Multiligament knee injuries with associated tibial plateau fractures: A report of two cases

The management of a combination of fracture and multiligament knee injury(MKI) in traumatic knee injury remains controversial, and there are evolving treatment recommendations. Currently, there are no studies focusing on older adult patients with MKI's in combination with tibia fractures. As a result, there is no well-established treatment algorithm for older adult patients with these complex injuries. We report two cases of MKI's with concomitant fractures in patients fifty years of age or older. Both patients were treated surgically for their associated tibial plateau fractures, but were managed with conservative treatment of the multiligamentous knee injuries. We also provide a review of the literature and guidelines for older adult patients with these types of complex traumatic injuries. Early to mid term acceptable outcomes were achieved for both patients through surgical fixation of the tibial plateau fracture and conservative treatment of the ligament injuries. We propose a comprehensive treatment algorithm for management of these complex injuries.

Complex knee injuries treated in acute phase: Long-term results using Ligament Augmentation and Reconstruction System artificial ligament

AIM To present the long-term results of complex knee injuries, treated early using the Ligament Augmentation and Reconstruction System(LARS) artificial ligament to reconstruct posterior cruciate ligament(PCL).METHODS From September 1997 to June 2010, thirty-eight complex knee injuries were treated, where early arthroscopic PCL reconstructions were undergone, using the LARS(Surgical Implants and Devices, Arc-sur-Tille, France) artificial ligament. Exclusion criteria were: Late(> 4 wk) reconstruction, open technique, isolated PCL reconstruction, knee degenerative disease, combinedfracture or vascular injury and use of allograft or autograft for PCL reconstruction. Clinical and functional outcomes were assessed with IKDC Subjective Knee Form, KOS-ADLS questionnaire, Lysholm scale and SF-12 Health Survey. Posterior displacement(PD) was measured with the Telos Stress Device. RESULTS Seven patients were excluded; two because of coexisting knee osteoarthritis and the remaining five because of failure to attend the final follow-up. The sample consisted of 31 patients with mean age at the time of reconstruction 33.2 ± 12.5 years(range 17-61). The postoperative follow-up was on average 9.27 ± 4.27 years(range 5-18). The mean average IKDC and KOS scores were 79.32 ± 17.1 and 88.1 ± 12.47% respectively. Average PD was 3.61 ± 2.15 mm compared to 0.91 ± 1.17 mm in the uninjured knees(one with grade 1+ and two with grade 2 +). Dial test was found positive in one patient, whereas the quadriceps active drawer test was positive in three patients. None was tested positive on the reverse-pivot shift test. The range of motion(ROM) was normal in thirty knees, in comparison with the contralateral one. There was no extension deficit. Osteoarthritic changes were found in three knees(9.6%).CONCLUSION Early treatment of complex knee injuries, using LARS artificial ligament for PCL reconstruction sufficiently reduces posterior tibia displacement and provides satisfactory long-term functional outcomes.

A Mesh Meta-Analysis of the Effectiveness of Different Warm-Up Exercises to Prevent Knee Injuries in Young Child Soccer Players

Objective: A mesh Meta-analysis was used to evaluate the effectiveness of four warm-up exercises to prevent knee injuries in juvenile soccer players. Method: They are a randomized controlled trial (RCT) on FIFA 11+ integrated warm-up, FIFA 11+ Kids integrated warm-up, and neuromuscular training (NMT) warm-up for the prevention of knee joint in juvenile soccer players by a computer search of CNKI, CBMdisc, WanFangdata, Pubmed, Web of science, and SPORTDicus database. The search period was from the establishment of each database to February 2022. Two investigators screened the literature, extracted data, and assessed risk bias for the included studies according to the pre-defined inclusion and exclusion criteria, and finally analyzed the data using Stata 14.0 software and OpenBUGS software. Results: A total of 10 RCT studies with 17,143 subjects, spanning the age range of 7 to 19 years, were included. The results of the reticulated Meta-analysis showed that all three warm-up modalities were effective in reducing the incidence of knee injuries in junior soccer players compared to conventional warm-up, with the optimality in descending order of FIFA 11+ Kids comprehensive warm-up (SUCRA = 85.3), neuromuscular training warm-up (SUCRA = 66.7), and FIFA 11+ combined warm-up (SUCRA = 44). Conclusion: The FIFA 11+ Kids comprehensive warm-up is the most effective warm-up exercise for the prevention of knee injuries in junior and child soccer players, but the above findings need further validation due to the quantity and quality of the literature and the quality of the evidence.

