HISTOCHEMICAL DEMONSTRATION OF PHOSPHOLIPASE B (LYSOLECITHINASE) ACTIVITY IN RAT TISSUES

A method has been developed for the histochemical demonstration of phospholipase B (lysolecithinase) of rat tissues. The enzyme attacks lysolecithin with liberation of 1 mole of glycerylphosphorylcholine and 1 mole of fatty acid. The recommended procedure involves use of 6-10 µ frozen sections, fixed in cold calcium-formol and incubated at 37°C in Tris buffered medium at pH 6.6 containing 2.2 x 10–3 M lysolecithin and 1% cobalt acetate. The fatty acid liberated by enzymatic hydrolysis is trapped as a cobalt precipitate and is then converted to a blackbrown precipitate by treatment with dilute ammonium sulfide in cold isotonic saline. Equivalent amounts of fatty acid and glycerylphosphorylcholine are recovered by extraction and analysis of the incubated sections and of the incubation medium, thus proving that lysolecithin hydrolysis occurs under the proposed reaction conditions. Staining is reduced by treating the sections with copper ions, mercury compounds, alcohols, acetone and by heating at 60°C prior to incubation with substrate. Lowering of the pH of the incubation medium has similar effect. These findings are interpreted as evidence of the enzymatic nature of the reaction. Cells exhibiting a positive staining are found in the lamina propria of the intestinal villi and crypts, in the red pulp of the spleen and in the interstitial tissue of lung, liver and thymus. Similar elements are present in bone marrow smears and in leukocyte preparations obtained by peritoneal lavage. The morphologic and staining characteristics of these cells correspond to those of the eosinophilic leukocytes. Physical and chemical agents (x-irradiation corticosteroids) which sharply decrease the number of eosinophils also reduce the number of cells shown histochemically to hydrolyze lysolecithin. A correspondent. diminution of phospholipase B activity of homogenates of the same tissues can be shown in vitro. Differences in tissue distribution and chemical properties distinguish the phospholipase B from less specific esterases and lipases.

Cerebral palsy. Evaluation and management of equinus and equinovarus deformities

Walking function may be enhanced by correcting equinus and equinovarus deformities in CP. Nonoperative management should be used in young children. Muscle balancing procedures, such as gastrocnemius aponeurosis lengthening, Achilles' tendon lengthening, and SPLATT, are particularly useful in correcting these deformities.

A modified technique for insertion of a unit rod into the pelvis

The use of a pedicle probe facilitated insertion of a unit rod into the ilium of five patients with neuromuscular scoliosis. Compared to the standard technique, the pedicle probe method greatly reduced soft-tissue dissection and also provided better perception of rod alignment and cortical perforation.

The role of journal clubs in orthopaedic surgery residency programs

Journal clubs have a long history in graduate medical education; however, their role in orthopaedic surgery residencies has not been analyzed. The 161 orthopaedic residency program directors in the United States and Canada were surveyed to determine the frequency, format, and goals of journal clubs. Journal clubs are a regular part of the education program in 147 of the 149 programs that responded. Most journal clubs meet once per month in the evening and review articles from more than one periodical. Program directors rate teaching residents how to evaluate a scientific article as the most important goal of a journal club. Although journal clubs are virtually universal in orthopaedic programs, additional study is needed to assess their efficacy and optimal format.

The clinical, histologic, and ultrastructural presentation of polyvinyl sponge (Ivalon) breast prostheses removed for massive fluid accumulation

The current study describes what we believe is the first report of bilateral massive seromas associated with open-cell Ivalon sponges. Additionally, the gross, histologic, and ultrastructural features consistent with previous reports of polyvinyl alcohol prostheses are presented. Despite the reported chemical inertness of polyvinyl alcohol, this material may incite a biologic response in some patients, leading to dense fibrosis and occasional foreign-body giant-cell reaction. It is postulated that the molecular breakdown products of the polyvinyl alcohol polymer may create an osmotic gradient across the periprosthetic capsule, which may lead to intracapsular fluid accumulation, as presented in this case.

