Lower-limb growth: how predictable are predictions?

Surgical Techniques in Primary ACL Reconstruction: Getting It Right the First Time

The ideal anterior cruciate ligament reconstruction (ACLR) is an individualized anatomic approach aimed at restoring the native structure and function of the knee. Surgeons are tasked with difficult decisions during operative planning, including the optimal graft choice for the patient and appropriate anatomic tunnel placement. Special considerations should additionally be given for skeletally immature patients and those at high-risk for failure, including younger, active patients participating in pivoting sports. The purpose of this review is to provide an overview of the individualized approach to ACLR, including the necessary preoperative and operative considerations to optimize patient outcomes.

Prevalence and Predictors of Concomitant Meniscal Surgery During Pediatric and Adolescent ACL Reconstruction: Analysis of 4729 Patients Over 20 Years at a Tertiary-Care Regional Children's Hospital

Background

The rate of concomitant meniscal procedures performed in conjunction with anterior cruciate ligament (ACL) reconstruction is increasing. Few studies have examined these procedures in high-risk pediatric cohorts.

Hypotheses

That (1) the rates of meniscal repair compared with meniscectomy would increase throughout the study period and (2) patient-related factors would be able to predict the type of meniscal operation, which would differ according to age.

Study Design

Cohort study (prevalence); Level of evidence, 2.

Methods

Natural language processing was used to extract clinical variables from notes of patients who underwent ACL reconstruction between 2000 and 2020 at a single institution. Patients were stratified to pediatric (5-13 years) and adolescent (14-19 years) cohorts. Linear regression was used to evaluate changes in the prevalence of concomitant meniscal surgery during the study period. Logistic regression was used to determine predictors of the need for and type of meniscal procedure.

Results

Of 4729 patients (mean age, 16 ± 2 years; 54.7% female) identified, 2458 patients (52%) underwent concomitant meniscal procedures (55% repair rate). The prevalence of lateral meniscal (LM) procedures increased in both pediatric and adolescent cohorts, whereas the prevalence of medial meniscal (MM) repair increased in the adolescent cohort (P = .02). In the adolescent cohort, older age was predictive of concomitant medial meniscectomy (P = .031). In the pediatric cohort, female sex was predictive of concomitant MM surgery and of undergoing lateral meniscectomy versus repair (P≤ .029). Female sex was associated with decreased odds of concomitant LM surgery in both cohorts (P≤ .018). Revision ACLR was predictive of concomitant MM surgery and of meniscectomy (medial and lateral) in the adolescent cohort (P < .001). Higher body mass index was associated with increased odds of undergoing medial meniscectomy versus repair in the pediatric cohort (P = .03).

Conclusion

More than half of the young patients who underwent ACLR had meniscal pathology warranting surgical intervention. The prevalence of MM repair compared with meniscectomy in adolescents increased throughout the study period. Patients who underwent revision ACLR were more likely to undergo concomitant meniscal surgeries, which were more often meniscectomy. Female sex had mixed effects in both the pediatric and adolescent cohorts.

Correlations Between Eight Comprehensive Skeletal Maturity Systems in a Modern Peripubertal Pediatric Population

BACKGROUND

Several skeletal maturity systems allow for accurate skeletal age assessment from a wide variety of joints. However, discrepancies in estimates have been noted when applying systems concurrently. The aims of our study were to (1) compare the agreement among 8 different skeletal maturity systems in modern pediatric patients and (2) compare these discrepancy trends qbetween modern and historic children.

METHODS

We performed a retrospective (January 2000 to May 2022) query of our picture archiving and communication systems and included peripubertal patients who had at least two radiographs of different anatomic regions obtained ≤3 months apart for 8 systems: (1) proximal humerus ossification system (PHOS), (2) olecranon apophysis ossification staging system (OAOSS), (3) lateral elbow system, (4) modified Fels wrist system, (5) Sanders Hand Classification, (6) optimized oxford hip system, (7) modified Fels knee system, and (8) calcaneal apophysis ossification staging system (CAOSS). Any abnormal (ie, evidence of fracture or congenital deformity) or low-quality radiographs were excluded. These were compared with a cohort from a historic longitudinal study. SEM skeletal age, representing the variance of skeletal age estimates, was calculated for each system and used to compare system precision.

RESULTS

A total of 700 radiographs from 350 modern patients and 954 radiographs from 66 historic patients were evaluated. In the modern cohort, the greatest variance was seen in PHOS (SEM: 0.28 y), Sanders Hand (0.26 y), and CAOSS (0.25 y). The modified Fels knee system demonstrated the smallest variance (0.20 y). For historic children, the PHOS, OAOSS, and CAOSS were the least precise (0.20 y for all). All other systems performed similarly in historic children with lower SEMs (range: 0.18 to 0.19 y). The lateral elbow system was more precise than the OAOSS in both cohorts.

CONCLUSIONS

The precision of skeletal maturity systems varies across anatomic regions. Staged, single-parameter systems (eg, PHOS, Sanders Hand, OAOSS, and CAOSS) may correlate less with other systems than those with more parameters.

LEVEL OF EVIDENCE

Level III-retrospective study.

Bone Age Assessment Using Artificial Intelligence in Korean Pediatric Population: A Comparison of Deep-Learning Models Trained With Healthy Chronological and Greulich-Pyle Ages as Labels

OBJECTIVE

To develop a deep-learning-based bone age prediction model optimized for Korean children and adolescents and evaluate its feasibility by comparing it with a Greulich-Pyle-based deep-learning model.

