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Objective: We sought to examine associations between height gain across childhood and adolescence with hip shape in individuals aged 60-64 years from the Medical Research Council National Survey of Health and Development, a nationally representative British birth cohort., Methods: Height was measured at ages 2, 4, 6, 7, 11 and 15 years, and self-reported at age 20 years. 10 modes of variation in hip shape (HM1-10), described by statistical shape models, were previously ascertained from DXA images taken at ages 60-64 years. Associations between (1) height at each age; (2) Super-Imposition by Translation And Rotation (SITAR) growth curve variables of height size, tempo and velocity; and (3) height gain during specific periods of childhood and adolescence, and HM1-10 were tested., Results: Faster growth velocity was associated with a wider, flatter femoral head and neck, as described by positive scores for HM6 (regression coefficient 0.014; 95% CI 0.08 to 0.019; p<0.001) and HM7 (regression coefficient 0.07; 95% CI 0.002 to 0.013; p=0.009), and negative scores for HM10 (regression coefficient -0.006; 95% CI -0.011 to 0.00, p=0.04) and HM2 (males only, regression coefficient -0.017; 95% CI -0.026 to -0.09; p<0.001). Similar associations were observed with greater height size and later height tempo. Examination of height gains during specific periods of childhood and adolescence identified those during the adolescence period as being most consistently associated., Conclusion: Our analyses suggest that individual growth patterns, particularly in the adolescent period, are associated with modest variations in hip shape at 60-64 years, which are consistent with features seen in osteoarthritis., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY. Published by BMJ.)

Context: Among patients with type 1 diabetes (T1D), the risk of hip fracture is up to 6-fold greater than that of the general population. However, the cause of this skeletal fragility remains poorly understood., Objective: To assess differences in hip geometry and imaging-based estimates of bone strength between youth with and without T1D using dual-energy x-ray absorptiometry (DXA)-based hip structural analysis., Design: Cross-sectional comparison., Participants: Girls ages 10 to 16 years, including n = 62 with T1D and n = 61 controls., Results: The groups had similar age, bone age, pubertal stage, height, lean mass, and physical activity. Bone mineral density at the femoral neck and total hip did not differ in univariate comparisons but was lower at the femoral neck in T1D after adjusting for bone age, height, and lean mass. Subjects with T1D had significantly lower cross-sectional area, cross-sectional moment of inertia, section modulus, and cortical thickness at the narrow neck, with deficits of 5.7% to 10.3%. Cross-sectional area was also lower at the intertrochanteric region in girls with T1D. Among those T1D subjects with HbA1c greater than the cohort median of 8.5%, deficits in hip geometry and strength estimates were more pronounced., Conclusions: DXA-based hip structural analysis revealed that girls with T1D have unfavorable geometry and lower estimates of bone strength at the hip, which may contribute to skeletal fragility and excess hip fracture risk in adulthood. Higher average glycemia may exacerbate effects of T1D on hip geometry., (• The Author(s) 2020. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Female gymnasts have been evidenced to experience sport-specific growth, of which broad shoulders and narrow hips are common characteristics. In addition to being a central component of handstand performance, postural control mechanisms, including whole-body and lumbo-pelvic stability, have been identified as risk factors for overuse spinal pathology. The study aimed to develop a fundamental understanding of musculoskeletal growth and postural control responses of female artistic gymnasts in order to extend longitudinal insights into overuse spinal pathology risk. Whole-body anthropometric measures were collected for 12 competitive female gymnasts (age at recruitment: nine to 15 years) at three time points across a 12 month period. Musculoskeletal growth was partially defined as the rate of bicristal-to-biacromial breadth ratio development, and informed shoulder- and pelvis-dominant growth sub-groups. Kinematic and kinetic indicators of postural control were determined for a total of 700 handstand trials. The shoulder-dominant (gymnastics-specific) growth group was found to have significantly greater biomechanical risk for general stability ( p  < 0.001) than the pelvis-dominant group. Significantly greater lumbo-pelvic risk was demonstrated for the pelvis-dominant group ( p  < 0.001). Extended idiosyncratic examination of proportional sport-specific growth measures alongside multi-faceted risk monitoring was advocated for the effective development of future overuse pathology prevention protocols.

