ACR Appropriateness Criteria® Chronic Hand and Wrist Pain: 2023 Update.

Chronic hand and wrist pain is a common presenting complaint. The intricate anatomy results in a variety of pain generators-multiple bones, articular cartilage, intrinsic ligaments, triangular fibrocartilage complex, joint capsules and synovium, tendons and tendon sheaths, muscles, and nerves-in a compact space. The need for imaging and the choice of the appropriate imaging modality are best determined by the patient's presentation, physical examination, and the clinician's working differential diagnosis. Radiography is usually appropriate as the initial imaging study in the evaluation of chronic hand or wrist pain. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Anatomical Proximity Between Sciatic Nerve and Ischial Spine and its Relationship to the Development of Deep Gluteal Pain Syndrome.

OBJECTIVE: Deep gluteal syndrome (DGS) is a medical diagnosis in which the pathoanatomy of the subgluteal space contributes to pain. The growing recognition that gluteal neuropathies can be associated with the presence of a bone-neural conflict with irritation or compression may allow us to shed some light on this pathology. This study aims to determine whether the location of the sciatic nerve in relation to the ischial spine contributes to the development of DGS. METHODS: The sciatic nerve - ischial spine relationship was analyzed based on magnetic resonance imaging (MRI) in 15 surgical patients who underwent piriformis release, and in 30 control patients who underwent MRI of the pelvis for reasons unrelated to sciatica. The sciatic nerve exit from the greater sciatic foramen was classified as either zone A (medial to the ischial spine); zone B (on the ischial spine); or zone C (lateral to the ischial spine). RESULTS: The sciatic nerve was significantly closer to the ischial spine in surgical patients than in MRI controls (P=0.014). When analyzing patients of similar age, sciatic nerves in surgical patients were significantly closer (P=0.0061) to the ischial spine, and located in zone B significantly more (P=0.0216) as compared to MRI controls. Patients who underwent surgery for piriformis release showed a significant decrease in pain postoperatively (P<0.0001). CONCLUSIONS: The results from this study suggest that the relationship between the ischial spine and sciatic nerve may play a role in the development of DGS. This may also help establish which patients would benefit more from surgical intervention.

Comparison of MRI and arthroscopy findings for transitional zone cartilage damage in the acetabulum of the hip joint.

OBJECTIVE: To assess the performance of morphologic and hypointense signal changes on MRI to predict grades and types of acetabular cartilage damage in the chondrolabral transitional zone (TZ) of the hip identified at arthroscopy. MATERIALS AND METHODS: This retrospective single-center study reviewed conventional 3T MRI hip studies from individuals with symptomatic femoroacetabular impingement (FAI) and subsequent hip arthroscopy surgery within 6 months. Independent review was made by three radiologists for the presence of morphologic damage or a hypointense signal lesion in the TZ on MRI. Fleiss' kappa statistic was used to assess inter-reader agreement. The degree of TZ surfacing damage (modified Outerbridge grades 1-4) and presence of non-surfacing wave sign at arthroscopic surgery were collected. Relationship between sensitivity and lesion grade was examined. RESULTS: One hundred thirty-six MRI hip studies from 40 males and 74 females were included (mean age 28.5 years, age range 13-54 years). MRI morphologic lesions had a sensitivity of 64.9-71.6% and specificity of 48.4-67.7% for arthroscopic surfacing lesions, with greater sensitivity seen for higher grade lesions. Low sensitivity was seen for wave sign lesions (34.5-51.7%). MRI hypointense signal lesions had a sensitivity of 26.3-62% and specificity of 43.8-78.0% for any lesion. Inter-reader agreement was moderate for morphologic lesions (k = 0.601) and poor for hypointense signal lesions (k = 0.097). CONCLUSION: Morphologic cartilage damage in the TZ on MRI had moderate sensitivity for any cartilage lesion, better sensitivity for higher grade lesions, and poor sensitivity for wave sign lesions. The diagnostic value of hypointense signal lesions was uncertain.

