The left index finger is extremely important to performance on the bassoon, being required simultaneously to provide partial support for the instrument in the left hand while achieving fine movement to produce the rather variable halfhole which is essential to the clarity, pitch, and range of certain notes. The integrity of motor and sensory functions of this finger, which like the entire radial (thumb) side of the palm, the middle finger and part of the ring finger is served by branches of the median nerve of the arm, is fundamental to all hand skills. Impairment of sensation in this part of the hand will cause awkwardness and poor coordination even with fully functional motor nerves, with significant loss of fine control of movement. The thumb, first two fingers, and adjacent portions of the palm which are served by the median nerve have been called "the eyes of the hand" because tactile sensibility in this area is indispensable to all delicate hand adjustments.
Sensation to the index finger is supplied by two small branches of the median nerve which enters the palm near its center at the wrist, promptly dividing into lesser radicles to each side of the thumb, index and middle finger and to the nearer side of the ring finger. The specific branch which concerns us here is the radialis indicis nerve which goes to the thumb side of the index finger, since this is the one which may be pinched in playing the bassoon. The radialis indicis nerve is also accompanied by a small artery, which constitutes about one half of the blood supply of the finger, the two being together in a common loose sheath of connective tissue which is called in toto the neurovascular bundle. The bundle emerges from deep in the hand (becomes superficial and is protected by little more than skin) on the pad at the base of the index finger and continues in this relatively unprotected position along the radial (thumb) side of the finger as far as the last joint. Throughout this length then, from the finger pad to the last joint, this neurovascular bundle is susceptible to damage by pressure.
Where the long joint of the bassoon rests on the left hand the neurovascular bundle may be compressed against the underlying bony structures of the metacarpophalangeal joint (front of the knuckle joint) or the head of the proximal phalanx (first finger bone). Unfortunately, significant pressure against the radial neurovascular bundle of the index finger over a period of time may cause embarrassment to the sensation and circulation which can be very distressing to the bassoonist. The importance of this pressure in causing difficulty will depend on minor individual variations in anatomy, playing position and the specific placement of the left hand, firmness with which left hand posture is held especially when using the thumb, and amount of weight which the left index is allowed to support when playing.
The application of even moderate pressure over a period of time to this superficially situated nerve and artery bundle may lead first to temporary numbness in the finger during the period when its blood supply is actually partially compromised; but as the pressure recurs spasm (local contraction) of the artery and irritation of the nerve may develop for longer periods after the pressure stops. The finger and the nerve become ischemic, that is, the blood flow in them is less than it should be normally. This ischemia (insufficient blood flow) tends to produce scarring, contracture (shortening of connective tissue fibers), and swelling and inflammation of the nerve. The symptoms first caused by early changes will probably be mild swelling, redness or paleness of the finger, or a sensation of "pins and needles' which disappear soon after the bassoon is set down. The symptoms may stop here, or they may progress to frequent or constant pain or aching, "trophic" change with coldness, shiny skin, excessive sensitivity to heat and cold, and lancinating (shooting) pains. It is clear that in any stage of its development this symptom complex is not compatible with optimal bassoon technique.
This problem first came to our attention in the case of a professional bassoonist whose left index finger had reached the stage of trophic change, as a result of which he was substantially unable to perform for nearly a year. This suggested a revision of his whole physical approach to the bassoon, as well as the use of a number of aids. The recovery was complete, and the problem has not recurred. Because of this observation a group of twenty-two bassoonists at a seminar were asked regarding such symptoms; of these, five (notably, all were students) admitted some numbness, coldness, "pins and needles" sensation, or mild pain in the left index. Since that time the writer has observed three symphony bassoonists rubbing the left / forefinger or handling the left hand in a manner that suggested they had discomfort in it. There is no doubt that the syndrome exists, and observations to this point indicate that as many as ten to twenty percent of bassoonists may have some of the symptoms in some degree. It seems unlikely that a more accurate "guesstimate" of its incidence will be possible, since most professional bassoonists would probably be reluctant to admit to it.
Effective management of the difficulty is based on simple mechanical principles which should be appreciated by performers, and especially by teachers. At the first suggestion of difficulty with the left index finger the whole physical approach to the instrument should be studied carefully and evaluated. Specific points of investigation should be:
(1) Is the instrument tilted forward to a degree which places much weight on the left index finger or the pad at its base? It is, not only may the neurovascular bundle be compromised, but facility of execution is also impeded.
(2) Is the instrument grasped too firmly when the left thumb is used? This is not only poor technique, but it will increase the pressure of the bass joint against the vulnerable neurovascular bundle.
(3) Is the hand rotated so that the instrument rests on the thumb side of the left index rather than the palmar surface? It is in this position that the nerve and artery are most likely to be pressed against the underlying bones.
If any of these factors are present, considering ordinary anatomic variation, they may be the cause of the difficulty. Positioning of the hand must then be adjusted so that it is more natural and relaxed when the instrument is used. The second matter to consider is the position of the bassoon with respect to vertical; the more nearly vertical the instrument is held, compatible with good technique, the less weight the left forefinger will be required to support. If the final acceptable angle of the bassoon still appears to place weight at the base of the left index, forward adjustment of the seat strap or the use of a boot pivot with the bassoon against the right thigh will both tend to diminish the weight on the left hand. Still another useful maneuver may be to have the student sit back in the chair and lean on the support (Heaven forbid!). As a last resort a playing stand can relieve the left hand completely of its weight-bearing function.
A last available means of relief is to cement a pad of foam rubber or other soft material on the long joint where the finger supports it. This will spread the weight over a wider area so that there will be no limited pressure point along the course of the neurovascular bundle, for it is a small area of weight-bearing which is ultimately the cause of the injury.
While such adjustments of mechanical nature will probably be the only useful long-term measures, and the symptoms should yield to them over a period of time, it is advisable that bassoonists with this problem should seek medical help. Such measures as medicine can offer, however, would only provide temporary relief, if the basic causes of the problem already discussed were not corrected.
(1) A syndrome characterized by painful left index finger may be seen in perhaps ten to twenty percent of bassoonists.
(2) This syndrome is caused by pressure on the radial neurovascular bundle of the index secondary to the individual manner of addressing the instrument and to the position and amount of tension in the left hand.
(3) Although victims of the difficulty are advised to see a physician it should respond to the simple measures outlined with full functional recovery. Specifically, the position of the left hand should be corrected and weight-bearing by the left hand minimized.
(4) If it reaches the stage of trophic change, the syndrome is quite disabling and can perhaps become permanent.
(The writer wishes to express his thanks to Christopher Weait for his interest in this effort and for presenting the paper, and to Homer C. Pence and Bernard Garfield for their helpful comments.)
Chester w. White, Jr., A.M., M.D. is Associate Anesthesiologist at the Maine Medical center in Portland, Maine. Formerly a tenor saxophonist, he took up the bassoon after his teen-aged son began playing the oboe. He has studied with Homer Pence and is founder of the Maine Woodwind Chamber Players. This paper was read at the Fourth Annual Meeting of the IDRS in Evanston, Ill., in 1975 by Christopher Weait.