What is the treatment for osteonecrosis of the lunate wrist?

Treatment of Osteonecrosis of the Lunate (Kienböck's Disease)

Treatment should be stage-dependent, with immobilization and observation for early disease, revascularization or unloading procedures for intermediate stages with preserved lunate architecture, and salvage procedures for advanced collapse with carpal degeneration. 1, 2

Initial Diagnostic Confirmation

• Begin with plain radiographs (anteroposterior, lateral, and oblique views) to exclude fracture, arthritis, or tumor, though radiographs are less sensitive for early disease 3
• MRI without contrast is the gold standard for diagnosis when radiographs are normal or nonspecific, as it can detect early osteonecrosis before radiographic changes appear 3
• CT may be appropriate for surgical planning when the degree of collapse or bone fragment size is uncertain from radiographs 3

Stage-Based Treatment Algorithm

Stage I (Normal Radiographs, MRI-Positive)

• Prolonged immobilization is the treatment of choice for patients under 20 years old 1
• Initial nonoperative management with immobilization is also appropriate for adult patients with limited lunate involvement 1
• If no response or progression occurs, consider minimally invasive relieving procedures 1

Stage II (Lunate Sclerosis, Early Compression Fracture)

• Revascularization procedures are the primary surgical option when conservative treatment fails and the lunate remains reconstructable 1, 2
• Radial shortening osteotomy is indicated for wrists with negative ulnar variance to unload the lunate 2, 4
• Capitate shortening or radial-wedge osteotomy is indicated for wrists with neutral or positive ulnar variance 2
• Vascularized bone grafting from the distal radius may directly revascularize the lunate and potentially arrest collapse progression, though additional data are needed to confirm superiority over traditional procedures 2, 4
• These unloading procedures can be performed alone or combined with vascularized bone grafting 2

Stage IIIA (Severe Lunate Collapse, Carpus Uninvolved)

• Continue with revascularization or unloading procedures as the carpus remains uninvolved 2
• Direct revascularization with vascularized bone grafting or indirect unloading via radial shortening/capitate shortening remain viable options 1, 2

Stage IIIB (Carpal Collapse with Scaphoid Rotation)

• Treatment shifts to addressing carpal collapse rather than lunate salvage 2
• Scaphotrapeziotrapezoid arthrodesis corrects scaphoid hyperflexion and stabilizes the carpus 2
• Scaphocapitate arthrodesis is an alternative mobility-preserving procedure utilizing functional articulations 2

Stage IV (Degenerative Changes at Radiocarpal/Midcarpal Joints)

• Proximal row carpectomy is indicated when functional articulations remain and the capitate cartilage is preserved 2, 4
• Wrist arthrodesis is the definitive salvage procedure when all functional articulations are lost 1, 2

Special Populations

Systemic Sclerosis Patients

• Watchful waiting with analgesic therapy is appropriate for most patients with systemic sclerosis-associated lunate osteonecrosis, as clinical progression is typically slow and complaints are minor 5
• Operative intervention may be necessary in rapidly progressive cases 5
• Distinguish from wrist arthritis as treatment differs significantly 5

Critical Pitfalls to Avoid

• Do not assume radiographic and clinical findings correlate, as the natural history is variable and symptoms may not match imaging severity 4
• Avoid maximally invasive procedures without clear indication, as superiority over simpler procedures has not been proven 1
• Early diagnosis is crucial to allow for revascularization attempts before irreversible collapse occurs 2, 4
• Protected weight-bearing and regular radiographic follow-up are essential after any surgical intervention to monitor for progression 6

Evidence Limitations

The evidence base for many treatment options remains limited, with no standard therapy that predictably results in healing 1. Traditional procedures like radial shortening osteotomy and proximal row carpectomy have demonstrated reliability for pain relief and functional improvement 4. Newer revascularization techniques show promise but require additional data to confirm superiority 4.