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A. WILLIAMS
58
In this testing length changes for the
anterolateral ligament described by Claes
et al.
[4] and the anterolateral ligament described by
Dodds
et al.
[5]. In addition he studied the
length change of suture from Gerdy’s tubercle
to Kaplan’s fibres, and also for attachmnent
points for Lemaire and MacIntosh lateral
tenodeses. For the tenodeses the sutures were
placed superficial and also tested deep to the
LCL. The findings showed that the most
isometric lateral anatomical soft tissue was the
iliotibial band with its connection to the femur.
The anterolateral ligament attachment
according to Dodds
et al.
[5] with the femoral
attachment proximal and posterior to the
femoral attachment to the LCL tightened
towards extension and slackened in flexion. An
ALL attachment point to the femur distal to the
LCL attachment to the femur was loose in
extension and tight in flexion, which was not
surprising! All of the lateral tenodesis
procedures performed better than the best ALL
reconstruction so as long as the suture was
taken deep to the lateral collateral ligament.
Subsequent unpublished data shows that testing
reconstructive techniques shows superiority of
ITB-based tenodeses taken deep to the LCL, as
compared to a Lemaire procedure taken super
ficial to the LCL, and an ALL reconstruction in
the position described by Dodds
et al.
[5].
Unfortunately surgical techniques employing a
femoral attachment distal to the LCL attachment
to the femur for ALL reconstruction have been
poularised. Not only are these illogical but,
since they loosen extension, they cannot be
effective; and since they tighten with flexion
they could be harmful to patients.
In summary, the biomechanical testing we have
undertaken at
Imperial College
has
conclusively shown that the anterolateral
ligament is of little significant, although it does
exist, but that the main restraint to internal
rotation in the lateral soft tissue envelope is the
ITB with its attachment to the femur.
REPORTS TO THE
CONTRARY IN THE
LITERATURE
There are a number of papers that have been
written showing apparent importance of the
anterolateral ligament. Unfortunately the
experimental designs for these often include
removal or defunctioning of the iliotibial band.
This means that if the main restraint has been
removed it is not surprising that something that
would normally be less effective becomes
apparently more effective.
The amount of interest in the anterolateral
ligament has been truly astonishing and, at
times, worrying. The concept has been seized
upon and has been rushed to surgery without
the due diligence of proper scientific evaluation.
For some reason the concept has been assumed
to be the truth, and nothing but the truth, and
therefore many of the publications that have
followed are examples of “conformational
bias”. When a concept is embedded in the
human brain everything else seems to fit this
theory. This can be explained by saying “the
eye sees what the brain knows”.
The proper way to deal with a “new discovery”,
even if it is old (!), is to work through the
subject step by step, evaluating the anatomy
followed by the biomechanics, testing proposed
reconstructions in a laboratory and finally
having a committed approach to long term
clinical outcome follow up.