MATERIALS AND METHODS

A convolutional neural network was trained to predict age according to the bone development shown on a hand radiograph (bone age) using 21036 hand radiographs of Korean children and adolescents without known bone development-affecting diseases/conditions obtained between 1998 and 2019 (median age [interquartile range {IQR}], 9 [7-12] years; male:female, 11794:9242) and their chronological ages as labels (Korean model). We constructed 2 separate external datasets consisting of Korean children and adolescents with healthy bone development (Institution 1: n = 343; median age [IQR], 10 [4-15] years; male: female, 183:160; Institution 2: n = 321; median age [IQR], 9 [5-14] years; male: female, 164:157) to test the model performance. The mean absolute error (MAE), root mean square error (RMSE), and proportions of bone age predictions within 6, 12, 18, and 24 months of the reference age (chronological age) were compared between the Korean model and a commercial model (VUNO Med-BoneAge version 1.1; VUNO) trained with Greulich-Pyle-based age as the label (GP-based model).

RESULTS

Compared with the GP-based model, the Korean model showed a lower RMSE (11.2 vs. 13.8 months; P = 0.004) and MAE (8.2 vs. 10.5 months; P = 0.002), a higher proportion of bone age predictions within 18 months of chronological age (88.3% vs. 82.2%; P = 0.031) for Institution 1, and a lower MAE (9.5 vs. 11.0 months; P = 0.022) and higher proportion of bone age predictions within 6 months (44.5% vs. 36.4%; P = 0.044) for Institution 2.

CONCLUSION

The Korean model trained using the chronological ages of Korean children and adolescents without known bone development-affecting diseases/conditions as labels performed better in bone age assessment than the GP-based model in the Korean pediatric population. Further validation is required to confirm its accuracy.

Imaging the pediatric anterior cruciate ligament: not little adults

An increased incidence of anterior cruciate ligament (ACL) injuries in children over the last few decades has led to a corresponding increase in ACL reconstruction procedures in children. In this review, we will illustrate unique features seen when imaging the ACL in children versus adults. After briefly reviewing relevant normal ACL anatomy, we will review imaging findings of congenital ACL dysplasia. This is followed by a discussion of imaging ACL avulsions. Lastly, we will review the different types of ACL reconstruction procedures performed in skeletally immature children and their post-operative appearances.

Growth modulation for angular knee deformities: a practical guideline

PURPOSE OF REVIEW

This study aimed to review the established concepts and advances related to growth modulation for treating knee angular deformities. Although they are considered well tolerated procedures, careful indications and accurate techniques are necessary to ensure good results.

RECENT FINDINGS

In addition to general clinical and radiographic evaluations, new tools such as two-dimensional low-dose radiography and gait analysis have been used to clarify angular and torsional combinations and the impact of mild angulations on the knee joint. Temporary epiphysiodesis is commonly the choice, and it can be performed with different implants such as staples, tension band plates (TBP), percutaneous transphyseal screws (PETS), sutures, and screws.

SUMMARY

Considering its principles, TBP has been preferred for younger children. Cost can be a limitation, and research for alternative implants such as screws and nonabsorbable sutures indicate they might be an alternative in the future. In adolescents, PETS becomes an attractive alternative; however, its reversible character has been controversial, and further studies are needed to establish limits in younger patients.

Intestinal malrotation in a female newborn affected by Osteopathia Striata with Cranial Sclerosis due to a de novo heterozygous nonsense mutation of the AMER1 gene

BACKGROUND

Osteopathia Striata with Cranial Sclerosis (OS-CS), also known as Horan-Beighton Syndrome, is a rare genetic disease; about 90 cases have been reported to date. It is associated with mutations (heterozygous for female subjects and hemizygous for males) of the AMER1 gene, located at Xq11.2, and shows an X-linked pattern of transmission. Typical clinical manifestations include macrocephaly, characteristic facial features (frontal bossing, epicanthal folds, hypertelorism, depressed nasal bridge, orofacial cleft, prominent jaw), hearing loss and developmental delay. Males usually present a more severe phenotype than females and rarely survive. Diagnostic suspicion is based on clinical signs, radiographic findings of cranial and long bones sclerosis and metaphyseal striations, subsequent genetic testing may confirm it.

CASE PRESENTATION

Hereby, we report on a female newborn with frontal and parietal bossing, narrow bitemporal diameter, dysplastic, low-set and posteriorly rotated ears, microretrognathia, cleft palate, and rhizomelic shortening of lower limbs. Postnatally, she manifested feeding intolerance with biliary vomiting and abdominal distension. Therefore, in the suspicion of bowel obstruction, she underwent surgery, which evidenced and corrected an intestinal malrotation. Limbs X-ray and skull computed tomography investigations did not show cranial sclerosis and/or metaphyseal striations. Array-CGH analysis revealed normal findings. Then, a target next generation sequencing (NGS) analysis, including the genes involved in skeletal dysplasias, was performed and revealed a de novo heterozygous nonsense mutation of the AMER1 gene. The patient was discharged at 2 months of age and included in a multidisciplinary follow-up. Aged 9 months, she now shows developmental and growth (except for relative macrocephaly) delay. The surgical correction of cleft palate has been planned.

CONCLUSIONS

Our report shows the uncommon association of intestinal malrotation in a female newborn with OS-CS. It highlights that neonatologists have to consider such a diagnosis, even in absence of cranial sclerosis and long bones striations, as these usually appear over time. Other syndromes with cranial malformations and skeletal dysplasia must be included in the differential diagnosis. The phenotypic spectrum is wide and variable in both genders. Due to variable X-inactivation, females may also show a severe and early-onset clinical picture. Multidisciplinary management and careful, early and long-term follow-up should be offered to these patients, in order to promptly identify any associated morbidities and prevent possible complications or adverse outcomes.

