Jérôme Berard

Specific real-time polymerase chain reaction places Kingella kingae as the most common cause of osteoarticular infections in young children.

Background: The use of universal 16S rDNA polymerase chain reaction (PCR) has recently shown that the place of Kingella kingae in osteoarticular infections (OAI) in young children has been underestimated, but this technique is not the most sensitive or the most rapid method for molecular diagnosis. We developed a specific real-time PCR method to detect K. kingae DNA and applied it to the etiologic diagnosis of OAI. Patients and Methods: All children admitted to a pediatric unit for OAI between January 2004 and December 2005 were enrolled in this prospective study. Culture-negative osteoarticular specimens were tested by 16S rDNA PCR and by K. kingae-specific real-time PCR when sufficient sample remained. Results: By culture alone, a pathogen was identified in 45% of the 131 specimens tested (Staphylococcus aureus, n = 25; K. kingae, n = 17; others, n = 18). 16S rDNA PCR and K. kingae-specific PCR were both applied to 61 of the culture-negative samples. The combination of culture and 16S rDNA PCR identified a pathogen in 61% of cases (K. kingae DNA, n = 16; DNA of other microorganisms, n = 5). Specific real-time PCR identified a further 6 cases caused by K. kingae and confirmed all 16 universal PCR-positive cases, bringing the overall documentation rate to 66%. K. kingae was the leading cause of OAI in this pediatric series (n = 39, 45%), followed by S. aureus (n = 25, 29%) Conclusion: The K. kingae-specific real-time PCR places K. kingae as the leading cause of OAI in children at our hospital.

Contribution of a broad range polymerase chain reaction to the diagnosis of osteoarticular infections caused by Kingella kingae: description of twenty-four recent pediatric diagnoses.

Background: Microbiologic diagnosis of septic arthritis and osteomyelitis in children is hindered by the less than optimal yield of blood and osteoarticular fluid cultures. Patients and Methods: All patients admitted to a pediatric unit for osteoarticular infections (OAI) between January 2001 and February 2004 were enrolled in this prospective study. Osteoarticular fluid and biopsy samples that were negative by conventional culture were tested by polymerase chain reaction (PCR) with universal 16S ribosomal DNA primers. Results: We enrolled 171 children. Culture was positive in 64 cases (37.4%), yielding Kingella kingae in 9 cases. The 107 culture-negative specimens were tested by 16S ribosomal DNA PCR. Fifteen samples (14%) were positive, all for Kingella DNA sequences. K. kingae was the second cause of OAI in this population (30.4%), after Staphylococcus aureus (38%). Patients with Kingella infection diagnosed by culture (9 cases) did not differ from those diagnosed by PCR (15 cases) in terms of their clinical characteristics (including prior antibiotic therapy). The characteristics of the 24 children with arthritis (n = 17) or osteomyelitis (n = 7) were similar to those reported elsewhere. Fever (>38°C) and symptom onset shortly before hospitalization (median, 4.5 days) were significantly associated with arthritis. Conclusion: Use of molecular diagnostic methods increases the identification of K. kingae in osteoarticular infections.

Latex allergy in children: modalities and prevention.

Allergic or immediate hypersensitivity reactions to latex have been reported in children with increasing frequency in the past. The reported prevalence varies greatly depending upon the population studied and the methods used to detect sensitization. Children’s subpopulations at particular risk include: atopics, individuals with spina bifida, children undergoing surgical procedure during the neonatal period and individuals who required frequent surgical instrumentations. Latex allergy is also an important medical issue, particularly for healthcare personnel. Sensitization mainly occurs by wound or mucosal contact with latex devices during surgery or by inhalation of airborne allergens released from powdered latex gloves. Regarding diagnosis, the medical history, skin prick test and search for specific serum IgE are crucial but cost effective. The development of a guide listing latex‐containing drugs is essential for the primary prevention of allergic reactions. Immunotherapy or specific premedication seems not effective in preventing the risk of anaphylaxis during the perioperative course. The most effective strategy to decrease the incidence of latex sensitization is complete avoidance. This strategy is efficient in patients and also in health care workers and has been applied since 2002 in our pediatric surgical hospital. One of major problem with the latex‐free gloves was that surgeons find them considerably more difficult to work with. But today, manufacturers made considerable effort and free‐latex gloves with an equal tactile sensation than the latex‐gloves are now available. The extra cost of free latex gloves is well counterbalanced as allergen test, long stay hospital for allergic reaction, and worker’s compensation are no longer needed. Since the introduction of this program in our institution, no allergic reaction to latex has been reported in 25000 anesthetized children or with the health care workers.

Comparative study: Ponseti method versus French physiotherapy for initial treatment of idiopathic clubfoot deformity.