Functional Outcomes for Combined Acute Anterior and Posterior Cruciate Knee Injuries Treated Non-Operatively

Introduction: results after non-operative management for knees sustaining combined acute anterior and posterior cruciate ligament tears were presented. Subjects: 13 patients, 10 with medial, and 3 with lateral ligament injury. Methods: non-operative management consisted of employing a brace to prevent sagittal translation of the tibia. Quadriceps muscle and early passive knee motion exercises in the brace was encouraged immediately after arthroscopy. Weight-bearing was forbidden for 3 weeks. The brace was not removed for 3 months. Follow-up periods ranged from 2 to 6 years (mean, 3 years 2 months). Results: none, but one patient had a slight restriction of knee flexion. Quadriceps muscle strength revealed an average of 89.0% of normal side. The knee score indicated 2 patients rated good, 3 rated fair, and 8 rated poor. The score correlated with measurements of anterior and posterior translation on the stress radiograph significantly. Stress radiography revealed that anterior laxity was reduced better than posterior laxity significantly. Conclusion: non-operative brace therapy can be considered for this combined injury as the initial treatment. A late reconstruction would be performed when the result was not satisfactory. Preserved range of motion and muscle strength after brace therapy had a great advantage to the late reconstructive surgery.

3D Finite Element Model of Human Knee Injuries in the Traffic Accident

Objective To explore the injury mechanism of the human knee in a traffic accident by establishing a 3D finite element(FE) model. Methods The FE model, composed of femur, tibia, fibula, patella, meniscus, knee ligaments and surrounding soft tissues, was reconstructed by CT scanning data from a male volunteer. Validation was performed by the lateral impact simulation, and the stress and strain results were obtained to be compared with those previously reported for injury prediction. Results The results derived from the FE model were found to be similar with those previously reported, most of the ligaments and meniscus wounded at 40 m/s collision, which was readily observed. Conclusion The simulation results generated by FE model can be effectively used for the injury mechanism analysis of initial contact.

Injuries in Spanish female soccer players

Background: Epidemiologic research to learn the incidence, type, location, and severity of female soccer injuries and the risk factors for sustaining a sport injury is the first step in developing preventive policies. The aim of this study was to analyze the incidence of injuries in the population of female soccer players in Spain.Methods: The injuries incurred by 25,397 female soccer players were registered by the medical staff of the Spanish Football Federation during 1 season. A standardized medical questionnaire was used to classify the injury according to type, severity, location, and injury mechanism. A total of 2108 injuries was reported with an incidence of 0.083 injuries per player per season. Most injuries were in the lower limbs(74.0%), mainly affecting knee(30.4%) and ankle joints(17.9%).Results: The proportion of injuries derived from contact with another player was higher during matches(33.7%) than during training(11.4%;p < 0.001). Noncontact injuries were classified as severe more frequently than were contact injuries(51.0% vs. 42.6%; p < 0.001). A higher incidence of injury was found in adult soccer players(≥18 years) vs. their counterparts younger than 18 years(0.094 vs. 0.072 injuries per player per year, respectively; p < 0.001). There were no differences between age groups in any other injury variable(e.g., type, mechanism, location, or severity; p > 0.05).Conclusion: Most female soccer injuries were located at the knee and ankle; the injury mechanism determined the playing time lost; and the player's age did not affect injury characteristics.

