The role of 99mTc-DPD bone SPECT/CT in the management of growth disturbance of the long bones in pediatric patients: a retrospective observational study.

BACKGROUNDS: Determining the precise localization of diseased physes is crucial for guiding the treatment of growth disturbances. Conventional radiography, computed tomography (CT), and magnetic resonance imaging only provide information on physeal anatomy. Planar bone scintigraphy and bone single-photon emission computed tomography (SPECT) resolutions are suboptimal for clinically managing growth disturbances. Bone SPECT/CT, which provides high-resolution functional information, can be a useful tool for evaluating growth disturbances. The purposes of this study were to identify the conditions in which bone SPECT/CT outperforms planar scintigraphy or SPECT for evaluating the location and activity of diseased physes and to assess surgical outcomes using bone SPECT/CT findings in pediatric patients experiencing long bone growth disturbances. METHODS: Fifty-nine patients who underwent bone SPECT/CT between January 2018 and January 2021 to evaluate physeal activity using technetium-99 m-labeled 2,3-dicarboxypropane-1,1-diphosphonate (99mTc-DPD) were included. The proportions of patients for whom certain modalities provided sufficient data for selecting treatment plans for growth disturbances were compared based on the site of the diseased physis, growth disturbance cause, and shape of deformity (i.e., SPECT/CT vs. planar scintigraphy and SPECT/CT vs. SPECT). For assessing surgical outcomes, progression of post-surgical deformity was investigated by measuring the angles reflecting the degree of deformity, iliac crest height difference, or ulnar variance on radiographs. RESULTS: Bone SPECT/CT was sufficient for selecting a treatment plan, but planar scintigraphy or SPECT alone was insufficient in every 10 patients with diseased physes inside the femoral head (p = 0.002) and in every six with physes that were severely deformed or whose locations were unclear on conventional radiography (p = 0.03). In the proximal or distal tibia, where the tibial and fibular physes often overlapped on planar scintigraphy due to leg rotation, bone SPECT/CT was sufficient in 33/34 patients (97%), but planar scintigraphy and SPECT were sufficient in 10/34 (29%) (p < 0.001) and 24/34 (71%) patients, respectively (p = 0.004). No progression or deformity recurrence occurred. CONCLUSIONS: Bone SPECT/CT may be indicated in proximal femoral growth disturbance, when the physis is unclear on conventional radiography or severely deformed, the leg exhibits rotational deformity, or the patient is noncompliant.

Clinical and radiological outcomes of surgically treated osteochondral lesions of the talus in children and adolescents.

Background: Osteochondral lesions of the talus are uncommon in children and adolescents. Surgical procedures differ from those used for adults to avoid iatrogenic physeal injuries. This study aimed to evaluate the clinical and radiological outcomes of surgical treatment in pediatric patients with osteochondral lesions, specifically investigating the patient age and the status of distal tibial physis as factors associated with surgical success. Methods: We retrospectively reviewed 28 patients who had symptomatic osteochondral lesions of the talus that were treated surgically between 2003 and 2016. If the lesion was stable and articular cartilage was intact, retrograde drilling was performed under fluoroscopic guidance. Lesions with detached overlying cartilages were treated by debridement of the cartilage combined with microfracture and drilling. Radiographic outcomes, American Orthopaedic Foot & Ankle Society ankle-hindfoot score, and skeletal maturity were evaluated. Results: Radiological improvement was observed in 24 (24/28, 86%) patients and complete and incomplete healing in 8 and 16 patients, respectively. Changes in pain grades, American Orthopaedic Foot & Ankle Society scores, and radiological healing after surgery were significant (pain grade, p < 0.001; American Orthopaedic Foot & Ankle Society, p = 0.018; radiological healing, p < 0.001). In addition, patients in the younger age group (≤13 years) showed greater improvements in pain grades than older patients (p = 0.02). Improvement in pain grade after surgery was better in the skeletally immature group than in the skeletally mature group (p = 0.048). Conclusion: Clinical and radiological improvements were observed after surgical treatment. The younger age group and open physis group showed more pain improvement. Level of evidence: Therapeutic level IV.

Effect of Leg Length Discrepancy on Lateral Center-edge Angle Measurement.

