Kienböck's disease (lunate necrosis)

Anatomy: Why the lunate is so sensitive

The lunate bone is located centrally in the wrist and transmits high forces between the forearm and hand. Its blood supply comes from fine vessels, some of which run at the ends. This anatomical peculiarity makes the lunate susceptible to circulatory problems. Another influencing factor is the length relationship between the ulna and radius (ulnar variance). If the ulnar variance is negative, the radius is longer in relation to the ulna - this can increase the load on the lunate.

• Os lunatum: central carpal bone element
• Holds loads from gripping and supporting movements
• Finely branched, disruptive blood supply
• Load distribution depending on ulnar/spoke length

Symptoms: How you can recognize Kienböck’s disease

The symptoms often develop gradually and are initially misinterpreted as stress-related wrist pain. Depending on the stage, pain and functional limitations increase.

• Dull, stress-dependent pain on the back of the hand (dorsal), often in the middle
• Pressure pain over the lunate (between the radius and metacarpal)
• Decrease in grip strength, rapid fatigue
• Restriction of movement, especially backward bending (dorsiflexion)
• Occasional swelling, feeling of warmth, rarely cracking
• Increase in symptoms when working with vibration (e.g. jackhammer) or during sports

Warning signs that require prompt clarification: persistent pain over several weeks, increasing loss of function, pain after a fall/trauma.

Causes and risk factors

The exact cause is not fully understood. Several factors probably interact to disrupt the microcirculation of the lunate and increase the mechanical load.

• Mechanical overload: repeated micro-movements, vibration work, intense stress
• Anatomical factors: negative ulnar variance (relative “excess length” of the radius), shape variations of the carpus
• Previous trauma: bruises, falls, rarely fractures
• Systemic influences: Smoking (microcirculation), rarely long-term cortisone therapy or coagulation disorders
• Male gender and age 20-40 years – classic cluster, but everyone can be affected

Diagnostics in Hamburg: step by step

We combine history, clinical examination and imaging techniques to understand the stage and loading mechanics. This is how we derive treatment appropriate to the stage.

Differential diagnoses: Preiser's disease (circulatory disorder of the scaphoid bone), scaphoid nonunion, ganglion, ligament lesions (e.g. SL ligament), synovitis or early arthrosis.

Course and stages (Lichtman classification)

Treatment depends on the stage. The earlier it is detected, the sooner progression and subsequent damage can be limited.

• Stage I: X-ray normal, MRI with bone marrow edema; Structure still preserved.
• Stage II: sclerosis and compaction on x-ray, shape preserved.
• Stage IIIA: Incipient collapse of the lunate without significant misalignment of the carpus.
• Stage IIIB: Collapse with malalignment/instability (e.g. scaphoid flexion).
• Stage IIIC: sagittal fracture line in the lunate.
• Stage IV: Secondary osteoarthritis of the wrist.

Conservative therapy: exhaust it first

In early stages and with moderate symptoms, a conservative approach makes sense. Goal: Relieve pain, not further compromise blood circulation and reduce stress on the lunate.

• Immobilization/splint: individually adapted forearm-hand splint for 6-8 weeks (interval immobilization if necessary).
• Load adjustment: avoid vibration, shock load, heavy lifting; ergonomic adjustments at work.
• Medication: time-limited, needs-based pain and inflammatory medication (e.g. NSAIDs) – taking individual tolerability into account.
• Physio/occupational therapy: edema control, pain-free mobilization, strengthening of the forearm and hand muscles, everyday strategies.
• Orthoses in everyday life/at work: to provide relief during stressful phases.
• Smoking cessation: improves microcirculation.

Note: For some “regenerative” procedures (e.g. medical bone building therapies, hyperbaric oxygen therapy) the evidence for Kienböck’s disease is limited. We provide transparent advice on opportunities and limitations and only use such options – if at all – within the context of clear indications.

Surgical procedures: stage-appropriate and targeted

Surgery is considered if conservative measures are not sufficient, there is a risk of progression or there is already structural damage. The selection depends on stage, ulnar variance, tissue quality and your functional goals.

• Pressure-relieving osteotomies: ulnar shortening osteotomy with negative ulnar variance; alternatively, radial shortening or corrective osteotomy. Goal: Shift lines of force away from the lunate.
• Revascularization: vascularized bone grafts (e.g. pediculated bone chips) to promote blood flow - especially in stage II-early III.
• Head pressure reduction: e.g. B. Capitate shortening (rare, selective) to relieve the lunate.
• Lunatum-preserving procedures plus temporary stabilization: combinations of bone augmentation, wire/screw fixation.
• Lunatum removal (selective) with stabilization: e.g. B. Scaphocapitate fusion after lunateectomy when the lunate cannot be preserved.
• Salvage procedures for osteoarthritis/collapse: proximal row carpectomy (PRK) or partial wrist fusions; Total arthrodesis only with advanced osteoarthritis and high pain.
• Selective denervation of the wrist: pain-relieving without changing the joint mechanics - option for pain and desire to maintain mobility.

Arthroscopic techniques can combine diagnosis and therapy, e.g. B. to assess cartilage and ligament status or for bony measures in selected cases.

Decision-making: We discuss opportunities, risks, workload goals (work/sport) and realistic expectations. There is no standardized scheme - therapy is planned individually.

Rehabilitation and return to everyday life, work, sport

The follow-up treatment is crucial for the result. It is determined procedure-specific and closely accompanied by hand therapy.

• After osteotomies/revascularization: immobilization for 4-8 weeks, gradual mobilization from weeks 3-6, strengthening from consolidation.
• After PRK or partial fusion: functional follow-up treatment, early functional exercises, everyday loads from 6-8 weeks, full loads later.
• Ability to work: office work often after 2-6 weeks, physically demanding more after 3-6 months - depending on the procedure and healing process.
• Sport: released individually; starting with low-pain activities (e.g. ergometer), contact sports/stress with impact effect much later.

Realistic goals are pain reduction and suitability for everyday use. Complete freedom from symptoms or unrestricted resilience cannot be achieved in every case.

Prognosis and possible complications

The course is variable. Some early cases stabilize with relief, others progress despite therapy. Early diagnosis and relieving measures improve the chances of slowing the progression.

• Possible complications of the disease: collapse of the lunate, misalignment of the carpus, secondary osteoarthritis (radiocarpal/midcarpal).
• Surgical risks: infection, delayed bone healing/non-healing (especially with osteotomies), implant irritation, persistent pain, restricted movement, nerve irritation.
• Long-term goals: pain reduction, function and strength maintenance, avoidance/delay of osteoarthritis consequences.

When should you introduce yourself?

• Wrist pain > 4-6 weeks or increasing limitations
• Pressure pain over the lunate with loss of strength
• Complaints after a fall/bruise
• High occupational stress/vibration with renewed complaints

In our practice at Dorotheenstrasse 48, 22301 Hamburg, we clarify complaints in a structured manner and discuss the treatment that is right for you - conservative first, surgical only if there is a clear indication.

Special situations

• Younger patients: consider lunate-preserving procedures (revascularization/relief).
• Vibration work/heavy work: early ergonomic adjustment, if necessary temporary implementation; close occupational medical coordination.
• Concomitant illnesses (e.g. coagulation disorders, steroid therapy): Carefully weigh up the risk and benefit, plan in an interdisciplinary manner.

Our approach: transparent, evidence-oriented

We value transparent information, realistic target agreements and comprehensible step-by-step planning. Where data is limited, we discuss this openly. We make decisions together with you – based on complaints, living conditions and functional goals.