Curtis W. Hayes

Magnetic resonance-detected subchondral bone marrow and cartilage defect characteristics associated with pain and X-ray-defined knee osteoarthritis

OBJECTIVE To assess whether the presence of subchondral bone marrow abnormalities (bone marrow edema (BME)) and cartilage defects, determined by magnetic resonance imaging (MRI), would explain the difference between painful osteoarthritis of the knee (OAK) compared with painless OAK or pain without OAK. METHOD Four groups of women (30 per group), aged 35-55 years, were recruited from the southeast Michigan Osteoarthritis cohort (group 1: painful OAK; group 2: painless OAK; group 3: knee pain without OAK; and group 4: no OAK or knee pain). OAK was defined by a Kellgren-Lawrence score of 2 or greater, while pain was based on self-report. BME and cartilage defects were identified from MRI. RESULTS BME lesions were identified in 56% of all knees. BME lesions were four times (95% CI=1.7, 8.7) more likely to occur in the painless OAK group as compared with the group with pain, but no OAK. BME lesions >1cm were more frequent (OR=5.0; 95% CI=1.4, 10.5) in the painful OAK group than all other groups. While the frequency of BME lesions was similar in the painless OAK and painful OAK groups, there were more lesions, >1cm, in the painful OAK group. About 75% of all knees had evidence of some cartilage defect, of which 35% were full-thickness defects. Full-thickness cartilage defects occurred frequently in painful OAK. One-third of knees with full-thickness defects and 47% of knees with cartilage defects involving bone had BME >1cm. Women with radiographic OA, full-thickness articular cartilage defects, and adjacent subchondral cortical bone defects were significantly more likely to have painful OAK than other groups (OR=3.2; 95% CI=1.3, 7.6). CONCLUSION The finding on MRI of subchondral BME cannot satisfactorily explain the presence or absence of knee pain. However, women with BME and full-thickness articular cartilage defects accompanied by adjacent subchondral cortical bone defects were significantly more likely to have painful OAK than painless OAK.

A 2-year randomised, double-blind, placebo-controlled, multicentre study of oral selective iNOS inhibitor, cindunistat (SD-6010), in patients with symptomatic osteoarthritis of the knee

Objective To determine if inhibition of inducible nitric oxide synthase (iNOS) with cindunistat hydrochloride maleate slows progression of osteoarthritis (OA) Methods This 2-year, multinational, double-blind, placebo-controlled trial enrolled patients with symptomatic knee OA (Kellgren and Lawrence Grade (KLG) 2 or 3). Standard OA therapies were permitted throughout. Patients were randomly assigned to cindunistat (50 or 200 mg/day) or placebo. Randomisation was stratified by KLG. Radiographs to assess joint space narrowing (JSN) were acquired using the modified Lyon-schuss protocol at baseline, week 48 and 96. Results Of 1457 patients (50 mg/day, n=485; 200 mg/day, n=486; placebo, n=486), 1048 (71.9%) completed the study. Patients were predominantly women; 56% had KLG3. The primary analysis did not demonstrate superiority of cindunistat versus placebo for rate of change in JSN. In KLG2 patients, JSN after 48 weeks was lower with cindunistat 50 mg/day versus placebo (p=0.032). Least-squares mean±SE JSN with cindunistat 50 mg/day ( −0.048±0.028 mm) and 200 mg/day (−0.062±0.028 mm) were 59.9% (95% CI 6.8% to 106.9%) and 48.7% (95% CI -8.4% to 93.9%) of placebo, improvement was not maintained at 96 weeks. No improvement was observed for KLG3 patients at either time-point. Cindunistat did not improve joint pain or function, but was generally well tolerated. Conclusions Cindunistat (50 or 200 mg/day) did not slow the rate of JSN versus placebo. After 48-weeks, KLG2 patients showed less JSN; however, the improvement was not sustained at 96-weeks. iNOS inhibition did not slow OA progression in KLG3 patients. Clinical trial listing NCT00565812

Use of a Validated Algorithm to Judge the Appropriateness of Total Knee Arthroplasty in the United States: A Multicenter Longitudinal Cohort Study

In previous studies conducted outside the US, ∼20% of total knee arthroplasty (TKA) surgeries were judged to be inappropriate. The present study was undertaken to determine the prevalence rates of TKA surgeries classified as appropriate, inconclusive, and inappropriate in a knee osteoarthritis population in the US.

Dry taps and what to do about them: A pictorial essay on failed arthrocentesis of the knee

PURPOSE To determine and illustrate the causes of unproductive arthrocentesis of the knee. PATIENTS AND METHODS Consecutive patients were studied who had inflammatory (rheumatoid or psoriatic) arthritis affecting the knees and experienced unproductive arthrocentesis during a randomized, controlled trial. Magnetic resonance imaging (MRI) was used, supplemented first by intravenous gadolinium contrast and subsequently by manual mixing of the diffused contrast to outline the furthest possible penetration of contrast within the joint cavity. RESULTS In 4 out of 5 patients studied, failed arthrocentesis was due to combinations of inspirated joint fluid too viscous to be withdrawn or to mix with contrast, adipose tissue, and lipoma arborescens (thickened synovium with fat replacement). One MRI exam was normal. More free synovial fluid was imaged on the lateral side. CONCLUSIONS Failure to aspirate synovial fluid from the knee is explicable to anatomic terms; in particular, fluid viscosity and lipoma arborescens play a role in chronic effusions. Although surface anatomic landmarks for knee arthrocentesis may be more visible medially, the lateral approach is more likely to yield fluid for synovial analysis in difficult cases. Internal medicine trainees should be taught the lateral approach.

