Radiographic prediction of failure after fixation of cervical hip fracture

During 1984-1985, 410 patients with cervical hip fracture were randomized between 2 methods of internal fixation-a single nail (Rydell) or 2 LIH hook pins (LIH). The patients were followed-up prospectively for at least 2 years. Radiographs were taken after 1 week, 1, 3, 6, 12, and 24 months. The radiographs of the 295 paients alive 2 years postoperatively were examined by one of the authors. The sliding and the diversion of the pins and the nail in the anteroposterior projection and the diversion in the lateral projection were measured. In the failure group (non-union, late segmental collapse), the greatest sliding was noted within 1 month postoperatively and the diversion increased up to 3 months. Significant differences between the failure and the non-failure groups could be seen even after 1 week. We also found that the degree of sliding of the LIH pins and the Rydell nail 1 month postoperatively is comparable to the scintigraphic pattern 2 weeks postoperatively in predicting failure after nternal fixation of cervical hip fractures.     

Urinary 5-Hydroxytryptophol: A Possible Marker of Recent Alcohol Consumption

Urinary 5-hydroxytryptophol (5-HTOL) is currently being evaluated as a marker of recent alcohol consumption. To compensate for urinary dilution, the molar ratio between 5-HTOL and 5-hydroxyindole-3-acetic acid (5-HIAA) is used. The 5-HTOL/5-HIAA ratio showed a satisfactory degree of individual stability when it was followed in a group of teetotallers for 1 month. The mean value of 5-HTOL/5-HIAA in a group of 69 persons abstaining from alcohol was 7.6 (pmoles 5-HTOL/nmoles 5-HIAA). Ninety-seven percent had values ranging from 4 to 17, with no value exceeding 20. A group of healthy volunteers were tested 12 hr after alcohol consumption and showed a dose-dependent and statistically significant elevation in the 5-HTOL/5-HIAA ratio. Four regular alcohol consumers who were followed during a period of 3 months of drinking had elevated values of the 5-HTOL/5-HIAA ratio in 60% of their urine samples. The present study indicates that urinary 5-HTOL/5-HIAA is a sensitive and reliable marker of recent alcohol consumption. We propose that a 5-HTOL/5-HIAA ratio greater than 20 (pmoles/nmoles) can be used to indicate recent alcohol consumption. This limit gives a low frequency of false positives; the statistical probability of having a value greater than 20 during abstinence from alcohol was calculated to be less than 0.001.     

Biological exposure limits estimated from relations between occupational styrene exposure during a workweek and excretion of mandelic and phenylglyoxylic acids in urine

Summary Styrene exposure of 18 workers in fiber-glass reinforced plastic industries was measured for 30-min periods throughout each workday for a week. The styrene uptake was estimated using pulmonary ventilation measurements. All urine voidings were collected separately and the styrene metabolites, mandelic acid (MA) and phenylglyoxylic acid (PGA) were determined. The relationship between both exposure and uptake versus excretion of these metabolites was studied. Styrene metabolite concentrations and excretion rates (with 95% tolerance limits) were calculated to correspond to a constant 8-h exposure at the Swedish exposure limit level (25 ppm) or an uptake of an exposure limit related styrene dose (6.3 mmol). The tightest tolerance limits were obtained for excretion rate of MA + PGA per 24 h. The calculated biological exposure limit was 3.4 (± 0.7) mmol MA + PGA/24 h for a dose of 6.3 mmol styrene.     

Closing patellar tendon defects after anterior cruciate ligament reconstruction: absence of any benefit

The most common graft in anterior cruciate ligament (ACL) surgery involves using the central one-third of the patellar tendon. Knowledge concerning the postoperative disability after harvesting the patellar tendon is, however, limited. The aim of this study was to evaluate the impact patellar tendon suture and bone grafting of the patellar bone defect might have in terms of functional outcome and patellofemoral pain after harvesting the bone-tendon-bone graft, compared with leaving the harvested site non-sutured and non-grafted. Sixty patients, scheduled for arthroscopically assisted ACL reconstruction, were randomly allocated to two groups. In group I, suture of the patellar tendon and bone grafting of the patellar defect were performed. In group II, the tendon gap and the patellar defect were left open. Preoperatively, there was no significant difference between the groups when comparing objective knee stability, as measured with a KT-1000 laxity meter, Lysholm score, Tegner activity level, IKDC score, or patellofemoral pain score. Both groups had a significantly improved Lysholm score at the 2-year follow-up, without any difference between them. Tegner's activity level was significantly lower at follow-up, compared with the pre-injury level in both groups. The patellofemoral pain score improved significantly after the reconstruction, without any difference between the groups. Ultrasonography did not reveal any difference between the groups in terms of healing of the tendon gap. This study revealed no differences in donor site morbidity, functional outcome, patellofemoral pain score or knee joint stability between the two treatment groups. The conclusion is that suture of the patellar tendon and bone grafting of the patellar defect do not improve the functional results or reduce donor site morbidity after arthroscopically assisted ACL. Received: 17 December 1996 Accepted: 30 July 1997     

