Lawn mower injuries of the pediatric foot and ankle: observations on prevention and management

We reviewed 32 children with lower extremity injuries caused by power lawn mowers. Functional outcome of 21 patients was evaluated. Anatomical injury patterns provide some guidelines in management and prediction of functional outcome. Consistently, the most severe injuries result from ride-on mowers and wounds to the posterior/plantar foot and ankle. Our experience with pediatric foot and ankle lawn mower injuries permits recommendations for maximum functional outcome with minimal intervention. Public awareness and mower safety devices may be required to decrease the rate of accidents in the future.

Adolescent femoral shaft fractures: rigid versus flexible nails

Twenty-one skeletally immature patients between 11 and 16 years of age were treated operatively for a unilateral femoral shaft fracture. Eleven patients underwent fixation with flexible nails and 10 with rigid nails. The patients were studied retrospectively to determine the similarity of the groups. Each method of fixation was then compared to determine the technical ease and final outcome. Both methods gave excellent final radiographic alignment with minimal complications. Flexible nailing required much less operative time and less fluoroscopy time. Estimated cost of using Ender nails is much less than using Russell-Taylor interlocking nails.

Introgression of wild species into the cultivated strawberry using synthetic octoploids

Synthetic octoploids reresent one method of integrating wild species germplasm into the cultivated octoploid strawberry. Several strawberry genotypes derived from Guelph synthetic octopoloids and 3-4 generations of outcrossing were evaluted for horticultural performance. Pollen stainability of the genotypes was improved by outcrossing and selection and was not considered a limiting factor to yield. Yield and berry weight of the genotypes improved to a level where several genotypes had yields as good as, or greater than, the mean of the check cultivars. There was no significant difference in the yield of genotypes that were either three or four outcrosses removed from the synthetic octoploids. Some genotypes displayed an everbearing habit accompanied by poor runnering characteristics which may have contributed to their reduced yield in the second season. Synthetic octoploids are composed of a diversity of germplasms distinct from the cultivated octoploid. However, by carefully selecting parents for the outcrossing program and rigorous selection for important horticultural traits, it was possible to restore performance close to the elite level in as few as three generations.

Effect of a selective protein kinase C inhibitor, Ro 31-8425, on Mac-1 expression and adhesion of human neutrophils

The role of protein kinase C (PKC) in mediating up-regulation of macrophage 1 adhesion protein (Mac-1) and adhesion of neutrophils in response to physiological agonists is not clear. Previous studies have relied on use of phorbol esters to activate PKC directly or on results obtained with non-selective inhibitors of protein kinases. 3-[8-(Aminomethyl)-6,7,8,9-tetrahydropyridol[1,2-a]-indol-10-yl]-4 -(1- methyl-3-indolyl)-1H-pyrrole-2,5-dione hydrochloride (Ro 31-8425) is a potent and highly selective inhibitor of PKC (Bit et al. J. Med. Chem. 1993. 36: 21). In these studies Ro 31-8425 has been used to define, more definitively, the role of PKC in mediating complement fragment C5a (C5a)-stimulated up-regulation of Mac-1 and adhesion of neutrophils to endothelial cells and to bovine serum albumin (BSA)-coated plastic. Phorbol 12, 13 dibutyrate (PBu2) increased surface expression of Mac-1 and stimulated adhesion of neutrophils to endothelial cells and to BSA-coated plastic. This confirms previous reports that activation of PKC can stimulate these responses. The PKC inhibitor, Ro 31-8425, inhibited the PBu2-stimulated responses, which confirms that Ro 31-8425 was effective in inhibiting PKC in these neutrophils. A more physiological agonist, C5a, also increased surface expression of Mac-1 and adhesion of neutrophils to endothelial cells and BSA-coated plastic. However, the responses to C5a were unaffected by Ro 31-8425. These results suggest that, although activation of PKC can promote up-regulation of Mac-1 and adhesion of neutrophils, this does not appear to be the physiological pathway. A non-selective protein kinase inhibitor, staurosporine, inhibited both PBu2 and C5a-stimulated adhesion. This suggests that a protein kinase other than PKC, possibly a tyrosine protein kinase, is likely to be involved in mediating C5a-stimulated Mac-1 up-regulation and adhesion. These results emphasise the need for caution in interpreting experiments and assuming a role for PKC. Use of a potent and selective inhibitor of PKC, Ro 31-8425, provides more definitive information.