Given GDF5 involvement in hip development, and osteoarthritis (OA) and developmental hip dysplasia (DDH) risk, here we sought to assess the role(s) of GDF5 and its regulatory sequence on the development of hip morphology linked to injury risk. The brachypodism (bp) mouse, which harbors a Gdf5 inactivating mutation, was used to survey how Gdf5 loss of function impacts the development of hip morphology. Two transgenic Gdf5 reporter BAC lines were used to assess the spatiotemporal expression of Gdf5 regulatory sequences. Each BAC line was also used to assess the functional roles of upstream and downstream sequence on hip morphology. bp/bp mice had shorter femora with smaller femoral heads and necks as well as larger alpha angles, smaller anterior offsets, and smaller acetabula, compared to bp/+ mice (p<0.04). Regulatory sequences downstream of Gdf5 drove strong prenatal (E17) expression and low postnatal (6 months) expression across regions of femoral head and acetabulum. Conversely, upstream regulatory sequences drove very low expression at E17 and no detectable expression at 6 months. Importantly, downstream, but not upstream Gdf5 regulatory sequences fully restored all the key morphologic features disrupted in bp/bp mice. Hip morphology is profoundly affected by Gdf5 absence, and downstream regulatory sequences mediate its effects by controlling Gdf5 expression during development. This downstream region contains numerous enhancers harboring risk variants related to hip OA, DDH, and dislocation. We posit that subtle alterations to morphology driven by changes in downstream regulatory sequence underlie this locus' role in hip injury risk., Competing Interests: The authors have declared that no competing interests exist.

Throughout development, the vascular supply to the proximal femur and acetabulum undergoes a series of changes during which it is susceptible to injury. Before age 3 months, the ligamentum teres and lateral epiphyseal arteries are the dominant supply to the developing head. The dominant supply shifts to the lateral epiphyseal vessels by age 18 months. The distinct metaphyseal and epiphyseal circulations of the adult proximal femur form in adolescence when an increasingly rich metaphyseal circulation supplies the subphyseal region, terminating at the physeal plate. The acetabular blood supply derives from two independent systems, with the dominance of each changing throughout maturity. Most descriptions of the vascular contributions to the proximal femur and acetabulum have been gross anatomic and histologic studies. Advanced imaging studies (eg, CT angiography, perfusion MRI) have added to our understanding of the vascular anatomy of the proximal femur and acetabulum, its changes throughout development, and its clinical implications.

The thoracic-to-hip circumference ratio (THR) is an anthropometric marker recently described as a predictor of type 2 diabetes. In this study, we performed a genome-wide association study (GWAS) followed by confirmatory analyses to identify genetic markers associated with THR. A total of 7,240 Korean subjects (4,988 for the discovery stage and 2,252 for the confirmatory analyses) were recruited for this study, and genome-wide single nucleotide polymorphism (SNP) genotyping of the initial 4,988 individuals was performed using Affymetrix Human SNP array 5.0. Linear regression analysis was then performed to adjust for the effects of age, sex, and current diabetes medication status on the THR of the study subjects. In the initial discovery stage, there was a statistically nominal association between minor alleles of SNP markers on chromosomes 4, 8, 10, and 12, and THR changes (p < 5.0 × 10-6). The subsequent confirmatory analyses of these markers, however, only detected a significant association between two SNPs in the HECTD4 gene and decreased THRs. Notably, this association was detected in male (rs11066280: p = 1.14 × 10-2; rs2074356: p = 1.10 × 10-2), but not in female subjects. Meanwhile, the combined results from the two analyses (initial and confirmatory) indicated that minor alleles of these two intronic variants exhibited a significant genome-wide association with decreased THR in the male subjects (n = 3,155; rs11066280: effect size = -0.008624, p = 6.19 × 10-9; rs2074356: effect size = -0.008762, p = 1.89 × 10-8). Furthermore, minor alleles of these two SNPs exhibited protective effects on patients' risks for developing type 2 diabetes. In conclusion, we have identified two genetic variations in HECTD4 that are associated with THR, particularly in men.

