Romberg Test
Normally one can stand upright either:
-with vision eliminated (eg, with eye closed)
-with proprioception disrupted (eg, standing on a moving or tilting surface)
-with vestibular function distorted (eg, as a result of rotationally induced vertigo).

The postural reactions initiated by vestibulospinal reflexes are opposite to the direction of vertigo. 
Loss or distortion of inputs from two or more systems is typically associated with disequilibrium and falls.A patient with profound loss of proprioception, or with uncompensated unilateral or bilateral vestibular dysfunction, may fall if vision is eliminated (eg, with eyes closed). This is the basis of the Romberg sign.
In aging, the impaired information from the somatosensory and vestibular systems may make visual information particularly relevant (a “preferred” input). Aging is accompanied by an increased Romberg’s quotient, which indicates that a greater reliance is being placed on visual information: the Romberg Quotient (RQ), is calculated from the ratio between  postural stability with the eyes open and closed¹.
 

Patients should be able to:

1. Walk and turn without stumbling
2. Past point accurately

Evidence of static imbalance in vestibulospinal reflexes:

1. Romberg test 
2. Tandem walking with eyes open and closed 
3. March in place without significant postural drift over 30 to 60 seconds with eyes closed²

Dynamic vestibulospinal function can be assessed by observing postural stability during rapid turns or in response to external perturbations imposed by the examiner, for example, by giving the patient a gentle push forwards, backwards or sideways².

WALKING

Unilateral vestibular lesions result in turning in the direction of pastpointing and falling towards the side of the lesion (in the direction of the slow component of nystagmus).

ROMBERG TEST

The examiner observes postural stability with the patient placing their feet together, initially with eyes open and then with the eyes closed. Most normal subjects under the age of 70 can stand in this position for 30 seconds³.

The Romberg test is termed positive when a patient is able to stand with feet together and eyes open, but sways or falls with eyes closed. However, although the Romberg sign is now fairly standardized, there is variability in examination technique and interpretation across expert examiners, which affects both the sensitivity and specificity of the test for determining dysfunction⁴. 
In particular, there is variability in:

1. How much postural instability is required for a positive test (eg, increased sway only, a step to the side, or a fall)
2. Whether sway at the ankles is critical or whether sway from the hips can be accepted.
3. Whether the feet should be positioned together, as close together as possible to maintain stance with eyes open, or in tandem position.
4. Whether footwear should be worn or removed.
5. Whether hands should be held at the side or extended forward or laterally

Sensitivity of the Romberg test can be increased by:
-narrowing the patient’s base of support (sometimes called a “sharpened Romberg test” or a "modified Romberg test" with the feet in a heel-to-toe position) 
-standing on foam rubber to distort proprioceptive input from the feet. This is termed the Clinical Test of Sensory Interaction and Balance⁵

-Findings
 Falling or tilting to the side opposite to the direction of the fast phase of nystagmus (ie, toward the side of the lesion) is a characteristic finding in a peripheral vestibular disorder. 

Condition 4=standing on foam with eyes open; 
Condition5 =standing on foam with eyes closed.
Three trials reported for each condition. Patients wore socks or stockings and stood with their feet together.
Trials terminated when the subject's arms or feet changed position.

From: Cohen H, Blatchly CA, Gombash LL. A study of the clinical test of sensory interaction and balance. Phys Ther. 1993 Jun;73(6):346-51; discussion 351-4. 

*Standard deviations shown in parentheses
Group 1= asymptomatic subjects (n=15) aged 25 to 44 years
Group 2=asymptomatic subjects (n=15) aged 45 to 64 years
Group 3=asymptomatic subjects (n=15) aged 65 to 84 years
Group 4=vestibularly impaired subjects (n = 17).
 

Causes

• Bilateral vestibular loss
• Acute unilateral vestibular loss
• Lesions of the spinocerebellum (the anterior vermis and paravermis of the anterior lobe), and less often with other cerebellar dysfunction.
• Static imbalance in otolith-spinal reflexes also leads to excessive sway (e.g. lateral head and body tilt with utriculospinal imbalance) and sideways deviation on the stepping tests².

The test is insensitive for detecting chronic unilateral vestibular impairment, although foam posturography is sensitive for acute and chronic unilateral and bilateral vestibular dysfunction (Figure 1, Group 4).

(vv)Foam.mp4(tt)


From: Halmagyi GM. Clinical Examination of the Vestibular System. J Vestib Res. Teaching Course, 29th Bárány Society Meeting, Lecture 2, June 5, 2016, Seoul, Korea.
From: https://www.youtube.com/watch?v=ehR7SOlBBow
 

TANDEM GAIT

When performed with eyes open, tandem walking is primarily a test of cerebellar function, because vision compensates for chronic vestibular and proprioceptive deficits. However, acute vestibular lesions typically impair tandem walking, eve.n with the eyes open⁴.
Tandem walking may be examined with eyes open and then closed.

MARCH/STEPPING TESTS

The stepping test is the equivalent for the legs of testing past pointing in the arms. Stepping tests include the Unterberger/Fukuda tests which assess the degree of postural drift,  which is a sensitive indicator of vestibulospinal function. 

The patients is asked to march on the spot for 30 seconds with eyes closed,
Marching/stepping tests may be more sensitive indicators of balance dysfunction and presence of nystagmus than the Romberg test⁶.

-Findings
 An imbalance is reflected in excessive turning to the side of the lesion^2,4.

(vv)Fukuda.mp4(tt)

From: Halmagyi GM. Clinical Examination of the Vestibular System. J Vestib Res. Teaching Course, 29th Bárány Society Meeting, Lecture 2, June 5, 2016, Seoul, Korea.
From: https://www.youtube.com/watch?v=ehR7SOlBBow
 

PAST-POINTING

Past-pointing is a clear indication of tonic imbalance of the vestibular system.

The patient should be seated in order to reduce conflicting information from other physiological sources.  For the arms, past-pointing is best elicited by having the patient repetitively raise an arm over the head with the index fingers extended, and then bring the arm down, with eyes closed, towards the examiner’s index finger (but without touching it), located at waist level².
Note that the standard finger-to-nose test will not identify pastpointing, since joint and muscle proprioceptive signals permit accurate localization even when vestibular tone is asymmetric

-Findings
 Patients with past-pointing due to acute vestibular dysfunction point towards the lesioned side, which is the side to which postural drift will occur.
 There is reportedly a large degree of variability in the test, partly due to rapid compensation occurring⁴.

-Causes
 Acute vestibular disease
 The past pointing test is insensitive for detecting chronic unilateral vestibular impairment.