Chapter 21 Spinal Cord Injury

Question 1

What type of SCI is most common?

Answer 1

Incomplete Tetraplegia.

Question 2

Name the 4 SCI in order from most common to least common.

Answer 2

Incomplete tetraplegia,
Complete paraplegia,
Incomplete paraplegia,
Complete tetraplegia.

Question 3

Name, in order from most common, 3 causes of SCI.

Answer 3

MVA, falls, violence, sports.

Question 4

Describe the course of the the descending corticospinal motor fibers. What is it’s function?

Answer 4

The majority of descending corticospinal motor fibers cross at the medulla to become the lateral corticospinal tract (CST). A small number of CST fibers do not decussate at the medulla and descend via the anterior CST before crossing at the level of the anterior white commissure.

Question 5

Describe the course of the ascending dorsal white columns. What is it’s function?

Answer 5

The ascending dorsal white columns cross in the medulla, via the medial lemniscus, then go on to the thalamus. These fibers carry joint position, vibration, and light touch (LT) sensation.

Question 6

Describe the course of the spinothalamic tracts. What is its function?

Answer 6

The spinothalamic tracts, which carry pain, temperature, and nondiscriminative tactile sensations, cross to the contralateral side shortly after entry to the cord in the ventral white commissure of the spinal cord.

Question 7

In SCI Sensory Classification, describe:
1-# of dermatomes to examine.
2-What 3 sensory tests are done.
3-How is sensory level determined.

Answer 7

Perform a supine sensory examination of the 28 dermatomes at the key sensory points for pin prick (PP) and LT, including rectal sensation.

The sensory level is the most caudal level with intact (grade 2) sensation for both PP and LT.

Question 8

Name the 2 parts of the Rectal sensory examination.

Answer 8

Rectal sensory examination includes evaluation of deep rectal sensation as determined by the patient’s ability to feel the examiner’s finger during digital rectal examination.

Question 9

In SCI Motor Classification, describe:
1-# of muscles to examine.
2-What 2 motor tests are done.
3-How is motor level determined.

Answer 9

Perform a supine motor examination of 10 key muscle groups and voluntary anal contraction.

The motor level for each side is the most caudal level with grade ≥3, where all muscles rostral to it are grade 5.

Question 10

How is the single neurologic level determined?

Answer 10

Determine the single neurologic level, which is the most caudal level at which both sensory and motor modalities are intact bilaterally, as defined earlier.

Question 11

Describe the difference in classifying complete SCI VS. incomplete SCI.

Answer 11

Classify injury as complete or incomplete.

Complete injuries have no motor or sensory function, including deep anal sensation, preserved in sacral segments S4-5.

Question 12

When is Somatosensory evoked potentials helpful in SCI classification?

Answer 12

Somatosensory evoked potentials (SSEPs) may be useful in differentiating complete versus incomplete SCI in patients who are uncooperative or unconscious.

Categorize by American Spinal Injury Association (ASIA) Impairment Scale (AIS) A to E.

Question 13

What is ZPP? When is it applicable?

Answer 13

Determine the zone of partial preservation (ZPP) if ASIA A. ZPP is defined as preserved segments below the neurologic level of injury (NLOI) and used in complete injuries.

Question 14

What key muscle movement pertains to C5?

Answer 14

Elbow flexion.

Question 15

What key muscle movement pertains to C6?

Answer 15

Wrist extension.

Question 16

What key muscle movement pertains to C7?

Answer 16

Elbow extension.

Question 17

What key muscle movement pertains to C8?

Answer 17

Flexor digitorum profundus of 3rd digit.

Question 18

What key muscle movement pertains to T1?

Answer 18

Small finger abduction.

Question 19

What key muscle movement pertains to L2?

Answer 19

Hip flexion.

Question 20

What key muscle movement pertains to L3?

Answer 20

Knee extension.

Question 21

What key muscle movement pertains to L4?

Answer 21

Ankle dorsiflexion.

Question 22

What key muscle movement pertains to L5?

Answer 22

Extensor hallucis longus.

Question 23

What key muscle movement pertains to S1?

