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To determine the frequency of non-diagnostic and discordant results from bone and soft tissue biopsies performed at our institution over a 3-year period and to investigate whether implementation of a weekly musculoskeletal radiology-pathology correlation conference decreased the time to appropriate patient management in cases of discordance. Consecutive image-guided core needle biopsy results obtained over a 12 month period of time were reviewed in a retrospective fashion. Following implementation of the correlation conference, subsequent consecutive image-guided core needle biopsy results obtained over a 26 month period of time were reviewed in a prospective fashion. For non-diagnostic and discordant cases, the time in days from date of availability of the biopsy result to date of documentation of a specific follow-up action plan was recorded. Diagnostic yield was 96.5% and 94.9% for the retrospective and prospective periods, respectively. There were four discordant results in the retrospective cohort (1.7%) and seven discordant results in the prospective cohort (2.1%). Following implementation of the weekly correlation conference, there was significant decrease (p

Soft-tissue sarcoma requires aggressive treatment, often with a combination of radiation therapy, chemotherapy, and surgical resection. Even after multimodality treatment, local recurrence is common, and regular follow-up imaging at short intervals is required. Interpretation of posttreatment magnetic resonance (MR) images may be complicated by changes in the surgical bed or treatment field. The challenge of distinguishing posttreatment change from recurrent tumor may be minimized by using an organized, systematic approach to imaging, with emphasis on the patient's clinical and surgical history and a review of pretreatment images. Common changes that result from radiation therapy include soft-tissue trabeculation, increased fatty marrow, and focal marrow abnormalities. Rarely, radiation-induced malignancies may develop within the treatment field. Chemotherapy also influences posttreatment imaging appearance. Occasionally, it causes a substantial increase in tumor size that is a result of chemotherapy-induced hemorrhage. Although myocutaneous flaps used in reconstructive surgery may mimic a mass, they demonstrate time-dependent changes in size, signal intensity, and enhancement on MR images. Recurrent tumor is characterized by the presence of a discrete nodule or mass with signal characteristics that typically mirror those of the original tumor. MR imaging sequences such as unenhanced T1-weighted fat-suppressed and gradient-echo sequences may help differentiate posttreatment hemorrhage from local tumor recurrence. A consistent imaging approach combined with a detailed knowledge of the patient's history, familiarity with pretreatment images, and an understanding of the various posttreatment changes enables optimal monitoring of the treatment bed and maximizes accuracy in the detection of recurrence.

Idiopathic retroperitoneal fibrosis is an uncommon disease characterized by periaortic inflammation with gradual fibrosis and distortion of retroperitoneal structures such as the ureter. Several earlier case reports have documented hypermetabolic retroperitoneal activity on fluorodeoxyglucose positron emission tomography (FDG PET) in patients with active disease, and a decrease in the activity following immunosuppressive therapy. We report FDG PET positive findings in three patients presenting with active retroperitoneal fibrosis. In two cases, enhancing periaortic soft tissue seen on computed tomography (CT) markedly diminished following immunosuppressive therapy. In one patient, repeat FDG PET was performed following immunosuppressive therapy, with complete resolution of the retroperitoneal FDG avidity. We suggest that FDG PET may play a useful adjunct to anatomic imaging and serum inflammatory markers in assessing the severity of inflammation in retroperitoneal fibrosis, and in assessing the likelihood of response to immunosuppressive therapy. FDG PET may also be used in follow-up to assess therapeutic response if CT findings are unclear.

Cystic lesions around the knee comprise a diverse group of entities, ranging from benign cysts to complications of underlying diseases such as infection, arthritis, and malignancy. Their diverse causes result in varied prognoses and therapeutic options. Although the presentation of cystic masses may be similar, their management may differ, thus highlighting the importance of appropriate categorization. MR aids in the characterization of lesions by first localizing them, and then defining their relationship with adjacent structures and identifying any additional abnormalities. For the purpose of this article, the authors limit the scope of their discussion to benign cysts, ganglia, and bursae about the knee.

The knee joint remains the articulation most frequently assessed by MR imaging, and osseous tumor and tumor-like lesions are not uncommon incidental imaging findings. This article reviews the most commonly encountered incidental lesions, emphasizing the characteristic MR imaging features. It is intended not as a complete review of the imaging findings associated with these lesions but as a summary, highlighting the MR imaging features that are most useful in suggesting a specific diagnosis. The authors organize incidental lesions into the following broad categories: cartilaginous, fibro-osseous, and degenerative. They do not address those lesions that are typically symptomatic and, as a result, likely to be directly related to the patients' clinical presentation and subsequent imaging.