Elemental analysis and clinical implications of calcification deposits associated with silicone breast implants

Calcification of the fibrous capsule surrounding silicone breast implants is a well-recognized occurrence that increases with time following implantation. These mineralized deposits potentially confound mammographic breast cancer surveillance already made difficult by the obscuring effects of silicone breast implants. The authors performed elemental analysis of silicone breast implant-associated calcifications to define better their chemical composition as related to mammographic and clinical significance. Electron probe microanalysis and infrared spectroscopy revealed all of the calcification deposits to be calcium complexed with tribasic phosphate. No evidence of calcium oxalate, calcium carbonate, silicone, or talc was observed. Caution must be employed in interpreting mammograms in women with silicone breast implants as well as those who have had their silicone breast implants removed. High-density mammographic calcifications indicative of calcium phosphate associated with a silicone breast implant may represent an accepted consequence of implantation or nearby carcinoma. We recommend baseline mammography on women who have had their silicone breast implants removed to prevent unnecessary fine-needle aspiration or tissue biopsy of retained breast capsule calcifications during subsequent routine surveillance for carcinoma.

Closed treatment of hip dislocation in Down syndrome

Two young children (three hips) with Down syndrome and dislocation of the hip were successfully treated by nonoperative methods by using the principle of prolonged immobilization or bracing. A 5-year, 6-month-old patient with bilateral habitual dislocation used an ambulatory abduction orthosis full-time for 6 months and then part-time for 4 months. Complete dislocation of the right hip in a 4-year, 6-month-old patient was managed by closed reduction, spica cast immobilization for 4 months, and then an ambulatory abduction orthosis for 8 months. Both patients developed stable, well-contained hips. Nonoperative management of hip dislocation in Down syndrome can be successful and avoids the complications associated with operations previously recommended for these patients.

Displaced fractures of the femoral shaft in children. Unique features and therapeutic options

The decision analysis for managing femoral shaft fractures in children should included such factors as the possibility of child abuse, overgrowth, and the potential for remodeling. Direct and indirect costs must be understood. Factors to consider in determining treatment include the age of the child, the extent of the soft tissue injury, and associated injuries. Non-operative methods, universally used in the past to treat these injuries, still are indicated, but operative modalities should be considered for a greater number of pediatric femoral fractures. Early enthusiasm for external fixation and rigid intramedullary rodding has been tempered by a greater awareness of their particular complications. The role of flexible intramedullary rodding, however, is expanding.

Morphology and pathogenesis of Liesegang rings in cyst aspirates: report of two cases with ancillary studies

Liesegang rings are laminated ring-like structures occasionally found in benign cysts and abscesses. They have been confused with parasites (especially eggs), algae, calcifications, and psammoma bodies. We examined Liesegang rings from fine-needle aspiration (FNA) biopsies of a benign cyst of the breast and a complex renal cyst. Liesegang rings were best observed with Papanicolaou, hematoxylin-eosin, Masson's trichrome, acid-fast (AFB), and Gram stains, which accentuate the concentrically laminated morphology. An amorphous electron-dense core and fibrillary lucent concentric rings were seen with transmission electron microscopy with no significant energy peaks by electron probe microanalysis or distinct diffraction patterns by X-ray diffraction. This investigation indicates that Liesegang rings are composed of organic substances most likely formed by periodic precipitation from a supersaturated solution within cystic fluid. Awareness of the Liesegang phenomenon within cystic lesions will decrease the possibility of erroneous misdiagnosis as another type of pathologic process.