BACKGROUND: In patients with leg length discrepancy (LLD) and consequent pelvic obliquity, either the longitudinal axis of the pelvis or a line perpendicular to the ground may be used as the longitudinal reference line for measuring the lateral center-edge angle (LCEA). We aimed to (1) systematically inspect which longitudinal reference line has been used for measuring the LCEA in previous studies; (2) evaluate the frequency of change in the radiographical classification of acetabular overcoverage or undercoverage per the longitudinal reference line; and (3) validate the trigonometric method, predicting the change in the LCEA according to the LLD. METHODS: Studies investigating the LCEA published between January 1976 and July 2019 in the MEDLINE database were categorized according to the longitudinal reference line used. Further, in a retrospective analysis of 238 patients surgically treated for LLD, the LCEA was first measured on standing pelvic radiographs using the longitudinal axis of the pelvis (pLCEA) and measured again using a line perpendicular to the ground (gLCEA). Femoral head coverage was categorized as undercoverage, normal, or overcoverage based on the pLCEA and gLCEA. The theoretically calculated difference between the pLCEA and gLCEA (dLCEA) as determined using a trigonometric method was compared with the dLCEA measured on radiographs. RESULTS: Of 229 previous studies, 188 did not specify the longitudinal reference line. The number of patients who were diagnosed with acetabular overcoverage using the pLCEA and gLCEA was one and fourteen, respectively (P<0.001). The number of patients who were diagnosed with acetabular undercoverage using the pLCEA and gLCEA was one and zero, respectively (P=1.000). There was no difference (P=0.433) between the theoretically calculated (9±5 degrees) and measured (9±5 degrees) dLCEAs. CONCLUSIONS: The definition of the longitudinal reference line should be clarified when measuring the LCEA. The trigonometric method can accurately predict the change in the LCEA according to LLD in concentric hips without proximal femoral and pelvic deformities. LEVEL OF EVIDENCE: Level IV-diagnostic study.

Patterns of femoral neck fracture and its treatment methods in patients with osteogenesis imperfecta.

Femoral neck fracture (FNF) is not common in osteogenesis imperfecta patients but may result in serious complications if not properly treated in due time. We present three types of FNF in osteogenesis imperfecta and their characteristics, treatment methods and outcomes. Cases of FNF followed for more than 2 years were selected from the osteogenesis imperfecta database. Medical records and radiographs were reviewed to obtain demographic information and to determine ambulatory status, mode of injury, location of the fracture line, presence of preexisting implants, treatment methods and complications. Outcomes were evaluated according to the radiographic results and ambulatory function. The study investigated 15 FNFs in 10 patients including 1 Sillence type I, 1 type III and 8 type IV. They were either community or household ambulators. The mean age at fracture was 11.7 years. The fractures were followed for an average of 6.3 years. Six fractures were attributed to accidental injuries and nine without noticeable trauma. The fracture pattern was categorized into undisplaced (n = 3), angulated-stable (n = 7) or displaced-unstable (n = 5) types. Five fractures were fixed in-situ using screws or Kirschner wires. Other five fractures were treated by closed reduction and screw fixation and the remaining five fractures were managed by femoral valgus osteotomy. Bony union was achieved, and prefracture ambulatory status was restored in all cases. A high index of suspicion is required in the diagnosis of undisplaced or angulated-stable fractures. Treatment is usually challenging, but a judicious approach considering the fracture pattern and patient characteristics result in successful outcomes. The angulated-stable pattern of fracture is unique in osteogenesis imperfecta patients and requires special attention.

Intra-articular acetabular osteochondroma in patients with multiple hereditary exostoses.

We report three additional cases of intra-articular acetabular osteochondroma in multiple hereditary exostoses patients in order to raise the awareness of this rare location, to prompt early diagnosis, and to present various treatment options according to the patient's condition. A 2.5-year-old boy presenting with an out-toeing gait had a large acetabular osteochondroma causing lateral displacement of the femoral head and acetabular dysplasia. Mass excision through hip subluxation via anterior approach and concomitant Dega osteotomy resulted in a congruent, well-developed, and well-covered hip joint at 11-year follow-up. A 10-year-old boy showing a pedunculated osteochondroma arising from the triradiate cartilage was successfully treated by arthroscopic excision. Normal development of the hip joint was observed at skeletal maturity. A 6-year-old boy presented with a painless limp. Acetabular osteochondroma could be confirmed by computed tomography scan, which was excised through hip subluxation by anterior approach. Persistent coxa valga and femoral head uncovering were addressed by femoral varization osteotomy at 9 years of age. A high index of suspicion is required to detect a lesion at this rare location. Various procedures may be considered according to the pathoanatomy. Acetabular dysplasia, coxa valga, and femoroacetabular impingement by femur neck mass, if associated, should be addressed in due time.

Prospective study of epigenetic alterations responsible for isolated hemihyperplasia/hemihypoplasia and their association with leg length discrepancy.

