Late open reduction internal fixation of lateral condyle fractures.

To study the effects of late open reduction of lateral condyle fracture (LCF) on avascular necrosis (AVN), amount of displacement, and improvement, the records of 11 children with an open capitellar physis and a malunion or a nonunion treated >3 weeks after injury were reviewed. Preoperative and postoperative displacement amounts were recorded. Radiographs were reviewed for AVN, lateral overgrowth, or fishtail deformity. There were no cases of AVN. Three patients had occasional pain. Four patients had displacement of >10 mm before surgery. In fractures with >1 cm of displacement, fragment position was minimally improved surgically, but final alignment and range of motion were good. These fractures showed more radiographic deformities at the time of late open reduction. The risk of AVN with late open reduction of LCF at >3 weeks is reduced if no tissue is stripped off the fracture fragment posteriorly. Even children without anatomic reduction had functional arms with little or no pain.

Combined asymptomatic congenital anterior and posterior deficiency of the atlas.

Atlas anomalies in terms of clefts and aplasia are rare. They can sometimes simulate fractures and need further evaluation. Imaging in terms of CT and MR can help resolve diagnostic confusion and also outline associated neurological involvement. A rare anomaly of anterior and posterior atlas arch, previously unclassified, is presented.

Prevalence of positive preoperative pregnancy testing in teenagers scheduled for orthopedic surgery.

The pregnancy status of female teenagers presenting for orthopaedic surgery is often unknown. Anesthetics may have teratogenic or abortive effects. The authors report the results of a screening program for unrecognized pregnancy in 532 female teenagers presenting for orthopaedic surgery. Five patients with a positive urine human chorionic gonadotropin test were identified, for a prevalence of 1 positive result in 106 patients tested (0.9%). Surgery was cancelled in each case.

Comparison of morphine patient-controlled analgesia with and without ketorolac for postoperative analgesia in pediatric orthopedic surgery.

The purpose of this prospective, randomized, double-blind, placebo-controlled clinical study was to determine whether the administration of intravenous ketorolac, coadministered with morphine patient-controlled analgesia (PCA), demonstrates an opioid-sparing effect, provides improved analgesia, and reduces the incidence of opioid-induced side effects in children after orthopedic surgery. The findings of enhanced analgesia with decreased opioid use suggest that coadministration of ketorolac with morphine PCA is beneficial for the treatment of pain in children after orthopedic surgery.

Immunohistochemical analysis of lens epithelial-derived membranes following cataract extraction in the dog.

The objective of the study was to characterize the morphologic and immunohistochemical features of lens epithelial-derived proliferative membranes from the anterior segment of canine globes. These features were correlated with those previously identified for diseases resulting from lens epithelial cell (LEC) proliferation including posterior capsular opacification, traumatic subcapsular cataract, and subcapsular plaques associated with hypermature cataracts. Sixteen canine globes were removed as a result of glaucoma or other complications following cataract extraction. Light microscopic and immunohistochemical analysis was performed on sections from formalin-fixed, paraffin-embedded globes. The tissues were stained with a variety of antibodies for cellular markers for LECs, growth factors or other cellular constituents relevant to cellular metaplasia and proliferation. The membranes were composed of monolayers or multilayers of spindle-shaped cells on the external surfaces of the anterior and posterior lens capsule, ciliary processes, iris leaflets, and iridocorneal angle, and they could be seen extending from an obvious monolayer of LEC within the capsular sac. Variably, scattered pigment cells, presumably of uveal origin, were concurrently present. Cellular components of the membranes stained positive for vimentin, transforming growth factor-beta, basic fibroblast growth factor, and smooth muscle actin. An amorphous eosinophilic extracellular matrix consisting predominately of collagen was associated with the membranes. Proliferative anterior segment membranes following cataract surgery were morphologically and immunohistochemically similar to cellular and matrix components of posterior capsular opacification and capsular plaques seen with hypermature cataracts, both of which result from metaplasia and proliferation of LEC. The presence of these LEC-derived membranes in association with secondary glaucoma suggests that exuberant proliferation of LEC outside the confines of the lens capsular sac may cause pathologic alterations in the eye following cataract surgery in the dog.

Musculoskeletal coccidioidomycosis. A review of 25 cases.

Coccidioidomycosis is a fungal infection endemic to the southwestern United States. Musculoskeletal involvement is rare, and there are few reports with clear recommendations regarding treatment. The purpose of this study was to review a series of 25 patients with musculoskeletal coccidioidomycosis and to assess their outcomes with respect to presentation and treatment. There were 36 lesions among the 25 patients, 8 located in the spine, with the remainder distributed throughout the body. Seventeen patients had a delay in diagnosis of more than 1 month. Eight patients had an elevated white blood cell count, and 10 had an elevated sedimentation rate. Only 7 of the patients had an overt pneumonia before the musculoskeletal presentation. Twenty-four patients underwent formal irrigation and debridement and 22 patients had at least 1 course of Amphotericin B. The average followup after the initiation of treatment was 3.5 years, ranging from 2 to 10 years. Seven patients had recurrent lesions that required further surgical intervention, 4 of whom had a delay in diagnosis of more than 1 month. There were 3 deaths. All surviving patients were free of disease at final followup.

The safety of continuous epidural infusion for postoperative analgesia in pediatric spine surgery.