Development of the Hearing in Noise Test for the measurement of speech reception thresholds in quiet and in noise

A large set of sentence materials, chosen for their uniformity in length and representation of natural speech, has been developed for the measurement of sentence speech reception thresholds (sSRTs). The mean-squared level of each digitally recorded sentence was adjusted to equate intelligibility when presented in spectrally matched noise to normal-hearing listeners. These materials were cast into 25 phonemically balanced lists of ten sentences for adaptive measurement of sentence sSRTs. The 95% confidence interval for these measurements is +/- 2.98 dB for sSRTs in quiet and +/- 2.41 dB for sSRTs in noise, as defined by the variability of repeated measures with different lists. Average sSRTs in quiet were 23.91 dB(A). Average sSRTs in 72 dB(A) noise were 69.08 dB(A), or -2.92 dB signal/noise ratio. Low-pass filtering increased sSRTs slightly in quiet and noise as the 4- and 8-kHz octave bands were eliminated. Much larger increases in SRT occurred when the 2-kHz octave band was eliminated, and bandwidth dropped below 2.5 kHz. Reliability was not degraded substantially until bandwidth dropped below 2.5 kHz. The statistical reliability and efficiency of the test suit it to practical applications in which measures of speech intelligibility are required.

A comparison of Wisconsin instrumentation and Cotrel-Dubousset instrumentation

Twenty-six patients who underwent Wisconsin instrumentation and 36 patients who underwent Cotrel-Dubousset instrumentation (CDI) for idiopathic scoliosis were studied. Inclusion in the study required at least 24-month follow-up. Variables compared included operating time, blood loss, frontal plane correction, axial and sagittal plane changes, effects on compensation, and complications. In general, operating time, blood loss, and instrumentation problems were greater with CDI. Thoracic curve correction in King II curves was better with CDI. There was no advantage to either system with respect to sagittal plane alignment or rotation. When all factors were considered, a significant advantage to use of CDI could not be demonstrated.

Is pinning in situ a safe procedure for slipped capital femoral epiphysis?

This report reviews the results of 37 patients with 46 involved hips treated with pinning for slipped capital femoral epiphysis. Particular attention was given to incidence of complications, including avascular necrosis, chondrolysis, and penetration of the joint. Of 46 hips with 1-year follow-up, there were no cases of chondrolysis. Of 23 hips with 2-year follow-up, there was only 1 case of avascular necrosis. Pin penetration, recognized at the time of surgery, produced no significant sequelae. Pinning can produce satisfactory results without a significant incidence of major complication.

Capitellocondylar total elbow replacement in rheumatoid arthritis. Long-term results

We evaluated the long-term results of 202 capitellocondylar total elbow replacements that had been performed, from July 1974 through June 1987, in 172 patients. The duration of follow-up averaged sixty-nine months (range, twenty-four to 178 months). At the most recent follow-up examination, use of a 100-point rating score demonstrated an improvement from an average preoperative score of 26 points (range, 2 to 50 points) to an average postoperative score of 91 points (range, 45 to 100 points). The most improvement occurred in the categories of relief of pain, functional status, and range of motion in all planes except extension. The improvements in these categories and in the roentgenographic appearance that were seen in the early postoperative period did not deteriorate with time. The average preoperative arc of motion at the elbow ranged from -37 degrees of extension to 118 degrees of flexion. The average postoperative arc of motion at the elbow ranged from -30 degrees of extension to 135 degrees of flexion. Supination improved from 45 degrees preoperatively to 64 degrees postoperatively; pronation improved from 56 degrees preoperatively to 72 degrees postoperatively. The roentgenograms showed a radiolucent line adjacent to eight humeral and nineteen ulnar components; most of the lines were incomplete and one millimeter wide or less. Revision of the prosthesis was necessary in three elbows (1.5 per cent) because of loosening without infection, and in three additional elbows because of dislocation of the prosthesis. Complications included deep infection in three elbows (1.5 per cent); problems related to the wound in fifteen (7 per cent); permanent, partial sensory ulnar-nerve palsy in five (2.5 per cent); permanent, partial motor ulnar-nerve palsy in one (0.5 per cent); and dislocation in seven (3.5 per cent).

