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fibers were ruptured a high risk existed for
complete rupture, i.e. more than 50% of
these cases had evolved to a complete ruptu-
re. Buckley [5], on the other hand, did not
find this correlation.
Decreasing sport participation, especially
knee-stressing activities, allows to limit or
perhaps to avoid the evolution to a complete
rupture [3, 23].
Further degeneration of a partial tear is ano-
ther hypothetic evolution. In fact, some
authors have described ACL cysts of which
the imaging is very similar to an interstitial
rupture. The mucoid ACL cyst could be a
degenerative evolution of a partial tear [10].
Finally, little is known on the evolution of
the associated lesions and the risk of
osteoarthritis [24].
HOW SHOULD WE TREAT
A PARTIAL ACL TEAR?
The initial treatment should be conservative.
Generally, [5, 14, 25] splinting of the knee in
15 degrees of flexion is recommended. The
amount of weight bearing remains contro-
versial.
ACL reconstruction is proposed in case of
significant instability.
There are recently a few reports in the litera-
ture on the repair of one single bundle [6, 26].
This surgical option is an interesting treat-
ment. Nevertheless, this procedure can not
resolve the problem of possible elongation of
the remaining ‘intact’ bundle. Recently, Buda
[7] published some data on MRI with analy-
sis of the residual part of the ACL of partial
tear reconstruction.
Thermal shrinkage for ACL lengthening [17]
has been shown to be unsuccessful.
Another surgical option could be an extra-
articular tenodesis. Amis [2] showed that an
extra-articular reconstruction improved the
knee stability but concluded there is no bio-
mechanical basis for using an extraarticular
reconstruction alone. However the extra-
articular tenodesis could allow a better
control of the laxity, particularly in the late-
ral compartment.
Finally, the use of specific growth factors to
induce and augment ACL healing is an
attractive option and is currently under
investigation in the rabbit model [30].
The treatment of the associated lesions
remains problematic. How should we manage
a meniscal tear in association with a partial
ACL tear? In the case of a peripheral meniscus
tear, the success rate of a meniscus repair pro-
cedure could be lower due to the increased
laxity induced by the partial ACL tear. Perhaps,
the management of associated meniscal tear
should lead us to reconstruct the ACL?
CONCLUSION
In the literature, a partial ACL tear is defined
by anatomical, clinical or radiological para-
meters or a combination of these. Confusion
still exists on this nomenclature because the
anatomical diagnosis of
‘a partial ACL tear’
covers a (1) complete ACL tear which is par-
tially functional due to scarring or (2) a rup-
ture of a single bundle of the ACL or (3) an
interstitial tear or elongation. Little, howe-
ver, is known about the natural evolution of
these different anatomical lesions and the
secondary damage to meniscus and cartilage
tissue that might occur due to the laxity.
In order to improve our knowledge on the
natural evolution, the authors propose the
following terminology and classification: ‘A
partial ACL lesion
can be characterised on
the one side by an (1)
incomplete rupture or
HOW SHOULD WE TREAT A PARTIAL TEAR OF THE ANTERIOR CRUCIATE LIGAMENT?
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