Consensus Delphi study on guidelines for the assessment of anterior cruciate ligament injuries in children

Background:Knee examination guidelines in minors are intended to aid decisionmaking in the management of knee instability.Clinical question:A Delphi study was conducted with a formal consensus process using a validated methodology with sufficient scientific evidence.A group consensus meeting was held to develop recommendations and practical guidelines for use in the assessment of instability injuries in children.Key findings:there is a lack of evidence to analyse anterior cruciate ligament injuries in children and their subsequent surgical management if necessary.Diagnostic guidelines and clinical assessment of the patient based on a thorough examination of the knee are performed and a guide to anterior cruciate ligament exploration in children is developed.Clinical application:In the absence of a strong evidence base,these established guidelines are intended to assist in that decision-making process to help the clinician decide on the most optimal treatment with the aim of benefiting the patient as much as possible.Following this expert consensus,surgical treatment is advised when the patient has a subjective sensation of instability accompanied by a pivot shift test++,and may include an anterior drawer test+and a Lachman test+.If these conditions are not present,the conservative approach should be chosen,as the anatomical and functional development of children,together with a physiotherapy programme,may improve the evolution of the injury.

Injuries Requiring Surgery in Folk Dancers： A Retrospective Cohort Study of 9 Years

Background： In this study, we examined professional folk dancer injuries which required surgery and if there are any associated factors like age, gender, dexterity, dance style and to evaluate the return to their full capacity. Materials and Methods： Seventy five members of the Fire of Anatolia dance group （mean age： 26.8 ± 5.2; 18-38 years） performers were evaluated. The dancers suffered 14 orthopedic injuries requiring surgery （3 meniscus tears, 2 anterior cruciate ligament tears one of which is with posterolateral corner tear, 1 posterior cruciate ligament tear, 1 patellar dislocation, 1 scaphoid fracture, 1 extensor tendon cut in hand, 1 infrapatellar bursitis, 2 Hoffa’s fat pad syndromes, 2 symptomatic medial plicaes） during a nine-year period. Follow-up time was 51 ± 41.9 （29.5-92） months. Results： Following surgeries, the dancers could restart rehearsals in 12.7 ± 9 （range： 4 to 36） weeks and perform live on the stage in 16.2 ± 12.2 （range： 5 to 52） weeks on average. Conclusion： Males were 8.64 times more likely to suffer an injury requiring surgery compared to the females （p = 0.003） and twelve （85.7%） of these injuries were lower extremity injuries and were all located in the knee in Anatolian folk dancers.

Commentary on“The deterministic condition for the ground reaction force acting point on the combined knee valgus and tibial internal rotation moments in the early phase of cutting maneuvers in female athletes”

1.Introduction For decades,substantial disagreement has persisted as to whether dynamic knee valgus is the cause of the majority of anterior cruciate ligament(ACL)injuries or rather the result of the ACL rupture.1 Consequently,great effort and expense has gone into capturing 3-dimensional kinetics and kinematics from live athletes to drive in vitro and in silico models of ACL injury in order to elucidate the actual mechanism of injury,as these factors have been demonstrated to be surrogates of intraarticular structural loading on the ACL.2,3 The elucidation of injury mechanisms for non-contact ACL injuries is of great medical value as such knowledge consequently permits quantified examination and validation of interventions and their respective effectiveness in both prevention and rehabilitation of these traumatic knee injuries.

Effect of sodium hyaluronate combined with rehabilitation training on knee joint injury caused by golf

BACKGROUND In high-intensity sports like golf,knee joints are prone to injury,leading to pain,limited mobility,and decreased quality of life.Traditional treatment methods typically involve rehabilitation exercises,but their effectiveness may be limited.In recent years,sodium hyaluronate has emerged as a widely used biomedical material in the treatment of joint diseases.AIM To explore the effect of sodium hyaluronate combined with rehabilitation training on pain degree,flexion range of motion and motor function of knee joint injured by golf.METHODS Eighty patients with knee joint injury caused by golf were randomly divided into control(group B)and observation group(group A).The group B was treated with rehabilitation training,and the group A was treated with sodium hyaluronate combined with rehabilitation training.The clinical efficacy,range of motion and function of knee joint,quality of life and inflammatory factors were compared.RESULTS The excellent and good rate of rehabilitation in the group A was raised than group B.At 6 weeks and 3 months after treatment,the range of motion of the two groups was raised than that before treatment,and that of the group A was raised than group B.After treatment,the scores of Lysholm and International Knee Documentation Committee(IKDC)in the group A were raised,and those in the group A were raised than group B.The VAS score of the two groups was reduced than that of the group B,and the SF-36 score of the group A was reduced than group B.The interleukin(IL)-1β,IL-8 and tumor necrosis factor-αin the two groups were reduced,and those in the group A were reduced than group B.CONCLUSION Sodium hyaluronate combined with rehabilitation training has a good clinical effect in the treatment of patients with knee joint injury caused by golf,which relieve pain,maintain knee joint function and improve patients'life quality.