Prophylactic transfusion for hypertrophic synovitis in children with hemophilia

A 7- to 9-month protocol of prophylactic transfusion was used to treat 33 joints in 19 children with severe hemophilia (< 1 U/dL Factors VIII or IX) and hypertrophic synovitis. The overall rate of hemarthrosis was reduced, but only 36% (12 of 33 joints) achieved a good result (defined as 0-0.5 bleeding episodes per month and decreased synovial hypertrophy 1 year after completing treatment). Age and severity of arthropathy at initiation of treatment did not affect the result. The degree of synovial hypertrophy and involvement of the knee joint showed an adverse trend, but these factors did not achieve statistical significance. The number of episodes of breakthrough bleeding during the first 6 weeks of therapy was significantly associated with a poor result. Based on the results of this study, a trial of transfusion therapy is recommended for recurrent hemarthroses and synovitis in patients with hemophilia, but the duration of thrice weekly treatment has been increased and the duration of prophylaxis has been reduced in selected cases.

Respiratory reovirus 1/L induction of intraluminal fibrosis. A model for the study of bronchiolitis obliterans organizing pneumonia

Bronchiolitis obliterans organizing pneumonia (BOOP) is a term that was first applied in 1985 to describe a long-observed but unclassified pattern of acute lung injury. BOOP lesions are characterized by fibrous extensions into the alveolar spaces in association with a peribronchiolar organizing pneumonia. Since 1985, an increasing number of reports of BOOP have appeared in the clinical literature, and it is now accepted that BOOP is a significant pulmonary syndrome. Although BOOP can be associated with a number of documented pulmonary insults, many cases are not associated with known causes and are thus classified as idiopathic. The lack of an appropriate small animal model that closely mimics the generation of BOOP lesions has been an impediment to basic studies of the pathogenic mechanisms responsible for the generation of BOOP in humans. In this report, we describe an animal model for BOOP in which CBA/J mice infected with reovirus serotype 1/strain Lang develop BOOP lesions. These lesions closely resemble those seen in humans and occur in a well defined temporal sequence that proceeds from initial peribronchiolar inflammatory lesions to characteristic, fibrotic cellular BOOP lesions over a 3-week time course.

Silicone breast implants: pathology

Questions as to the bioreactivity of silicone breast implants (SBIs) have recently been intensely scrutinized, most notably by the media and legal system. Pathologists must be aware of the controversy and treat each SBI and associated tissue as a potential lawsuit. Grossly, silicone is a clear, viscous substance that may be observed either within or extruding from a silastic bag. By light microscopy, silicone is a nonstainable, nonpolarizable, refractile substance. Thicker sections, especially when viewed by non-Köhler illumination, phase-contrast, and darkfield microscopy will enhance visualization. Ultrastructurally, silicone is an electron-dense, amorphous substance often located within phagocytic vacuoles or extracellularly within the stroma. Correlating electron probe microanalysis allows for reliable identification. In most cases, a fibrous capsule surrounds the SBI, with the interface lining varying from a virtually acellular to a synovial-like lining composed of phagocytic and secretory cells. Silicone can often be identified within the fibrous capsule and also in distant tissues biopsied for suspected autoimmune disorders, such as synovium, skin, and lymph nodes, often without ultrastructural evidence of cytologic effects. This study has demonstrated that silicone accumulates at distant tissue sites due to preexisting inflammation acting as a stimulus. Thus, silicone is not a primary inducer of inflammatory disease processes. These findings are supported by various large epidemiologic studies.

Crystallizing galactocele. A case report

BACKGROUND

Galactoceles are benign cystic lesions that generally occur during pregnancy and postpartum lactation. Fine needle aspiration (FNA) yields milky fluid that is often both diagnostic and therapeutic. Cytologically, aspirates are generally noted to contain occasional foam cells and benign epithelium displaying lactational change with an abundant background of lipid micelles and proteinaceous material.