BACKGROUND: Hemihyperplasia and hemihypoplasia result in leg length discrepancy (LLD) by causing skeletal asymmetry. Beckwith-Wiedemann syndrome (BWS) and Silver-Russell syndrome (SRS) are opposite growth-affecting disorders caused by opposite epigenetic alterations at the same chromosomal locus, 11p15, to induce hemihyperplasia and hemihypoplasia, respectively. Because of their somatic mosaicism, BWS and SRS show a wide spectrum of clinical phenotypes. We evaluated the underlying epigenetic alterations and potential epigenotype-phenotype correlations, focusing on LLD, in a group of individuals with isolated hemihyperplasia/hemihypoplasia. RESULTS: We prospectively collected paired blood-tissue samples from 30 patients with isolated hemihyperplasia/hemihypoplasia who underwent surgery for LLD. Methylation-specific multiplex-ligation-dependent probe amplification assay (MS-MLPA) and bisulfite pyrosequencing for differentially methylated regions 1 and 2 (DMR1 and DMR2) on chromosome 11p15 were performed using the patient samples. Samples from patients showing no abnormalities in MS-MLPA or bisulfite pyrosequencing were analyzed by single nucleotide polymorphism (SNP) microarray and CDKN1C Sanger sequencing. We introduced a metric named as the methylation difference, defined as the difference in DNA methylation levels between DMR1 and DMR2. The correlation between the methylation difference and the predicted LLD at skeletal maturity, calculated using a multiplier method, was evaluated. Predicted LLD was standardized for stature. Ten patients (33%) showed epigenetic alterations in MS-MLPA and bisulfite pyrosequencing. Of these, six and four patients had epigenetic alterations related to BWS and SRS, respectively. The clinical diagnosis of hemihyperplasia/hemihypoplasia was not compatible with the epigenetic alterations in four of these ten patients. No patients showed abnormalities in SNP array or their CDKN1C sequences. The standardized predicted LLD was moderately correlated with the methylation difference using fat tissue (r = 0.53; p = 0.002) and skin tissue (r = 0.50; p = 0.005) in all patients. CONCLUSIONS: Isolated hemihyperplasia and hemihypoplasia can occur as a spectrum of BWS and SRS. Although the accurate differentiation between isolated hemihyperplasia and isolated hemihypoplasia is important in tumor surveillance planning, it is often difficult to clinically differentiate these two diseases without epigenetic tests. Epigenetic tests may play a role in the prediction of LLD, which would aid in treatment planning.

Acute correction of proximal tibial coronal plane deformity in small children using a small monolateral external fixator with or without cross-pinning.

PURPOSE: Surgical correction of proximal tibia deformity in small children can be challenging. We present the surgical technique and outcome of proximal tibia osteotomy fixed with small monolateral external fixator in this patient group. METHODS: A total of 17 cases in eight patients younger than nine years of age were study subjects. A proximal tibia osteotomy was fixed with a small monolateral external fixator with or without cross-pinning. Outcome was evaluated by changes of radiographic parameters such as medial proximal tibia angle (MPTA), metaphyseal diaphyseal angle (MDA) and clinical findings of complications, time interval until weight bearing and fixator removal time. RESULTS: MPTA improved from a preoperative mean of 73° (sd 4°; 66° to 78°) to an immediate postoperative mean of 90° (sd 3°; 85° to 96°) in varus tibiae, and from 104° (sd 1°; 103° to 105°) to 89° (sd 1°; 88° to 89°) in valgus tibiae. In all, 15 of the 17 cases (88.3 %) achieved postoperative MPTA within the normal range (85° to 90°). MDA improved from a preoperative mean of 19° (sd 5°; 11° to 24°) to an immediate postoperative mean of 0° (sd 4°; -6° to 7°) in varus tibiae, and from -25° (sd 2°; -22° to -24°) to 2° (SD 1°; 1° to 3°) in valgus tibiae. Full weight bearing was possible at mean 1.7 months (0.5 to 3.0). Mean follow-up period was 6.5 years (sd 5.4; 1.0 to 16.0). No complications developed during the follow-up. CONCLUSION: Proximal tibia osteotomy fixed with small monolateral external fixator provides accurate, safe and efficient correction in the management of coronal plane angular deformity in small children. LEVEL OF EVIDENCE: Level IV.

MRI risk factors for development of avascular necrosis after closed reduction of developmental dysplasia of the hip: Predictive value of contrast-enhanced MRI.

PURPOSE: The purpose of this study was to identify imaging risk factors on contrast-enhanced hip MRI after closed reduction of developmental dysplasia of the hip (DDH) that could predict future development of avascular necrosis (AVN) of the femoral head. MATERIALS AND METHODS: Fifty-eight infants (F: M = 53: 5, aged 3-18 months) who underwent immediate postoperative contrast-enhanced hip MRI after closed reduction of DDH were included in this study. Quality of reduction (concentric vs eccentric reduction with or without obstacles), abduction angle of the hip, presence of ossific nucleus, and pattern of contrast enhancement of the femoral head were retrospectively evaluated on MRI. Interobserver agreement of contrast enhancement pattern on MRI were evaluated by two radiologists. Development of AVN was determined through radiographic findings at 1 year after reduction. RESULTS: AVN of the femoral head developed in 13 (22%) of 58 patients. Excessive abduction of the hip joint (OR 4.65, [95% CI 1.20, 18.06] and global decreased enhancement of the femoral head (OR 71.66, [95% CI 10.54, 487.31]) exhibited statistically significant differences between the AVN and non-AVN groups (P < 0.05). Eccentric reduction (P = 0.320) did not show statistically significant difference between two groups and invisible ossific nucleus (P = 0.05) showed borderline significance. Multi-variable logistic regression indicated that global decreased enhancement of the femoral head was a significant risk factor of AVN (OR 27.92, 95% CI [4.17, 350.18]) (P = 0.0031). Interobserver agreement of contrast enhancement pattern analysis and diagnosis of AVN were good (0.66, 95% CI [0.52, 0.80]). CONCLUSION: Contrast-enhanced hip MRI provides accurate anatomical assessment of the hip after closed reduction of DDH. Global decreased enhancement of the femoral head could be used as a good predictor for future development of AVN after closed reduction of DDH.

