Conceptos actuales en osteotomías en doble nivel alrededor de la rodilla / Current concepts in double-level osteotomies around the knee

Con la osteotomía en un solo nivel, se puede lograr la corrección del eje de la extremidad en pacientes con deformidades combinadas femoral y tibial, pero de forma simultánea generará una alteración patológica de oblicuidad de la interlínea articular, lo que conducirá a elongación ligamentaria, inestabilidad, degeneración condral y, en última instancia, comprometerá su sobrevida y los resultados funcionales. En virtud del análisis de la literatura más reciente, podemos concluir que existe un número significativo de pacientes que requieren de un procedimiento combinado para lograr un objetivo biomecánico óptimo. La finalidad de una osteotomía en doble nivel alrededor de la rodilla consiste en restablecer la anatomía normal, descargar el compartimiento afectado, normalizar los ángulos mecánicos y la orientación de la interlínea articular. Los ejes fisiológicos pueden restablecerse a través de un análisis preoperatorio exhaustivo, respetando principios biomecánicos y fijación estable con placas bloqueadas. Es un procedimiento demandante y con indicaciones en evolución, que progresivamente se ha instaurado como una alternativa de tratamiento justificada en estudios clínicos y biomecánicos para el manejo de deformidades severas alrededor de la rodilla.

With single-level osteotomy, correction of the limb axis in patients with combined femoral and tibial deformities can be achieved. This correction, however, will generate a pathological alteration in the joint line oblicuity, leading to ligament elongation, instability, joint degeneration and, ultimately, it will compromise the longevity and functional results of the correction. By analyzing the most recent literature, we can conclude that there is a significant number of patients who require a combined procedure to achieve an optimal biomechanical goal. The purpose of a double-level osteotomy around the knee is to restore normal anatomy, unload the affected compartment, normalize the mechanical angles and the orientation of the joint line. Physiological axes can be reestablished by means of a thorough preoperative analysis, observing the biomechanical principles and stable fixation with locked plates. It is a demanding procedure with increasing indications, which has progressively been established in clinical and biomechanical studies as a justified treatment alternative for the management of severe deformities around the knee.

Análisis biomecánico de la continuación prepatelar del cuádriceps / Biomechanical assessment of the prepatellar quadriceps continuation

OBJETIVO Determinar la resistencia máxima a la tracción (RMT) de la continuación prepatelar del cuádriceps (CPC).MATERIALES Y MÉTODOS Se realizó un estudio en cadáveres humanos. Fueron incluidos diez especímenes, en los cuales se utilizaron los tercios proximal y medial de la cortical anterior de la patela para evaluar las propiedades mecánicas de la CPC. En cada espécimen, se estudió un área de sección transversal de 0,2 cm2 (A1) y 1 cm2 (A2). Se aplicó una carga gradual para determinar la RMT.RESULTADOS La mediana de la RMT en el A1 fue de 232,56 N (rango: 141,23 N a 295,33 N) y en el A2 fue de 335,30 N (rango: 216,45 N a 371,40 N). El incremento en la TMR fue significativo entre las 2 áreas (p = 0,006).CONCLUSIÓN El ignificado clínico de este estudio es que la CPC es un tejido fuerte que puede servir de anclaje seguro para reconstrucciones alrededor de la patela. Un área relativamente pequeña tolera al menos 140 N y, a medida que crece el área, también aumenta la RMT.

OBJETIVE To determine the ultimate tensile strength (UTS) of the prepatellar quadriceps continuation (PQC). MATERIALS AND METHODS A human cadaveric study was performed. Ten fresh-frozen specimens were used. The proximal and medial thirds of the anterior cortex of the patella were used to assess the mechanical properties of the PQC. In each specimen, transverse section areas measuring 0.2 cm2 (A1) and 1 cm2 (A2) were studied. A gradual load was applied to determine the UTS. RESULTS The median UTS of A1 was of 232.56 N (range: 141.23 N to 295.33 N), and that of A2 was of 335.30 N (range: 216.45 N to 371.40 N). The increment in UTS was significant between the 2 areas (p » 0.006). CONCLUSION The clinical significance of the present study lies in the fact that it shows that the PQC is a strong tissue that can be a safe anchor for reconstruction around the patella. A relatively small area supports at least 140 N, and, as the area grows, the UTS increases as well.