Functional recovery in rabbit heart after preservation with a blood cardioplegic solution and perfusion

Thirty-five isolated rabbit hearts were subjected to 60 minutes of storage after cardiac arrest with high K+ crystalloid cardioplegic solution at 5 degrees C. They were divided into five groups (n = 7 per group) according to the preservative protocol: group I (simple immersion in 0 degrees C normal saline solution), group II (simple immersion in 30 degrees C blood cardioplegic solution), group III (immersion and perfusion in 30 degrees C blood cardioplegic solution), group IV (simple immersion in 10 degrees C blood cardioplegic solution), and group V (immersion and perfusion in 10 degrees C blood cardioplegic solution). After storage for 1 hour, cardiac function, tissue water content, and the number of hearts capable of ejecting against a 100 cm H2O column afterload were recorded and compared among the five groups. Cardiac function in group II was not different from group I. Aortic pulse pressure and left ventricular developed pressure were lower in group II than in group III, IV, or V. Aortic developed pressure was higher in groups III and V (p < 0.05). Tissue water content in group I was significantly higher than in groups II, III, and V (p < 0.05). All hearts in groups III and V could eject against a 100 cm H2O afterload after preservation (p < 0.05 versus groups I, II, and IV). Factorial analysis among the groups using blood cardioplegic solution showed that either hypothermia or perfusion alone or the combination was a protective factor in providing functional recovery of stored hearts.(ABSTRACT TRUNCATED AT 250 WORDS)

Does hypothermia or hyperventilation affect enflurane MAC reduction following partial cardiopulmonary bypass in dogs?

This study in dogs determined the effect of systemic cooling and arterial hypocarbia during cardiopulmonary bypass (CPB) on the requirements for enflurane anaesthesia (MAC) before and after CPB. Twelve mongrel dogs were each anaesthetized with enflurane in oxygen on two separate occasions. End-tidal enflurane concentration was measured with a Puritan-Bennett Anaesthesia Agent Monitor. Using the tail-clamp method, MAC was determined twice with a one-hour interval between measurements (MAC 1 and MAC 2). Partial CPB was then initiated using femoral arterio-venous cannulation and maintained for one hour. Following separation from CPB, MAC was again determined twice with a one hour interval between measurements (MAC 3 and MAC 4). Dogs were randomly assigned according to PaCO2 management during CPB (low, 17.6 +/- 8.6 mmHg vs high, 38.9 +/- 11.5 mmHg), and then subjected to two experimental conditions. The first experiment on each dog was undertaken using normothermia during CPB (warm, 35-37 degrees C) while the second experiment (at least two weeks later) was conducted using hypothermia during CPB (cold, 30 degrees C). Analysis of the data, using ANOVA for repeated measures, revealed MAC 3 (1.95 +/- 0.33%, post-CPB) to be reduced when compared with MAC 1 (2.18 +/- 0.28%, P < 0.01) or MAC 2 (2.10 +/- 0.22%, P < 0.01), determined before CPB. Multivariate repeated measures analysis revealed no independent effects of hypothermia or arterial hypocarbia during CPB, on MAC reduction. By the time of the second experiment in each dog (two weeks later), MAC had returned to baseline levels.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of prestorage irradiation on posttransfusion red cell survival

Transfusion-associated graft-versus-host disease (TA-GVHD) may occur whenever immunologically competent allogeneic lymphocytes are transfused to an immunocompromised recipient. Irradiation of blood components eliminates the risk of TA-GVHD but may damage the cellular elements in the transfused component, particularly if the cells are stored for prolonged periods in the irradiated state. To study the effect of irradiation on long-term storage of red cells, AS-1 red cells from eight normal subjects were prepared on two occasions. On one occasion, the units were stored as standard AS-1 red cells for 42 days at 4 degrees C; on the other, they were exposed to 3000 cGy radiation within 4 hours of collection and then were stored as AS-1 red cells for 42 days at 4 degrees C. The donations were at least 12 weeks apart. Irradiated units demonstrated significant elevations in poststorage plasma hemoglobin (Hb) (623 +/- 206 vs. 429 +/- 194 g/dL [6230 +/- 2060 vs. 4290 +/- 1940 g/L], p less than 0.02) and plasma potassium (78 +/- 4 vs. 43 +/- 9 mEq/L [78 +/- 4 vs. 43 +/- 9 mmol/L], p less than 0.01) and significant decreases in red cell ATP (1.9 +/- 0.2 vs. 2.1 +/- 0.3 microM/g Hb, p less than 0.04) and 24-hour posttransfusion red cell recovery (68.5 vs. 78.4%, p less than 0.02), as compared to nonirradiated units. It can be concluded that irradiation with 3000 cGy damages red cells and that long-term storage in the irradiated state may enhance this damage. Red cells should not be stored for 42 days after irradiation with 3000 cGy.

