Kienböck's Disease
Summary
Kienböck's disease is avascular necrosis (AVN) of the lunate bone in the wrist. It typically affects young adults, especially men aged 20-40 years, often in manual workers. The exact cause is unknown but is associated with negative ulnar variance (a relatively short ulna), which increases stress on the lunate. The disease progresses through stages from MRI-only changes to sclerosis, fragmentation, collapse, and eventually wrist arthritis. Treatment depends on stage and ranges from conservative management (immobilisation) to joint-levelling procedures, revascularisation, or salvage surgery (proximal row carpectomy, wrist fusion).
Key Facts
- Definition: Avascular necrosis of the lunate
- Demographics: Young men (20-40 years); Manual workers
- Association: Negative ulnar variance
- Staging: Lichtman Classification (I-IV)
- Symptoms: Dorsal central wrist pain, stiffness, weak grip
- Treatment: Depends on stage; Ranges from immobilisation to surgery
Clinical Pearls
"Negative Ulnar Variance": A short ulna relative to the radius increases load on the lunate and is a risk factor for Kienböck's.
"MRI Before X-Ray": Early disease (Stage I) may show normal X-rays but abnormal MRI.
"Lichtman Stages": I = MRI changes only; II = Sclerosis; IIIA = Collapse, carpal height preserved; IIIB = Carpal height loss; IV = Arthritis.
"Joint-Levelling Works Early": Radial shortening or ulnar lengthening osteotomy works best in Stages I-IIIA.
Incidence
- Relatively rare
- Peak: 20-40 years
Demographics
- M:F = 2-3:1
- Often manual workers (vibration exposure)
- Dominant hand affected more commonly
Risk Factors
| Factor | Notes |
|---|---|
| Negative ulnar variance | Increases lunate loading |
| Single blood supply | Anatomical variation |
| Repetitive trauma | Vibrating tools |
| Systemic disease | SLE, sickle cell (rare) |
Mechanism
- Lunate has variable vascular supply
- Increased loading (negative ulnar variance) + compromised blood supply
- Osteonecrosis → Sclerosis → Fragmentation → Collapse
Consequences
- Loss of carpal height
- Altered wrist mechanics
- Secondary osteoarthritis
Symptoms
| Feature | Description |
|---|---|
| Pain | Dorsal central wrist pain; activity-related |
| Stiffness | Reduced ROM especially extension |
| Weakness | Reduced grip strength |
| Swelling | Dorsal wrist |
| Onset | Insidious |
Typical Patient
Inspection
- Dorsal wrist swelling (late)
- May look normal early
Palpation
- Tenderness over dorsal lunate (proximal to capitate)
Movement
- Reduced wrist extension
- Reduced grip strength
Special Tests
- Axial loading reproduces pain
Imaging
| Modality | Findings |
|---|---|
| X-ray | Normal (Stage I) → Sclerosis (II) → Collapse (III) → Arthritis (IV) |
| MRI | Most sensitive; Low signal on T1 (early diagnosis) |
| CT | Assesses fragmentation and collapse |
Lichtman Classification
| Stage | Features |
|---|---|
| I | Normal X-ray; Abnormal MRI |
| II | Lunate sclerosis |
| IIIA | Collapse, carpal height preserved |
| IIIB | Collapse with loss of carpal height, fixed scaphoid rotation |
| IV | Generalised wrist arthritis |
Ulnar Variance Measurement
- Measured on PA X-ray with shoulder at 90°
- Negative = ulna shorter than radius
Treatment by Stage
┌──────────────────────────────────────────────────────────┐
│ KIENBÖCK'S DISEASE MANAGEMENT │
├──────────────────────────────────────────────────────────┤
│ │
│ STAGE I (MRI changes only): │
│ • Immobilisation (cast/splint) 3 months │
│ • Activity modification │
│ • May progress; MRI monitoring │
│ │
│ STAGE II (Sclerosis): │
│ • Joint-levelling procedure: │
│ - Radial shortening osteotomy (if negative ulna var) │
│ - Ulnar lengthening (alternative) │
│ • OR Revascularisation (vascularised bone graft) │
│ │
│ STAGE IIIA (Collapse, no carpal height loss): │
│ • Same as Stage II (good results still achievable) │
│ │
│ STAGE IIIB (Collapse + carpal height loss): │
│ • STT fusion (Scapho-trapezio-trapezoidal) │
│ • Capitate shortening │
│ • OR Salvage (PRC, fusion) │
│ │
│ STAGE IV (Arthritis): │
│ • Proximal Row Carpectomy (PRC) │
│ • Total wrist fusion │
│ • Wrist denervation (pain relief) │
│ │
└──────────────────────────────────────────────────────────┘
Of Disease
- Carpal collapse
- Wrist arthritis
- Chronic pain
- Loss of function
Of Treatment
- Non-union (osteotomy)
- Stiffness
- Ongoing pain despite surgery
- Failure to halt progression
With Early Treatment
- Good outcomes in Stages I-IIIA
- Joint-levelling can halt progression
Advanced Disease
- Salvage procedures offer pain relief but limited function
- Wrist fusion provides stability at cost of motion
Key Guidelines
- ASSH: Hand Surgery Guidelines
Key Evidence
Radial Shortening
- Effective in early-stage disease with negative ulnar variance
What is Kienböck's Disease?
Kienböck's disease is a condition where one of the small bones in your wrist (the lunate) loses its blood supply and starts to break down. This causes pain and stiffness.
Who Gets It?
It usually affects young adults, especially men who do heavy manual work.
What Are the Symptoms?
- Pain in the middle of the wrist (especially on the back of the hand)
- Stiffness
- Weak grip
How is It Diagnosed?
X-rays and MRI scans show the damage to the bone.
How is It Treated?
Treatment depends on how advanced it is:
- Early stages: Splinting, activity modification, or surgery to take pressure off the lunate
- Late stages: Surgery to remove or fuse bones in the wrist
Primary Guidelines
- American Society for Surgery of the Hand. Kienböck's Disease.
Key Studies
- Lichtman DM, et al. Kienböck's disease: update on management. J Hand Surg Am. 2010;35(5):714-723. PMID: 20407585