Fiabilidad y validez concurrente de la app Goniometer Pro vs goniómetro universal en la determinación de la flexión pasiva de rodilla / Reliability and concurrent validity of the app Goniometer Pro vs Universal Goniometer in the determination of passive knee flexion

Resumen: Antecedentes: Los teléfonos inteligentes se han convertido en una parte fundamental de nuestra sociedad, no sólo cotidiana, sino también profesional, pues han surgido numerosas aplicaciones para el ámbito sanitario. El objetivo del estudio fue analizar la fiabilidad y validez concurrente de una app para iPhone en relación con la goniometría tradicional. Material y métodos: Estudio comparativo y descriptivo de validación no experimental a doble ciego. En una muestra de 21 sujetos se realizaron cuatro mediciones de movilidad de rodilla: dos mediante goniometría universal (GU) y dos mediante la aplicación Goniometer-Pro (G-Pro) para iPhone. La radiografía se empleó como medida de referencia del ángulo de flexión de rodilla y fue analizada por un único evaluador que comparó este resultado con el de los otros evaluadores. Resultados: La diferencia entre los valores medios intragrupos fue de 3.148o (± 2.669o) para GU y 2.476o (± 2.638o) para G-Pro. La diferencia de medias intergrupos alcanzó 5.45o. La fiabilidad interobservador fue de 0.990 para GU y 0.993 para G-Pro; en cuanto a la validez, los valores obtenidos fueron 0.976 para GU y 0.992 para G-Pro. Conclusiones: La app G-Pro es una herramienta fiable y con una elevada exactitud para medir el ángulo de flexión de la rodilla. Sus resultados son ligeramente superiores y más precisos a los de la goniometría tradicional.

Abstract: Background: Smartphones have become a fundamental part of our society, not only everyday, but also professional, since many applications have emerged for the health field. The objective of the study was to analyze the reliability and concurrent validity of an app for iPhone in relation to traditional measurement. Material and methods: A non-experimental, double-blind validation and descriptive study. On a sample of 21 subjects, four measurements of knee mobility were performed. Two using universal goniometer (GU) and two through the application Goniometer-Pro (G-Pro) for IPhone. The X-ray was used as a reference measure of the knee flexion angle and was analyzed by a single evaluator who compared this result with that of the other evaluators. Results: The difference between the average intra-group values was 3.148o (± 2.669o) for GU and 2.476o (± 2.638o) for G-Pro. The inter-group mean difference reached 5.45o. The Inter-observer reliability was 0.990 for GU and 0.993 for G-Pro; as for validity, the values obtained were 0.976 for GU and 0.992 for G-Pro. Conclusions: The G-Pro app is a reliable tool with a high accuracy to measure the knee flexion angle. Its results are slightly superior and more accurate to those of traditional instruments.

Principios biomecánicos en inestabilidad crónica posterolateral de rodilla / Biomechanical principles of chronic posterolateral knee instability

La inestabilidad crónica posterolateral de rodilla continúa siendo un tema desafiante desde la evaluación clínica hasta la resolución definitiva. La comprensión de la anatomía, biomecánica articular y las adaptaciones evolutivas de la rodilla para su complejo funcionamiento, son esenciales para el razonamiento diagnóstico y terapéutico de esas lesiones.

Chronic posterolateral knee instability continues to be a challenging issue from clinical evaluation to final resolution. The understanding of anatomy, joint biomechanics and evolutionary adaptations of the knee for its complex functioning are essential for the diagnostic and therapeutic reasoning of these injuries.