Evaluation of the image quality of ink-jet printed paper copies of digital chest radiographs as compared with film: A receiver operating characteristic study

Paper copies of digital radiographs printed with the continuous ink-jet technique have proved to be of a high enough quality for demonstration purposes. We present a study on the image quality of ink-jet printed paper copies of digital chest radiographs, based on receiver operating characteristic (ROC) analysis. Eighty-three digital radiographs of a chest phatom with simulated tumors in the mediastinum and right lund, derived from a computed radiography (CR) system were presented in two series of hard copies as ink-jet printed paper copies and as laser recorded film. The images, with a matrix of 1,760×2,140 pixels, were printed with a spatial resolution of 10 pixels/mm in the CR film recorder as well as in the ink-jet printer. On film, every image was recorded in two versions, one optimized for the mediastinum and one for the lungs. On paper, only one image was printed; this constituted an effort to optimize both the mediastinum and the lungs. The ink-jet printed images, printed on a matt coated paper, were viewed as on-sight images with reflected light. The exdaminations were reviewed by six radiologists, and ROC curves were constructed. No significant difference was found between the performance of film and that of ink-jet paper prints. Because the cost for a paper copy is only a tenth of that of film, remarkable cost reductions can be achieved by using the ink jet technique instead. Our results show that further quality studies of ink-jet printed images are worthwhile.     

Biochemical, Enzymatic, and Serological Differentiation of Peptococcus indolicus (Christiansen) Sørensen from Peptococcus asaccharolyticus (Distaso) Douglas

Peptococcus indolicus (formerly Micrococcus indolicus) is an asaccharolytic anaerobic coccus that is frequently isolated from udder secretions from cases of heifer and dry-cow mastitis (summer mastitis). To facilitate better identification and its differentiation from Peptococcus asaccharolyticus, a variety of biochemical, enzymatic, and serological properties were studied. Seventy-nine strains of P. indolicus of bovine origin and 10 strains of P. asaccharolyticus of human origin were examined using the API 20A and API-ZYM test kit systems. In addition, production of extracellular enzymes by using sensitive substrate-containing agar plate tests, production of peptocoagulase (a plasma-clotting factor), hemolytic properties, metabolic end products by gas chromatography, and serological characteristics with a set of P. indolicus typing antisera were investigated. P. indolicus and P. asaccharolyticus were not satisfactorily differentiated solely by the API 20A system. P. indolicus differed from P. asaccharolyticus in producing H(2)S, reducing nitrate to nitrite, producing peptocoagulase, possessing alkaline phosphatase, and producing large amounts of propionate from lactate. Moreover, none of the strains of P. asaccharolyticus was typable with the P. indolicus typing antisera. The majority (88%) of P. indolicus strains also gave weak hydrolysis of ribonucleic acid, and 6 out of 79 produced deoxyribonuclease. All strains in this study were sensitive to metronidazole (5 mug) by disk diffusion tests.     

Comparison of five methods, including the PDM Epsilometer test (E test), for antimicrobial susceptibility testing of Pseudomonas aeruginosa.

The antimicrobial susceptibilities of 100 clinical isolates of Pseudomonas aeruginosa to six antipseudomonal antibiotics were tested by five methods: the National Committee for Clinical Laboratory Standards (NCCLS) methods for broth microdilution, agar dilution, and agar disk diffusion; the Vitek Automicrobic System method (Vitek Systems, Hazelwood, Mo.); and the PDM Epsilometer test (E test) (AB Biodisk, Solna, Sweden). The E test results showed excellent correlation with agar dilution results, with over 90% agreement within 1 doubling dilution between the E test and reference agar dilution MICs for all antimicrobial agents tested. The E test results also showed good correlation with the results from the reference agar disk diffusion method, with 90 to 99% complete agreement and 100% essential agreement on categories for all antibiotics tested (essential agreement is the agreement obtained when minor discrepancies are ignored). Comparison of categories with the E test and broth microdilution methods, using the broth microdilution method as the reference method, gave only 59% complete agreement for gentamicin, with 28 minor discrepancies and 13 very major discrepancies. Some discrepancies were observed between results from the E test and broth methods for gentamicin, with the broth microdilution and Vitek methods giving higher MICs than the E test and other methods using agar. The most recent NCCLS guidelines for broth dilution testing have reduced the recommended levels of cation supplementation, which may enhance future agreement between results for the aminoglycosides and P. aeruginosa on broth and on agar. We found that the E test offers a simple, labor-efficient, and accurate method for MIC determination on an agar medium.