Pseudo-Protrusio Acetabular Deformity in Osteogenesis Imperfecta Patients.

BACKGROUND: Osteogenesis imperfecta (OI) can develop a protrusio acetabuli deformity. However, the authors observed a pseudo-protrusio-type acetabular deformity (PPAD) on 3-dimensional computed tomography (3D-CT). Hence, we systematically reviewed 3D-CT and pelvis radiographs of OI patients and report the incidence and patterns of acetabular deformity in OI patients and the associated radiographic signs. METHODS: The study included 590 hips of 295 OI patients, who were older than 5 years, and did not have a pelvic fracture. The incidence of a deformed acetabulum (center-edge angle >40 degrees) and its correlation with disease severity were investigated. In 40 hips for which 3D-CT was available, 3-dimensional morphology of the acetabular deformity was analyzed to delineate PPAD. On plain radiographs, PPAD-related signs were determined, focusing on the contour of ilioischial line, iliopectineal line, acetabular line, and their relationship. These radiographic signs were also evaluated in the remaining hips with deformed acetabula that did not have 3D-CT. RESULTS: One hundred twenty-three hips of 590 hips (21%) showed deformed acetabula. The incidence of deformed acetabula was significantly associated with disease severity (P<0.001). Three-dimensional analysis showed that 10 hips had protrusio acetabuli, whereas 17 had PPAD, which showed that the hemipelvis was crumpled, the acetabular roof was rotated upwardly and medially, and the hip center migrated superiorly, uncovering the anterior femoral head. Among the PPAD-related signs, superomedial bulging of the iliopectineal line was the most predictive radiographic sign (73% sensitivity and 100% specificity). This sign was also observed in almost one third of deformed acetabula of those investigated only with plain radiographs. CONCLUSIONS: This study showed that acetabular deformity is common in OI patients and is associated with disease severity. A substantial number of hips showed PPAD, which may not cause femoroacetabular impingement but result in anterior uncovering of the hip joint. Superomedial bulging of the iliopectineal line suggests this pattern of acetabular deformity. LEVEL OF EVIDENCE: Lever IV-prognostic studies.

Management of Osteogenesis Imperfecta: A Multidisciplinary Comprehensive Approach.

Osteogenesis imperfecta (OI) is characterized by recurring fractures and limb and spine deformities. With the advent of medical therapeutics and the discovery of causative genes, as well as the introduction of a newly devised intramedullary rod, the general condition and ambulatory function of patients diagnosed with OI have been improved over the past decades. This review covers recent developments in research and management of OI.

Effective and Rapid Microbial Identification in Pediatric Osteoarticular Infections Using Blood Culture Bottles.

BACKGROUND: The detection and identification of pathogenic microorganisms are essential for the treatment of osteoarticular infection. However, obtaining a sufficient amount of specimen from pediatric patients is often difficult. Herein, we aimed to demonstrate the effectiveness of the blood culture bottle (BCB) system in pediatric osteoarticular infections. We hypothesized that our BCB culture method is superior to the conventional swab and tissue culture methods in terms of required specimen size, incubation time, and microbial identification rate. METHODS: We analyzed the prospectively collected data of pediatric patients who underwent surgical treatment for osteoarticular infections between August 2016 and October 2019. Four needles were dipped in the infected fluid or tissue during the surgical procedure as soon as the infected area was exposed and were used to inoculate 2 aerobic pediatric BCBs and 2 anaerobic general BCBs. We also collected 2 conventional swab samples and 2 tissue samples from the identical area. The microbial identification rate and the time required for identification were compared between BCB, swab, and tissue cultures. RESULTS: Forty patients constituted the study group; 13 patients had osteomyelitis, 17 patients had septic arthritis, and 10 patients had both. Of these 40 patients, the microbial identification rate was higher with BCB cultures (27 [68%]) than with swab cultures (18 [45%]; p = 0.004) or tissue cultures (15 [38%]; p < 0.001). Nine samples (9 patients [23%]) were only positive in the BCB culture. Positive microbial growth was not detected with conventional culture methods when microorganisms did not grow on the BCB culture. Compared with swab culture (4.3 ± 1.1 days; p < 0.001) or tissue culture (4.4 ± 1.1 days; p < 0.001), the BCB culture reduced the time required for microbial identification (3.5 ± 0.9 days). CONCLUSIONS: In pediatric osteoarticular infections, the BCB culture system improved the microbial identification rate, reduced the time to identification, and permitted a smaller-volume specimen, compared with traditional culture systems. LEVEL OF EVIDENCE: Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Detailed analysis of phenotypes and genotypes in megalencephaly-capillary malformation-polymicrogyria syndrome caused by somatic mosaicism of PIK3CA mutations.