Effects of Motor Learning on Clinical Isokinetic Test Performance in Knee Osteoarthritis Patients

OBJECTIVES: To analyze the effects of motor learning on knee extension-flexion isokinetic performance in knee osteoarthritis patients. METHODS: One hundred and thirty-six middle-aged and older sedentary individuals (111 women, 64.3±9.9 years) with knee osteoarthritis (130 patients with bilateral) and who had never performed isokinetic testing underwent two bilateral knee extension-flexion (concentric-concentric) isokinetic evaluations (5 repetitions) at 60°/sec. The tests were first performed on the dominant leg with 2 min of recovery between test, and following a standardized warm-up that included 3 submaximal isokinetic repetitions. The same procedure was repeated on the non-dominant leg. The peak torque, peak torque adjusted for the body weight, total work, coefficient of variation and agonist/antagonist ratio were compared between tests. RESULTS: Patients showed significant improvements in test 2 compared to test 1, including higher levels of peak torque, peak torque adjusted for body weight and total work, as well as lower coefficients of variation. The agonist/antagonist relationship did not significantly change between tests. No significant differences were found between the right and left legs for all variables. CONCLUSION: The results suggest that performing two tests with a short recovery (2 min) between them could be used to reduce motor learning effects on clinical isokinetic testing of the knee joint in knee osteoarthritis patients.

Osteoarthritis model induced by intra-articular monosodium iodoacetate in rats knee

ABSTRACT PURPOSE: To evaluate the usefulness of a knee osteoarthritis model through functional, radiological and microscopic changes of the synovial membrane. METHODS: Forty eight rats were divided randomly into two groups. The first received 0.9% saline in the joint and corresponded to the control group. The second was submitted to experimental osteoarthritis of the right knee induced by monosodium iodoacetate and corresponded to the osteoarthritis group. All animals were subjected to comparative tests of forced ambulation and joint movements, inability to articulate and tactile allodynia on day 1 post-experiment by forced ambulation (Roto-rod test), joint assessment of disability (weight bearing test) and assessment of tactile allodynia (Von Frey test). After inflammatory induction they were divided into four sub-groups corresponding to the scheduled death in 7, 14, 21 and 28 days when they were submitted to radiographic examination of the knee, arthrotomy and collection of the synovial membrane. RESULTS: The osteoarthritis group showed significant differences compared to control group on days 7 and 14 in Roto-rod, in weight bearing and Von Frey tests in all days, and in radiological evaluation. Microscopic examination of the synovial membrane showed abnormalities of inflammatory character at all stages. CONCLUSION: The osteoarthritis induced by intra-articular monosodium iodoacetate in rats knee is a good model to be used in related research, because it provides mensurable changes on joint movements, tactile allodynia, progressive radiological degeneration and microscopic inflammation of the synovial membrane, that represent markers for osteoarthritis evaluation

Evaluation of static and dynamic balance in athletes with anterior cruciate ligament injury – A controlled study

OBJECTIVES: Anterior cruciate ligament injury leads to adaptive responses to maintain postural control. However, there is no consensus regarding whether leg dominance also affects postural control in athletes with anterior cruciate ligament injury. The purpose of this study was to evaluate dynamic and static postural control among athletes with and without anterior cruciate ligament injury to the dominant leg. METHODS: Twenty-eight athletes, twenty-one males and seven females aged 15-45 years, were allocated to one of two groups: the anterior cruciate ligament injury group (26±3 years) or the control group without anterior cruciate ligament injury (25±6.5 years). All subjects performed one legged stance tests under eyes open and eyes closed conditions and squat and kick movement tests using a postural control protocol (AccuSwayPlus force platform, Massachusetts). The center of pressure displacement and speed were measured by the force platform. In addition, the distance traveled on the single-leg hop test was assessed as an objective measure of function. RESULTS: Significantly greater mediolateral sway was found under the eyes closed condition (p=0.04) and during squat movement (p=0.01) in the anterior cruciate ligament injury group than in the control group. Analysis of the single-leg hop test results showed no difference between the groups (p=0.73). CONCLUSION: Athletes with anterior cruciate ligament injury had greater mediolateral displacement of the center of pressure toward the dominant leg under the eyes closed condition and during squat movement compared to control athletes.