ACR Appropriateness Criteria® Imaging After Total Hip Arthroplasty.

This article reviews evidence for performing various imaging studies in patients with total hip prostheses. Routine follow-up is generally performed with radiography. Radiographs are also usually the initial imaging modality for patients with symptoms related to the prosthesis. Following acute injury with pain, noncontrast CT may add information to radiographic examination regarding the presence and location of a fracture, component stability, and bone stock. Image-guided joint aspiration, noncontrast MRI, and white blood cell scan and sulfur colloid scan of the hip, are usually appropriate studies for patients suspected of having periprosthetic infection. For evaluation of component loosening, wear, and/or osteolysis, noncontrast CT or MRI are usually appropriate studies. Noncontrast MRI is usually appropriate for identifying adverse reaction to metal debris related to metal-on-metal articulations. For assessing patients after hip arthroplasty, who have trochanteric pain and nondiagnostic radiographs, ultrasound, or MRI are usually appropriate studies. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

ACR Appropriateness Criteria® Imaging After Total Knee Arthroplasty: 2023 Update.

Total knee arthroplasty is the most commonly performed joint replacement procedure in the United States. This manuscript will discuss the recommended imaging modalities for six clinical variants; 1. follow-up of symptomatic or asymptomatic patients with a total knee arthroplasty. Initial imaging, 2. Suspected infection after total knee arthroplasty. Additional imaging following radiographs, 3. Pain after total knee arthroplasty. Infection excluded. Suspect aseptic loosening or osteolysis or instability. Additional imaging following radiographs, 4. Pain after total knee arthroplasty. Suspect periprosthetic or hardware fracture. Additional imaging following radiographs, 5. Pain after total knee arthroplasty. Measuring component rotation. Additional imaging following radiographs, and 6. Pain after total knee arthroplasty. Suspect periprosthetic soft-tissue abnormality unrelated to infection, including quadriceps or patellar tendinopathy. Additional imaging following radiographs. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

ACR Appropriateness Criteria® Chronic Extremity Joint Pain-Suspected Inflammatory Arthritis, Crystalline Arthritis, or Erosive Osteoarthritis: 2022 Update.

Evaluation for suspected inflammatory arthritis as a cause for chronic extremity joint pain often relies on imaging. It is essential that imaging results are interpreted in the context of clinical and serologic results to add specificity because there is significant overlap of imaging findings among the various types of arthritis. This document provides recommendations for imaging evaluation of specific types of inflammatory arthritis, including rheumatoid arthritis, seronegative spondyloarthropathy, gout, calcium pyrophosphate dihydrate disease (or pseudogout), and erosive osteoarthritis. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

ACR Appropriateness Criteria® Chronic Hip Pain: 2022 Update.

Chronic hip pain is a frequent chief complaint for adult patients who present for evaluation in a variety of clinical practice settings. Following a targeted history and physical examination, imaging plays a vital role in elucidating the etiologies of a patient's symptoms, as a wide spectrum of pathological entities may cause chronic hip pain. Radiography is usually the appropriate initial imaging test following a clinical examination. Depending on the clinical picture, advanced cross-sectional imaging may be subsequently performed for further evaluation. This documents provides best practice for the imaging workup of chronic hip pain in patients presenting with a variety of clinical scenarios. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Chronic Shoulder Pain: 2022 Update.

Chronic shoulder pain is an extremely common presenting complaint. Potential pain generators include the rotator cuff tendons, biceps tendon, labrum, glenohumeral articular cartilage, acromioclavicular joint, bones, suprascapular and axillary nerves, and the joint capsule/synovium. Radiographs are typically the initial imaging study obtained in patients with chronic shoulder pain. Further imaging may often be required, with modality chosen based on patient symptoms and physical examination findings, which may lead the clinician to suspect a specific pain generator. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Ultrasound-guided nerve block prior to biopsy of suspected neurogenic tumors: safety and feasibility in a pilot study.

