Abstract
Treatment of scapho-lunate (SL) injuries is still a challenge for the surgeon, especially
in chronic cases. The aim of the study isto experimentally cut, specific portions
of scapholunate ligament and extrinsic ligaments and check their corresponding arthroscopic
finding in order to understand the pathogenesis and develop a new classification
system which is an evolution of the present arthroscopic classifications.
Materials and Methods Thirteen cadaver wrists were studied under arthroscopy. Different portions of the
scapho-lunate ligament were subsequently sectioned. In group A the sectioning sequence
was: anterior SLIOL, RSC, LRL, SLIOL's proximal and posterior, DIC, DRC ligament and
ST ligaments (8 cases). In group B it was: SLIOL's posterior and proximal, DIC, SLIOL's
anterior, LRL, RSCL, DRC, ST ligaments (5 cases). The anatomo-pathological findings
after each sectioning were correlated to the classification system proposed (Table
1).
Results In group A, stage 3A was obtained when SL ligament's volar and intermediate portion
and/ or SC/LRL ligaments were sectioned. A stage 3C was obtained when section of posterior
SLIOL was sectioned as well. A stage IV when the DIC was also sectioned. In group
B a stage 3B was obtained by cutting intermediate, posterior portion of the SLIOL
ligament and DIC. A stage 3C was obtained when the anterior part of the SLIOL was
also sectioned. In all cases, sectioning of the SLIOL lead to a stage 3C only if associated
with sectioning of at least one of the extrinsic stabilizers (DIC or SC/LRL). Sectioning
of DIC and SC ligament, in addition to SLIOL led to an arthroscopic stage IV. When
ST, DRC and TH ligaments were also sectioned significant radiological signs appeared
(stage V).
Conclusions This study helps us to understand the anatomo-pathological scapho-lunate lesions
in their different stages of partial lesions. Commonly called scapho-lunate lesions
are complex, involving also extrinsic ligaments.
