Change in gliding properties of the iliotibial tract in hypermobile Ehlers-Danlos Syndrome.

PURPOSE: Fascial changes in hypermobile Ehlers-Danlos syndrome (hEDS), a heritable connective tissue disorder, can be used visualized with sonoelastography. The purpose of this study was to explore the inter-fascial gliding characteristics in hEDS. METHODS: In 9 subjects, the right iliotibial tract was examined with ultrasonography. Tissue displacements of the iliotibial tract were estimated from ultrasound data using cross-correlation techniques. RESULTS: In hEDS subjects, shear strain was 46.2%, lower than those with lower limb pain without hEDS (89.5%) and in control subjects without hEDS and without pain (121.1%). CONCLUSION: Extracellular matrix changes in hEDS may manifest as reduced inter-fascial plane gliding.

Isolated pathologies of Tensor Fasciae Latae: Retrospective cohort analysis from a tertiary referral centre.

Introduction: Tensor Fasciae Latae (TFL) and the iliotibial band (ITB) act as a single functional unit in maintaining pelvic stability whilst standing, walking, or running in human beings. The Tensor Fasciae Latae (TFL) muscle acts across the hip and the knee joint. Consequently, though its pathologies traditionally present with lateral hip pain, identifying the precise clinical diagnosis can be a challenge. Patients and methods: A retrospective search for the keyword 'Tensor Fasciae Latae'/iliotibial band (ITB) was performed of our Radiology Information System (RIS) and Picture Archiving and Communication System (PACS), Computerised Radiology Information System (CRIS) at our tertiary orthopaedic referral centre of a for orthopaedic oncology over a period of 13 years (2007-2020). Data was collected from RIS, oncology database and local histopathology laboratory records. Patient demographics, clinical characteristics, complementary imaging and clinical management outcome were documented. Results: We identified 35 patients with a mean age of 66 years (range 19-94 years). There were 18 female and 17 male patients. Lateral hip lump and pain were the most frequent clinical finding/presentation features. A variety of pathologies such as benign and malignant tumours, including vascular and tumour mimic lesions involving the TFL muscle were identified. Atrophy and pseudohypertrophy of TFL was the commonest pathology found; accounting for two thirds of the cases. Conclusion: Tensor Fasciae Latae (TFL) can be afflicted with a broad spectrum of pathologies. Radiological imaging especially cross-sectional imaging modality is crucial in guiding appropriate patient management of TFL conditions. Our analysis suggests isolated TFL lesion are more likely to be benign conditions, presenting commonly as hip pain and swelling.

Injuries to the anterolateral ligament are observed more frequently compared to lesions to the deep iliotibial tract (Kaplan fibers) in anterior cruciate ligamant deficient knees using magnetic resonance imaging.

PURPOSE: To determine the accuracy of detection, injury rate and inter- and intrarater reproducibility in visualizing lesions to the anterolateral ligament (ALL) and the deep portion of the iliotibial tract (dITT) in anterior cruciate ligament (ACL) deficient knees. METHODS: Ninety-one consecutive patients, out of those 25 children (age 14.3 ± 3.5 years), with diagnosed ACL tears were included. Two musculoskeletal radiologists retrospectively reviewed MRI data focusing on accuracy of detection and potential injuries to the ALL or dITT. Lesion were diagnosed in case of discontinued fibers in combination with intra- or peri-ligamentous edema and graded as intact, partial or complete tears. Cohen's Kappa and 95% confidence intervals (95% CI) were determined for inter- and intrarater reliability measures. RESULTS: The ALL and dITT were visible in 52 (78.8%) and 56 (84.8%) of adult-and 25 (100%) and 19 (76.0%) of pediatric patients, respectively. The ALL was injured in 45 (58.5%; partial: 36.4%, compleate: 22.1%) patients. Partial and comleate tears, where visualized in 21 (40.4%) and 16 (30.8%) adult- and seven (28.0%) and one (4%) peditric patients. A total of 16 (21.3%; partial: 13.3%, compleate: 8.0%) dITT injuries were identified. Partal and complete lesions were seen in seven (12.5%) and five (8.9%) adult- and three (15.8%) and one (5.3%) pediatric patients. Combined injuries were visualized in nine (12.7%) patients. Inter-observer (0.91-0.95) and intra-observer (0.93-0.95) reproducibility was high. CONCLUSION: In ACL injured knees, tears of the ALL are observed more frequently compared to lesions to the deep iliotibial tract. Combined injuries of both structures are rare. Clinically, the preoperative visualization of potentially injured structures of the anterolateral knee is crucial and is important for a more personalized preoperative planning and tailored anatomical reconstruction. The clinical implication of injuries to the anterolateral complex of the knee needs further investigation. LEVEL OF EVIDENCE: II.

