Should I proceed with CTS release surgery on my second hand?


Firstly, thank you for providing this website and support forum. I have read through the content in detail and tried to absorb and interpret the information, in obtaining a better understanding of my CTS condition and trying to establish the best way forward.

My situation is that 10 weeks ago I had release surgery in response to severe carpal and cubital tunnel syndrome on my left (non-dominant) side. NCS test results also indicate I have mild carpal tunnel syndrome and mild ulnar neuropathy at elbow on my right (dominant) side.

I now need to decide whether to proceed with proposed carpal and cubital tunnel release surgery on my right side, even though nerve impairment is believed to only be mild at present. I would be very grateful to receive opinion/advice that may help me in deciding whether it is best to proceed with surgery now, or alternatively monitor my condition for further signs of deterioration before proceeding.

The background to my case and subsequent surgery is as follows:-

Following clinical assessment and a subsequent NCS six months ago, I was diagnosed to have severe carpal tunnel syndrome and severe ulnar neuropathy on my left (non dominant) hand/arm.

Prior to this, I had previously seen my GP over a period of more than two years, presenting with feelings of coldness and numbness at the ends of my first and particularly second (middle) finger) of my left hand, and then weakness and loss of function in my thumb, before I was eventually referred to a hospital specialist for assessment. I was completely ignorant about CTS throughout this two year period and also did not notice the progressive and severe muscle wasting that was occurring in my thumb. My consultant made it clear that because of the extended period and progressive effects of nerve damage, release surgery would be unlikely to provide full recovery of function, but it would stop the condition becoming any worse, and relieve numbness and tingling effects in fingers and thumb. As such it was an easy decision to follow the recommendation to undergo surgery.

Now being aware of CTS, and having gathered a better understanding of condition and symptoms, it would seem I did not suffer from the apparently common problems of significant pain and discomfort, or being woken during the night. I did feel a heightened sense of finger numbness and some tingling when first waking up in morning, and to a lesser extent during normal daytime activities. I suspect I may have become de-sensitised to the constant presence of these numbness feelings, to the extent that dominant feelings in my middle finger probably masked any awareness of changes in sensation in my third or fourth fingers (that apparently I might have expected to experience from the coincident ulnar nerve problem at my elbow).

The symptoms in my right hand at present are some mild numbness at the tips of my thumb, first and second (middle) fingers, similar to that previously experienced in the left hand.

Studying the more common factors thought to contribute to causing CTS, I seem to have a positive risk match on only two factors, i.e. age range (55 to 60) and a squarer wrist profile (0.69 depth/width ratio), all the other factors appear negative risk (no diabetes, no family history, tall and not overweight, male, no particular occupational reasons, and the condition is much worse in my non-dominant hand).

The theory of CTS causation (including the positive feedback cycle) set out on this website strikes me as an extremely credible and very eloquent explanation. This leads me to a conclusion that a positive feedback cycle has probably now commenced in my right hand following the recent history with my left hand. If that is likely to be the case, then I am thinking it best to have the surgery now to obtain a lasting solution, rather than seeking a short-term fix (not keen on injections) or waiting for a problem to build up that may then cause permanent nerve damage, not fully recoverable even after later surgery.

What I don’t know is how much my history of severe effects already occurring on my left side pre-disposes me to this repeating itself sooner or later on my right side? Also what is the evidence from the wider patient population regarding the likelihood of CTS occurring in both hands rather than just one hand?

I have tried to provide plenty of information so that any relevant factors to my individual case are known. Any expert advice you can provide me on the above would I hope prove valuable in helping me make the best decision on whether to proceed with surgery now, or hold back and monitor with future NCS tests for evidence of further deterioration.

Using the guidance notes on this website, I have interpreted my NCS results to indicate category 5 CTS in my left hand. I don’t have enough knowledge or confidence to interpret the correct category for my right hand (hopefully I can email the NCS results for your expert assessment).



Here I'm going to try to answer both the questions at the end of your posting here and also some of the ones in the website feedback forum.

Firstly the posting here. Your very detailed account of your history illustrates quite well that the range of individual variation in the way CTS presents in different patients is quite wide and that although there are 'typical' symptoms, there is no single symptom or sign that everyone gets.

