Tumors of the elbow and forearm

The trend in the treatment of bone and soft tissue sarcomas of the extremities has been away from radical surgery and toward conservative, limb-sparing surgery, a trend that is present throughout other subdisciplines of surgical oncology. Organ-sparing and limb-sparing surgery has been combined with the use of adjuvants to give equivalent local control and in some cases improved survival. This article summarizes the current staging and treatment of bone and soft tissue tumors of the extremities and discusses some of the features that are unique to the elbow and forearm.     

Ulnar collateral ligament in the growing elbow: MR imaging of normal development and throwing injuries

PURPOSE: To study the magnetic resonance (MR) imaging appearance of the ulnar collateral ligament (UCL) and its insertion into the medial epicondyle. MATERIALS AND METHODS: Sixteen normal and 20 symptomatic elbows were examined with a 1.5-T unit. Normal elbows were imaged with axial T2*-weighted three-dimensional Fourier transform sequences. Symptomatic elbows were imaged with coronal T1-, T2-, and T2*-weighted and/or short-inversion-time inversion-recovery sequences. RESULTS: In normal immature elbows, the ulnar periosteum was seen as an extension of the UCL, and its enthesis had signal intensity characteristics that differed from those of the mature ligament. In symptomatic elbows imaged before epiphyseal fusion, segmentation and subchondral bone resorption of the ossification center were seen with or without a capsular tear. After epiphyseal fusion, a full-thickness or a partial UCL tear at the site of its insertion, with or without subcortical bone resorption, was seen. CONCLUSION: The MR imaging characteristics of the developing elbow differ from those of the mature elbow. MR imaging is useful in assessing UCL damage.     

MR arthrography of the elbow: normal anatomy and diagnostic pitfalls

PURPOSE: Our goal was to determine the normal MR arthrographic appearance of the elbow and to identify the potential diagnostic pitfalls of this technique. METHOD: MRI with intra-articularly administered gadopentetate dimeglumine was performed in seven elbow joints derived from cadavers. Coronal, sagittal, and axial SE T1-weighted images with fat suppression and coronal 3D SPGR images with fat suppression were obtained in each elbow. The elbows were then sectioned. RESULTS: This technique allowed depiction of the cartilaginous surfaces of the elbow joint as well as clear delineation of the inner surface of the collateral ligaments. Potential diagnostic pitfalls included fat pads projecting into the joint, synovial folds, and cartilaginous pseudoerosions. CONCLUSION: MR arthrography allows clear delineation of the intraarticular structures of the elbow. However, diagnostic pitfalls exist that increase the difficulty of interpreting MR arthrographic images.     

Dynamic changes of the spinal canal in patients with cervical spondylosis at flexion and extension using magnetic resonance imaging

Telomerase activity was examined by the telomeric repeat amplification protocol assay, in a total of 37 colorectal adenocarcinomas, including stages A, B and C according to the Astler and Collier classification, and correlated with clinicopathological features. Of 17 stage C lesions, 13 were positive (76.5%; P<0.01), demonstrating a significant correlation with lymph node metastasis. In contrast, only 6 of 20 stage A and B carcinomas were positive (30.0%), this being significantly lower (P < 0.05). Moderately or poorly differentiated subtypes were more predominant in the telomerase-positive than in the telomerase-negative groups (P< 0.05) with greater elevation of mitotic and Ki-67 labeling indices (P < 0.0001). No significant relation was found between telomerase activity and p53 protein accumulation or Bcl-2 protein expression. The good correlation with tumor staging, lymph node metastasis, differentiation, and mitotic and Ki-67 labeling indices suggests that this parameter might have potential application in estimation of prognosis.     

Reducing perineal trauma: implications of flexion and extension of the fetal head during birth

Among the determinant factors in the resistance and susceptibility of Biomphalaria to Schistosoma mansoni, hemocytes play an important role. Aiming at studying S. mansoni/Biomphalaria interactions related to hemocytes, the first step is certainly connected with the standardization of this cell population in uninfected Biomphalaria. In this way, quantification of this cell population in hemolymph, as well as its phagocitary capacity, have been determined for the first time. Furthermore, using susceptible and resistant strains of B. glabrata and B. tenagophila, the hemocytegram and phagocytary capacity of hemocytes after infection with S. mansoni were determined too. Resistant and susceptible strains of B. glabrata (BA and BH, respectively), as well as resistant and susceptible strains of B. tenagophila (TAIM and CF, respectively) were infected with 10 miracidia of the LE and SJ strains of S. mansoni, respectively. These infected snails and respective uninfected controls were assessed in relation to the number of circulating hemocytes and alteration in the phagocytary capacity, by using Zymozan and MTT. Reading was taken by means of a spectrophotometer at 5 hours and 1, 2, 5, 10, 20 and 30 days after infection. The results showed a decrease in population of the circulating phagocytary cells, 5 hours after infection. One day post-infection, the circulating cells of the susceptible snails showed an increased metabolic activity, but the same event could not be observed in the resistant strains. In the subsequent observation periods, significant differences among the strains studied could not be observed until the end of the experiment.     

