Humeral Shaft Fracture Flashcards
Who is commonly affected by humeral shaft fractures?
Humeral shaft fractures are common injuries. Like many orthopaedic injuries, they have a bimodal distribution, occurring in both younger patients due to high energy trauma and in elderly patients following low impact injuries.
Which nerve is at risk in humeral shaft fractures?
Due to the location of the radial nerve within the spiral groove, there is a reasonably high risk of injury; the overall incidence is around 10%, although this is much higher (~25%) in Holstein-Lewis fractures
Where is the radial nerve located?
Due to the location of the radial nerve within the spiral groove, there is a reasonably high risk of injury in humeral shaft fractures.
What are the risk factors for humeral shaft fractures?
The risk factors for humeral shaft fractures include osteoporosis, increasing age, or previous fractures.
How do the majority of humeral shaft fractures occur?
These fractures may occur from a fall directly onto the outstretched limb or falling laterally onto an adducted limb.
What are the clinical features of humeral shaft fractures?
Pain and deformity are the predominant features of this injury. These fractures may occur from a fall directly onto the outstretched limb or falling laterally onto an adducted limb.
On examination, ensure you carefully check and document the neurovascular status. Assess for open wounds and any suspected concurrent injuries or fractures, particularly if there was a high-energy impact involved.
If there is damage to the radial nerve in a humeral shaft fracture, how will this present?
If the radial nerve is involved, the patient may also complain of reduced sensation over the dorsal 1st webspace and weakness in wrist extension.
What is a Holsten-Lewis fracture? And how does this affect the radial nerve?
A Holstein-Lewis fracture is a fracture of the distal third of the humerus resulting in the entrapment of the radial nerve.
The resultant neuropraxia to the radial nerve will result in loss of sensation in the radial distribution and a wrist drop deformity. Surgical management is indicated in such cases.
What investigations should be ordered for humeral shaft fracture?
Anteroposterior (AP) and lateral plain film radiographs of the humerus are usually that is all that is required. The elbow and shoulder should be visible.
In severely comminuted cases, CT imaging may be requested for pre-operatively planning, although this is not routinely done.
Briefly describe conservative management of humeral shaft fractures
The mainstay of management is the re-alignment of the limb and the majority of humeral shaft fractures can be treated conservatively in a functional humeral brace. In most fractures of the diaphysis, this should be with a humeral brace.
When is conservative management used instead of surgical? And how effective is this?
Fractures that are <20o anterior angulation, <30o varus or valgus angulation, and with <3cm of shortening are typically deemed suitable for conservative management, requiring regular follow-up with repeated plain film imaging. Around 90% of patients will go on to full union within 8-12 weeks.
Briefly describe surgical management of humeral shaft fractures
Surgical fixation is needed in a minority of patients and will typically involve open reduction and internal fixation with a plate. This permits return to work slightly quicker than in conservative management.
Intramedullary nailing may be indicated in the presence of pathological fractures, polytrauma, or severely osteoporotic bones.
What are the complications of a humeral shaft fracture?
In most cases the prognosis is good, with minimal impact on function once the fracture has healed. Non-union and mal-union are important, albeit fortunately rare, complications to consider in humeral shaft fractures.
Varus angulation is slightly more common with transverse fractures, however rarely causes functional limitations, as the shoulder has such a vast range of motion that most deformities in the humerus can be accommodated for.
Around 90% of radial nerve injuries will improve within 3 months without any intervention.