BACKGROUND: Megalencephaly-capillary malformation-polymicrogyria syndrome (MCAP) belongs to a group of conditions called the PIK3CA-related overgrowth spectrum (PROS). The varying phenotypes and low frequencies of each somatic mosaic variant make confirmative diagnosis difficult. We present 12 patients who were diagnosed clinically and genetically with MCAP. Genomic DNA was extracted mainly from the skin of affected lesions, also from peripheral blood leukocytes and buccal epithelial cells, and target panel sequencing using high-depth next-generation sequencing technology was performed. RESULTS: Macrocephaly was present in 11/12 patients (92%). All patients had normal body asymmetry. Cutaneous vascular malformation was found in 10/12 patients (83%). Megalencephaly or hemimegalencephaly was noted in all 11 patients who underwent brain magnetic resonance imaging. Arnold-Chiari type I malformation was also seen in 10 patients. Every patient was identified as having pathogenic or likely pathogenic variants of the PIK3CA gene. The variant allele frequency (VAF) ranged from 6.3 to 35.3%, however, there was no direct correlation between VAF and the severity of associated anomalies. c.2740G > A (p.Gly914Arg) was most commonly found, in four patients (33%). No malignancies developed during follow-up periods. CONCLUSIONS: This is the first and largest cohort of molecularly diagnosed patients with MCAP in Korea. Targeted therapy with a PI3K-specific inhibitor, alpelisib, has shown successful outcomes in patients with PROS in a pilot clinical study, so early diagnosis for genetic counseling and timely introduction of emerging treatments might be achieved in the future through optimal genetic testing.

Which Acetabular Landmarks are the Most Useful for Measuring the Acetabular Index and Center-edge Angle in Developmental Dysplasia of the Hip? A Comparison of Two Methods.