Corrigendum: Strain Assessment of Deep Fascia of the Thigh During Leg Movement: An in situ Study.

[This corrects the article DOI: 10.3389/fbioe.2020.00750.].

Knee Flexion Angle Following Total Knee Arthroplasty Relates to a Preoperative Range of Motion of the Hip.

BACKGROUND: Many factors have been reported to affect postoperative range of knee flexion after total knee arthroplasty (TKA); however, no study has reported the impact of preoperative range of motion of the hip to the postoperative flexion angle of the knee thus far. METHODS: Of 38 consecutive patients who underwent posterior-stabilized TKA, we assessed 21 patients after excluding 17 patients who met exclusion criteria. The range of motion of the knee and the hip, age, body-mass index, serum albumin level, HbA1c, Kellgren-Lawrence grade, knee extension strength and radiological femorotibial angle as well as postoperative knee flexion angle at three months were evaluated. The preoperative data and the knee flexion angle at three months after TKA were compared using Spearman's rank correlation coefficient. RESULTS: Knee flexion angle at three months after TKA was positively correlated with preoperative flexion (ρ = 0.616, p = 0.007) and external rotation angle (ρ = 0.576, p = 0.012) of the hip as well as preoperative knee flexion angle (ρ = 0.797, p = 0.001). There were no correlations between postoperative knee flexion angle and other preoperative data. CONCLUSIONS: Patients with restricted flexion and/or external rotation of the hip may have contractures of Gluteus maximus, Gluteus medius and Tensor fasciae latae, which can cause hypertension of iliotibial tract. It may cause decreased internal rotation of the tibia when the knee is flexed, which affects postoperative knee flexion angle, thus limited flexion and/or external rotation of the hip might restrict knee flexion angle following TKA.

Presencia de cresta ósea en la epífisis proximal de la tibia: propuesta para su incorporación en la terminologia anatomica / Presence of a bony crest in the proximal epiphysis of the tibia: proposal for its incorporation in the terminologia anatomica

RESUMEN: La Terminologia Anatomica (TA) presenta las estructuras anatómicas en un lenguaje unificado para todas las estructuras del cuerpo humano. Sin embargo, hay características como algunos accidentes óseos que no se han considerado en las actualizaciones de la TA, ya sean epónimos que no se han relacionado con términos actuales o estructuras descritas clásicamente, como es el caso de una característica ósea que se observa y palpa fácilmente en la epífisis proximal de la tibia, a nivel del cóndilo lateral, uniendo el tubérculo anterolateral de la tibia con la tuberosidad de la misma. Esta característica corresponde a una elevación lineal, descrita como lugar de inserción del tracto iliotibial y del músculo tibial anterior. Basado en lo anterior, se analizaron 65 tibias de individuos Chilenos, adultos, de ambos sexos, 60 pertenecientes a la Universidad de La Frontera y 5 a la Universidad San Sebastián, considerando como criterio de inclusión la integridad del tejido compacto en la epífisis proximal. La revisión de las muestras reveló la presencia de una elevación lineal en el 100 % de los casos, uniendo la tuberosidad de la tibia con el tubérculo anterolateral (Gerdy), no observándose elevación similar desde la tuberosidad de la tibia en dirección al cóndilo medial. Esta elevación es utilizada como referencia en la palpación durante la evaluación de la rodilla. Por las evidencias presentadas, consideramos que esta elevación debe considerarse en la TA como una característica más de la tibia, en base a su disposición lineal y elevada, además de su dirección oblicua desde la tuberosidad de la tibia al tubérculo anterolateral de la misma, por lo que proponemos denominarla como cresta anterolateral de la tibia (Crista anterolateralis tibiae).

