Comparison of the inner side and two-sided approaches for iliac crest bone graft harvesting for pediatric pelvic osteotomy.

BACKGROUND: The iliac crest is one of the most used bone graft sources. In this study, we aimed to identify the effects of inner side and two-sided approaches for iliac crest bone harvesting on post-surgery ilium growth in children. MATERIALS AND METHODS: We retrospectively analyzed 47 patients who underwent pelvic osteotomy and iliac crest bone graft (ICBG) procedures from January 2015 to September 2018. The patients were divided into an inner table ilium exposure group (group A) and the inner-outer table ilium exposure group (group B) and were followed up with radiography in postoperative months 1, 3, 6, and 12, and the growth areas were measured using PACS software. Complications such as damage to the arteries or nerves, ureteral injury, gastrointestinal hernia, ileus, abnormal cosmetic appearance, sensory disturbances, and functional limitations were recorded based on clinical records. RESULTS: There were 22 patients aged 5.3±1.5 years in group A and 25 patients aged 5.9±1.8 years in group B. There were no significant differences in demographics between the two groups, or in growth in the first month. However, bone graft growth at months 3, 6, and 12 was significantly better in group A than in group B. There was no significant difference in complications between the two groups. CONCLUSION: Exposure of only the inner table of the ilium resulted in faster recovery of the bone defect than two-sided exposure in pelvic osteotomy. Therefore, we suggest protecting the outer side of the ilium during surgery. LEVEL OF EVIDENCE: Level III.

The influence of musculoskeletal forces on the growth of the prenatal cortex in the ilium: a finite element study.

Remodelling and adaptation of bone within the pelvis is believed to be influenced by the mechanical strains generated during locomotion. Variation in the cortical bone thickness observed in the prenatal ilium has been linked to the musculoskeletal loading associated with in utero movements; for example the development of a thicker gluteal cortex is a possible response to contractions of the gluteal muscles. This study examines if the strains generated in the prenatal iliac cortex due to musculoskeletal loading in utero are capable of initiating bone remodelling to either maintain homeostasis or form new bone. Computational modelling techniques were used firstly to predict the muscle forces and resultant joint reaction force acting on the pelvis during a range of in utero movements. Finite element analyses were subsequently performed to calculate the von Mises strains induced in the prenatal ilium. The results demonstrated that strains generated in the iliac cortex were above the thresholds suggested to regulate bone remodelling to either maintain homeostasis or form new bone. Further simulations are required to investigate the extent to which the heterogeneous cortex forms in response to these strains (i.e., remodelling) or if developmental bone modelling plays a more pivotal role.

Integrating Growth Variability of the Ilium, Fifth Lumbar Vertebra, and Clavicle with Multivariate Adaptive Regression Splines Models for Subadult Age Estimation.

Subadult age estimation should rely on sampling and statistical protocols capturing development variability for more accurate age estimates. In this perspective, measurements were taken on the fifth lumbar vertebrae and/or clavicles of 534 French males and females aged 0-19 years and the ilia of 244 males and females aged 0-12 years. These variables were fitted in nonparametric multivariate adaptive regression splines (MARS) models with 95% prediction intervals (PIs) of age. The models were tested on two independent samples from Marseille and the Luis Lopes reference collection from Lisbon. Models using ilium width and module, maximum clavicle length, and lateral vertebral body heights were more than 92% accurate. Precision was lower for postpubertal individuals. Integrating punctual nonlinearities of the relationship between age and the variables and dynamic prediction intervals incorporated the normal increase in interindividual growth variability (heteroscedasticity of variance) with age for more biologically accurate predictions.

Quantitative anatomy of the ilium's primary ossification center in the human fetus.