Bone graft materials are widely used in reconstructive orthopedic procedures to promote new bone formation and bone healing, provide a substrate and scaffolding for development of bone structure, and function as a means for direct antibiotic delivery. Bone graft materials include autografts, allografts, and synthetic substitutes. An autograft (from the patient's own bone) supplies both bone volume and osteogenic cells capable of new bone formation. The imaging appearance of an autograft depends on its type, composition, and age. Autografts often appear as osseous fragments at radiography. At computed tomography (CT), autografts appear similar to the adjacent cortical bone. At magnetic resonance (MR) imaging, however, autografts have a variable appearance as a consequence of the viable marrow inside them, a feature not present in other graft materials. An allograft (from cadaveric bone) has an appearance similar to that of cortical bone on radiographs and CT images. An allograft in the form of bone chips or morsels does not show those features on radiographs and CT images, but instead appears as a conglomerate with medium to high opacity and attenuation within the bone defect. In the immediate postoperative period, allografts appear hypointense on both T1- and T2-weighted MR images. Hematopoietic tissue replaces the normal fatty marrow in the later phases of graft incorporation. Synthetic bone substitutes are much more variable in imaging appearance. As the use of bone allografts and synthetic substitutes increases, familiarity with postoperative imaging features is essential for differentiation between grafts and residual or recurrent disease.

Tumors involving the upper extremity are not uncommon. Although there is a wide variety of lesions that may occur in the hand and wrist, there are certain lesions which have a predilection for this location. This chapter will highlight the spectrum of imaging modalities available for the evaluation of upper extremity tumors, providing imaging guidelines for optimum selection of radiological examinations. It presents an overview of imaging of the hand and wrist, emphasizing the fundamental principles inherent to tumor imaging. Modalities reviewed include nuclear scintigraphy, positron emission tomography, sonography, computed tomography, arteriography, magnetic resonance imaging, and magnetic resonance angiography.

In conclusion, a wide variety of tumors and tumor-like conditions have a predilection for the hip. The imaging evaluation of these lesions begins with radiographs. Radiographs can depict the extent of disease; any characteristic calcifications; and osseous changes, such as remodeling,periosteal reaction, or destruction. MR imaging has emerged as the preferred imaging modality of choice for evaluating osseous and soft tissue masses of the hip by providing information for diagnosis and staging. The MR imaging signal characteristics and enhancement patterns of malignant and benign hip tumors permit specific diagnoses in some cases. Synovial-based tumor-like processes of the hip can be characterized by MR signal characteristics, such as the hemosiderin within PVNS or the cartilage within synovial chondromatosis. Finally, MR imaging can serve to exclude underlying osseous or soft tissue tumors when radiographs display aggressive features of tumor-like processes.

A rare case of neuroendocrine tumor of the uterus is presented. Magnetic resonance imaging (MRI) demonstrated diffuse enlargement of the uterus without a discrete mass. The vessels in the myometrium were not distorted. Histologically, tumor cells diffusely infiltrated the myometrium as well

Tumors involving the upper extremity are common. Although there are a wide variety of lesions that may occur in the hand and wrist, certain lesions have a predilection for this location. This article highlights the spectrum of imaging modalities available for the evaluation of upper extremity tumors, providing guidelines for optimum selection of radiologic examinations while emphasizing the fundamental principles inherent to tumor imaging.

OBJECTIVE. We sought to describe the radiographic and imaging features of cherubism.CONCLUSION. Cherubism is a rare osseous disorder of children and adolescents. Although the radiologic characteristics of cherubism are not pathognomonic, the diagnosis is strongly suggested by bilateral relatively symmetric jaw involvement that is limited to the maxilla and mandible. Imaging typically shows expansile remodeling of the involved bones, thinning of the cortexes, and multilocular radiolucencies with a coarse trabecular pattern.

OBJECTIVE. The objective of this article is to define the imaging characteristics of spindle cell lipoma on MRI and CT.CONCLUSION. The diagnosis of spindle cell lipoma should be suggested when a well-defined complex fatty mass is found in the subcutis of a middle-aged man, especially if the mass is localized to the posterior neck. Intense enhancement of the nonadipose component further supports this diagnosis.