CASE

A 23-year-old, black female presented with a 1.0-cm, discrete, nontender nodule involving the upper middle area of the left breast. FNA showed crystals of varying size and shape, best viewed with Diff-Quik and demonstrating metachromasia, polarization and birefringence. They were also positive with periodic acid-Schiff stain and both alizarin red S and von Kossa stain for calcium. Scanning electron microscopy revealed angulated, well-defined geometric crystals often with scalloped edges and smooth surfaces. The internal structure of the crystals consisted of electron-lucent material without periodicity or lattice formation, as observed by transmission electron microscopy and x-ray diffraction. Electron probe microanalysis identified small quantities of calcium, chlorine, potassium and sulphur within the crystals.

CONCLUSION

We think that in this case the crystals represented precipitation of inspissated lactational secretions. There are several possible mechanisms of precipitation. The differential diagnosis includes other breast lesions with acellular amorphous components that may be confused with crystallizing galactocele in FNA biopsy specimens.

Silicone deposition in reconstruction scars of women with silicone breast implants

BACKGROUND

The possible association of silicone breast implants and disease is a subject of continuous debate and concern.

OBJECTIVE

Our purpose was to examine microscopically and ultrastructurally the periprosthetic fibrous capsules and reconstruction scars of women with silicone breast implants.

METHODS

Representative samples from the periprosthetic capsules and reconstruction scars from six women with silicone breast implants were examined by a variety of light microscopy techniques, transmission electron microscopy, and electron probe microanalysis.

RESULTS

Silicone globules of various sizes were identified in every periprosthetic capsule and reconstruction scar.

CONCLUSION

Extrusion and seeding of the incision tract during surgery most likely accounts for the presence of silicone in the reconstruction scar specimens. This observation suggests that the identification of silicone in the reconstruction scars of women with silicone breast implants does not necessarily implicate rupture of the silicone breast implant with systemic dissemination of silicone gel.

Caterpillar bodies of porphyria cutanea tarda ultrastructurally represent a unique arrangement of colloid and basement membrane bodies

Caterpillar bodies are eosinophilic, periodic acid-Schiff (PAS)-positive globules arranged in a linear fashion in the epidermis overlying subepidermal blisters of porphyria cutanea tarda (Am J Dermatopathol 1993;15:199-202). We retrospectively studied by transmission electron microscopy nine cases of porphyria cutanea tarda (PCT) that demonstrated caterpillar bodies. We identified three components of the eosinophilic bodies: degenerating keratinocytes, colloid bodies, and basement membrane bodies. The colloid bodies consisted of whorled masses of filaments containing degenerating melanosomes, vacuoles, mitochondria, and desmosomes. Basement membrane bodies were composed of convoluted basement membrane material and associated collagen. Both colloid and basement membrane bodies were often associated with degenerating keratinocytes, were located both intra-and extracellularly, and were occasionally fused to one another. We believe that caterpillar bodies are a combination of degenerating keratinocytes, colloid bodies, and basement membrane bodies formed by repeated blistering and reepithelialization with transepidermal migration. Furthermore, we believe that caterpillar bodies are a diagnostic clue for the diagnosis of PCT.

Bone-mineral density in children and adolescents who have spastic cerebral palsy

Bone-mineral density was studied in a heterogeneous group of 139 children (mean age, nine years; range, three to fifteen years) who had spastic cerebral palsy. The evaluation included serum analyses and a nutritional assessment based on a dietary history and anthropometric measurements. The bone-mineral density of the proximal parts of the femora and the lumbar spine was measured with dual-energy x-ray absorptiometry and was normalized for age against a series of ninety-five normal children and adolescents who served as controls. Bone-mineral density varied greatly but averaged nearly one standard deviation below the age-matched normal means for both the proximal parts of the femora (-0.92 standard deviation) and the lumbar spine (-0.80 standard deviation). Ambulatory status was the factor that best correlated with bone-mineral density. Nutritional status, assessed on the basis of caloric intake, skinfolds, and body-mass index, was the second most significant variable. The pattern of involvement, durations of immobilization in a cast, and a calcium intake of less than 500 milligrams per day were additional factors of less significance. The age when the child first walked, previous fractures, use of anticonvulsants, and serum vitamin-D levels did not correlate with bone-mineral density after adjustment for covariance with the ambulatory status and the nutritional status. Serum levels of calcium, phosphate, alkaline phosphatase, and osteocalcin were not reliable indicators of low bone-mineral density.

