BACKGROUND Recently,the use of ligament advanced reinforcement system(LARS)artificial ligament,a new graft which has several unique advantages such as no donor-site morbidity,early recovery and no risk of disease tran...BACKGROUND Recently,the use of ligament advanced reinforcement system(LARS)artificial ligament,a new graft which has several unique advantages such as no donor-site morbidity,early recovery and no risk of disease transmission which has been a significant breakthrough for anatomical ligament reconstruction.Growing studies suggested that the special design of the LARS ligament with open fibers in its intra-articular part was believed to be more resistant to torsional fatigue and wearing.However,the safety and efficacy of LARS artificial ligament for ankle joint lateral collateral ankle ligament reconstruction has not been defined to date.AIM To evaluate the clinical results of all-arthroscopic anatomical reconstruction of ankle joint lateral collateral ligaments with the LARS artificial ligament for chronic ankle instability.METHODS Twenty-two patients with chronic lateral instability underwent anatomical reconstruction of the lateral collateral ligaments of ankle with LARS artificial ligament.The visual analogue score(VAS),American Orthopaedic Foot and Ankle Society score(AOFAS score)and Karlsson score were used to evaluate the clinical results before and after surgery.RESULTS A total of 22 patients(22 ankles)were followed up for a mean of 12 mo.All patients reported significant improvement compared to their preoperative status.The mean AOFAS score improved from 42.3±4.9 preoperatively to 90.4±6.7 postoperatively.The mean Karlsson score improved from 38.5±3.2 preoperatively to 90.1±7.8 postoperatively.The mean VAS score improved from 1.9±2.5 preoperatively to 0.8±1.7 postoperatively.CONCLUSION All-arthroscopic anatomical reconstruction of the lateral collateral ligaments with LARS artificial ligament achieved a satisfactory surgical outcome for chronic ankle instability.展开更多
<span style="font-family:Verdana;">This study aimed to evaluate the influence of measuring the length of the medial collateral ligament (MCL) to compare the MCL burden when the knee joint is placed und...<span style="font-family:Verdana;">This study aimed to evaluate the influence of measuring the length of the medial collateral ligament (MCL) to compare the MCL burden when the knee joint is placed under valgus stress in the open and closed and closed kinetic chain.</span><b> </b><span style="font-family:Verdana;">Two examiners conducted the examination. The MCL length was measured using ultrasonography. Two subjects were measured in unload bearing and load-bearing positions, with and without valgus stress test at the knee joint extension and 30<span style="white-space:nowrap;">°</span> flexion, under eight different measurement conditions. The MCL of the subject was delineated in the longitudinal direction using an ultrasound system. The attachment points of the medial femoral and tibial condyle of the MCL were identified, and the ligament length was measured. The MCL rate before and after the valgus stress test in the loading and unloading positions was calculated.</span><b> </b><span style="font-family:Verdana;">The MCL length increased by an average of 8.9% when the external stress test was performed in the non-weight bearing and knee extension positions and by an average of 17.0% when external stress was applied in the non-weight bearing and knee flexion positions. The MCL length increased by an average of 12.2% when the external stress test was performed in the load-bearing and knee extension positions and an average of 8.9% when the valgus stress test was applied in load-bearing and knee flexion positions. In conclusion, the effect of valgus stress on the MCL differs between load-bearing and non-load-bearing positions. It is considered that the dynamic stabilization mechanism works in the knee joint flexion position in the load position and works simultaneously as the static stabilization mechanism, which limits the knee joint valgus and reduces the extension rate of MCL. Therefore, this study reconsiders the shifting of traditional therapy from open kinetic chain to close kinetic chain.</span>展开更多
In the rare cases with serious damage of the Medial Collateral Ligament (MCL) of the knee requiring surgical treatment, ligament remnants may be inadequate for a good repair. In such cases, reconstruction should be pe...In the rare cases with serious damage of the Medial Collateral Ligament (MCL) of the knee requiring surgical treatment, ligament remnants may be inadequate for a good repair. In such cases, reconstruction should be performed and technical options may be limited. We used an Achilles tendon allograft and applied it using the Pulvertaft weave technique for tendon repair. We found no previous reports of allograft application for MCL repair though the technique has been extensively used for Anterior Cruciate Ligament reconstruction.展开更多
