Objectives
To describe a type of meniscus flap tear resembling a bucket-handle tear, named a “hemi-bucket-handle” tear; to compare its imaging features with those of a typical bucket-handle tear; and ...to discuss the potential therapeutic implications of distinguishing these two types of tears.
Materials and methods
Five knee MR examinations were encountered with a type of meniscus tear consisting of a flap of tissue from the undersurface of the meniscus displaced toward the intercondylar notch. A retrospective analysis of 100 MR examinations prospectively interpreted as having bucket-handle type tears yielded 10 additional cases with this type of tear. Cases of hemi-bucket-handle tears were reviewed for tear location and orientation, appearance of the superior articular surface of the meniscus, presence and location of displaced meniscal tissue, and presence of several classic signs of bucket-handle tears.
Results
A total of 15/15 tears involved the medial meniscus, had tissue displaced toward the notch, and were mainly horizontal in orientation. The superior surface was intact in 11/15 (73.3%). In 1/15 (6.7%) there was an absent-bow-tie sign; 6/15 (40%) had a double-PCL sign; 14/15 (93.3%) had a double-anterior horn sign.
Conclusion
We describe a type of undersurface flap tear, named a hemi-bucket-handle tear, which resembles a bucket-handle tear. Surgeons at our institution feel this tear would likely not heal if repaired given its predominantly horizontal orientation, and additionally speculate the tear could be overlooked at arthroscopy. Thus, we feel it is important to distinguish this type of tear from the typical bucket-handle tear.
Sports medicine is one of the most rapidly growing subspecialties in orthopedics. Magnetic resonance (MR) imaging in sports medicine includes depiction of normal anatomy and pathologic conditions in ...almost every joint in the body, but the MR examinations most frequently requested are of the knee and shoulder. The reported high accuracy of MR imaging in the knee has resulted in MR imaging being preferred to diagnostic arthroscopy by most leading orthopedic surgeons. MR imaging is particularly helpful for sports medicine surgeons in evaluating menisci to determine if they are repairable, in posterolateral corner syndrome, and in evaluating the hyaline articular cartilage. In evaluating the shoulder, MR arthrography is becoming the preoperative imaging procedure of choice for many sports medicine surgeons. Shoulder MR imaging is particularly important in helping identify abnormalities that may mimic rotator cuff or labral abnormalities at clinical examination, thus preventing unnecessary surgery in some patients. These abnormalities include Parsonage-Turner syndrome and quadrilateral space syndrome, each of which has a distinctive MR imaging appearance. As the field of sports medicine expands, radiologists will continue to see increased requests for MR imaging, because sports medicine and high-quality imaging are inextricably linked.
To compare the sensitivities of contiguous axial (CA) images and disc space-targeted angled axial (DSTAA) images of the lumbar spine for: (1) the detection of spondylolysis defects, and (2) the ...identification of disc material which has migrated away from the parent disc.
Prospective imaging of the lumbar spine was performed over a 22-month period in 103 patients. Imaging protocols included spin-echo T1- and fast spin-echo (FSE) T2-weighted images in the sagittal and axial planes. For each patient, axial images were obtained both contiguously throughout the lumbar spine and as angled images, targeted at the region of the disc space only. Two separate data sets were compiled: one that included contiguous axial images (CA data set) and another that included targeted angled images through the disc spaces only (DSTAA data set). Identical sagittal images were included with both sets. A single radiologist independently interpreted the two data sets for a given patient following an intervening time lapse. The radiologist was blinded to the initial interpretation. Results from the two independent interpretations were then compared.
Spondylolysis defects were identified at 15 different levels in 14 patients (14%) using the contiguous axial imaging protocol compared with 8 (7%) identified using the disc space targeted angled axial imaging protocol (P = 0.12). Migrated disc material was identified in 12 patients (12%) using the CA protocol compared with 3 patients (3%) identified with the DSTAA protocol (P = 0.016).
MR imaging of the lumbar spine using contiguous axial data obtained through both the level of the disc and vertebral body demonstrates migrated disc material and spondylolysis defects better than did disc space-targeted angled data.