Synovial metaplasia of a periprosthetic capsule surrounding a polyurethane foam breast prosthesis

A 43-year-old woman underwent two-stage bilateral reconstruction mammoplasty using silicone-filled, polyurethane foam-covered breast implants. The permanent implants were later removed. The periprosthetic capsule demonstrated synovial metaplasia by light and electron microscopy. Synovial metaplasia is believed to be induced by the physical and chemical characteristics of the prostheses and may have important clinical implications in reducing capsular contracture and increasing host acceptance of implantable biomaterials.

Electron probe microanalysis of silicon and the role of the macrophage in proximal (capsule) and distant sites in augmentation mammaplasty patients

Electron probe x-ray microanalysis was used to locate silicon (Si) within macrophages from 12 women who had previously undergone polymer prosthesis augmentation or reconstruction. Silicon was identified within macrophages and extracellularly in all fibrous breast capsules. In four women with arthritic joint pain and one woman with sclerodermatous skin lesions, silicon also was identified within macrophages residing in joint synovium and skin, respectively. It is suggested that the silicon-laden macrophages observed in the remote lesions may have accumulated silicon from other macrophages that had previously resided in the connective-tissue capsule around the silicone breast implants.

Light microscopy techniques for the demonstration of silicone gel

Because of the difficulty in identifying silicone gel in histologic and cytologic specimens by means of conventional light microscopy, we investigated alternative light microscopy techniques, as well as specimen staining and preparation. Specimens from six periprosthetic capsules, one silicone granuloma specimen, and one synovial biopsy specimen obtained from women with silicone breast implants were cut at 4-, 10-, 20-, and 30-microns sections, stained with a variety of common stains, and correlated with electron probe microanalysis. In addition, a commercial silicone gel and silicone gel extracted from a previously implanted silicone breast prosthesis were smeared and examined unstained or stained with Papanicolaou and Diff Quik. Silicone was noted to be refractile, nonpolarizable, and nonstainable. Thicker sections prevented silicone "dropout" during processing and increased the contrast between stained tissue and unstained silicone (negative staining). The relative ease of silicone identification was greatly increased with non-Koehler, phase contrast, and darkfield microscopy. Staining the mounting media of hematoxylin-eosin-stained sections with a nonparticulate commercial ink allowed enhanced negative staining detection of silicone gel.

Synovectomy of the ankle for hemophilic arthropathy

The results of five patients who had hemophilia and a history of recurrent hemarthrosis and hypertrophic synovitis and who had been managed with a synovectomy of the ankle were studied at an average age of nine years (range, four years and seven months to nineteen years). Compared with the complications encountered after synovectomy of the knee or the elbow, the rehabilitation process after synovectomy of the ankle was relatively easy, even for the three youngest children in this series. The average duration of follow-up was five years (range, one to nine years). By the latest follow-up examination, the range of motion of the ankle had increased an average of 10 degrees (range, -5 to 15 degrees). The rate of hemarthrosis episodes requiring transfusion was reduced from an average of 3.4 per month (range, 0.3 to 5.0 per month) for the six months before the synovectomy to 0.1 per month (range, zero to 0.2 per month) for the twelve months before the latest follow-up examination.

Etiology of late-onset tibia vara: is varus alignment a prerequisite?

One widely held theory on the pathogenesis of adolescent late-onset tibia vara is that obesity coupled with mild preexisting varus alignment produces forces sufficient to retard growth in the medial portion of the proximal tibial physis and initiates the development of the condition. Two cases are presented in which neutral mechanical alignment was clearly documented in an extremity that subsequently developed adolescent late-onset tibia vara within 19 months. We conclude that in at least some cases, preexisting varus alignment is not a prerequisite for the development of adolescent late-onset tibia vara.