Background Nonoperative treatment avoids the complications after extensive surgery for idiopathic clubfeet. The purpose of this study was to compare retrospectively French physiotherapy and Ponseti method used to treat idiopathic clubfoot in 2 institutions. Methods Two hundred nineteen idiopathic clubfeet (146 patients) managed during a 3-year period (2000 to 2003) were included in this study: 116 clubfeet in group FM were treated according to modified French physiotherapy (with percutaneous heel-cord tenotomy in 17%) and 103 clubfeet in group PM were treated according to the Ponseti method. The use of further surgery was considered as failure of the nonoperative management: complete posteromedial release were noted poor, limited posterior release were noted fair, and nonrelease surgery or nonoperated feet were scored with the modified Ghanem score. Results After a mean follow-up of 5.5 years (range, 2.5 to 7.4 y), similar rate of surgery was performed in both groups (21% in group FM and 16% in group PM) but complete posteromedial release was mainly done in group FM (19% of feet), and limited surgery was done in group PM. Results were noted excellent, good, fair, and poor in respectively 55%, 20%, 6%, and 19% of patients in group FM and 79%, 15%, 4%, and 2% of patients in group PM. Results for Dimeglio grade II clubfeet were not different, but results for grade III and grade IV clubfeet were better in PM group. Conclusions Ponseti method enables reduction of extensive surgery compared with French physiotherapy mainly for severe deformities.

Induced membrane technique for reconstruction after bone tumor resection in children: a preliminary study.

AIM Segmental long-bone defect due to tumor resection remains a challenge to treat. The induced membrane technique is a new alternative for biological reconstruction. During the first stage, a cement spacer is inserted after bone resection and stabilisation. The cement spacer is removed during a second stage procedure performed after chemotherapy, and cortico-cancellous bone autograft was placed in the biological induced chamber. The aim of this study was to assess preliminary results in eight children. PATIENTS AND METHODS This prospective study included six girls and two boys, with a mean age of 12.1 years (range 9.5 to 18) and treated for a mean 15 cm defect (range 10 to 22 cms) due to resection of osteosarcoma (n=4), Ewing sarcoma (n=3) and low grade sarcoma. All patients except one, were given pre- and postoperative chemotherapy. Surgery was performed for three patients with a distal femur tumor, two patients with a proximal tibial tumor and three patients who had proximal humerus, shaft of humerus and fibular tumors. Fixation was mainly performed with locking compression plate (n=4) and locked nail (n=2). The mean operating times for first and second step procedures were 4.8 and 4h respectively. The healing process was radiologically assessed. RESULTS After a mean follow-up of 21.6 months (15 to 30), all patients were free of disease and seven had bony union. For the lower limb reconstructions, full weight bearing was possible after a mean of 116 days (range 90 to 150) following the second stage. Mean time to bone union was 4.8 months (1.5 to 10). The early Musculoskeletal Tumor Society (MSTS) score was 25.2/30 (range 20-30). Complications were: non-union (n=1), paradoxical graft resorption (n=1) requiring graft revision. CONCLUSION This two stage procedure reduces the operating time during the first stage and it also reduces early complications. Rapid bone union is objectively obtained despite major bone resection and the patients receiving chemotherapy. SIGNIFICANCE The induced membrane technique could be an excellent alternative for biological reconstruction after tumor resection in children.

Osteoid osteoma transformation into osteoblastoma: fact or fiction?

BACKGROUND Osteoid osteoma and osteoblastoma are rare, benign, bone-forming tumours. The clinical presentation, imaging study findings, and course indicate clearly that these two tumours are distinct entities. CLINICAL REPORTS We report two cases suggesting transformation of osteoid osteoma into osteoblastoma and therefore inviting a discussion of the links between these two tumours. An 11-year-old girl with a small metaphyseal lesion of the proximal tibia was given a diagnosis of osteoid osteoma. Over the next few weeks, worsening pain and marked tumour growth prompted a biopsy, which was consistent with an aggressive osteoblastoma. A review of the case suggested primary osteoblastoma at the earliest stage of development. In a 14-year-old boy, en-bloc excision was performed to remove a 1cm defect located within the femoral shaft cortex and typical for osteoid osteoma. An asymptomatic recurrence measuring 20mm along the long axis was removed 18 months later. Reassessment of the histological slides indicated recurrence of an incompletely excised osteoid osteoma. DISCUSSION The histological similarities between osteoid osteoma and osteoblastoma, together with the lesion size criterion, may result in confusion. Collaboration between the clinician and pathologist is crucial and should take the tempo of evolution into account. CONCLUSION The histopathological differences between these two tumour types deserve to be emphasized. The data reported here challenge the concept that osteoid osteoma can transform into osteoblastoma. These two tumours are distinct entities that should no longer be differentiated based on size, as was long done in the past.

Bone stiffness in children: part II. Objectives criteria for children to assess healing during leg lengthening.

