Hand anatomy

1. Extensor compartment
muscles of the hand
Tesfahun k

2. Introduction
• Arranged in compartments(6 compartments)

3. Extensor Pollicis Brevis

4. Abductor Pollicis Longus

5. Associated Pathology
• De Quervain's tenosynovitis is a stenosing
tenosynovial inflammation of the 1st dorsal
compartment.
• Diagnosis is made clinically with radial sided wrist
pain made worse with the Finkelstein maneuver.
• Treatment is generally conservative with thumb
spica braces, injections and in refractory cases, 1st
dorsal compartment surgical release.
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6. Epidemiology
• Incidence
• very common
• ~1 per 1000 annually
• Demographics
• woman > men , 30 - 50 years old
• Anatomic location
• most commonly in the dominant wrist
• Risk factors
• overuse
• golfers and racquet sports
• post-traumatic
• postpartum
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7. Etiology
• Pathophysiology
• pathoanatomy
• thickening and swelling of extensor
retinaculum causes increased tendon friction
• NOT considered an inflammatory process
• may be related to accumulation of
mucopolysaccharides
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8. Presentation
• Symptoms
• gradual onset
• radial sided wrist pain
pain exacerbated by gripping and raising objects with wrist in
neutral
Physical exam
Inspection
tenderness over 1st dorsal compartment at level of radial
styloid
motion
usually normal wrist motion
pain with resisted radial deviation
neurovascular exam
normal

9. provocative tests
• Finkelstein maneuver
• On grasping the patient’s thumb and quickly
abducting the hand ulnarward, the pain over the
styloid tip is painful
• more indicative of EPB > APL tendon pathology
• Eichhoff maneuver
• ulnar deviated wrist while patient clenches thumb
in fist, followed by relief of pain once the thumb is
extended even if the wrist remains ulnar deviated
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10. Imaging
• Radiographs
• recommended views-- AP, lateral views of wrist
• indications
• radiographs usually not indicated
• findings
• may be used to rule out
• - basilar arthritis of the thumb
• - carpal arthritis
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11. Differential
• Thumb CMC arthritis
• Intersection syndrome
• FCR tendinitis
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12. Diagnosis
• Clinical
• diagnosis is made with careful history and
physical examination
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13. Treatment
• Nonoperative
• rest, NSAIDS, thumb spica splint, steroid iinjectin
• indications--- first line of treatment
• technique
• NSAIDS, rest and immobilisation usually first step
• steroid injections into first dorsal compartment usually
second step
• outcomes
• overall corticosteriods found to be superior to splinting
• concomitant splinting and/or NSAIDs after steriods
injection does not improve outcomes
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14. Trt...ctnd
• Operative
surgical release of 1st dorsal compartment
indications
severe symptoms
usually consider after 6 months of failed
nonoperative management
technique
radial based incision proximal to the wrist
protect the superficial radial sensory nerve

15. Try.. ctd..
• Techniques
Surgical release of 1st dorsal compartment
approach
transverse incision with release on dorsal side of 1st
compartment to prevent volar subluxation of the tendon
EPB is more dorsal than APL
has variable anatomy with APL usually having at
least 2 tendon slips and its own fibro-osseous
compartment
a distinct EPB sheath is often encountered dorsally

16. Complications
• Sensory branch of radial nerve injury
• Neuroma formation
• Failure to decompress with recurrence
• may be caused by failure to recognize and
decompress EPB or APL lying in separate
subsheath/compartment
• Complex regional pain syndrome
• Prognosis
• Most cases resolve with non-operative management
• High recurrence rate
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17. Extensor Carpi Radialis Longus

18. Extensor Carpi Radialis Brevis