Keywords
Kienbock's disease - carpal collapse - radial osteotomy
Kienbock's disease, also known as avascular necrosis of the lunate, was described
in 1910 and classified into progressive radiological stages by Stahl and Decoulx.[1] In Decoulx stages I and II, the lunate keeps its original form and volume, although
with changes in radiological density, flattening of the lunate appears in stage III
and there are already signs of radiocarpal osteoarthritis in stage IV. Lichtman later
divided stage III into A, without carpal collapse, and B, already with carpal collapse.[2]
More recently, new classifications and staging of Kienbock's disease based on magnetic
resonance imaging (MRI) and/or arthroscopy were introduced with theoretical therapeutic
implications.[3]
[4]
[5]
Conservative treatment of the symptomatic disease—immobilization—is generally not
advised,[6]
[7] except in very early cases or children and adolescents,[5] and many surgical techniques have been used to treat Kienbock's disease.[2]
[3]
Hulten stated in 1928 that “cubitus minus” was more frequent in Kienbock's disease
patients and would be the main cause of the disease. That led to the use of lengthening
osteotomies of the ulna and shortening osteotomies of the radius in the treatment
of Kienbock's disease, with good clinical results.[1]
Although that statement was challenged,[8]
[9] biomechanical studies seem to prove that those osteotomies, in fact, lessen the
pressure on the lunate bone.[10]
[11] The shortening osteotomy of the radius, with less bone union problems than the lengthening
osteotomy of the ulna,[12] became probably the most popular surgery for Kienbock's disease around the world,[3] sometimes combined with other techniques.[13]
[14]
Lichtman, following his radiological classification of Kienbock's disease, stated
that with carpal collapse (stage IIIB) “equalization procedures, though they may unload
the lunate, are not likely to reestablish normal carpal architecture and mechanics.”
Therefore, for stage IIIB, scaphotrapeziotrapezoid or scaphocapitate fusion is recommended.
If there is significant synovitis, then the lunate should be excised as well.”[2] This became a dogma for most hand surgeons[15] despite the good clinical results published by many authors with radial osteotomies
in advanced Kienbock's disease.[16]
[17]
[18]
[19]
[20]
[21]
[22]
[23]
Materials and Methods
Since 1985, the only surgical technique used primarily in our Kienbock's disease patients
was radial shortening osteotomy (except cases already with radiocarpal osteoarthritis):
52 cases. All patients files were reviewed, but only the 21 cases with carpal collapse
(Lichtman IIIB) are presented here ([Fig. 1]).
Fig. 1 Case 25: preoperative status and X-rays (1997, 22 years). Pain: 2, flexion–extension:
45 degrees; grip: 10%.
After surgery, patients were asked to visit yearly for revision, but many, living
far away, were lost to follow-up. They were all operated and reviewed by the first
authors of this work. The last clinical and radiological revision was between 1 and
23 years (median: 8).
Only 7 were male, and only 8 left wrists were operated. Age was between 15 and 66
years (median: 32). Patients' complaints had started between 1 month and 3 years prior
to presentation.
Pain was classified into the following:
-
Grade 3 Nakamura: constant, 8 cases.
-
Grade 2 Nakamura: even in light work, 12 cases.
-
Grade 1 Nakamura: only in heavy work, 1 case.
-
Grade 0 Nakamura: no pain, none.
Before surgery, median wrist mobility in flexion–extension was 77 degrees, and prehension
strength, measured with a pneumatic manometer, was 26% of that of the other hand.
These measures were not tested in a spastic patient.[24] A total of 15 patients were considered to have an “ulna minus” and 6 to have a neutral
ulnar variance.[2] Thirteen patients had fragmentation of the lunate bone seen in standard X-rays of
the wrist[25]: “Lichtman IIIC stage.”[26] Classification of the Kienbock's disease in stage IIIB (with carpal collapse) was
done comparing to the contralateral wrist.
The shortening osteotomies of the radius (2–3 mm) were performed in the initial years
using a dorsal approach in the distal metaphysis and fixation with a straight plate
(two patients of this series). The last 19 patients were operated using a palmar approach,[27] with the very distal osteotomy fixed with a T-plate ([Fig. 2]). They were immobilized with an antebrachial plaster splint for 4 weeks and then
started active mobilization for another month followed by formal physiotherapy, if
needed. Work was resumed when a sound union was seen in X-rays, or even before in
cases of light work. Three posterior interosseous neurotomies and one carpal tunnel
release were performed with the osteotomies.
Fig. 2 Case 25: postoperative status and X-rays (2018). Pain: 1; flexion–extension: 110
degrees; grip: 80%; light work.
Results
According to our files review, all patients improved after surgery. Pain, generally
2 or 3 before surgery (median: 2.3), was normally 1 or 0 afterward (median: 0.9);
median flexion–extension of the wrist improved from 77 to 99 degrees; and grip strength
of the other hand improved from 26 to 76%.
None of the six patients with neutral ulnar variance had lasting ulnar pain after
surgery. That was only described with bigger radial shortening,[28] but we must admit that in most of these cases, the distal shortening osteotomy was
wedged - wider on the radial side than on the ulnar one.[29]
Rather subjectively, X-rays were considered improved in just one patient, unchanged
in 11, and worsened in 9, with no correlation with clinical status. Four patients
were reoperated: three with plate removals (two dorsal plates and one palmar) with
posterior interosseous neurotomy and one with Phemister[30] grafted delayed union (operated with a palmar plate) that united quickly with a
good clinical result.
Discussion and Conclusions
Discussion and Conclusions
Etiology and natural evolution of Kienbock's disease are largely unknown,[31] and asymptomatic cases are rather frequent.[32]
[33] Carpal collapse in Kienbock's disease does not progress to radiocarpal osteoarthritis
as in posttraumatic cases,[34] probably because there are no abnormal movements between the carpal bones[35]—it is an adaptative carpal collapse, not a carpal instability.[36]
Intercarpal arthrodesis (with or without lunate excision) lessen wrist pain but also
wrist mobility.[37]
[38] Radial osteotomies lessen wrist pain and improve wrist mobility, and are probably
more effective in increasing grip strength.[38]
These are the main reasons to avoid primary aggressive carpal surgery, such as carpal
arthrodesis, proximal carpectomy,[15]
[39] and others,[40] in Kienbock's disease, even in cases with carpal collapse (Lichtman stage IIIB)
or lunate fragmentation.[25]
Finally, any carpal surgery can be added to an eventually failed radial shortening
osteotomy.[41] As a conclusion, radial shortening osteotomy should not be contraindicated in advanced
Kienbock's disease (without radiocarpal osteoarthritis), as stated,[2]
[5]
[15]
[26] because it achieves long-lasting good clinical results, with very few complications.