Synovial metaplasia of a periprosthetic breast capsule

A 48-year-old woman presented for reconstruction mammoplasty 5 years after undergoing a mastectomy for breast carcinoma. She underwent tissue expansion, with subsequent placement of a permanent silicone implant, removal of the permanent implant because of asymmetry, and further tissue expansion for another attempt at permanent silicone implant placement. The periprosthetic breast capsule surrounding the initial permanent implant consisted of a lining intima, subintima, and fibrous capsule consistent with synovium on light microscopy, immunohistochemical studies, transmission electron microscopy, and scanning electron microscopy. Silicone was localized intracellularly within the lining cells and extracellularly within the fibrous capsule by electron probe microanalysis. We believe that this case represents synovial metaplasia of a periprosthetic breast capsule that was most likely induced by repeated manipulation and silicon exposure from silicone gel leakage and the prosthetic Silastic shell.

Genu varum and genu valgum in children

Genu varum and genu valgum are often normal developmental changes in knee alignment that occur in a young child. Measuring the child's height and understanding normal development is the key to determining which children need further evaluation for a possible skeletal or metabolic bone dysplasia.

Acrosyndactyly with epidermoid inclusion cysts: evidence for the extrinsic theory

A case of acrosyndactyly was treated with routine syndactyly release and full-thickness skin grafts. Two epidermoid inclusion cysts were found within the syndactylyzed index and middle fingers. This association is discussed along with the mechanism that best explains this unusual occurrence.

One-stage release of congenital circumferential constriction bands

A one-stage release of circumferential congenital constriction bands was performed in four extremities (three patients). No wound problems occurred, even when there had been marked swelling of the extremity distal to the band. The one-stage release facilitated postoperative care, and there was no need for additional periods of anesthesia or for additional operations, which are necessary when this problem is treated with a release performed in two or three stages.

Endoscopic treatment of reflux: migration of Teflon to the lungs and brain

We set out to determine experimentally whether particles of polytetrafluoroethylene migrate to the lungs and brain when relatively small volumes of Teflon paste are injected into the bladder in the manner used to correct reflux. Numerous particles of polytetrafluoroethylene were recovered from these organs within 2 weeks of injection. Those in the brain measured up to 15 microns in diameter, indicating that the pulmonary bed is an inefficient filter of particles gaining access to the venous circulation. Although clinically no adverse neurological effects have hitherto been reported, this study suggests that following the 'sting' procedure, some particles may lodge in the brain where they can block the cerebral microcirculation. We believe these findings represent a contraindication to the use of Teflon paste in children.

Transfer versus lengthening of the posterior tibial tendon in Duchenne's muscular dystrophy

Transfer of the posterior tibialis tendon to the dorsum of the foot was compared with lengthening of this tendon in 15 patients with Duchenne's muscular dystrophy. Patients undergoing tendon transfer (N = 9) had a longer operating time and two perioperative complications, but retained plantigrade posture of their feet even after walking ceased. By contrast, lengthening of the posterior tibialis tendon (N = 6) was associated with a recurrent equinovarus foot deformity that frequently interfered with shoe wear. Although transfer of the posterior tibialis is out of phase and technically more demanding, the unique prolongation of posterior tibialis strength in Duchenne's muscular dystrophy makes this operation a better option for these patients.

Displaced supracondylar humeral fractures in children. A comparison of results and costs in patients treated by skeletal traction versus percutaneous pinning

Clinical outcome and treatment cost were compared in 65 children treated by either percutaneous pinning or skeletal traction for displaced supracondylar humeral fractures. Clinical outcome was evaluated by loss of elbow motion and change in carrying angle. Results of treatment were basically equivalent in the two groups and were satisfactory in 90% or more. To determine treatment cost, the authors analyzed factors that vary according to the type of therapy. Cost of treatment was lowest in those who had percutaneous pinning and subsequent pin removal in the office. Compared to this group, the cost of treatment increased by 23% in those who had percutaneous pinning and removal of the pins as a surgical procedure, by 117% in those treated by traction with the olecranon pin inserted in the emergency room, and by 142% in those treated by traction with the olecranon pin inserted in the operating room.