BACKGROUND: The acetabular index and center-edge angle are widely used radiographic parameters. However, the exact landmarks for measuring these parameters are not clearly defined. Although their measurement is straightforward when the lateral osseous margin of the acetabular roof coincides with the lateral end of the acetabular sourcil, where these two landmarks disagree, recommendations have differed about which landmark should be used. Using a radiographic parameter with high reliability for predicting residual hip dysplasia helps avoid unnecessary treatment. QUESTIONS/PURPOSES: We aimed to (1) compare two landmarks (the lateral osseous margin of the acetabular roof and the lateral end of the acetabular sourcil) for measuring the acetabular index and center-edge angle with respect to intraobserver and interobserver reliability and the predictability of residual hip dysplasia in patients with developmental dysplasia of the hip (DDH) and (2) evaluate longitudinal change in the acetabular edge's shape after closed reduction with the patient under general anesthesia. METHODS: Between February 1985 and July 2006, we performed closed reduction with the patient under general anesthesia as well as cast immobilization in 116 patients with DDH. To be included in this study, a patient had to have dislocated-type DDH. We excluded patients with a hip dislocation associated with neuromuscular disease, arthrogryposis, or congenital anomalies of other organs or systems (n = 9); hips that underwent osteotomy within 1 year since closed reduction (n = 8); hips that underwent open reduction because of re-dislocation after closed reduction (n = 4); and hips with Type III or IV osteonecrosis according to Bucholz-Ogden's classification (n = 4). Ninety-one patients were eligible. We excluded 19% (17 of 91) of the patients, who were lost to follow-up before they were 8 years old, leaving 81% (74 of 91 patients) with full preoperative and most-recent data. Ninety-seven percent (72 patients) were girls and 3% (two patients) were boys. The mean ± standard deviation age was 14.0 months ± 6.4 months (range 3-40 months) at the time of closed reduction and 12.1 years ± 2.3 years (range 8.0-16.0 years) at the time of the latest follow-up examination, the duration of which averaged 11 years ± 2.2 years (range 6.5-15.4 years). To investigate whether longitudinal change in the acetabular edge's shape differed among hips with DDH, contralateral hips, and control hips, we identified control participants after searching our hospital's database for patients with a diagnosis of congenital idiopathic hemihypertrophy from October 2000 to November 2006 who had AP hip radiographs taken at 3 years old and then at older than 8 years. From 29 patients who met these criteria, we randomly excluded two male patients to match for sex because girls were predominant in the DDH group. We excluded another female patient from the control group because of a hip radiograph that revealed unacceptable rotation. Eventually, 26 patients were assigned to the control group. Control patients consisted of 24 girls (92%) and two boys (8%). The demographic characteristics of control patients was not different from those of 67 patients with unilateral DDH, except for laterality (left-side involvement: 64% [43 of 67] in the DDH group versus 38% [10 of 26] in the control group; odds ratio 1.7 [95% confidence interval, 1.0-2.8]; p = 0.035). The acetabular index and center-edge angle at 3 years old were measured using the lateral osseous margin of the acetabular roof (AIB and CEAB) and the lateral end of the acetabular sourcil (AIS and CEAS). The treatment outcome was classified as satisfactory (Severin Grade I or II) or unsatisfactory (Grade III or IV). The intraclass correlation coefficient (ICC) was used to compare the intraobserver and interobserver reliability of each method. We compared the predictability of residual hip dysplasia of each method at 3 years old as a proxy using the area under the receiver operating characteristic (AUC) curve. To evaluate longitudinal change in the acetabular edge's shape, we compared the proportion of hips showing coincidence of the two landmarks between 3 years old and the latest follow-up examination. To investigate whether the longitudinal change in the acetabular edge's shape differs among hips with DDH, contralateral hips, and control hips, we compared the proportion of coincidence among the three groups at both timepoints. RESULTS: Intraobserver and interobserver reliabilities were higher for the CEAB (ICC 0.96; 95% CI, 0.94-0.98 and ICC 0.88; 95% CI, 0.81-0.92, respectively) than for the CEAS (ICC 0.81; 95% CI, 0.70-0.88 and ICC 0.69; 95% CI, 0.55-0.79, respectively). The AIB (AUC 0.88; 95% CI, 0.80-0.96) and CEAB (AUC 0.841; 95% CI, 0.748-0.933) predicted residual hip dysplasia better than the AIS (AUC 0.776; 95% CI, 0.67-0.88) and CEAS (AUC 0.72; 95% CI, 0.59-0.84) (p = 0.03 and p = 0.01, respectively). The proportion of hips showing coincidence of the two landmarks increased from 3 years old to the latest follow-up examination in hips with DDH (37% [25 of 67] to 81% [54 of 67]; OR = 8.8 [95% CI, 3.1-33.9]; p < 0.001), contralateral hips (42% [28 of 67] to 85% [57 of 67]; OR = 16.5 [95% CI, 4.2-141.9]; p < 0.001), and control hips (38% [10 of 26] to 88% [23 of 26]; OR = 14 [95% CI, 2.1-592.0]; p = 0.001). The proportion of coincidence in hips with DDH was not different from that in the contralateral hips and control hips at both timepoints. CONCLUSIONS: Measuring the acetabular index and center-edge angle at 3 years old using the lateral osseous margin of the acetabular roof has higher reliability for predicting residual hip dysplasia than that using the lateral end of the acetabular sourcil in patients with DDH treated with closed reduction. Measuring the acetabular index and center-edge angle at an early age using the lateral end of the sourcil may lead to overdiagnosis of residual hip dysplasia and unnecessary treatment. LEVEL OF EVIDENCE: Level III, diagnostic study.

Inter-segmental foot kinematics during gait in elderly females according to the severity of hallux valgus.

The objective of this study was to find the effect of hallux valgus (HV) deformity on the inter-segmental motion of the foot using an MFM with a 15-marker set (DuPont Foot Model, DuFM) in comparison with age and sex controlled healthy adults. Fifty-eight female symptomatic HV patients and 50 female asymptomatic older female volunteers were included in this study. According to the radiographic hallux valgus angle (HVA), the study population was divided into severe HV (SHV, HVA ≥ 40°, n = 25), moderate HV (MHV, 20° ≤ HVA < 40°, n = 47), and control (CON, n = 36). MHV group was divided into symptomatic MHV group (S-MHV, n = 33) and asymptomatic MHV group (A-MHV, n = 14) according to the symptoms associated with HV. For temporal parameters, gait speed and stride length were diminished according to the severity of HV deformity. Sagittal range of motion of hallux and hindfoot decreased significantly in SHV group. Loss of push-off during the preswing phase was observed and forefoot adduction motion during terminal stance was decreased in SHV group. In a subgroup analysis of MHV, asymptomatic HV minimally affects gait and inter-segmental motion during gait. HV deformity affects gait parameters and inter-segmental motion of the foot during gait in proportion to the severity of the deformity. However, the effect of MHV itself on foot kinematics might be limited while pain or arthritic change of the joint might cause changes in gait in patients with symptomatic HV.

Functional Outcomes of Hip Arthroscopy for Pediatric and Adolescent Hip Disorders.