Sonographic Target Sign in Neurofibromas

Neurofibromas are the most common tumors of the peripheral nerves. They may be solitary lesions, multiple localized lesions, or large plexiform masses often associated with neurofibromatosis. Relatively few reports discuss the sonographic features of PNST, specifically neurofibromas.1–7 The typical sonographic description is that of a well defined, homogeneous hypoechoic lesion, which can show posterior acoustic enhancement mimicking a cystic lesion.1,3,4 We present a case of neurofibromatosis in a 19 year old man, which was initially diagnosed by ultrasonography. We describe the ultrasonographic findings that we believe correspond to the so-called target sign on T2-weighted MR imaging examinations. The appearance on T2-weighted MR images is reported as increased signal intensity peripherally and decreased signal intensity centrally.8–10 A target sign appearance was seen sonographically in numerous lesions, demonstrating a hyperechoic central region and a hypoechoic periphery.

Calcific tendinitis of the gluteus medius tendon with bone marrow edema mimicking metastatic disease

Abstract. A case of calcific tendinitis of the gluteus medius is presented. This report describes a patient with a history of breast cancer who had the combination of amorphous calcifications in the gluteus medius tendon and the MR finding of conspicuous bone marrow edema in the adjacent greater trochanter, prompting concern for metastatic disease. We present images from radiography, bone scanning, CT, and MR imaging. The unusual combination of findings in these studies should be considered conclusive for calcific tendinitis, and should not be confused with malignancy.

Sonography of Partial-Thickness Quadriceps Tendon Tears With Surgical Correlation

Objective. With the use of surgical findings as the reference standard, the purpose of this study was to describe the sonographic findings of partial‐thickness and complete tears of the quadriceps tendon and to determine whether sonography can potentially aid diagnosis. Methods. Three hundred eighty‐nine consecutive sonographic reports (January 1996 to April 2001) of the knee/quadriceps tendon were reviewed retrospectively and assessed for subsequent surgery on the quadriceps tendon. Seven cases were thus identified. Findings at surgery (complete versus partial tears) were compared with the original sonography reports. Results. All 4 partial tears and 1 of 2 complete tears were diagnosed correctly on the basis of sonography. One complete tear was described as a partial tear on the basis of sonography. In a seventh case, complete disruption of the extensor mechanism with osseous avulsion of the superior pole of the patella was identified correctly. Dynamic scanning was essential in diagnosing a partial quadriceps tendon tear in 1 case. Conclusions. Sonography, including the use of dynamic evaluation, was helpful in the diagnosis of partial‐thickness tears of the quadriceps tendon and may aid in differentiation of such cases from complete quadriceps tendon tears, particularly in the acute setting. The presence of scar tissue in the setting of chronic injury may represent a potential pitfall in the assessment of partial versus complete quadriceps tears. Further study is needed to define the accuracy of sonography for detecting quadriceps tendon tears.

Sonographic evaluation of the median nerve at the wrist

Received March 23, 2001, from the Department of Radiology, University of Michigan Hospitals, Ann Arbor, Michigan. Revision requested April 30, 2001. Revised manuscript accepted for publication June 4, 2001. Address correspondence and reprint requests to David A. Jamadar, MB, BS, Radiology, TC 2910, University of Michigan Hospitals, 1500 E Medical Center Dr, Ann Arbor, MI 48109-0326. onography is now used to evaluate many disorders of the musculoskeletal system.1 One such example is evaluation of the median nerve in carpal tunnel syndrome.2 Sonographic findings such as median nerve enlargement immediately proximal to the carpal tunnel and bowing of the flexor retinaculum have been described in these patients.2 A correct diagnosis relies on accurate identification of the median nerve and an understanding of the osseous landmarks delineating the carpal tunnel. The presence of multiple closely approximated linear echogenic structures at the volar wrist makes identification of the median nerve difficult; differentiation from the palmaris longus tendon and other tendons may occasionally prove challenging. We present a technique that allows reliable identification of the median nerve at several locations in the distal forearm and wrist by using the real-time capability of sonography. Median nerve pathologic characteristics are also described.

Dynamic Magnetic Resonance Imaging of the Temporomandibular Joint Using FLASH Sequences

Magnetic resonance imaging (MRI) is a suitable modality for the visualization of the temporomandibular joint (TMJ) in both normal and pathologic conditions. Until recently, MRI had been unable to provide diagnostic dynamic images of the TMJ during opening. A series of 30 TMJ MRI examinations of 17 symptomatic patients and two normal volunteers (15 to 43 years old; 14 men and five women) was performed. Fast low angle shot (FLASH) sequences were used to provide a series of dynamic images of the TMJ in various phases of opening. In 30% of the joint examined, FLASH sequences contributed clinically significant information not available with standard T1-weighted sequences. These results suggest that FLASH images are particularly useful in distinguishing normal disc variants from pathologic conditions in which the disc is displaced anteriorly to a mild extent. The short imaging time of FLASH sequences decreases motion artifact in patients who have difficulty remaining still during the examination.

Classification of Common Acetabular Fractures: Radiographic and CT Appearances

OBJECTIVE Accurate characterization of acetabular fractures can be difficult because of the complex acetabular anatomy and the many fracture patterns. In this article, the five most common acetabular fractures are reviewed: both-column, T-shaped, transverse, transverse with posterior wall, and isolated posterior wall. Fracture patterns on radiography are correlated with CT, including multiplanar reconstruction and 3D surface rendering. CONCLUSION In the evaluation of the five most common acetabular fractures, assessment of the obturator ring, followed by the iliopectineal and ilioischial lines and iliac wing, for fracture allows accurate classification. CT is helpful in understanding the various fracture patterns.