Faculty Bibliography

OBJECTIVE:The purpose of this study was to use the Kellgren-Lawrence, Ahlback, and Brandt grading scales to correlate radiographic grade of osteoarthritis with the actual degree of articular cartilage degeneration within the tibiofemoral joint in patients with chronic knee pain. SUBJECTS AND METHODS/METHODS:The study group consisted of 125 patients with symptomatic osteoarthritis of the tibiofemoral joint. For all patients, standing anteroposterior radiographs of the knee were obtained before arthroscopic knee surgery. Each articular surface of the tibiofemoral joint was graded at arthroscopy. Two radiologists retrospectively reviewed the knee radiographs without knowledge of the arthroscopic findings to determine the presence and severity of osteoarthritis of the tibiofemoral joint using the Kellgren-Lawrence, Ahlback, and Brandt grading scales. Correlation coefficients describing the relation between grade of osteoarthritis and severity of articular cartilage degeneration were calculated for each grading scale. RESULTS:The correlation coefficients for the Kellgren-Lawrence, Ahlback, and Brandt grading scales were 0.49, 0.41, and 0.56, respectively. The differences between the correlation coefficients for the Kellgren-Lawrence and Ahlback grading scales and the correlation coefficients for the Brandt and Ahlback grading scales were statistically significant (p < 0.05). Many patients with no radiographic findings of osteoarthritis had significant articular cartilage degeneration within the tibiofemoral joint. CONCLUSION/CONCLUSIONS:The Kellgren-Lawrence and Brandt grading scales were equally effective in defining the presence of and estimating the severity of osteoarthritis of the tibiofemoral joint but had only a moderately strong correlation with the actual degree of articular cartilage degeneration.

The two major imaging modalities used for assessment of soft tissue injuries are ultrasound and MRI. Although ultrasound of the extremities is used only to a limited extent in the United States, it is widely used in many other countries for evaluation of extremity injuries. This article first considers the advantages and disadvantages of MRI and ultrasound. Understanding these differences will help the reader understand the role of ultrasound as compared with MRI in evaluating upper extremity injuries. The uses of ultrasound for evaluating sports medicine injuries in specific regions of the upper extremity are then reviewed. Where the data are available, the reported accuracy of ultrasound is compared with MRI for each type of injury.

MRI is a valuable tool for evaluating the athlete with elbow pain, particularly in those with nonlocalizable pain. MRI also is helpful in sorting out the cause of pain in athletes who may have acute trauma superimposed on tendinopathy or other chronic injuries from repetitive microtrauma. Even in athletes in whom the cause of pain confidently can be diagnosed clinically, MRI can document the injury severity, which can be helpful for estimating recovery time or in preoperative planning. By contributing to an accurate early diagnosis, MRI also can help minimize the time that athletes are away from their sports. The authors describe their approach to the MRI interpretation of elbow injuries in athletes, including osteochondral lesions, epicondylitis, and tears of the medial collateral ligament.

PURPOSE/OBJECTIVE:To determine the feasibility of the vastly undersampled isotropic projection reconstruction steady-state free precession (VIPR-SSFP) sequence for evaluating the articular cartilage of the knee joint. MATERIALS AND METHODS/METHODS:A magnetic resonance (MR) examination of the knee was performed on 33 subjects using a GE 1.5T scanner and a phased-array extremity coil. VIPR-SSFP, proton density-weighted fast spin-echo (PD-FSE), fat-suppressed T2-weighted fast spin-echo (T2-FSE), and three-dimensional fat-suppressed spoiled gradient recall-echo (SPGR) sequences were performed on three asymptomatic volunteers and 10 patients with osteoarthritis of the knee joint. Signal-to-noise efficiency, and contrast-to-noise ratio (CNR) measurements were calculated for all sequences and compared with the use of paired t-tests. The VIPR-SSFP sequence was then performed on 20 consecutive patients who were undergoing a routine MR examination of the knee. RESULTS:The cartilage signal-to-noise efficiency of the VIPR-SSFP sequence was not significantly different from that of the PD-FSE and SPGR sequences. The cartilage signal-to-noise efficiency of the VIPR-SSFP sequence was significantly higher (P < 0.05) than that of the T2-FSE sequence. The VIPR-SSFP sequence produced images with significantly higher (P < 0.05) CNR between cartilage and synovial fluid than the PD-FSE and SPGR sequences, and significantly higher (P < 0.05) CNR between cartilage and subchondral bone than the T2-FSE sequence. The VIPR-SSFP sequence allowed excellent visualization of the articular cartilage of the knee joint in all subjects. All articular cartilage defects identified on the PD-FSE, T2-FSE, and SPGR images were well visualized on the VIPR-SSFP images. CONCLUSION/CONCLUSIONS:VIPR-SSFP images had high cartilage signal-to-noise efficiency and high CNR between cartilage and adjacent synovial fluid and subchondral bone; therefore, the sequence is well suited for evaluating the articular cartilage of the knee joint.

