- Discussion:
- disease which involves collapse of the lunate due to vascular insufficiency and avascular necrosis;
- first described in 1910 by Kienbock (republished article);
- disease occurs most often in young adults between 15 and 40 years;
- is usually unilateral;
- etiology:
- vascular impairment;
- single or repetitive microfractures that result in vascular comprimise, causing disruption of blood supply to lunate;
- recurrent compression of lunate between capitate & distal radius which disrupts the intraosseous structures;
- extreme wrist positions and/or repetitive compression loading;
- risk factors: negative ulnar variance;
- of interest, there do not seem to be any reports of Kienbock's disease after the Darrach's procedure;
- natural history:
- ref: Long-term outcome of nonsurgically managed Kienböck's disease.
- Clinical Manifestations:
- wrist pain that radiates up the forearm and stiffness, tenderness, and swelling over lunate;
- passive dorsiflexion of middle finger produces characteristic pain;
- limitation of wrist motion, usually dorsiflexion;
- weakness of grip;
- pain and weakness increase as the lunate collapses and degenerative changes develop, making the disability both
severe and chronic;
- Radiographic Findings:
- initial findings:
- sclerosis of lunate;
- may be normal except for negative ulnar variance; (ref: Ulnar variance in Kienbock's disease.);
- in the study by Bonzar, et al (1998), negative varience was found to be associated with Kienbock's disease;
- lunate progressively loses height and eventually fragments;
- further lunate collapse leads to carpal instability and resultant degenerative joint changes, including formation of cysts w/in lunate;
- degenerative changes may ultimately involve the entire wrist;
- references:
- Kienbock disease and negative ulnar variance
- Negative Ulnar Variance and Kienböck Disease
- Radiographic Progression of Kienböck Disease: Radial Shortening Versus No Surgery
- What Is the Radiographic Prevalence of Incidental Kienböck Disease?
- Modified Stahl's classification of Kienbock's disease:
- stage 1:
- normal structure of the lunate, w/ evidence of compression frx usually appearing as a radiodense or radiolucent line;
- stage 2: rarification along the line of previous compression fractures developing within the first 3 months;
- stage 3: changes of stages 1 and 2 together w/ sclerosis of proximal pole occurring at about 3 months;
- stage 4: fragmentation or flattening of the lunate;
- stage 5: changes of arthrosis of radial carpal and inner-carpal joints;
- Lichtman's Radiographic Classification of Kienbock's Disease
- stage 1: normal except for the possibility of either a linear or a compression frx;
- stage 2: definite density changes apparent in the lunate;
- stage 3A: collapse of entire lunate without fixed scaphoid rotation;
- stage 3b: collapse of entire lunate with fixed scaphoid rotation;
- significance of stage IIIb is that the load is significantly shifted over to the lunate, which will further hasten the collapse;
- stage 4: stage III with generalized degenerative changes in the carpus;
- Treatment:
- Early Disease:
- in early cases, the goal of treatment is to decrease compressive loading of the lunate, which permits revascularization before
collapse can occur;
- w/ a negative ulnar variance, radial shortening, ulnar lengthening, or capitate shortening w/ captitate- hamate fusion is considered:
- each of these procedures unloads the lunate fossa and redistributes load to the scaphoid;
- radial shortening:
- indicated in early disease w/ negative ulnar variance;
- unloads lunate fossa & redistributes load to scaphoid fossa;
- distance of only 2 mm is optimal length to cause a reduced load across the lunate;
- larger changes do not reduce compression but may lead to impingement of distal radioulnar joint or distal ulna w/ carpus;
- Radial shortening for Kienbock disease
- ulnar lengthening
- indicated in early disease w/ negative ulnar variance;
- capitate-hamate fusion:
- STT fusion:
- indicated for Keinbock's disease in early stages (up to stage 3);
- this is slightly less effective in reducing the load across the lunate w/ progressive ulnar deviation of the wrist;
- STT fusion and scaphocapitate fusion unloads the lunate and transfers load to the scaphoid fossa;
- it is essential to hold the scaphoid in neutral or slight dorsiflexion relative to its normal resting position in order to
help unload the lunate;
- excessive scaphoid dorsiflexion will significantly limit wrist motion;
- temporary fixation: 2 K wires from the trapezoid into the scaphoid and one from the
- pins are cut beneat the skin;
- cast is worn for one month, and there-after light ROM exercises are permited, but no heavy lifting;
- usually by 4-6 months, radiographic signs of healing are present, and the pins can be removed;
- references:
- Temporary internal fixation of the scaphotrapezio-trapezoidal joint for the treatment of Kienb�ck's disease: a preliminary study..
- Treatment of Kienbock's disease with scaphotrapezio-trapezoidal arthrodesis.
- Temporary scapho-trapezoidal joint fixation for Kienbock's disease in a 12-year-old girl: A case report.
- vascular bundle implantation:
- preoperatively attempt to determine status of the 2nd and/or 3rd metacarpal artery with a doppler;
- choose either artery (and vein) for implantation into the lunate;
- w/ a standard dorsal approach from the wrist to the web space, isolate the artery and the vein, ligating them at the web space;
- a drill hole is made on the dorsal aspect of the lunate at the border between bone and cartilage;
- currette out as much necrotic bone as possible and then fill the cavity w/ ICBG;
- artery is then inserted into the cavity, and needs to be brought out thru a second drill hole and tied down;
- neutral variance: medial closing or lateral opening radial wedge osteotomy is considered;
- Late Disease:
- proximal row carpectomy:
- proximal row carpectomy may not be appropriate for Kienböck disease since lunate collapse damages joint surfaces of the
capitate and radius;
- wrist arthrodesis:
- indicated in persons who use their hands for heavy labor, have severe degenerative changes, or fail to improve following other
surgical procedures;
- controversial treatment methods:
- lunate excision:
- excision of lunate will initially produce good results, but later, the rest of the carpal bones migrate, leading to joint incongruity,
limited wrist motion and grip strength, and degenerative osteoarthritis;
- removal of lunate has been advocated for > 40 years, but it is not currently very popular;
- migration of capitate into defect, w/ subsequent disarrangement of the remaining carpal bones, is common;
- lunate implant:
- casting:
- immobilization relieves symptoms, but the revascularization of lunate does not readily occur in adults, and a decrease in range
of motion in wrist and grip strength gradually occurs
Ulnar variance in Kienbock's disease.
The vascularity of the lunate bone and Kienbock's disease.
Capitate-hamate fusion for Kienbock's disease. Good results in 8 cases followed for 3 years.
Preoperative factors and outcome after lunate decompression for Kienbock's disease.
Biomechanical analysis of radial wedge osteotomy for the treatment of Kienbock's disease.
Histologic and magnetic resonance imaging correlations in Kienbock's disease.
Transient vascular compromise of the lunate after fracture-dislocation or dislocation of the carpus.
A biomechanical comparison of the methods for treating Kienbock's disease.
Kienbock disease and negative ulnar variance.
A Historical Report on Robert Kienböck (1871–1953) and Kienböck’s Disease.