What are the treatment options for Kienbock's disease, specifically for the collapse of the lunate bone?

Treatment Options for Kienböck's Disease (Lunate Collapse)

For patients with lunate collapse due to Kienböck's disease, treatment should be staged according to disease progression, with early stages managed conservatively and advanced stages requiring surgical intervention to preserve wrist function and prevent further deterioration. 1

Diagnosis and Staging

Proper treatment selection requires accurate diagnosis and staging:

• Initial imaging: Plain radiographs are the first-line imaging modality but may be normal in early stages 2, 1
• Confirmatory imaging: MRI without contrast is the gold standard for diagnosis when lunate necrosis is suspected 2, 1
• Additional imaging: CT without contrast may be appropriate to assess the degree of carpal collapse, bone fragments, and associated osteoarthritis 2, 1

Staging System (Ficat and Arlet, adapted for lunate)

1. Stage I: Normal radiographs (MRI shows early changes)
2. Stage II: Sclerosis and/or early collapse of radial border
3. Stage IIIA: More severe lunate collapse without carpal instability
4. Stage IIIB: Lunate collapse with carpal instability (scaphoid rotation)
5. Stage IV: Degenerative changes at radiocarpal or midcarpal joints 3

Treatment Algorithm by Stage

Stage I (Early Disease)

• Conservative management:
  • Wrist immobilization (splinting/casting) for 3-6 months 4, 3
  • Rest, ice, and elevation to reduce swelling 1
  • Anti-inflammatory medications for pain control 4
  • Vitamin C supplementation may help prevent disproportionate pain 1

Stage II (Sclerosis without Significant Collapse)

• Conservative management as initial approach 4
• Surgical options if symptoms persist:
  • Revascularization procedures:
    • Direct vascularized bone grafting 3
  • Joint-preserving procedures:
    • Radial shortening osteotomy (for negative ulnar variance) 4, 5, 3
    • Ulnar lengthening (for negative ulnar variance) 4, 5
    • Capitate shortening osteotomy (for neutral/positive ulnar variance) 3
    • Radial wedge osteotomy (for neutral/positive ulnar variance) 3

Stage IIIA (Lunate Collapse without Carpal Instability)

• Surgical options:
  • Revascularization with unloading:
    • Vascularized bone grafting combined with osteotomy 3
  • Unloading procedures as described in Stage II 5, 3
  • Replacement arthroplasty with or without limited intercarpal arthrodesis 4

Stage IIIB (Lunate Collapse with Carpal Instability)

• Surgical options:
  • Limited intercarpal arthrodesis:
    • Scaphotrapeziotrapezoid (STT) arthrodesis 3
    • Scaphocapitate arthrodesis 3
  • Replacement arthroplasty with intercarpal arthrodesis 4

Stage IV (Degenerative Changes)

• Salvage procedures:
  • Proximal row carpectomy 4, 3
  • Wrist denervation 4
  • Complete wrist arthrodesis 4, 3

Rationale for Treatment Selection

• Ulnar variance is a key factor in selecting the appropriate procedure:

  • Negative ulnar variance: Radial shortening or ulnar lengthening preferred 4, 5, 3
  • Neutral/positive ulnar variance: Capitate shortening or radial wedge osteotomy preferred 3

• Biomechanical goal: Decompress the lunate to shield it from shear and compression loads 5

• Age considerations:

  • Patients under 20 years: Conservative management with prolonged immobilization is first-line treatment 6
  • Adult patients: More aggressive surgical intervention may be needed based on stage 6

Monitoring and Complications

• Regular assessment for signs of progression, including worsening pain or decreased range of motion 1
• Monitor for development of carpal instability or wrist arthritis 1
• Delayed diagnosis can lead to irreversible collapse and advanced arthritis 1
• Premature return to activities can worsen collapse and necrosis 1

Clinical Pearls

• Early diagnosis is crucial to prevent progression to advanced stages with irreversible collapse 2
• MRI can detect changes before they are visible on radiographs, allowing earlier intervention 1
• The goal of surgical treatment is to decompress the lunate and provide time for biological healing 5
• While osteotomies do not directly heal the necrosis, they protect the lunate from collapse 5