OBJECTIVES/OBJECTIVE:To correlate radiographic findings of osteoarthritis on axial knee radiographs with arthroscopic findings of articular cartilage degeneration within the patellofemoral joint in patients with chronic knee pain. SUBJECTS AND METHODS/METHODS:The study group consisted of 104 patients with osteoarthritis of the patellofemoral joint and 30 patients of similar age with no osteoarthritis of the patellofemoral joint. All patients in the study group had an axial radiograph of the knee performed prior to arthroscopic knee surgery. At the time of arthroscopy, each articular surface of the patellofemoral joint was graded using the Noyes classification system. Two radiologists retrospectively reviewed the knee radiographs to determine the presence of marginal osteophytes, joint-space narrowing, subchondral sclerosis, and subchondral cysts. The sensitivity and specificity of the various radiographic features of osteoarthritis for the detection of articular cartilage degeneration within the patellofemoral joint were determined. RESULTS:The sensitivity of marginal osteophytes, joint-space narrowing, subchondral sclerosis, and subchondral cysts for the detection of articular cartilage degeneration within the patellofemoral joint was 73%, 37%, 4%, and 0% respectively. The specificity of marginal osteophytes, joint-space narrowing, subchondral sclerosis, and subchondral cysts for the detection of articular cartilage degeneration within the patellofemoral joint was 67%, 90%, 100%, and 100% respectively. CONCLUSION/CONCLUSIONS:Marginal osteophytes were the most sensitive radiographic feature for the detection of articular cartilage degeneration within the patellofemoral joint. Joint-space narrowing, subchondral sclerosis, and subchondral cysts were insensitive radiographic features of osteoarthritis, and rarely occurred in the absence of associated osteophyte formation.

PURPOSE/OBJECTIVE:To retrospectively correlate radiographic findings of osteoarthritis of the tibiofemoral joint with arthroscopic findings of articular cartilage degeneration within the tibiofemoral joint in patients with chronic knee pain. MATERIALS AND METHODS/METHODS:The study was performed in compliance with HIPAA regulations. Approval from an institutional review board and a waiver of informed consent were obtained. The study group consisted of 125 patients with osteoarthritis of the tibiofemoral joint (66 men, 59 women; age range, 35-77 years; average age, 52 years) and 25 patients of similar age (14 men, 11 women; age range, 36-69 years; average age, 50 years) with no osteoarthritis of the tibiofemoral joint. All patients underwent standing anteroposterior radiography of the knee prior to arthroscopic knee surgery. Each articular surface of the tibiofemoral joint was graded at arthroscopy. Two radiologists retrospectively reviewed the knee radiographs to determine the presence of marginal osteophytes, joint space narrowing, subchondral sclerosis, and subchondral cysts. The sensitivity and specificity of the radiographic features of osteoarthritis for the detection of articular cartilage degeneration within the medial and lateral compartments of the tibiofemoral joint were determined. RESULTS:The sensitivity of marginal osteophytes, joint space narrowing, subchondral sclerosis, and subchondral cysts for the detection of articular cartilage degeneration was 67%, 46%, 16%, and 10%, respectively, for the medial compartment and 49%, 7%, 6%, and 3%, respectively, for the lateral compartment. The specificity of marginal osteophytes, joint space narrowing, subchondral sclerosis, and subchondral cysts for the detection of articular cartilage degeneration was 73%, 95%, 100%, and 100%, respectively, for the medial compartment and 81%, 100%, 100%, and 100%, respectively, for the lateral compartment. CONCLUSION/CONCLUSIONS:Marginal osteophytes were the most sensitive radiographic feature for the detection of osteoarthritis of the tibiofemoral joint. Joint space narrowing, subchondral sclerosis, and subchondral cysts were less sensitive radiographic features of osteoarthritis and rarely occurred in the absence of associated osteophyte formation.