Análise do déficit bilateral de torque entre gêneros na extensão e flexão do joelho / Analysis of bilateral deficit of torque between genders in extension and flexion of knee

Diariamente nós executamos tarefas bilaterais e unilaterais que dependem do controle da força muscular. diversos estudos observaram que há uma diferença entre a força total exercida bilateralmente e a soma das forças unilaterais, conhecido como déficit bilateral (db), porém suas causas e mecanismos ainda são divergentes. entender este processo pode nos ajudar a melhorar o desempenho físico, o treinamento e a força muscular. desta forma, o objetivo deste estudo foi avaliar diferença entre homens (n=18, idade: 29,1 ± 5,0 anos, estatura: 175,1 ± 6,1 cm, peso: 81,3 ± 11,1 kg) e mulheres na fase folicular do ciclo menstrual (n=18, idade: 29,9 ± 4,9 anos, estatura: 162,8 ± 5,6 cm, peso: 69,2 ± 13,0 kg) jovens e saudáveis sobre o db. uma análise biomecânica foi realizada, obtida através do pico de torque e do ângulo no momento do pico do torque (apt) nas análises unilaterais e bilaterais. foi utilizado um dinamômetro isocinético modificado para análise bilateral e a intensidade da atividade muscular foi mensurada através da eletromiografia (emg). os resultados obtidos comprovam a existência do db para ambos gêneros nos extensores (h = -19,36; m = -21,40) e flexores (h = -23,47; m = -28,80). não foram observadas diferenças em relação ao gênero (p = 0,188). foram encontradas diferenças significativas nos índices do db entre gêneros nos extensores (p = 0,012) mas não nos flexores (p = 0,389). não foram observadas diferenças entre o sentido de movimento para homens (p = 0,241) e mulheres (p = 0,0543). quanto à atividade muscular na extensão de joelhos, homens apresentaram maior ativação muscular do que mulheres em todas as condições unilaterais (p < 0,05). não foram observadas diferenças significativas no sinal emg para homens e mulheres (p > 0,05) exceto nos extensores (p = 0,003). os resultados para a razão flexão/extensão apresentaram valores entre 0,67 e 0,73 para homens e 0,64 a 0,69 para mulheres. os valores médios dos apt's variaram entre a extensão (h: aptd = 62,1; apte = 59,5; aptb = 52,5 / m: aptd =. 64,3; apte = 60,1; aptb = 55,9) e a flexão (h: aptd = 31,8; apte = 30,6; aptb = 34,8 / m: aptd = 36,8; apte = 36,0; aptb = 42,2) (p < 0,01). podemos concluir que, neste estudo, foi observado o déficit bilateral, não havendo diferenças entre gêneros sobre o db e ativação muscular assim como fatores biomecânicos podem exercer influência sobre o índice do db

Daily we perform bilateral and unilateral tasks that depends on muscular strength control. Several studies observed that there is a difference between total force played bilaterally and the sum of unilateral forces, known as bilateral deficit (BD), however its causes and mechanisms still are divergent. Understand this process can help us to improve physical performance, training and muscular strength. Thus, the aim of this study was to assess the difference between young and healthy men (n=18, age: 29.1 ± 5.0 years, height: 175.1 ± 6.1 cm, weight: 81.3 ± 11.1 kg) and women in follicular phase of menstrual cycle (n=18, age: 29.9 ± 4.9 years, height: 162.8 ± 5.6 cm, weight: 69.2 ± 13.0 kg) on BD. A biomechanical analysis was accomplished, obtained through the angle at the moment of peak torque (PTA) in the unilateral and bilateral analysis. A modified isokinetic dynamometer for bilateral analysis was used and intensity of the muscular activity was obtained through the electromyography (EMG). The results obtained showed BD for both genders in extensors (H = -19.36; M = -21.40) and flexors (H = -23.47; M = -28.80). Significant differences in the indices of BD between genders where found in extensors (p = 0.012) but in flexors (p = 0.389). Differences between the direction of movement for men (p = 0.241) and women (p = 0.0543) were not observed. On muscular activity in extension of knees, men showed greater muscular activation than women (p < 0.05). Significant differences were found in EMG for men and women (p > 0.05) except in the extensors in men (p = 0.003). The results for the ratio Flexion/Extension had presented values between 0.67 and 0.73 for men and 0.64 to 0.69 for women. The average values of the PTA's showed in extension (M: PTAR = 62.1°; PTAL = 59.5°; PTAB = 52.5° / W: PTAR = 64.3°; PTAL = 60.1°; PTAB = 55.9°) differed when compared to flexion (M: PTAR = 31.8°; PTAL = 30.6°; PTAB = 34.8° / M: PTADR = 36.8°; PTAEL = 36.0°; PTAB = 42.2°) (p < 0.01). We can conclude that, in this study, the bilateral deficit was observed, not having differences between genders on BD and muscular activation and that the CC as well as biomechanical factors can exert influence on the index of the BD

