No study has investigated the three-dimensional morphological changes of the anterior cruciate ligament (ACL) during functional activities in vivo. The purpose of this study was to analyze the elongation, rotation (twist), and orientation of the ACL during weight-bearing flexion in five human subjects using dual-orthogonal fluoroscopic images and MR image-based ...

The purpose of this study was to evaluate the effect of the knee position at three different flexion angles in magnetic resonance (MR) delineation of the anterior cruciate ligament (ACL) in the knee and to determine the optimal knee position. Thirteen knees of normal volunteers were examined at 15 degrees, ...

OBJECTIVE: To estimate the prevalence of bone and soft tissue abnormalities in asymptomatic knees using peripheral magnetic resonance imaging (pMRI) and to examine the relationship between these abnormalities and Kellgren-Lawrence (K-L) graded X-rays. METHOD: Volunteers (20-68 years) with no history of knee pain, injury or bone or joint disease were ...

Clinical management of knee ligament injuries ranges from simple observation to complex multiligament reconstruction. Radiographic evaluation, including magnetic resonance imaging, is an important part of the diagnostic regimen that may significantly alter the treatment plan. This article reviews the clinical presentation and evaluation of isolated and combined knee ligament injuries ...

OBJECTIVE: This study was designed to assess the MR appearance of the medial perimalleolar fat in an asymptomatic population and describe the MRI appearance of the medial malleolar bursa. CONCLUSION: The MRI findings of medial perimalleolar fat in asymptomatic individuals and in patients with suspected medial malleolar bursa include normal ...

BACKGROUND: Recent studies have questioned the utility of magnetic resonance imaging in the diagnosis of pediatric knee disorders because of the morphologic changes during growth and the low accuracy of the formal interpretation of the magnetic resonance imaging scan by a radiologist. The purpose of this study was twofold: (1) ...

BACKGROUND: Magnetic resonance imaging (MRI) has become an important modality in the assessment of traumatic soft-tissue injury of the knee. METHODS: This prospective study was performed to evaluate the accuracy of MRI used at Wellington Hospital--by comparing the result of the scans of 67 patients with subsequent arthroscopy. RESULTS: The ...

PURPOSE: To improve the quality of magnetic resonance imaging (MRI) on knees after total knee arthroplasty (TKA) by minimizing image artifacts caused by metallic implants, and to establish a method determining in vivo kinematics of TKA knees using MRI. MATERIALS AND METHODS: Two knee implants made of cobalt-chrome and oxidized ...

The objective of the current study was to use fluoroscopy to accurately determine the three-dimensional (3D), in vivo, weight-bearing kinematics of 10 normal and five anterior cruciate ligament deficient (ACLD) knees. Patient-specific bone models were derived from computed tomography (CT) data. 3D computer bone models of each subject's femur, tibia, ...

PURPOSE: To assess the predictive value of a short magnetic resonance (MR) imaging examination, in addition to or instead of radiography, performed in patients with acute knee trauma to identify those who require additional treatment versus those who do not and can be discharged without further follow-up. MATERIALS AND METHODS: ...

Progressive degeneration of the anterior cruciate ligament (ACL) deficient knee may be partly due to chondral trauma at the time of ACL rupture and repeat episodes of subluxation, but also due to aberrant kinematics altering the wear pattern at the tibiofemoral interface. The hypothesis that altered kinematics, represented by the ...

Intra-articular lipoma is a rare benign mass that commonly occurs in the knee joint. We present the case of a 15-year-old girl with a slowly growing mass in her right knee. There was no history of trauma. The patient had no catching, locking, or giving way of the knee. On ...

The meniscal release (MR) is used to minimize meniscal pathology after Tibial Plateau Leveling Osteotomy (TPLO) surgery. The purposes of this study were: (i) to describe meniscal orientation in a unaltered cadaveric canine stifle, a cruciate deficient stifle, TPLO repaired stifle with and without the MR using magnetic resonance imaging; ...

We tried to demonstrate an association between magnetic resonance imaging findings of the Hoffa fat pad and patellar chondropathy. Parallely, we checked the correlation between the diagnosis of patellar chondropathy on magnetic resonance imaging and during arthroscopy. Our study is a retrospective review of the records of 135 patients who ...

Pigmented villonodular synovitis (PVNS) is a distinct but rare clinical entity often presents late with a diagnostic difficulty. Its non-specific manifestations require exclusion of several chronic inflammatory disorders and other humorous lesions but all investigations including highly predictive magnetic resonance imaging (MRI) and arthroscopic examination are non-diagnostic demanding confirmatory tissue ...

BACKGROUND: Alteration of the kinematics of the PCL-deficient knee might be a factor in producing the articular damage. Very little is known about the in vivo weightbearing kinematics of the PCL-deficient knee. HYPOTHESIS: Isolated rupture of the posterior cruciate ligament alters knee kinematics, predisposing the patient to development of early ...

BACKGROUND: Establishing the validity of classification schemes is a crucial preparatory step that should precede multicenter studies. There are no studies investigating the reproducibility of arthroscopic classification of meniscal pathology among multiple surgeons at different institutions. HYPOTHESIS: Arthroscopic classification of meniscal pathology is reliable and reproducible and suitable for multicenter ...