A comparison of osteoarticular allografts and allograft-prosthesis composites for reconstruction of the distal femur after resection of a bone tumour in childhood : a retrospective study

AIMS

Osteoarticular reconstruction of the distal femur in childhood has the advantage of preserving the tibial physis. However, due to the small size of the distal femur, matching the host bone with an osteoarticular allograft is challenging. In this study, we compared the outcomes and complications of a resurfaced allograft-prosthesis composite (rAPC) with those of an osteoarticular allograft to reconstruct the distal femur in children.

METHODS

A retrospective analysis of 33 skeletally immature children with a malignant tumour of the distal femur, who underwent resection and reconstruction with a rAPC (n = 15) or osteoarticular allograft (n = 18), was conducted. The median age of the patients was ten years (interquartile range (IQR) 9 to 11) in the osteoarticular allograft group and nine years (IQR 8 to 10) in the rAPC group (p = 0.781). The median follow-up of the patients was seven years (IQR 4 to 8) in the osteoarticular allograft group and six years (IQR 3 to 7) in the rAPC group (p = 0.483). Limb function was evaluated using the Musculoskeletal Tumor Society (MSTS) score.

RESULTS

At final follow-up, the knee was unstable in 9/18 patients (50%) in the osteoarticular allograft group and 2/15 patients (13%) in the rAPC group (p = 0.026). The median range of motion (ROM) of the knee was 117° (IQR 115° to 120°) in the osteoarticular allograft group and 100° (IQR 95° to 105°) in the rAPC group (p < 0.001). The median MSTS score was 25 (IQR 23 to 26) in the osteoarticular allograft group and 28 (IQR 26 to 29) in the rAPC group (p = 0.007). Osteoarthritic change was detected in 11/18 patients (61%) in the osteoarticular allograft group and in 4/15 (26%) patients in the rAPC group (p = 0.048).

CONCLUSION

In our series, a resurfaced allograft-prosthesis composite provided better knee stability and function, with a lower rate of osteoarthritis; an osteoarticular allograft was associated with better knee ROM.Cite this article: Bone Joint J 2022;104-B(10):1174-1179.

Preliminary results of two novel devices for epiphysiodesis in the reduction of excessive predicted final height in tall stature

BACKGROUND

In the treatment of tall stature, the reduction of excessive predicted final height can either be achieved by hormonal treatment or surgically by temporary (tED) or permanent (pED) epiphysiodesis. The present study evaluates the preliminary results of two novel devices for tED and pED around the knee to reduce the predicted final height.

MATERIALS AND METHODS

A retrospective analysis was performed to evaluate the clinical and radiographic outcome after bilateral epiphysiodesis for the treatment of tall stature. A cohort of 34 patients (16 girls, 18 boys) who underwent either tED or pED between 2015 and 2020 were eligible for analysis based on the electronic patient records and picture archiving and communication system of our orthopaedic teaching hospital. tED was conducted in 11 patients (32%) through bilateral implantation of four RigidTacks™ (Merete, Berlin, Germany) around the knee. Twenty-three patients (68%) received pED, performed with an EpiStop™ trephine (Eberle, Wurmberg, Germany). The mean overall follow-up time was 2.9 years.

RESULTS

The mean age at surgery was 12.3 years in girls and 13.2 years in boys. Patients had a mean body height of 175.2 cm in girls and 184.7 cm in boys at surgery. The mean predicted final height was 191.4 cm in girls and 210.4 cm in boys. At the last follow-up, 26 patients (76.5%) had achieved skeletal maturity. The mean height of skeletally mature patients was 187.2 cm in girls and 198.5 cm in boys. A mean reduction of the predicted final height of 5.9 cm in girls and 8.7 cm in boys was achieved, corresponding to a reduction in remaining growth of 46% in girls and 38% in boys. Secondary frontal plane deformities of the knee were detected in 5/11 patients (45.5%) in the tED group and 1/23 treatments (4.3%) in the pED group.

CONCLUSIONS

tED and pED have both proven to be efficient at achieving growth inhibition to reduce excessive predicted height. However, tED has been associated with an increased risk of secondary angular deformities of the knee. Furthermore, the risk of implant-related complications and the necessity of a subsequent surgical intervention for implant removal have led our study group to abandon tED when treating tall stature. Long-term results of both procedures are pending.

LEVEL OF EVIDENCE: 4

Risk of reoperation after primary anterior cruciate ligament reconstruction in children and adolescents

OBJECTIVE

To examine the incidence and risk factors of any-cause reoperation after primary ACLR in children and adolescents.

DESIGN

Retrospective Cohort.

SETTING

Electronic medical records from a large tertiary care, single institution integrated healthcare delivery system.

PATIENTS

Patients were under the age of 18 years and had anterior cruciate ligament reconstruction. They were excluded if they had a multi-ligamentous knee injury or <1 year follow-up.

INTERVENTIONS

Patients were further identified to have undergone a subsequent knee operation ipsilaterally or contralateral ACLR.

MAIN OUTCOME MEASURES

The rate of any-cause reoperation was our primary outcome measure.

RESULTS

The median age was 16. There were 208 females (53.9%) and 178 males (46.1%) included. The median follow-up was 25 months with a minimum of 12 months (interquartile range: 16.0, 46.0). The rate of any-cause reoperation was 34.7%. There was no statistically significant difference between those who underwent reoperation versus those who did not undergo reoperation relative to age, sex, BMI, graft type, or the presence of concomitant meniscal injury. The rates of ipsilateral ACLR and contralateral ACLR at any time during the study period was 8.0% and 10.9% respectively. There was no statistically significant difference for rate of reoperation between graft types, between various concomitant injuries, between those who underwent meniscus repair or no repair.

