Carpal tunnel syndrome

Carpal Tunnel Syndrome or CTS is a common presentation in Primary Care. This review of CTS on A4Medicine presents the clinician with pathophysiology with relevant anatomy displayed for easy reference. CTS is the commonest compression neuropathy of the upper limb. Presentation of carpal tunnel syndrome and examination is discussed – specific tests as the Phalen’s, Tinel’s and Durkan test are described. The differential diagnosis of CTS is mentioned and the clinician should exclude other causes as cervical radiculopathy and vibration white finger or hand arm vibration syndrome. The management of CTS is discussed and the role of interventions as lifestyle modification, physiotherapy, corticosteroid injections have been mentioned. Referral to trauma and orthopaedics should be considered if surgery is being contemplated. Visual diagrams of CTS, Phalen’s test and Durkan’s test have been shown to aid understanding.

Symptomatic compression neuropathy of the median
 nerve at the level of the wrist. Anatomical compartment bounded on three sides by carpal bones and on palmar side by transverse carpal ligament Contains 
○ 9 tendons with synovial sheaths and 
○ the Medial nerve- divides into recurrent branch and palmar digital nerves ( once passes through the carpal tunnel )
Median nerve contains fibers from all five roots C5-T1
 Anything that causes a 
○ reduction in the volume of this compartment or
○ ↑↑ the pressure within the compartment




 Ischaemia of the median nerve and impaired nerve conduction





 Symptoms of carpal tunnel syndrome

Epidemiology-Commonest compression neuropathy of the upper limb Reported prevalence is between 1% and 7% in European population studies Much more rare in developing countries Three times ↑ common in women High BMI Occupation – repetitive movements Familial and psychosocial factors

Presentation-Intermittent tingling , numbness or altered sensation and burning –> distribution of medial nerve Symptoms often worse at night- can wake patient up Pain in hand , wrist or forearm radiating as far proximally as the shoulder Can be uni or bilateral Reduced grip strength Clumsiness or ↓↓ manual dexterity Trophic ulcers – tips of thumb , index finger or middle finger Severe disease
○ unremitting sensory symptoms
○ weakness
○ thenar mucle wasting Exacerbating factors eg
○ sleep
○ sustained hand or arm positions
○ repetitive hand or wrist movements Ask about relieving factors as changing hand posture or shaking / flicking the wrist Effect on function and activities

Examination-Examine both hands Check for sensory loss – Median N distribution Atrophy of muscles -> thenar eminence Thumb- reduced strength thumb abduction Evidence of trophic ulcer -> dry skin thumb , index & middle fingers
 Tests
○ Phalen’s – flex wrist + 60 sec’s can produce symptoms
○ Tinel’s – tapping lightly over the median N
○ Durkan’s or carpal tunnel compression test 
Direct compression of median nerve at the carpal tunnel
○ Hand diagram – patient marks site of pain or altered sensation on hand diagram
 Examine cervical spine Neurological & musculoskeletal examination of upper limbs

Other possible causes- Cervical radiculopathy Diabetes Hypothyroidism Osteoarthritis Inflammatory arthropathy Stroke Lateral epicondylitis De Quervains tenosynovitis Amyotrophic lateral sclerosis
MND Vibration white finger or hand-arm-vibration syndrome Peripheral neuropathy – any cause Raynaud’s phenomenon Motor neurone disease 
( no sensory component ) Ulnar N compression Rotator cuff tendinopathies

Management-Optimize any underlying condition
 Lifestyle modifications may help- eg
○ avoidance of repetitive movements
○ break from tasks that precipitate symptoms
○ workplace adaptation ( if work related )
○ check if eligible for Industrial Disablement Benefit
 Physiotherapy
 Wrist splinting in neutral position -> particularly for night 
time symptoms 
( can be used first line )
 Steroid injections -> if expertise available + splinting
considered safe and effective Do not suggest NSAIDs ,diuretics , magnets , vitamins or acupuncture
 Surgery
○ carpal tunnel decompression well established treatment
○ day case
○ good evidence of good outcome and patient satisfaction
○ possible complications ( usually rare )
 ♦ scar tenderness ( may persist up to 2 yrs )
 ♦ persistent symptoms
 ♦ N/V injury
 ♦ wound complications
 ♦ bleeding
 ♦ pillar pain → deep aching pain at base of thenar eminence and across the wrist
 ( may persist upto 2 yrs )
Decompression can also be achieved endoscopically

CTS may 
improve spontaneously in
 up to 1/3rd of patients over a 
period of 10-15 
months

Investigations-Electrophysiological studies- EMG
Debate about its use
BMJ review suggests
○ not required to make an initial diagnosis or to initiate Rx in primary care
○ assessment in specialist environment- patient selection for surgery and for evaluation of complex cases , relapse of symptoms or recurrence
 Ultrasound MRI