This study compared shoulder radiographs of patients with a documented rotator cuff tear with those of asymptomatic age-matched controls. Radiographs of 40 subjects with documented rotator cuff tears ...were evaluated along with similar films of 84 asymptomatic age-matched controls. Three radiographs were taken of each shoulder: (1) acromioclavicular joint view, (2) anterior-posterior view with 30° of external rotation, and (3) supraspinatus outlet view. Two fellowship-trained radiologists interpreted 14 radiographic areas in a blinded fashion. Inspection of the greater tuberosity showed large positive abnormal ratings for sclerosis, osteophytes, subchondral cysts, and osteolysis. No association was noted between acromial morphology and rotator cuff tears. These results indicate that shoulder radiographs of subjects with a documented rotator cuff tear have greater tuberosity radiographic abnormalities that are not noted in asymptomatic subjects without a rotator cuff tear. No relationship was found between tear length and any of the degenerative conditions. (J Shoulder Elbow Surg 2003;12:122-7)
MR Imaging of Infrapatellar Plica Injury Cothran, R. Lee; McGuire, Philip M; Helms, Clyde A ...
American journal of roentgenology (1976),
05/2003, Letnik:
180, Številka:
5
Journal Article
Recenzirano
Injury to the infrapatellar plica (ligamentum mucosum) has not been previously described in the radiology literature to our knowledge. This article shows the MR imaging appearance of injury to the ...infrapatellar plica.
Injury to the infrapatellar plica is uncommon but should be considered as a potential source of knee pain, especially if no other evidence indicates internal derangement. MR imaging can reveal a typical appearance for infrapatellar plica injury.
We describe the MR imaging features of medial meniscus flap tears in which the fragment becomes located inferomedial to the tibial plateau and deep in relation to the medial collateral ligament.
...Inferior flap tears of the medial meniscus can be inconspicuous and overlooked by both radiologists and orthopedic surgeons. Inferiorly displaced meniscal fragments may escape detection during arthroscopic surgery unless the fragment is sought with a probing hook. Recognition of this meniscal abnormality on MR imaging is important for preoperative planning.
Our objective was to prove through cadaveric correlation that a frequently seen focus of MRI signal in the calcaneus is benign.
A characteristic focus of signal (increased T2, decreased T1) in the ...calcaneus near the attachment of the cervical and interosseous ligaments is a common, benign finding frequently seen on MRI of the foot and ankle.
Patients with solitary plasmacytoma in the spine frequently require a biopsy for diagnosis of their condition. We report an appearance of plasmacytoma in the spine, which is sufficiently ...pathognomonic to obviate biopsy.
Identification of a "mini brain" in an expansile lesion in the spine is characteristic of plasmacytoma. It is important that radiologists note this characteristic because biopsy can be avoided in patients with this appearance. Although biopsy might still be required at many institutions, at our institution, surgeons find this appearance sufficiently pathognomonic to bypass biopsy and start treatment.
To demonstrate with radiographic imaging the association between pubic stress injury and sacroiliac abnormalities in athletes.
Eleven athletes (9 men and 2 women), comprising seven male long-distance ...runners, one male soccer player, one male and two female basketball players, were imaged with plain films for complaints of pubic symphysis pain, sciatica, groin pain, or a combination of these complaints. In addition to the plain films, four patients were imaged with CT, two patients had MR imaging, and a bone scan was performed in three patients. Anteroposterior plain films of the pelvis of 20 patients without back pain or pubic pain were evaluated for comparison as a control group (ages 18-72 years, average 49 years; 11 women and 9 men).
All athletes showed plain film evidence of either sclerosis, erosions or offset at the pubic symphysis. Four had avulsion of cortical bone at the site of insertion of the gracilis tendon. Four patients demonstrated sacroiliac joint abnormalities on plain films consisting of sclerosis, erosions and osteophytes, and in one of these athletes, bilateral sacroiliac changes are present. Two patients with normal sacroiliac joints on plain films had a bone scan showing increased radionuclide uptake bilaterally at the sacroiliac joints. One patient with both plain film and CT evidence of sacroiliac abnormalities had an MR examination showing abnormal signal at both sacroiliac joints and at the pubic symphysis. A sacral stress fracture was found on CT in one patient with complaints of sciatica. In the control group, six patients, all over the age of 55 years, had mild sclerosis of the symphysis, but no plain film evidence of sacroiliac abnormalities.
We have found a group of athletes in whom stress injuries to the pubic symphysis are associated with changes in the sacroiliac joint as demonstrated by degenerative changes or in the sacrum as manifested as a sacral stress fracture. These findings are probably due to abnormal stresses across the pelvic ring structure that lead to a second abnormality in the pelvic ring. The abnormality in the sacrum is not always well seen with conventional imaging. Recognition of the association of stress injury of the symphysis with back pain is important in that it can help avoid inappropriate studies and diagnostic confusion.