不同月龄豚鼠自发膝骨关节炎过程中全膝关节的病理变化

背景:豚鼠因具有与人类相似的膝关节结构和接近的组织病理学特征,被认为是最有助于评估人类原发性骨关节炎的自发模型。目的:通过对1-18月龄豚鼠的全膝关节组织病理学分析,探讨豚鼠自发膝骨关节炎的病理过程。方法:选取健康1,6,10,14,16,18月龄Hartley雌性豚鼠各8只,将股四头肌进行苏木精-伊红染色,整体膝关节进行苏木精-伊红染色和甲苯胺蓝染色,在光镜下观察软骨、软骨下骨、滑膜、半月板、肌肉的组织病理学情况,进行关节软骨Mankin评分和滑膜炎评分,并进行二者的相关性分析。结果与结论:(1)随着豚鼠月龄的增长,关节软骨Mankin评分越高(P<0.05),滑膜炎病理评分也逐渐增高(P<0.05),且二者之间存在显著正相关(r=0.641,P<0.001);(2)18月龄豚鼠软骨下骨骨髓病变发病率达50%,半月板损伤发生率达37.5%;且出现不同程度的骨赘和关节间隙变窄等病变,仅有少数豚鼠出现股四头肌肉炎症;(3)结果说明豚鼠随着年龄增长,出现明显的软骨缺损、滑膜炎症、软骨下骨病变、半月板损伤、骨赘形成和关节间隙变窄等,均与人类原发性膝骨关节炎的病理过程相似,是理想的自发性膝骨关节炎模型。

下肢重复蹬伸至力竭过程中肌肉功能网络拓扑特性

背景:表面肌电已经被广泛用于监测肌肉疲劳,但传统肌电指标通常针对于单块肌肉,无法评价一组肌肉在疲劳过程中的变化。目的:建立肌肉功能网络,提取复杂网络参数,研究不同疲劳程度下的肌肉功能网络拓扑特性变化,为疲劳的监测、预防提供理论和方法依据。方法:11名受试者进行直到力竭的50%1RM单腿下肢蹬伸运动,同步采集股直肌、股外侧肌、股内侧肌、股二头肌长头、胫骨前肌、腓肠肌外侧肌、腓肠肌内侧肌7块肌肉的肌电信号,以及心电信号和Borg CR-10量表评分;根据Borg CR-10量表评分划分为轻度、中度和重度三个疲劳阶段,采用心率和心率变异性验证疲劳阶段划分的有效性;以7块肌肉为节点,使用肌肉信号的相干性构建肌肉功能网络,提取聚类系数、平均加权度、全局效率、特征向量中心性4个复杂网络参数;提取肌电信号的均方值振幅、中位频率、瞬时平均频率和共激活比4种指标,并在3种疲劳程度下进行比较。结果与结论:①3种疲劳阶段在心率及心率变异性上产生显著性差异,证明了疲劳阶段划分的有效性;②对于不同肌肉在3种疲劳程度下的肌电指标:均方值振幅和共激活比未表现出差异,中位频率在股外侧肌、股内侧肌和股二头肌长头表现出稳健的疲劳趋势,瞬时平均频率则在股直肌、股外侧肌、股内侧肌和股二头肌长头表现出稳健的疲劳趋势;瞬时平均频率的性能优于中位频率和均方值振幅,但三者仅在主要工作肌群能够获得较好的稳健趋势,共激活比不受疲劳因素的影响;③股外侧肌-股内侧肌、股外侧肌-股二头肌长头、股外侧肌-腓肠肌内侧肌和股内侧肌-股二头肌长头连接强度逐渐增加,平均加权度、聚类系数和全局效率在疲劳后表现出显著差异,并且与疲劳程度之间显著相关。结果表明:肌肉功能网络内的连通强度变化能够反映疲劳过程中肌肉间的协同性和互补性;聚类系数、平均加权度、全局效率可作为一组肌肉疲劳的监测指标。

