Flexor Tendon Injuries (Hand)

Other Names

• Flexor tendon laceration

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Background

• Classified anatomically into zones
• Relatively rare

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Pathophysiology

• Typically volar laceration-type trauma
• Frequently involve neurovascular injuries
• At risk Anatomy:
  • Flexor Digitorum Superficialis
  • Flexor Digitorum Profundus
  • Flexor Carpi Radialis
  • Flexor Carpi Ulnaris
  • Flexor Pollicis Longus

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Risk Factors

• Unknown

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Differential Diagnosis

Differential Diagnosis Finger & Hand

• Fractures
  • Phalanx Fractures (Hand)
  • Metacarpal Fractures
    • Boxer's Fracture
    • Rolando Fracture
    • Bennett Fracture
• Dislocations
  • Metacarpophalangeal Joint Dislocation
  • Proximal Interphalangeal Joint Dislocation
  • Distal Interphalangeal Joint Dislocation
  • Carpometacarpal Joint Dislocation
• Tendinopathies
  • Extensor Tendon Injuries (Hand)
  • Central Slip Extensor Tendon Injury
  • Flexor Tendon Injuries (Hand)
  • Boutonniere Deformity
  • Swan Neck Deformity
  • Jersey Finger
  • Mallet Finger
  • Trigger Finger
  • De Quervains Tenosynovitis
  • Volar Plate Avulsion Injury
  • Sagittal Band Injury
• Ligament Injuries
  • Gamekeepers Thumb (UCL)
  • Radial Collateral Ligament of the Thumb Injury (RCL)
• Neuropathies
  • Wartenbergs Syndrome
  • Carpal Tunnel Syndrome
  • Guyon Canal Syndrome
• Arthropathies
  • Carpometacarpal Arthritis
  • Finger Arthritis
  • Rheumatoid Arthritis
• Nail Bed Injuries
  • Nail Bed Lacerations
  • Nail Bed Avulsions
  • Subungual Hematoma
  • Paronychia
  • Felon
• Pediatric Considerations
  • Proximal Phalanx Avulsion Fracture (Thumb)
  • Middle and Distal Phalanx Avulsion Fracture
• Other
  • Dupuytrens Contracture
  • Intrinsic Plus

Differential Diagnosis Wrist

• Fractures
  • Distal Radius Fracture
    • Barton's Fracture
    • Chauffer's Fracture
    • Colles' Fracture
    • Die-Punch Fracture
    • Radial Styloid Fracture
    • Smith's Fracture
  • Distal Ulna Fracture
  • Carpal Fractures
    • Scaphoid Fracture
    • Lunate Fracture
    • Triquetrum Fracture
    • Pisiform Fracture
    • Trapezium Fracture
    • Trapezoid Fracture
    • Capitate Fracture
    • Hamate Fracture
  • Essex Lopresti Fracture
• Dislocations
  • Wrist Dislocation (Radiocarpal and/or Ulnocarpal)
  • Carpometacarpal Joint Dislocation
  • Distal Radioulnar Joint Dislocation
  • Lunate Dislocation
  • Perilunate Dislocation
• Instability & Degenerative
  • Scapholunate Instability
  • Lunotriquetral Instability
  • Scaphoid Nonunion Advanced Collapse
  • Distal Radial Ulnar Joint Instability
  • Kienbocks Disease
  • Dorsal Wrist Impingement
• Tendinopathies & Ligaments
  • De Quervain's Tenosynovitis
  • Intersection Syndrome
  • TFCC Injury
  • Wrist Tendinopathies
  • Extensor Carpi Ulnaris Instability
• Neuropathies
  • Carpal Tunnel Syndrome
  • Pronator Teres Syndrome
  • Anterior Interosseus Nerve Syndrome
  • Posterior Interosseus Nerve Syndrome
  • Guyon Canal Syndrome
• Pediatric Considerations
  • Distal Radial Epiphysitis (Gymnast's Wrist)
  • Torus Fracture
• Arthropathies
  • Wrist Osteoarthritis
  • Rheumatoid Arthritis
  • Gout
• Cartilage
  • Osteochondral Defect
• Vascular
  • Hypothenar Hammer Syndrome
• Other
  • Ganglion Cyst of Wrist
  • Ulnar Impingement Syndrome
  • Infectious Tenosynovitis

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Clinical Features

• General: Physical Examination Hand
• Universally present with loss of flexion distal to the lesion
• Inspection
  • Cascade Sign can be used to help evaluate for rotational deformity
• Range of motion
  • Passive and active evaluation
• Neurovascular injury

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Evaluation

• Standard Radiographs Hand
• Ultrasound can be helpful to assess suspected lacerations

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Classification

• Flexor tendon injuries are divided into zones
• Zone 1
  • Distribution: Distal to insertion of FDS
  • Pathology: Jersey Finger
• Zone 2
  • Distribution: FDS insertion to A1 pulley
  • Pathology: Can injury both FDS and FDP
• Zone 3
  • Distribution: A1 pulley to distal carpal ligamnt
  • Pathology: Often associated with neurovascular injury
• Zone 4
  • Distribution: Carpal Tunnel
  • Pathology:
• Zone 5
  • Distribution: Carpal tunnel to forearm
  • Pathology: Often associated with neurovascular injury
• Thumb
  • T1
  • T2
  • T3

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Management

Nonoperative

• Flexion important for function, high risk of morbidity
• Nonoperative management essentially limited to partial lacerations < 60% of tendon width

Operative

• Flexor tendon repair
• Flexor tendon reconstruction
• FDS transfer to thumb

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Return to Play

• Needs to be updated

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Complications

• Tendon adhesions
• Rerupture
• Joint contracture
• Swan Neck Deformity
• Trigger Finger

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See Also

• Hand and Wrist Anatomy (Main)
• Finger Pain (Main)
• Hand Pain (Main)
• Wrist Pain (Main)

External

• Sports Med Review Hand Pain: https://www.sportsmedreview.com/by-joint/hand/

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