Comparison of pain perceived when using pneumatic or silicone ring tourniquets for local anaesthetic procedures in the upper limb.

The aim of this study was to evaluate the level of pain felt when silicone ring and pneumatic tourniquets were applied to the upper arm and to determine which was more suitable for use in local anaesthetic procedures. Pain was measured using a visual analogue score pain scale on application and at 1, 5, and 10 minutes in 30 volunteers. Volunteers experienced significantly more pain on application and at 1 and 5 minutes with the silicone ring tourniquet. This difference in pain was most marked on application. Two volunteers could not tolerate application of the silicone ring tourniquet. We conclude that the silicone ring tourniquet would not be suitable for local anaesthetic procedures in the upper limb due to the severe pain experienced on application, which may reduce the patients' confidence and adversely affect their experience of the procedure. The pneumatic tourniquet is more suitable for local procedures.

Metal and oxalate contamination in a suburban watershed in the greater Toronto area: the benefits of combining acid leach and selective extraction procedures.

Environmentally available concentrations of Fe, Mn, Zn, Cu, Pb, Cr and Ni in soils and sediments from a small suburban catchment, obtained using an acid leach procedure, are compared to the Ontario Ministry of the Environment lowest effect level (LEL) and severe effect levels (SEL) and to Provincial sediment quality guidelines (PSQG's). These data are then compared to the bioavailability, potential bioavailability and non-bioavailability of the same metals, plus oxalate concentration, identified using a selective extraction procedure. This combination of techniques enhanced analytical interpretation with respect to metal mobility and potential metal contamination. Selective extraction highlighted the presence of oxalate as a potential contaminant, especially in poorly drained valley floor deposits (33,633 mg kg(-1) and 26,284 mg kg(-1)) and lakeshore sediments (27,095 mg kg(-1) and 13,729 mg kg(-1)). These levels are considerably in excess of those previously documented in a similar study from Rio de Janeiro, where contamination of urban sediment by sewage is a recognised environmental problem, and could possibly be used both as an indicator of similar contamination and the identification of those areas that warrant further investigation.

The cellular functions of clathrin.

Membranes and proteins are moved around the cell in small vesicles. A protein coat aids the budding of such vesicles from donor membranes. The major type of coat used by the cell is composed of clathrin, a three-legged protein that can form lattice-like coats on membranes destined for trafficking. In this review, I outline what we know about clathrin and discuss some recent advances in understanding the basic biology of this fascinating molecule, which include building a molecular model of a clathrin lattice and discovery of a new function for clathrin that occurs during mitosis.

Behavioural analysis and susceptibility to CNS injury of four inbred strains of mice.

Interpretation of data from gene targeting studies can be confounded by the inherent traits of the background inbred strains used in the generation of transgenic and null mutant mice. We have therefore compared the behaviour and response to CNS injury of four inbred strains commonly used in molecular genetic studies to produce models of neurological disease. Adult, male 129/Ola, BALB/c, C57BL/6 and FVB/N mice (2-4 months) were initially subjected to behavioural tests that comprised a neurological examination, determination of motor function and cognitive testing in the Morris water maze. Also the response to CNS injury following an acute kainic acid (KA) challenge (30 mg kg-1, i.p.) was determined. The 129/Ola and BALB/c strains showed significant motor deficits when compared with the C57BL/6 and FVB/N strains. In contrast, only the FVB/N strain showed evidence of apparent cognitive impairments in the water maze as evidenced by increased pathlengths to locate the escape platforms and impaired performance in a probe trial. In addition, the FVB/N strain showed the most severe seizure response and mortality rate (62%) following administration of KA (30 mg kg-1, i.p.). These behavioural changes were also associated with a greater degree of cell body and synaptophysin loss in the pyramidal CA3 hippocampal cell layer and astrogliosis 72-h post-dose. These data suggest that the FVB/N strain may not be the most suitable background strain for the development of new transgenic mice for the study of genes implicated in the learning and memory process.

An approach to the diagnosis of chronic wrist pain.

A clinical algorithm was developed to help to establish a diagnosis in patients with chronic wrist pain. The accuracy of the algorithm was examined in a prospective blind study of 40 patients presenting to the Hand Unit with undiagnosed wrist pain and compared with the later findings at arthroscopy, which were believed to be as accurate as currently possible. Using simple examination techniques and conventional radiographs, an accurate diagnosis was made in 80% of cases. Examination techniques including the scapholunate shear test and the presence of local tenderness or pseudostability were found to be particularly accurate.

Population and resources in Mauritius.

"The island of Mauritius was facing a crisis by the 1950s as the relationship between its population and resources became unbalanced....A two-pronged strategy was set in place to change the relationship between population and resources. Firstly, an aggressive family-planning policy was established, reducing population growth. Secondly, the economy was diversified with tourism, financial services and, especially, manufacturing in the Mauritius Export Processing Zone, creating extra finance and resources. The changes have not been cost-free but Mauritius ends the century, not as a classic case of overpopulation, but more [as] a model micro-state that has overcome many population and resource problems, largely through its own efforts."

An approach to the diagnosis of chronic wrist pain.

A clinical algorithm was developed to help establish a diagnosis in patients with chronic wrist pain. The accuracy of the algorithm was examined in a prospective blind study of 40 patients presenting to the Hand Unit with undiagnosed wrist pain and compared with the later findings at arthroscopy, which were believed to be as accurate as currently possible. Using simple examination techniques and conventional radiographs, an accurate diagnosis was made in 80% of cases. Examination techniques including the scapho-lunate shear test and the presence of local tenderness or pseudostability were found to be particularly accurate.

