Dual diagnosis of traumatic brain injury and spinal cord injury

The dual diagnosis of traumatic spinal cord injury (SCI) and traumatic brain injury (TBI) has clinical and diagnostic features of both conditions typically stemming from a single traumatic event. These events are typically blunt traumas, in the case of assaults and falls, and rapid acceleration/deceleration injuries as would be seen in motor vehicle accidents (MVAs). These injuries and the advanced interventions required can make it challenging to identify a TBI, especially a mild one, in the early stages of functional recovery. The associated issues stemming from a dual diagnosis of SCI and TBI together present a unique challenge to the practicing physiatrist, regardless of their subfield of expertise.

Epidemiology

Risk factors for dual diagnosis include male gender and involvement of alcohol intoxication at the onset of injury. The risk of sustaining a TBI along with an SCI is also correlated with level of completeness of the SCI and a more caudal injury, with cervical SCI being more commonly associated with concomitant TBI.

Depending on the risk factors, the incidence of a dual diagnosis may approach 60% according to the SCI Model Systems. The criteria for claiming a TBI include:

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Posttraumatic amnesia
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Initial abnormal Glasgow Coma Scale (GCS) score
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Abnormal brain imaging

Although the overall rate of trauma related to MVAs has declined, the aging population and associated risk of falls has led to an overall increase in TBI-related emergency department (ED) visits. There has been increased vigilance in identifying sports-related concussions in young athletes.

The breakdown of incidence of the dual diagnosis patient are as follows:

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Mild TBI (GCS 13–15) represents 64% to 73% of dual diagnosis patients
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Moderate TBI (GCS 9–12) represents 10% to 23%
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Severe (GCS 3–8) makes up 17% to 23% of cases

This roughly mirrors the prevalence of these subsets of TBI without SCI.

Evaluation and diagnosis

To assess and evaluate a dual diagnosis injury properly, a detailed screening of the medical records at the time of initial assessment should be performed. Of particular importance are:

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Confirmation of loss of consciousness (LOC)
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GCS
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Duration of posttraumatic amnesia (PTA)
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Behavioral issues
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Initial imaging

Comorbid factors that complicate the SCI presentation and may mask or mimic TBI include:

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Altered mental status caused by orthostasis
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Urinary tract infection stemming from neurogenic bladder
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Intensive care unit psychosis
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Psychoactive medications to treat pain, spasticity, and/or depression

Confounding clinical neurological indices of TBI such as hypoxia, intoxication (alcohol/other), and intubation, all occur with some frequency with SCI and can alter LOC and GCS scores.

Negative brain imaging on initial imaging can frequently mask the presence of mild or even moderate TBI, and positive findings, especially contusions, may be missed in up to 67% of cases. For up to 2 to 3 months after TBI, findings consistent with axonal shear, hemorrhages, or small contusions may be present. Diffusion tensor MRI may show brain motor pathway lesions that contribute to weakness in TBI in patients with SCI.

Possible symptoms of mild and moderate TBI include:

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Headaches
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Dizziness
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Insomnia
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Emotional irritability/lability
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Impaired memory
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Focal weakness
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Visual impairments
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Impaired communication

Rehabilitation

There are no current guidelines regarding the admission process for dual diagnosis patients. Historically, patients would be assigned to either an SCI or TBI unit based on which diagnosis is contributing most to the patient’s functional impairment and barriers to recovery. Patients with dual diagnosis are more likely to manifest behavioral issues, exhibit psychopathology, and have more severe neuropsychological impairment than patients with SCI alone. Concomitant TBI may delay one’s ability to tolerate 3 hours of therapy per day and demonstrate the potential to benefit from rehabilitation interventions, thereby delaying rehabilitation admission.

The moderate to severe TBI patient can present additional challenges, including:

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Neuroendocrine dysfunction
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Salt balance
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Obstructive hydrocephalus
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Paroxysmal sympathetic hyperactivity
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Spasticity
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Heterotopic ossification
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Agitation
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Seizures
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Dysphagia
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Depression and anxiety

The management of certain comorbidities may compromise improvement in other areas, such as treating spasticity with agents that may weaken muscular strengthening.

Data from Somner and Witkiewcz on suggested strategies for the management of moderate to severe TBI and SCI are summarized in Table 54.1 .

TABLE 54.1

Management of the Confused Patient

Adapted from Somner JL, Witkiewicz PM. The therapeutic challenges of dual diagnosis: TBI/SCI. Brain Inj. 2004;18(12):1297-1308.

Confused/Agitated	Confused/Nonagitated Inappropriate	Confused Appropriate to Automatic Appropriate
Rancho 4	Rancho 5	Rancho 6–7
Provide private room Restraints only when necessary Covering brace and feeding tube with shirt/abdominal binder Full attendant care when possible Minimize overstimulation Regular nursing care, including catheterizations Maintain sleep–wake cycles Tilt-in-space wheelchair for pressure relief Minimize agitation Frequent reorientation by staff Cotreatment with one therapist Patient instruction should be short one-step commands Rest breaks Therapy in a quiet gym Aggressive and inappropriate behavior to be dealt with firmly/instantly Involve psychology for patient family support and therapy	Therapy sessions still best in quiet area of the gym Patient responds well to structure and redirection for task completion Now able to follow one- and two-step commands consistently Rest breaks and avoidance of overstimulation Full-time supervision by staff or caregivers still important	Therapy may now focus more on spinal cord injury (SCI) rehabilitation interventions Therapy may occur in open gym Orientation group, memory logbook, and signs in room helpful Checklist and environmental cues useful in planning/initiating necessary SCI activities such as pressure relief and catheterizations Patient should be able to verbalize why braces and treatments are necessary Paraparetic should learn to don/doff brace, dress in bed, wheelchair mobility Family education Including patient and family in support group