OBJECTIVE:Few studies have described the MRI findings of osteochondritis dissecans of the capitellum. Our objective was to describe the MRI findings of 10 patients with osteochondritis dissecans of the capitellum and to correlate the imaging findings with surgical findings of stability and instability. CONCLUSION/CONCLUSIONS:The MRI findings of unstable and stable osteochondritis dissecans of the capitellum are similar to the findings described for osteochondritis dissecans of the femoral condyles and talar dome. Unstable osteochondritis dissecans lesions are surrounded by a rim of high signal intensity or a fluid-filled cyst on T2-weighted images. Stable osteochondritis dissecans lesions show no surrounding signal abnormality on T2-weighted images.

Part II of this comprehensive review on magnetic resonance imaging of the elbow discusses the role of magnetic resonance imaging in evaluating patients with abnormalities of the ligaments, tendons, and nerves of the elbow. Magnetic resonance imaging can yield high-quality multiplanar images which are useful in evaluating the soft tissue structures of the elbow. Magnetic resonance imaging can detect tears of the ulnar collateral ligament and lateral collateral ligament of the elbow with high sensitivity and specificity. Magnetic resonance imaging can determine the extent of tendon pathology in patients with medial epicondylitis and lateral epicondylitis. Magnetic resonance imaging can detect tears of the biceps tendon and triceps tendon and can distinguishing between partial and complete tendon rupture. Magnetic resonance imaging is also helpful in evaluating patients with nerve disorders at the elbow.

OBJECTIVE:To compare the MR imaging findings of 13 patients with clinically diagnosed medial epicondylitis with the MR imaging findings of 26 patients of similar age with no clinical evidence of medial epicondylitis. DESIGN AND PATIENTS/METHODS:The study group consisted of 13 patients with clinically diagnosed medial epicondylitis. The control group consisted of 26 patients of similar age with no clinical evidence of medial epicondylitis. The medical records and MR imaging findings of these patients were retrospectively reviewed by two fellowship-trained musculoskeletal radiologists. RESULTS:Eleven of the 13 patients in the study group had thickening and increased signal intensity of the common flexor tendon on both T1-weighted and T2-weighted images. The remaining two patients in the study group had soft tissue edema around a normal-appearing common flexor tendon. Twenty-one of the 26 patients in the control group had a normal-appearing common flexor tendon on MR imaging. Three patients in the control group had a thickened common flexor tendon which was of intermediate signal intensity on T1-weighted images but of uniform low signal intensity on T2-weighted images. Two patients in the control group had a thickened common flexor tendon which was of intermediate signal intensity on both T1-weighted and T2-weighted images. None of the patients in the control group had soft tissue edema around the common flexor tendon. CONCLUSION/CONCLUSIONS:MR imaging findings of patients with clinically diagnosed medial epicondylitis included thickening and increased T1 and T2 signal intensity of the common flexor tendon and soft tissue edema around the common flexor tendon. The presence of intermediate to high T2 signal intensity or high T2 signal intensity within the common flexor tendon and the presence of paratendinous soft tissue edema were the most specific findings of medial epicondylitis on MR imaging.

OBJECTIVE:This study was performed to determine the ability of a routine radiographic examination of the elbow to detect osteochondritis dissecans of the capitellum and associated intra-articular loose bodies. DESIGN AND PATIENTS/METHODS:The study group consisted of 15 patients with osteochondritis dissecans of the capitellum confirmed by surgery or magnetic resonance imaging. Seven of the 15 patients had associated intra-articular loose bodies confirmed by surgery. All 15 patients had anteroposterior and lateral radiographs and magnetic resonance imaging of their symptomatic elbow. Nine of the 15 patients had subsequent elbow surgery. We reviewed the original interpretations of the radiographic examinations of the elbow of all 15 patients to determine whether osteochondritis dissecans of the capitellum and associated intra-articular loose bodies had been identified prospectively. We also reviewed the elbow radiographs of all 15 patients to determine whether osteochondritis dissecans of the capitellum and associated intra-articular loose bodies could be identified retrospectively. RESULTS:Osteochondritis dissecans of the capitellum was detected during the initial interpretations of the radiographic examinations of the elbow in seven of 15 patients. Osteochondritis dissecans of the capitellum was detected during retrospective review of the elbow radiographs in 10 of 15 patients. Intra-articular loose bodies were detected during the initial interpretations of the radiographic examinations of the elbow in three of seven patients. Intra-articular loose bodies were detected during retrospective review of the elbow radiographs in four of seven patients. CONCLUSIONS:A routine radiographic examination of the elbow has limited sensitivity for detecting osteochondritis dissecans of the capitellum and associated intra-articular loose bodies.