The key to adequate and accurate evaluation, diagnosis, and treatment of bone tumors is an organized and integrated approach involving the surgeon, radiologist, and pathologist. The radiologist plays not only a valuable role in the diagnosis and preoperative staging of bone tumors but may also play a role in biopsy and treatment. Despite the wide variety of imaging modalities available today, radiographs remain the mainstay in the evaluation of osseous neoplasms. Advanced imaging is. however. very useful for staging purposes and for characterization of the internal characteristics of tumors and may aid significantly in limiting the differential diagnosis. Although a detailed discussion of all ofthe various bone tumors of the lower extremities is beyond the scope of this article, an attempt is made to provide a framework for a rational and comprehensive approach to these complicated but relatively uncommon lesions. Certain lesions with unique characteristics are discussed to facilitate the diagnostic process.

The purpose of this study was to identify the characteristic imaging features of wooden foreign bodies.The imaging studies of 12 patients with surgically confirmed wooden foreign bodies were retrospectively reviewed. The study group consisted of seven females and five males, 10-65 years old (mean age, 36 years). All patients underwent radiography. Nine patients were evaluated with sonography, eight with MR imaging, three with CT, and one with CT arthrography. Gadolinium-enhanced MR imaging was performed in six patients. Three patients presented with a draining sinus and nine with painful swelling. Only three patients presented with a history of penetrating injury.Lesions were located in the foot (n = 4), hand (n = 3), thigh (n = 2), calf (n = 2), and elbow (n = 1). Radiographs failed to reveal the retained foreign bodies in all patients. With MR imaging, wooden foreign bodies displayed a variable signal intensity that was equal to or less than that of skeletal muscle on both T1- and T2-weighted images. MR imaging showed the surrounding inflammatory response in all patients. CT showed the retained wood as linear cylindric foci of increased attenuation. Wood was highly echogenic and revealed pronounced acoustic shadowing on sonography. Arthrography in one patient showed an associated reactive synovitis.The imaging appearance of wooden foreign bodies is variable; however, imaging can be quite specific, and when taken in the appropriate clinical setting, the imaging should reliably suggest the diagnosis. Sonography is frequently underused but proved most useful for the evaluation of retained wooden foreign bodies.

The purpose of this study was to determine the relative prevalence of the sclerosing variant of well-differentiated liposarcoma at one institution and to elucidate the CT and MRI characteristics of this subtype of well-differentiated liposarcoma.A retrospective computerized search was conducted to calculate the relative prevalence of the sclerosing variant of well-differentiated liposarcoma among all well-differentiated liposarcoma subtypes at one institution. The MRI and CT features of a total of 19 cases of pathologically proven sclerosing variant of well-differentiated liposarcoma were evaluated (seven identified from the study institution database and 12 cases contributed by other institutions).The cases of a total of 36 patients with well-differentiated liposarcoma were identified in the pathology database; six (17%) cases had evidence of dedifferentiation. Seven (19%) cases of sclerosing variant of well-differentiated liposarcoma were identified. Of these, three (43%) had evidence of dedifferentiation. On images, the sclerosing variant of well-differentiated liposarcoma typically presented as a large (average, 16.6 cm) well-circumscribed heterogeneous mass most commonly situated in the retroperitoneum (58%). Sixteen of the 19 tumors evaluated (84%) had predominantly well-circumscribed margins. Tumor composition ranged from predominantly fatty to entirely devoid of macroscopic fat; only three (16%) were composed of more than 75% fat. Variable amounts of nonlipomatous elements were identified in all cases. Enhancement of these elements was evident at CT or MRI in all 14 cases in which enhancement could be reliably assessed.The sclerosing variant of well-differentiated liposarcoma should be included in the differential diagnosis of any well-circumscribed lipomatous mass containing variable amounts of nonlipomatous elements, particularly when located in the retroperitoneum. Unlike other subtypes of well-differentiated liposarcoma, the sclerosing variant is less likely to be composed predominantly of fat and may be associated with an increased propensity for dedifferentiation.