Pelvic obliquity is a common finding in adolescents with cerebral palsy, however, there is little agreement on its measurement or relationship with hip development at different gross motor function classification system (GMFCS) levels. The purpose of this investigation was to study these issues in a large, population-based cohort of adolescents with cerebral palsy at transition into adult services. The cohort were a subset of a three year birth cohort (n = 98, 65M: 33F, with a mean age of 18.8 years (14.8 to 23.63) at their last radiological review) with the common features of a migration percentage greater than 30% and a history of adductor release surgery. Different radiological methods of measuring pelvic obliquity were investigated in 40 patients and the angle between the acetabular tear drops (ITDL) and the horizontal reference frame of the radiograph was found to be reliable, with good face validity. This was selected for further study in all 98 patients. The median pelvic obliquity was 4° (interquartile range 2° to 8°). There was a strong correlation between hip morphology and the presence of pelvic obliquity (effect of ITDL on Sharpe's angle in the higher hip; rho 7.20 (5% confidence interval 5.59 to 8.81, p < 0.001). This was particularly true in non-ambulant adolescents (GMFCS IV and V) with severe pelvic obliquity, but was also easily detectable and clinically relevant in ambulant adolescents with mild pelvic obliquity. The identification of pelvic obliquity and its management deserves closer scrutiny in children and adolescents with cerebral palsy., (©2015 The British Editorial Society of Bone & Joint Surgery.)

Background and Objective: There is paucity of evidence in southeastern Europe and Kosovo regarding dairy products consumption and association with bone mineral density (BMD). Therefore, the objective of present study was to assess calcium intake and dairy products consumption and to investigate relationship with total hip BMD in a Kosovo women sample., Methods: This cross-sectional study included a sample of 185 women divided into respective groups according to total hip BMD. All the study participants completed a food frequency questionnaire and underwent dual-energy X-ray absorptiometry (DEXA) to estimate BMD. Nonparametric tests were performed to compare characteristics of the groups., Results: The average dietary calcium intake was 818.41 mg/day. Only 16.75% of the subjects met calcium recommended dietary reference intakes (DRIs). There were no significant differences between low BMD group and normal BMD group regarding average dietary calcium intake, but it was significantly higher in BMDT3 subgroup than in BMDT2 and BMDT1 subgroups., Conclusions: The results of this study demonstrate significant relationship of daily dietary calcium intake with upper BMD tertile. Further initiatives are warranted from this study to highlight the importance of nutrition education.

Objective: To study the results of the total hip arthroplasty (THA) in the treatment of developmental dysplasia of the hip (DDH) with severe osteoarthritis in adults., Methods: From March 2004 to February 2011, 29 patients (32 hips) with DDH were treated by THA with an cementless cup. There were 11 males and 18 females,with an average age of 52.6 years (ranging from 37 to 73 years). Unilateral DDH occurred in 26 patients and bilateral DDH occurred in 3 patients. Based on the Crowe classification, there were 18 hips in 17 patients of type I ,7 hips in 6 patients of type II, 4 hips in 3 patients of type III, 3 hips in 3 patients of type IV. Except for 3 patients with bilateral DDH, the other patients' ill lower limbs were 1 to 6 cm shorter than the healthy lower ones., Results: All the patients were followed up,and the duration ranged from 8 months to 5.3 years(averaged 3.7 years) without infection, dislocation, and sciatic nerves injury after the operation. One patient with proximal femoral fracture, intraoperation used wire binding, after 4 years of follow-up, fracture healed without evidence of prosthesis loosening. All grafts and subtrochanteric osteotomy healing were achieved. In 21 patients, the pain was completely relieved and the function of the hip joints was good. Five patients still had mild limping, but reduced significantly than preoperation. In 3 patients, the ill lower limbs were more than 1 cm shorter than the healthy lower ones and the other patients' ill lower limbs were less than 1 cm shorter than the healthy lower ones. Two patients' lower limbs were lengthened 4 to 5 cm. The Harris scores were 43.6 +/- 7.1 preoperatively and 86.7 +/- 5.3 postoperatively (P < 0.05)., Conclusion: THA with deepening the medial wall of the acetabulum at the true acetabulum, according to different characteristics of Crowe classification, using different operation program, cementless cup in adult could obtain favorable results.

