Jiro Machida

Use of real-time polymerase chain reaction for the diagnosis of infection and differentiation between gram-positive and gram-negative septic arthritis in children.

Background: Diagnosis and identification of the etiological agent of septic arthritis (SA) in children is an important issue, as early treatment based on accurate diagnosis of joint infections can prevent potentially disabling complications. The purpose of this study was to evaluate the efficacy of real-time polymerase chain reaction (PCR) for the diagnosis of SA in children. Patients and Methods: Twenty children with suspected SA who had joint pain and underwent surgical treatment were enrolled in this study. Their preoperative clinical and laboratory findings were investigated. Tissues obtained during operation were subjected to microbiological culture and real-time PCR, including methicillin-resistant Staphylococcus (MRS)-specific PCR and broad range universal PCR. Infection was confirmed if the result of microbiological culture was positive. Furthermore, abnormal clinical and laboratory findings and improvement in the symptoms and posttreatment data were also defined as the final diagnosis of infection. Results: Out of the 20 patients, 19 were diagnosed with the infection. The remaining patient was postoperatively diagnosed with juvenile idiopathic arthritis. Abnormal preoperative body temperatures, white blood cell counts, C-reactive protein levels, and erythrocyte sedimentation rates were observed in 6, 9, 15, and 12 cases, respectively. The results of microbiological culture, MRS-PCR, and universal PCR were positive in 9, 2, and 15 cases, respectively. Analysis of the melting peak in universal PCR revealed that of the 15 cases, 10 had gram-positive and 5 had gram-negative infections. The sensitivity and specificity for the diagnosis of SA were, respectively, 0.47 and 1.00 in microbiological culture and 0.79 and 1.00 in real-time PCR. Conclusions: Successful diagnosis of infection and differentiation between gram-positive and gram-negative bacteria were achieved using MRS-PCR and universal PCR. Hence, real-time PCR is useful and has greater sensitivity than microbial culture for diagnosing SA in children. Level of Evidence: Level II diagnostic study investigating a diagnostic test.

Highly activated matrix metalloproteinase-2 secreted from clones of metastatic lung nodules of nude mice injected with human fibrosarcoma HT1080

The promoting effects of matrix metalloproteinase-2 (MMP-2) on lung metastasis of human fibrosarcoma cells (HT1080) were studied using nude mice. The fourth generation of HT1080 was established by consecutive clonal selection of metastatic lung nodules formed by intravenous transplantation. MMP-2 and MMP-9 in the culture supernatants of the first and fourth generation cells were analyzed by gelatin zymography and Western blotting, and quantified by scanning densitometry. In gelatin zymograms, mean ratios of values for the 59-kDa band (the active form of MMP-2) to those for the 72-kDa band (the inactive form of MMP-2) for optical density; area, and volume measured by densitometry were 1.44 +/- 0.12, 0.93 +/- 0.05, and 1.27 +/- 0.20, respectively, in the culture supernatant of fourth generation cells isolated from metastatic lung nodules. These values were significantly (P < 0.01) higher than those of first generation cells (0.70 +/- 0.04, 0.48 +/- 0.01, and 0.57 +/- 0.42). Three weeks after intravenous transplantation of HT1080 cells into nude mice, the incidence of lung metastasis and mean number and diameter of metastatic nodules formed by injection of first generation cells were 20% (2 of 10 mice), 2.9 +/- 0.2 and 2.0 +/- 0.2 mm, respectively; while they were 100%, 99.8 +/- 7.2 and 4.3 +/- 0.3 mm following injection of fourth generation cells. These findings suggest that the active MMP-2 produced by human fibrosarcoma cells is important for the cells to form lung metastatic lesions in nude mice.

Flexibility of idiopathic congenital clubfeet treated by posteromedial release without talocalcaneal joint release.