Hemin调控小鼠软骨细胞氧化应激的线粒体途径

背景:研究显示线粒体氧化应激在膝骨关节炎发生发展中具有重要作用,Hemin可以调控线粒体相关蛋白的表达。目的:研究Hemin对小鼠软骨细胞氧化应激的调控及其在膝骨关节炎中的干预作用及机制。方法:①体外细胞实验:提取C57BL/6小鼠的原代软骨细胞,采用10 ng/mL的白细胞介素1β诱导构建体外骨关节炎软骨细胞模型,使用CCK-8法确定Hemin(0,1,10,20,40,80,160μmol/L)干预小鼠软骨细胞的最适浓度。将软骨细胞随机分为正常组、模型组(白细胞介素1β)、Hemin组(白细胞介素1β+Hemin)。检测各组软骨细胞的活性氧、线粒体膜电位和凋亡情况。②动物体内实验:将成年C57BL/6小鼠随机分为正常组、模型组(骨关节炎),Hemin(骨关节炎+Hemin)组,每组8只,Hemin治疗4周后观察小动物行为学及膝关节病理组织形态学变化,检测软骨组织细胞外基质相关蛋白表达及软骨组织细胞凋亡的变化,检测软骨组织Nrf2/HO-1蛋白的表达水平。结果与结论:①体外细胞实验:Hemin作用于原代软骨细胞的最适浓度为40μmol/L,经过Hemin处理的白细胞介素1β诱导的软骨细胞相对于模型组活性氧水平明显较少,线粒体膜电位明显有改善,软骨细胞凋亡减少。②动物体内实验:Hemin治疗4周后,与模型组比较,Hemin组的小鼠下肢功能明显转好,组织病理学评分显著改善,膝关节软骨细胞凋亡明显减少。③结果表明,Hemin可以缓解白细胞介素1β诱导下的小鼠软骨细胞氧化应激,恢复线粒体功能,减少细胞凋亡。Hemin可以改善膝骨关节炎细胞外基质降解、促进软骨细胞合成代谢、降低分解代谢及减少软骨细胞凋亡,可能是通过激活炎症环境中软骨细胞Nrf2/HO-1信号通路发挥的作用。

Elevated levels of interleukin-1β, interleukin-6, tumor necrosis factor-α and vascular endothelial growth factor in patients with knee articular cartilage injury

BACKGROUND Inflammatory cytokines play a vital role in the occurrence of osteoarticular injury and inflammation. Whether inflammation-associated factors interleukin-1β(IL- 1β), IL-6, tumor necrosis factor-α(TNF-α) and vascular endothelial growth factor (VEGF) are involved in the pathogenesis of keen articular cartilage injury remains poorly understood. AIM To measure the levels of inflammatory factors [IL-1β, IL-6, TNF-α and VEGF] in patients with knee articular cartilage injury. METHODS Fifty-five patients with knee articular cartilage injury were selected as patient groups, who were divided into three grades [mild (n = 20), moderate (n = 19) and severe (n = 16)] according to disease severity and X-ray examinations. Meanwhile, 30 healthy individuals who underwent physical examination were selected as the control group. The levels of IL-1β, IL-6, TNF-α and VEGF were measured by ELISA and immunohistochemical staining. RESULTS Compared with the control group, patient groups displayed significantly higher levels of IL-1β, IL-6, TNF-α and VEGF, and the extent of increase was directly proportional to the severity of injury (P < 0.05). In addition, the number of cells with positive staining of IL-1β, IL-6, TNF-α and VEGF in the synovial membrane were significantly increased, along with increased disease severity (P < 0.05). After treatment, the scores of visual analogue scale and the Western Ontario and McMaster University of Orthopaedic Index in patient groups were 2.26 ± 1.13 and 15.56 ± 7.12 points, respectively, which were significantly lower than those before treatment (6.98 ± 1.32 and 49.48 ± 8.96). Correlation analysis suggested that IL-1β and TNF-α were positively correlated with VEGF. CONCLUSION IL-1β, IL-6, TNF-α and VEGF levels are increased in patients with knee articular cartilage injury, and are associated with the disease severity, indicating they might play an important role in the occurrence and development of knee articular cartilage injury. Furthermore, therapeutically targeting them might be a novel approach for the treatment of keen articular cartilage injury.

