Student's Corner

Osteopathic manipulative treatmentof Bell's palsy

by Robert F.Ulrich, MS-Ill, University of North Texas Health Sciences at Fort Worth/TCOM

IntroductionBell's palsy is defined as paralysis

or weakness of the muscles suppliedby the facial nerve (CN VII) due toinflammation and swelling of thenerve within the facial canal. It isalmost always unilateral, mostcommon in people over the age ofthirty, and affects approximately 1 in65 people over the course of a lifetime.A diagnosis of Bell's palsy implies anidiopathic cause, but antecedentfactors include exposure to cold orviruses, and head trauma. Associateddiseases include the Ramsay Huntsyndrome, which is Bell's palsy alongwith vesicles in the external auditorycanal or behind the auricle and is dueto herpes zoster infection of thegeniculate ganglion. Bilateral facialparalysis is highly unusual and shouldprompt a search for conditions suchas Guillian-Barre syndrome orchronicmeningitis.

Clinical ManifestationsOnset of Bell's palsy is fairly

abrupt, occurring suddenly or over afew days with maximum weaknessusually attained by 48 hours. Painbehind the ear may precede paralysisby a day or two. CN VII supj lies allmuscles of facial expression and thisis manifested clinically by droopingof the corner of the mouth, flatteningof skin creases and folds of the faceand forehead, inability to close theeyelid on the affected side, and

sagging of the lower lid which allowsthe punctum to fall away from theconjunctiva, resulting in tearing. Thesite of the lesion determines the clinicalpresentation, so it is necessary to focuson the anatomy of the facial nerve.

AnatomyCN VII is primarily motor,

supplying the muscles of facialexpression and muscles of the scalp,auricle, buccinator, platysma,stapedius, stylohyoid, and the posteriorbelly of the digastric. It has a smallsensory component (nervusintermedius) which conveys tastesensation from the anterior two-thirdsof the tongue and cutaneous sensationfrom the anterior wall of the externalauditory canal. It also suppliesparasympathetic secretory stimulus tothe submandibular, sublingual, andlacrimal glands. The facial nerveoriginates in the pons, where the motornucleus is located. Upon leaving thepons it enters the internal auditorymeatus with the acoustic nerve. Itcourses through the middle ear in thetemporal bone where it gives off asmall branch, the nerve to the stapedius,which performs a dampening function.The nerve exits the skull at thestylomastoid foramen, passes throughthe parotid gland and subdivides intofive branches to provide the facialmuscles.

If the lesion is at the stylomastoidforamen, only the muscles of facial

expression are affected. If the lesion isin the middle ear portion, taste is lostover the ipsilateral anterior two-thirdsof the tongue. If the nerve to thestapedius is interrupted, the patientexperiences hyperacusis (painfulsensitivity to loud sounds) and mayexperience unilateral ear pain. Lesionsin the internal auditory meatus canalso affect adjacent auditory andvestibular nerves causing deafness,tinnitus, or dizziness.

Case PresentationThe patient is a 39-year-old white

female who initially presented to thecore clinic in March 1997, with a chiefcomplaint of chronic right ear painwhich she described as a "deep ache."She also complained of a feeling in herright ear "like a broken speaker"approximately once a day, aggravatedby noisy environment; and of rightfacial weakness with right eye irritationwhen she became tired. She stated thatall these symptoms were residual fromhaving Bell's palsy three years ago. Atthe onset of her disease, she visited herfamily doctor and was placed onNSAIDS with no relief of symptoms.She suffered from complete unilateralfacial paralysis for three months, atwhich time she began to graduallyimprove. During this time she alsosuffered from chronic right ear painand "crackling" in her ear whichpersisted until she visited the OMTclinic. Trauma history was significant

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for being knocked unconscious by abaseball as a child without anyevidence of skull fractures. Shedisclosed that she had studied martialarts for a couple of years withnumerous falls. She also reported abad middle-ear infectionapproximately 12 years ago whichresolved with antibiotics. Physicalexamination at the time of her initialvisit to the OMT clinic revealed aslight flattening of facial creases andfolds. Palpation of her skull revealedabsence of motion. She was diagnosedwith sphenobasilar compression andtreated with supine-indirect-inherentforce at the sphenobasilar symphysisand condylar decompression withgood response. Since that time shehas visited the core clinic weekly andstates that her ear problems haveimproved tremendously. She now getsthe "broken speaker" sound and earpain about once a week. The rightside of her face still shows someevidence of crease flattening. On hermost recent visit (April 30, 1997) shereported no ear pain or hearingproblems over the previous week.

