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A 31 year old French hornist was referred for evaluation of a 9 month history of pain in her right upper lip.
A member of a major symphonic orchestra, she regularly played 4–6 hours a day. Her symptoms began after a heavy period of playing, with a sensation of excess pressure in the right upper lip followed shortly thereafter by frank pain in this area. She spontaneously distinguished between two types of pain. The first was a constant dull ache, extending from the midline 1cm laterally onto the vermilion lip. She noticed that brushing her teeth or eating could trigger pain in this region. Her second pain sensation was different from the first—electric, lancinating pain originating in the medial portion of the right lip and extending to her right nostril. There were no paraesthesias of the lips, cheeks, or jaw, and she had no symptoms of facial weakness.
She compensated for her difficulties and maintained her usual high level of professional performance. Briefs periods of rest produced temporary improvement; however, her symptoms recurred when she resumed performing. There were no other complaints and her family history and medical history were unremarkable.
Except for her right lip, neurological examination was normal including careful sensory evaluation of the anterior teeth, gums, and palate. Her right first incisor was noted to protrude slightly in front of her left. As shown in the figure, light touch sensibility was reduced in the right lip (wide cross hatching). A smaller region (narrow cross hatching) was painful to touch, lying directly over her prominent first incisor and below the contact point for the circular mouthpiece of the horn (fine stippling). Application of viscous lidocaine to the lip temporarily relieved her symptoms. An MRI of the head was obtained, showing no abnormalities along the path of the trigeminal nerve. A brief course of gabapentin at 900 mg/day was ineffective, and she declined further drug treatment. Filing down her prominent right first incisor in combination with 6 weeks of complete rest produced marked improvement in her symptoms. Her sensory loss improved as well, and she was able to return to work.
Musicians who play brass instruments (trumpet, French horn, trombone, and tuba) spend their professional lives perfecting control of the embouchure, the muscles of the lower face, lips, and tongue that control the direction and intensity of airflow into the mouthpiece. The lips and face of a brass player experience tremendous pressure from the mouthpiece, sometimes sufficient to cause muscle strains or even traumatic tears in the orbicularis oris.1
This patient's sensory disturbance localised to the anterior superior alveolar nerve.The superior alveolar nerve divides into a posterior, middle, and anterior group. Branches from these divisions form a plexus that innervates the dental pulp, periodontal membrane, adjacent labial and buccal gingiva, and the upper teeth. The posterior, middle, and anterior branches innervate the molar, premolar, and incisor or canine teeth, respectively. Only the anterior superior alveolar nerve travels with the infraorbital nerve to exit through the infraorbital foramen.2 In our patient, her prominent right first incisor predisposed a terminal branch of this nerve to focal entrapment by the overlying mouthpiece rim.
Injuries related to occupation are increasingly recognised among performing artists. Focal entrapment neuropathies of the arm have been well described in musicians. This patient shows that similar occupational neuropathies may affect the lips and face. We are aware of two other reports of patients similar to ours.3 4 Given that the force exerted on the lips by the mouthpiece of a French horn has been measured to be as high as 50 N, with displacements of the central incisors of up to 180 μm during playing, it is not surprising that these neuropathies occur5.
French horn and trumpet mouthpieces are significantly smaller than those of the trombone and tuba, and so mouthpiece forces are concentrated onto a very small lip surface area. We suspect that there are other French horn and trumpet players who have experienced similar symptoms to our patient.
Entrapment neuropathy is a potentially reversible cause of disability in brass players, and should be considered in the differential diagnosis of embouchure dysfunction.
I thank Drs Jonathan Aviv, and Michael Gelb, for their assistance in caring for the patient.