The association between injuries to the anterior cruciate ligament,medial collateral ligament,and medial meniscus(MM)has been known to orthopedic surgeons since 1936;O’Donoghue first used the term"unhappy triad&...The association between injuries to the anterior cruciate ligament,medial collateral ligament,and medial meniscus(MM)has been known to orthopedic surgeons since 1936;O’Donoghue first used the term"unhappy triad"of the knee to describe this condition in 1950.Later studies revealed that involvement of the lateral meniscus is more common than MM in these cases,leading to a change in the definition.Recent studies have revealed that this triad may be primarily linked to knee anterolateral complex injuries.Although there is not a definite management protocol for this triad,we try to mention the most recent concepts about it in addition to expert opinions.展开更多
BACKGROUND Simple lateral elbow dislocation(SLED)is a rare type of elbow dislocation;however,its treatment may be complicated by accompanying soft tissue or neurovascular damage.Herein,we report a rare case of SLED ma...BACKGROUND Simple lateral elbow dislocation(SLED)is a rare type of elbow dislocation;however,its treatment may be complicated by accompanying soft tissue or neurovascular damage.Herein,we report a rare case of SLED managed secondarily with open reduction and soft tissue repair following failure of closed reduction.CASE SUMMARY A 67-year-old woman suffered SLED after falling on her outstretched left hand with her elbow extended.She developed pain,swelling,and movement restriction in the elbow;there were no neurovascular symptoms,except for numbness in the 4th and 5th digits.Radiologic investigation confirmed the SLED,and a closed reduction under anesthesia was performed.The follow-up radiographs at 1-wk revealed failure of reduction;accordingly,open reduction with lateral collateral ligament and common extensor origin repair were carried out.The patient regained full elbow range of motion by six weeks.CONCLUSION Adequate concentric reduction for SLED,conservatively or surgically,reduces complications and provides a more functional joint.展开更多
The importance of ligaments in providing joint stability and the incidence of injuries, dictates a need to increase their structural and mechanical properties understanding. Additionally, one of the challenges in the ...The importance of ligaments in providing joint stability and the incidence of injuries, dictates a need to increase their structural and mechanical properties understanding. Additionally, one of the challenges in the orthopedic industry is to design TKA (total knee arthroplasty) aiming to be soft-tissues friendly. This requires a priori knowledge of physiological knee function, in which the passive stability is achieved and guaranteed by the complex envelope of soft tissues around the joint. Therefore, the knowledge of the mechanical behavior of knee ligaments is fundamental. For this reason, our study aims to define and apply in a pilot study, an ad-hoc methodology to mechanically characterize ligaments of native human knees. The cruciate and collateral ligaments from a fresh frozen cadaver leg were accurately harvested. Each ligament was independently tested during a tensile test at different strain rates, simulating different deformation speeds during gait. Moreover, additional tensile tests until failure were also performed. Axial force and deformation were continuously recorded during each test. Results show that each ligament exhibited own typical non-linear, speed-related behavior. High repeatability in the results is observed among the different repeated tests confirming the robustness of the used methodology. This information will be helpful for clinicians, engineers and researchers to improve the biomechanical knowledge about knee, to develop better implants and to be able to improve the currently available numerical models of the human knee.展开更多
Objective: To create a 3-dimensional finite element model of knee ligaments and to analyse the stress changes of lateral collateral ligament (LCL) with or without displaced movements at different knee flexion condi...Objective: To create a 3-dimensional finite element model of knee ligaments and to analyse the stress changes of lateral collateral ligament (LCL) with or without displaced movements at different knee flexion conditions. Methods: A four-major-ligament contained knee specimen from an adult died of skull injury was prepared for CT scanning with the detectable ligament insertion footprints, locations and orientations precisely marked in advance. The CT scanning images were converted to a 3-dimensional model of the knee with the 3-dimensional reconstruction technique and transformed into finite element model by the software of ANSYS. The model was validated using experimental and numerical results obtained by other scientists. The natural stress changes of LCL at five different knee flexion angles (0°, 30°60°, 90°, 120°) and under various motions of anterior-posterior tibial translation, tibial varus rotation and internal-external tibial rotation were measured. Results: The maximum stress reached to 87%-113% versus natural stress in varus motion at early 30° of knee flexions. The stress values were smaller than the peak value of natural stress at 0° (knee full extension) when knee bending was over 60° of flexion in anterior-posterior tibial translation and internal-external rotation. Conclusion: LCL is vulnerable to varus motion in almost all knee bending positions and susceptible to ante- rior-posterior tibial translation or internal-external rotation at early 30° of knee flexions.展开更多