SUMMARY: Anatomical Terminology (AT) presents anatomical structures in a unified language for all structures of the human body. However, there are characteristics such as some bone accidents that have not been considered in the TA updates, whether they are eponyms that have not been related to current terms or classically described structures, as is the case of a characteristic bone that is easily observed and palpated in the proximal epiphysis of the tibia, at the level of the lateral condyle, joining the anterolateral tubercle of the tibia with the tuberosity of the tibia. This characteristic corresponds to a linear elevation, described as the insertion site of the iliotibial tract and the tibialis anterior muscle. Based on the above, 65 tibiae from Chilean individuals, adults, of both sexes, 60 belonging to the Universidad de La Frontera and 5 from the Universidad San Sebastián were analyzed, considering as an inclusion criterion the integrity of the compact tissue in the epiphysis proximal. The review of the samples revealed the presence of a linear elevation in 100 % of the cases, joining the tibial tuberosity with the anterolateral tubercle (Gerdy), not observing similar elevation from the tibial tuberosity in the direction of the medial condyle. This elevation is used as a reference for palpation during knee evaluation. Based on the evidence presented, we consider that this elevation should be considered in TA as one more characteristic of the tibia, based on its linear and elevated disposition, in addition to its oblique direction from the tibial tuberosity to the anterolateral tubercle of the tibia, for what we propose to call it the Crista anterolateralis tibiae (anterolateral crest of the tibia).

Stiffness of the iliotibial band and associated muscles in runner's knee: Assessing the effects of physiotherapy through ultrasound shear wave elastography.

OBJECTIVES: To test the hypothesis that Iliotibial Band Syndrome (ITBS) is caused by excessive iliotibial band (ITB) tension, promoted by hip abductor and external rotator weakness, and evaluate the influence of 6 weeks of physiotherapy on ITB stiffness. DESIGN: Interventional study with control group. SETTING: Clinical. PARTICIPANTS: 14 recreational runners with ITBS and 14 healthy controls of both sexes. MAIN OUTCOME MEASURES: Ultrasound shear wave elastography, hip muscle strength, visual analog scale pain, subjective lower extremity function. RESULTS: No statistical differences in ITB tension between legs as well as between patients suffering from ITBS and healthy controls were detected. Results showed significant strength deficits in hip abduction, adduction as well as external and internal rotation. Following six weeks of physiotherapy, hip muscle strength (all directions but abduction), pain and lower extremity function were significantly improved. ITB stiffness, however, was found to be increased compared to baseline measurements. CONCLUSION: Shear wave elastography data suggest that ITB tension is not increased in the affected legs of runners with ITBS compared to the healthy leg or a physical active control group, respectively. Current approaches to the conservative management of ITBS appear ineffective in lowering ITB tone.

Strain Assessment of Deep Fascia of the Thigh During Leg Movement: An in situ Study.