A comment about the positive feedback loop theory - one of the key things to appreciate about this is that, IF that theory is correct, then such feedback loops can be broken, and that is what I suspect steroids and splinting achieve in some patients. There also seem to be cases which settle without any intervention so even though it can be self re-inforcing once established it does not seem to be an inevitably progressive problem in all cases once established.

I don't belong to the surgical school which advocates early surgery for all cases I'm afraid and I would only be convinced by this argument if there were never any long-term ill effects from surgery. A decision should be made on treatment for each affected hand taking into consideration the potential risks and benefits of all the effective options.

The degree of symmetry between the right and left hands of the same patient, particularly in respect of how CTS evolves over time and how it responds to treatment, is not an area that has been well explored in the literature. I have speculated in the past about whether a history of failed carpal tunnel surgery on one hand might inrease your risk of having trouble with surgery on the second hand, because I seem to see a few too many patients with bilateral failed surgery and it is theoretically possible that poor prognostic factors for surgery might apply in both hands of the same patient. It is quite clear however that CTS is mostly a bilateral condition so having it in one hand is highly predictive of eventually getting it in the other one even if they don't occur simultaneously to begin with.

Now on to the things from the other posting - I've copied it here and edited it down so that I can see what I'm trying to reply to.

IF2 - a) Your notes make reference to the tunnel being converted into a trench following the surgery, but does it stay like this or eventually heal/re-join? I have read comments elsewhere the TCL reconnects with scar tissue resulting in a slightly larger circumference. I have also read some notes elsewhere indicating this internal healing process may typically occur 6 to 8 weeks after surgery. It would be nice to know what the true situation is from a source of authority and expertise like yourself.

JB - I don't think anyone really knows what the 'true' situation is and it probably varies from patient to patient. Judging by ultrasound imaging, filling in of the gap, by scar tissue is relatively common, as you might expect, but there is probably considerable variation in the mechancial properties of this tissue between patients and scar tissue tends to undergo extensive remodelling over time so it's hard to specify a period of time with an 'end'. Combine that with the variability between patients and I think suggestions that it takes 'x' weeks to heal are probably meaningless for the individual patient 

IF2 - b) The patient can see and understand how well the surface wound is healing, but has no idea what is happening at a deeper level inside the hand. I presume the healing and recovery process will vary across the patient population, even so, any qualified guidance that can be provided on general expectations about the recovery process and timings of the TCL would still be valuable.

JB - see above. A serial ultrasound study, repeating scans every few days for many weeks after surgery would be interesting and if I ever need my left carpal tunnel decompressing I will do it - however so far I have remained free of the condition myself.

IF2 - c) Does the internal healing (or otherwise) of the TCL directly relate to the pillar pain topic you already comment on in the website? (I note that after more than 10 weeks post-surgery, I cannot put any real pressure on the base of my palm without feeling discomfort, and I am avoiding pushing up with the affected hand when getting up out of a chair in fear of affecting the internal healing process? Will I be left with permanent tenderness of palm heels that can’t support my body weight, or does the tenderness usually disappear (fully or largely) after a certain number of months?

JB - You can only really answer this one statistically, and even then the figures are not very precise. Basically the longer you follow people up after surgery the more of them will be free of scar tenderness and pillar pain - the fall in incidence of these problems after surgery seems to continue for at least 1-2 years and no-one has done a high quality serial follow-up study of a large group of operated patients in order to plot this over time. A few patients are left with seemingly more or less permanent, troublesome symptoms so I won't guarantee that yours will resolve but it is is fairly early days yet so you still have a good chance that, eventually, it will settle.

IF2 - d) Taking account of above comments, and my hospital experience where no guidance was given on use of hands during recovery regarding weight bearing on base of palms, I think any guidance you can provide to cover this area could only help interested patients with their recovery.

JB - I've mostly answered this in the other forum I think - we don't really know the best way to manage this post-op.