We retrospectively reviewed 57 patients with 84 idiopathic clubfeet and followed them up for at least 15 years. All feet were rated as good or excellent according to the International Clubfoot Study Group score. Stress radiographs showed that the arc of forefoot motion of conservatively treated feet was 81%, in operated feet of patients aged more than 1 year it was 74%, and in feet of patients aged less than 1 year during surgery it was 65%, compared with those in contralateral normal feet. Despite the severity of the deformity, feet treated by our posteromedial release without talocalcaneal joint release were flexible and functional.

Use of dynamic spinal brace in the management of neuromuscular scoliosis: a preliminary report.

Neuromuscular scoliosis is difficult to treat with braces because the collapsing trunk with the spinal deformity cannot tolerate the hard materials used for most orthoses. The dynamic spinal brace (DSB) is a novel three-point support brace used in Japan. We present our preliminary findings of 52 pediatric patients with neuromuscular scoliosis treated using DSBs. A positive correlation was found between the Cobb angle at the initiation of bracing and the degree of scoliosis progression. We concluded that DSBs may be effective for early-stage scoliosis. We also found that DSB improved sitting stability and thereby caregiver satisfaction.

Rotational open-wedge osteotomy improves treatment outcomes for patients older than eight years with Legg-Calve-Perthes disease in the modified lateral pillar B/C border or C group

PurposeSince 2003, we have been performing rotational open-wedge osteotomy (ROWO) for older children with severe Legg-Calve-Perthes disease (LCPD). We compared the treatment outcomes before and after the introduction of ROWO for patients aged ≥ eight years, classified in the modified lateral pillar B/C border or C group.MethodsBefore the introduction of ROWO, conservative treatment (non-weight bearing [NWB]) was performed for all cases between 1986 and 2002, whereby there were 34 hips (NWB group). The median patient age, at the first visit, was 9.1 years. According to the lateral pillar classification, 21 hips were categorized into the B/C border group and the others into the C group. Meanwhile, 14 consecutive hips underwent ROWO combined with NWB between 2003 and 2008 (ROWO+NWB group). The median patient age, at the first visit, was 9.1 years. Six hips were in the lateral pillar B/C border group and the others were classified into the C group. There were no significant differences in pre-treatment patients’ demographic data.ResultsAt the latest follow-up, according to the Stulberg classification, there were 19 class II hips, 13 class III hips, and two class IV hips in the NWB group. In the ROWO+NWB group, there were 12 class II hips, two class III hips, and no class IV hips.ConclusionsThe application of ROWO combined with NWB in the treatment of older children with severe LCPD improved their outcomes, compared to those obtained by NWB treatment alone.

Novel 2 Radiographical Measurements for Atlantoaxial Instability in Children With Down Syndrome

Study Design. A retrospective case-control study. Objective. To assess the usefulness and reproducibility of 2 novel safe and simple radiographical measurements for atlantoaxial instability in children with Down syndrome. Summary of Background Data. In pediatric atlantoaxial instability, early diagnosis is important for improved outcomes because of poor postoperative recovery in progressed neurological symptoms. Conventional dynamic radiography of the cervical spine is associated with a potential risk of worsening neurological symptoms. Methods. We retrospectively reviewed the medical records of 50 patients (24 boys and 26 girls) with atlantoaxial instability associated with Down syndrome. Of the 50 children, 11 had undergone and 4 had been scheduled for surgery (surgical group). In this investigation, in addition to the atlas-dens interval (ADI) and space available for spinal cord (SAC), we measured C1 inclination angle and C1/4 SAC ratio on lateral radiographs of the cervical spine in the neutral position. To assess the diagnostic abilities of these indices to determine indication for surgery, receiver operating characteristic analysis of each index was performed, and their diagnostic abilities were compared using the area under the receiver operating characteristic curve. Moreover, we assessed reproducibility of our 2 proposed indices. Results. The discriminatory abilities of C1/4 SAC ratio (area under the receiver operating characteristic curve, 1.00) and C1 inclination angle (0.91) were comparable with those of ADI (0.98) and SAC (0.95). For the interobserver and intraobserver reliability of the novel indices, the correlation coefficients were in the range from 0.88 to 0.99. Correlation was observed between the ADI and C1/4 SAC ratio (r = 0.507, P < 0.01) and between the ADI and C1 inclination angle (r = 0.407, P < 0.01). Conclusion. The diagnostic abilities of the 2 novel radiographical measurements were comparable with those of ADI and SAC. Moreover, these novel measurements can be obtained safely on lateral radiographs of the cervical spine in the neutral position. Level of Evidence: 4