Fascia is a fibrous connective tissue present all over the body. At the lower limb level, the deep fascia that is overlying muscles of the outer thigh and sheathing them (fascia lata) is involved in various pathologies. However, the understanding and quantification of the mechanisms involved in these sheathing effects are still unclear. The aim of this study is to observe and quantify the strain field of the fascia lata, including the iliotibial tract (ITT), during a passive movement of the knee. Three fresh postmortem human subjects were studied. To measure hip and knee angles during knee flexion-extension, passive movements from 0° to around 120° were recorded with a motion analysis system and strain fields of the fascia were acquired using digital image correlation. Strains were computed for three areas of the fascia lata: anterior fascia, lateral fascia, and ITT. Mean principal strains showed different strain mechanisms depending on location on the fascia and knee angle. For anterior and lateral fascia, a tension mechanism was mainly observed with major strain greater than minor strain in absolute value. While for the ITT, two strain mechanisms were observed depending on knee movement: tension is observed when the knee is extended relatively to reference position of 47°, however, pure shear can be observed when the knee is flexed. In some cases, minor strain can also be higher than major strain in absolute value, suggesting high tissue compression probably due to microstructural fiber rearrangements. This in situ study is the first attempt to quantify the superficial strain field of fascia lata during passive leg movement. The study presents some limitations but provides a step in understanding strain mechanism of the fascia lata during passive knee movement.

Ultrasound of iliotibial band syndrome.

Iliotibial band syndrome or friction syndrome is an overuse disorder of the lateral knee. It is commonly reported in athletes, such as runners and cyclists, and refers to pain related to physical activity. The diagnosis is based on clinical history and physical assessment. Imaging, including ultrasound, is mainly performed in recurrent or refractory cases. The purpose of this paper is to review the etiology, diagnosis, and therapy of iliotibial band syndrome with a focus on ultrasound imaging and ultrasound-guided treatment. Ultrasound findings include soft-tissue edematous swelling or discrete fluid collection, suggestive of bursitis, between the iliotibial band and the lateral femoral epicondyle. The thickening of the iliotibial band has been inconsistently reported. Treatment varies according to the disease phase and, in the acute phase, consists of rest, physical therapy, and anti-inflammatory medications. Ultrasound-guided local steroid injections are effective in relieving symptoms.

MRI visibility of the anterolateral ligament and the deep structures of the iliotibial tract.

PURPOSE: The visualization of potentially injured anatomical structures is crucial. Lately the anterolateral ligament (ALL) and the deep structures of the iliotibial tract (ITT) have been of increased clinical interest because of their role as important lateral stabilizers of the knee. The aim of this study was to assess the visibility of the ALL and the deep structures of the ITT using MRI. Good intra- and inter-observer reproducibility was hypothesized. METHODS: Knee MRI data from patients without ligamentous lesions were retrospectively analyzed by two radiologists at two time points using axial and coronal sequences. The visibility of the different parts of the ALL (femoral, meniscal and tibial part) and of the deep ITT, namely the deep attachments of the ITT to the distal femur and capsulo-osseous layer of the ITT, were determined on a binary (yes/no) basis. RESULTS: Seventy-one cases (42 men, 29 women) were studied. Inter-observer agreement was high. Cohen's kappa was 0.97 for the tibial part of the ALL and 0.76 for the femoral part. For the deep attachments of the ITT to the distal femur Cohen's kappa was 0.94. For each of the investigated parameters absolute agreement between the observers was at least 88%. Regarding intra-observer agreement Cohen's kappa was 0.62 for the femoral part of the ALL and 0.85 for the tibial part of the ALL. For the deep attachments of the ITT to the distal femur Cohen's kappa was 0.94. For each investigated parameter absolute agreement between the two time points was at least 83%. CONCLUSIONS: The presence of the anterolateral structures of the knee can be determined with substantial inter- and intra-observer agreement using MRI examination. This is applicable for both the ALL and the deep ITT. LEVEL OF EVIDENCE: Diagnostic study - Level III.

Autologous abdominal wall reconstruction using anterolateral thigh and iliotibial tract flap after extensive tumor resection: A case series study of 50 consecutive cases.