I hope that helps a bit. Being a neurophysiologist I rely quite heavily, though not exclusively, on nerve conduction results to help me advise patients on their decision making so if you want to send me yours I will happily take a look. JB

PS - I've just seen those NCS results by email They show a grade 5 left CTS along with quite a significant left ulnar nerve lesion at the elbow - I presume these were before surgery. The right hand results are not convincingly abnormal on the strength of those figures alone (and without knowing that lab's normal values) for either the median or the ulnar nerve. I would intepret this as meaning that your right and left hands are very different so I would not extrapolate too much from the events on the left side when trying to decide what to do anout the right one. JB


Hello Jeremy. I would like to update you on what has happened since April 2015 when I first posted this topic on my initial case history and asking for advice on whether to have surgery on my RHS. I hope you will have time to review and comment.

SUMMARY OF PREVIOUS CASE HISTORY: Following GP referral, visited orthopaedic surgeon in Sep 2014, had a NCS in Oct 2014, diagnosed on my left side as having severe CTS and severe ulnar neuropathy at elbow, and on my right side as having mild indications of both conditions. In Jan 2015 I had Carpal Tunnel and Cubital Tunnel release surgery on my LHS. In April 2015 you kindly reviewed my NCS data and classified me as CTS Grade 5 LHS and Grade 0 RHS. You were also not convinced by the NCS data of any ulnar nerve abnormality at my right elbow.

UPDATE SINCE April 2015: The information you provided at that time gave me the confidence to conclude a need for surgery on my RHS wrist and elbow was not yet clear or proven. I felt the best strategy was to hold back on surgery, and instead undertake a new NCS. This would help to quantify any improvement since surgery on my LHS, and any change or deterioration on the RHS. I envisaged further NCS test/s could then be commissioned at appropriate intervals, in order to monitor and quantify the rate/extent of any progressive nerve deterioration on RHS, thereby identifying reliably a need for surgery if and when my case a stage where onset of permanent nerve damage was imminent. I have to say undergoing NCS tests is not a pleasant experience personally, but if it provides the means to reliably measure and quantify nerve function and condition, and avoid unnecessary surgery, then it is definitely worth enduring a short period of discomfort. I would have thought this approach could also save the NHS some money (a NCS is surely less expensive than an unnecessary operation?).

Sadly when I met the surgeon regarding my decision on whether to proceed with surgery, there was a complete refusal to consider or discuss my wishes to undertake a further NCS. The surgeons view was there would be absolutely no benefit or relevance for undertaking any more NCS tests in helping to inform and decide on the need for surgery. A fundament disagreement, and at this point the surgeon discharged me and referred me back to my GP.

In July 2015 my GP agreed to refer me to the NHS hospital Neurophysiology department for a new NCS, and this was eventually carried out in Feb 2016.

I have only just obtained a copy of the new NCS data. As a patient I have tried to compare and interpret changes between the original and new NCS data. I have assumed that increased latency, reduced conduction velocity and reduced amplitude would each be indicators of nerve deterioration (am I correct?). On this basis I have concluded the following:
(1) My LHS median nerve post surgery is now worse, with CTS now at severity GRADE 6 rather than your previous GRADE 5?
(2) There may be some indications of deterioration in sensory and motor function of my RHS median nerve, based on the reduced amplitude readings over the 16 months interval between the two NCS tests?
(3) Having studied your website guidance notes again on how to define the CTS severity scale, I still cannot with any confidence assign an updated CTS grade for my RHS!

To remove my guesswork I would of course be grateful for your expert review and assessment of the data. I will therefore email the new NCS to you, together with another copy of the original NCS just in case you did not still have this to hand.

As it is 17 months after the CTS release surgery on my LHS, I guess my “post operation recovery/improvement period” is by now well and truly over. The numbness sensations at my finger tips (thumb, index, and particularly middle finger) are still there and have never really improved since the operation (contrary to the surgeon’s prediction that the numbness would go). Is there a possibility this numbness might still go at some later stage? On a positive note, the pillar pain and sensitivity to significant and heavy loads placed on the heel of palm is no longer a concern, with things “back to normal” after about 10 to 12 months post operation, and the incision scar on my palm is now barely visible.

There is semi-numbness sensation at the tips of thumb and fingers on my right hand, but not as as much as on my LHS.