Answer 23

Ankle plantar flexion.

Question 24

Sensation of what anatomic location pertains to C2?

Answer 24

Occipital protuberance.

Question 25

Sensation of what anatomic location pertains to C3?

Answer 25

Supraclavicular fossa.

Question 26

Sensation of what anatomic location pertains to C4?

Answer 26

AC joint (top part).

Question 27

Sensation of what anatomic location pertains to C5?

Answer 27

Antecubital fossa (lateral part).

Question 28

Sensation of what anatomic location pertains to C6?

Answer 28

Dorsal Proximal thumb.

Question 29

Sensation of what anatomic location pertains to C7?

Answer 29

Dorsal Proximal middle finger.

Question 30

Sensation of what anatomic location pertains to C8?

Answer 30

Dorsal Proximal 5th finger.

Question 31

Sensation of what anatomic location pertains to T1?

Answer 31

Medial epicondyle of the elbow.

Question 32

Sensation of what anatomic location pertains to T2?

Answer 32

Apex of the axilla.

Question 33

Sensation of what anatomic location pertains to T4?

Answer 33

Medial to the nipple.

Question 34

Sensation of what anatomic location pertains to T10?

Answer 34

Lateral to the umbilicus.

Question 35

Sensation of what anatomic location pertains to T12?

Answer 35

Inguinal ligament.

Question 36

Sensation of what anatomic location pertains to L1?

Answer 36

Between the inguinal ligament and the medial anterior thigh.

Question 37

Sensation of what anatomic location pertains to L2?

Answer 37

Medial anterior thigh.

Question 38

Sensation of what anatomic location pertains to L3?

Answer 38

Medial anterior knee.

Question 39

Sensation of what anatomic location pertains to L4?

Answer 39

Medial malleolus.

Question 40

Sensation of what anatomic location pertains to L5?

Answer 40

Web space between the 1st and 2nd toes.

Question 41

Sensation of what anatomic location pertains to S1?

Answer 41

Lateral heel.

Question 42

Sensation of what anatomic location pertains to S2?

Answer 42

Lateral popliteal fossa.

Question 43

Sensation of what anatomic location pertains to S3?

Answer 43

Ischial tuberosity.

Question 44

Sensation of what anatomic location pertains to S4-S5?

Answer 44

Anus.

Question 45

How is sensation scored in SCI?
What must you remember when scoring PP (pin prick)?

Answer 45

Sensory levels are scored as 0 (absent), 1 (impaired, including hyper-esthesia), 2 (normal), or not testable (NT).

When scoring PP, inability to distinguish PP from LT is scored 0/2.

Question 46

How is muscle strength scored in SCI?

Answer 46

Muscles are graded from 0 (total paralysis) to 5 (normal active movement with full ROM against full resistance), or NT.

Question 47

Describe the ASIA impairment scale from A to E.

Answer 47

A Complete – No sensory or motor function is preserved in the lowest sacral segments S4-5. The ZPP (only used in ASIA A) refers to the most caudal segment below the level of injury with partial sensory or motor function.

B Incomplete – Sensory but no motor function is preserved below the neurologic level and must include sacral segments S4-5.

C Incomplete – Motor function is preserved more than three levels below the neurologic level, and more than half of the key muscles below the neurologic level have a muscle grade 3.

D Incomplete – Motor function is preserved more than three levels below the neurologic level, and at least half of the key muscles below the neurologic level have a muscle grade ≥3.

E Normal – LT, PP, and motor function of the key muscles are normal.4

Note: For an individual to receive a grade of ASIA C or D, there must be sensory or motor S4-5 sparing. In addition, the individual must have either (1) voluntary anal sphincter contraction or (2) sparing of motor function more than three levels below the motor level.

Question 48

What is Central Cord Syndrome?
CCS is seen in what population group?
What is the postulated mechanism of injury in CCS?

Answer 48

Central Cord – This incomplete syndrome is typically seen in older persons with cervical spondylosis who experience neck hyperextension injury, resulting in greater upper limb rather than lower limb impairment.

Bowel, bladder, and sexual dysfunction are variable.