Genu Recurvatum versus Fixed Flexion after Total Knee Arthroplasty

BACKGROUND: To date, there is no study comparing outcomes between post-total knee replacement genu recurvatum and fixed flexion. This study aims to provide data that will help in deciding which side to err on when neutral extension is not achieved. METHODS: A prospective cohort study of primary total knee arthroplasties was performed, which compared the 6-month and 2-year clinical outcomes between fixed flexion and genu recurvatum deformities at 6 months. RESULTS: At 6 months, knees in genu recurvatum did better than knees in fixed flexion deformity in terms of knee flexion. However, at 2 years, knees in fixed flexion deformity did better in terms of knee scores and showed better improvement in the degree of deformity. CONCLUSIONS: We conclude that it is better to err on the side of fixed flexion deformity if neutral alignment cannot be achieved.

Brucella melitensis es un agente de la artritis pediatrica: Serie de casos / Brucella melitensis is an agent in pediatric arthritis: Case series

La brucelosis es un importante problema de salud y, en algunas regiones, es endémica. En ella, es muy frecuente observar un compromiso osteoarticular (20%-60%). En regiones donde es endémica, al analizar la etiología de la artritis, hay que pensar en esta entidad. En este artículo, se informan los casos de 12 pacientes; 11 de ellos eran varones, y la media de edad fue de 12 años (intervalo: de 2 a 17 años). Se determinó el compromiso de la cadera en 9 pacientes; de la articulación sacroilíaca, en 2; y de la rodilla, en 1. Todos los pacientes tenían artralgia; 8 pacientes tuvieron fiebre; y 1 paciente, leucocitosis. A un paciente se lo sometió a un tratamiento quirúrgico debido a artritis séptica. La infección puede derivar en complicaciones graves, especialmente en el compromiso del aparato locomotor. Debe tenerse en cuenta que, mediante el diagnóstico y tratamiento tempranos, es posible prevenir las complicaciones.

Brucellosis is a significant health problem and is endemic in some regions. Osteoarticular involvement is seen most frequently in brucellosis (20-60%). In regions where brucellosis is endemic, it should be considered in the etiology of arthritis. We report the 12 cases, were 11 males with a mean age of 12 years (range, 2-17 years). Involvement was determined in the hip in 9 cases, the sacroiliac joint in 2 and the knee in 1. All the cases had arthralgia, fever was determined in 8 cases and leukocytosis in one case. Surgical treatment was applied to one case because of septic arthritis. Serious complications of the infection may be encountered and particularly in musculoskeletal system involvement, it should be kept in mind that complications can be prevented by early diagnosis and treatment

Male and female runners demonstrate different sagittal plane mechanics as a function of static hamstring flexibility