TreatmentApproximately 80 percent of cases

recover completely over a period ofweeks to months. Traditional therapyis primarily supportive and consistsof keeping the affected eye patchedand moistened to prevent cornealdrying and abrasions. Medicaltreatment consists of startingPrednisone 80mg po qd for three daysand tapering this by 20mg every threedays. Steroid treatment should beginimmediately – there is little benefit inusing steroids after four days. Oneauthor reports using high-voltageelectrical stimulation of the facialmuscles with successful results.

There is a paucity of literature

regarding osteopathic manipulativetreatment for treatment of Bell's palsy,although much anecdotal evidenceexists. Most documented evidencepoints to an etiology of trauma. Themost common somatic dysfunctionsreported are sphenobasilarcompression and external fixation ofthe temporal bones. Trauma can easilydisrupt the "rocker bearing"mechanism of the temporal jugularsurface on the occipital jugulartubercle, which is in closeapproximation to the facial nerve. Inaddition, any shifts of the temporalbone can cause dural tension at theinternal acoustic meatus. Irritation ofnerve roots can result in histaminerelease, which causes peripheralvasodilation, fluid exudation, andcontinued irritation. Somaticdysfunction of the sphenoid, occiput,and temporal bones; and restrictionof cervical and thoracic myofascialelements inhibit lymphatic drainage.The edema in the unyielding bonycanal results in a pressure neuritiswhich manifests its symptomsdepending on the location of the lesionas described earlier. Although there isno OMT mentioned for specificallytreating Bell's palsy, it is implied thatby restoring cranial motion, treatingany fixed restrictions of cranial bones(particularly the temporals), andimproving lymphatic drainage, thepressure on the facial nerve can bedecreased or eliminated and allow thenerve to function properly.

DiscussionThe origin of the Bell's palsy of the

patient in this study was idiopathic,but likely secondary to the head traumaexperienced as a child. Perhaps, theear infection as a young adultcontributed also. At the time shevisited the OMM clinic her facial

paralysis had largely resolved, but theear pain and dysfunctional hearingcontinued to trouble her daily. Basedupon these symptoms, it is almostcertain that her CN VII was affectedfairly high up in the facial canal. Headtrauma can result in shifts in positionof the occiput and temporal bone,resulting in dural tension, restrictionof physiologic motion, and edema. Inthe limited space of the bony facialcanal, this can lead to ischemia andeventually degeneration fromcompression. This is essentially anentrapment neuropathy. With thecranial treatment this patient received,physiologic motion was restored,tension was relieved from the nerve,and she has obtained complete reliefof her symptoms. Bell's palsy is afairly common condition, one thatpracticing physicians are likely to seeoften. As osteopathic physicians,cranial treatment is an importantmodality that can be used to providerelief to these patients, particularlywhen allopathic methods fail.

BibiliographyI. Disorders of the Cranial Nerves. In:

Harrison's Principles of Internal Medicine.12th edition. Wilson, JD et al, eds. 1991.2078-2079.

2. Magoun, HI. Entrapment Neuropathy ofthe CNS. Part II CN I-V, VI-V111. XII.JAOA 1968, 67: 779-787.

3. Osteopathic Considerations in Diagnosisand Treatment. In: Foundations forOsteopathic Medicine. Ward, RC, ed. 1996,p 530.

4. Practical Application of the CranialConcept. In: Osteopathy in the CranialField. Magoun,HI, ed. 1976, p 269.

5. Shrode, LW. Treatment of Facial MusclesAffected by Bell's Palsy with High-Voltage Electrical Muscle Stimulation. J

Manipulative Phsiol Ther 1993; 16(5):347-352q

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