• Proceedings of the KSME Conference
• /
• 2008.11a
• /
• pp.658-663
• /
• 2008

The mechanical study on the anterior and posterior cruciate ligament(ACL, PCL) is of importance because the recent increase of outdoor and indoor activities is directly related to causing sport injuries on the knee joints. Constitutive models for many biological tissues have been known as hyperelasticitic models. The elastic behavior of ACL and PCL may be described by the free energy function which accounts for the matrix and the collagen fibers. This paper addresses a comparison of different types of the free energy function to the existing results.

• Journal of Biomedical Engineering Research
• /
• v.29 no.2
• /
• pp.132-138
• /
• 2008

We investigated the biomechanical properties of a newly designed self-expansion type anterior cruciate ligament (ACL) anchor. The ACL anchor consists of the ring section giving the elastic force, the wedge for maintaining in contact with the femur tunnel wall and the link suspending hamstring graft or artificial ligament. The main design parameters that determine the performance of this device were the expansion angle (${\theta}$) and the thickness ($t_R$). The Ti6Al4V anchors were heated after inserting in a jig for 1 hour at $800^{\circ}C$ in a protective argon gas atmosphere and allowed to cool to room temperature in the furnace. In order to investigate the influence of the expansion angle and the thickness of the ring on the biomechanical properties of the anchor, the maximum pull-out load, stiffness and slippage of the ACL anchor were measured using the pull-out tester, and statistical analyses were also executed. The present results showed that the design parameters gave a significant effect on the performance of the self- expansion type of anchor. The pull-out load of the ACL anchors significantly increased as the thickness of the ring section was increased, having a similar trend for both expansion angles. The ACL anchor showed about 2.5 times higher values of the pull-out load than that of the minimum load (500N)required for the "accelerated rehabilitation". The optimum ${\theta}$ and $t_R$ values of this ACL anchor were suggested to have sufficient resistance against the pull-out force, high stiffness and relatively low slippage after ACL reconstruction.

• Korean Journal of Applied Biomechanics
• /
• v.24 no.1
• /
• pp.27-33
• /
• 2014

In volleyball, the most common injuries are anterior cruciate ligament (ACL) tears. For this reason, volleyball players frequently use knee brace as prophylactic and rehabilitation measures. The purpose of the study was to investigate the effects of knee brace on anterior cruciate ligament injuries risk factors during spike take off in female volleyball players. Fifteen female volleyball players were recruited and performed randomly spike take off with and without knee brace. Kinematics and ground reaction data were collected to estimate the anterior cruciate ligament injuries risk factors. The ACL risk factors are knee maximum flexion angle, thigh maximum adduction angle, thigh maximum internal rotation angle, shank maximum abduction angle, shank maximum external rotation angle, knee maximum extension moment and knee maximum abduction moment. Data were analyzed with paired samples t-test with Bonfferoni collection. Female volleyball players with knee brace had no significant results in knee maximum flexion angle, thigh maximum adduction angle, thigh maximum internal rotation angle, shank maximum abduction angle and shank maximum external rotation angle compare to without knee brace. Female volleyball players, however, with knee brace showed more reduced knee maximum extension moment and knee maximal abduction moment than without knee brace. In conclusion, Female volleyball players with knee brace reduced anterior cruciate ligament stress.

• Journal of the Korean Arthroscopy Society
• /
• v.6 no.2
• /
• pp.188-191
• /
• 2002

The complication caused by a bioabsorbable interference screw composed of Poly-L-Lactic-Acid is rare after anterior cruciate ligament (ACL) reconstruction. We reported a case of a pretibial ganglion at the orifice of the tibial tunnel where the graft tendon had been fixed with a bioabsorbable interference screw $(Bioscrew^{\circledR})$ for ACL reconstruction using autogenous hamstring tendon. The patient was underwent ganglion excision and interference screw removal.

• Journal of the Korean Arthroscopy Society
• /
• v.13 no.1
• /
• pp.53-57
• /
• 2009

The pretibial cyst is a very rare complication after anterior cruciate ligament (ACL) reconstruction. It occurs whatever kind of graft choice or kind of graft fixation method at tibial side. It have been known such as graft necrosis at tibial side, extra-articular leakage of joint fluid through tibial tunnel, foreign body reaction due to breakdown of the bioabsorbable screw and incomplete incorporation of graft to bony tunnel as the cause of pretibial cyst. We experienced one case of pretibial cyst which had undergone ACL reconstruction with autogenous hamstring graft fixed with biodegradable interference screw. We report a rare case of pretibial cyst with literature review.