Posttreatment imaging is important to ensure early detection of oncological complications, and appropriate timing and frequency is an important consideration, especially in high-risk patients. Focused magnetic resonance (MR) imaging is the preferred modality for detection of local recurrence of soft tissue tumors and is also used in high-risk osteosarcoma. Although posttreatment changes can mimic or obscure local recurrence on MR imaging, a systematic approach and knowledge of the features of recurrence versus therapeutic change allows differentiation in almost all cases. Positron emission tomography/computed tomography is also emerging as an important problem-solving tool in local recurrence and in metastatic surveillance.

We report a case of sudden onset of deep peroneal neuropathy resulting from a ganglion cyst. Electrophysiology demonstrated a severe deep peroneal neuropathy with axonal loss and probably proximal conduction block. Magnetic resonance imaging demonstrated a mass arising from the proximal tibiofibular joint extending along the peroneal nerve. Surgical resection of the ganglion resulted in gradual improvement of strength. Peroneal nerve ganglia should be considered in the evaluation of patients with sudden painless foot drop.

The purposes of this study were to describe the imaging appearance of diffuse neurofibroma in 10 patients and to summarize demographic data on a large group of patients.Retrospective review of the pathology and radiology teaching databases at two institutions yielded the cases of 339 patients with a pathologic diagnosis of diffuse neurofibroma. Diagnostic-quality images were available for 10 patients. Images from MRI (n = 8), CT (n = 5), and sonographic (n = 1) examinations were evaluated for lesion location, size, depth of involvement, growth pattern, and intrinsic signal intensity, attenuation, or echogenicity. Demographic information, associated lesions, and tumor location were recorded for all patients.Among 10 patients with images, eight of whom had neurofibromatosis, diffuse neurofibroma involved the skin and subcutaneous tissues (n = 9) and frequently extended to the fascia over muscle (n = 6). Plaquelike (n = 5) and infiltrative (n = 3) growth patterns were most common. One lesion had a mixed growth pattern. Prominent internal vascularity was common (n = 5). MRI signal intensity and CT attenuation were typically nonspecific. Enhancement was intense in all five patients with contrast-enhanced MR examinations. Including patients with and those without images, 349 diffuse neurofibromas were present in 339 patients. The mean patient age was 35.1 years. Lesions involved the extremities (n = 120), trunk (n = 122), head and neck (n = 98), and deep structures (n = 9).Diffuse neurofibroma frequently grows as a plaquelike or infiltrative lesion involving the skin and subcutaneous tissues. Prominent internal vascularity is common. There is a much wider soft-tissue and age distribution and association with neurofibromatosis than previously reported.

Recent advances in PET technology and applications have led to a proliferation in PET and PET/CT imaging, allowing correlation of both physiologic and anatomic information. This has also led to new and innovative ways to utilize PET imaging for the evaluation of musculoskeletal neoplasm. Currently, the most widely utilized musculoskeletal application of F-18 FDG-PET imaging is for the detection and characterization of osseous metastatic disease. The other notable potential role for FDG-PET imaging is for staging and restaging of primary bone tumors and soft tissue sarcomas. Precise staging and restaging of musculoskeletal neoplasm is critical to optimize treatment planning and to accurately determine patient prognosis. FDG-PET is also useful in evaluating response to therapy for musculoskeletal tumors. The future likely holds even more unique and potentially quite useful applications of PET imaging for primary osseous and soft tumors. This article will review the common and potentially useful applications of F-18 FDG-PET imaging for evaluating musculoskeletal tumors and malignancy.

The objective was to evaluate the piriformis muscles and their relationship to the sacral nerve roots on T1-weighted MRI in patients with no history or clinical suspicion of piriformis syndrome.Axial oblique and sagittal T1-weighted images of the sacrum were obtained in 100 sequential patients (200 pairs of sacral roots) undergoing routine MRI examinations. The relationship of the sacral nerve roots to the piriformis muscles and piriformis muscle size were evaluated, as were clinical symptoms via a questionnaire.The S1 nerve roots were located above the piriformis muscle in 99.5% of cases (n=199). The S2 nerve roots were located above the piriformis muscle in 25% of cases (n=50), and traversed the muscle in 75% (n=150). The S3 nerve roots were located above the piriformis muscle in 0.5% of cases (n=1), below the muscle in 2.5% (n=5), and traversed the muscle in 97% (n=194). The S4 nerve roots were located below the muscle in 95% (n=190). The piriformis muscles ranged in size from 0.8-3.2 cm, with an average size of 1.9 cm. Nineteen percent of patients had greater than 3 mm of asymmetry in the size of the piriformis muscle, with a maximum asymmetry of 8 mm noted.The S1 nerve roots course above the piriformis muscle in more than 99% of patients. The S2 roots traverse the piriformis muscle in 75% of patients. The S3 nerve roots traverse the piriformis muscle in 97% of patients. Piriformis muscle size asymmetry is common, with muscle asymmetry of up to 8 mm identified.

