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Treatment injury case study
February 2013 – Issue 52
Sharing information to enhance patient safety
Theatre positioning
EVENT: INJURY: Radial nerve compression
Case Study
Jeannie, a 41-year-old secretary, had an injury to her radial nerve during gynaecology
surgery. Other than menorrhagia and medicated hypertension, Jeannie was generally well.
Following an elective total laparoscopic hysterectomy the
nurses noted that she had a reddened area on her upper arm. In
the next few hours Jeannie’s hand became increasingly painful
and she developed a wrist drop. Whilst Jeannie was able to
oppose she was unable to extend her wrist or fingers and was
scoring the pain 8 out of 10.
A radial nerve injury at the humerus level due to positioning
during anaesthetic was diagnosed. Jeannie’s arm and hand
were elevated on a pillow but remained slightly swollen.
Following review by the house surgeon Jeannie was
commenced on gabapentin 300mg three times daily, and
physiotherapy and pain service reviews were requested.
The pain service review found that Jeannie was still complaining
of intense pain in the radial distribution of her left hand. The
hand was swollen and had a definite difference in sensation,
as well as weakness of extension of her wrist and fingers. The
pain specialist advised continuing with the gabapentin but also
starting Jeannie on amitriptyline 10mg at night and a ketamine
infusion. The physiotherapy review findings were very similar
but did note some improvement since the medications had
Key points
• Iatrogenic nerve injuries are often preventable
and this is the responsibility of the whole
theatre team
• Preventive actions include appropriate
positioning and padding of at-risk sites
• Early diagnosis and treatment assists optimal
recovery
• Treatment includes pain management,
physiotherapy and orthosis to prevent
contracture
• “The dos and don’ts of arm positioning under
general anaesthesia”, a New Zealand-specific
educational poster, can be obtained from the
New Zealand Society of Anaesthetists (nzsa@
anaesthesia.org.nz) or from Professor Stringer
as a PDF ([email protected]).
been started. Jeannie was shown some gentle finger and thumb
exercises, which she found helpful.
In the next 24 hours there was some easing in the pain
but Jeannie still had paraesthesiae and loss of sensation,
particularly over the dorsum of the index finger and first web.
Jeannie was discharged with an appointment to be seen at the
outpatient pain service clinic a month later.
On review at the clinic the swelling had gone and the pain was
only minor, although there was still some residual weakness
and numbness. Jeannie was reassured that, although it
could take time, generally patients with this injury have a
full recovery. The specialist also advised her to wean off the
gabapentin. Jeannie’s treatment injury claim for radial nerve
injury was accepted and ACC was able to assist with her
ongoing treatment and weekly compensation.
Expert Commentary
Mark Stringer, Professor of Anatomy, MS FRCP FRCS
Jeannie’s otherwise successful surgery was complicated by an
iatrogenic nerve injury (INI) secondary to malpositioning under
general anaesthesia. The radial nerve is vulnerable to external
compression where it spirals around the back of the humerus.
As a result of the extrinsic compression of her radial nerve she
developed a distressing and disabling wrist drop.
In a recent analysis of treatment injury claims accepted by ACC
in 2009, the single most common cause of INI, accounting for
more than 10% of claims (35 in total), was malpositioning under
general anaesthesia. More than half of these malpositioningrelated nerve injuries occurred in orthopaedics or general
surgery but no surgical specialty was exempt. The ulnar nerve
at the elbow and the brachial plexus are most frequently
injured. The cause of the injury is typically (i) excessive stretch
of the nerve, such as when the patient’s elbow is flexed more
than 90º or their shoulder abducted by more than 90º for
prolonged periods, or (ii) external compression of the nerve
against a bone by a rigid structure such as an anaesthetic
screen pole, an arm board or the edge of the operating table.
Thus the ulnar nerve can be compressed against the medial
epicondyle of the humerus, the common peroneal (fibular)
nerve against the neck of the fibula or, as in this case, the radial
nerve against the back of the humerus.
Case study
The unconscious patient is at risk of such injuries because they
are unable to reposition the limb in response to neurological
symptoms. The key is prevention, which is the joint responsibility
of the whole theatre team. Being aware of which nerves are
particularly at risk and in what circumstances is crucial. If a
perioperative nerve injury occurs, successful treatment depends
on prompt and accurate diagnosis and referral to an appropriate
specialist, since delayed treatment jeopardises optimal recovery.