Background: We investigated relationships between early growth and proximal femoral geometry at age 6 y in a prospective population-based cohort, the Southampton Women's Survey., Methods: In 493 mother-offspring pairs, we assessed linear size using high-resolution ultrasound at 11, 19, and 34 wk gestation (femur length) and at birth and 1, 2, 3, 4, and 6 y (crown-heel length/height). SD scores were created and conditional regression modeling generated mutually independent growth variables. Children underwent hip dual-energy X-ray absorptiometry (DXA) at 6 y; hip structure analysis software yielded measures of geometry and strength., Results: There were strong associations between early linear growth and femoral neck section modulus (Z) at 6 y, with the strongest relationships observed for femur growth from 19 to 34 wk gestation (β = 0.26 cm(3)/SD, P < 0.0001), and for height growth from birth to 1 y (β = 0.25 cm(3)/SD, P < 0.0001) and 1 to 2 y (β = 0.33 cm(3)/SD, P < 0.0001), with progressively weaker relationships over years 3 (β = 0.23 cm(3)/SD, P = 0.0002) and 4 (β = 0.10 cm(3)/SD, P = 0.18)., Conclusion: These results demonstrate that growth before age 3 y predicts proximal femoral geometry at 6 y old. These data suggest critical periods in which there is capacity for long-term influence on the later skeletal growth trajectory.

Adult articular cartilage (AC) has a well described multizonal collagen structure. Knowledge of foetal AC organisation and development may provide a prototype for cartilage repair strategies, and improve understanding of structural changes in developmental diseases such as osteochondrosis (OC). The objective of this study was to describe normal development of the spatial architecture of the collagen network of equine AC using 1.5 T magnetic resonance imaging (MRI) and polarised light microscopy (PLM), at sites employed for cartilage repair studies or susceptible to OC. T2-weighted fast-spin echo (FSE) sequences and PLM assessment were performed on distal femoral epiphyses of equine foetuses, foals and adults. Both MRI and PLM revealed an early progressive collagen network zonal organisation of the femoral epiphyses, beginning at 4 months of gestation. PLM revealed that the collagen network of equine foetal AC prior to birth was already organised into an evident anisotropic layered structure that included the appearance of a dense tangential zone in the superficial AC in the youngest specimens, with the progressive development of an underlying transitional zone. A third, increasingly birefringent, radial layer developed in the AC from 6 months of gestation. Four laminae were observed on the MR images in the last third of gestation. These included not only the AC but also the superficial growth plate of the epiphysis. These findings provide novel data on normal equine foetal cartilage collagen development, and may serve as a template for cartilage repair studies in this species or a model for developmental studies of OC.

The aim of this study was to determine the effects of hip circumference (HC) and height on diabetes incidence in non-diabetic first-degree relatives (FDRs) of patients with type 2 diabetes. A total of 1,092 (254 men and 838 women) non-diabetics FDRs ≥ 30 years old in 2003-2005 were followed through 2010 for the occurrence of type 2 diabetes. At baseline and through follow-ups, participants were underwent a standard 75 g 2-h oral glucose tolerance test. The incidence of type 2 diabetes was 17.0 (95% CI: 13.7, 20.2) (13.0 men and 18.1 women) per 1,000 person-year based on 6,015 person-years of follow-up. Height was inversely associated with diabetes incidence. The age-, gender-, and waist-adjusted relative risk (95% CI) of diabetes was 0.54 (0.31, 0.93) for highest quartile of height and 0.59 (0.25, 1.37) for highest quartile of HC compared with lowest quartile. These data indicate that height was inversely associated with diabetes incidence, independently of gender among FDRs of patients with type 2 diabetes.

The evolution to a bipedal mode of locomotion was accompanied by a verticalization of the spine and a modification in the shape of the pelvis: horizontal curvature and sagittal rotation. Phylogenesis meets ontogenesis: flat bones in fetuses similar to the monkey, australopithecus features at birth and "human-like" features by 7 or 8years of age. These anatomical modifications explain the characteristics of human bipedalism: stable, economical, with hip and knee extension in the standing position with little lateral motion. Some pathologies induce a regression to a more archaic mode of bipedal locomotion., (Copyright © 2011 Elsevier Masson SAS and Éditions françaises de radiologie. All rights reserved.)