BACKGROUND: The utility of anterolateral thigh (ALT) + iliotibial tract (ITT) flaps for the reconstruction of large abdominal wall defects has been reported, especially in cases with huge skin defects, surgical contamination, or a history of radiotherapy. However, previous reports have mainly described short-term results such as flap success rates or incidence of wound complications. The present study reviewed 50 consecutive cases of abdominal wall reconstruction using an ALT+ITT flap after extensive tumor resection and evaluated the durability of this approach (incidence of bulge or hernia) and the factors affecting the results. PATIENTS AND METHODS: A detailed retrospective review of 50 consecutive cases was conducted. Computed tomography or magnetic resonance imaging findings were reviewed to assess the incidence of abdominal bulge or hernia. Items extracted as variables from patient records were subjected to univariate and multivariate logistic regression analyses to identify their relationship with postoperative abdominal bulge or hernia. RESULTS: Forty-six cases that were followed up for more than six months were analyzed. Twenty-three patients (50.0%) developed abdominal bulge, while none (0%) developed hernia. The multivariate logistic regression analysis revealed that old age and a high body mass index were independently associated with abdominal bulge, while abdominal defect size was not. CONCLUSIONS: Abdominal wall reconstruction using an ALT+ITT flap after extensive tumor resection was considered a reasonable option with a low risk of hernia despite a marked incidence of postoperative abdominal bulge; however, the usage of additional material may be considered depending on the situation.

Tubérculo de Gerdy: una estructura olvidada en la terminología anatómica internacional / Gerdy's tubercle: a forgotten structure in the international anatomical terminology

En la enseñanza de la anatomía, el uso de los epónimos es cada vez más escaso, sin embargo su uso aún es evidente incluso en la literatura actualizada, en este caso el uso del epónimo se acompaña generalmente del término correcto según la Terminología Anatómica Internacional (TAI). El denominado "Tubérculo de Gerdy" (TG) es un epónimo ampliamente usado en la literatura y la comunidad científica para denominar un reparo óseo ubicado en el cóndilo lateral de la tibia, corresponde a un referente anatómico y clínico importante para inserción de músculos, ligamentos y procedimientos medicoquirúrgicos de la rodilla. A pesar de esta amplia denominación, y en comparación con otros epónimos, la TAI no la incluye y no relaciona algún término oficial con esta estructura anatómica. El objetivo del trabajo fue revisar libros usados en la enseñanza de la anatomía y artículos científicos actualizados para ver la presencia y descripción de esta estructura a fin de proponer un término que se ajuste a los principios básicos de la Terminología Anatómica Internacional en concordancia con la tarea del Programa Federativo Internacional de Terminología Anatómica (FIPAT), organismo de la Federación Internacional de Asociaciones de Anatomistas (IFAA). El TG se describe como una estructura ubicada entre la tuberosidad de la tibia y la cabeza de la fíbula, refiriéndose a él con sinónimos como tubérculo del músculo tibial anterior, tubérculo del músculo tensor de la fascia lata, tubérculo del tracto iliotibial y tubérculo anterolateral de la tibia. En revistas morfológicas aparece en artículos actuales relacionados al ligamento anterolateral. Según la descripción de la literatura proponemos como término anatómico para esta estructura "Tuberculum anterolateralis tibiae", cuya traducción es usada como sinónimo por otros autores, ajustándose así a los principios básicos de la TAI. Pretendemos que estos antecedentes sean discutidos por los expertos que conforman el FIPAT.

In teaching anatomy, the use of eponyms is increasingly scarce. Nonetheless, eponyms remain evident in updated literature, in this case the use of the eponym is accompanied by the correct term according to the International Anatomical terminology (TAI) Gerdy´s tubercle (GT) is an eponym widely used in the literature and scientific community to name a lateral tubercle of the tibia. It is an insertion site of muscles and ligaments and an important anatomical reference in knee surgical procedures. Despite its importance, it is not included in the International Anatomical Terminology (IAT) and an official name for this structure is lacking. The aim of this work was to review classic books used in the anatomy teaching and recent scientific papers, and further, to propose an anatomical term for the Gerdy tubercle that fit IAT basic principles, in agreement with the International Federal Program of Anatomical Terminology (IFPAT), and organism that is part of the International Federation of Anatomist Associations (IFAA). The TG is described as a structure located between the tuberosity of the tibia and the head of the fibula, referring to it with synonyms such as tubercle of the anterior tibia, tubercle of the tensor fascia lata, tubercle of iliotibial tract and anterolateral tibial tubercle. In morphological journals it appears in current articles related to the anterolateral ligament. We propose as an anatomical term for the Gerdy´s tubercle the name of "Tuberculum anterolteralis tibiae" its translation is used as a synonym by other authors and fits the basic principles of TAI. We hope that this information be considered by the experts that make up the FIPAT.