An improved cryo-jet freezing method

A new cryo-jet freezing apparatus is described that is easy to use and gives good results using a propane-butene mixture (3:1). Our use of the freezer in the study of mouse spinal cord explant cultures is discussed. At the tissue surface, the quality of tissue preservation from freezing, followed by freeze substitution, rivals that of conventional electron microscopic methods. Certain intracellular structures are better visualized using our methods. There is no evidence of the tissue being distorted by the cryogen jet when the freezer is operated correctly. A new freeze substitution device is also discussed.

Adolescent tibia vara: alternatives for operative treatment

We reviewed the cases of fifteen obese patients (twenty-one extremities) who had had adolescent tibia vara and had been followed for at least two years. Of the nine patients (eleven extremities) who had been initially managed with lateral tibial hemiepiphyseodesis, eight (ten extremities) were skeletally mature at the time of the review (mean duration of follow-up, five years). The mechanical alignment was judged to be excellent in three of these ten extremities, fair in three, and poor in four. Excellent mechanical alignment was defined as a value within the reported normal range of 5 degrees of varus to 2 degrees of valgus. A poor result was defined as alignment that was more than 5 degrees outside the normal range. After secondary operative procedures, three of the extremities for which the result had been poor and one for which it had been fair had excellent alignment. Five of the nine patients had bilateral involvement. Two of them were managed with bilateral tibial hemiepiphyseodesis; two, with contralateral proximal tibial osteotomy; and one had a mild deformity on the contralateral side that was not treated. Six extremities in six patients (two of whom had a contralateral hemiepiphyseodesis) were managed primarily with proximal tibial osteotomy and were evaluated an average of seven years postoperatively. Two additional patients were managed with proximal tibial osteotomy because of residual varus deformity after the hemiepiphyseodesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Rapid progression of hip subluxation in cerebral palsy after selective posterior rhizotomy

Rapid progression of hip subluxation was noted in the year after selective dorsal rhizotomy in seven hips (six patients). The hips that subluxed progressed from a lateral extrusion index averaging 25% preoperatively as compared with 50% after rhizotomy. Although preexistent hip dysplasia was a predisposing factor, hips with an intermediate degree of preoperative lateral extrusion (12-25%) had variable results. Ongoing and more frequent evaluation of hip stability is necessary after dorsal rhizotomy.

Vertebral Candida infections. A case report and review of the literature

Vertebral Candida infection in a 57-year-old woman became symptomatic three months following Candida septicemia associated with a central venous catheter. The infection was successfully treated with amphotericin B and ketoconazole. Review of the literature revealed 29 cases of Candida infection with vertebral involvement. Intravenous drug abuse and central venous catheters were identified as predisposing factors in 13 cases. An average delay from Candida septicemia until the time the patient sought treatment was 3.3 months. Antifungal agents generally resulted in resolution of the infection.

Osteomyelitis of the patella in children

The early diagnosis of osteomyelitis of the patella in children can be difficult due to the rarity of this infection and to the vagaries of presentation which may be either acute with systemic signs or insidious with mild local signs. We present four cases of patellar osteomyelitis to illustrate the spectrum of this disorder. There should be a high index of suspicion with persistent pain and swelling above the knee, septic prepatellar bursitis, and septic knees that do not respond to conventional management. Management parallels treatment of osteomyelitis of other bones.