The postulated mechanism of injury involves cord compression both anteriorly and posteriorly, with inward bulging of the ligamentum flavum during hyperextension in a stenotic spinal canal.

Question 49

What is Brown-Séquard Syndrome?
Describe the pattern of weakness and sensory impairment in BSS.

Answer 49

Brown-Séquard – Hemisection of the cord produces ipsilateral weakness and proprioceptive loss and contralateral loss of PP and temperature sense. The prognosis for ambulation is best among the incomplete SCI syndromes.

Question 50

What is Anterior Cord Syndrome?
Describe the pattern of weakness and sensory impairment in BSS.
Name 1 cause of ACS.

Answer 50

Anterior Cord – There is variable loss of motor and PP sensation, with relative preservation of proprioception and LT.

Prognosis for motor recovery is generally considered poor.

Typically, the anterior cord syndrome results from a vascular lesion in the territory of the anterior spinal artery, but it may also be seen resulting from retropulsed disks/ vertebral fragments. Intraoperative SSEPs, which primarily monitor the posterior column pathways, may miss the development of an anterior cord syndrome.

Question 51

Cauda Equina injuries result from compression or FX to what part of the spine?
What 3 functions are impaired?
What type of pain is associated with Cauda Equina Syndrome?

Answer 51

Cauda Equina – Cauda equina injuries may be due to neural canal compression or fractures of the sacrum or spine at L2 or below.

While the damage occurs within the spinal cord, the syndrome can be described as “multiple lumbosacral radiculopathies,” since the cauda is comprised of lumbosacral nerve roots. Sequelae depend on the roots involved but usually involve impairment of bowel, bladder, and sexual function.
Areflexia, saddle anesthesia, and lower limb weakness are also characteristic. Radicular neuropathic pain is common and can be severe. Recovery is possible because the nerve roots can recover. Consultation for possible early surgery is indicated.

Question 52

Describe the symptoms of a pure Conus Medullaris lesion. What part of the spine is involved? Contrast this to Cauda Equina Syndrome.
What 2 reflexes may be preserved?

Answer 52

Conus Medullaris – A pure conus medullaris lesion (e.g., intramedullary tumor) results in saddle anesthesia and bladder, sphincter, and sexual dysfunction due to cord injury at the S2-4 segments. (VS. L2 or below for Cauda Equina)

Anal cutaneous and bulbocavernosus (S2-4) and ankle deep tendon reflexes (S1,S2) may be either absent or preserved depending upon whether the lesion is “high” in the conus. Prognosis for recovery is poor. Conus lesions due to trauma (e.g., L1 vertebral body fracture) are typically accompanied by injury of some of the lumbosacral nerve roots, resulting in a variable degree of lower limb dysfunction.

Question 53

Name 1 neuroprotective treatment for SCI.

Answer 53

High dose steroids.

Question 54

In terms of recovery in complete SCI, when do most upper limb recovery occur? Which recovers faster, motor or sensory?

Answer 54

Most upper limb recovery occurs during the first 6 months, with the greatest rate of change during the first 3 months. Motor level is superior to the neurologic or sensory level in correlating with function.

Question 55

In incomplete SCI, preservation of “what” is predictive of eventual functional ambulation?

Answer 55

partial (or greater) preservation of PP sensation below the zone of injury was predictive of eventual functional ambulation.

Question 56

How many hours post-SCI, should the neurological examination be performed? Why?

Answer 56

The 72-hour post-SCI neurologic examination may predict recovery more reliably than an examination performed on the day of injury.

Question 57

What does absence of the bulbocavernosus reflex signify? (what type of lesion)

Answer 57

Absence of the bulbocavernosus reflex beyond the first few days can signify a lower motor neuron lesion and have implications on bowel, bladder, and sexual function.

Question 58

What findings on MRI are negative predictors of motor function at 1 year?

Answer 58

On MRI, presence of hemorrhage and length of edema are independent negative predictors of motor function at 1 year. Strength ≥3/5 in the b/l HFs and one KE correlates with community ambulation.