PURPOSE: An understanding of the development of the ilium's primary ossification center may be useful in both determining the fetal stage and maturity, and for detecting congenital disorders. This study was performed to quantitatively examine the ilium's primary ossification center with respect to its linear, planar and volumetric parameters. MATERIALS AND METHODS: Using methods of CT, digital-image analysis and statistics, the size of the ilium's primary ossification center in 42 spontaneously aborted human fetuses of crown-rump length (CRL) ranged from 130 to 265 mm (aged 18-30 weeks) was studied. RESULTS: With no sex and laterality differences, the best fit growth dynamics for the ilium's primary ossification center was modelled by the following functions: y = - 63.138 + 33.413 × ln(CRL) ± 1.609 for its vertical diameter, y = - 59.220 + 31.353 × ln(CRL) ± 1.736 for its transverse diameter, y = - 105.681 + 1.137 × CRL ± 16.035 for its projection surface area, and y = 478.588 + 4.035 × CRL ± 14.332 for its volume. The shape of the ilium's primary ossification center did not change over the study period, because its transverse -to- vertical diameter ratio was stable at the level of 0.94 ± 0.07. Conclusions The size of the ilium's primary ossification center displays neither sex nor laterality differences. The ilium's primary ossification center grows logarithmically with respect to its vertical and transverse diameters, and linearly with respect to its projection surface area and volume. The shape of the ilium's primary ossification center does not change throughout the examined period. The obtained quantitative data of the ilium's primary ossification center is considered normative for respective prenatal weeks and may contribute to the prenatal ultrasound diagnostics of congenital defects.

Increased bone matrix mineralization in treatment-naïve children with inflammatory bowel disease.

Inflammatory bowel disease (IBD) affects many organ systems including the skeleton. In children with IBD, bone mineral density (BMD) and bone turnover are frequently low. Disturbances in bone mineralization density distribution (BMDD) are linked to alterations in bone material strength; however, BMDD has not previously been reported in children with chronic inflammatory disorders. The aim of this study was to characterize BMDD based on quantitative backscatter electron imaging in cancellous (Cn.) and cortical (Ct.) compartments from trans-iliac biopsy samples from a cohort of 20 treatment-naïve children at the time of their IBD diagnosis (12 males, mean age 14.5±2.3years). The outcomes were compared to pediatric reference BMDD data and correlation with revisited biochemical and histomorphometric outcomes was analyzed. BMDD in treatment-naïve children with IBD was shifted toward higher calcium concentrations compared to reference: (i) In cancellous bone, the most frequent calcium concentration (Cn.CaPeak+2.8%, p=0.004) and the portion of highly mineralized bone (Cn.CaHigh+52%, p=0.009) were increased. (ii) In cortical bone, the mineralization heterogeneity (Ct.CaWidth+17.0%, p=0.001) and Ct.CaHigh (+30.4%, p=0.006) were increased. (iii) Furthermore, significant correlations with serum alkaline phosphatase (ALP), bone-specific alkaline phosphatase (bsALP), and urinary crosslinked N-telopeptide of type I collagen (uNTX) were observed: the higher CaMean (the average calcium concentration), CaPeak and CaHigh, the lower were ALP, bsALP, and uNTX (p-value from <0.001 to 0.05). Children with treatment-naïve IBD have decreased bone turnover leading to a higher bone matrix mineralization density, findings which may contribute to compromised bone strength.

Validation methods of Fazekas and Kósa and Molleson and Cox for age estimation of the ilium in Western Mediterranean non-adult population: proposal of new regression formulas.

The purpose of this study is to test the applicability of the age estimation methods of Fazekas and Kósa [1] and Molleson and Cox [2] in Western Mediterranean non-adults and to develop accurate and rapidly applied formulas for their age estimation, using a sample of 149 non-adults of known sex and age from the cemetery of San José in Granada (Spain). Measurements have been taken of the maximum length and width of each ilium for application of the formulas of Fazekas and Kósa [1] and Molleson and Cox [2]. There has been no significant intra- or inter-examiner variation in measurements. The documented age of the individuals has been underestimated with the Fazekas and Kósa method and overestimated with Molleson and Cox. Based on these findings, new formulas are proposed for the age estimation of non-adults in Western Mediterranean populations.

Apophyseal Ossification of the Iliac Crest in Forensic Age Estimation: Computed Tomography Standards for Modern Australian Subadults.

This study contrasts the ontogeny of the iliac crest apophysis using conventional radiography and multislice computed tomography (MSCT), providing probabilistic information for age estimation of modern Australian subadults. Retrospective abdominopelvic MSCT data acquired from 524 Australian individuals aged 7-25 and surveillance radiographs of adolescent idiopathic scoliosis patients included in the Paediatric Spine Research Group Progression Study (n = 531) were assessed. Ossification scoring of pseudo-radiographs and three-dimensional (3D) volume-rendered reconstructions using Risser (1958) quantitative descriptors indicate discrepancies in age estimates, stage allocation, and conflicting morphological progression. To mitigate visualization limitations associated with two-dimensional radiographs, we provide and validate a modified 3D-MSCT scoring tier of ossification, demonstrating complete fusion between 17.3-19.2 and 17.1-20.1 years in males and females. Legal demarcation for doli incapax presumption and age of majority (18 years) can be achieved using probability estimates from a fitted cumulative probit model for apophyseal fusion using the recalibrated standards.