The increased number of patients undergoing arthroscopy or surgery of the knee for sports medicine injuries is leading to increased numbers of patients who require imaging after surgery because of failure to improve, recurrent symptoms, or new injury. As in preoperative patients, magnetic resonance (MR) imaging is the most valuable ...

PURPOSE: To demonstrate the utility of microscopic images with field-of-view of 50 mm in delineation of the medial aspect of the knee, including fascial plane, superficial and deep layers of the medial collateral ligament (MCL), and the medial meniscus. MATERIAL AND METHODS: Using a phantom, the signal-to-noise ratio (SNR) of ...

OBJECTIVE: The usefulness of coronal images in addition to sagittal images for detection of additional meniscal injuries or bone lesions has been questioned. Some authors believe meniscal tears are rarely seen only in the coronal plane. We performed a retrospective review of coronal and sagittal MR images of the knee ...

INTRODUCTION: MR imaging has emerged as an important modality in the non-invasive evaluation of osseous and soft-tissue structures in the post-traumatic knee. However, it is sometimes impossible to determine with confidence if a focus of high signal intensity in the meniscus is confined to the substance of the meniscus or ...

OBJECTIVE: To determine the patterns of patellar motion in subjects without knee symptoms using dynamic magnetic resonance imaging (MRI). DESIGN: Patellar tracking MR examinations were performed on 50 asymptomatic volunteers. The presence and degree of lateral subluxation and tilt of the patella was assessed independently by three radiologists, and discrepancies ...

OBJECTIVE: To develop a scoring system for quantifying osteoarthritic changes of the knee as identified by magnetic resonance (MR) imaging, and to determine its inter- and intra-observer reproducibility, in order to monitor medical therapy in research studies. DESIGN AND PATIENTS: Two independent observers evaluated 25 consecutive MR examinations of the ...

BACKGROUND: Accurate alignment of the components in total knee arthroplasty is important. By use of postoperative CT controls, we studied the ability of a robotic effector to accurately place and align total knee arthroplasty (TKA) components according to a purely CT-based preoperative plan. PATIENTS AND METHODS: Robotic TKA was performed ...

The authors develop 3-D models of the pediatric knee from magnetic resonance imaging (MRI) image files, with the goal of minimizing injury to the pediatric growth plate during surgery. Computerized tomography (CT) scans have better resolution and contrast between bone and soft tissue than MRI scans; however, surgeons rely upon ...

A 27-year-old man, while serving in the armed forces, presented with complaints of right knee pain of 3 months duration. The patient reported pain localized on the lateral side of the right knee, especially during long-distance walking and stair climbing, and a feeling of giving way. There was no history ...

OBJECTIVE: Osteoarthritis (OA) is a major cause of disability and represents the most common disease in the aging population. Although the course of the disease is generally assessed using standard radiographic images, biochemical markers may be employed to detect the disease and determine the degree of severity. We developed an ...

BACKGROUND: The relation between knee meniscal structural damage and cartilage degradation is plausible but not yet clearly proven. OBJECTIVES: To quantitate the cartilage volume changes in knee osteoarthritis using magnetic resonance imaging (MRI), and determine whether meniscal alteration predicts cartilage volume loss over time. METHODS: 32 patients meeting ACR criteria ...

The objective is to evaluate the prevalence and morphology of recesses along the posterior margin of the infrapatellar fat pad on routine MR imaging of the knee. MR images of 213 knees in 204 consecutive individuals were evaluated with regard to the prevalence and morphology of recesses (a "suprahoffatic" recess ...

To evaluate the efficacy of MR imaging in the diagnosis and classification of meniscal tear of the knee joint, we retrospectively characterized the MR features of 78 meniscal tears in 148 patients according to the Mesgarzadeh's criteria. The results showed that the sensitivity and specificity for meniscal tears were 92% ...

PURPOSE: The purpose of this study was to compare the accuracy of clinical examination versus magnetic resonance imaging (MRI) in diagnosing meniscal and anterior cruciate ligament (ACL) pathology. TYPE OF STUDY: Prospective, longitudinal study. METHODS: Between August 2001 and December 2001, we prospectively evaluated 50 consecutive patients (37 male, 13 ...

Computed tomographic (CT) imaging of eight normal cadaveric canine stifles was performed before and after intra-articular administration of iodinated contrast medium. Transverse CT images were reconstructed in dorsal, parasagittal, and oblique planes. The following ligamentous structures were identified on transverse CT images in all stifles: cranial cruciate ligament, caudal cruciate ...

We report on the case of an 86-year-old woman who rapidly became unable to stand and walk because of jerky movements, suggesting a clinical diagnosis of myoclonus. It was observed that both unexpected and expected stimuli (audiogenic, tactile, or visual) triggered the myoclonic jerks. Electrophysiological exploration, including a coupled EEG-EMG ...

This review illustrates the radiographic and magnetic resonance imaging (MRI) appearances of a variety of entities that result in surface contour abnormalities of the distal femur. Such abnormalities may result from developmental variants expressed in the growing skeleton, from trauma, or from cortically-based tumours. As the number of MRI examinations ...