Fracture of the lateral process of the talus: computed tomographic scan diagnosis.

Fracture of the lateral process of the talus is rare but can be mistaken for a simple ankle sprain. A case with normal conventional radiographs is presented to draw attention to this diagnosis in the resistant ankle sprain, and to highlight some of the problems that may be encountered with treatment.

Investigation of the irritable hip.

The respective roles of conventional radiography, ultrasound scanning, and radionuclide scintigraphy in the investigation of 62 children with the irritable hip syndrome are compared. It is recommended that conventional radiography and ultrasound scanning be routinely performed, but scintigraphy should be reserved for those with positive findings on ultrasound, as an abnormal scintigram is unusual in the presence of a normal ultrasound scan.

Dupuytren's and epilepsy revisited.

The incidence of Dupuytren's disease amongst the residents of two epileptic centres was found to be 12.0% in one and 38.1% in the other. The overall incidence at the second was significantly higher than a control population (16.0%) and this difference was particularly apparent in patients over 50 years old. The distribution of the Dupuytren's disease was found to be very similar to that of non-epileptic patients. At both centres, the disease process was more severe, with an increased incidence of contractures. Drug therapy was not clearly implicated in the aetiology of this condition.

The association between alcohol, hepatic pathology and Dupuytren's disease.

We have looked at the incidence of Dupuytren's disease in alcoholics, those with non-alcoholic liver disease and a control population. Both alcoholic patients and those with non-alcohol related liver disease had a higher rate (28% and 22% respectively) than the controls (8%), but this did not quite reach statistical significance (p greater than 0.05). In addition we found no Dupuytren's disease in 50 Egyptian patients with bilharzia and no consistent biochemical abnormalities in 134 patients with significant Dupuytren's disease. We conclude that alcoholics probably do have a higher rate of Dupuytren's disease and that this effect is largely due to the liver disease caused by alcohol abuse, but that the genetic factors are of greater aetiological importance.

The irritable hip. Scintigraphy in 192 children.

Over a 4-year period, 192 patients with a typical transient synovitis syndrome underwent radionuclide scintigraphy shortly after presentation. Three different patterns were found suggesting that all the cases may not be of the same etiology. Fifteen patients had evidence of ischemia of the femoral head, but only 4 patients went on to develop the typical radiographic features of Perthes' disease. The other 11 patients are thought to represent a minor, radiographically silent form of Perthes' disease.

The role of tissue pressure recording in forearm fractures in children.

During a 25-month period, 15 children with severe forearm fractures had signs and symptoms suggestive of an early compartment syndrome and underwent tissue pressure measurements. Of these, seven were found to have elevated intracompartmental pressures and had decompressive fasciotomies performed. The remaining eight patients had normal pressures and subsequently made uneventful recoveries. Tissue pressure recording is a useful adjunct to clinical diagnosis in suspicious cases of compartment syndrome, particularly in children.

The diagnostic potential of synovial effusion in meniscal pathology.

During a 20-month period, 382 arthroscopies were performed and the type of washout fluid obtained was noted. When a torn meniscus was found, the fluid was macroscopically abnormal in 97.4% of cases. A crystal clear washout was associated with no demonstrable pathology in over half the cases, the remainder having mainly patellofemoral joint pathology and other articular lesions. Only 6.3% of those with a clear fluid washout had meniscal pathology. Of those with abnormal fluid, 68% had meniscal pathology, with a normal arthroscopic examination being found in only 8.5%. In addition, when the fluid from traumatic effusions was examined microscopically, a typical droplet containing lipid crystals was found to be present and to account for an oily macroscopic appearance. These data support the use of fluid irrigation of the knee as a screening test for intraarticular pathology, especially of the menisci, that may allow a reduction in the number of negative arthroscopies.

Posterior dislocation of the elbow.

Posterior dislocation of the elbow is associated with significant morbidity and incomplete recovery. In this series of 32 patients, those with associated fractures, posterolateral dislocations, delayed reduction, and rigid immobilization had the least satisfactory outcome.

The significance of chondromalacic changes on the patella.

A total of 500 arthroscopies were performed in a 2-year period, with special reference made to the patellofemoral joint. In those with pain thought to be arising from this joint, 63% had chondromalacic changes on the posterior surface of the patella compared with a 45% incidence in those with meniscal pathological findings at arthroscopy. This study demonstrates that those with patellofemoral pain do not always have patellar articular changes, and patellar pathology is often asymptomatic. As a result, treatment directed at these lesions must be used with great caution.

Ulna neuropathy after elbow injury in children.

Six children developed seven cases of ulna neuropathy between 7 days and 6 years after significant elbow injury. None had evidence of acute nerve damage at the time of initial trauma. This complication, which develops soon after injury, has not been well documented. For this reason, the mode of presentation, treatment options, and review of the literature is presented.

Compartment syndrome following forearm fracture in children.

Six cases of acute compartment syndrome of the forearm following displaced fractures of the distal radius and ulna are presented. In children the diagnosis can be difficult to make, and can be helped by the use of compartment pressure measurements. Children with this type of fracture are at risk of developing this complication, and careful observation and assessment following injury is recommended. The use of early decompression has given better results in this younger age group than that reported in adults.