The significance of the three volar spaces in forearm compartment syndrome: a clinical and cadaveric correlation

The goal of this study was to assess the importance of the 3 volar spaces in forearm compartment syndrome in a prospective manner. A cadaveric model was developed to correlate with our clinical experience. All but 1 of 21 volar compartments (superficial volar, deep volar, and pronator quadratus spaces) in 7 patients in our clinical series decompressed adequately after release of the superficial volar fascia. One patient needed further release of the pronator quadratus compartment; he had suffered a combined crush and vascular injury. All volar compartments in our cadaveric model decompressed with superficial fasciotomy. Prefasciotomy and postfasciotomy pressures should be obtained from all 3 compartments of the volar forearm. Superficial fasciotomy usually adequately decompresses the entire volar forearm; however, in the event that deep compartment pressures remain high after superficial fasciotomy, release of the affected space is indicated.     

Computer-assisted instruction: MR imaging of the knee

Computer-assisted education offers a unique method of learning that is complementary to conventional learning techniques. The regional anatomy of musculoskeletal magnetic resonance (MR) imaging lends itself well to discrete learning modules on the computer. This article describes a computer-assisted educational program for MR imaging of the knee. The program is divided into four sections: MR imaging physics, anatomy, pathology, and a quiz. The program has cross-references between the sections that allow comparison of normal versus pathologic findings, review of specified pathologic entities, and self-testing of comprehension. The student can progress through the program in a linear or nonlinear fashion at his or her own pace. All images in the program were digitally acquired with an MR imager and transferred directly to the computer used to develop the program. The program is available throughout the radiology department on a local area network and in the medical school library on stand-alone units. The program is currently being used at a medical school as a supplement to the recently implemented problem-based learning curriculum and for resident education.     

Traumatic forearm amputation with avulsions of the ulnar and median nerves from the brachial plexus

A case of a traumatic forearm amputation and associated complete avulsions of the ulnar and median nerves from the brachial plexus due to a crush-traction injury of the distal part of the right forearm is reported. The patient also suffered a traumatic head injury. The injury of the upper limb and the general condition of the patient were so serious that an amputation at the 1/3 middle part of the forearm had to be performed.     

MR arthrography of the shoulder: rethinking traditional imaging procedures to meet the technical requirements of MR imaging guidance

Increased serum levels of mucin-associated antigen have been previously demonstrated in patients with cystic fibrosis (CF) and interstitial pneumonia, and in lung-transplant recipients. The present study assessed the serum airway mucin levels in patients with acute respiratory distress syndrome (ARDS). An enzyme-linked immunosorbent assay (ELISA) method with a human-airway-mucin-specific monoclonal antibody (17Q2) was used to measure serum mucin levels in normal subjects, chronic smokers, patients with chronic bronchitis and other pulmonary diseases, patients with acute cardiogenic lung edema, and patients with ARDS. The serum mucin levels measured 9.9 +/- 0.8 ng/ml (mean +/- SEM, n = 59) in normal subjects, 12.7 +/- 1.6 ng/ml (n = 29) in chronic smokers, 21.8 +/- 1.9 ng/ml (n = 28) in patients with chronic bronchitis and other pulmonary diseases, 9.0 +/- 3.1 ng/ml (n = 5) in patients with acute cardiogenic lung edema. The serum mucin level was 53.8 +/- 6.6 ng/ml (n = 13) in patients with ARDS (p < 0.05, as compared with the four other groups). Serial measurements of serum mucin levels were obtained in patients with ARDS. Statistical analysis showed an inverse correlation of serial measurements of serum mucin with static respiratory-system compliance (p = 0.021), an inverse correlation of sequential serum mucin levels and log(Pa(O2)/Fl(O2)) (p = 0.016), and a positive correlation of sequential serum mucin levels and lung injury score (LIS) (p = 0.019). Gel-filtration analysis showed that mucin-associated antigens in ARDS sera were polydispersed and smaller than the antigens in normal sera. This study indicates that an increasing amount of degraded mucin occurs in patients with ARDS.     