BACKGROUND: There is a paucity of literature on the use of hip arthroscopy for pathologic conditions in skeletally immature patients. Thus, the indications and safety of the procedure are still unclear. The purpose of this study was to investigate the safety and functional outcomes of hip arthroscopy for pediatric and adolescent hip disorders. We further attempted to characterize arthroscopic findings in each disease. METHODS: We retrospectively reviewed 32 children and adolescents with hip disorders who underwent 34 hip arthroscopic procedures at a tertiary care children's hospital from January 2010 to December 2016. We evaluated functional limitations and improvement after operation by using the modified Harris hip score (HHS), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), subjective pain assessment with a visual analog scale (VAS), and range of hip motion as well as the complications of hip arthroscopy. Arthroscopic findings in each disease were recorded. RESULTS: Hip arthroscopy was performed for Legg-Calvé-Perthes disease (n = 6), developmental dysplasia of the hip (n = 6), slipped capital femoral epiphysis (n = 5), idiopathic femoroacetabular impingement (n = 6), sequelae of septic arthritis of the hip (n = 3), hereditary multiple exostosis (n = 2), synovial giant cell tumor (n = 3), idiopathic chondrolysis (n = 2), and posttraumatic osteonecrosis of the femoral head (n = 1). Overall, there was a significant improvement in the modified HHS, WOMAC, VAS, and range of hip motion. Symptom improvement was not observed for more than 18 months in four patients who had dysplastic acetabulum with a labral tear (n = 2) or a recurrent femoral head bump (n = 2). There were no complications except transient perineal numbness in five patients. CONCLUSIONS: Our short-term follow-up evaluation shows that hip arthroscopy for pediatric and adolescent hip disorder is a less invasive and safe procedure. It appears to be effective in improving functional impairment caused by femoroacetabular impingement between the deformed femoral head and acetabulum or intra-articular focal problems in pediatric and adolescent hip disorders.

Overgrowth of the lower limb after treatment of developmental dysplasia of the hip: incidence and risk factors in 101 children with a mean follow-up of 15 years.

Background and purpose - There are few studies on overgrowth of the affected limb after treatment of developmental dysplasia of the hip (DDH). We investigated the incidence of overgrowth and its risk factors in DDH patients.Patients and methods - 101 patients were included in this study. Overgrowth was defined by 2 criteria: when the height of the femoral head of the affected side was higher than that of the contralateral side by more than 10 mm, or by more than 15 mm. The potential risk factors of distinct overgrowth were retrospectively examined using multivariable analysis.Results - When overgrowth was defined as femoral head height difference (FHHD) > 10 mm, its incidence was 44%, and only femoral osteotomy was identified as a significant risk factor with a relative risk (RR) of 1.6 (95% confidence interval [CI] 1.0-2.5). When overgrowth was defined as FHHD > 15 mm, its incidence was 23%, and femoral osteotomy was identified as the only significant risk factor with an RR of 2.3 (CI 1.2-4.5). Overgrowth developed more frequently in patients who underwent femoral osteotomy at the age of 2 to 4 years (87%) than in the others (46%) (p = 0.04).Interpretation - Overgrowth of the affected limb is common in DDH patients. Patients who underwent femoral osteotomy, especially at the age of 2 to 4 years, may require careful follow-up because of the substantial risk for overgrowth.

Diagnosis and Management of Hip Dislocation in Patients with Kabuki Syndrome.

BACKGROUND: Kabuki syndrome is a rare genetic disorder characterized by distinct dysmorphic facial features, growth deficiency, intellectual disabilities, unusual dermatoglyphic patterns, and skeletal abnormalities. The incidence of hip dislocation in Kabuki syndrome ranges from 18% to 62%. We reviewed the outcomes of management of hip dislocations in patients with Kabuki syndrome with special attention to the diagnostic processes for hip dislocation and Kabuki syndrome. METHODS: Among 30 patients with mutation-confirmed Kabuki syndrome, we selected six patients who had hip dislocations and reviewed their medical records and plain radiographs. The modes of presentation and diagnostic processes for both hip dislocations and Kabuki syndrome were investigated. The management and treatment outcomes of hip dislocations in patients with Kabuki syndrome were evaluated. RESULTS: The average age of patients at the time of diagnosis of hip dislocation was 7.7 months (range, 1 week to 22 months). None of the patients were diagnosed as having Kabuki syndrome at that time. Two patients were treated with a Pavlik harness; one, with closed reduction; two, with open reduction and later pelvic and/or femoral osteotomies; and one, with open reduction combined with pelvic osteotomy. The patients were followed up for 5.8 years on average (range, 2.0 to 10.5 years). The radiologic outcome was graded as Severin IA or IB for three patients who were older than 6 years at the latest follow-up (mean age, 9.9 years; range, 7.8 to 12.4 years). In the remaining three patients younger than 6 years (mean age, 3.8 years; range, 2.7 to 5.3 years), the lateral center edge angle was more than 15°. The clinical diagnosis of Kabuki syndrome was made during follow-up after hip dislocation treatment and confirmed by mutational analysis at a mean age of 4.7 years. The mean interval between the diagnosis of hip dislocation and Kabuki syndrome was 4.0 years. CONCLUSIONS: The management of hip dislocation by conservative or surgical method showed successful results. Awareness of Kabuki syndrome could lead to an early diagnosis of this rare disease in patients with hip dislocation and allow for early detection of other underlying conditions and multidisciplinary management.