Histology and molecular pathology of iliotibial tract contracture in patients with gluteal muscle contracture.

The present study aimed to examine the pathologic changes of the iliotibial tract and discusses its relationship with gluteal muscle contracture. Samples of contractual iliotibial tracts were collected from six patients with contractures of the gluteal muscles and iliotibial tracts during their surgical treatment. Samples of normal iliotibial tracts were collected from six patients receiving surgeries for avascular necrosis of the femoral head who had no contractures of the gluteal muscles and iliotibial tracts. The tissue samples were stained using Hematoxylin and Eosin (H&E), Masson's trichrome, and Sirius Red. The mRNA and protein levels of various tissue repair genes were determined using quantitative real-time PCR and Western blotting. Both the normal and contractual iliotibial tracts consisted of type I and III collagens. The contractual iliotibial tracts had a significantly higher proportion of type III collagen in comparison with the normal iliotibial tracts. The mRNA expression levels and protein levels of tissue repair genes TGFß 1, bFGF, and matrix metalloproteinase-1 (MMP-1) in the contractual iliotibial tracts were up-regulated in comparison with that in the normal iliotibial tracts. However, the mRNA expression levels and protein levels of tissue inhibitors of metalloproteinase-1 (TIMP) in the contractual iliotibial tracts were down-regulated in comparison with that in the normal iliotibial tracts. The contractures of both the gluteal muscles and the iliotibial tracts share similar histology and molecular pathology. Our results indicate that iliotibial tract contracture is secondary to the gluteal muscle contracture and is a constant tissue repair process.

The anterolateral ligament of the knee and the lateral meniscotibial ligament - Anatomical phantom versus constant structure within the anterolateral complex.

BACKGROUND: Concerning the ongoing controversy about the existence and nature of the anterolateral ligament (ALL) of the knee joint, we reinvestigated the formation of the anterolateral part of its fibrous capsule in anatomic specimens. Furthermore, we wanted to clarify if the lateral meniscus has established a constant anchoring to the lateral tibial condyle via a lateral meniscotibial ligament (lmtl). METHODS: Forty paired embalmed lower extremities taken from 20 human body donors (15 men and five women) underwent exact macroscopic dissection. For the detailed evaluation of the lmtl, additionally 12 specially dissected joint specimens were used. In two of these specimens, the lmtl underwent further histological examination. RESULTS: In all specimens, the anterolateral part of the knee joint fibrous capsule was established by the iliotibial tract and the anterior arm of the aponeurosis of the biceps femoris muscle. According to their close connection and the fact that the anterolateral part of the fibrous capsule is exclusively assembled by these two aponeuroses, they do not leave any space for a distinct ALL connecting the lateral femoral epicondyle and the lateral tibial condyle. The constantly present lmtl was identified as a flat, rectangular bundle of collagen and also elastic fibers reinforcing the inner aspect of the fibrous capsule. Following an oblique direction, it connected the lateral face of the lateral meniscus with the superolateral margin of the lateral tibial condyle. The lmtl measured, on average, 17.1mm in longitudinal and 13mm in anteroposterior direction. CONCLUSION: Our results show that there is no evidence for the existence of an ALL in human knee joints. It is represented either by the iliotibial tract or - most likely - by the anterior arm of the short head of the biceps femoris muscle. On the other hand, the lmtl was found to be a constantly present structure.