A twin study examining the effect of parity on the prevalence of psychiatric disorder

The study compares the prevalence of current and lifetime psychiatric illness in twin pairs where one twin is more parous than the other. The main finding was that parity did not affect the prevalence of psychiatric disorder. This adds confirmation to the study of Bebbington et al. (1991) that high prevalence rates in women with children is due to an effect of marriage rather than an effect of parity. There was a diagnostic difference between the twins with the less parous twin having significantly more cases of Research Diagnostic Criteria (RDC; Spitzer et al., 1978) major and minor depression and the more parous twin more cases of generalised anxiety disorder. The life events and difficulties in the previous 12 months were also established in the whole group and events and difficulties over the whole of the subjects life for the first 20 pairs. The total number of events in the previous 12 months was significantly higher in the more parous twin of the pair, these were child-related events and not associated with an increased likelihood of current psychiatric illness. There were no differences in the number of events and difficulties during the lifetime between the first 20 twin pairs.     

The nerves of two''s, three''s and four''s: a simple method for learning the neuroanatomy of the forearm

Mukali (Aningeria robusta) is an exotic wood from the Sapotaceae family. We describe the case of a 31-year-old woman who developed bronchial asthma and contact urticaria after occupational exposure to mukali. A positive immediate response was observed in the skin prick test, bronchial challenge and the rubbing test performed with a mukali wood extract. We suggest that an IgE-mediated immunological mechanism could explain these findings. Our case report identifies another wood dust capable of inducing occupational asthma.     

Measurement of regional aortic compliance by MR imaging: a study of reproducibility

The reproducibility of MR imaging for the measurement of aortic compliance was studied in 47 healthy volunteers. Long and short term reproducibility and intraobserver variability were tested. The method was modified to improve image quality and short term reproducibility and intraobserver variability retested. For comparison, spin echo imaging was compared with cine gradient echo imaging. Initial long term reproducibility showed a mean difference (+/-SE) of 3% (+/- 7%) with 95% confidence interval (CI) for limits of agreement of +/- 69%. Short term reproducibility (7% +/- 6%, 95% CI +/- 46%) and intraobserver variability (1% +/- 2%, 95% CI +/- 31%) were better. After modification of the technique and optimization of image quality, both short term reproducibility and intraobserver variability improved (0% +/- 3%, 95% CI +/- 17% and 5% +/- 2%, 95% CI +/- 16% respectively). Aortic compliance can be measured using spin echo MR imaging with good reproducibility provided care is taken to obtain good quality images with high spatial resolution.     

Exacerbated pain in cervical radiculopathy at axial rotation, flexion, extension, and coupled motions of the cervical spine: evaluation by kinematic magnetic resonance imaging

RATIONALE AND OBJECTIVES: The authors evaluate the functional changes in patients with cervical radiculopathy and increasing symptoms after provocative maneuvers at flexion, extension, axial rotation, and coupled motions of the cervical spine. METHODS: Twenty-one patients with cervical disc herniation (n = 17) or cervical spondylosis (n = 4) in whom symptoms were elicited at flexion, extension, axial rotation, and coupled motions of the cervical spine were studied. The patients were examined inside a positioning device by using a circular surface coil for signal reception. At neutral position (0 degrees) and at provocative positions sagittal T2-weighted turbo spin-echo, axial T2-weighted two-dimensional flash sequence, sagittal three-dimensional (3D) fast imaging with steady state precision sequence and coronal 3D double-echo-in-the-steady-state sequences were obtained. The 3D sequences were reformatted in the axial and oblique coronal planes perpendicular to the exiting nerve roots. The images were evaluated for the size of disc herniations, the foraminal size and cervical cord rotation or displacement at provocative position compared with neutral position (0 degrees). RESULTS: Compared with neutral position (0 degrees), change in size of disc herniation was not found in any (0%) of the provocative positions. In five (24%) patients cervical cord rotation or displacement was noted at axial rotation. The foraminal size increased at flexion, axial rotation to the opposite side of pain and flexion combined with axial rotation to the opposite side of the pain. The foraminal size decreased at extension combined with axial rotation to the side of the pain. A decrease or no change in foraminal size was observed at either extension or axial rotation to the side of the pain. CONCLUSIONS: In patients with cervical disc herniation or cervical spondylosis, exacerbated pain at defined provocative maneuvers is related more to changes in the foraminal size and to nerve root motion with, in some cases, cervical cord rotation or displacement than to changes in the size of herniated discs.     