Epidural analgesia and anesthesia are standard regional techniques in orthopaedic surgery of the lower extremities. Benefits of epidural anesthetic infusions include excellent analgesia, minimal respiratory depression, no somnolence, and decreased need for blood transfusion. Adverse effects include pruritus, nausea, and urinary retention, but standard methods have evolved to counter each adverse effect. A continuous epidural infusion of opioid and bupivacaine was used as the principal postoperative analgesic for 71 young patients undergoing surgery for the correction of spinal deformity. The infusion was titrated to a point at which each patient denied having any pain and was maintained for an average of 2.9 days. Sixty-four patients experienced satisfactory analgesia with minimal adverse effects. The technique worked despite multiple laminotomies for segmental fixation and did not compromise neurologic assessment. We conclude that epidural analgesia is as safe and effective after spinal-deformity surgery as it is after other types of surgery.

Calcitonin increases transcription of parathyroid hormone-related protein via cAMP.

Transcriptional regulation of the human parathyroid hormone-related protein (PTHrP) gene by calcitonin was examined in a lung cancer line (BEN cells). Northern analysis demonstrated that calcitonin caused a rapid 4.5-fold elevation in PTHrP mRNA. Transient transfection of a construct containing 1119 base pairs of the human PTHrP gene 5' to the ATG start site of translation, fused to the CAT reporter sequence, was used to demonstrate a five-fold increase in transcription by calcitonin. Similar increases were also observed when transfected cells were exposed to a number of cAMP agonists including forskolin, as well as isobutyl-methylxanthine. A putative cAMP responsive element (5'-TGACTTCA-3') present within exon 4 was placed upstream of the heterologous SV40 promoter. Expression of this construct was elevated 4.5-fold in response to calcitonin and 7-fold in response to forskolin. Similar responses to calcitonin occurred with a smaller construct (pZMR30) containing 530 bp of sequence upstream of the ATG start site. Thus we postulate that calcitonin acts at least partially via cAMP through this element in exon 4 of the human PTHrP gene.

DNA sequences in the rat osteocalcin gene that bind the 1,25-dihydroxyvitamin D3 receptor and confer responsiveness to 1,25-dihydroxyvitamin D3.

The 5' flanking region of the rat osteocalcin gene has been shown to confer responsiveness to 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] after transfection of fusion genes into ROS 17/2.8 cells. Deletion analysis has demonstrated that there are at least two domains in this 5' flanking region that contribute to 1,25(OH)2D3 responsiveness; however, only the downstream region is able to confer 1,25(OH)2D3 responsiveness to either the native osteocalcin promoter or to a heterologous viral promoter (herpes simplex virus thymidine kinase). The proximal region responsible for 1,25(OH)2D3 induction of the rat osteocalcin gene lies 458 base pairs upstream from the transcription start site of this gene. A 25-base-pair oligonucleotide corresponding to the sequences in this region is able to confer 1,25(OH)2D3 responsiveness to the thymidine kinase promoter in an orientation-independent fashion. This sequence contains three copies of a short sequence that are homologous to "half-sites" of steroid response elements. Gel-retardation assays using porcine intestinal nuclear extract as a rich source of 1,25(OH)2D3 receptor demonstrated retardation in the migration of probes containing the sequence noted above. A monoclonal antibody directed against the 1,25(OH)2D3 receptor caused further retardation in the migration of these protein-DNA complexes. Therefore, the sequences represented in this oligonucleotide encompass the sequences necessary for binding of the 1,25(OH)2D3 receptor to DNA as well as those sequences necessary for 1,25(OH)2D3 to induce osteocalcin gene transcription.

Pediatric update #10. Treatment of displaced supracondylar fractures of the humerus in children by closed reduction and percutaneous pinning.

In a retrospective study of 25 displaced supracondylar fractures of the humerus in children, treatment by closed reduction and percutaneous pin fixation was reviewed. Follow-up averaged 16 months. Loss of elbow motion and carrying angle were graded according to Flynn's criteria. Twenty-two patients' results were rated excellent, two were good, none was fair, and one was poor. There were no complications reported. Comparison of the values of Baumann's angle obtained from intraoperative, postreduction roentgenograms with those of the opposite, normal elbows predicted the final carrying angles within two degrees in 14 of 17 cases and within five degrees in all 17 cases where such comparison was possible. We conclude that this technique is safe and effective and recommend the use of Baumann's angle as a standard to judge the quality of reduction.

Acute carpal tunnel syndrome secondary to septic arthritis of the wrist.

A case of acute carpal tunnel syndrome secondary to septic arthritis of the wrist is reported. Treatment consisted of carpal tunnel release, incision and drainage of the wrist joint, intravenous injection of antibiotics, and delayed primary closure. The infection resolved and median nerve function promptly returned to normal. We believe this is the first report of septic arthritis of the wrist as a cause of acute carpal tunnel syndrome.

Four cases of injury involving soda vending machines.

Injuries resulting from rocking soda vending machines are severe and potentially fatal. Four cases of significant trauma stemming from soda vending machine accidents are reported: One patient died, one is disabled, and two healed uneventfully. As a result, we recommend securing heavy soda vending machines to prevent further injuries. To our knowledge, this is the first report on a mechanism of injury resulting from soda machines.

Sensitive radiometric assay for chloramphenicol acetyltransferase using automated HPLC.

Chloramphenicol acetyltransferase (CAT) is widely used as a reporter element in studies of eukaryotic gene expression. We report a new technique for measurement of CAT activity that incorporates several advantages over the existing procedures from which it is derived. The combination of direct reverse-phase HPLC analysis, substitution of butyryl for acetyl coenzyme A substrate, automated sample loading and continuous on-line radioactivity detection significantly improves the assay. This technique eliminates the need for organic extraction; improves chromatographic resolution of radioactive substrate and products; provides low background with high sensitivity, linearity, and precision; and yields rapid, quantitative results, even at low levels of cellular CAT expression.