Multiple Sclerosis Functional Composite (MSFC)

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Multiple Sclerosis Functional Composite (MSFC)

The MSFC is a three-part, standardized, quantitative, assessment instrument for use in clinical studies, particularly clinical trials, of MS. (Cutter et al, 1999) It was developed by a special Task Force on Clinical Outcomes Assessment that had been appointed by the National Multiple Sclerosis Society’s Advisory Committee on Clinical Trials of New Agents in Multiple Sclerosis. (Whitaker et al, 1995; Rudick et al, 1996) It was the consensus of the task force that important clinical dimensions not emphasized in existing rating scales, e.g. cognition, should be measured. The MSFC was designed to fulfill three criteria:

  1. It should be multidimensional to reflect the varied clinical expression of MS across patients and over time
  2. The dimensions should change relatively independently over time
  3. One component should be a measure of cognitive function. The three components of the MSFC measure leg function/ambulation, arm/hand function, and cognitive function.

Administration Time

Administration time will vary depending upon the ability of the patient. Total administration time for all three measures should be approximately 20-30 minutes.

Administration Method

The MSFC measures are administered in person by a trained examiner. The examiner need not be a physician or nurse.

Scoring

The MSFC can produce scores for each of the three individual measures as well as a composite score. In addition, there are a variety of ways to calculate scores depending on the nature of the study and sample.

General Comments

The three component measures of the MSFC had been used for some time in MS prior to their being combined into a composite measure. Analysis of data from studies using these measures had pointed to their reliability, validity, and sensitivity. As a set of objective, quantitative assessment instruments, the MSFC represents a methodological advance over the ordinal clinical rating scales that have been used in MS in the past, e.g., the EDSS and Ambulation Index. A three-part instrument offering both separate and composite scores, the MSFC provides a versatile assessment method for investigational purposes with the ability to measure patients at various levels of disability, i.e., ambulation at less disabled levels of the EDSS, arm function at more disabled levels, and cognitive function at all levels. Since its introduction, the MSFC has seen increasing use in both clinical trials and other clinical studies.

Psychometric Properties

All three measures making up the MSFC have been shown to have good inter-rater and test-retest reliability. In addition, there is considerable evidence for their validity and sensitivity to clinically relevant change in MS patients. However, performance on the MSFC is sensitive to practice effects, that is, patients often display poorer performance when first tested due to lack of familiarity with the tasks. It is recommended that three or four administrations be given prior to a baseline assessment if accurate (rather than comparative) assessments of change over time are needed. Refer to the discussion of the individual components of the MSFC for further details concerning their psychometric properties.

http://www.nationalmssociety.org/for-professionals/researchers/clinical-study-measures/msfc/index.aspx

Benign Paroxysmal Positional Vertigo

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ICD 9

Benign paroxysmal positional vertigo is a disorder caused by problems in the inner ear. Its symptoms are repeated episodes of positional vertigo, that is, of a spinning sensation caused by changes in head position.

Dizziness accounts for about 6 million clinic visits in the U.S. every year, and 17–42% of these patients eventually are diagnosed with BPPV.

Within the labyrinth of the inner ear lie collections of calcium crystals known as otoconia. In patients with BPPV, the otoconia are dislodged from their usual position within the utricle and they migrate over time into one of the semicircular canals (the posterior canal is most commonly affected due to its anatomical position). When the head is reoriented relative to gravity, the gravity-dependent movement of the heavier otoconial debris within the affected semicircular canal causes abnormal (pathological) fluid endolymph displacement and a resultant sensation of vertigo. This more common condition is known as canalithiasis. In rare cases, the crystals themselves can adhere to a semicircular canal cupula rendering it heavier than the surrounding endolymph. Upon reorientation of the head relative to gravity, the cupula is weighted down by the dense particles thereby inducing an immediate and maintained excitation of semicircular canal afferent nerves. This condition is termed cupulolithiasis.

It can be triggered by any action which stimulates the posterior semi-circular canal which may include tilting the head, rolling over in bed, ooking up or under or sudden head motions.

The condition is diagnosed from patient history (feeling of vertigo with sudden changes in positions); and by performing the Dix-Hallpike maneuver or Horizontal Roll Test which are diagnostic for the condition. The test involves a reorientation of the head to align the canal with the direction of gravity. This test stimulus is effective in provoking the symptoms in subjects suffering from archetypal BPPV. These symptoms are typically a short lived vertigo, and observed nystagmus. If symptoms do not resolves within 8-10 seconds, this is a positive test for cupulolithiasis (symptoms typically are delated and last more than a minute).

The most effective treatments for relieving symptoms of BPPV include the Epley Maneuver (for anterior and posterior canalithiasis/cupulolithiasis), or the Appiani Maneuver (less common include the BBQ Roll and the Brandt-Daroff) (for horizontal canalithiasis/cupulolithiasis). The Epley and Appiani employ gravity to move the calcium build-up that causes the condition. This particle repositioning maneuver can be performed during a clinic visit by specially trained physical therapists. The maneuver is relatively simple but few general health practitioners know how to perform it. The Epley maneuver does not address the actual presence of the particles (otoconia), rather it changes their location. The maneuver moves these particles from areas in the inner ear which cause symptoms, such as vertigo, and repositions them into areas where they do not cause these problems.

Dix Hallpike (tests for anterior and posterior canalithiasis)
Horizontal Roll Test (tests for horizontal canalithiasis)
Epley Manuver (anterior and posterior canal BPPV)
Appiani Maneuver (horizontal canal BPPV)
BPPV PT Treatment Flowsheet
Vestibular Anatomy.

Meclizine is a commonly prescribed medication, but is ultimately ineffective for this condition, other than masking the dizziness. Other sedative medications help mask the symptoms associated with BPPV but do not affect the disease process or resolution rate. Betahistine (trade name Serc) is available in some countries and is commonly prescribed but again it is likely ineffective. Particle repositioning remains the current gold standard treatment for most cases of BPPV.

Surgical treatments, such as a semi-circular canal occlusion, do exist for BPPV but carry the same risk as any neurosurgical procedure. Surgery is reserved for severe and persistent cases which fail particle repositioning and medical therapy.

Supporting Research

Clinical practice guideline: Benign paroxysmal positional vertigo

Benign Paroxysmal Positional Vertigo – contains excellent diagrams of maneuvers

Dizziness and Balance – website with lots of excellent information.