Housing, bedding, and summer cooling were management options evaluated. Holstein calves (42±2 kg of body weight) initially 2 to 5 d of age were managed in southwest Ohio in poly hutches or wire mesh pens in a curtain-sided nursery with no supplemental heat. Calves were fed milk replacer (27% crude protein, 17% fat fed at 0.657 kg of dry matter per calf daily), starter (20% crude protein dry matter, textured, fed free-choice), and water (free-choice). Measurements were for 56 d. In trial 1, 28 calves per treatment were bedded with straw and housed in either hutches or nursery pens. This trial was conducted from September to March; the average temperature was 8°C and ranged from -17 to 31°C. In trial 2a, 16 calves per treatment were managed in nursery pens bedded with straw, in nursery pens bedded with sand, or in hutches bedded with sand. This trial was conducted from May to September; the average temperature was 21°C and ranged from 7 to 33°C. In trial 2b, 26 calves per treatment were housed in nursery pens and bedded with straw. This trial was conducted from May to September; the average temperature was 22°C and ranged from 8 to 34°C. One treatment was cooled with fans between 0800 and 1700 h and the other was not. Data were analyzed as repeated measures in a completely randomized block design by trial, with calf as the experimental unit. In trial 3, air in the nursery and calf hutches used above was sampled 35 d apart for calves aged 5 and 40 d. Air in individual hutches on 2 commercial farms was sampled for 5- and 40-d-old calves for 2 hutch types. Air in the multi-calf hutches was sampled for calves of 75 and 110 d of age. Bacterial concentrations of air samples were analyzed (log10) as odds ratios by Proc Logistic in SAS software (SAS Institute Inc., Cary, NC); differences were declared at P<0.05. In trial 1, weight gain of calves in nursery pens was 6% greater and feed efficiency was 4% greater than that of calves in hutches. In trial 2a, weight gain and starter intake of calves in the nursery with straw bedding were greater and scouring was less than that in calves bedded with sand in the nursery or hutches. The relative humidity was greater in the hutches than in the nursery pens. In trial 2b, weight gain, feed efficiency, and hip width change were greater and breaths per minute were less for calves cooled with fans compared with calves that were not cooled. In trial 3, airborne bacteria concentrations were greater in the hutches than in the nursery pens. Straw bedding (vs. sand), nursery pens (vs. hutches), and summer daytime cooling with fans improved calf weight gain., (Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

Developmental dysplasia of the hip (DDH) is a well-known precipitator of hip osteoarthritis. An increase in body weight during the critical early postnatal growth period may alter joint contact, and thus alter hip development and influence joint health in adulthood. The objective of this study was to determine whether early postnatal body weight affected the course of hip development and the onset of osteoarthritis in a canine model of DDH. A longitudinal study, from birth to skeletal maturity, was conducted. Serial body weight, age at femoral head ossification onset, and femoral head coverage at 4 mo were measured. Presence and severity of degeneration at 8 mo were determined using necropsy and cartilage biochemistry. There was a negative association between birth weight and age at femoral head ossification onset; however, the association was likely due to skeletal maturity level rather than body weight per se. Lower birth weight subjects had greater femoral head coverage at 4 mo. Greater birth weight was associated with greater probability of moderate degenerative changes or macroscopic lesions at 8 mo. These results support the hypothesis that increased birth weight is sufficient to alter the course of hip development and result in measurable degenerative changes at adulthood.

The child's hip begins in intrauterine development as a condensation of mesoderm in the lower limb bud that rapidly differentiates to resemble the adult hip by eight weeks of life. The developmental instructions are transmitted through complicated cell signaling pathways. From eight weeks of development to adolescence, further growth of the hip is focused on differentiation and the establishment of the adult arterial supply. The postnatal growth of the child's hip is a product of concurrent acetabular and proximal femoral growth from their corresponding growth plates. Absence of appropriate contact between acetabulum and proximal femur yields an incongruent joint. Multiple disease processes may be understood in light of this growth process, including Legg-Calvé-Perthes disease and developmental dysplasia of the hip.

There are many angles measured on hip radiographs, but their prognostic value for hip development in patient with DDH is controversial. Our aim was to find out how the development of congenitally luxated hip could be predicted after reduction using Wiberg's CE angle and CE angle refined according to Ogata. 119 hips of 61 patients were retrospectively evaluated after reduction from 3 months of age until at least full osteomaturity. According to results of CE angles measurements good and poor hip development group were formed. Healthy hips of the patients with unilateral DDH were considered to be the control group. Negative linear trend of the curve connecting Wiberg's CE angle values measured within first postreductive years is a poor prognostic sign of hip development as are absolute negative values of refined CE angles. In cases where negative initial refined CE angles are combined with negative linear trend of Wiberg's CE angles prognosis is extremely poor. Both Wiberg's and Ogata's CE angle are of prognostic value regarding hip development and should be measured when evaluating AP radiographs of infant's hip.