ABSTRACTBackground:Injuries to runners are common. However, there are many potential contributing factors to injury. While lack of flexibility alone is commonly related to injury, there are clear differences in hamstring flexibility between males and females.Objective: To compare the effect of static hamstring length on sagittal plane mechanics between male and female runners.Method: Forty subjects (30.0±6.4 years) participated and were placed in one of 4 groups: flexible males (n=10), inflexible males (n=10), flexible females (n=10), and inflexible females (n=10). All subjects were free of injury at the time of data collection. Three-dimensional kinematics and kinetics were collected while subjects ran over ground across 2 force platforms. Sagittal plane joint angles and moments were calculated at the knee and hip and compared with a 2-way (sex X flexibility) ANOVA (α=0.05).Results: Males exhibited greater peak knee extension moment than females (M=2.80±0.47, F=2.48±0.52 Nm/kg*m, p=0.05) and inflexible runners exhibited greater peak knee extension moment than flexible runners (In=2.83±0.56, Fl=2.44±0.51 Nm/kg*m, p=0.01). For hip flexion at initial contact, a significant interaction existed (p<0.05). Flexible females (36.7±7.4º) exhibited more hip flexion than inflexible females (27.9±4.6º, p<0.01) and flexible males (30.1±9.5º, p<0.05). No differences existed for knee angle at initial contact, peak knee angle, peak hip angle, or peak hip moment.Conclusion: Hamstring flexibility results in different mechanical profiles in males and females. Flexibility in the hamstrings may result in decreased moments via active or passive tension. These differences may have implications for performance and injury in flexible female runners.

Efficacy of Direct Injection of Etanercept into Knee Joints for Pain in Moderate and Severe Knee Osteoarthritis

PURPOSE: Osteoarthritic (OA) pain is largely considered to be inflammatory pain. However, during the last stage of knee OA, sensory nerve fibers in the knee are shown to be significantly damaged when the subchondral bone junction is destroyed, and this can induce neuropathic pain. Several authors have reported that tumor necrosis factor-alpha (TNFalpha) in a knee joint plays a crucial role in pain modulation. The purpose of the current study was to evaluate the efficacy of etanercept, a TNFalpha inhibitor, for pain in knee OA. MATERIALS AND METHODS: Thirty-nine patients with knee OA and a 2-4 Kellgren-Lawrence grading were evaluated in this prospective study. Patients were divided into two groups; hyaluronic acid (HA) and etanercept injection. All patients received a single injection into the knee. Pain scores were evaluated before and 4 weeks after injection using a visual analogue scale (VAS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and they were compared between the groups. RESULTS: Before injection, VAS and WOMAC scores were not significantly different between the groups (p>0.05). Significant pain relief was found in the etanercept group at 1 and 2 weeks by VAS, and at 4 weeks by WOMAC score, compared with the HA group (p<0.05). No adverse events were observed in either group. CONCLUSION: Direct injection of etanercept into OA knee joints was an effective treatment for pain in moderate and severe OA patients. Furthermore, this finding suggests that TNFalpha is one factor that induces OA pain.

Effect of Rhythmic Auditory Stimulation on Hemiplegic Gait Patterns

PURPOSE: The purpose of our study was to investigate the effect of gait training with rhythmic auditory stimulation (RAS) on both kinematic and temporospatial gait patterns in patients with hemiplegia. MATERIALS AND METHODS: Eighteen hemiplegic patients diagnosed with either cerebral palsy or stroke participated in this study. All participants underwent the 4-week gait training with RAS. The treatment was performed for 30 minutes per each session, three sessions per week. RAS was provided with rhythmic beats using a chord progression on a keyboard. Kinematic and temporospatial data were collected and analyzed using a three-dimensional motion analysis system. RESULTS: Gait training with RAS significantly improved both proximal and distal joint kinematic patterns in hip adduction, knee flexion, and ankle plantar flexion, enhancing the gait deviation index (GDI) as well as ameliorating temporal asymmetry of the stance and swing phases in patients with hemiplegia. Stroke patients with previous walking experience demonstrated significant kinematic improvement in knee flexion in mid-swing and ankle dorsiflexion in terminal stance. Among stroke patients, subacute patients showed a significantly increased GDI score compared with chronic patients. In addition, household ambulators showed a significant effect on reducing anterior tilt of the pelvis with an enhanced GDI score, while community ambulators significantly increased knee flexion in mid-swing phase and ankle dorsiflexion in terminal stance phase. CONCLUSION: Gait training with RAS has beneficial effects on both kinematic and temporospatial patterns in patients with hemiplegia, providing not only clinical implications of locomotor rehabilitation with goal-oriented external feedback using RAS but also differential effects according to ambulatory function.

Rhupus syndrome

No abstract available.