Tensile properties of the human iliotibial tract depend on height and weight.

BACKGROUND AND AIMS: The human iliotibial tract (IT) is increasingly used in different types of musculoskeletal models. Previous findings indicate age-dependent changes of the human IT tensile properties, these lack confirmation to date. The relationship of the human IT and anthropometrical parameters, such as body height and weight has not been investigated before. MATERIALS AND METHODS: 33 fresh human IT samples (age range 4 months to 93 years) were uniaxially tested using digital imaging correlation and the latest advances in 3D-printing to standardize biomechanical soft tissues testing. RESULTS: The tensile parameters of the human IT are not age-dependent, except for the maximum strain in males. Height significantly correlated to elastic modulus, tensile strength and maximum strain of the human IT in males. Females just showed a significant correlation between maximum strain and weight, which was contrary to the findings in males. DISCUSSION AND CONCLUSION: Age-dependency of human IT tensile parameters could not be confirmed in the larger sample size investigated in this study. Due to the strong correlation with the tensile IT parameters in males, we suggest that height should be integrated when the IT is used in simulations, such as finite element analyses of the hip and knee.

Anatomic Study and Reanalysis of the Nomenclature of the Anterolateral Complex of the Knee Focusing on the Distal Iliotibial Band: Identification and Description of the Condylar Strap.

BACKGROUND: The capsulo-osseous layer (COL), short lateral ligament, mid-third lateral capsular ligament, lateral capsular ligament, and anterolateral ligament (ALL) are terms that have been used interchangeably to describe what is probably the same structure. This has resulted in confusion regarding the anatomy and function of the anterolateral complex of the knee and its relation to the distal iliotibial band (ITB). PURPOSE: To characterize the macroscopic anatomy of the anterolateral complex of the knee, in particular the femoral condylar attachment of the distal ITB. We identified a specific and consistent anatomic structure that has not been accurately described previously; it connects the deep surface of the ITB to the condylar area and is distinct from the ALL, COL, and Kaplan fibers. STUDY DESIGN: Descriptive laboratory study. METHODS: Sixteen fresh-frozen human cadaveric knees were used to study the anterolateral complex of the knee. Standardized dissections were performed that included qualitative and quantitative assessments of the anatomy through both anterior (n = 5) and posterior (n = 11) approaches. RESULTS: The femoral condylar attachment of the distal ITB was not reliably identified by anterior dissection but was in all posterior dissections. A distinct anatomic structure, hereafter termed the "condylar strap" (CS), was identified between the femur and the lateral gastrocnemius on one side and the deep surface of the ITB on the other, in all posteriorly dissected specimens. The structure had a mean thickness of 0.88 mm, and its femoral insertion was located between the distal Kaplan fibers and the epicondyle. The proximal femoral attachment of the structure had a mean width of 15.82 mm, and the width of the distal insertion of the structure on the ITB was 13.27 mm. The mean length of the structure was 26.33 mm on its distal border and 21.88 mm on its proximal border. The qualitative evaluation of behavior in internal rotation revealed that this anatomic structure became tensioned and created a tenodesis effect on the ITB. CONCLUSION: There is a consistent structure that attaches to the deep ITB and the femoral epicondylar area. The orientation of fibers suggests that it may have a role in anterolateral knee stability. CLINICAL RELEVANCE: This new anatomic description may help surgeons to optimize technical aspects of lateral extra-articular procedures in cases of anterolateral knee laxity.

The anterolateral ligament and the deep structures of the iliotibial tract: MRI visibility in the paediatric patient.