Question 59

Describe the expected functional levels of C1-3

Answer 59

C1-3 – ventilator dependent (or may have phrenic nerve pacing); D for secretion management. I with power WC mobility and pressure relief with equipment; otherwise essentially D for all care (but I for directing care).

(I, independent; A, assist; D, dependent; predicted outcomes are based on patients of typical age for traumatic SCI – older patients have overall poorer expected outcome)

Question 60

Describe the expected functional levels of C4

Answer 60

C4 – may be able to breathe w/o a ventilator. May use a mobile arm support for limited ADLs if there is some elbow flexion and deltoid strength. May be able to use a sip–puff or head-control WC.

(I, independent; A, assist; D, dependent; predicted outcomes are based on patients of typical age for traumatic SCI – older patients have overall poorer expected outcome)

Question 61

Describe the expected functional levels of C5

Answer 61

C5 – may require A to clear secretions. May be I for feeding after setup and with adaptive equipment, e.g., a long opponens orthosis with utensil slots and mobile arm support. Requires A for most upper body ADLs. Most patients will be unable to do self–clean intermittent catheterization. I with power WC; some users may be I with manual WC on noncarpeted, level, indoor surfaces. Some may drive specially adapted vans.

(I, independent; A, assist; D, dependent; predicted outcomes are based on patients of typical age for traumatic SCI – older patients have overall poorer expected outcome)

Question 62

Describe the expected functional levels of C6

Answer 62

C6 – May use a tenodesis orthosis and short opponens orthosis with utensil slots. I with feeding except for cutting food. I for most upper body ADLs after setup and with modifications (e.g., Velcro straps on clothing); A to D for most lower body ADLs, including bowel care. Some males may be I with self–intermittent catheterization (IC) after setup; females are usually D. Some patients may be I for transfers using a sliding board and heel loops, but many will require A. May be I with manual WC, but power WCs are often used, especially for longer distances and outdoors. May drive an adapted van.

(I, independent; A, assist; D, dependent; predicted outcomes are based on patients of typical age for traumatic SCI – older patients have overall poorer expected outcome)

Question 63

Describe the expected functional levels of C7

Answer 63

C7 – Essentially I for most ADLs, often using a short opponens splint and universal cuff. May require A for some lower body ADLs. Women may have difficulty with IC. Bowel care may be I with adaptive equipment, but suppository insertion may still be difficult. I for mobility at a manual WC level, except for uneven transfers. Patients may be I with a nonvan automobile with hand controls if the patient can transfer and load/ unload the WC.

(I, independent; A, assist; D, dependent; predicted outcomes are based on patients of typical age for traumatic SCI – older patients have overall poorer expected outcome)

Question 64

Describe the expected functional levels of C8

Answer 64

C8 – Completely I with ADLs and mobility using manual WC and adapted car.

(I, independent; A, assist; D, dependent; predicted outcomes are based on patients of typical age for traumatic SCI – older patients have overall poorer expected outcome)

Question 65

Describe the expected functional levels of Paraplegia.

Answer 65

Paraplegia – Trunk stability improves with lower lesions. Upper and midthoracics may stand and ambulate with b/l KAFOs and Lofstrand crutches (i.e., swing-through or swing-to gait), but the intent is usually exercise, not functional mobility. Using orthoses and gait-assistive devices, lower thoracics and L1 SCI patients can do household ambulation and may be I community ambulators. L2-S5 SCI patients may be community ambulators with or w/o orthoses (i.e., KAFOs or AFOs) and/or gait-assistive devices. (AFOs generally compensate for the ankle weakness, while canes and crutches primarily compensate for hip abduction and extension weakness.)

Question 66

What is Autonomic Dysreflexia (AD)?
What SCI level of injury predisposes the SCI patient to AD?
What clinical presentation indicates Autonomic Dysreflexia (AD)?
Name 2 causes of Autonomic Dysreflexia (AD) in SCI.
What is the TX of Autonomic Dysreflexia (AD) in SCI?

