• Journal of the Korean Arthroscopy Society
• /
• v.13 no.2
• /
• pp.97-104
• /
• 2009

Optimal treatment of the torn anterior cruciate ligament (ACL) remains controversial. The complexity of surgically reproducing the natural biomechanical and anatomical function of the ACL has led to a diversity of reconstructive procedures. Controversy continues to exist regarding the best reconstructive procedure for the ACL deficient knee, but currently, there is no ideal method. Because of the increased frequency of ACL injury and the functional impairment resulting from that, the role of mechanoreceptors in the ACL recently has attracted considerable attention. Proper reconstruction of the ruptured ACL does not always have good results. Success after operation may depend not only on the mechanical stability but also on the quality of recovery of proprioception. It is well known that most ACL are ruptured in proximal half and most mechanoreceptors have been reported to be located in the subsynovial layer and near the tibial insertion of the ACL. Expected roles of tibial remnant is to enhance the revascularization and cellular proliferation of the graft, to preserve proprioceptive function, and to be able to acquire anatomical placement of the graft without roof impingement. The remnant of the ruptured ACL has been removed to clearly visualize the ACL footprint or decrease the risk of impingement and Cyclops lesion in most current techniques for ACL reconstruction. Therefore it seems reasonable to assume that preserving the tibial remnant as much as possible as a source of reinnervation, if technically possible without causing impingement, would be of potential benefit to the patient. In addition, it will facilitate the vascular ingrowth and ligamentization of the grafted ACL.

• Korean Journal of Applied Biomechanics
• /
• v.24 no.2
• /
• pp.121-129
• /
• 2014

The purpose of this study was to investigate the effect of the toe headings on the biomechanics of knee joint in drop landing in an attempt to find the potential risk of non-contact anterior cruciate ligament (ACL) injury. Seventeen male college students ($20.5{\pm}1.1$ yrs; $175.2{\pm}6.4$ cm; $68.8{\pm}5.8$ kg), having no neuromuscular injury within an year, participated in this study. Three different toe headings such as toe-in (TI), neutral (N), and toe-out (TO) positions were tested. Motion capturing system consisting of eight high speed cameras and two force platforms were used to collect three-dimensional motion data and ground reaction force data during landing. Results indicated joint angles and peak joint moments were significantly affected by the toe headings. TI position produced larger valgus angle due to reduce knee distance in addition to higher flexion and valgus moment than other positions, which was somewhat vulnerable to the potential risk of non-contact ACL injury. TO position caused the largest internal rotation angle with smaller joint moments. Therefore, it is recommended that athletes need to land on the ground with neutral toe-heading position as possible in order to minimize the potential risk of non-contact ACL injury.

• Korean Journal of Applied Biomechanics
• /
• v.28 no.4
• /
• pp.199-205
• /
• 2018

Objective: The purpose of this study was to examine the effect of increase in barbell weight on closely related variable to the anterior cruciate ligament (ACL) injury which are knee joint kinematics, joint load, joint moment, and maximum load attainment point during snatch of the weight lifting. Method: The subjects of the study were 10 male Korean national weight lifting athletes (69 kg 5, 77 kg 5; age: $21.80{\pm}3.91yrs.$, height: $168.00{\pm}4.06cm$, weight: $75.00{\pm}4.02kg$, career: $7.8{\pm}3.99yrs.$, snatch records: $168{\pm}4.06kg$). The weight of the barbell during the snatch operation was set at 70%, 75% and 80% of the highest records for each subject studied. Results: The result obtained from the one-way repeated measure ANOVA are as follows: With increased barbell weight, the extension moment of the left knee joint was higher in the 80% condition than the 70% (p<.001). However, other variables were not statistically significant difference. According to the factor analysis of the variables related to maximum load attainment point of the ACL major injury variables, the first sub-factor was the internal shear force, the posterior shear force, the abduction moment, and the muscle activity of the VL. The second sub-factor was the extension moment of the knee joint, compressive force, adduction moment, and the third sub-factor was the muscle activity of BF. Conclusion: These results indicate that the possibility of ACL injury can be lowered when performing a stable snatch movement.