A Novel Knee Orthosis in the Treatment of Patellofemoral Pain Syndrome

Context: Patellofemoral Pain (PFPS) accounts for up to 25% of knee injuries in sports medicine clinics, with up to 91% of symptoms unresolved after conservative treatment at 5 years. The variability of response to treatment reflects its multi-factorial biomechanical etiologies. Bracing has been utilized to modify patellofemoral kinematics, generally by increasing patellofemoral contact area. The DJO Reaction orthosis is unique in its shock-absorbing elastomeric design, which is created to dissipate peak stress and enhance patellar tracking. Objective: To assess whether the DJO Reaction Brace reduces pain and improves functional outcomes in patients with chronic PFPS. Design: Cohort Series. Setting: Academic Sports Medicine Clinic. Patients: Twenty-two individuals between 18 and 40 years old with chronic patellofemoral pain have failed conservative treatment. Intervention: DJO Reaction Brace. Main Outcome Measures: Kujala Anterior Knee Pain Scale, Knee Injury and Osteoarthritis Outcome Score. Results: Seven males and 10 females with an age range of 19 - 39 years old complete the study. At an average follow-up time of 55 days, the Kujala score significantly improves by 9.8%, and KOOS Scores increase by the following statistically significant amounts: symptom 3.2%, pain 10.7%, sports and recreation 12.9%, quality of life 20.2%. Conclusion: The DJO Reaction orthosis reduces knee pain, increases function, and enhances quality of life with individuals with PFPS and is effective in the conservative care of patellofemoral pain syndrome.

Establishing minimum clinically important difference values for the Patient-Reported Outcomes Measurement Information System Physical Function, hip disability and osteoarthritis outcome score for joint reconstruction, and knee injury and osteoarthritis out

AIM To establish minimum clinically important difference(MCID) for measurements in an orthopaedic patient population with joint disorders.METHODS Adult patients aged 18 years and older seeking care for joint conditions at an orthopaedic clinic took the Patient-Reported Outcomes Measurement Information System Physical Function(PROMIS~? PF) computerized adaptive test(CAT), hip disability and osteoarthritis outcome score for joint reconstruction(HOOS JR), and the knee injury and osteoarthritis outcome score for joint reconstruction(KOOS JR) from February 2014 to April 2017. MCIDs were calculated using anchorbased and distribution-based methods. Patient reports of meaningful change in function since their first clinic encounter were used as an anchor.RESULTS There were 2226 patients who participated with a mean age of 61.16(SD = 12.84) years, 41.6% male, and 89.7% Caucasian. Mean change ranged from 7.29 to 8.41 for the PROMIS~? PF CAT, from 14.81 to 19.68 for the HOOS JR, and from 14.51 to 18.85 for the KOOS JR. ROC cut-offs ranged from 1.97-8.18 for the PF CAT, 6.33-43.36 for the HOOS JR, and 2.21-8.16 for the KOOS JR. Distribution-based methods estimated MCID values ranging from 2.45 to 21.55 for the PROMIS~? PF CAT; from 3.90 to 43.61 for the HOOS JR, and from 3.98 to 40.67 for the KOOS JR. The median MCID value in the range was similar to the mean change score for each measure and was 7.9 for the PF CAT, 18.0 for the HOOS JR, and 15.1 for the KOOS JR.CONCLUSION This is the first comprehensive study providing a wide range of MCIDs for the PROMIS? PF, HOOS JR, and KOOS JR in orthopaedic patients with joint ailments.