Bidimensional Data Allow for Better Age Estimation on Immature Specimens than Unidimensional Data: A Preliminary Study on the Ilium.

Most biometric age estimation methods used in anthropological and forensic science for juveniles are based on unidimensional measurements (length or width). Here, a new method using bidimensional data was tested. A 3D morphometric analysis was performed on 108 CT scans of ilium bone of juveniles (from 20 gestational weeks to 12 years old). The sample was divided into training and validation groups. Best predictors were determined by comparing the efficiency of each variable (length, width, area, and module: a product of length and width). We established linear and polynomial regressions for each parameter for both sides. Applying the equations to the validation sample showed no significant difference between real and predicted ages. For age estimation, the area and module parameters yielded better results than unidimensional measurements. The results from this preliminary study were highly conclusive, and it would be interesting to extend the work, covering larger samples, and other bones.

Age estimation based on pelvic ossification using regression models from conventional radiography.

To establish regression models for age estimation from the combination of the ossification of iliac crest and ischial tuberosity. One thousand three hundred and seventy-nine conventional pelvic radiographs at the West China Hospital of Sichuan University between January 2010 and June 2012 were evaluated retrospectively. The receiver operating characteristic analysis was performed to measure the value of estimation of 18 years of age with the classification scheme for the iliac crest and ischial tuberosity. Regression analysis was performed, and formulas for calculating approximate chronological age according to the combination developmental status of the ossification for the iliac crest and ischial tuberosity were developed. The areas under the receiver operating characteristic (ROC) curves were above 0.9 (p < 0.001), indicating a good prediction of the grading systems, and the cubic regression model was found to have the highest R-square value (R (2) = 0.744 for female and R (2) = 0.753 for male). The present classification scheme for apophyseal iliac crest ossification and the ischial tuberosity may be used for age estimation. And the present established cubic regression model according to the combination developmental status of the ossification for the iliac crest and ischial tuberosity can be used for age estimation.

Computed tomography evaluation of the iliac crest apophysis: age estimation in living individuals.

Determination of the ossification properties of the iliac apophysis is important not only in the clinical evaluation of patients undergoing orthopedic surgery but also in age estimation studies for forensic purposes. The literature includes both anthropological and radiological (conventional radiography, ultrasonography, and magnetic resonance imaging modalities) investigations of the different staging systems used for these purposes. In this study, we assessed the utility of computed tomography (CT) of the iliac crest apophysis in estimating forensic age. CT scans of the iliac crest apophysis of 380 patients (187 females, 193 males, and 10-29 years of age) were evaluated according to the four-stage system. Further subclassification did not give data properly due to the reference length measurement of the iliac wing with CT. Thus, in our series, stage 2 was first seen in 12 years of age and stage 3 in those 14 years of age in both sexes and on both sides of the pelvis. Stage 4 was first seen in 17 years of both sexes but only on the right side; on the left side, it appeared in females 18 years of age and in males 17 years of age. Present data was found consistent with previous pelvic radiographic findings. First seen ages for stage 2 and 3 are 12 and 14 years respectively which presented valuable information for legally important age thresholds. However, disadvantages of CT, including high-dose radiation exposure to gonads, the difficulty of evaluating the iliac crest, and the age boundary of 17 years, could make this method infeasible, as compared with hand wrist and pelvic radiographic methods. CT of the iliac crest has probably a greater utility where preexisting CT scans of the pelvic region are available, and it may be considered as a supportive method for age-estimation purposes.

Forensic age estimation through evaluation of the apophyseal ossification of the iliac crest in Western Chinese.