Musculoskeletal problems in association with cloacal exstrophy

The records of all thirteen patients for whom a diagnosis of cloacal exstrophy had been recorded in our hospitals were analyzed for evidence of musculoskeletal problems. All thirteen patients had spina bifida, four had congenital scoliosis, two had congenital kyphosis, and three had non-congenital scoliosis. All had a lipomeningocele, and eleven had paralysis of the lower extremities. Hydrocephalus and its associated problems were not found, but tethered-cord syndrome was diagnosed in eleven patients. Persistent diastasis of the symphysis pubis was found in all patients. Abduction and external rotation of the hips were more than normal. Mild dysplasia was seen in six of the twenty-six hips. Deformities of the foot were common, and twelve feet had been operated on for correction. Recurrent equinovarus deformity of the foot was associated with tethered-cord syndrome in two patients.

Effect of race and gender on neurological level in myelomeningocele

The association of race and gender with different neurological levels of myelomeningocele was studied in 251 patients. Over-all, the white to black ratio was 3.6 and the male to female ratio was 0.86. However, the proportions of whites and females were significantly increased in thoracic-level patients (white to black ratio 13.6, male to female ratio 0.43), whereas the lumbar-level patients had sex and white to black ratios equivalent to the area population. This supports the concept that thoracic-level myelomeningocele has a different pathogenesis from lumbar-level.

Variability in radiographic measurement of bowleg deformity in children

The tibial metaphyseal-diaphyseal (MD) and tibial-femoral (TF) angles were measured on the radiographs of 33 knees in young children (aged 12-36 months) with bowleg deformity. Four observers of differing experience measured the films in a blinded fashion to determine the intraobserver and interobserver variability of these measurements. The clinical implications of these variabilities are described. Very little instruction and experience is necessary to make these measurements correctly and precisely. Measurement of the MD angle was superior to measurement of the TF angle. Contrary to published opinion, rotation can have a small but potentially significant effect on the measured MD angle.

Evaluation of magnetic resonance imaging in Legg-Perthes disease: a prospective, blinded study

Twenty-two patients (24 hips) with Legg-Perthes disease received 49 magnetic resonance (MRI) scans. The scans and corresponding radiographs were independently evaluated in a blinded fashion to assess the capabilities of, and indications for, MRI in Legg-Perthes disease. Early in the disease process, MRI often more clearly delineated the extent and location of areas of involvement than did plain radiographs. In one patient, MRI failed to indicate necrosis early in the course of the disease, but it was detected on plain radiographs. MRI can also be used to give a rough estimate of sphericity, which in some phases of the disease process is better than plain radiographs. For serially following the disease process through the natural healing course, plain radiographs were as good or better than MRI and considerably less costly.

Orthopaedic procedures and prognosis in hemophilic patients who are seropositive for human immunodeficiency virus

Thirty patients who had hemophilia and were seropositive for the human immunodeficiency virus were evaluated. The preoperative CD4 lymphocyte count was decreased to an average of 336 x 10(9) per liter (range, 27 to 708 x 10(9) per liter). After twenty-six orthopaedic operations in patients who had no previous bacterial infection, a nosocomial infection (cellulitis in the forearm, at the site of an intravenous catheter) developed in only one patient, but five patients had an abnormal postoperative fever that was not accompanied by the expected increase in the white blood-cell count. The preoperative CD4 lymphocyte count was significantly reduced in the patients who had an abnormal elevation in body temperature (p less than 0.004). The functional result or outcome after operation was similar to that in hemophilic patients treated before 1982. Subsequent progression of infection with the human immunodeficiency virus, as determined by the CD4 lymphocyte count and the Walter Reed classification system, occurred in most patients. Acquired immunodeficiency syndrome was diagnosed in six patients. A more rapid progression to acquired immunodeficiency syndrome was seen in the patients who had a lower CD4 lymphocyte count preoperatively. Preoperative evaluation of the CD4 lymphocyte count and the response to intradermal skin-test antigens in patients who are at risk for infection postoperatively provides additional information concerning immunological competence. With these data, the possible risk of infection in patients who are seropositive for the human immunodeficiency virus can be estimated more accurately.