Referral-Diagnosis not clear Severe symptoms or functional ability is reduced Symptoms recur following surgery Patient request Conservative management has not worked Serious underlying cause suspected as
○ neurological dis
○ inflammatory joint disease
○ peripheral limb ischaemia
○ cervical n root entrapment

LINKS AND RESOURCES

A brief 1 page PIL from American College of Rheumatology https://www.rheumatology.org/Portals/0/Files/Carpal-Tunnel-Syndrome-Fact-Sheet.pdf

For patients who wish to learn more American College of Rheumatology  has a useful online section (has useful information for a whole range of MSK conditions ) https://www.rheumatology.org/I-Am-A/Patient-Caregiver/Diseases-Conditions/Carpal-Tunnel-Syndrome

Exercises and information from Arthritis Research Foundation is here https://www.csp.org.uk/system/files/2_carpal_tunnel.pdf

OthoInfo AAOS has a comprehensive section for patients on CTS https://orthoinfo.aaos.org/en/diseases–conditions/carpal-tunnel-syndrome/

Physiotherapy and exercise for CTS from NHS York Teaching Hospital with video instructions https://www.yourphysio.org.uk/condition-directory/carpal-tunnel-syndrome/

Carpal Tunnel Release Surgery– a useful section on this from BUPA https://www.bupa.co.uk/health-information/muscles-bones-joints/carpal-tunnel-release-surgery

Royal College of Surgeons has a section with downloadable information on CTS https://www.rcseng.ac.uk/search/#SearchTerm=carpal%20tunnel

RCS – full guideline can be downloaded from this https://www.rcseng.ac.uk/-/media/files/rcs/standards-and-research/commissioning/boa–carpal-tunnel-syndrome-guide-2017.pdf

American Academy of Orthopaedic Surgeons – Management of Carpal Tunnel Syndrome Evidence Based Clinical Practice Guideline 2016 can be found here https://www.aaos.org/uploadedFiles/PreProduction/Quality/Guidelines_and_Reviews/guidelines/CTS%20CPG_2.29.16.pdf

Questionnaires on CTS

Boston CTS Questionnaire https://journals.plos.org/plosone/article/file?id=info:doi/10.1371/journal.pone.0129918.s002&type=supplementary

DASH Questionnaire https://www.orthopaedicscore.com/scorepages/disabilities_of_arm_shoulder_hand_score_dash.html

References


1. Carpal tunnel syndrome Clinical Review BMJ 2007:335:343
2. Carpal tunnel syndrome BMJ 2014;349:g6437
3. CKS NHS Carpal tunnel syndrome https://cks.nice.org.uk/carpal-tunnel-syndrome
4. Diagnosing and managing carpal tunnel syndrome in primary care Br J Gen Pract 2014 ;64 (622 ):262-263 https://bjgp.org/content/64/622/262
5. Campbell’s Operative Orthopaedics , Thirteenth Edition Azar.Frederick M., MD Elsevier , Inc
6. Carpal Tunnel Syndrome : Diagnosis and Management Am Fam Physician .2016 Dec 15;94 (12):993-999
7. Carpal Tunnel Syndrome and Median Nerve Lesions Patient UK
8. Treatment of Carpal Tunnel Syndrome Commissioning guide Royal College of Surgeons January 2016
9. BMJ Best Practice – Carpal tunnel syndrome
10. Risk factors in carpal tunnel syndrome The Journal of Hand Surgery : British & European Volume , 29 , Issue 4 , August 2004 , Pages 315-320 ( Abstract )
11. The clinical and cost-effectiveness of corticosteroid injection versus night splints for carpal tunnel syndrome 
( INSTINCTS trial ) : an open-label parallel group , randomised controlled trial The Lancet , Volume 392 , Issue 10156 , 20-26 October 2018 , Pages 1423-1433 ( Abstract )
12. Dale, Ann Marie et al. “Prevalence and incidence of carpal tunnel syndrome in US working populations: pooled analysis of six prospective studies.” Scandinavian journal of work, environment & health vol. 39,5 (2013): 495-505. doi:10.5271/sjweh.3351
13. Sevy JO, Varacallo M. Carpal Tunnel Syndrome. [Updated 2020 Mar 30]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK448179/
14. Carpal Tunnel Syndrome: A Review of the Recent Literature I Ibrahim et al https://openorthopaedicsjournal.com/VOLUME/6/PAGE/69/FULLTEXT/#
15. Atroshi I, Gummesson C, Johnsson R, Ornstein E, Ranstam J, Rosén I. Prevalence of Carpal Tunnel Syndrome in a General Population. JAMA. 1999;282(2):153–158. doi:10.1001/jama.282.2.153 ( Abstract )