The criminal age estimation procedures have gained greatest significance to date, a reliable age diagnostics may depend on data of skeletal maturation from different socioeconomic status. In order to establish the iliac crest apophysis as a possible criterion for forensic age estimation in a different socioeconomic status, and to examine the pace of ossification for the iliac crest apophysis in Western Chinese, one thousand seven hundreds and seventy-seven conventional pelvic radiographs relating to West China Han group routinely taken between January 2010 and June 2012 have been sighted. The data was analysed with separation of the sexes. The results indicated that stage 2a was last observed in females at the age of 17.00 and in males at the age of 18.01, stage 3a was first achieved in females at the age of 14.46 and in males at the age of 15.31, stage 4 was observed between 17.95 and 25.98 years for male and between 18.36 and 25.95 years for female. By comparison with previous studies, our research indicated that Western Chinese presents a delaying development for the iliac crest apophysis. Furthermore, the present study with eight stages of ossification for the iliac crest offers a valuable alternative method of estimation of 18 years of age for Western Chinese.

Shape, size, and maturity trajectories of the human ilium.

Morphological traits of the ilium have consistently been more successful for juvenile sex determination than have techniques applied to other skeletal elements, however relatively little is known about the ontogeny and maturation of size and shape dimorphism in the ilium. We use a geometric morphometric approach to quantitatively separate the ontogeny of size and shape of the ilium, and analyze interpopulation differences in the onset, rate and patterning of sexual dimorphism. We captured the shape of three traits for a total of 191 ilia from Lisbon (Portugal) and London (UK) samples of known age and sex (0-17 years). Our results indicate that a) there is a clear dissociation between the ontogeny of size and shape in males and females, b) the ontogeny of size and shape are each defined by non-linear trajectories that differ between the sexes, c) there are interpopulation differences in ontogenetic shape trajectories, which point to population-specific patterning in the attainment of sexual dimorphism, and d) the rate of shape maturation and size maturation is typically higher for females than males. Male and female shape differences in the ilium are brought about by trajectory divergence. Differences in size and shape maturation between the sexes suggest that maturity may confound our ability to discriminate between the sexes by introducing variation not accounted for in age-based groupings. The accuracy of sex determination methods using the ilium may be improved by the use of different traits for particular age groups, to capture the ontogenetic development of shape in both sexes.

Childhood cortical porosity is related to microstructural properties of the bone-muscle junction.

Childhood cortical porosity is attributable to giant asymmetrical drifting osteonal canals that arise predominantly along the primary-secondary bone interface (PSBI). Bone from the external iliac crest cortex of 92 subjects aged 0 to 25 years was examined histomorphometrically for differences in microstructural properties between primary and secondary bone that might account for features of drifting osteonal canals. Primary compared with secondary bone showed greater numbers of osteocyte lacunae, thinner collagen lamellae, and a scaffold of elastic perforating fibers (PFs). The greater number of osteocyte lacunae compounded by known perilacunar strain amplification and the presence of elastic PFs are expected to be associated with greater bone tissue strain in primary than in secondary bone and thus with strain gradients at the PSBI. Strain gradients may lead local osteocytes to originate resorption canals and to promote transverse drift of the resorption front into lower-strain secondary bone, thus creating giant asymmetrical drifting osteonal canals that remodel primary to secondary bone. PFs extended from muscle fibers through periosteum and primary bone to the PSBI, where they were resorbed by origination of drifting canals. Growth modeling by periosteal osteoblasts proceeds in the gaps between PFs. Through the direct connection between muscle and the PSBI via PFs, muscle forces may influence not only modeling by raising strain but also remodeling of primary to secondary bone by increasing strain gradients at the PSBI. With reduction in primary bone width after the mid-teens, numbers of drifting canals and porosity declined. Differences in microstructural properties between primary and secondary bone are expected to generate strain gradients at the PSBI that contribute to site, transverse drift, asymmetry and large size of drifting canals, and, hence, to cortical porosity. Cortical porosity in children is a physiological feature of bone growth in width. Advisability of therapeutic intervention remains to be defined.

Evolution of the ischio-iliac lordosis during natural growth and its relation with the pelvic incidence.

