Trauma: Hand Injury

Hand Injury

Scaphoid Fracture

  • The Most Common Carpal Bone Fracture
  • Complications:
    • High Rate of Nonunion (5-25%)
    • Avascular Necrosis (5-10%)
  • Presentation: “Snuffbox” Tenderness
  • Immediate X-Ray May Be Negative
    • CT – Best Modality for Nonunion
    • MRI – If Concerned for Osteonecrosis
  • Treatment: Thumb Spica Cast
    • May Consider Operative Repair (ORIF) if Significantly Displaced or Unstable

Scaphoid Fracture 1

Thumb Spica Cast 2

Flexor Tendons

  • Tendons:
    • Flexor Digitorum Superficialis (FDS): To Proximal Interphalangeal (PIP) Joint
    • Flexor Digitorum Profundus (FDP): To Distal Interphalangeal (DIP) Joint
    • Flexor Pollicis Longus (FPL): To the Thumb
    • Flexor Carpi Radialis (FCR): Primary Wrist Flexor
    • Flexor Carpi Ulnaris (FCU): Primary Wrist Flexor
  • Flexor Zones:
    • Zone I: Distal to the FDS Insertion
    • Zone II: FDS Insertion to the Distal Palmar Crease (Proximal A1 Pulley)
    • Zone III: Palm
    • Zone IV: Carpal Tunnel
    • Zone V: Forearm to the Carpal Tunnel
  • Injuries:
    • Jersey Finger: Avulsion of the FDP
      • Finger Sits in Slight Extension
  • Primarily Repair Tendon Lacerations > 50-60% Width

Finger Flexor Tendons 3

Finger Flexor Zones 4

Extensor Tendons

  • Tendons:
    • Central Slip: To Proximal Interphalangeal (PIP) Joint
    • Lateral Bands: To Distal Interphalangeal (DIP) Joint
  • Extensor Zones:
    • Zone I: Distal to DIP Joint (Or IP of the Thumb)
    • Zone II: Middle Phalanx (Or Proximal Phalanx of the Thumb)
    • Zone III: PIP Joint (Or MCP Joint of the Thumb)
    • Zone IV: Proximal Phalanx (Or Metacarpal of the Thumb)
    • Zone V: MCP Joint (Or CMC of the Thumb)
    • Zone VI: Disruption Over the Metacarpal
    • Zone VII: Wrist Joint
    • Zone VIII: Distal Forearm
  • Injuries:
    • Mallet Finger: Avulsion of Terminal Extensor Tendon Over DIP
      • Characterized by DIP Flexion
    • Boutonniere Deformity: Rupture of Central Slip Over PIP
      • Characterized by PIP Flexion & DIP Extension
  • Primarily Repair Tendon Lacerations > 50-60% Width

Finger Extensor Zones 5

Finger Extensor Tendons 6

Mallet Finger 6

Boutonniere Deformity 6

Thumb Injury

  • Base of Thumb Fracture
    • Types:
      • Extra-Articular
      • Partial Intra-articular (Bennett)
      • Complete Intra-articular (Rolando)
    • Often Caused by an Axial Force Applied to the Thumb in Flexion
    • Image with True AP Thumb X-Rays
      • Consider CT if Fracture Appears Complex
    • Primary Treatment: Closed Reduction and Thumb Spica Cast
    • May Consider ORIF or Percutaneous K-Wire in Select Scenarios
  • Collateral Ligament Injury
    • Ulnar and Radial Collateral Ligaments
      • UCL Injury is 10x More Common
    • Radially Directed Force Caused Hyper-Abduction of the MCP Joint
    • Causes Pain with Pinch or Grasp
    • Imaging: Radiograph (Can Do Stressed Views)
      • UCL Injury – Avulsion or Condylar Fracture
      • RCL Injury – Pronation of Proximal Phalanx
      • MRI or Ultrasound are Available as Well
    • Primary Treatment: Immobilization with Thumb Spica Cast
    • May Consider Operative RCL/UCL Repair in Select Scenarios

Digit Replantation Indications

  • All Thumb Injuries
  • Multiple Digits
  • Zone I (DIP & Distal)
    • Zone 2 (MCP & PIP) Have Poor Outcomes
  • Pediatrics

References

  1. Nakamoto JC, Saito M, Medina G, Schor B. Scaphoid stress fracture in high-level gymnast: a case report. Case Rep Orthop. 2011;2011:492407. (License: CC BY-3.0)
  2. Sasi PK, Mahapatra S, Raj Pallapati SC, Thomas BP. Acute Traumatic Musculotendinous Avulsion of the Flexor Pollicis Longus Tendon Treated with Primary Flexor Digitorum Superficialis Transfer: A Novel Technique of Management. Case Rep Orthop. 2016;2016:2106203. (License: CC BY-4.0)
  3. Gray H. Anatomy of the Human Body (1918). Public Domain.
  4. Kotwal PP, Ansari MT. Zone 2 flexor tendon injuries: Venturing into the no man’s land. Indian J Orthop. 2012 Nov;46(6):608-15. (License: CC BY-NC-SA-3.0)
  5. Griffin M, Hindocha S, Jordan D, Saleh M, Khan W. Management of extensor tendon injuries. Open Orthop J. 2012;6:36-42. (License: CC BY-NC-3.0)
  6. Lee SA, Kim BH, Kim SJ, Kim JN, Park SY, Choi K. Current status of ultrasonography of the finger. Ultrasonography. 2016 Apr;35(2):110-23. (License: CC BY-NC-3.0)