Common Extensor Tendon Percutaneous Tenotomy

Other Names

• Common Extensor Tendon Percutaneous Tenotomy
• CET Tenotomy
• Tenex

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Background

Illustration of the 4 muscles of the common extensor tendon

Key Points

• Percutaneous needle tenotomy involves repeatedly fenestrating the diseased tendon under ultrasound with the goal of promoting a healing response
• An 18-20 gauge 1.5 inch needle is ideal for the procedure
• Be sure to council the patient on increased pain following the procedure

Anatomy

• Common Extensor Tendon
  • Composed of extensor carpi radialis brevis, extensor digitorum communis, extensor digiti minimi, extensor carpi ulnaris
  • Common origination at the lateral epicondyle of the distal humerus
  • ECRB tendon is most anterior
  • Function is wrist extension, radial/ulnar abduction

Palpation vs Ultrasound Guidance

• To date, there are no studies comparing ultrasound-guided and palpation-guided approaches

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Indications

• Lateral Epicondylitis

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Contraindications

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

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Procedure

Needle tenotomy of the common extensor tendon showing (a) probe and needle position and (b) length and trajector of needle in-plane.

Percutaneous tenotomy with the "Tenex TX-1". The needle is positioned within the common extensor tendon just distal to the osseous footplate (asterisk). The device has a blunt, 18-g tip (a, small arrows) and larger irrigation sheath more proximally (a, large arrows). When activated, the device creates a snow storm-like artifact due to the ultrasonic vibration of the tip (b)

Equipment

• Sterile prep (including chloraprep, chlorhexadine, iodine, etc)
• Ultrasound with sterile probe cover
• Gloves
• Needle
  • Local anesthesia: typically 21-25 gauge, 1.5 inch
  • Tenotomy: 18-20 gauge, 1.5 to 3 inch needle
• Syringe: 5-10 mL
• Gauze
• Ethyl Chloride
• Bandage
• Injectate
  • Local anesthetic
  • Corticosteroid/ injectate

Ultrasound Findings

• Best visualized with high frequency linear probe
• Common ultrasound findings include:
  • Enthesophyte at the apex of the epicondyle
  • Thickened, heterogenous common extensor tendon
  • Interstitial tearing (often not seen sonographically)
  • Increased flow on color doppler

Technique

• Patient Position
  • The patient is supine or seated
  • Elbow in resting position, flexed to approximately 90°
• Probe Position and Needle Orientation
  • Long axis to the CET
  • Needle is in plane, distal to proximal
• Target
  • Target is the origin of the CET
  • Emphasis on areas that appear tendinotic on US
• Pearls and Pitfalls
  • Small amounts of fluid can be injected into the tendon to ensure adequate distribution
  • Needle is repeatedly passed form superficial to deep, distal to proximal
  • The periosteum should be diffusely abraded
  • There is no max/minimum number of fenestrations; the goal is to fenestrate all abnormal tendon
  • The needle should glide through the tendon easily at the end
  • The decision to inject corticosteroids is controversial and generally not recommended

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Aftercare

• Council patient on increased pain immediately following the procedure

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Complications

• Skin: Subcutaneus fat atrophy, skin atrophy, skin depigmentation
• Painful local reaction
• Infection
• Hyperglycmia
• Nerve or blood vessel injury
• Tendon rupture
  • Frequency unknown

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See Also

• Procedures Main
• Ultrasound Main
• Elbow Pain Main

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