The effect of a flexion contracture of the elbow on the ability to transfer in patients who have quadriplegia at the sixth cervical level

We studied six patients (twelve upper extremities) who had quadriplegia at the sixth cervical level. Our purpose was to evaluate how the loss of terminal extension of the elbow adversely affected the ability of the patient to perform transfers with a sliding board and so-called depression raises (lifting of the body with use of the extended upper extremities to reduce the pressure on the ischial tuberosities). Function of the triceps muscle was considered to be absent in eight upper extremities and present in four. A flexion contracture of the elbow was simulated with use of a specially fabricated, hinged elbow brace. Terminal extension was progressively limited, in 5-degree increments, until the patient was no longer able to perform the transfer or the depression raise. The mean flexion contracture at which the patient could not perform the transfer or the depression raise was approximately 25 degrees when function of the triceps was absent and approximately 50 degrees when function of the triceps was intact. The results of this study emphasize the importance of maintaining the full range of motion of the elbow in a patient who has high-level quadriplegia. In a patient who has quadriplegia at the sixth cervical level who otherwise would be independent with regard to transfer skills and mobility in bed, a flexion contracture of the elbow of approximately 25 degrees or more can result in the loss of a functional level and render the patient as dependent as one who has quadriplegia at the fifth cervical level.     

Diseases of the intracranial meninges: MR imaging features

Although the meninges are often thought of simplistically as a connective tissue sac that contains the CSF and the contents of the CNS, they are far more complex. Anatomically, they comprise several layers. Pathologically, numerous disease processes may affect the meninges; different processes may even involve different areas of the meninges. These factors all influence the MR imaging characteristics of meningeal lesions. This review briefly discusses the anatomy of the meninges, the MR imaging technique when meningeal disease is suspected, and the appearance of the normal meninges. It then focuses on tumors, infections, cysts, and other lesions that primarily involve the meninges, excluding lesions that secondarily involve the meninges.     

MR imaging technique for the diagnosis of pituitary iron overload in patients with transfusion-dependent beta-thalassemia major

To identify the optimal MR imaging technique for diagnosing pituitary iron overload, we compared spin-echo and gradient-echo MR imaging with measurements of pituitary T2 relaxation times in 30 patients with secondary hemochromatosis due to transfusion-dependent beta-thalassemia major and in 10 healthy volunteers. We found that the optimal MR imaging technique to evaluate pituitary iron overload is the gradient-echo T2*-weighted technique, as it best demonstrated signal reduction in the anterior lobe of the pituitary gland.     

Pancreatic adenocarcinoma: combination of MR imaging, MR angiography and MR cholangiopancreatography for the diagnosis and assessment of resectability

BACKGROUND: Enteropancreatic malignancy is an important cause of morbidity and mortality associated with multiple endocrine neoplasia type 1 (MEN 1). However, the risk factors and mechanisms of the tumorigenesis of this malignancy are poorly understood. METHODS: The authors conducted a retrospective study of factors associated with the development of malignant enteropancreatic tumor in 69 patients with MEN 1 belonging to a single family. RESULTS: Metastatic enteropancreatic tumor and gastrinoma were identified in 20% and 36% of patients, respectively. Compared with MEN 1 patients who did not have an immediate family history of enteropancreatic malignancy, MEN 1 patients with a first-degree relative affected by enteropancreatic malignancy had an increased risk of developing disseminated tumor (odds ratio, 3.7; P < 0.05). In addition, hypergastrinemia and advanced age were both associated with a significant increase in the risk of enteropancreatic malignancy. Elevated serum glycoprotein alpha subunit levels were associated with enterochromaffin-like cell hyperplasia, gastric carcinoid formation, and disseminated enteropancreatic tumor in hypergastrinemic patients (P < 0.05). CONCLUSIONS: Disease modifier factors act in concert with the MEN 1 gene to modulate the development of enteropancreatic neoplasia. It is possible to identify MEN 1 patients at high risk for developing aggressive enteropancreatic tumors. Heritable disease modifier factor(s) affecting enteropancreatic malignancy appear to reside at loci distinct from that of the MEN 1 gene.     

MR imaging of the adrenal gland: radiologic-pathologic correlation

Complex physiologic and neoplastic processes affect the adrenal glands. An appreciation of the gross pathologic and histologic correlates of disease aids in understanding the mechanisms by which diagnostic imaging helps characterize adrenal masses. Computed tomographic (CT) densitometry and chemical shift magnetic resonance (MR) imaging would seem to be the most reliable tools in determining whether a given adrenal mass is specifically an adenoma. Such a determination is made on the basis of the presence of substantial amounts of intracytoplasmic lipid. Thus, although a homogeneous mass with a CT attenuation of less than 10 HU or a decrease in signal intensity at opposed-phase MR imaging is diagnostic for adenoma, lesions that do not have these features are indeterminate and may necessitate biopsy. Adrenal myelolipoma also has a distinctive imaging appearance that reflects the presence of macroscopic fat deposits. Diagnosis of adenoma or adrenal myelolipoma is very helpful in the assessment and treatment of asymptomatic patients with adrenal masses and may make biopsy unnecessary. In patients with clinical or biochemical evidence of adrenal disease, MR imaging helps confirm the presence of a mass and allows localization and further characterization of the lesion.