Dear Professor Friedland
Following cancer treatments, I now have peripheral neuropathy that renders the finger tips with very minimal feeling. I need suggestiions for easier covering of tone holes in clarinet.
First off, I think you are being courageous to play the clarinet after this kind of devastation. I know that we will all cheer you on in your quest to get closer to feeling your clarinet.
This is no easy problem you are talking about.
Minimal feeling can be assisted by something on your fingers which will stick to the keys, and when used repeatedly. some kind of adhesive as simple as it may sound may help you. And, it is simple to manufacture.
We have two grand daughters who are currenly into putting little stickers on virtually everything they own.
This may be in some elliptical way, a help to you. also double-sided tape or even that airplane glue which we use frequently and dries to a sticky surface which will pull almost in a sheet, when dry.While it is sticky, it may give you more purchase on the keys.
I know that I would go as far as to attempt to adhere fingers to keys and tone holes in any way of which I can think,with any kind of substance.
Let us stop for a moment to examine peripheral neuropathy in a somewhat scientific manner.
Various causes are covered in the following, taken from Wikipedia
“Neuropathy” redirects here. For other uses, see Neuropathy (disambiguation).
Not to be confused with Nephropathy.
Classification and external resources
ICD-10 G64., G90.0
ICD-9 356.0, 356.8
Peripheral neuropathy is the term for damage to nerves of the peripheral nervous system, which may be caused either by diseases of the nerve or from the side-effectsof systemic illness.
The four cardinal patterns of peripheral neuropathy are polyneuropathy, mononeuropathy, mononeuritis multiplex and autonomic neuropathy. The most common form is (symmetrical) peripheral polyneuropathy, which mainly affects the feet and legs. The form of neuropathy may be further broken down by cause, or the size of predominant fiber involvement, i.e., large fiber or small fiber peripheral neuropathy. Frequently the cause of a neuropathy cannot be identified and it is designated idiopathic.
Neuropathy may be associated with varying combinations of weakness, autonomic changes, and sensory changes. Loss of muscle bulk or fasciculations, a particular fine twitching of muscle, may be seen. Sensory symptoms encompass loss of sensation and “positive” phenomena including pain. Symptoms depend on the type of nerves affected (motor, sensory, or autonomic) and where the nerves are located in the body. One or more types of nerves may be affected. Common symptoms associated with damage to the motor nerve are muscle weakness, cramps, and spasms. Loss of balance and coordination may also occur. Damage to the sensory nerve can produce tingling, numbness, and pain. Pain associated with this nerve is described in various ways such as the following: sensation of wearing an invisible “glove” or “sock”, burning, freezing, or electric-like, extreme sensitivity to touch. The autonomic nerve damage causes problems with involuntary functions leading to symptoms such as abnormal blood pressure and heart rate, reduced ability to perspire, constipation.
Many treatment strategies for peripheral neuropathy are symptomatic. Some current research in animal models has shown that neurotrophin-3 can oppose the demyelination present in some peripheral neuropathies.
A range of drugs that act on the central nervous system such as drugs originally intended as antidepressants and antiepileptic drugs have been found to be useful in managing neuropathic pain. Commonly used treatments include using a tricyclic antidepressant (such as amitriptyline) and antiepileptic therapies such as gabapentin or sodium valproate. These have the advantage that besides being effective in many cases they are relatively low cost.
A great deal of research has been done between 2005 and 2010 which indicates that synthetic cannabinoids and inhaled cannabis are effective treatments for a range of neuropathic disorders.  Research has demonstrated that the synthetic oral cannabinoid Nabilone is an effective adjunct treatment option for neuropathic conditions, especially for people who are resistant, intolerant, or allergic to common medications. Orally, opiate derivatives were found to be more effective than cannabis for most people. Smoked cannabis has been found to provide relief from HIV-associated sensory neuropathy.  Smoked cannabis was also found to relieve neuropathy associated with CRPS type I, spinal cord injury, peripheral neuropathy, and nerve injury. 
Pregabalin (INN, pronounced /prɨˈɡæbəlɨn/) is an anticonvulsant drug used for neuropathic pain. It has also been found effective for generalized anxiety disorder. It was designed as a more potent successor to gabapentin but is significantly more expensive, especially now the patent on gabapentin has expired and gabapentin is available as a generic drug. Pregabalin is marketed by Pfizer under the trade name Lyrica.
Lyrica has been of considerable assistance in relieving fibromyalgia, recently formally recognized as an actual illness.
TENS (Transcutaneous Electrical Nerve Stimulation) therapy may be effective and safe in the treatment of diabetic peripheral neuropathy. A recent review of three trials involving 78 patients found some improvement in pain scores after 4 and 6 but not 12 weeks of treatment, and an overall improvement in neuropathic symptoms at 12 weeks. A second review of four trials found significant improvement in pain and overall symptoms, with 38% of patients in one trial becoming asymptomatic. The treatment remains effective even after prolonged use, but symptoms return to baseline within a month of treatment cessation.
I am sure that certainly your particular cause may be covered in the above, however as a clarinetist and (certainly not a doctor) I can only make suggestions which may seem terribly ordinary or even childish.
I like and have tried the tricyclic antidepressant, amitriptyline, which is called Elavil. And certainly the idea of cannabis as a possible treatment is quite interesting, even appealing. This drug has healing and restorative possibilities beyond all imagination, and certainly may help you in feeling the keys, the tone holes and in playing the clarinet.
Certainly, I hope that I have helped you in some small way, and again, I cheer you on in working on solving this problem.
I received this commentary from Dr. Danny Silver, and it certainly a good idea, especially as Dr Silver says, if he can maintainpressure on the plateau keys.
This unfortunate fellow most probably has developed peripheral neuropathy from the drugs used for chemotherapy to treat his cancer. He may have partial relief or hopefully complete relief of his symptoms – altered sensation or pain in his hands and feet over time and the agents you’ve mentioned may or may not be helpful – only time will tell. I think that he might find a plateau clarinet useful as he would then be reasonably certain of complete closure of tone holes assuming he has applied pressure to the plateau keys.
Best wishes, Dr Danny Silver