Butyltin and copper monitoring in a Northern Chesapeake Bay marina and river system in 1989: An assessment of tributyltin legislation

This study was designed to: (1) evaluate dibutyltin (DBT) and tributyltin (TBT) bi-weekly in the water column for four months during the peak boating season (June-September, 1989) at seven stations in the Back Creek and Severn River area of Maryland waters of Chesapeake Bay; (2) compare butyltin values from the 1989 study with values obtained from a similar butyltin monitoring study conducted in 1988 (after Maryland TBT legislation) and 1986 (before Maryland TBT legislation); (3) determine the extent of TBT paint use in the Back Creek area by surveying boat owners; (4) determine dissolved copper concentrations from three of the seven stations bi-weekly during the four-month study; and (5) compare dissolved copper concentrations at these stations with previous copper data collected in 1988.Mean four-month DBT concentrations ranged from 10 to 73 ng/L at the seven stations. Highest DBT concentrations occurred at Station 1 in a marina; lowest concentrations occurred at Station 7 in the Severn River. Mean four-month TBT concentrations ranged from 177 ng/L at Station 1 (marina) to 21 ng/L at Station 7 (Severn River). Maximum TBT concentrations of 361 and 570 ng/L occurred at marina SDtations 1 and 3, respectively. Temporal trends in both DBT and TBT (station mean concentrations by date) showed that peak concentrations occurred during the early part of the boating season followed by reductions in late summer and early fall. Spike concentrations of both DBT (117 and 62 ng/L) and TBT (308 and 366 ng/L) were reported on two sampling dates near a boat maintenance facility in Back Creek.There was a significant reduction in DBT concentrations from 1986 to 1989 when date was treated as a fixed effect. However, TBT concentrations were not significantly reduced between 1986 and 1989 when mean concentrations of TBT were averaged across stations and dates for each year. A significant reduction was reported at Station 1 (marina station) when each station was examined for differences between years. TBT was also reported to significantly decrease (p=0.0442) at Station 7 between 1988 and 1989. A boat owner survey in the study area showed that 6% of the recreational boats that were surveyed were painted with TBT paint in 1989. This was a significant decrease in TBT paint use from the previous year when 31% of recreational boat owners surveyed used TBT paints.An evaluation of dissolved copper concentrations at three stations in the study area in 1989 showed that mean concentrations from bi-weekly sampling for four months was 10 μg/L at Station 1, 7.8 μg/L at Station 4 and 2.7 μg/L at Station 7. Copper concentrations decreased with distance away from the Back Creek marinas. Copper concentrations at all three stations were significantly lower in 1989 than in 1988.

Amplification for listeners with steeply sloping, high-frequency hearing loss

Two experiments were conducted to determine the effects of various upper cutoff frequencies on performance of listeners with steeply sloping, high-frequency hearing loss. The upper cutoff frequency of individually prescribed responses was systematically adjusted to 0.71, 1.79, and 6.0 kHz. Measures of nonsense syllable recognition and subjective ratings of speech intelligibility and speech quality were obtained at three overall gain settings for each frequency response. Experiment 1 assessed performance on tests in quiet and Experiment 2 assessed performance on tests in noise. Nonsense syllable recognition improved as the upper cutoff frequency increased, particularly for tests in noise. In contrast, the subjects gave significantly poorer quality ratings for the shaped response with the highest cutoff frequency (6.0 kHz). Few significant effects of cutoff frequency were found for ratings of intelligibility in either quiet or noise.

Hip stabilization in severely involved cerebral palsy patients

Thirty-two patients (48 hips) with total body involved cerebral palsy (CP) underwent medial release and proximal femoral osteotomy for hip subluxation or dislocation. Twenty-eight hips were rated good, 15 were rated fair, and five were rated poor at follow-up. The better located the hip preoperatively and the better the reduction obtained at operation, the better the final result. The major factor that correlated with a good result was early operation, performed before significant deformity had occurred.

The accuracy of tibial intramedullary alignment devices in total knee arthroplasty

The accuracy of a tibial medullary alignment device is assessed radiographically in 30 varus and 30 valgus knees undergoing total knee arthroplasty. The results suggest that although the device is reliable and accurate for varus knees, it may lead to malalignment of up to 5 degrees in valgus knees. Overall neutral alignment was achieved in 83% of the varus knees and 37% of the valgus knees. Tibial bowing was the main source of error and was present in 66% of the valgus knees, with mean of 3 degrees. Preoperative long films or cross-checking with external alignment devices is recommended to assure neutral alignment in genu valgus deformity.

