head (in anterior shoulder dislocation).

Question 28

a) What can happen to the axillary nerve in shoulder dislocation?
b) What can happen to other nerves of the brachial plexus and the axillary artery?

Answer 28

a) It can be stretched as it passes through the quadrilateral space
b) They can be stretched or compressed

Question 29

What does a shoulder dislocation look like?

Answer 29

There is loss of symmetry, and loss of roundness of the shoulder
The arm is held in an adducted position supported by the patient’s other arm.

Question 30

What is the principle sign of axillary nerve injury?

Answer 30

Loss of sensation in the regimental badge area

Question 31

What confirms shoulder dislocation?

Answer 31

X-ray

Question 32

Which fractures can occur with shoulder dislocation?

Answer 32

Fractures of the surgical neck and greater tuberosity.

Question 33

What is the mainstay of treatment for anterior shoulder dislocation?

Answer 33

Closed reduction under sedation or anaesthetic
Neurovascular assessment before and after reduction
Radiographs are repeated to confirm reduction.
Patient is placed in sling for 2-3 weeks to allow the detached capsule to heal then rehabilitation with physiotherapy is commenced.

Question 34

Which shoulder dislocations may required open reduction?

Who may present with these?

Answer 34

Delayed presentation dislocations, as these may be difficult to reduce by closed means.
Alcoholics.

Question 35

How are fracture-dislocations involving a) the greater tuberosity and b) the surgical neck treated?

Answer 35

a) This usually reduces to an acceptable position with reduction of the shoulder, however ORIF is usually required if it remains displaced.
b) Usually require surgery

Question 36

How is the risk of recurrent shoulder dislocation predicted?

Answer 36

By the age of the patient at the time of initial dislocation: patients less than 20 have an 80% chance of re-dislocation
Patients over 30 have a 20% risk of further dislocation
Re-dislocation rate reduces further with increasing age.

Question 37

What do many surgeons advocate for patients under the age of twenty at the time of their first shoulder dislocation?

Answer 37

Stabilization surgery

Question 38

How are recurrent shoulder dislocations stabilized?

Answer 38

By a Bankart repair, with reattachment of the torn labrum and capsule by arthroscopic or open means.

Question 39

a) Which patients may be more prone to shoulder dislocations?
b) What are their shoulder dislocations like?
c) What is the mainstay of treatment for these patients?

Answer 39

a) Patients with marked ligamentous laxity
This may be idiopathic generalized ligamentous laxity or hypermobility due to a connective tissue disorder (Ehlers-Danlos syndrome, Marfan’s syndrome)
b) Atraumatic multidirectional dislocations which can be painful
c) Physiotherapy to strengthen the rotator cuff muscles which are secondary restraints to dislocation.

Question 40

What causes posterior shoulder dislocations?

Answer 40

A posterior force on the adducted and internally rotated arm.

Question 41

What is the main radiographic finding of a posterior shoulder dislocation?

Answer 41

The “light bulb” sign where the excessively internally rotated humeral head looks like a light bulb on an AP view.
Lateral xray views assist the diagnosis.

Question 42

What is the mainstay of treatment for posterior shoulder dislocations?

Answer 42

Closed reduction and a period of immobilization followed by physiotherapy.

Question 43

a) When do injuries of the acromioclavicular joint usually occur?
b) What injuries can the joint sustain?

Answer 43

a) After a fall onto the point of the shoulder.

b) The joint can be sprained, subluxed or dislocated

Question 44

Which ligaments are damaged in a)AC joint subluxation and b) AC joint dislocation?

Answer 44

a) The acromioclavicular ligaments are ruptured
b) The acromioclavicular ligaments are ruptured and the coracoclavicular ligaments (conoid and trapezoid ligaments) are also disrupted

Question 45

How are AC injuries treated?

Answer 45

Usually conservatively, wearing a sling for a few weeks followed by physiotherapy.
Surgery (reconstruction of the coracoclavicular ligaments) is reserved for those with chronic pain.