What is the prompt treatment for a scapholunate ligament injury?

Prompt Treatment for Scapholunate Ligament Injury

The prompt treatment for scapholunate ligament injury should be early surgical repair within 6 weeks of injury, as this produces significantly lower failure rates compared to chronic intervention. 1

Diagnosis

Imaging

• Initial assessment: Radiographs (standard views)

  • Look for scapholunate diastasis (gap ≥4 mm) and abnormal scapholunate angle (>70°) 2
  • Sensitivity: 46%, Specificity: 99% 3

• Advanced imaging (when radiographs are normal or nonspecific):

  1. MR arthrography: Provides better diagnostic accuracy for scapholunate interosseous ligament tears than conventional MRI 4
  2. CT arthrography: Highest sensitivity (nearly 100%), specificity, and accuracy for detecting scapholunate ligament tears 4, 2
  3. 3T MRI without contrast: Sensitivity 70-87%, specificity 90-97% 4

• Dynamic fluoroscopy: Can detect instability with radial/ulnar deviation views

  • Sensitivity: 53%, Specificity: 99% 3

Treatment Algorithm

1. Acute Injuries (< 6 weeks)

• Direct surgical repair is the treatment of choice 5, 1
  • Open reduction and direct ligament reinsertion using bone anchors 5
  • Consider augmentation with capsulodesis technique 6
  • Post-operative immobilization until transarticular wires are removed 3

2. Chronic Injuries (> 6 weeks)

• Treatment depends on reducibility of scapholunate malalignment:

  a) Reducible static malalignment:

  • Ligament reconstruction produces better radiographic outcomes than repair with/without capsulodesis 1
  • Expect 60-80% of contralateral side motion and 65-90% grip strength 6

  b) Irreducible static malalignment with intact cartilage:

  • More complex reconstructive procedures

  c) Irreducible static malalignment with cartilage loss (SLAC wrist):

  • Salvage procedures tailored to the degree of arthritis 6

3. Partial Injuries

• Arthroscopic treatment shows good results in small studies 6

Outcomes and Prognosis

• Acute repair outcomes: 13/18 excellent results, 3/18 good results in one study 5
• Chronic repair outcomes: Higher failure rates compared to acute repair 1
• Risk factors for poor outcomes:
  • Workers' compensation status 1
  • Chronic intervention (>6 weeks from injury) 1
  • Isolated scapholunate interosseous ligament injuries treated in chronic phase 1

Important Considerations

• Untreated scapholunate ligament injuries can lead to carpal instability and degenerative arthritis 7
• Patients with untreated instability report more pain and restriction in daily activities despite similar functional outcomes in short-term follow-up 3
• Scapholunate ligament injuries are frequently associated with distal radius fractures and should be assessed during fracture treatment 3
• The association between isolated scaphoid fracture and scapholunate ligament injury is rare but possible 5

Post-Treatment Rehabilitation

• For patients without ligament injury: 4 weeks immobilization followed by rehabilitation 3
• For patients with repaired ligament: Immobilization until transarticular wires are removed 3