Utilization of Hyaluronate and Incidence of Septic Knee Arthritis in Adults: Results from the Korean National Claim Registry

BACKGROUND: Septic arthritis of the knee has been reported recently in adult patients who were administered hyaluronate. We evaluated the incidence of septic knees and the utilization of hyaluronate in the Korean adult population using nationwide data from the Health Insurance Review and Assessment Service (HIRA). METHODS: All new admissions to the clinics or hospitals for septic knees were recorded in the HIRA database which was established by the Korean government and covers the Korean population using the International Classification of Diseases-10 revision code. We evaluated the incidence of septic arthritis of the knees in the population above 50 years of age. Hyaluronate prescription data was also collected from the HIRA database. RESULTS: In 2012, the incidence of septic knees was 2.7 per 100,000 persons in men and 4.2 per 100,000 persons in women, respectively. The age-adjusted incidence of septic knees increased by 6.7% per year (95% confidence interval, 3.3 to 10.1), and the annual number of prescriptions of hyaluronate increased about 1.5-fold during the study period. CONCLUSIONS: Cautious aseptic technique is required when hyaluronate is administered in adult patients with osteoarthritis of the knee due to the concerns of the risk of septic arthritis.

Application of isokinetic muscle testing in identification of the faked paralysis / 法医学杂志

OBJECTIVE@#To study the application of isokinetic muscle testing in identification of the faked paralysis to provide scientific data for establishing a standard system of muscle strength in forensic medicine identification.@*METHODS@#Fifty-seven patients with bone fracture or nerve damage as damaged group and 128 normal subjects pretended paralysis as faked paralyzed group were included in this study. Isokinetic muscle testing was performed on bilateral knees of all subjects in the two groups. The peak torque (PT) and peak torque angle (PTA) were compared between both sides in each group. The features of torque-time graph of two groups were classified.@*RESULTS@#In the damaged group, the differences of PT between two sides of flexors and extensors were statistically significant (P<0.05), while the dif- ferences of PTA were not statistically significant (P>0.05). In faked paralyzed group, the differences of PT and PTA between two sides of flexors and extensors were both statistically significant (P<0.05). The torque-time graph of damaged knee presented mostly as single lead peak, while torque-time graph of the faked paralyzed knee presented mostly as multiple peaks.@*CONCLUSION@#The feature of torque-time graph could be useful to identify the faked paralyzed extremities in forensic authentication.

Patellofemoral Crepitus after Total Knee Arthroplasty: Etiology and Preventive Measures

Patellofemoral crepitus and clunk syndrome are infrequent, yet troublesome complications of total knee arthroplasty with a reported incidence of 0%-18%. They are primarily associated with implantation of posterior cruciate substituting designs. These entities are the result of peripatellar fibrosynovial hyperplasia at the junction of the superior pole of the patella and the distal quadriceps tendon which becomes entrapped within the superior aspect of the intercondylar box of the femoral component during knee flexion. When the knee extends, a crepitant sensation occurs as the fibrosynovial tissue exits the intercondylar box. Numerous etiologies have been proposed such as femoral component designs with a high intercondylar box ratio, previous knee surgery, reduced patellar tendon length, thinner patellar components, reduced patella-patellar component composite thickness, and smaller femoral components. Preventative measures include choice of femoral components with a reduced intercondylar box ratio, use of thicker patellar components, avoidance of over-resection of the patella, and debridement of the fibrosynovial tissue at the time of knee arthroplasty. Most patients with crepitus are unaware of the problem or have minimal symptoms so that no treatment is required. If significant disability is incurred, symptoms can be eliminated in a high percentage of patients with arthroscopic debridement of the fibrosynovial hyperplasia.