PURPOSE: To assess the visibility of both the anterolateral ligament (ALL) and the deep structures of the iliotibial tract (ITT) by means of MRI in paediatric patients. To determine reproducibility for such measurements. METHODS: Knee MRI data from patients aged <18a without lesions of the capsule or ligaments, fractures, bone edemas, foreign material or motion artifacts were analyzed by two musculoskeletal radiologists separately and twice. The visibility of the different parts of the ALL was determined (femoral, meniscal, tibial parts). Similarly, the visibility of the different parts of the deep ITT was determined: deep attachments of the ITT to the distal femur (insertion near septum, supracondylar insertion and retrograde insertion) and capsulo-osseous layer of the ITT. RESULTS: We studied 61 cases (36 female, 25 male). Age was 15 years (±2.3). Interobserver agreement was high. Cohen's Kappa was 0.864 (95%CI: 0.715-1.000) for the tibial part of the ALL and 1.0 for the femoral part of the ALL. For the deep attachments of the ITT to the distal femur Kappa was 0.828 (95%CI: 0.685-0.971). Regarding intraobserver agreement, Cohen's Kappa was 1.0 for the femoral part of the ALL and 0.955 (95%CI: 0.867-1.000) for the tibial part of the ALL. For the deep attachments of the ITT to the distal femur Cohen's Kappa was 0.896 (95%CI: 0.782-1.000). CONCLUSION: On the basis of our findings it is concluded that the presence of the anterolateral structures of the knee can be determined by MRI in a pediatric population with substantial inter- and intraobserver agreement. This is true for both the ALL and the deep structures of the ITT. LEVEL OF EVIDENCE: Diagnostic study - Level 3.

Tensor fasciae latae muscle in human embryos and foetuses with special reference to its contribution to the development of the iliotibial tract.

BACKGROUND: The human tensor fasciae latae muscle (TFL) is inserted into the iliotibial tract and plays a critical role in lateral stabilisation of the hip joint. We previously described a candidate of the initial iliotibial tract that originated from the gluteus maximus muscle and extended distally. MATERIALS AND METHODS: This study extended our observations by examining 30 human embryos and foetuses of gestational age (GA) 7-14 weeks (crown-to-rump length 24-108 mm). At GA 7 weeks, the TFL appeared as a small muscle mass floating in the subcutaneous tissue near the origins of the gluteus medius and rectus femoris muscles. RESULTS: Subsequently, the TFL obtained an iliac origin adjacent to the rectus femoris tendon, but the distal end remained a tiny fibrous mass on the vastus lateralis muscle. Until GA 10 weeks, the TFL muscle fibres were inserted into a vastus lateralis fascia that joined the quadriceps tendon distally. The next stage consisted of the TFL muscle belly "connecting" the vastus fascia and the gluteus fascia, including our previous candidate of the initial iliotibial tract. Until GA 14 weeks, the TFL was sandwiched by two laminae of the connecting fascia. CONCLUSIONS: These findings suggested that, when the vastus lateralis fascia separated from the quadriceps tendon to attach to the tibia, possibly after birth, the resulting iliotibial tract would consist of a continuous longitudinal band from the gluteus maximus fascia, via the vastus fascia, to the tibia. Although it is a small muscle, the foetal TFL plays a critical role in the development of the iliotibial tract.

The Role of an Extra-Articular Tenodesis in Revision of Anterior Cruciate Ligament Reconstruction.

Patients who present for anterior cruciate ligament (ACL) revision with a high-grade pivot shift at the time of an index ACL revision procedure and subsequent reconstruction failure or a high-grade pivot shift at revision surgery, patients with generalized joint laxity, and those requiring softs tissue grafts should be considered candidates for lateral tenodesis to supplement intraarticular graft revision. Although there is no consensus regarding the optimal lateral tenodesis technique, due to the tibial positioning associated with tensioning and fixation of extra-articular procedures, a lateral tenodesis should not be used in patients with posterolateral corner injuries or lateral compartment articular disease.

Biomechanics of the Anterolateral Structures of the Knee.

This article describes the complex anatomic structures that pass across the lateral aspect of the knee, particularly the iliotibial tract and the underlying anterolateral ligament and capsule. It provides data on their strength and roles in controlling tibiofemoral joint laxity and stability. These findings are discussed in relation to surgery to repair or reconstruct the anatomic structures, or to create tenodeses with similar effect.