CONCLUSIONS

This study reflects a 34.7% rate of a subsequent knee operation after ACLR in patients younger than 18 years. These findings can be used to inform pediatric patients undergoing primary ACLR on their risk of returning to the operating room.

Re-Assessment of Applicability of Greulich and Pyle-Based Bone Age to Korean Children Using Manual and Deep Learning-Based Automated Method

PURPOSE

To evaluate the applicability of Greulich-Pyle (GP) standards to bone age (BA) assessment in healthy Korean children using manual and deep learning-based methods.

MATERIALS AND METHODS

We collected 485 hand radiographs of healthy children aged 2-17 years (262 boys) between 2008 and 2017. Based on GP method, BA was assessed manually by two radiologists and automatically by two deep learning-based BA assessment (DLBAA), which estimated GP-assigned (original model) and optimal (modified model) BAs. Estimated BA was compared to chronological age (CA) using intraclass correlation (ICC), Bland-Altman analysis, linear regression, mean absolute error, and root mean square error. The proportion of children showing a difference >12 months between the estimated BA and CA was calculated.

RESULTS

CA and all estimated BA showed excellent agreement (ICC ≥0.978, p<0.001) and significant positive linear correlations (R²≥0.935, p<0.001). The estimated BA of all methods showed systematic bias and tended to be lower than CA in younger patients, and higher than CA in older patients (regression slopes ≤-0.11, p<0.001). The mean absolute error of radiologist 1, radiologist 2, original, and modified DLBAA models were 13.09, 13.12, 11.52, and 11.31 months, respectively. The difference between estimated BA and CA was >12 months in 44.3%, 44.5%, 39.2%, and 36.1% for radiologist 1, radiologist 2, original, and modified DLBAA models, respectively.

CONCLUSION

Contemporary healthy Korean children showed different rates of skeletal development than GP standard-BA, and systemic bias should be considered when determining children's skeletal maturation.

Influence of Sport Practice and Body Weight on Physical Fitness in Schoolchildren Living in the Campania Region

Background: Physical fitness (PF) levels correlate with health hallmarks at all ages. In this study, w aimed to determine the PF level of schoolchildren from the Campania Region (Italy) through health-related PF (HRPF) components, taking into account body weight and sport practice (SP). Methods: PF level was determined in 565 schoolchildren aged 10−13 (11.7 ± 1.0 yrs; m: 353, f: 212) using some of the Eurofit battery tests. Results: 77% children practiced sport, boys more than girls (86% vs. 63%, respectively; p < 0.05). Boys performed better than girls (p < 0.05) in the Plate Tapping, Standing Broad Jump, Bent-Arm Hang, and 10 × 5 m Shuttle Run tests; girls performed better in the Sit-and-Reach Test (p < 0.05). Conclusion: Overweight/obese status negatively affects the muscular strength of lower limbs, even if it progressively improves during growth. SP was revealed to be a determinant in performance only in some PF tests, likely due to the heterogeneous training level among boys and girls who practice sport.

The Effect of Three-Year Swim Training on Cardio-Respiratory Fitness and Selected Somatic Features of Prepubertal Boys

The data regarding somatic and physiological effects of sport-related physical activities in youth are limited. Moreover, whether exercise training is capable of increasing cardio-respiratory fitness remains a disputable issue. The study undertook to assess the effect of swimming training on cardio-respiratory fitness (CRF) and the development of physical traits in prepubertal boys, and to determine which of the traits is the best predictor of their CRF. Forty 10-year old prepubertal boys (10.5 ± 0.3 y) were divided into two groups (swimmers (SG), n = 20, and controls (CG), n = 20), which underwent anthropometric measurements and performed a 20 m shuttle run test (20 mSRT) semi-annually over a 3-year period. CRF indices (the number of 20 mSRT shuttles, maximal speed, and VO2max) were higher overall in the SG compared with the CG (p < 0.001). The values of the main physique variables increased faster in the CG, but the groups showed no differentiation of physical traits. In both groups, CRF indices were associated with the participants’ physical traits, the most strongly with the sum of four skinfold thicknesses in the SG and knee breadth in the CG. These results suggest that swimming training is a form of additional physical activity that improves prepubertal boys’ CRF but does not significantly affect their physical development. In using the 20 mSRT to assess the CRF of prepubertal boys, their physical activity level and age-related changes in body fatness need to be considered.

Rapid Spike in Hip Adduction Strength in Early Adolescent Footballers: A Study of 125 Elite Male Players From Youth to Senior

PURPOSE

To investigate the differences in hip adductor and abductor muscle strength in elite male footballers from youth to senior level.

METHODS

We tested 125 players from the under-13-years (U'13) to senior squads of a Danish male professional football club in this cross-sectional design study. Hip adductor and abductor force (in newtons), torque (in newton meters), normalized torque (in newton meters per body mass), and adduction-to-abduction ratio were measured using handheld dynamometry.

RESULTS

Between U'13 and senior level, adductor force increased by 104%, torque by 127%, and normalized torque by 21%. Abductor force increased by 78%, torque by 126%, and normalized torque by 17%. For incremental differences between age groups, significant increases were observed between the ages of U'13 to U'14 (18%-39%) and U'14 to U'15 (19%-33%) for all strength measures (P ≤ .021). No incremental difference was observed for adductor-to-abductor ratio.

CONCLUSIONS

The large increases in hip adductor and abductor strength occurring between the ages of U'13 and U'15 offer insight into the strength capabilities and stress demands in these players, which may relate to injury vulnerability, and facilitate clinicians in selecting best-suited exercise interventions.