• Journal of the Korean Arthroscopy Society
• /
• v.10 no.1
• /
• pp.39-44
• /
• 2006

Purpose: The object of this study is to compare the Insall-Salvati ratio and Carton index between the patients who have an anterior cruciate ligament (ACL) tear and the patients who have no ACL tear. Materials and Methods: The study group included 114 patients who had an ACL tear and received arthroscopic reconstruction. The group I was acute ACL tear group, within 3 weeks after injury. The group II was chronic ACL tear group who had MRI was done after 3 weeks from injury. The group III was normal control group. We measured the Insall-Salvati ratio and Carton index on Magnetic Resonance Images (MRI) for all patients. Results: The Insall-Salvati ratio of control group was $1.02{\pm}0.12$ and Carton index of control group was $1.14{\pm}0.16$. The ACL-tear study group was $0.91{\pm}0.12\;and\;0.89{\pm}0.20$ respectively. The Insall-Salvati ratio and Caton index in ACL tear group was significantly less than those of control group. There were no significant differences in comparing with acute and chronic ACL tear group. Conclusion: Our study show that patella baja has an association with ACL tears, therefore in patients with an ACL tear who had patella baja, ideal graft for reconstruction was seriously considered.

• Advances in nano research
• /
• v.13 no.3
• /
• pp.247-257
• /
• 2022

Extraordinary properties of nanocomposites make them a primary replacement for many conventional materials. Anterior cruciate ligament (ACL) reconstruction, which is a frequent surgery in sport activities, is one of the fields in which nanocomposites could be utilized. In the present study, the mechanical properties of different porous scaffolds made from graphene nano-composites are presented ad load bearing capacity of these materials is calculated using finite element method. The numerical results are further compared with experimental published data. In addition, several geometrical and material parameters are analyzed to find the best configuration of nanocomposite scaffolds in reconstruction of ACL. Moreover, coating of detoxification chemicals are extremely easier on the nano-structured materials than conventional one. Detoxification potential of nano-composites in the injured body are also discussed in detail. The results indicated that nano-composite could be successfully used in place of auto- and allografts and also instead of conventional metallic screws in reconstruction of ACL.

• Journal of Korean Orthopaedic Sports Medicine
• /
• v.1 no.2
• /
• pp.109-114
• /
• 2002

The types of Alpine ski injuries have changed through the years in relationship to the development of skiing equipment. Modern skis, boots and bindings are better at protecting the tibia, which previously was almost as commonly injured as the knee. Since the 1980s, severe knee sprains, most of them involving the anterior cruciate ligament have tripled while injuries of the lower extremity below the knee diminished significantly. However, recent studies show no further improvements in either lower leg fractures or increase in the rates of ACL sprains has occurred. The use of carving skis presents an increased risk for sustaining isolated ACL injuries in more skilled skiers and less skilled skiers are more likely to sustain an ankle fracture than skiers using conventional skis. To restore the trend of diminishing lower leg injury rates, efforts will be needed to motivate skiers to have their equipment serviced by ski shop professionals following ASTM (American Society for Testing and Material) standard procedures. As of now, there are no boots, bindings or skis on the market designed to protect skiers from the ACL injury. The only method proven to reduce ACL injury Is a training program based on recognizing the circumstances that lead to ACL injury in skiing and to avoid these events.

• Journal of the Korean Arthroscopy Society
• /
• v.6 no.2
• /
• pp.109-114
• /
• 2002