PURPOSE: Human fully upright ambulation, with fully extended hips and knees, and the body's center of gravity directly above the hips, is unique in nature, and distinguishes humans from all other mammalians. This bipedalism is made possible by the development of a lordosis between the ischium and ilium; it allows to ambulate in this unique bipedal manner, without sacrificing forceful extension of the legs. This configuration in space introduces unique biomechanical forces with relevance for a number of spinal conditions. The aim of this study was to quantify the development of this lordosis between ischium and ilium in the normal growing and adult spine and to evaluate its correlation with the well-known clinical parameter, pelvic incidence. METHODS: Consecutive series of three-dimensional computed tomography scans of the abdomen of 189 children and 310 adults without spino-pelvic pathologies were used. Scan indications were trauma screening or acute abdominal pathology. Using previously validated image processing techniques, femoral heads, center of the sacral endplate and the axes of the ischial bones were semi-automatically identified. A true sagittal view of the pelvis was automatically reconstructed, on which ischio-iliac angulation and pelvic incidence were calculated. The ischio-iliac angle was defined as the angle between the axes of the ischial bones and the line from the midpoint of the sacral endplate to the center of the femoral heads. RESULTS: A wide natural variation of the ischio-iliac angle (3°-46°) and pelvic incidence (14°-77°) was observed. Pearson's analysis demonstrated a significant correlation between the ischio-iliac angle and pelvic incidence (r = 0.558, P < 0.001). Linear regression analysis revealed that ischio-iliac angle, as well as pelvic incidence, increases during childhood (+7° and +10°, respectively) and becomes constant after adolescence. CONCLUSIONS: The development of the ischio-iliac lordosis is unique in nature, is in harmonious continuity with the highly individual lumbar lordosis and defines the way the human spine is biomechanically loaded. The practical parameter that reflects this is the pelvic incidence; both values increase during growth and remain stable in adulthood.

Magnetic resonance imaging of the iliac crest: age estimation in under-20 soccer players.

Age assessment of living individuals represents a valuable tool in both forensic medicine and sports medicine. In soccer, age-related tournaments play an important role in guaranteeing equal chances to the competitors. However, age estimations in this field should not rely on imaging methods that include exposure to radiation. Therefore, the present study investigates the possibilities of magnetic resonance imaging (MRI) of the iliac crest apophysis for the purpose of evaluating skeletal maturation in under-20 (U-20) soccer players. To this end, gradient echo 3D sequences of the whole pelvis of 152 male tournament soccer players between 18 and 22 years of age were prospectively evaluated. A four stage classification system was applied for the assessment of the apophyseal ossification. Reliable stage determination was possible in all cases. Further sub-classification did not appear feasible due to the limitations of MRI. Analysis of the statistical parameters showed that age medians increased steadily from stage to stage. However, they did not allow for further differentiation of skeletal maturity in the cohort studied. Thus, MRI of the iliac crest appears to be generally suitable in age diagnostics of living individuals, but further investigations, especially in a cohort of individuals aged between 10 and 20 years, are needed in order to establish this method as novel criterion in sports or forensic medicine.

Growth of the human ilium: the anomalous sacroiliac junction.

Despite the major anatomical importance of the human ilium in medicine and forensic investigations, little is understood about its pattern of growth. This study was conducted to investigate the changes in the surface area of the human ilium from birth through to adolescence in 80 human ilia. A photographic image of the pelvic surface of each bone was taken and examined using an image quantification package. The surface areas of four regions of interest were quantified: the auricular, post-auricular (PA), iliac fossa, and whole pelvic surface of the ilium. The results highlight a rapid increase in surface area for all regions in the first few years after birth which continues, albeit at a slower rate, until ∼4 years of age when the rate of growth is further reduced. Although the ilium and its various components continue to grow between 5 years and puberty, the rate of growth is markedly reduced until puberty when growth of the pelvis again increases. Interestingly, analysis of the differential growth of the auricular region compared with the PA region throughout development suggests that the PA region exhibits more advanced growth. This may indicate that its role in structural development for the purposes of preparation and maintenance of bipedal stance and locomotion may have been previously poorly understood.

Cameriere's approach modified for pelvic radiographs: a novel method to assess apophyseal iliac crest ossification for the purpose of forensic age diagnostics.