Anterior Cruciate Ligament Rupture in Skeletally Immature Patients

In the past 20 years, sports injuries in pediatric and adolescent athletes have increased dramatically, with anterior cruciate ligament (ACL) injuries accounting for more than 25% of all knee injuries at this age. Diagnosis is based on detailed clinical history, physical examination, and imaging assessment, where magnetic resonance imaging plays a central role. The growing immature skeleton presents specific characteristics, which require unique methods for surgical reconstruction, ideally avoiding the physes or minimizing the risk of damaging them. Specific rehabilitation protocols are needed, and these patients face a higher risk of recurrent and contralateral ACL injury. Nonsurgical treatment or delayed reconstruction has been associated with persistent instability, activity modifications, worst functional outcomes, and increased risk of irreparable injuries to menisci and articular cartilage. Consequently, surgical stabilization is the preferred treatment for most patients, despite the eventual risk of angular deformities or limb-length discrepancies due to iatrogenic physeal injury. A variety of surgical techniques have been described, depending on the skeletal maturity and growth remaining. Targeted prevention programs play a key role in reducing the risk of ACL injury, are easy to implement, and require no additional equipment. High-quality evidence supports its use in all pediatric athletes.

Dimensions of the anterior cruciate ligament and thickness of the distal femoral growth plate in children: a MRI-based study

BACKGROUND

When determining the dimensions of an anterior cruciate ligament (ACL) graft in children, bone age should be considered in addition to the patient's age, gender, and body height.

OBJECTIVES

We aimed to determine the relationship between age, gender, and ACL dimensions as well as thickness of growth plate cartilage of the distal femur during puberty.

METHODS

We retrospectively analyzed MRI scans of the knee in 131 children (82 girls, 49 boys) aged 6-18 years (mean age: 14.9 ± 2.6 years). ACL length and width as well as thickness of the growth plate cartilage at the distal femoral epiphysis were measured.

RESULTS

Mean ACL length increased linearly up to the age of 12 years in females and 14 years in males; thereafter, mean ACL length remained constant. Mean ACL length was largest at the age of 12 to < 13 years (38.18 mm) in females and at 15 to < 16 years (39.38 mm) in males. Mean ACL width increased up to the age of 12 years in girls and 13 years in boys. After the age of 12 years, both the ACL length and width were significantly larger in boys than girls (p = 0.002 and p = 0.045, respectively). Mean thickness of the growth plate cartilage of the distal femur remained stable up to the age of 12 years in girls and 14 years in boys. Thickness of the growth plate cartilage changed most markedly between the age intervals of 11 to < 12 years and 12 to < 13 years in girls and between the age intervals of 13 to < 14 years and 14 to < 15 years in boys.

CONCLUSIONS

ACL dimensions depended on both age and gender during the growth period. Measurement of cartilage thickness of the femoral distal growth plate proved to be an objective parameter to assess the maturation stage of local bone. This may be useful for the planning and timing of orthopedic ACL procedures.

LEVEL OF EVIDENCE

III-retrospective cohort study.

[Epiphysiodesis and hemiepiphysiodesis : Physeal arrest and guided growth for the lower extremity]

The principals of growth arrest by epiphysiodesis and growth guidance by hemiepiphysiodesis are effective and powerful surgical techniques in pediatric orthopedics. These procedures can be used to correct leg length discrepancies as well as sagittal, coronal and oblique deformities. A differentiation is made between temporary and permanent techniques. The most significant advantage is that these techniques are minimally invasive and have low complication rates compared to acute osteotomy and gradual deformity correction. For optimal outcome an exact preoperative planning is needed to ensure accurate timing of the procedure, especially when permanent epiphysiodesis techniques are used. Although epiphysiodesis and hemiepiphysiodesis around the pediatric knee are most frequently used and can be considered the gold standard treatment of coronal plane deformities and leg length discrepancies, novel techniques for the hip and ankle are increasingly being performed. The successful clinical results with low complications support the broad use of hemiepiphysiodesis and epiphysiodesis for a variety of indications in the growing skeleton with deformities and leg length differences.

Differences in skeletal growth pattern of yoga practising adolescent girls: A cross-sectional study

Background

Yogasana improves both mental and physical health. There is sparse systematic research on the growth of yogasana practising adolescents.

Objectives

This study aims to assess the differential skeletal growth pattern among pre-adolescent and adolescent girls as a result of yoga practice.

Methods

A cross-sectional anthropometric study was conducted on stature (height), sitting height and leg length of 757 school-going girls (4-15 years old), divided in two groups, Yoga Group (YG) (n=380) and age matched Control Group (CG) (n=377) participants participating in recreational games other than yoga. Descriptive and inferential statistical analyses were applied. Unpaired t-test was performed for assessment of level of significance and Pearson's correlation (r) test was performed to to identify the association between growth pattern of stature and leg length at specific ages.

Results

The physical growth showed an ascending trend in both Yoga group (YG)2 participants and control group (CG)3 . At the onset of adolescence (10–12 years) the mean stature and leg length of YG participants were retarded (p < 0.05). Sitting height in YG was significantly (p < 0.05) low only in 10-year-olds. The similar trends were observed in stature and leg length in YG participants at 10 years (5th and 10th percentile) and 12 years (90th and 95th percentile). There was strong positive relationship between stature and leg length of YG participants (10 years, r = 0.86, p < 0.01; 11 years, r = 0.86, p < 0.01; 12 years, r = 0.72, p < 0.01). The stunted growth in YG participants during adolescence may be related to retarded growth of leg length.

Conclusions

Intense yogasana practice with greater skeletal stress possibly hinders stature in adolescent girls from 10 to 12 years. This may compromise with the natural growth pattern, necessitating special care during yoga training among adolescents while selecting the type, intensity and duration of yogasanas practice.