Does cardiopulmonary bypass alter enflurane requirements for anesthesia?

This study on dogs determined whether the requirement for enflurane anesthesia was different pre- versus postcardiopulmonary bypass (CPB). Male mongrel dogs (n = 16) were anesthetized with enflurane in oxygen. Tracheal intubation was performed, monitors placed, and end-tidal enflurane concentration measured via a Puritan-Bennett Anesthesia Agent Monitor. MAC was determined by the tail-clamp method. CPB was then initiated using aortoatrial (n = 6, group 1) or femoral artery-vein (n = 4, group 2) cannulation or none (n = 6, group 3, control). CPB was maintained for 1 h using a bubble oxygenator, a crystalloid prime, and flows of approximately 70-80 ml/kg with a mean systemic pressure maintained between 50-70 mmHg. Following separation from CPB, MAC was again determined. The reduction in enflurane MAC following CPB was 30.1 +/- 21.5% (mean +/- SD; P less than 0.05 vs. pre-CPB) in group 1 but there was a wide range of reduction produced (3.8-58.8%). The degree of MAC reduction (19.8 +/- 8.6%; P less than 0.05 vs. pre-CPB) produced by CPB in group 2 was much less variable in degree (range 13.0-32.4%) but did not differ from group 1. Although pre- versus post-CPB mean systemic pressure fell from 83 +/- 13 to 69 +/- 15 mmHg (P less than 0.05), this is above the level likely to produce a reduction in MAC. No other significant hemodynamic changes were observed. Temperature pre- versus post-CPB was not different. The degree of hemodilution and acid-base disturbances are unlikely to be the explanation.(ABSTRACT TRUNCATED AT 250 WORDS)

Clubfoot release without wide subtalar release

Fifty-two feet treated by clubfoot release without wide subtalar release were evaluated 4.2-10.8 years after surgery. Eleven feet (21%) had undergone additional operative procedures at the time of review, and 82% of feet had good or excellent functional ratings at that time. The mean talocalcaneal index was 49 degrees (range 12-76 degrees), indicating that correction of the subtalar joint occurred in some patients. This procedure satisfactorily corrects many feet but undercorrects some. Overcorrection was rare. Foot progression angles were also determined and are reported in an accompanying article.

Ligamentous injuries of the knee in children

Ligamentous injuries, although uncommon in the skeletally immature patient, can be found in isolation or associated with physeal injury or long-bone fracture. Four new cases of ligamentous injury in the child show that recognition and management of these injuries are important to achieve good recovery. In addition to history and physical examination, standard and stress roentgenographs, examination under anesthesia, and arthroscopy are important for early diagnosis.

Career trends of master's prepared family nurse practitioners

The purpose of this study was to examine the career trends of family nurse practitioner (FNP) graduates of one master's program. A questionnaire was mailed to all FNPs (N = 113) who graduated 1-11 years earlier; there was a response rate of 83%. The survey revealed that for both first and present jobs the majority were providing direct patient care as a primary care provider or practicing in an indirect role. The study findings indicate that for these graduates there is a long term commitment (demonstrated through continued employment) as well as opportunity to practice in the nurse practitioner role in a direct or indirect capacity.

How to make informed employment decisions

This article presents a frame-work for organizing information gained during the employment search process and suggests questions to ask that are representative of current healthcare system changes. With an organized approach and the right questions, the nurse can avoid the perils of an uninformed employment decision.

Giant cell reaction in a phalangeal bone

A case of the rare and non-neoplastic lesion, giant cell reaction of bone, is described. The pathological and radiological features of this lesion are reviewed and an aetiological mechanism is proposed to account for its unique histopathological features. Recognition of this lesion and its non-neoplastic nature are important so as to avoid surgical ablation of the affected bone.

Surgical repair of stenotic ostial lesions of the left main coronary artery

Fourteen patients with isolated stenosis of the left coronary artery ostium underwent vein patch angioplasty. An anterior approach between the aorta and pulmonary artery to expose the left main coronary ostium was used in 12 of 14 patients. There were no deaths, and postoperative angiograms in 13 of the patients showed normal coronary ostial contour with normal runoff. Two perioperative myocardial infarctions were observed. Four of the 14 patients underwent an urgent operation. Isolated coronary ostial stenosis appears to be a distinct clinical entity occurring in younger patients, mostly female, and often with a short clinical course. Unstable pain and hemodynamics are observed. The common pathologic cause of the stenotic lesion is not clear.