PURPOSE: To evaluate intravenously administered ultrasmall superparamagnetic iron oxide (USPIO) as a marker of macrophage activity in an experimental rabbit model of antigen-induced arthritis. MATERIALS AND METHODS: Unilateral arthritis was induced by means of intraarticular injection of methylated bovine serum albumin in 10 knees of 10 rabbits that had been ...

OBJECTIVE: The purpose of our study was twofold: to better understand the relationship between medial meniscal extrusion (MME) and degenerative joint disease (DJD), and to determine whether a relationship exists between MME and medial meniscal root (MMR) pathology, radial tear and joint effusion. DESIGN AND PATIENTS: Two hundred and five ...

A controlled study, comparing computer- and conventional jig-assisted total knee replacement in six cadavers is presented. In order to provide a quantitative assessment of the alignment of the replacements, a CT-based technique which measures seven parameters of alignment has been devised and used. In this a multi-slice CT machine scanned ...

BACKGROUND: Several techniques have been described for reconstruction of the medial patellofemoral ligament. However, the isometry of the medial patellofemoral ligament has not been studied. PURPOSE: To define the anatomy and isometry of the medial patellofemoral ligament. STUDY TYPE: Cadaveric study. METHODS: The authors dissected the medial patellofemoral ligament in ...

BACKGROUND: Magnetic resonance (MR) imaging is a useful diagnostic tool for the assessment of knee joint injury. Anterior cruciate ligament repair is a commonly performed orthopaedic procedure. This paper examines the concordance between MR imaging and arthroscopic findings. METHODS: Between February, 1996 and February, 1998, 48 patients who underwent magnetic ...

OBJECTIVE: The purpose of this study was to determine the reliability of standard axial MR images alone in the diagnosis of meniscal tears of the knee and in combination with other imaging planes. MATERIALS AND METHODS: Sixty-two patients (55 men, seven women; age range, 23-68 years) with a prior MRI ...

A technique using magnetic resonance imaging (MRI) is proposed for analysis of knee motion that is practical in the clinical situation. T1 weighted fast spin echo (FSE) and spoiled gradient echo (GE) sequences were compared to image both knees at 15 degrees intervals from 0 degrees to 90 degrees flexion, ...

OBJECTIVE: To evaluate the presence, location, and dimensions of the deep infrapatellar bursa on routine magnetic resonance (MR) imaging of the knee. METHODS: The study group consisted of 213 knees in 204 consecutive individuals who had undergone routine MR imaging examination of the knee within a 365-day period. Magnetic resonance ...

Anterior knee pain is a common symptom, which may have a large variety of causes including patellofemoral pathologies. Patellofemoral maltracking refers to dynamic abnormality of patellofemoral alignment and has been measured using plain film, computed tomography (CT) and magnetic resonance imaging (MRI) using static and kinematic techniques. Patellar dislocation is ...

OBJECTIVE: To determine the range of the patellar tendon length to patellar length ratio on magnetic resonance imaging (MRI) of the knee in order to aid in the establishment of MRI criteria for patella alta and baja. PATIENTS: Two hundred and forty-five patients ages 6-85 (mean 44) years who went ...

OBJECTIVE: Simultaneous acquisition of spatial harmonics (SMASH) is a parallel-imaging technique that uses fewer echoes than conventional techniques to obtain the desired resolution. Images are produced in a shorter time period using the SMASH technique than conventional techniques. This study assesses the usefulness of the SMASH technique in the MRI ...

OBJECTIVE: To prospectively investigate the healing process of meniscal repair with plain magnetic resonance imaging (MRI) and indirect MR arthrography and to compare the two methods. MATERIALS AND METHODS: Twenty patients with an arthroscopic meniscal repair without clinical symptoms underwent conventional and indirect MR arthrography of the affected knee, 3, ...

BACKGROUND: This study was initiated to evaluate the long-term outcome of meniscal sutures and to correlate clinical findings with MRI findings. We were interested to see if a clinically healed meniscus also showed as such on MRI and if degenerative changes were present PATIENTS AND METHODS: We studied prospectively 13 ...

OBJECTIVE: The purpose of this investigation was to characterize the MRI appearance of the quadriceps fat pad and to correlate the findings with other knee abnormalities, anatomic measurements of the extensor mechanism, and findings from history and at physical examination. MATERIALS AND METHODS: Ninety-two consecutive knee MRI examinations from 84 ...

OBJECTIVE: This study was performed with the aim of evaluating the usefulness of 3 dimensional double-echo steady state sequences in examining the internal derangements of the knee. Arthroscopy was used as a referral standard. METHODS: The study was performed in the Radiology and Arthroscopy Departments of King's College Hospital, London, ...

PURPOSE: To carry out a modern diagnostic survey among patients with a clinical and radiological diagnosis of early osteoarthritis of the knee. MATERIALS AND METHODS: A magnetic resonance imaging survey was performed on 70 patients (82 knees) with a mean age of 59 years. (range, 40-71 years) who had chronic ...