Difference between bone age at the hand and elbow at the onset of puberty

In the pubertal period, bone age advances rapidly in conjunction with growth spurts. Precise bone-age assessments in this period are important, but results from the hand and elbow can be different. We aimed to compare the bone age between the hand and elbow around puberty onset and to elucidate the chronological age confirming puberty onset according to elbow-based bone age.A total of 211 peripubertal subjects (127 boys and 84 girls) who underwent hand and elbow radiographs within 2 months was enrolled. Two radiologists and a pediatric orthopedic surgeon assessed bone age. Hand bone age was graded using the Greulich-Pyle (GP) method, and elbow bone age was determined using the Sauvegrain method. The correlation of 2 methods was evaluated by Demining regression analysis, and the mean absolute difference (MAD) with chronological age was compared between pre-pubertal and pubertal subjects. Receiver-operating characteristic curve analysis was performed to determine the chronological age confirming puberty onset.There was a statistically significant difference in bone age revealed by the GP and Sauvegrain methods in the pubertal group. In the pubertal group, the MAD was 1.26 ± 0.90 years with the GP method and 0.61 ± 0.47 years with the Sauvegrain method in boys (P < .001), while in girls, the MAD was 0.84 ± 0.60 years and 0.53 ± 0.36 years with the same 2 methods (P = .033). The chronological age for confirming puberty onset using the elbow was 12.2 years in boys and 10.3 years in girls.The bone ages of hand and elbow were different at puberty, and the elbow was a more reliable location for bone-age assessment at puberty. Puberty onset according to elbow occurred slightly earlier than expected.

Characteristics of inhomogeneous lower extremity growth and development in early childhood: a cross-sectional study

BACKGROUND

Early childhood is a transferring stage between the two accelerated growth periods (infant and adolescent). Body dimensions are related to physical growth and development. The purpose of this study was to investigate physical growth in terms of anthropometry, muscle growth of the lower extremity, and functional development over early childhood.

METHODS

A cross-sectional study was carried out on 29 preschool children (PS: 3-5 years), 21 school children (SC: 6-8 years), and 22 adults (AD: 20-35 years). Lower extremity characteristics (segmental dimensions, muscle and adipose tissue thicknesses of the thigh and lower leg), and voluntary joint torque (knee and ankle) were measured. Correlations between parameters and group comparisons were performed.

RESULTS

All the parameters except for body mass index (BMI) and subcutaneous adipose tissue thickness were correlated with age for PS and SC combined (r = 0.479-0.920, p < 0.01). Relative thigh and shank lengths to body height were greatest in AD and smallest in PS (p < 0.05) but the relative foot dimensions were significantly larger in PS and SC than in AD (p < 0.05). Relative subcutaneous adipose tissue thickness was largest in PS and lowest in AD. Muscle thickness and the muscle volume measure (estimated from muscle thickness and limb length) were significantly larger in older age groups (p < 0.05). All groups showed comparable muscle thickness when normalized to limb length. Joint torque normalized to estimated muscle volume was greatest for AD, followed by SC and PS (p < 0.05).

CONCLUSIONS

Relative lower extremity lengths increase with age, except for the foot dimensions. Muscle size increases with age in proportion to the limb length, while relative adiposity decreases. Torque-producing capacity is highly variable in children and rapidly develops toward adulthood. This cross-sectional study suggests that children are not a small scale version of adults, neither morphologically nor functionally.

Analysis of Association between Morphometric Parameters of Growth Plate and Bone Growth of Tibia in Mice and Humans

OBJECTIVE

The purposes of this study are to evaluate which growth plate parameters are associated with bone growth in mice and to compare the mouse results with those in humans.

DESIGN

The sagittal sections of the proximal growth plate of the mouse tibia from neonate to young adult stages were subjected to histomorphometric and functional analyses. The radiographic images of tibias of human patients until puberty were analyzed to obtain the tibia length and the proximal growth plate height. It was found that a linear correlation best modeled the relationship between the growth plate variables with the tibia growth rate and length.

RESULTS

In mice, total height, resting zone height, combined height of the proliferation and prehypertrophic zones, proliferation activity, and the total width of tibia growth plate showed high linear correlation with tibia bone length and bone growth rate, but the hypertrophic zone height and the growth plate area did not. In both mice and humans, the total growth plate width of tibia was found to have the strongest correlation with tibia length and growth rate.

CONCLUSIONS

The results validated that growth plate total height, the height of the resting zone and cell proliferation activity are appropriate parameters to evaluate the balance between growth plate activity and bone growth in mice, consistent with previous reports. The study also provided a new growth plate parameter candidate, growth plate width for growth plate activity evaluation in both mouse and human tibia bone.

Lower-Extremity Segment-Length Prediction Accuracy of the Sanders Multiplier, Paley Multiplier, and White-Menelaus Formula

BACKGROUND

Several methods are available to estimate leg lengths at maturity to facilitate the determination of timing of epiphysiodesis. We compared the Paley multiplier, Sanders multiplier, and White-Menelaus methods in an epiphysiodesis-aged cohort. We assessed intra- and interrater reliability for Sanders skeletal stages and Greulich and Pyle atlas skeletal age.

METHODS

Actual growth was recorded in healthy, unoperated femoral and tibial segments from an epiphysiodesis database. The predicted and actual lengths were compared with use of the Paley multiplier and White-Menelaus methods, Greulich and Pyle skeletal age, and the Sanders multiplier using Sanders stages. Intra- and interrater reliability were assessed in a separate group of 76 skeletal age films.