The Relationship between Osteoarthritis of the Knee and Bone Mineral Density of Proximal Femur: A Cross-Sectional Study from a Korean Population in Women

BACKGROUND: The relationship between osteoarthritis (OA) and osteoporosis (OP) is complicated and it may differ according to the site or stage of disease. The purpose of this cross-sectional study is to examine the relationship between the severity of radiological knee OA and the degree of OP in the ipsilateral proximal femur as denoted by bone mineral density (BMD) in a Korean population, especially among women. METHODS: One hundred ninety-five female patients who had knee pain and radiological knee OA were investigated with respect to the relationship of knee OA severity with BMD. The BMD of the proximal femur and spine was measured by dual energy X-ray absorptiometry, and the severity of knee OA was evaluated based on Kellgren-Lawrence (K-L) radiographic criteria, joint space narrowing (JSN) and mechanical axis of knee alignment. Partial correlation analysis and ANCOVA adjusted for confounding factors (age and body mass index) were performed to assess the relationship. RESULTS: There was a statistically significant relationship between the BMD of the proximal femur and JSN, and the BMD of the proximal femur was positively associated with increased joint space width. There was a lack of association between the spine BMD and JSN. The BMD of the proximal femur was also significantly lower in patients who had a higher K-L grade. CONCLUSIONS: The radiographic finding of severe OA in the knee is associated with decreased BMD of the ipsilateral proximal femur including the femoral neck, trochanter, intertrochanter, and region of the entire hip (neck, trochanter, and Ward's triangle).

Anterior Knee Pain in Patients with Cerebral Palsy

BACKGROUND: The aim of this study was to identify the risk factors for anterior knee pain in patients with cerebral palsy. METHODS: This prospective study investigated the risk factors for anterior knee pain in 127 ambulatory patients with spastic cerebral palsy in terms of walking pain, resting pain, and provocative pain. Demographic data analysis and physical examination for measuring the knee flexion contracture and unilateral and bilateral popliteal angles were performed. Patellar height was measured on radiographs, and patella alta was identified. The risk factors for anterior knee pain were analyzed using multivariate analysis with a generalized estimating equation. RESULTS: Seventy-seven patients were found to have patella alta based on the radiographic measurements (60.6%). Overall, sixteen patients (12.6%) had either unilateral or bilateral anterior knee pain. Of these, 6 patients showed a visual analogue scale (VAS) 7. Age was found to be a significant risk factor for walking pain and resting pain with odds ratios (ORs) of 1.08 (95% confidence interval [CI], 1.02 to 1.14) and 1.09 (95% CI, 1.03 to 1.15), respectively. In the multivariate analysis, knee flexion contracture was a significant protective factor with an OR of 0.92 (95% CI, 0.85 to 0.98). CONCLUSIONS: Approximately 12.6% of ambulatory patients with spastic cerebral palsy were found to have anterior knee pain in our hospital-based cohort study. Age was found to be a significant risk factor for anterior knee pain while walking and resting.

Biomechanics of Hyperflexion and Kneeling before and after Total Knee Arthroplasty

The capacity to perform certain activities is frequently compromised after total knee arthroplasty (TKA) due to a functional decline resulting from decreased range of motion and a diminished ability to kneel. In this manuscript, the current biomechanical understanding of hyperflexion and kneeling before and after TKA will be discussed. Patellofemoral and tibiofemoral joint contact area, contact pressure, and kinematics were evaluated in cadaveric studies using a Tekscan pressure measuring system and Microscribe. Testing was performed on intact knees and following cruciate retaining and posterior stabilized TKA at knee flexion angles of 90degrees, 105degrees, 120degrees, and 135degrees. Three loading conditions were used to simulate squatting, double stance kneeling, and single stance kneeling. Following TKA with double stance kneeling, patellofemoral contact areas did not increase significantly at high knee flexion angle (135degrees). Kneeling resulted in tibial posterior translation and external rotation at all flexion angles. Moving from double to single stance kneeling tended to increase pressures in the cruciate retaining group, but decreased pressures in the posterior stabilized group. The cruciate retaining group had significantly larger contact areas than the posterior stabilized group, although no significant differences in pressures were observed comparing the two TKA designs (p < 0.05). If greater than 120degrees of postoperative knee range of motion can be achieved following TKA, then kneeling may be performed with less risk in the patellofemoral joint than was previously believed to be the case. However, kneeling may increase the likelihood of damage to cartilage and menisci in intact knees and after TKA increases in tibiofemoral contact area and pressures may lead to polyethyelene wear if performed on a chronic, repetitive basis.