POSTER ABSTRACTS - ISAKOS

decreases and the patella remains centralized,
postoperative anterior knee pain following ACLreplacement
using a BPTB autograft can not be
explained by the results of our study.
E-poster #310
Correlation the Anterior Tibial Subluxation with
Valgus Instability in Chronic ACL Deficient
Knees
Shigeo Takahashi, Nagoya, Aichi, JAPAN,
Tomofumi Yamada, Nagoya, Aichi, JAPAN
Kazutoshi Kurokouchi, JAPAN, Presenter
Mitsubishi Nagoya Hospital, Nagoya, Aichi,
JAPAN
The purpose of the present study is to elucidate
the relationship between the anterior tibial
subluxation in full extension and valgus instability
in chronic ACL unilateral deficient knees. Anterior
tibial subluxation in full extension was quantified
using sagittal MR images. Valgus instability was
determined on the abduction stress test in 20
degrees of flexion. ACL reconstruction was
performed arthroscopically with autogenous
hamstring tendons. Clinical results of ACL
reconstruction, including side-to-side difference
with KT-1000 and IKDC final evaluation, were
examined for more than 12 M (mean 19.9 M) after
ACL reconstruction. In 95 knees, 24 knees had the
anterior tibial subluxation of more than 3 mm (L
group) and 71 knees had of less than 3 mm (S
group). Thirteen knees had instability to valgus
and 11 knees had stability to valgus in L group. In
S group, 18 knees had instability to valgus and 53
knees had stability to valgus. There was a
significant difference between the two groups
(p=0.012). Side-to-side difference of 3.0±2.9 mm
in L group was significantly greater than that of
1.66±2.0 mm in S group (p=0.015). IKDC showed
seven knees abnormal (C) and 17 knees normal or
nearly normal (A or B) in L group; four knees
abnormal (C) and 67 knees normal or nearly
normal (A or B) in S group. There was a significant
difference between the two groups (p=0.049).
Chronic ACL deficient knee with an anterior tibial
subluxation, suggesting the disruption of
secondary restraining structures, inclines to
combine valgus instability and may lead clinical
failure as well.
E-poster #311
Osteochondral Lesions of the Posterolateral
Tibia in ACL Disrupted Knees
Hayden Morris, Melbourne, AUSTRALIA,
Presenter
Adam Dalgleish, Auckland, NEW ZEALAND
University of Melbourne, Melbourne, AUSTRALIA
Bone bruising of the lateral femoral condyle and
posterolateral tibial plateau have been well
documented in association with Anterior Cruciate
Ligament (ACL) disruption. Subluxation of the
lateral femoral condyle onto the posterolateral
tibial plateau has been postulated as the cause.
Chondral lesions are common, most often
affecting the lateral and medial femoral condyles.
Arthroscopic examination of forty-three
consecutive patients with ACL rupture was
performed by a single experienced knee
surgeon. Nine patients (21%) had a chondral
lesion of the posterolateral tibia beneath the
posterior horn of the lateral meniscus, not seen
unless the meniscus was elevated with the
arthroscopic probe. On four occasions a chondral
loose body was identified and removed. Seven of
the nine (78%) had an associated lateral meniscal
tear. Magnetic Resonance Imaging (M.R.I.) was
not accurate in predicting the presence of a
posterolateral chondral lesion but did accurately
identify bone bruising in the posterolateral tibial
region.
Chondral lesions of the posterolateral tibial
plateau in association with ACL tears has not
been previously described. As yet the clinical
implications are unknown and subject to further
study. Chondral loose bodies of unknown origin
may arise from the relatively hidden position
beneath the posterior lateral meniscus. When a
lateral meniscal tear is noted, care should betaken
to examine the lateral tibial plateau and lateral
femoral condyle for chondral defects.
E-poster #313
Comparison of EndoButton® Versus
Bioabsorbable Interference Screw plus
EndoPearl® Femoral Fixation in Hamstring
Anterior Cruciate Ligament Reconstruction: A
Randomized Clinical Trial
Ari E Pressman, Ottawa, Ontario, CANADA,
Monika Volesky, Outremont, Quebec, CANADA
Presenter
Andrew R Pickle, Ottawa, Ontario, CANADA
Donald H Johnson, Ottawa, Ontario, CANADA
Carleton Sports Medicine Clinic, Ottawa, Ontario,
CANADA