POSTER ABSTRACTS - ISAKOS

The authors believed that the higher level of ACL
lesion in male BRAZILian INDIAns was
determined by cultural issues and the isolation of
this population was critical for the lack of
diagnosis and treatment of these lesions.
E-poster #379
Endoscopic Anterior Cruciate Ligament
Reconstruction using Fluoroscopic Navigation
System
Hisatada Hiraoka, Saitama, JAPAN, Presenter
So Kuribayashi, Tokyo, JAPAN
Yoshinari Miyamoto, Tokyo, JAPAN
Takumi Nakagawa, Tokyo, JAPAN
Takehiro Matsubara, Tokyo, JAPAN
Akira Fukuda, Tokyo, JAPAN
Naoshi Fukui Tokyo JAPAN
Kozo Nakamura Tokyo, JAPAN
Dept. of Orthopaedic Surgery, Saitama Medical
Center, Saitama Medical School; Dept. of
Orthopaedic Surgery, The Univ. of Tokyo, Tokyo,
JAPAN
We employed a newly developed fluoroscopy
based navigation system for endoscopic ACL
reconstruction surgery to realize ideal graft
placement. With the aid of computer technology,
the system navigates surgical instruments in a
real time manner during surgery. Antero-posterior
and lateral fluoroscopic images of the knee at full
joint extension are obtained at the beginning of
the surgery, and the system displays the predicted
positions of the tibial bone tunnel and the graft
rout on these images before placement of a guide
pin for the tunnel. Because the virtual images for
the tunnel and the graft are displayed on the true
antero-posterior and lateral knee images of full
joint extension irrespective of the actual knee
position, the surgeon can easily place the tunnel
at the optimal location without roof impingement.
Since the obtained knee images were loaded onto
the system prior to the reconstruction procedure,
use of fluoroscopy was not necessary during the
surgery. Using this system, thirty-two ACL
reconstructions were performed so far. Of these
patients, eight knees of eight patients whose
follow-up time was more than twelve months were
evaluated about the locations of tibial tunnels
and grafts by X-p and MRI at one year after
surgery. Results: Lateral X-p and MRI obtained at
the maximally extended knee position revealed
that the grafts were located at the predicted
positions and roof impingement was completely
avoided in all the knees. The optimal location of
the tibial tunnel was confirmed by radiographic
measurement: the ratio of the distance between
Blumensaat’s line and the anterior edge of the
tibial tunnel at the level of the tibial plateau
against antero-posterior width was 0.8 ± 1.2 %,
and the angle between the Blumensaat’s line and
the axis of the tibial tunnel was 3.4 ± 2.2 degrees.
T2 weighted MR images have shown that the graft
was placed close to and in parallel with the
intercondyler roof and they were depicted as low
signal bands in all the patients at 1 year after the
surgery. Corresponding to these results, the
outcome of the surgery at one year was
satisfactory: all the patients had resumed full
range of motion, and the average anterior laxity
measured by KT-2000 was 1.2 mm. Conclusions:
The application of fluoroscopic navigation system
in endoscopic ACL reconstruction enables precise
control of the tibial tunnel location and the graft
rout. Better and more consistent results can be
expected with the use of the system.
E-poster #380
ACL Instability Associated with Pigmented
Vilonodular Synovitis- Case Report
Carlos Eduardo Valiente Ferreira, Porto Alegre,
RS BRAZIL, Presenter
Antonio Balestrin Correa, Porto Alegre, Rio
Grande do Sul BRAZIL
Paulo Roithmann, Porto Alegre, RS BRAZIL
Carlos Poisl Jr, Porto Alegre, RS BRAZIL
Marco Molina, Porto Alegre, RS BRAZIL
COT - Clinica de Ortopedia e Traumatologia -,
Porto Alegre, BRAZIL
Pigmented Vilonodular Synovitis is a relatively
infrequent diagnosis(1.8 cases/million
inhabitants/year),not being commonly associated
with cruciate ligament instability.
This is a case report of a 31 year old female
athlete who has sustained an injury to the knee.
ACL rupture was diagnosed.Non -operative
treatment was indicated and the patient
developed instability and persistent effusion .
Arthoscopic ACL reconstruction was performed
and a synovial biopsy confirmed
PVNS.
This paper aims at describing the pathology,
treatment options and the results achieved.
In conclusion, PVNS is an infrequent diagnosis
that should be considered in cases of persistent
effusion while treating knee ligament injuries.