EWJ Dec 2023 - Journal - Page 55
• Post-Traumatic Amnesia of less than 24 hours;
• Loss of consciousness of no more than 30 minutes;
• Temporary confusion; and
• Normal brain scan (this would include all types of
scan)
As this system has only recently been published its
clinical utility has yet to be established but the aim was
to present a single taxonomy to promote a common
understanding of MTBI.
What might "complicating" factors be in the context of
MTBI? These were described by McCrea (2008) who
differentiated between Uncomplicated MTBI where
there is no neuroradiological evidence of injury and
Complicated MTBI where there is positive neuroradiological evidence of traumatic injury. Recent research has upheld the clinical utility of this distinction
but "the size of cognitive deficit (even) in complicated
MTBI was small and unlikely to cause significant disability” (Hacker et al, 2023 p.3). This is a change of
position from earlier research which had reported
that complicated MTBI would lead to similar outcomes to moderate TBI by increasing the risk of slow
or incomplete recovery (Williams et al, 1990 in McCrea, 2008) and by the patient taking considerably
longer to return to work (Iverson et al, 2012).
This has to be in the absence of drugs, medication,
alcohol or penetrating head injury. The WHO system is considered to be more helpful in considering
milder brain injuries as the MAYO system is, “not able
to get around some of the difficulties inherent in TBI
classification especially at the milder end of the spectrum” (Friedland, 2013). It is also noted that, “...there
is no guide as to long-term prognosis in the Mayo system” (Friedland & Hutchinson, 2013) and so it has
little clinical utility.
The American Congress of Rehabilitation Medicine
Diagnostic Criteria for MTBI (Silverberg et al, 2023)
has recently developed a new classification system by
consensus which only differentiates between "MTBI"
and "suspected MTBI" but posits that there must be
a biomechanically plausible mechanism of injury (including acceleration / deceleration injury with no contact to head). One or more of the following criteria
must be met:
1. Clinical Signs: LoC; alteration of mental status
following the injury; complete or partial amnesia
for events immediately following injury; other acute
neurological signs
The table below summarises all of the key information
required to classify a traumatic brain injury:
Why is it that so many patients with such minor
injuries report so many problems?
Bunnage (2013) referred to, “the role of
psychological factors in the creation and perpetuation
of symptoms following MTBI”. Researchers often comment upon the apparent disconnect between the relatively trivial nature of the index injury in such cases
and the catastrophic symptoms that are reported by
patients. Perrine & Gibaldi (2016) argued that, "Patients with relatively minor injuries can endorse a large number of severe post-concussion symptoms and complaints of
long-term sequelae that reportedly disrupt daily functioning...if any physical disorder is present, such as minor and
uncomplicated head injury, it does not explain the nature
and extent of the symptoms or the distress of the patient...the
frequency of somatoform disorder in patients presenting
with post-concussion syndrome is significant" (2016, p5).
Research has continued to report the same pattern
and Phillips stated that, "in many ways, whether
2. Acute Symptoms: confusion / disorientation;
physical symptoms; cognitive symptoms; emotional
symptoms
3. Clinical Examination / Lab Findings: cognitive
impairment; balance impairment; oculomotor
impairment; elevated blood biomarkers indicative
of intracranial injury
4. Neuroimaging: trauma-related intracranial abnormalities on CT or MRI
5. Not better accounted for by confounding factors
(pre-existing or co-occurring health conditions)
Table 1: classification systems for determining the severity of brain injury – adapted from Baxendale et al (2019)
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