OBJECTIVE: The aim of this study is to investigate the safety and feasibility of ultrasound-guided nerve block prior to biopsy of potentially neurogenic tumors. MATERIALS AND METHODS: A retrospective review of the medical record from June 2017 to June 2022 identified ultrasound-guided biopsies of potentially neurogenic tumors that were performed with a pre-procedural nerve block. Patient demographics, biopsy site, number of passes, needle gauge, use of sedation, pathology results, and procedural complications were recorded and summarized. RESULTS: The structured search found 16 patients that underwent biopsies of 18 potentially neurogenic tumors with the use of a pre-procedural nerve block at a variety of upper and lower extremity locations. Average patient age was 52 (range 18-78) and 9 patients (56%) were female. Of the 16 patients, 10 were performed without intravenous sedation. Three patients were unable to tolerate biopsy until a nerve block was used. All biopsies yielded a diagnostic sample with 13 of the tumors neurogenic in origin. One patient reported mild postprocedural pain which resolved with conservative treatment; no other complications were reported. CONCLUSION: Nerve block prior to ultrasound-guided biopsy of potentially neurogenic tumors is a safe and feasible technique. Further study is needed to determine the extent to which nerve block can decrease intra-procedural pain and reduce or eliminate the need for sedation during biopsy.

The posterior crescent sign on MRI and MR arthrography: is it a marker of hip dysplasia and instability?

OBJECTIVE: To evaluate the prevalence of the 'posterior crescent sign' in symptomatic patients referred for MRI/MR arthrogram of the hip and identify any correlation with imaging features of joint pathology. MATERIALS AND METHODS: Retrospective imaging assessment of a cohort of 1462 hips, from 1380 included MR examinations (82 bilateral) retrieved from a search of all examinations in patients 16-50 years old from June 2018 to June 2021, with median age 45.8 years (range 17.8-50.0) and 936 hips (64%) in women. Radiographic and MR findings related to hip dysplasia, femoroacetabular impingement and osteoarthritis were assessed. RESULTS: Fifty-one hips (3.5%) were positive for the posterior crescent sign, median age of 45.8 years (range 17.8-50.0) and 29 (58%) in women. Radiographic findings included the following: mean lateral centre edge angle (LCEA) 22.2° (± 7.8°) with LCEA < 20° in 15 (31%) and LCEA 20-25° in 17 (35%) and mean acetabular index (AI) of 13.1° (± 5.8°) with AI > 13° in 22 (45%). MR findings included the following: mean anterior acetabular sector angle (AASA) 54.3° (± 9.8°), mean posterior acetabular sector angle (PASA) 92.7° (± 7.0°), labral tear at 3-4 o'clock in 20 (39%), high-grade acetabular chondral loss in 42 (83%) and ligamentum teres abnormality in 20 (39%). CONCLUSION: The posterior crescent sign occurs in 3.5% of symptomatic young and middle-aged adults on MR. It is associated with overt and borderline hip dysplasia and other findings of hip instability. It is also associated with osteoarthritis in some cases and should be interpreted with caution in these patients.

ACR Appropriateness Criteria® Osteoporosis and Bone Mineral Density: 2022 Update.

Osteoporosis constitutes a significant public health risk. An estimated 10.2 million adults in the United States >50 years of age have osteoporosis, a systemic condition that weakens the bones increasing the susceptibility for fractures. Approximately one-half of women and nearly one-third of men >50 years of age will sustain an osteoporotic fracture. These fractures are associated with a decrease in quality of life, diminished physical function, and reduced independence. Dual-energy X-ray absorptiometry (DXA) is the primary imaging modality used to screen for osteoporosis in women >65 years of age and men >70 years of age. DXA may be used in patients <65 years of age to evaluate bone mass density if there are additional risk factors. In certain situations, vertebral fracture assessment and trabecular bone score may further predict fracture risk, particularly in patients who are not yet osteoporotic but are in the range of osteopenia. Quantitative CT is useful in patients with advanced degenerative changes in the spine. Given the proven efficacy of pharmacologic therapy, the role of imaging to appropriately identify and monitor high-risk individuals is critical in substantially reducing osteoporosis-associated morbidity and mortality, and reducing the considerable cost to the health care system. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Contrast-enhanced ultrasound-guided musculoskeletal biopsies: our experience and technique.

