Wheeless' Textbook of Orthopaedics
C.R. Wheeless MD
Wheeless' Textbook of Orthopaedics
- Discussion:
- collapse of the carpal lunate occurs because of avascular necrosis;
- 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;
- risk factors: negative ulnar variance;
- 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;
- references: Ulnar variance in 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;
- Modified Stahl's classification of Kienbock's disease.
- stage 1:
- normal structure of the lunate, with evidence of compression fracture 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;
- Treatment:
- neutral variance:
- medial closing or lateral opening radial wedge osteotomy is considered;
- early disease:
- w/ a negative ulnar variance, radial shortening or ulnar lengthening 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;
- ulnar lengthening
- indicated in early disease w/ negative ulnar variance;
- 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;
- lunate implant:
- 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;
- STT fusion:
- 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;
- capitate-hamate fusion:
- wrist arthrodesis:
- indicated in persons who use their hands for heavy labor, have severe degenerative changes,
or fail to improve following other surgical procedures;
Ulnar variance in Kienbock's disease.
Problem Disorders of the *Wrist--Symposium:* Kienbock's Disease.
Radial shortening for Kienbock disease
The vascularity of the lunate bone and Kienb:ock'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.
Ulnar variance in Kienbock's disease.
A biomechanical comparison of the methods for treating Kienb:ock's disease.
- Discussion:
- collapse of the carpal lunate occurs because of avascular necrosis;
- 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;
- risk factors: negative ulnar variance;
- 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;
- references: Ulnar variance in 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;
- Modified Stahl's classification of Kienbock's disease.
- stage 1:
- normal structure of the lunate, with evidence of compression fracture 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;
- Treatment:
- neutral variance:
- medial closing or lateral opening radial wedge osteotomy is considered;
- early disease:
- w/ a negative ulnar variance, radial shortening or ulnar lengthening 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;
- ulnar lengthening
- indicated in early disease w/ negative ulnar variance;
- 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;
- lunate implant:
- 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;
- STT fusion:
- 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;
- capitate-hamate fusion:
- wrist arthrodesis:
- indicated in persons who use their hands for heavy labor, have severe degenerative changes,
or fail to improve following other surgical procedures;
Ulnar variance in Kienbock's disease.
Problem Disorders of the *Wrist--Symposium:* Kienbock's Disease.
Radial shortening for Kienbock disease
The vascularity of the lunate bone and Kienb:ock'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.
Ulnar variance in Kienbock's disease.
A biomechanical comparison of the methods for treating Kienb:ock's disease.