Fourth Dorsal Compartment of the Wrist Injection

Other Names

• Fourth Dorsal Compartment of the Wrist Injection
• Fourth Extensor Compartment Injection

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Background

The extensor compartments of the wrist

Key Points

• Needle: 25 gauge, 1.5 inch
• Transducer: high frequency, linear
• Recommended approach is long axis, in plane technique

Anatomy of the Fourth Dorsal Compartment

• Contents: extensor digitorum communis, extensor indicis proprius
• Located immediately ulnar to extensor pollicis longus, listers tubercle

Palpation Guidance vs Ultrasound Guidance

• It is recommended that this injection be performed with ultrasound guidance
• There is no literature comparing palpation and ultrasound guidance

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Indications

• Extensor Tendonitis of the 4th Dorsal Compartment
• Extensor Indicis Proprius Syndrome

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Contraindications

• Absolute
  • Anaphylaxis to injectates
  • Overlying cellulitis, skin lesion or systemic infection
• Relative
  • Can be treated with less invasive means
  • Hyperglycemia or poorly controlled diabetes
  • Lack of symptom improvement with previous injection

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Procedure

Needle and probe position for short axis in plane approach

Ultrasound view for short axis in plane approach

Needle and probe position for short axis out of plane approach

Ultrasound view for short axis out of plane approach

Equipment

• Sterile including chloraprep, chlorhexidine, iodine
• Gloves
• Needle: typically 21-25 gauge, 1.5 inch
• Syringe: 5-10 mL
• Gauze
• Ethyl Chloride
• Bandage
• Injectate
  • Local anesthetic
  • Corticosteroid
• Sterile probe cover

Ultrasound Findings

• Use the high frequency linear transducer
• Tendons of the 4th compartment are easily visualized in short axis

Technique: Short Axis, In-Plane

• Patient position
  • Seated or supine
  • Forearm and hand prone on table
• Transducer position
  • Short axis
• Needle Approach/ Orientation
  • In-plane
  • Ulnar to radial or Radial to ulnar
• Target
  • Space between tendon sheath and tendon
• Pearls and Pitfalls
  • Scan area to avoid any nerves or vessels

Technique: Short Axis, Out-of-Plane

• Patient position
  • Seated or supine
  • Forearm and hand prone on table
• Transducer position
  • Short axis
• Needle Approach/ Orientation
  • Out-of-plane
  • Distal to proximal
• Target
  • Space between tendon sheath and tendon
• Pearls and Pitfalls
  • Out of plane technique is very easy due to superficial nature

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Aftercare

• No significant restrictions
• Can augment with ice, NSAIDS
• Consider placement in a Cock Up Wrist Splint

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Complications

• Skin: Subcutaneous fat atrophy, skin atrophy, skin depigmentation
• Painful local reaction
• Infection
• Hyperglycemia
• Tendon, nerve or blood vessel injury

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See Also

• Procedures Main
• Ultrasound Main
• Hand Pain Main

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