RESULTS

The cohort included 148 femora and 195 tibiae in 197 patients. Femoral length at maturity was slightly underestimated by the Sanders multiplier and staging, was overestimated by the Paley multiplier and skeletal age, and was most accurately predicted with use of the White-Menelaus formula and skeletal age. All methods overestimated tibial length at maturity. The whole-leg prediction accuracy of the Sanders multiplier and White-Menelaus formula were comparable and were more accurate than that of the Paley multiplier. For Sanders skeletal staging, the interrater reliability varied from 0.86 to 0.88 and the intrarater reliability varied from 0.87 to 0.96. For Greulich and Pyle skeletal age, the interrater reliability varied from 0.87 to 0.89 and the intrarater reliability varied from 0.91 to 0.95.

CONCLUSIONS

Use of the Sanders multiplier and skeletal stages was more accurate than the Paley multiplier and skeletal age in this cohort. Use of the White-Menelaus formula and skeletal age was slightly more accurate in predicting femoral length and slightly less accurate in predicting tibial length compared with the Sanders multiplier. Intra- and interrater reliability were similar between Sanders skeletal stages and Greulich and Pyle atlas skeletal age. The White-Menelaus formula and skeletal age was the recommended method for predicting lower-extremity segment lengths at maturity and epiphysiodesis effect. Although easier to recall without referencing an atlas and not sex-specific, Sanders skeletal staging does not correspond directly to years of growth remaining, and thus cannot be used with the White-Menelaus formula.

CLINICAL RELEVANCE

The Greulich and Pyle atlas to determine skeletal age and the White-Menelaus formula to determine growth remaining are reliable predictors of epiphysiodesis effect in the lower extremities.

Association between ocular axial length and anthropometrics of Asian adults

Objective

The purpose of this study is to analyze axial length, body height, hand length, and foot length to find new factors that predict myopia and to identify gender differences as one of the factors of high myopia. A cross-sectional study was conducted as a single observation. Body height, hand length, and foot length were measured according to standard anthropometric methods. Axial length, retinal thickness, and choroidal thickness were measured using the IOL Master 700 and the Heidelberg Spectralis-OCT. To account for body height differences among participants, foot length/body height and hand length/body height were analyzed using a mixed-effects model.

Results

A total of 80 eyes (men, n = 20, 40 eyes; women, n = 20, 40 eyes) were analyzed. The mean age was 33.5 years (range 21–59 years, SD: 9.6). For choroidal thickness, there was a significant association with axial length in men (p < 0.001) and a trend toward an association in women (p = 0.072). There was also a significant association between foot length/body height and axial length in men (p = 0.015), but not in women (p = 0.58). These results suggest that factors that determine body height and foot length may be related to axial length, although they vary by gender.

Return to Sport After Bone-Patellar Tendon-Bone Autograft ACL Reconstruction in High School-Aged Athletes

Background:

Anterior cruciate ligament (ACL) injuries are occurring with increasing frequency in the adolescent population. Outcomes after ACL reconstruction (ACLR) are inconsistently reported in homogeneous patient populations.

Purpose/Hypothesis:

To evaluate outcomes after bone–patellar tendon–bone (BTB) autograft ACLR in competitive high school–aged athletes by examining return to sport (RTS), patient satisfaction, and reinjury rates. Our hypothesis was that RTS rates and satisfaction will be high and reinjury rates will be low.

Study Design:

Case series; Level of evidence, 4.

Methods:

An institutional ACL registry was utilized to identify competitive high school–aged athletes (14-18 years old) who underwent primary ACLR using BTB autograft with a minimum 2-year follow-up. A postoperative questionnaire was administered to determine rates and types of RTS, quality of sports performance, reinjury, and satisfaction. Uni- and multivariable analyses were used to identify demographic, sport-specific, and clinical factors related to RTS.

Results:

A total of 53 patients were included (mean ± SD age at the time of surgery, 16.6 ± 1.34 years). Mean follow-up was 3.78 ± 0.70 years (range, 2.60-4.94 years). The overall ipsilateral ACL retear rate was 7.5% (n = 4). There were 10 subsequent ACL tears to the contralateral knee (19%). Forty-four (83%) patients successfully returned to at least their prior level of sport at a mean 10.5 ± 8.7 months (range, 3-48 months). Overall satisfaction was high, with 91% of patients very satisfied with the outcome. Higher confidence levels regarding performance of the reconstructed knee were associated with increased probability of RTS on multivariate analysis.

Conclusion:

BTB autograft ACLR results in high rates of RTS and satisfaction and low rates of subsequent ipsilateral ACL injuries in competitive high school–aged athletes. Patients with higher confidence in performance of the reconstructed knee are more likely to return to at least their prior level of sport.

Assessment of rapidly advancing bone age during puberty on elbow radiographs using a deep neural network model

OBJECTIVES

Bone age is considered an indicator for the diagnosis of precocious or delayed puberty and a predictor of adult height. We aimed to evaluate the performance of a deep neural network model in assessing rapidly advancing bone age during puberty using elbow radiographs.

METHODS

In all, 4437 anteroposterior and lateral pairs of elbow radiographs were obtained from pubertal individuals from two institutions to implement and validate a deep neural network model. The reference standard bone age was established by five trained researchers using the Sauvegrain method, a scoring system based on the shapes of the lateral condyle, trochlea, olecranon apophysis, and proximal radial epiphysis. A test set (n = 141) was obtained from an external institution. The differences between the assessment of the model and that of reviewers were compared.

RESULTS

The mean absolute difference (MAD) in bone age estimation between the model and reviewers was 0.15 years on internal validation. In the test set, the MAD between the model and the five experts ranged from 0.19 to 0.30 years. Compared with the reference standard, the MAD was 0.22 years. Interobserver agreement was excellent among reviewers (ICC: 0.99) and between the model and the reviewers (ICC: 0.98). In the subpart analysis, the olecranon apophysis exhibited the highest accuracy (74.5%), followed by the trochlea (73.7%), lateral condyle (73.7%), and radial epiphysis (63.1%).

