UL Deformity

Question 1

Waiter’s Tip

Answer 1

Cause:
Erb Palsy (Upper trunk of brachial plexus)

Muscle affected:
Shoulder: Rhomboid, levator scapulae, SA, Deltoid, Supra/infraspinatus, teres minor

Arm: BBC

Forearm: supinator, long extensor of wrist, fingers and thumb

Presentation:
arm: Add+IR,
elbow: Ext,
forearm: Pron

Question 2

Ape hand

Answer 2

Median nerve (recurrent branch & Palmar digital branch)

Muscle affected:
* Lateral 2 lumbricals (#1 & #2)
* OP
* AbdPB
* FPB

Presentation:
* Paralysis & flattened of thenar eminence
* Loss of thumb opposition; weak grip; weak thumb abduction and flexion
* Thumb laterally rotated and adducted

Question 3

Total Claw hand

Answer 3

Klumpke’s palsy (Lower trunk of brachial plexus (C8, T1))

Muscle affected:
Intrinsic hand muscles
Weak wrist and finger flexors

Presentation:
- Wrist in supination, extension
* Claw hand affecting digits #2-5
* Fixed IPJ Flexion and MCPJ hyperextension of digits #2 - 5
* Unable to extend IPJ of digits #2 - 5 due to paralysis of intrinsic hand muscles

Question 4

Claw hand

Answer 4

Ulnar nerve

Resting deformity:
R/F & L/F IPJ = flexion
MCPJ = hyperextension

Motion lost:
- R/F & L/F IPJ Ext

The muscle responsible for the deformity:
- Medial 2 lumbricals-Weakness
- Unopposed FDP–>IPJ in Flexion
- Unopposed ED–>MCPJ in HyperExt

Question 5

Hand of
Benediction

Answer 5

Median nerve (Anterior interosseus nerve)

Muscle affected:
Intermediate layers:
* Pronator teres
*FCR
*Palmaris longus
*FDS

Deep layer:
* Lateral half of FDP
* Pronator quadratus
* FPL

Presentation:
- When flexing fingers (make fist)
- I/F, M/F, thumb cannot flex
- R/F, L/F are spared as medial ½ of FDP is supplied by Ulnar nerve

Unable to:
- IPJ flexion in I/F & M/F
- Thumb flexion
Weakened:
- Wrist flexion

Question 6

Wrist drop

Answer 6

Radial nerve

Muscle affected
* ECRL/ECRB
* ECU
* Extensor digitorum
* Abductor Pollicus longus
* Extensor Pollicus Longus+Brevis
* Extensor Indice, digiti minimi

Presentation:
- At rest
- Wrist stay in flexed position→can’t extend

Unable to:
- Wrist extension
- Thumb extension
Weakened:
- Thumb abduction

Question 7

Crutch paralysis

Answer 7

Posterior cord of brachial plexus
Combination of Radial+Axillary nerve palsy

Muscle affected:

Presentation:

• Weak shoulder abduction, flexion and extension
• Weak shoulder external rotation
• Shoulder may appear adducted and internally rotated
• Wrist drop

Question 8

Elbow paralysis

Answer 8

Musculocutaneous nerve

Muscle affected:
Biceps,
brachialis,
coracobrachialis

Presentation:
Weak elbow flexion and forearm supination