Evidence for a Potential “Knee-Eye-Brain Axis” Involved in Mobility and Navigation Control: Knee Injury and Obesity May Disrupt Axis Integrity

Humans depend on the coordinated activity of their lower extremities for mobility, an essential feature of Homo sapiens. In addition, they use vision to use this mobility to successfully navigate through their environment. During development, mobility appears to mature first, and then it is coordinated with navigation. Thus, the two, mobility and navigation are likely interdependent in function. Recent studies have indicated that compromising the integrity of the knee, a central element of the lower extremity motion segment, can lead to molecular alterations in both the cornea including the central cornea where light passes, as well as the interior of the eye (the vitreous humor). Not all insults to the knee lead to reproducible alterations in the eye, indicating some specificity in the response. In addition, it was recently reported that alterations to the cells in the vitreous humor occur following dietary induction of obesity in a rat model. As humans with obesity, as well as arthritis of the knee are at risk for ocular involvement and exhibit altered gait characteristics, the clinical and preclinical data raise the possibility of a “knee-eye-brain axis” to control or regulate mobility and navigation. Better delineation of such an axis could have implications for variations in control during maturation, and well as during aging when vision and mobility can be compromised, with increased risk for serious falls and failure to successfully navigate the environment.

Neuromuscular interactions around the knee in children, adults and elderly

Although injury and neuromuscular activation patterns may be common for all individuals, there are certain factors which differentiate neuromuscular activity responses between children, adults and elderly. The purpose of this study is to review recent evidence on age differences in neural activation and muscle balances around the knee when performing single joint movements. Particularly, current evidence indicates that there are some interesting similarities in the neuromuscular mechanisms by which children or the elderly differ compared with adults. Both children and elderly display a lower absolute muscle strength capacity than adults which cannot fully be explained by differences in muscle mass. Quadriceps activation failure is a common symptom ofall knee injuries, irrespective of age but it is likely that its effect is more evident in children or adults. While one might expect that antagonist co-activation would differ between age categories, it appears that this is not the case. Although hamstring: quadriceps ratio levels are altered after knee injury, it is not clear whether this is an age specific response. Finally, evidence suggests that both children and the elderly display less stiffness of the quadriceps muscle-tendon unit than adults which affects their knee joint function.

Treatment of Floating Knee Injury in Children

The necessity and superiority of the surgical operation on children with floating knee injury and the fracture union and complications were investigated. Twenty-eight children with floating knee injury were subjected to open reduction and internal fixation or external fixator. The patients were followed up for 18 months to 7 years. The curative effectiveness was scored by Karlstrom criteria. The results showed that no nonunion or deformity was found. The affected limb was 1.2 cm to 1.5 cm longer in 2 cases, 0.8 to 1.2 cm shorter in 3 cases than the contralateral. No severe dysfunction of knee joint occurred. The excellent-good rate was 92.8 % and the curative rate 71.4 respectively. So for children whose age is older than 5 years, it＇s a good way to treat the fractures of femur and tibia with open reduction and internal fixation or external fixator. The method can be advantageous for the nursing care, early function recovery, shortening of the hospital stay and avoidance of severe complications.

Perspectives on endogenous and exogenous tissue engineering following injury to tissues of the knee

The knee is a multi-component organ system comprised of several tissues which function coordinately to provide mobility. Injury to any one component compromises the integrity of the system and leads to adaptation of the other components. Over time, such events often lead to dysfunction and degeneration of the knee. Therefore, there has been considerable research emphasis to repair injured components in the knee including cartilage, menisci, and ligaments. Approaches to improving healing and repair/regeneration of knee tissues have included surgery, anti-sense gene therapy, injection of growth factors and inflammatory cytokine antagonists, transplantation of in vitro expanded chondrocytes, enhancement of endogenous cells via microfracture, injection of mesenchymal stem cells, and implantation of in vitro tissue engineered constructs. Some of these approaches have lead to temporary improvement in knee functioning, while others offer the potential to restore function and tissue integrity for longer periods of time. This article will review the status of many of these approaches, and provide a perspective on their limitations and potential to contribute to restoration of knee function across the lifespan.