Answer 66

Autonomic Dysreflexia (AD) – can occur up to 85% of patients with SCI at T6 or above.
Since resting SBPs can be 90 to 110 mm Hg in this population, SBPs of 20 to 40 mm Hg > baseline may signify AD.
A noxious stimulus below the level of injury causes reflex sympathetic vasoconstriction (BP ↑).
Due to the SCI, higher CNS centers cannot directly modulate the sympathetic response. The body attempts to lower BP by carotid and aortic baroreceptor/vagal-mediated bradycardia, but this is usually ineffective.

The primary treatment of AD entails removing the source of noxious stimulus. This is most commonly bladder dysfunction, and the second most common cause is bowel distention. Other causes include pressure ulcers, undiagnosed fractures, abdominal emergencies, ingrown toenails, and body positioning.

Question 67

Describe Long-Term Routine Urinary Tract Surveillance after SCI.
Describe for both upper tract and lower tract.
What test should be done if a SCI patient has 10 years of chronic indwelling?

Answer 67

Upper tract follow-up can include renal scan with GFR or renal scan with 24-hour Cr clearance yearly to follow renal function. Renal and bladder ultrasound can be done annually to detect hydronephrosis and stones.

Lower tract evaluation can include urodynamics once the bladder starts exhibiting uninhibited contractions (or at around 3 to 6 months postinjury) and then as determined by the clinician (often done annually).

Routine cystoscopy to potentially diagnose neoplasm at an earlier rather than a later stage should be performed annually as patients approach 10 years of chronic indwelling (urethral or suprapubic) catheter use or sooner (after 5 years) if there are additional risk factors (heavy smoker, age > 40 years, and history of many UTIs).

Question 68

What is Posttraumatic Syringomyelia?
Describe the clinical presentation of Posttraumatic Syringomyelia.
How is Posttraumatic Syringomyelia diagnosed?

Answer 68

Posttraumatic Syringomyelia – seen in ≈3% to 8% of posttraumatic SCI patients as manifested by neurologic decline or up to 20% on autopsy. It can develop as early as 2 months post-SCI.
Pain is often worsened by coughing or straining, but not by lying supine.
Ascending sensory loss, progressive weakness (including bulbar muscles), ↑ sweating, orthostasis, and Horner’s syndrome may also be seen.
Diagnosis is by MRI.
Treatment is usually observational and symptomatic. Surgical interventions are available for large, progressive lesions.

Question 69

Describe Sexual Function and Fertility in female SCI patients
What TX is recommended during delivery in female SCI? Describe the SCI level. Why is this TX given?

Answer 69

Females: 44% to 55% of women with SCI can achieve orgasm. Menses typically returns within 6 months post-SCI, and reproductive function is preserved. Incidence of prematurity and small-for-date infants is high, but there is no increase in spontaneous abortions.

Spinal anesthesia is recommended during delivery for patients with SCI at T6 or above to avoid AD.

Question 70

Describe Sexual Function and Fertility in male SCI patients.
Injury to what SCI level results in erections of poor quality and duration?

Answer 70

Males: With complete upper motor neuron SCI, reflexogenic erections can usually be achieved, although ejaculation is rare.

With incomplete SCI, reflexogenic erections are usually attainable; ejaculation is less rare than for those with complete SCI; and some patients can achieve psychogenic erections.

Complete or incomplete injuries below T11 may result in erections of poor quality and duration. Infertility is common after SCI, due to factors including retrograde ejaculation and poor sperm quantity and motility.
Vibratory ejaculation in which the ventral penile shaft is stimulated requires that the postinjury period is >6 months and L2-S1 is intact.
Electroejaculation (seminal vesicle and prostatic stimulation through the rectum) is another option.

Question 71

Regarding Tendon Transfer Surgery in Tetraplegia
How can triceps function be restored in C5,6 SCI?
How can Lateral key grip be restored in C6 SCI? Name and describe the procedure.

Answer 71

Triceps function can be restored in the C5,6 SCI patient with a posterior deltoid-to-triceps or a biceps-totriceps transfer.

Lateral key grip can be restored in a C6 SCI patient via the modified Moberg procedure, which involves attachment of the brachioradialis (C5,6) to the flexor pollicis longus (C8,T1) and stabilization of the thumb carpometacarpal and IP joints.