I would welcome any comments you may have on what I’ve presented above. The three main issues presently on my mind, and which I would benefit from guidance on, are as follows:

(1) If I am correct in thinking my LHS CTS severity GRADE has worsened in the 16 month interval between the two NCS tests, then did this deterioration most likely occur in the 3.5 months before or 12.5 months after operation? Is this and the continuing numbness after surgery an indication the carpal tunnel may not have been fully released during surgery, or just attributable to severe and irreversible nerve damage prior to surgery? Is there any further diagnosis possible to clarify?

(2) Am I still at CTS GRADE 0 on my RHS, or has there been a change with an initial trend of nerve deterioration now evident from the latest NCS data? What would be an appropriate maximum time interval before undertaking a further NCS to monitor for deterioration on my RHS (bearing in mind that I do not feel confident in relying on my own ability for sensing a worsening condition or experiencing the classic patient symptoms, based on my previous LHS case history set out in my original posting)?

(3) I had asked my GP for the new NCS to be on both wrists and elbows, but it transpired that I was only referred for tests on the wrists. Based on the fact that I did have a significant ulnar nerve problem at LHS elbow without symptoms at fingers, I wanted to be tested again on the RHS elbow. Do you think I should request this now, or am I safe to wait until the next time that I (hopefully) obtain another referral from GP for future NCS on RHS wrist?

Finally I’m sure that many users of this forum and visitors to the website would agree that the interest you show, support you provide, and informed comments you make to CTS sufferers are all incredibly valuable and long may it continue……


First of all I'm sorry to hear about the near argument with the orthopaedic surgeon about further NCS. Unfortunately there is considerable disagreement between my view of the role of NCS in managing CTS and the views of a substantial part of the surgical establishment. I'm trying to develop well documented evidence that will help to improve understanding and hopefully effect some reconciliation but it's a long process and there are probably things that I am wrong about at present as well as right.

The relative costs of things are a complicated issue in themselves and health economics is a field by itself. As a rough indication a carpal tunnel decompression is currently costed by the NHS at approximately 900 and a set of nerve conduction studies at about 170 so you can soon run up a bill equivalent to surgery by doing serial tests. It's worth noting however that both of these figures are 'back of an envelope' estimates with little relation to the real cost of carrying out the tests. Many years ago I tried to cost a set of NCS for CTS, taking into account the staff and buildings costs and the consumables and the depreciation on the machine. We came to a figure of 14 pounds then!

You are exactly right about which way changes in these measurements indicate deterioration. Your left CTS has indeed gone from grade 5 to grade 6. Obviously I cannot tell whether this deterioration occurred before or after the operation but taking the results at face value, and faced with a patient whose symptoms have not satisfactorily resolved after surgery, my first assumption would be that this indicates incomplete division of the transverse carpal ligament - statistically by far the commonest explanation for this sequence of events. I find it a little odd that the neurophysiologist has not commented in the report on the fact that he has previously tested you and that the results have changed but he may have been working from very limited information perhaps? It's pretty much standard for private and NHS record systems to exist in glorious isolation from each other. I've always thought patient held records were a good idea myself. It's a long time after surgery now to be investigating that left hand but I personally would use ultrasound scanning to try and get a better idea what is going on inside the wrist. You may be hard pressed to find someone in your area with the appropriate skills and experience to do this though.

I remain rather sceptical about the right hand CTS but we are still handicapped by not knowing the normal values for that particular laboratory. This hinges around the sensory conduction velocity for the median nerve which was 46.4 m/sec in the first studies and 45 m/sec on the second set of studies. In my lab anything faster than 45 m/sec is normal (and 'mild' or grade 2 CTS is < 40m/sec) but if the lower limit of their local normal range is 48 m/sec then both of those would be considered slow and justify the label CTS. I think it is interesting however that the ulnar nerve sensory conduction velocities were very similar and radial nerve velocities were not much faster at 50, so 45 to 46 is certainly not spectacularly slow (bear in mind that the margin of error in one of these measurements is probably at least 2 m/sec either side of the measured value). One would like to see a more sensitive comparative test done to explore this further. What I think you can say is that there has been very little change in the right hand between the first and second study conduction velocities so there is no immediate danger of your right median nerve dying from CTS. The sensory potential has got smaller(11.9 microV down to 3.4 microV) but they were recorded on different machines by different people and there can be surprisingly wide variations in amplitudes when you change machines and personnel so it's hard to know if that is significant. The motor potential has changed from 9.7 to 7 mV - not such an impressive difference.

