Palpation of Wrist Flexors and Extensors

Jun 11, 2024

Lecture Notes: Palpation of Wrist Flexors and Extensors

Overview

  • Flexors of the wrist: Located on the anterior forearm (non-hairy side)
  • Extensors of the wrist: Located on the posterior forearm (hairy side)

Tools for Identifying Muscles

  • Brachioradialis (divider muscle) Test: Flexors medial to brachioradialis; extensors lateral to brachioradialis

Extensor Muscles

General Function

  • Originate from the lateral epicondyle of the humerus
  • Extend the wrist and digits

Extensor Carpi Radialis Longus and Brevis

  • Origin: Longus from the supracondylar ridge; Brevis from the lateral epicondyle
  • Insertion: Longus at base of second metacarpal; Brevis at base of third metacarpal
  • Palpation Technique: Support elbow, have client abduct/adduct wrist to feel muscle contraction, and follow muscle down the forearm

Extensor Digitorum

  • Origin: Lateral epicondyle
  • Insertion: Middle and distal phalanges of digits 2-5
  • Palpation Technique: Have client wiggle fingers or extend wrist and digits; tendons pop up on the dorsum of the hand

Extensor Carpi Ulnaris

  • Origin: Lateral epicondyle
  • Insertion: Base of fifth metacarpal
  • Palpation Technique: Have client adduct/abduct wrist; follow muscle from lateral epicondyle to base of fifth metacarpal

Summary of Extensors

  • Extensor Carpi Radialis Longus: Lateral humerus to base of second metacarpal
  • Extensor Carpi Radialis Brevis: Lateral humerus to base of third metacarpal
  • Extensor Digitorum: Lateral humerus to digits 2-5
  • Extensor Carpi Ulnaris: Lateral humerus to base of fifth metacarpal

Flexor Muscles

General Function

  • Originate around the medial epicondyle
  • Flex the wrist and digits

Flexor Carpi Radialis

  • Origin: Medial epicondyle
  • Insertion: Base of second and third metacarpals
  • Palpation Technique: Have client flex wrist, locate tendon near thumb, follow muscle from wrist to medial epicondyle

Palmaris Longus

  • Origin: Medial epicondyle
  • Insertion: Palmar fascia
  • Palpation Technique: Have client flex wrist, locate tendon in center, follow muscle up to medial epicondyle. Thumb-to-fifth digit maneuver also helps

Flexor Carpi Ulnaris

  • Origin: Medial epicondyle
  • Insertion: Pisiform, hook of hamate, base of fifth metacarpal
  • Palpation Technique: Have client flex wrist, locate tendon near ulna, follow muscle from wrist up to medial epicondyle

Summary of Flexors

  • Flexor Carpi Radialis: Medial humerus to base of second/third metacarpals
  • Palmaris Longus: Medial humerus to palmar fascia
  • Flexor Carpi Ulnaris: Medial humerus to base of fifth metacarpal