OBJECTIVE: To present our experience with contrast-enhanced ultrasound (CEUS)-guided musculoskeletal soft tissue biopsies in a busy interventional clinic. MATERIALS AND METHODS: After IRB approval was obtained and informed consent was waived, we retrospectively reviewed all CEUS-guided musculoskeletal biopsies performed from December 1, 2018 to March 2, 2020. Relevant pre-procedure imaging was reviewed. Number of samples, suspected necrosis on pre-procedure imaging, specimen adequacy for pathologic analysis, correlation with pathologic diagnosis of surgical resection specimens, and procedural complications were recorded. RESULTS: Thirty-six CEUS-guided musculoskeletal biopsies were performed in 32 patients (mean age 57, range 26-88; 22 males, 10 females). All procedures were performed using 16-gauge biopsy needles, and all procedures provided adequate samples for pathologic analysis as per the final pathology report. Between two and seven core specimens were obtained (mean 3.7). In 30/36 cases (83%), a contrast-enhanced MRI was obtained prior to biopsy, and 10/30 (33%) of these cases showed imaging features suspicious for necrosis. In 15/36 cases, surgical resection was performed, and the core biopsy and surgical resection specimens were concordant in 14/15 cases (93%). One patient noted transient leg discomfort at the time of microbubble bursting. Otherwise, no adverse reactions or procedural complications were observed. CONCLUSION: CEUS is an accurate way to safely target representative areas of soft tissue lesions for biopsy and can be implemented in a busy interventional clinic. Our early experience has shown this to be a promising technique, especially in targeting representative areas of heterogeneous lesions and lesions with areas of suspected necrosis on prior imaging.

Microinstability of the hip: a systematic review of the imaging findings.

OBJECTIVES: To undertake a systematic review of the morphologic features associated with hip microinstability and determine whether there are suggestive or diagnostic imaging findings. METHODS: Four electronic databases were searched up to September 2019 to identify original research reporting morphologic features in individuals with either a clinical diagnosis of hip microinstability (instability without overt subluxation/dislocation) or those with symptomatic laxity demonstrated on imaging (increased femoral head translation/distraction or capsular volume). Studies focussing on individuals with pre-existing hip conditions (including definite dysplasia (lateral centre edge angle < 20°), significant trauma, previous dislocation or surgery were excluded. Methodological quality was assessed by the Quality Assessment of Diagnostic Accuracy Studies 2 tool. RESULTS: Twenty-two studies met inclusion criteria (clinical diagnosis of microinstability n = 15 and demonstration of laxity n = 7). Imaging information gathered from the studies includes radiographs (n = 14), MRI (n = 6), MR arthrography (n = 4), CT (n = 1) and intraoperative examination. Most studies exhibited design features associated with an overall high or unclear risk of bias. Some dysplastic features are associated with microinstability or laxity reference measures; however, microinstability is frequently diagnosed in those with a lateral centre edge angle > 25°. Other associated imaging findings reported include impingement morphology, anterior labral tearing, femoral head chondral injury, ligamentum teres tears and capsular attenuation. CONCLUSIONS: The current literature does not provide strong evidence for imaging features diagnostic of microinstability. In the appropriate clinical context, dysplastic morphology, anterior labral tears and ligamentum teres tears may be suggestive of this condition although further research is needed to confirm this. PROSPERO REGISTRATION: CRD42019122406.