• Journal of the Korean Society of Physical Medicine
• /
• v.3 no.1
• /
• pp.11-20
• /
• 2008

Purpose : This study was to comparison of EMG of an stable exercise group and unstable exercise group on patients who have had anterior cruciate ligament reconstruction(ACL reconstruction). Methods : The subjects of the study were patients who had no less than 4 weeks after ACL reconstruction and could stand on one leg, and they divided into a control group with 9 patients doing closed kinetic chain exercises on the stable floor and an experimental group with 10 patients doing closed kinetic chain exercises on the unstable floor and in order to compare degrees of the muscle activity of the thigh extensor and flexor was tested each before the exercise, in 3 weeks and 6 weeks after doing exercises by using surface electromyography (Surface EMG). The patients made 3 sets of exercises (10 times per set), each of which consisted of exercises using elastic bands and the squat. Results : There was statistic significance about the vastus medialis muscle. Conclusion : It is thought that the closed-chain exercise could be an exercise program through which patients could enhance the muscle activity of the vastus medialis muscle optionally among the quadriceps muscle and the hamstring muscles which should weaken after ACL reconstruction.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.30 no.4 s.247
• /
• pp.457-464
• /
• 2006

The anterior cruciate ligament (ACL) is liable to a major injury that often results in a functional impairment requiring surgical reconstruction. The success of reconstruction depends on such factors as attachment positions, initial tension of ligament and surgical methods of fixation. The purpose of this study is to find isometric positions of the substitute during flexion/extension. The distance between selected attachments on the femur and tibia was computed from a set of measurements using a 6 degree-of-freedom magnetic sensor system. A three-dimensional knee model was constructed from CT images and was used to simulate length change during knee flexion/extension. This model was scaled for each subject. Twenty seven points on the tibia model and forty two points on the femur model were selected to calculate length change. This study determined the maximum and minimum distances to the tibial attachment during flexion/extension. The results showed that minimum length changes were $1.9{\sim}5.8mm$ (average $3.6{\pm}1.4mm$). The most isometric region was both the posterosuperior and anterior-diagonal areas from the over-the-top. The proposed method can be utilized and applied to an optimal reconstruction of ACL deficient knees.

• Journal of Korean Orthopaedic Sports Medicine
• /
• v.1 no.1
• /
• pp.37-42
• /
• 2002

Purpose : To report a short-term clinical results and technical method of thermal shrinkage with radiofrequency device for anterior and posterior cruciate ligament laxity which is not suitable to indications of reconstructive surgery. Materials and Methods : Nine cases of anterior cruciate ligament injuries (ACL), 5 cases of posterior cruciate ligament (PCL) injuries and 3 cases of combined anterior and posterior cruciate ligament injuries, in which the condition is not indicated as reconstructive surgery, are investigated. The follow-up period averaged 6 months. Results : Instability in living activity, limping and pain were improved with excellent results. But, posterior cruciate ligament thermal shrinkage revealed as recurrent knee laxity progressively Conclusions : The result of thermal shrinkage for partial tear of cruciated ligament was excellent. We believe this procedure is applicable to partial tear of the ACL or PCL which reconstructive surgery is not indicated. Long-term follow-up results were needed.

• Journal of Acupuncture Research
• /
• v.34 no.1
• /
• pp.67-79
• /
• 2017

Objectives : The aim of this study was to report the effect of Korean medical therapy on pain and dysfunction after anterior cruciate ligament (ACL) reconstruction. Methods : A 25-year-old man experienced severe pain after right ACL reconstruction surgery. He received Korean medical treatments such as acupuncture, herbal medicine, and physiotherapy from July 10, 2014 to August 2, 2014. Results : After the treatments, his visual analogue scale scores generally decreased and the range of motion of the right knee improved from $0^{\circ}$ to $90^{\circ}$. Furthermore, the Knee Infury and Osteoarthritis Outcome Score increased from 99 to 142. Conclusion : The findings suggest that Korean medical treatments might be effectively used to treat pain and dysfunction after soft-tissue surgeries such as ACL reconstruction. Nevertheless, further research is warranted because of the limited sample size of this study.

• Journal of the Korean Arthroscopy Society
• /
• v.9 no.1
• /
• pp.65-69
• /
• 2005

It is well known that the two main variants of the anterior cruciate ligament (ACL) ruptures in an adolescent include tibial eminence fractures and midsubstance tears. Authors report a case of 17-year-old girl with simultaneous bilateral anterior cruciate ligament ruptures at the ligamento-osseus junction of tibial attachment which was treated with arthroscopic primary repair.