A thorough knowledge of the normal growth and development of the hip, the causes of abnormal development, and the structural and functional changes that result from developmental hip dysplasia and dislocation provide needed information for treating these conditions. Ultrasonography, newborn screening, and radiographic evaluation are important diagnostic tools.

Skeletal loading during growth may be one way of increasing bone mass early in life. We hypothesized that children randomized to a jumping program (25 jumps/day from a 45-cm box, 5 days/week for 12 weeks) would have greater increases in hip and spine bone mineral content (BMC) and 4% distal tibia volumetric bone density than children randomized to the control group. Our secondary hypothesis was that jumping would not be as beneficial among peripubertal children as compared to prepubertal or pubertal children due to the relatively high growth rate that occurs during the peripubertal period. Fifty-four children (31 girls) ages 3-5, 7-8, 11-12, and 15-18 years were enrolled. We performed bone, anthropometric, and force plate measurements at baseline and 12 weeks. Twenty-four-hour diet recall and Tanner's self-report of pubertal development were completed at baseline. Jumpers had a lower calcium intake than nonjumpers at baseline (965 +/- 403 vs 1295 +/- 465 mg/day, P < 0.01), but the groups were otherwise similar. Overall, jumpers had greater increases in total body BMC (45.0 +/- 4.9 vs 29.4 +/- 5.3 g, P = 0.03) and regional dual energy x-ray absorptiometry leg BMC (19.8 +/- 2.6 vs 11.5 +/- 2.8 g, P = 0.03) than nonjumpers at all pubertal stages. However, the 4% distal tibia bone response to jumping appeared to be modified by pubertal stage, with the greatest bone benefit from jumping observed in pubertal children (interaction of jumping group by pubertal stage, P < 0.05, for both BMC and volumetric BMD). A similar pattern was observed for spine BMC (interaction, P = 0.10). We conclude that skeletal loading increases total body and leg BMC in children, but may not have a positive effect at sites that are predominantly trabecular bone during periods of rapid growth (i.e., peripubertal period).

The possibilities of MR imaging of the subcapital growth plate of the proximal femur were evaluated in 36 children with 58 normal hips. The most common presentation of the area of subcapital growth plate on MR images was that of a hypointense band on T1-weighted images and a hyperintense band on sequences using fat saturation. Thinning of the growth plate with age was observed and in the older subjects in this group the growth plate was no longer visible.

This article reports five types of persistent bony dysplasia in patients with congenital dislocation of the hip (CDH), suggests the pathogeneses, and discusses the treatment options. We consider the five types to be (1) maldirected acetabulum, (2) capacious acetabulum, (3) false acetabulum, (4) lateralized acetabulum, and (5) femoral deformity. The maldirected acetabulum persists when the acetabulum continues to face forward and laterally. The capacious acetabulum arises from joint instability; capsular laxity permits the proximal femur to slide within the acetabulum. The false acetabulum results from an ectopic fibrocartilaginous cavity in the pelvis created by the subluxated or dislocated femoral head.44 The lateralized acetabulum occurs with ossification of the cotyloid cavity from longstanding lateral subluxation or dislocation or premature closure of the triradiate cartilage. Femoral deformities include valgus and anteversion of the femoral neck, capital femoral physeal growth arrest, discrepancy between the greater trochanter and the femoral head, and femoral head asphericity. After clinical and radiographic evaluation, we believe that an understanding of the pathogeneses and types of dysplasia will facilitate appropriate treatment programs. Treatments consist of acetabular redirection, acetabular reconstruction, femoral osteotomies, and salvage procedures.

The authors investigated the development of the bony acetabulum in type IIa+ immature hips using ultrasound follow-up evaluation of the alpha and beta angle. The study comprised 900 hips in one-month old infants. In the initial ultrasound examination the alpha angle measured less than 60 degrees and the beta angle more than 55 degrees. In the second ultrasound examination at the age of two months a discrepancy between the bony and cartilaginous acetabular component was found in 15% of the hips, which means that the type IIa+ hips were transformed into the type IIa-. The infants with type IIa- hips had more than two risk factors for developmental dysplasia of the hip. The statistical relative risk was 17. These hips were treated with the Pavlik harness during two months on average. After treatment all hips had normal values the alpha and beta angles (more than 60 degrees and less than 55 degrees respectively). This study showed that each newborn and infant with a sonographically confirmed hip development disorder has to be included in the follow-up evaluation of acetabular development, which makes it possible to choose the most adequate therapeutic and prophylactic measures.

