Extensor Tendon ICD-10
Extensor Tendon ICD-9
- 727.63 (nontraumatic rupture of extensor tendons of hand and wrist)
- 883.2 (open wound of finger with tendon involvement)
- 882.2 (open wound of hand except finger, with tendon involvement)
Extensor Tendon Etiology / Epidemiology / Natural History
Extensor Tendon Anatomy
- Zone VIII: most proximal; musculotendinous junction
- Zone VII: tendons enveloped within tenosynovium and extensor retinaculum.
- Vascular supply: diffusion from the mesotendon Zone VII; Zones I-VI supplied by perfusion from paratenon
- Zone VI: long, ring, and small finger tendons connected by juncturae tendinum
Extensor indicis proprius and extensor digiti quinti (run ulnar respective EDC tendons) provide independent extension of index and small fingers.
- Zone V: tendons centrally located over the metacarpal head. Sagittal bands run on each side of the tendon attaching palmarly to the MCP joint volar plate.
- Zone I-IV: EDC linked to intrinsics (lumbricals/dorsal/volar interossei). EDC tendons extend the MCP (via sling formed by sagittal bands). EDC extends IP joints if hyperextension of the MCP joints is prevented by the intrinsics.
- Intrinsic tendons are volar at the MCP joint (intrinsics flex at MCP); They continue distally as the lateral bands inserting with the EDC centra slip into the dorsum of the middle phalanx; Lateral bands terminate dorsally at the midportion of
the middle phalanx, forming the terminal extensor tendon inserting into the distal phalanx. Intrinsics extend the DIP and PIP joints.
Extensor Tendon Clinical Evaluation
- Some IP extention is possible with complete laceration due to intrinsics. Junctura may allow full extention even if extrinsic tendon is completely lacerated.
- Test extention of each finger individually while holding all others flexed at the MCP joints(blocks pull of juncturae).Comparable to contralateral finger of the noninjured hand.
Extensor Tendon Xray / Diagnositc Tests
- A/P and Lateral views of the affected areas indicated to eval for associated fracture or foreign body: generally normal.
Extensor Tendon Classification / Treatment
- Partial laceration: >50% of its width = operative repair.
- Zones V-VIII: repair with 4-0 nonabsorbable suture using modified Kessler or Bunnell technique.
- Zones III and IV: repair with 4-0 nonabsorbable suture using modified Kessler or Bunnell technique. Repair lateral bands 5-0 or 6-0 suture.
- Zones I and II: repair with 4-0 or 5-0 nonabsorbable suture using running or mattress technique or the tenodermodesis technique (skin and tendon sutured as one layer). Pin DIP joint in extension with k-wire.
- CPT 25270 Repair, tendon or muscle, extensor, forearm and/or wrist; primary, single, each muscle or tendon.
Extensor Tendon Associated Injuries / Differential Diagnosis
Extensor Tendon Complications
Extensor Tendon Follow-up Care
- Zones I and II: keep pinned in extension for 4 to 6 weeks,
- Zones III and IV: short-arc active-motion exercises. Aluminum-foam or molded-plastic splint with DIP and PIP joints in full extension for 4 to 6 wks, then gentle active motion is begun: or early controlled active motion (finger splinted in full extension with exercise performed 4-6x a day in a splint which allows 30-40° of flexion continued for 6 weeks: or dynamic extension splinting.
- Zones V through VIII: dorsal dynamic splint applied 3 to 5 days post-op(wrist in 30° of extension;MCP joints in 10 to 15°of flexion; IP at 0° of extension by rubber bands attached to slings).
Extensor Tendon Review References
- Newport ML, JAAOS 1997;5:59