Background: The decision when to remove the frame after limb lengthening through standard distraction osteogenesis remains a challenge. Multiple studies have attempted to find objective criteria to assess bone healing after fracture or bone lengthening. However, there is a paucity of such data for the pediatric population. The purpose of this study was to correlate data obtained after dual-energy x-ray absorptiometry (DXA) measurement and bending stiffness in children to find an end-point value for the safe removal of an external fixation device. Methods: We investigated 16 consecutive children aged between 5.5 and 16.7 years who had 22 lengthenings by callotasis. Twelve femurs and 10 tibiae were lengthened with a monoplane Orthofix external fixator. Fifty simultaneous measurements of bending bone stiffness measured with an Orthometer and DXA scans (bone mineral content [BMC], bone mineral density, volumetric bone mineral density, BMC/1 cm, Area/1 cm, BMC/1 cm, Area) were obtained during healing process. Four femoral fractures were reported after the removal of the external fixation device. Linear regression analysis was used to calculate the squared correlation coefficients for the relation between the DXA scans and the mechanical tests measuring bone stiffness. Results: The bone stiffness measurement of the intact bone was compared with consecutive measurements of the bone stiffness of the regenerate, and it was expressed as a percentage (coefficient). We compared the BMC of the regenerate with the same bone area of the opposite limb. The best correlation was observed for anteroposterior (AP) bone stiffness coefficient and BMC coefficient (R2 = 0.82). The linear equation was BMC coefficient = 0.5 × AP stiffness coefficient + 30. The end point of 75% of BMC of the regenerate corresponds to 75% of the AP stiffness on DXA scanning; this is the time when we should consider safe removal of the fixator. Conclusions: Our method of comparing bone stiffness and DXA measurements gives an objective healing end point for every patient irrespective of his or her size. This method could allow noninvasive measurement of the end point and identified at-risk population of children, reducing regenerate fracture after bone lengthening.

Bone stiffness in children: part I. In vivo assessment of the stiffness of femur and tibia in children.

Although there are many publications concerning the mechanical behavior of adult bone, there are few data about mechanical properties of childrens bone. In vivo bone stiffness measurement with Orthometer device has been validated and extensively used in adults to assess bone healing after fracture or lengthening. We hypothesized that in vivo stiffness measurement with Orthometer was applicable in children and was correlated with age, height, body weight, and corpulence index. The purpose was to establish baseline stiffness values for femur and tibia in growing children. Sixteen bone measurements (7 femurs and 9 tibias) were obtained during application of an external fixator for leg lengthening in 11 children aged between 5.5 and 16.7 years. A 3-point bending test with an Orthometer was carried out on the intact bone (before osteotomy) under general anesthesia. The anteroposterior stiffness measurement was successful in all children of the series, aged from 5.5 to 16.7 years. A wide variation of femoral and tibial bone stiffness values were observed. The use of a unique value as in adults as the end point of bending stiffness during bone healing process is not possible for children. The anteroposterior bone stiffness was found to have linear correlation with childrens height and body weight, but not with age and corpulence indexes. The original data obtained by this study will give a stiffness reference for height and weight and could be useful as reference values for monitoring of healing process after fracture or limb lengthening.

Acl Reconstruction in Children: An Original Technique

Early reconstruction after anterior cruciate ligament (ACL) rupture in children with open physis was found to be a better strategy compared with delayed ACL reconstruction at skeletal maturity. This article focuses on an original technique for ACL reconstruction in children and adolescents. The rationale of the procedure is based on avoiding the danger of a femoral tunnel and fixation systems that may lead to growth arrest. Part of the quadriceps tendon with a trapezoidal patella bone block was harvested after arthroscopic exploration and addressing other intra-articular injuries like meniscal tears. The bone-tendon graft was inserted through a combined intraepiphyseal femoral tunnel drilled from outside-in under fluoroscopic imaging and a long vertical arthroscopically drilled transphyseal tibial tunnel. The bone block was impacted in the femoral tunnel, allowing primary fixation without any associated material. The tibial fixation is obtained with a strictly metaphyseal screw and postfixation with a staple. The advantages of the technique are multiple: anatomic and isometric reconstruction, arthroscopically surgery, strong adaptable long graft with excellent bone to bone press-fit fixation on the femur, and preservation of the femoral physis. Indications, the step-by-step procedure, postoperative care, complications, and results are reported in this paper.

A specific closed percutaneous technique for reduction of Jeffery type II lesion.

Open reduction is commonly recommended in Jeffery type II fractures. Attempts to reduce these fractures percutaneously were reported as unsafe and unreliable. We revisited this technique and used a specific percutaneous reduction that turned out to be successful in two cases. Instead of lifting the radial head as described in leverage maneuver, we use a pushing-back procedure to reduce the fracture. The maneuver aims at suppressing the capitellum interposition between the head fragment and the metaphysis by reproducing the reversed trajectory of trauma. This reduction is made possible because of the posterior periosteal attachment of the radial head. A few weeks after the procedure, the two patients remained painless, recovered a complete range of motion in prono-supination and returned to sports. In these two cases, the procedure used led to a prompt recovery and provided a much better outcome than described with the classic open approach.