文摘BACKGROUND Recently,the use of ligament advanced reinforcement system(LARS)artificial ligament,a new graft which has several unique advantages such as no donor-site morbidity,early recovery and no risk of disease transmission which has been a significant breakthrough for anatomical ligament reconstruction.Growing studies suggested that the special design of the LARS ligament with open fibers in its intra-articular part was believed to be more resistant to torsional fatigue and wearing.However,the safety and efficacy of LARS artificial ligament for ankle joint lateral collateral ankle ligament reconstruction has not been defined to date.AIM To evaluate the clinical results of all-arthroscopic anatomical reconstruction of ankle joint lateral collateral ligaments with the LARS artificial ligament for chronic ankle instability.METHODS Twenty-two patients with chronic lateral instability underwent anatomical reconstruction of the lateral collateral ligaments of ankle with LARS artificial ligament.The visual analogue score(VAS),American Orthopaedic Foot and Ankle Society score(AOFAS score)and Karlsson score were used to evaluate the clinical results before and after surgery.RESULTS A total of 22 patients(22 ankles)were followed up for a mean of 12 mo.All patients reported significant improvement compared to their preoperative status.The mean AOFAS score improved from 42.3±4.9 preoperatively to 90.4±6.7 postoperatively.The mean Karlsson score improved from 38.5±3.2 preoperatively to 90.1±7.8 postoperatively.The mean VAS score improved from 1.9±2.5 preoperatively to 0.8±1.7 postoperatively.CONCLUSION All-arthroscopic anatomical reconstruction of the lateral collateral ligaments with LARS artificial ligament achieved a satisfactory surgical outcome for chronic ankle instability.
文摘<span style="font-family:Verdana;">This study aimed to evaluate the influence of measuring the length of the medial collateral ligament (MCL) to compare the MCL burden when the knee joint is placed under valgus stress in the open and closed and closed kinetic chain.</span><b> </b><span style="font-family:Verdana;">Two examiners conducted the examination. The MCL length was measured using ultrasonography. Two subjects were measured in unload bearing and load-bearing positions, with and without valgus stress test at the knee joint extension and 30<span style="white-space:nowrap;">°</span> flexion, under eight different measurement conditions. The MCL of the subject was delineated in the longitudinal direction using an ultrasound system. The attachment points of the medial femoral and tibial condyle of the MCL were identified, and the ligament length was measured. The MCL rate before and after the valgus stress test in the loading and unloading positions was calculated.</span><b> </b><span style="font-family:Verdana;">The MCL length increased by an average of 8.9% when the external stress test was performed in the non-weight bearing and knee extension positions and by an average of 17.0% when external stress was applied in the non-weight bearing and knee flexion positions. The MCL length increased by an average of 12.2% when the external stress test was performed in the load-bearing and knee extension positions and an average of 8.9% when the valgus stress test was applied in load-bearing and knee flexion positions. In conclusion, the effect of valgus stress on the MCL differs between load-bearing and non-load-bearing positions. It is considered that the dynamic stabilization mechanism works in the knee joint flexion position in the load position and works simultaneously as the static stabilization mechanism, which limits the knee joint valgus and reduces the extension rate of MCL. Therefore, this study reconsiders the shifting of traditional therapy from open kinetic chain to close kinetic chain.</span>
文摘In the rare cases with serious damage of the Medial Collateral Ligament (MCL) of the knee requiring surgical treatment, ligament remnants may be inadequate for a good repair. In such cases, reconstruction should be performed and technical options may be limited. We used an Achilles tendon allograft and applied it using the Pulvertaft weave technique for tendon repair. We found no previous reports of allograft application for MCL repair though the technique has been extensively used for Anterior Cruciate Ligament reconstruction.