I woud not be too worried about the right ulnar nerve at the elbow because the results from the ulnar nerve at the wrist are OK. JB


Thank you so much for your continued interest and the very quick appraisal of my new posting.

Your comments lead me to the following conclusions and, perhaps not surprisingly, raise a few more questions, as follows.

1) Your last comment about my ulnar nerve is very reassuring. I will follow your advice not to worry about my right elbow for the time being.

2) I also take great comfort from your judgement that my right CTS condition has not significantly deteriorated between the two NCS tests, and there is no immediate danger of nerve damage.

3) For the record, based on your own lab test criteria, does the new NCS still leave me at CTS severity grade 0, or is it now grade 1 (your reply has already told me I have not yet reached grade 2)?

4) I remain very concerned however about the RHS CTS severity gradually building up over time without me realising it, because of my proven inability to pick up or experience the classic CTS symptoms or warning signs. Based on your conclusion that little has changed over the 16 month interval between the two NCS tests, as a layman it would seem reasonable to ask for a new NCS at a similar follow-up interval of say 18 months?
Or can the rate of nerve impairment in CTS suddenly increase, with major changes to severity grade occurring in a matter of only months? As you suggest it is not realistic to expect or request serial NCS testing, but I don’t want my right dominant hand to end up with a severely compromised thumb like my LHS.
Based on what you know about my case to date, do you have a view on when I should ask for another NCS (if significantly shorter of longer than my suggestion of 18 months)?

4) I have a crude way of trying to assess the numbness feelings in my hand, comparing how much numb sensation I get when scrapping the tips of my thumb and fingers individually across the edge of my lower incisor teeth. The middle finger LHS is worst, followed by index finger RHS. Unfortunately this leads me nowhere useful.
Is there anything else I can do as a patient to self-diagnose and monitor for any sign of deteriorating nerve function going forward in the period between NCS tests?

5) Your comments that my right hand sensory conduction velocities are similar in both median and ulnar nerves are, I assume, an indicator that my nerve conduction velocities are generally just a little on the slow side (at the lower threshold of a normal distribution) rather than any abnormality for me as an individual? [As I get older, I’m certainly not as fast as I used to be, so my nerve velocities are just matching my life journey on the slippery slope downwards!]
This makes me wonder that in looking at any new NCS tests I would hope to have in the future, noting any increase in the DIFFERENCE between conduction velocities of median and ulnar nerves, as well as absolute values, may be a useful trend indicator?

6) When I next see my GP I will ask for clarification on what the NCS test lab assumes for a normal low threshold conduction velocity. Are there other questions we should ask at the same time, that would help to give you a full interpretation of test data?

7) Finally to my left hand, thank you for confirming my suspicions. I am very disappointed to establish that my CTS is now worse than before surgery. From the comments you have made, I deduce that in my case at severity grade 5 before surgery, it should not be worse after surgery and there was reasonable expectation that some level of measurable improvement in nerve condition should have occurred following complete division of the TCL.
In my opinion, if there is any possibility a routine CTS surgical procedure could result in a failure to completely divide the TCL (which I understood was the whole point of the operation), then a follow-up NCS after surgery should be a MANDATORY requirement, to validate the operation and prove the nerve has not deteriorated further. As far as I’m concerned, the fact that we know I’m now at grade 6 is absolute proof of the tremendous value and need for routinely undertaking NCS tests before and after surgery, in establishing a factual history of what is actually going on.
In the present situation, my first question is: Would a second operation now at this late stage, with the TCL fully divided beyond any doubt, provide any useful recovery of nerve condition and function?
If there is still some reasonable hope that surgical intervention could improve things, then I can make enquiries about the availability of ultrasound scans as you suggested, to diagnose the possible benefit of further surgery. But if the chances are very low or nil, then there seems little point.

Alternatively, depending on your answer here, my second question would be: Is my median nerve now as bad as it can get, unsalvageable, and effectively dead? If it is indeed too late to recover the nerve condition at all, what is the “end game” I can expect in terms of thumb and finger function, feelings and sensations etc. Am I already there I wonder?