The aim of this paper was to relate time of the ossification center appearance and development stage according to Graf. Retrospective analysis included 4546 sonograms in children from 1 to 6 months of age and 1252 sonograms in 313 healthy newborns. An earlier appearance of the ossification center was found in females (7 weeks against 10 weeks of life in males). Statistically significant relationship was found between the delay in the ossification center appearance time and hip dysplasia. The delay exceeding 6 months is suggestive of serious pathology and complications in later stages of hip development.

We compared two similarly sized groups of sonographically unstable or decentered hips with comparable initial findings, both treated by standardized conservative primary treatment. The results show that an early definite diagnosis improves the prognosis. If built on a secure initial diagnosis rationally grounded and efficient conservative therapy can be initiated and followed through on. Since the treatment is started extremely early, the hip can benefit from the considerably greater potential for spontaneous development present in the first three months of life. In this way we can shorten the treatment time considerably and also complete it at a younger age. Finally, early treatment also reduces the risk of the complication of necrosis of the femoral head and significantly decreases the rate of surgical procedures. Only a sufficiently well executed and comprehensively organized sonographic neonatal screening program can produce a definite very early diagnosis and with it almost 100% successful early treatment of all grades of disturbances of hip maturity. Sonographic screening of the newborn is a very important piece in the jigsaw of prophylaxis and primary prevention in our public health care program.

One hundred one clinically normal newborn hips showed varying degrees of sonographic hip dysplasia according to the classification of Graf. None were treated, and after +/- 6 months, radiographs showed that only four had definite dysplasia. Of these, three had had risk factors such as breech delivery or familial predisposition. Forty-three other clinically normal newborn hips showed ultrasonic instability, which spontaneously corrected. The severity of ultrasound dysplasia at birth was not related to ultimate development of the hip. Our results indicate that ultrasound should not be performed as a general screening procedure in clinically normal newborns.

A study was made of 160 long bones taken from 40 native Merino sheep of both sexes. These animals, which represented uniform growth (mean growth-curve values), were divided into four groups which were slaughtered consecutively at 0, 45, 105 and 270 days old (0, 6.4, 15 and 38.5 weeks, respectively). The following bones were studied; humerus, femur, tibia and os coxae. Thin lamellae taken from the metaphyses of the bones obtained were fixed, decalcified and stained with hematoxylin-eosin to assess the development of the various components of growing bony tissue. The bones studied followed the same maturation pattern; the os coxae proved to be the best histological indicator in differentiating the age of the animals studied.

The hip grows by a complex process involving several growth cartilages, each one playing a specific role. Dysfunction of any of these cartilages, whatever its cause, may result in architectural defects of the hip. These defects must be perfectly known in order to foresee the consequences of some hip diseases in children and sometimes to prevent these diseases by orthopaedic measures. The copious blood supply of the acetabulum protects it against all traumas, in contrast with the poor blood supply of the upper end of the femur which exposes to the risk of femoral head necrosis.

As part of a study of the long-term effects of environmental conditions on the health and development of non-human primates, the growth of 60 rhesus monkeys (Macaca mulatta, 34 males and 26 females) was determined longitudinally with biweekly or triweekly measurements of eight body dimensions from one to 54 months of age. Our data showed similar growth to previous studies and provide additional data defining normal rhesus monkey growth under more precisely defined living conditions than were reported in previously published studies on this species.

Of 248 dwarfs with Achondroplasia, Pseudoachondroplastic dysplasia, Metaphyseal chondrodysplasia. Diastrophic dwarfism, Morquio syndrome, and Spondylo-epiphyseal dysplasia Congenita, 85 were managed by orthopedic methods. Experience with bracing is generally unsatisfactory. Surgical lengthening of the lower extremities is not recommended. A number of other surgical procedures are advisable in selected cases.

Biomechanic principles have important implications to film interpretation. Angulation of the femoral neck results in four different types of forces: compression on the medial side, tension on the lateral side, shear stress in the center, and torque forces at the neck-shaft angle. The body's response to these forces results in recognizable trabecular patterns which respond in a predictable manner to disease states. Surgical intervention in the form of hip replacement or fracture fixation must reflect these engineering considerations.