Kienbock's disease is a disorder of the wrist that results from avascular necrosis and fragmentation of the lunate bone. It is most common in men ages 20-40 and can develop after trauma disrupts the lunate's blood supply. Symptoms include wrist pain and stiffness. Imaging shows changes in lunate appearance over disease stages, from normal to collapsed. Treatment aims to relieve pain and prevent arthritis.

1. By
Prof Ahmed Al_Gebaly
prof of Radiology
Minia University

2. Kienbock's disease
• Kienbock's disease is a disorder of the wrist. It
is named for Dr. Robert Kienböck, a radiologist
in Vienna, Austria who described osteomalacia
of the lunate in 1910
• Specifically, Kienbock's disease is another name
for avascular necrosis with fragmentation and
collapse of the lunate
• The exact cause of Kienbock's is not known .
The necrosis of the lunate bone can frequently
be traced to a trauma to the wrist, like a
compound fracture, which could cause the
lunate's blood supply to be interrupted
• most people suffering from Kienbock's are
affected in their dominant hand

4. • Damage to the lunate can lead to pain, stiffness, and
in late stages, arthritis of the wrist.
• Kienbock’s disease is most common in men between
the ages of 20 and 40 and rarely affects both wrists.
• Patients often have the condition for months or even
years before they seek treatment, and especially in
its earlier stage it can be difficult to diagnose.
• Most patients with Kienbock’s disease initially
present with wrist pain (dorsal wrist pain ). There is
usually tenderness directly over the lunate bone
• In early stages the x-rays may be normal and special
studies are needed to confirm the diagnosis.
Probably the most reliable special study to assess
the blood supply of the lunate is Magnetic Resonance
Imaging

5. • Mechanical anatomic factors that have been
suggested to predispose patients include:
 Smaller lunate
 Flatter radial inclination : Angle between a line
from the ulnar side of the carpal surface of the
radius to the tip of the radial styloid and a line
perpendicular to the axis of the ulna.
 More radial tilt of the lunate.
 Negative ulnar variance: Disputed by more recent
work.
 High uncovering index of the lunate: Length of the
proximal surface of the lunate that does not
articulate with the radius divided by the total
proximal surface of the lunate. Disputed by more
recent work.
 A trapezoidal shape of the lunate
 The presence of a medial lunate facet articulating
with the hamate

6. Stages of Kienbock’s Disease
• Stage I: Early stages of the disease with patient
reporting symptoms similar to a ‘wrist sprain’.
radiographic appearance of the lunate is normal this
was originally a clinical diagnosis. However, with
advanced imaging techniques we now see bone
scintigraphy is positive and MRI may display signs of
bone marrow oedema within the lunate.
• Stage II: As the disease progresses, patients may
report more persistent pain (including night pain) and
signs of synovitis. Radiographically, the lunate
exhibits increased density, however lunate size and
shape and carpal alignment is maintained.
• Stage IIIA: In this stage, the lunate has collapsed
(loss of height), however the scaphoid maintains a
normal position relative to the rest of the carpus.
• Stage IIIB: characterised by lunate collapse and
rotatory carpal subluxation leading to a scaphoid
“ring” sign on radiographic examination.
• Stage IV: The condition has progressed to advanced
secondary osteoarthritis of the radiocarpal joint, and
the patient will report symptoms of wrist stiffness

8. • Terry Thomas sign: Scapho-lunate diastasis
greater than or equal to 3mm is suspicious for
Dorsal Intercalated Segment Instability (DISI)
• Signet ring sign: flexed, proximal pole of
the scaphoid seen end onScaphoid shortening

9. • The joint spaces
of the wrist have
a width of 2 mm
or less. Only the
radiocarpal joint
is slightly wider

10. • The joint spaces of the wrist have a
width of 2 mm or less. Only the
radiocarpal joint is slightly wider

11. • The joint spaces of the wrist have a
width of 2 mm or less. Only the
radiocarpal joint is slightly wider.

12. • In ulnar deviation or extension the
scaphoid elongates to fill the space
between the radial styloid and the base
of the thumb (the trapezium).
• three carpal arcs: smooth curves joining
the surfaces of the carpal bones

13. • Both with radial deviation aswell as flexion
of the wrist the space between the radial
styloid and trapezium is reduced. As
scaphoid fills this space it will foreshorten
and tilt towards the palm. This will give
scaphoid a signet ring appearance

14. • rotary subluxation
of the scaphoid.
• Scapholunate
dissociation
represents a
significant
ligamentous wrist
injury that is
important to
identify on
imaging. There is
disruption of the
scapholunate
ligament with
resultant
instability.

15. • Scapholunate dissociation with
scapholunate diastasis,"ring sign"
(arrow) and foreshortened appearance of
the scaphoid.

16. • Stage I Normal radiograph (possible lunate
fracture).
• Stage II Sclerosis of the lunate without
collapse. (Portions of the lunate begin to
deteriorate. This shows as a white blemish on
x-rays.)
• Stage IIIA Lunate collapse and fragmentation,
in addition to proximal migration of the
capitate.
• Stage IIIB Lunate collapse and fragmentation,
in addition to proximal migration of the
capitate. In addition there is fixed flexion
deformity of the scaphoid.
• Stage IV Changes up to and including
fragmentation, with radiocarpal and midcarpal
arthritic changes.

17. • This is an X-ray with a patient who has Kienböck’s. Note the
lunate has the appearance
of being a bit whiter than the other carpal bones, and also has
a lucent cyst.

18. • Kienböck disease, also known as lunatomalacia

20. • MRI of a
wrist with
Kienbock’s
disease
showing
loss of
blood
supply to
the lunate
in a
patient
with a
short ulna

21. • This 35 y/o female with chronic left wrist pain
was referred for MRI. Selected T1 and T2
weighted coronal images shown above
demonstrate findings of Kienbock's disease.