Overuse Injuries of the Shoulder.

This article discusses the most common and important overuse injuries of the shoulder with attention to MR imaging and ultrasound findings. Pathologic conditions occurring in athletes and nonathletes are included, with review of relevant anatomy, predisposing factors, and treatment considerations. Specific overuse injuries involving the rotator cuff, long head of the biceps tendon, and subacromial-subdeltoid bursa are reviewed. Impingement syndromes of the shoulder, Little Leaguer's shoulder, and stress-induced distal clavicular osteolysis are also discussed.

Incidence and implications of fracture in core muscle injury.

OBJECTIVE: To determine the pubic bone fracture incidence and associated injury patterns in patients with core muscle injury. MATERIALS AND METHODS: Ninety-three consecutive patients with core muscle injury protocol MRI showing rectus abdominis-adductor longus aponeurotic plate injuries from June 2007 through August 2017 were independently analyzed in blinded fashion by two musculoskeletal radiologists for the presence or absence of pubic bone fracture. A variety of other osseous and soft tissue injury characteristics were recorded. Pain duration prior to MRI and return to play time were taken from the clinical record. Statistical analysis included fracture incidence as well as the association of fracture with other injury characteristics, duration of pain, and return to play time. RESULTS: Eighty-seven men and six women with a mean age of 34.4 years (range, 16-66 years) were included in the study cohort. Overall fracture incidence was 18.3% (17/93) including 13 fatigue fractures of the pubic body and four elevated cortical fractures/fragments. After correction for multiple comparisons, no strong association was identified with osseous or soft tissue injury characteristics, pain duration, or return to play time. CONCLUSIONS: Pubic fractures-particularly fatigue fractures-are a common co-existing injury in patients with a wide range of core muscle injury patterns. The presence of fracture did not have a strong correlation with injury patterns, pain duration, or return to play time but may have implications for patient management.

Juvenile Osteochondritis Dissecans: Cartilage T2 Mapping of Stable Medial Femoral Condyle Lesions.

Purpose To determine whether a T2 mapping sequence could depict early changes in the composition and microstructure of cartilage overlying stable lesions of the medial femoral condyle in patients with juvenile osteochondritis dissecans (JOCD). Materials and Methods This retrospective study analyzed a sagittal T2 mapping sequence performed between September 1, 2015, and March 31, 2017, on 16 patients (10 boys and six girls; median age, 11.5 years) with 18 stable medial femoral condyle JOCD lesions and 18 age-, sex-, and skeletal maturation-matched control participants (11 boys and seven girls; median age, 11.5 years). Cartilage T2 values were quantitatively measured within regions of interest placed around the cartilage within and overlying the JOCD lesion in patients with JOCD and around the cartilage on the weight-bearing medial femoral condyle in patients with JOCD and controls. Wilcoxon signed rank and Wilcoxon rank sum tests were used to compare T2 values. Results T2 values were significantly higher (P < .001) for cartilage within the JOCD lesion than for cartilage overlying the JOCD lesion in patients with JOCD. However, there were no significant differences in T2 values between cartilage overlying the JOCD lesion and cartilage on the weight-bearing medial femoral condyle in patients with JOCD (P = .67) or in T2 values of the cartilage on the weight-bearing medial femoral condyle between patients with JOCD and controls (P = .30). Conclusion There were no significant quantifiable differences in T2 values of cartilage overlying stable JOCD lesions and normal cartilage on the medial femoral condyle, suggesting no substantial changes in cartilage composition and microstructure.

Magnetic Resonance Imaging Appearance of the Hip Musculature After Arthroscopic Labral-Level Iliopsoas Tenotomies.