Although percutaneous needle biopsies are typically safe, there are possible musculoskeletal needle biopsy complications. Preoperative consultation with orthopaedic surgeons providing treatment is appropriate for radiologists performing percutaneous tumor biopsies because biopsy tracts need to be resected along with the specimens in cases of primary malignancy. Knowledge of compartmental anatomy may help avoid complications related to poorly planned or executed needle biopsies that may compromise the ability of the surgeon to perform a limb-sparing resection.

Despite tremendous technical advances in spine surgery in recent decades, patients may experience residual or recurrent pain and other symptoms after such surgery. The standard history and physical examination have only limited utility for assessing the postoperative anatomy, and radiologists can play an important role in diagnosing complications and guiding postoperative care. To do so effectively, they must be familiar with the imaging features of successful and unsuccessful fusion, instrumentation fracture and loosening, complications due to faulty hardware placement, and postoperative infection. A basic knowledge of spinal biomechanics and common approaches to surgical instrumentation also may help radiologists anticipate and identify complications.

Injuries of the collateral ligaments of the metacarpophalangeal (MCP) joints of the hand require accurate diagnosis and prompt treatment to prevent loss of function. The most common and well-known collateral ligament injury is injury to the ulnar collateral ligament of the first MCP joint of the hand, often referred to as a gamekeeper injury. Although less common, injuries involving the collateral ligaments of the second through fifth digits and the radial collateral ligament of the first digit also occur. The diagnosis of collateral ligament injury is often made clinically, however, magnetic resonance imaging and magnetic resonance arthrography of the MCP joints can be very useful in the evaluation of severity of the injury. This provides important information for the hand surgeon and aids in treatment planning. Imaging of the collateral ligaments requires small fields of view and several technical considerations can provide improved image quality. These factors will be discussed and illustrated in this article.

The management of the postoperative shoulder has improved, in part because of advances in imaging techniques. As disability and pain may occur or persist after shoulder surgery, it is imperative that clinicians have a detailed anatomic delineation before further treatment. Variations in surgical techniques, surgical distortion of native anatomy, and metallic artifacts decrease the accuracy of postoperative imaging. Pitfalls may be avoided with knowledge of postoperative alterations of the rotator cuff, labrum and capsule.

Palmar fasciitis and polyarthritis syndrome (PFPAS) is an uncommon paraneoplastic syndrome associated with several malignant neoplasms. We identified 4 patients with PFPAS and ovarian carcinoma. Palmar fasciitis, at times severe, and inflammatory polyarthritis dominated the clinical presentation in all 4 patients. In 3 of our 4 patients the presentation of palmar fasciitis and inflammatory polyarthritis preceded the diagnosis of ovarian carcinoma. Magnetic resonance scanning and biopsy examination of palmar nodules in one patient revealed findings of inflammation and fibrosis. A literature review found 10 other cases of PFPAS associated with ovarian carcinoma. Improvement in palmar fasciitis and inflammatory arthritis often occurs after successful treatment of the ovarian carcinoma. Digital contractures, however, can persist. We recommend a gynecologic examination in any woman presenting with the sudden onset of unexplained hand pain, palmar inflammatory fasciitis, palmar fibromatosis, and digital contractures.

Lipoma is the most common soft-tissue tumor, with a wide spectrum of clinical presentations and imaging appearances. Several subtypes are described, ranging from lesions entirely composed of mature adipose tissue to tumors intimately associated with nonadipose tissue, to those composed of brown fat. The imaging appearance of these fatty masses is frequently sufficiently characteristic to allow a specific diagnosis. However, in other cases, although a specific diagnosis is not achievable, a meaningful limited differential diagnosis can be established. The purpose of this manuscript is to review the spectrum of benign fatty tumors highlighting the current classification system, clinical presentation and behavior, spectrum of imaging appearances, and treatment. The imaging review emphasizes computed tomography (CT) scanning and magnetic resonance (MR) imaging, differentiating radiologic features.