According to a modified method originally developed by Cameriere et al. (Int J Legal Med 120:143-146, 2006; J Forensic Sci 52:1151-1155, 2007; Forensic Sci Int 174:59-62, 2008; Forensic Sci Int 174:178-181, 2008; Forensic Sci Int 193:128.e1-128.e6, 2009), the suitability of the iliac crest apophysis (ICA) for the purpose of forensic age estimation in living individuals was investigated by means of area measurements in 643 pelvic radiographs of patients aged between 10 and 30 years. The area of the ossification centre(s) of the iliac crest and the area of the iliac wing (IW) were determined by manual segmentation. In 116 cases, area measurements were possible. ICA/IW ratios were calculated and used for regression analyses, yielding different regression equations. Depending on sex, pelvic side and ratio considered, R (2) ranged between 0.20 and 0.38 and the standard error of the estimate, between 1.91 and 2.00 years. No statistical significant differences were found between the right and the left pelvic sides. In conclusion, this method is potentially applicable for forensic age estimation in living individuals. However, further studies under more standardised conditions and with higher case numbers are needed in order to decide whether the iliac crest apophysis might become suitable for routine age diagnostics.

Ontogeny of size and shape sexual dimorphism in the ilium: a multislice computed tomography study by geometric morphometry.

We studied sexually dimorphic differences in the ilium using geometric morphometric analysis of 10 osteometric landmarks recorded by multislice computed tomography, based on three-dimensional reconstructions of 188 children (95 boys, 93 girls) of mixed origins living in the area of Toulouse, southern France, and ranging in age from 1 to 18 years. We used geometric morphometrics methodology first to test sexual dimorphism in size (centroid size) and shape (Procrustes residuals) and second to examine patterns of shape change with age (development) and size change with age (growth). On the basis of statistical significance testing, the ilium shape became sexually dimorphic at 11 years of age, although visible shape differences were observed as early as 1 year of age. There was no statistically significant difference in size between sexes. Trajectories of shape (development) and size (growth) differed throughout ontogeny and between sexes.

The iliac crest in forensic age diagnostics: evaluation of the apophyseal ossification in conventional radiography.

Due to the increasing significance of forensic age estimations in the age of globalisation, novel radiographic criteria besides clavicles and hand bones may provide additional certainty for forensic age expertises. The present study analyses the suitability of the iliac crest apophysis by means of 643 pelvic radiographs of patients between 10 and 30 years of age. Retrospective assessments were carried out according to the forensically established classification and sub-classification systems modified after Kreitner et al. (Rofo 166(6):481-486, 1997) and Kellinghaus et al. (Int J Legal Med 124(4):321-325, 2010). The basic ossification stages range from 1 to 4, and the sub-stages of stage 2 and 3 range from a to c. While stage 3c was first achieved at the age of 15 by both sexes, stage 4 was first observed in females at the age of 16 and in males at the age of 17. This indicates the possibility of a valid diagnosis of both the age of 14 and the age of 16 years which represent legally relevant age thresholds in numerous countries. Applied as targeted radiography on the iliac crest, the exposure to radiation would range between other radiographic techniques recently applied. Therefore, the iliac crest apophysis appears principally suitable as novel possible criterion for forensic age estimation in the living. However, for the establishment of the iliac crest apophysis in routine diagnostics, further studies are needed focussing on the comparison of different grading systems and different radiological techniques.

The Risser sign for forensic age estimation in living individuals: a study of 643 pelvic radiographs.

Due to increasing international migratory movements, forensic age estimations of living individuals in criminal proceedings are gaining increasing significance for forensic physicians and radiologists involved in delivering expert opinions. The present study examines the suitability of the radiologically well-known Risser sign grading as a possible new criterion in forensic age diagnostics. For this purpose, anteroposterior pelvic radiographs of 643 patients aged between 10 and 30 years were retrospectively evaluated by means of two different Risser sign grading systems (US and French), each with 5 stages. The left and right sides of the pelvis were assessed separately. The data was analyzed with separation of the sexes. Reliable Risser sign determination was possible in 566 cases. In both sexes, stage 4 of both the US and the French grading systems was predominantly first noted at age 14 years. In the US grading system, stage 5 was also first achieved at age 14 years in the majority of both sexes. In the French grading system, females manifested stage 5 at a minimum of 16 years, whereas in males it was first observed at 17 years. As to the nature of iliac crest maturation, interesting deviations were observed at stages 1 and 5, raising doubts about Risser's ossification process. To conclude, both Risser sign grading systems are suitable for forensic age diagnostics, especially to determine whether the 14th year of life has been completed or not. The French Risser sign system additionally allows for statements as to the completion of the 16th year of age.