In addition to expert pain management and physiotherapy,
which Jeannie received, any areas of sensory impairment must
be protected from injury and an orthosis, such as a wrist or foot
splint, may need to be fitted to prevent a contracture.
A New Zealand-specific guideline based on the recommendations
of the American Society of Anesthesiologists Task Force on
Prevention of Perioperative Peripheral Neuropathies and, in
consultation with local anaesthetists an educational poster, was
developed in 2011 to provide guidelines on how to safely position
the upper limbs of adults undergoing general anaesthesia. The
poster entitled “The dos and don’ts of arm positioning under
general anaesthesia” is available from the New Zealand Society
of Anaesthetists ([email protected]) or a PDF can be
obtained from the author.
William Taine, MBChB FRACS (Orthopaedics)
INIs may arise as direct or indirect injuries from surgery, retraction
or injection, or be pressure injuries related to positioning.
Reviews have suggested elements of individual susceptibility
associated with pre-existing diseases such as diabetes, tobacco
use, and an anatomical predisposition such as arthritis,
particularly with regard to the ulnar nerve at the elbow. The
common pressure sites are well established and many injuries
ought to be preventable.
Nerve Injury & Site
Peroneal nerve at the knee
Sciatic nerve in the posterior
thigh
Brachial plexus and cervical
nerve roots in the neck
Radial, ulnar and median
nerves at the arm, elbow and
wrist
Causation
Positioning in lithotomy
Bolsters used in lower limb
surgery
Rotation and lateral flexion
away from the surgical site
during shoulder surgery, and
with sternotomies
Direct pressure or posture
In 2011 the American Society of Anesthesiologists published
guidelines on INI prevention, which is considered the
responsibility of the whole theatre team: anaesthetist, surgeon
and nursing staff. Preventive actions include appropriate
positioning and padding of at-risk sites, whilst early diagnosis with
timely acknowledgement, advice and management as required
will assist the patient in dealing with this type of injury.
The diagnosis of an INI can usually be made clinically based on
symptoms and signs. In this case, sensory loss on the dorsum of
the first web of the hand, with motor loss affecting wrist and finger
extension, suggests radial nerve palsy. The most common site for
this is the mid zone of the posterior arm, where the radial nerve is
applied to the humerus deep to triceps. Extension of the limb in
external rotation, particularly across an edge or ridge, is the most
common cause.
Recovery from a peripheral INI is usually spontaneous and often
complete; however, residual deficits may remain, particularly
if pressure has been high and/or sustained. The outcome and
time to recovery will depend on whether the lesion is functional
(neuropraxia) or more severe (axonotmesis).
Management following the diagnosis of a pressure injury to a
peripheral nerve is expectant. Neuralgic pain may occur during
recovery and require active management. Also appropriate may
be advice on the protection of insensate areas, physiotherapy to
prevent stiffness, and splintage for function, particularly if there
is a foot drop or wrist drop (as in this case). Investigations such as
nerve conduction studies or electromyography may confirm the
diagnosis and assist in establishing a prognosis, or in monitoring
recovery if the expected pattern of return of function does not
occur.
References
• References/websites available upon request.
Claims information
Between 1 July 2005 and 12 January 2013 ACC received 1,888 claims relating to nerve
injury associated with surgery, of which 1,548 were accepted. The most common
reason for declining was that there was no injury, no causal link between the injury
and treatment or that the injury was an ordinary consequence of the treatment.
How ACC can help your patients following treatment injury
Many patients may not require assistance following their treatment injury.
However, for those who need help and have an accepted ACC claim, a
range of assistance is available, depending on the specific nature of the
injury and the person’s circumstances. Help may include things like:
About this case study
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This case study is based on information amalgamated from a number of
claims. The name given to the patient is therefore not a real one.
•
contributions towards treatment costs
weekly compensation for lost income (if there’s an inability to
work because of the injury)
help at home, with things like housekeeping and childcare.
No help can be given until a claim is accepted, so it’s important to
lodge a claim for a treatment injury as soon as possible after the
incident, with relevant clinical information attached. This will ensure
ACC is able to investigate, make a decision and, if covered, help your
patient with their recovery.
ACC6591 ©ACC 2013
Printed in New Zealand on paper sourced from well-managed
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The case studies are produced by ACC’s Treatment
Injury Centre, to provide health professionals with:
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an overview of the factors leading to treatment injury
expert commentary on how similar injuries might be avoided in
the future.
The case studies are not intended as a guide to treatment injury cover.
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