文摘The association between injuries to the anterior cruciate ligament,medial collateral ligament,and medial meniscus(MM)has been known to orthopedic surgeons since 1936;O’Donoghue first used the term"unhappy triad"of the knee to describe this condition in 1950.Later studies revealed that involvement of the lateral meniscus is more common than MM in these cases,leading to a change in the definition.Recent studies have revealed that this triad may be primarily linked to knee anterolateral complex injuries.Although there is not a definite management protocol for this triad,we try to mention the most recent concepts about it in addition to expert opinions.
文摘BACKGROUND Simple lateral elbow dislocation(SLED)is a rare type of elbow dislocation;however,its treatment may be complicated by accompanying soft tissue or neurovascular damage.Herein,we report a rare case of SLED managed secondarily with open reduction and soft tissue repair following failure of closed reduction.CASE SUMMARY A 67-year-old woman suffered SLED after falling on her outstretched left hand with her elbow extended.She developed pain,swelling,and movement restriction in the elbow;there were no neurovascular symptoms,except for numbness in the 4th and 5th digits.Radiologic investigation confirmed the SLED,and a closed reduction under anesthesia was performed.The follow-up radiographs at 1-wk revealed failure of reduction;accordingly,open reduction with lateral collateral ligament and common extensor origin repair were carried out.The patient regained full elbow range of motion by six weeks.CONCLUSION Adequate concentric reduction for SLED,conservatively or surgically,reduces complications and provides a more functional joint.
文摘The importance of ligaments in providing joint stability and the incidence of injuries, dictates a need to increase their structural and mechanical properties understanding. Additionally, one of the challenges in the orthopedic industry is to design TKA (total knee arthroplasty) aiming to be soft-tissues friendly. This requires a priori knowledge of physiological knee function, in which the passive stability is achieved and guaranteed by the complex envelope of soft tissues around the joint. Therefore, the knowledge of the mechanical behavior of knee ligaments is fundamental. For this reason, our study aims to define and apply in a pilot study, an ad-hoc methodology to mechanically characterize ligaments of native human knees. The cruciate and collateral ligaments from a fresh frozen cadaver leg were accurately harvested. Each ligament was independently tested during a tensile test at different strain rates, simulating different deformation speeds during gait. Moreover, additional tensile tests until failure were also performed. Axial force and deformation were continuously recorded during each test. Results show that each ligament exhibited own typical non-linear, speed-related behavior. High repeatability in the results is observed among the different repeated tests confirming the robustness of the used methodology. This information will be helpful for clinicians, engineers and researchers to improve the biomechanical knowledge about knee, to develop better implants and to be able to improve the currently available numerical models of the human knee.
文摘Objective: To create a 3-dimensional finite element model of knee ligaments and to analyse the stress changes of lateral collateral ligament (LCL) with or without displaced movements at different knee flexion conditions. Methods: A four-major-ligament contained knee specimen from an adult died of skull injury was prepared for CT scanning with the detectable ligament insertion footprints, locations and orientations precisely marked in advance. The CT scanning images were converted to a 3-dimensional model of the knee with the 3-dimensional reconstruction technique and transformed into finite element model by the software of ANSYS. The model was validated using experimental and numerical results obtained by other scientists. The natural stress changes of LCL at five different knee flexion angles (0°, 30°60°, 90°, 120°) and under various motions of anterior-posterior tibial translation, tibial varus rotation and internal-external tibial rotation were measured. Results: The maximum stress reached to 87%-113% versus natural stress in varus motion at early 30° of knee flexions. The stress values were smaller than the peak value of natural stress at 0° (knee full extension) when knee bending was over 60° of flexion in anterior-posterior tibial translation and internal-external rotation. Conclusion: LCL is vulnerable to varus motion in almost all knee bending positions and susceptible to ante- rior-posterior tibial translation or internal-external rotation at early 30° of knee flexions.