This document discusses carpal tunnel syndrome, including its boundaries, contents, and causes. It describes diagnostic tests like Phalen's maneuver and Tinel's sign. Electrodiagnostic testing criteria are provided. Conservative treatments like splinting and steroid injections are mentioned. The evidence that carpal tunnel release surgery has better outcomes than injections is summarized. Key points are that carpal tunnel syndrome involves compression of the median nerve in the wrist. Physical exam maneuvers and electrodiagnostic testing can aid in diagnosis, though clinical diagnosis is most important. Surgery appears more effective than injections for relieving symptoms long-term.

2. Dr. A.MOHAN KRISHNA
M.S.ORTHO, MCh ORTH(U.K)
Consultant Orthopaedic surgeon ,
Trauma, Arthroscopy, Arthroplasty Surgeon
Apollo hospitals, Hyderabad
Consultant Orthopaedic Surgeon at
www.drmohankrishna.com
www.healthyjointclub.com
www.bonesandjointsclinic.com
www.drmohankrishna.com
www.healthyjointclub.com
www.bonesandjointsclinic.com

3. Carpal tunnel syndrome, the most common focal peripheral neuropathy,
results from compression of the median nerve at the wrist.

4. Boundaries of carpal tunnel:
Volarly : transverse carpal ligament
Dorsally : Carpal bones, deep volar carpal ligaments and volar interoseeous ligaments
Laterally : scaphoid tuberosity & Trapezium
Medially : Pisiform & hook of hamate
Contents: 9 Tendons and median nerve
Tendons: The tendon of Flexor pollicis longus
4 tendons of Flexor digitorum profundus
4 tendons of Flexor digitorum superficialis
Transverse carpal Ligament : Flexor Retinaculum
Thick fibrous band from the tuberosity of scaphoid & a portion of trapezium to the Pisiform & hook of
hamate.

7. Aberrant Anatomy
- Anamalous flexor tendons
- Congenitally small carpal canal
- Ganglion cysts
- Lipoma
- Proximal lumbrical muscle
insertion
- Thrombosed artery
Infections
- Septic arthritis
- Mycobacterial infections
- Lyme disease
Inflammatory
conditions
- Flexor tenosynovitis
- Connective tissue diseases
- Gout or pseudogout
- Rheumatoid arthritis
Meatabolic conditions
- Acromegaly
- Hypothyroidism
- Amyloidosis
- Diabetes
Increased canal volume
- Pregnancy
- Obesity
- Edema
- Congestive heart failure

12. Sensory disturbance
Weakness in thumb abduction
Thenar atrophy

13. In this test the wrist is flexed upto 90 degrees for a period of one minute. Patient is then
asked for the complaints of tingling, numbness an or pain in the first 3 fingers.
This test can be quantified by noting the time taken for the symptoms to appear.
There are several ways of positioning the wrist for eliciting the test.

14. Elicitation: Tap over the median nerve as it passes through the carpal tunnel in the
wrist.
Positive response: a sensation of tingling in the distribution of the median nerve over
the hand.
Elicitation: Tap over the median nerve as it passes through the carpal tunnel in the
wrist.
Positive response: a sensation of tingling in the distribution of the median nerve over
the hand.

15. Gentle pressure directly over carpal tunnel  paresthesias in 30 seconds or less
Better for wrists with limited motion
Highest sensitivity/specificity of all physical exam tests
Gentle pressure directly over carpal tunnel  paresthesias in 30 seconds or less
Better for wrists with limited motion
Highest sensitivity/specificity of all physical exam tests

16. Moberg 1958
•Static (nl < 6mm) and Moving (nl = < 3mm)
•Abnormal = severe nerve compression
Moberg 1958
•Static (nl < 6mm) and Moving (nl = < 3mm)
•Abnormal = severe nerve compression

17. Von Frey hairs (1898)
Five selected thresholds:
- normal (2.83),
- light touch (3.61),
- protective (4.31),
- loss of protective (4.56),
- loss of deep pressure (6.56)
- Abnormal > 2.83 (eyes closed)
Von Frey hairs (1898)
Five selected thresholds:
- normal (2.83),
- light touch (3.61),
- protective (4.31),
- loss of protective (4.56),
- loss of deep pressure (6.56)
- Abnormal > 2.83 (eyes closed)

18. Test Sensitivity Specificity
Phalen’s 75% 62%
Tinel’s 64% 90%
Compression 87% 90%
S-W monofilament 65% 42%
Vibrometry 87% ?

19. EMG/NCV criteria:
-Sensory latencies (DSL)>3.2ms (most sensitive),
-motor latencies(DML)>4.2ms.
EMG conduction delay:
-distal motor latency >4.5ms for 8cm study;
-distal peak sensory latency >4.0ms for 14cm distance;
-distal peak compound nerve latency >2.4ms for 8cm study.
(AMA Guides 6th ed.)
However:
- 8-22% of patients with –ve Electrodiagnostics and +ve clinical signs improve with carpal tunnel
release.
- In some cases Electrodiagnostics + ve for asymptomatic and –ve for symtomatic
EMG/NCV criteria:
-Sensory latencies (DSL)>3.2ms (most sensitive),
-motor latencies(DML)>4.2ms.
EMG conduction delay:
-distal motor latency >4.5ms for 8cm study;
-distal peak sensory latency >4.0ms for 14cm distance;
-distal peak compound nerve latency >2.4ms for 8cm study.
(AMA Guides 6th ed.)
However:
- 8-22% of patients with –ve Electrodiagnostics and +ve clinical signs improve with carpal tunnel
release.
- In some cases Electrodiagnostics + ve for asymptomatic and –ve for symtomatic

20. Consensus Statement (Am J Pub Health 1998)
• (-) ED test, (+) classic sx = ? If CTS
• (+) ED test, (-) symptoms  CTS
Szabo 1999
•night pain, +ve SW, +ve Durkan’s, +ve Hand diagram = 86% probability of CTS
•all test above -ve = 0.68% probability of CTS
ED tests did not add to diagnostic power
CTS is a clinical diagnosis
ED tests can help:
• identify peripheral neuropathy
• locate other sites of compression
• establish severity

30. •May be beneficial in the long term management
•More studies are needed to confirm it’s usefulness

31. JBJS Evidence-Based Orthopaedics*
“Decompressive Surgery Was Better Than Steroid Injection for Symptomatic and
Neurophysiologic Outcomes in Carpal Tunnel Syndrome ”
PRCT, ED-proven CTS, 20wk f/u
All injection patients had improvement of Pain, NCV better with surgery (not grip)
McCallister, Trumble JBJS (Am) 2006

39. Dr.A.MOHAN KRISHNA
M.S.Ortho., MCh Ortho(U.K).,
Consultant Orthopaedic Surgeon,
Apollo Hospitals, Hyderabad.
Appointments: Secretary : 09247258989
09441184590
08332936085
www.drmohankrishna.com
www.healthyjointclub.com
www.bonesandjointsclinic.com
Email: bonesandjointsclinic@gmail.com