Bone metabolism and inflammatory characteristics in 14 cases of chronic nonbacterial osteomyelitis

BackgroundChronic nonbacterial osteomyelitis (CNO) is a multifocal autoinflammatory disease that often impairs daily life in children. This study aimed to investigate the bone metabolic and inflammatory characteristics of patients with CNO, and to assess the differences between responders and nonresponders to conservative treatment.MethodsWe investigated the clinical symptoms; laboratory data including inflammatory and bone metabolic biomarkers; and imaging findings from plain radiography, magnetic resonance imaging (MRI), fluorodeoxyglucose-positron emission tomography (FDG-PET), and dual-energy x-ray absorption (DEXA) in 14 patients with CNO. All patients underwent first-line treatment comprising systemic nonsteroidal anti-inflammatory drugs with or without bisphosphonate. According to the response to the first-line treatment, the patients were divided into the clinical remission/partial response group and the no response group. The differences in bone metabolic and inflammatory characteristics between the two groups were assessed.ResultsAll patients had low bone mineral density assessed with DEXA. The bone metabolic biomarkers (bone-specific alkaline phosphatase and tartrate-resistant acid phosphatase 5b) were increased in boys of all ages and in young girls. Multiple inflammatory regions were detected in all patients by using FDG-PET including asymptomatic regions. The no response group had higher immunoglobulin G (IgG) and a greater number of bone inflammatory lesions detected on MRI than the clinical remission/partial response group.ConclusionOur data indicate the involvement of abnormal bone turnover, necessity of whole-body scanning, and association of higher serum IgG levels and greater numbers of inflammatory lesions with prolonged disease activity in patients with CNO.

Management of foot deformity in children

This study describes the management of foot deformity in children. Severe congenital clubfeet treated using posteromedial release without talocalcaneal joint release were flexible and functional. Talectomy may be necessary for congenital clubfeet with arthrogryposis multiplex congenita. The diagnosis and severity of vertical talus were defined based on stress radiographs. For the deformity with spina bifida, a combination of talocalcaneal joint fusion and precise correction by soft tissue release and tendon transfer was performed. This combined surgery is effective, particularly in patients with equino-varus feet.

Use of glenoid inclination angle for the assessment of unilateral congenital high scapula.

Little has been reported on the motion of the scapula in Sprengel’s deformity. Fourteen patients with unilateral congenital high scapula underwent the Woodward procedure from 1986 to 2004. The median age of the patients at the time of surgery was 4.4 years and the median follow-up duration was 8.8 years. The range of motion of the shoulder and the glenoid inclination angle (GIA) were measured preoperatively and at the final visit. The range of motion of the shoulder and GIA improved at the final visit. There was a positive correlation between the maximum abduction angle of the upper limb and GIA at the final visit.

Giant cell tumour of the femur in a 9-year-old girl, resulting in severe leg length discrepancy.

Giant cell tumour of bone (GCTB) is a rare benign tumour noted before physeal closure. GCTB cases in patients younger than 10 years are especially uncommon. The authors report the case of a 9-year-old girl with a GCTB of the distal femur. After initial intralesional excision and curettage of the tumour, local recurrence occurred, which needed two more additional surgeries to treat. The primary tumour and the local relapse invaded the growth plate of the right distal femur, leading to growth disturbance of the femur and requiring leg lengthening using Ilizarov apparatus. Surgeons should note the possibility of this rare condition while treating radiographic lytic lesions even in skeletally immature patients. The occurrence of late limb length discrepancy would be more likely in younger patients.