Physeal and Subphyseal Distraction Osteogenesis in Atrophic-type Congenital Pseudarthrosis of the Tibia: Efficacy and Safety.

PURPOSE: To examine the efficacy, safety, and clinical outcomes of distraction osteogenesis through the physis (PDO) or through subphyseal osteotomy (SPDO) in patients with atrophic-type congenital pseudarthrosis of tibia with proximal tibial dysplasia. METHODS: To validate the efficacy and safety of PDO and SPDO, radiographic and clinical parameters were compared between 5 patients who underwent proximal tibial metaphyseal or metadiaphyseal lengthening as a control (group 1) and 7 patients who underwent PDO or SPDO (group 2). Postoperative complication was also compared between the groups. RESULTS: A significant difference in terms of healing index (group 1, 83.3±24.7 d/cm; group 2, 35.0±11.1 d/cm; P=0.001) and percentage increase (11.0%±3.7% vs. 23.1%±10.5%, P=0.034) was observed between the 2 groups. According to the Paley classification, group 1 included 1 "problems" case and 3 "obstacles" cases, whereas group 2 included 2 "problems" cases and 1 "obstacles" case. According to the Lascombes classification, group 1 included 2 grade IIIb cases and 3 grade IV cases, whereas group 2 included 6 grade I cases and 1 grade IIa case. Severe complications were significantly higher in group 1 compared with the group 2 (P=0.007). CONCLUSIONS: This study demonstrated that PDO or SPDO can be effectively and safely performed for tibial lengthening in atrophic-type congenital pseudarthrosis of tibia patients with proximal tibial dysplasia. LEVEL OF EVIDENCE: Level III.

In Vivo Response of Growth Plate to Biodegradable Mg-Ca-Zn Alloys Depending on the Surface Modification.

Because Mg-Ca-Zn alloys are biodegradable and obviate secondary implant removal, they are especially beneficial for pediatric patients. We examined the degradation performance of Mg-Ca-Zn alloys depending on the surface modification and investigated the in vivo effects on the growth plate in a skeletally immature rabbit model. Either plasma electrolyte oxidation (PEO)-coated (n = 18) or non-coated (n = 18) Mg-Ca-Zn alloy was inserted at the distal femoral physis. We measured the degradation performance and femoral segment lengths using micro-CT. In addition, we analyzed the histomorphometric and histopathologic characteristics of the growth plate. Although there were no acute, chronic inflammatory reactions in either group, they differed significantly in the tissue reactions to their degradation performance and physeal responses. Compared to non-coated alloys, PEO-coated alloys degraded significantly slowly with diminished hydrogen gas formation. Depending on the degradation rate, large bone bridge formation and premature physeal arrest occurred primarily in the non-coated group, whereas only a small-sized bone bridge formed in the PEO-coated group. This difference ultimately led to significant shortening of the femoral segment in the non-coated group. This study suggests that optimal degradation could be achieved with PEO-coated Mg-Ca-Zn alloys, making them promising and safe biodegradable materials with no growth plate damage.

Mycobacterium bovis Osteitis Following Immunization with Bacille Calmette-Guérin (BCG) in Korea.

BACKGROUND: Mycobacterium bovis Bacille Calmette-Guérin (BCG) osteitis, a rare complication of BCG vaccination, has not been well investigated in Korea. This study aimed to evaluate the clinical characteristics of BCG osteitis during the recent 10 years in Korea. METHODS: Children diagnosed with BCG osteitis at the Seoul National University Children's Hospital from January 2007 to March 2018 were included. M. bovis BCG was confirmed by multiplex polymerase chain reaction (PCR) in the affected bone. BCG immunization status and clinical information were reviewed retrospectively. RESULTS: Twenty-one patients were diagnosed with BCG osteitis and their median symptom onset from BCG vaccination was 13.8 months (range, 6.0-32.5). Sixteen children (76.2%) received Tokyo-172 vaccine by percutaneous multiple puncture method, while four (19.0%) and one (4.8%) received intradermal Tokyo-172 and Danish strain, respectively. Common presenting symptoms were swelling (76.2%), limited movement of the affected site (63.2%), and pain (61.9%) while fever was only accompanied in 19.0%. Femur (33.3%) and the tarsal bones (23.8%) were the most frequently involved sites; and demarcated osteolytic lesions (63.1%) and cortical breakages (42.1%) were observed on plain radiographs. Surgical drainage was performed in 90.5%, and 33.3% of them required repeated surgical interventions due to persistent symptoms. Antituberculosis medications were administered for a median duration of 12 months (range, 12-31). Most patients recovered without evident sequelae. CONCLUSION: Highly suspecting BCG osteitis based on clinical manifestations is important for prompt management. A comprehensive national surveillance system is needed to understand the exact incidence of serious adverse reactions following BCG vaccination and establish safe vaccination policy in Korea.