Propose : The purpose of this retrospective study was to test the posterior cruciate ligament (PCL index) for diagnosis of a tear of the anterior cruciate ligament (ACL) by means of MR imaging. Materials and Methods : From Mar. 1997 to Feb. 2001, concomitant magnetic resonance imaging (MRI) and knee joint arthroscopy were performed in 56 patients of either pain or instability of the knee. The shortest distance between the femoral and tibial attachment of PCL (X) and the distance from that line to the tip of the arc marked by the PCL (Y) on the sagittal plane images were measured. The quotient of these two parameters (Y/X) defined the PCL index. Results : Using MRI diagnosis, there were 35 patients diagnosed with ACL rupture and 21 patients were ruled out of ACL injury. Using arthroscopy, 32 of the 35 patients diagnosed by MRI showed ACL rupture, and 20 of the 21 patients were ruled out of ACL injury. The mean PCL index was 0.40 in the 33 patients diagnosed with ACL rupture through arthroscopy. The mean PCL index was 0.23 in 23 patients with an uninjured ACL through arthroscopy. In 33 patients with ruptured ACL, this value exceeds 0.31. The index value was 0.31 in 3 patients with uninjured ACL. The value of the index was not above 0.31 with an uninjured ACL. PCL index on MRI had a sensitivity of $91\%$ and a specificity of $94\%$ for determining the status of the anterior cruciate ligament. Conclusion : Injury to the ACL changes the PCL index markedly. In diagnostically unreliable MR images, amelioration of the PCL index could help in the diagnosis of ACL injury.

• Journal of the Korean Arthroscopy Society
• /
• v.9 no.1
• /
• pp.46-50
• /
• 2005

Purpose: The purpose of this study is to evaluate the accuracy of magnetic resonance imaging (MRI) in the diagnosis of acute anterior cruciate ligament (ACL) injury and its tear pattern in comparison with arthroscopic finding. Materials and Methods: Sixty consecutive patients with acute ACL injury were taken NRI followed by arthroscopic examination between January 2002 and June 2004. MRI findings were reviewed according to the presence of ACL discontinuity, diffuse swelling or thickening, focal edema, collapse on distal end, and any combined tear. The pathologic findings were then confirmed arthroscopically. The diagnostic accuracy of MRI on ACL tear pattern was analyzed by obtaining its positive predictive value. Results: All fifty two cases with presence of discontinuity on MRI showed ACL rupture arthroscopically. The location of ACL tear, diffuse swelling and focal edema on MRI also corresponded with arthroscopic findings respectively. However, the diagnostic accuracy of MRI was relatively lower in the presence of other ACL patterns such as collapses and combined tear. Conclusion: Preoperative MRI findings seem to be in accordance with arthroscopic findings and is significantly accurate in detection of location and diffuse swelling and focal edema of ACL tear.

• Journal of the Korean Orthopaedic Association
• /
• v.55 no.5
• /
• pp.444-449
• /
• 2020

An anterior cruciate ligament (ACL) avulsion fracture is an uncommon injury that occurs predominantly in the pediatric and adolescent population. Accurate reduction and fixation of an avulsed fragment are necessary to restore and maintain the length of the ACL and normal knee biomechanics. Several techniques are available to repair an ACL avulsion fracture. On the other hand, treatment is controversial in skeletally immature patients due to risk of physeal injury. This paper reports a case of an ACL avulsed fracture in a skeletally immature patient treated with arthroscopic all-inside suture bridge repair, in which an excellent result and firm stability were obtained without physeal injury.

• Journal of the Korean Arthroscopy Society
• /
• v.1 no.1
• /
• pp.112-115
• /
• 1997

While the cruciate ligament has a profuse vascular response following injury, spontaneous repair does not occur. This may result from the fact that synovial fluid dilution of the hematoma following injury prevents the formation of a fibrin clot and thus the initiation of the healing mechanism. Another theory suggests that the dynamic nature of the fascicles of the anterior cruciate ligament(ACL) through even small ranges of motion prohibits spontaneous union to these fibers. But we experienced two cases of spontaneous healing of partially injured ACL. Initially they showed more than grade II anterior instability. 6 mm difference by stress roentgenographs(pull view) and difference of 8 mm by KT 1000TM arthrometer between the ACL injured knee and normal side knee. Lax, nearly complete tear of ACL and synovial bleeding were noted during arthroscopic examination but the continuity of synovial membrane was seemed to be intact. These cases were treated by conservative management rather than reconstructive procedure. Postoperatively they showed excellent clinical results, no anterior instability and unlimited athletic activity. Based on our clinical experience. we think that cruciate ligament has the spontaneous healing potential in acute stage and middle aged patient. We consider the microfracture technique and initial immobilization for accelleration of healing response of the ACL.