The current standard of practice for the detection of osseous metastatic disease is the conventional bone scan of the entire body using technetium-99m methylene diphosphonate (Tc-99m MDP). Although Tc-99m MDP scintigraphy is sensitive for the detection of advanced skeletal metastatic lesions, early involvement may be missed because this technique relies on the identification of the osteoblastic reaction of the involved bone rather than the detection the tumor itself. Positron emission tomography (PET) has proven to be the gold standard in metabolic imaging. Fluorine -18 deoxyglucose (FDG) provides a means of quantitating the glucose metabolism, with the amount of tracer accumulation reflecting the glucose metabolism: high-grade malignancies tend to have higher rates of glycolysis than do low-grade malignancies and benign lesions; therefore, high-grade malignancies have greater uptake of FDG than that of low-grade or benign lesions. Positron emission tomography has been shown to be superior to scintigraphy in the detection of metastases because it detects the presence of tumor directly by metabolic activity, rather than indirectly by showing tumor involvement due to increased bone mineral turnover. This has allowed the detection of metastatic foci earlier with PET than with bone scintigraphy. Although the spectrum of PET applications is unknown, it now is approved for the diagnosis, staging and restaging of many common malignancies and has shown efficacy for the detection of osseous metastasis from several malignancies including lung carcinoma, breast carcinoma, and lymphoma.

To review the reliability of computed tomographic (CT) and magnetic resonance (MR) imaging features in distinguishing lipoma and well-differentiated liposarcoma.CT (n= 29) and MR (n = 40) images and radiographs (n = 28) of 60 patients with histologically verified fatty tumors (35 lipomas and 25 well-differentiated liposarcomas) were retrospectively reviewed in 31 females and 29 males (mean age, 56 years; age range, 1-88 years). Images were assessed for adipose tissue content, and non-fatty component was classified (thin and/or thick septa and nodular and/or globular components) as absent, mild, moderate, or pronounced. Also assessed were signal intensity and tissue attenuation of the fatty components and non-adipose elements.Statistically significant imaging features favoring a diagnosis of liposarcoma included lesion larger than 10 cm (P.001), presence of thick septa (P =.001), presence of globular and/or nodular non-adipose areas (P =.003) or masses (P =.001), and lesion less than 75% fat (P.001). The most statistically significant radiologic predictors of malignancy were male sex, presence of thick septa, and associated non-adipose masses, which increased the likelihood of malignancy by 13-, nine-, and 32-fold, respectively. Both lipoma and liposarcoma demonstrated thin septa and regions of increased signal intensity on fluid-sensitive MR images.A significant number of lipomas will have prominent non-adipose areas and will demonstrate an imaging appearance traditionally ascribed to well-differentiated liposarcoma. Features that suggest malignancy include increased patient age, large lesion size, presence of thick septa, presence of nodular and/or globular or non-adipose mass-like areas, and decreased percentage of fat composition.

Loss of full extension after anterior cruciate ligament (ACL) reconstruction, with development of an audible and palpable "clunk" with terminal extension was first described by Jackson and Schaefer as "cyclops syndrome." This syndrome, which is the result of a fibrous nodule (termed a cyclops nodule), has recently been described in patients who have sustained ACL injury but have not undergone reconstructive surgery. From 2001 to 2006, the authors identified 10 patients (five women and five men, ages 27-76 years) with cyclops nodules seen at magnetic resonance (MR) imaging. All patients had a history of trauma but no history of ACL reconstruction. The cyclops lesions had a mean size of 16 x 12 x 11 mm, with 90% of them located just anterior to the distal ACL. MR imaging showed a well-defined, somewhat heterogeneous soft-tissue nodule with a signal intensity typically similar to that of skeletal muscle. The authors suspect that the cause of cyclops lesions that occur in the absence of ACL reconstruction is similar to that suggested in the classic postoperative patient. Cyclops syndrome should be suspected in any patient in whom an ACL nodule is identified at MR imaging, and similarly a cyclops nodule should be considered as a possible cause of loss of extension in any patient who has sustained ACL injury. Movies available at http://radiographics.rsnajnls.org/cgi/content/full/e26/DC1.