The surgeon who operated on me was a middle aged, experienced upper limb specialist, who I guess had already done hundreds or even thousands of CTS releases. I presume this would reduce, but not eliminate, the statistical likelihood of incomplete division of TCL in my case?

I look forward to receiving any further guidance you are able to provide me.


3) In my lab those results would be normal

4) Usually CTS does not change greatly without the patient knowing about it - when it is deteriorating it usually feels as though it is getting worse and vice versa. The only common exceptions to this are tthe occasional patients in which a change from tingling and pain to numbness is interpreted as an improvement when it actually indicates loss of nerve function, and diabetic patients who seem to get a subtly different pattern of symptoms from CTS. CTS does not usually change suddenly unless there is a precipitating factor for a change such as an unusual bout of strenuous activity, a wrist fracture etc but the range of rates of progression is very wide - some cases even improve spontaneously. I don't do routine repeat NCS simply to measure progress - whenever I do another set it is always to answer a specific question posed by a clinical problem - so if you remain clinically the same I would not suggest repeat NCS at any particular interval - I would be guided by symptoms and signs (see below)

4a) You can improvise ways of 'home testing' two point discrimination with a pair of dividers as a semi-quantittative way of keeping an eye on how sensation is changing and you should watch for weakness and wasting of the thumb muscles - a reliable indicator of nerve damage. There are decent youtube videos showing how to test power in abductor pollicis brevis.

5) complicated question - by my standards your median and unar sensory conduction velocities are OK.  We frequently use a comparison of median wth ulnar nerve in the same hand to diagnose CTS by looking for a difference but such techniques can fall down when the ulnar nerve is abnormal as well - like your left hand. The nerves do get slightly slower with normal aging but not enough to actually cause symptoms - there is plenty of 'functional reserve'

6) Your GP will not know the normal reference ranges for the local neurophysiology lab - if they are not on the report then one can only ask the neurophysiologist.

7) I do indeed generally expect grade 5 to improve with surgery, albeit sometimes slowly. We cannot be sure however that it had not deteriorated from 5 to 6 before it was operated. I would like to see every patient who has this operation tested during the 6 weeks before surgery as a baseline for later comparison but I am generally met with opposition on the grounds of a) "We don't need NCS to tell us a perfectly obvious diagnosis" - which is not the point OR b) "we will have to wait 12 months to get NCS done and that will prejudice the outcome of the eventual surgery" - a valid point but not true in most of the UK. All surgeons, however experienced, have occasional instances of incomplete division of the ligament - any surgeon who has not had this happen either has not done enough carpal tunnel operations or simply doesn't know about it because the patient has not gone back to him/her.

Re-operation when it has been grade 6, presumably, for the last year or more has a poor, but not entirely hopeless prognosis. I would make a judgement based on the current pattern of symptoms and the ultrasound imaging. I doubt if your median nerve is totally dead even with virtually unrecordable motor and sensory potentials. Patients with complete loss of median sensation tend to start burning the ends of the fingers without noticing etc.

I hope that helps somewhat. JB


Thank you for your further comments and advice, as always they are very helpful to me. I will try to monitor symptoms in my right hand, but as I’ve said before I’m not confident about this. I will also now arrange to see my GP about the possibility of an ultrasound scan on my left hand, and I will update this post with any further progress made.

As an aside, I recently suffered an accident, falling heavily, with my left hand taking most of the impact, causing a severe sprain, bruising and swelling. I had a subsequent X-ray and was informed of a small fracture and more importantly displaced bones, implying torn ligament/s. As a consequence I have just had an MRI scan of my left wrist yesterday, to enable further assessment of nature and extent of ligament damage, and potential for repair.

I am wondering whether these images might provide an opportunity to also assess my failed CTS surgery regarding any evidence of incomplete division of TCL and nature of subsequent healing? Do you have a view on how useful the MRI images might be, compared to the ultrasound imaging you recommended?

I mentioned my history of CTS problems and surgery to the radiographer before the MRI scan, and will also raise this when I go back to see the specialist about his assessment of the images regarding my ligament injury.


Someone who is good at MRI of the wrist can probably make something of it but I'm much happier with ultrasound myself. JB

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