BACKGROUND: Iliopsoas (IP) muscle atrophy is a known consequence of open IP tenotomy, but the severity of IP muscle atrophy that occurs after arthroscopic labral-level IP tenotomies has not been documented. PURPOSE: To document the severity of muscle atrophy that occurs in the iliacus, psoas, and adjacent hip musculature after arthroscopic labral-level IP tenotomy. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Twenty-eight patients who had magnetic resonance arthrograms (MRAs) obtained prior to and 3 months to 5 years after arthroscopic labral-level IP tenotomies are the basis of this report. The pre- and postoperative MRAs of each patient were examined in consensus by 2 musculoskeletal radiologists who graded the postoperative muscle atrophy from 0 (no fatty infiltration) to 4 (>75% fatty infiltration) and noted any compensatory muscle hypertrophy or abnormal IP tendon morphology. Patients also were assessed with the Byrd 100-point modified Harris Hip Scoring system (MHHS) preoperatively and at the time of their postoperative MRA. RESULTS: Postoperative MRAs were obtained on average 1.7 years (range, 3 months to 5 years) after hip arthroscopy. None of the patients had muscle atrophy on their preoperative MRAs. In contrast, 89% of patients had iliacus and psoas muscle atrophy on their postoperative MRAs, but only 2 (7%) developed grade 4 atrophy, and the majority (64%) had either grade 1 (n = 15) or no atrophy (n = 3). In addition, there were no significant differences in the MHHS of the patients with mild (grades 0-1), moderate (grades 2-3), or severe (grade 4) postoperative atrophy. Postoperative MRAs also demonstrated low-grade atrophy (grades 1-2) in the quadratus femoris (n = 5) and rectus femoris (n = 1) muscles, and 16 patients (57%) had distortion of the tendon, but none had a gap in their tendon. CONCLUSION: A majority of patients (89%) developed IP muscle atrophy after arthroscopic labral-level IP tenotomies, and although this percentage was similar (89% vs 90%) to that reported with lesser trochanteric IP tenotomies, the patients did not (1) develop atrophy of the gluteus maximus and vastus lateralis muscles, (2) have chronic IP tendon disruption, or (3) develop the severity of IP atrophy (55% grade 4 vs 7% grade 4) that has been reported after arthroscopic lesser trochanteric IP tenotomies.

Evaluation of the Articular Cartilage of the Knee Joint Using an Isotropic Resolution 3D Fast Spin-Echo Sequence With Conventional and Radial Reformatted Images.

OBJECTIVE: The purpose of this study was to determine whether the use of radial reformatted images could improve the diagnostic performance of a 3D fast spin-echo (FSE) sequence for detecting surgically confirmed cartilage lesions within the knee joint. MATERIALS AND METHODS: An MRI examination consisting of five 2D FSE sequences and a sagittal 3D FSE sequence was performed at 3 T on the knee joint of 150 patients who underwent subsequent knee arthroscopy, which included grading of the articular cartilage. Conventional axial, sagittal, and coronal reformatted images and radial reformatted images were created from the 3D FSE source data. Two musculoskeletal radiologists independently used the 2D FSE sequences, the 3D FSE sequence with conventional reformatted images only, and the 3D FSE sequence with both radial and conventional reformatted images at three separate sessions to grade each articular surface of the knee joint. McNemar tests were used to compare diagnostic performance for detecting cartilage lesions using arthroscopy as the reference standard. RESULTS: The 3D FSE sequence with radial and conventional reformatted images had higher sensitivity (p < 0.001) and similar specificity (p = 0.73) to the 2D FSE sequences for detecting cartilage lesions and higher sensitivity (p < 0.001) and specificity (p = 0.002) than the 3D FSE sequence with conventional reformatted images for detecting cartilage lesions. The 3D FSE sequence with conventional reformatted images had similar sensitivity (p = 0.93) and lower specificity (p = 0.005) than did the 2D FSE sequences for detecting cartilage lesions. CONCLUSION: A 3D FSE sequence had improved diagnostic performance compared with 2D FSE sequences for detecting cartilage lesions within the knee joint but only when using both radial and conventional reformatted images for cartilage evaluation.