CONCLUSIONS

Assessment of rapidly advancing bone age during puberty on elbow radiographs using our deep neural network model was similar to that of experts.

KEY POINTS

• Bone age during puberty is particularly important for patients with scoliosis or limb-length discrepancy to determine the phase of the disease, which influences the timing and method of surgery. • The commonly used hand radiographs-based methods have limitations in assessing bone age during puberty due to the less prominent morphological changes of the hand and wrist bones in this period. • A deep neural network model trained with elbow radiographs exhibited similar performance to human experts on estimating rapidly advancing bone age during puberty.

Applicability of Magnetic Resonance Imaging of the Knee in Forensic Age Estimation

ABSTRACT

Age estimation in forensic medicine practice is of particular importance to the legal systems, and it is one of the current research topics in forensic medicine. Age determination is most frequently performed by radiological methods, but recently, nonionized methods are preferred for nonmedical indications. Therefore, we aimed to examine feasibility of MRI imaging, which provides nonionized, noninvasive, and detailed images, in forensic age estimation and to expand the database on this subject. The MRI images of the patients between the ages of 10 and 25 years, who visited Cukurova University Faculty of Medicine between January 2012 and April 2018 for any reason, were retrospectively analyzed according to the staging method described by Dedouit et al. The stage 5 ossification in distal femoral epiphysis indicated an age over 18 years in both sexes (except for 2 cases of 14 and 15 years). The stage 5 ossification in proximal tibial epiphysis indicated an age older than 18 years (except for 1 male case at the age of 15 years and 2 female cases at the age of 14 and 17 years, respectively). It was determined that stage 1 and stage 2 in both distal femur and proximal tibial epiphysis were last seen in younger than 18 years in both sexes. Our study data show that MRI imaging is a nonionized method that can be used in addition to other radiological methods in determining the age limit of 18 years.

Epiphysiodesis for the treatment of tall stature and leg length discrepancy

Painful orthopedic conditions associated with extreme tall stature and leg length discrepancy (LLD) include back pain and adopting bad posture. After failure of conservative treatment options, blocking of the growth plates (epiphysiodesis) around the knee emerged as gold standard in patients with tall stature and LLD in the growing skeleton. Surgical planning includes growth prediction and evaluation of bone age. Since growth prediction is associated with a certain potential error, adequate planning and timing of epiphysiodesis are the key for success of the treatment. LLD corrections up to 5 cm can be achieved, and predicted extreme tall stature can be limited. Percutaneous epiphysiodesis techniques are minimally invasive, safe and efficient methods with low complication rates. In general, a multidisciplinary approach should be pursued when treating children and adolescents with tall stature.

The Actions of IGF-1 in the Growth Plate and Its Role in Postnatal Bone Elongation

PURPOSE OF REVIEW

Bone elongation is a complex process driven by multiple intrinsic (hormones, growth factors) and extrinsic (nutrition, environment) variables. Bones grow in length by endochondral ossification in cartilaginous growth plates at ends of developing long bones. This review provides an updated overview of the important factors that influence this process.

RECENT FINDINGS

Insulin-like growth factor-1 (IGF-1) is the major hormone required for growth and a drug for treating pediatric skeletal disorders. Temperature is an underrecognized environmental variable that also impacts linear growth. This paper reviews the current state of knowledge regarding the interaction of IGF-1 and environmental factors on bone elongation. Understanding how internal and external variables regulate bone lengthening is essential for developing and improving treatments for an array of bone elongation disorders. Future studies may benefit from understanding how these unique relationships could offer realistic new approaches for increasing bone length in different growth-limiting conditions.

Pediatric Anterior Cruciate Ligament Reconstruction

The increasing incidence of anterior cruciate ligament injuries in skeletally immature children demands careful attention by orthopedic surgeons. Assessing skeletal age is essential to selecting the appropriate reconstruction technique. Males with a bone age of 15 years or older and females of 13 years and older are ideal candidates for a transphyseal anterior cruciate ligament reconstruction because there is minimal risk of growth disturbance. Children with substantial growth remaining (skeletal age males ≤12 years and females ≤10 years) seem to be at risk for more significant growth disturbance, so we generally recommend physeal-sparing techniques for these younger patients.

Reference ranges for knee height in Argentine children and adolescents aged 2 to 18 years

OBJECTIVES

Measurement of height is essential in the anthropometric assessment of growth and nutritional status. In some conditions, height measurement may be difficult or impossible. Proxy measurement such as knee height (KH) have been proposed to predict stature in such cases, but reference percentile ranges and charts for healthy, well-nourished children are currently unavailable. This study was designed to develop sex-specific KH reference percentile ranges and charts in Argentine children ranging from 2 to 18 years of age.

METHODS

We collected and analyzed cross-sectional data for KH from 861 Argentine children and adolescents aged 2 to 18 years. Generalized additive models for location, scale, and shape were used to calculate semiparametric smoothed percentile reference ranges, and charts by age and sex. Linear regression and correlation analyses were performed to know the association between KH and height.

RESULTS

The new reference ranges show that KH growth rose sharply until puberty. Peak KH velocity occurs 1 year earlier than peak height velocity. At puberty KH growth decelerated rapidly in females and increased slightly until 15 years and plateaued at this age, while it had a more gradual deceleration in males up to 11 years old, later increased slightly until 17 years and plateaued at this age. The correlation coefficient between height and KH was r = 0.98 for both sexes (p < .001).

CONCLUSIONS

The new reference percentile ranges for KH measures for healthy children and adolescents provide a useful growth and nutritional assessment tool in a wide variety of settings. KH has a strong agreement with stature.

Is Anteromedial Drilling Safe in Transphyseal Anterior Cruciate Ligament Reconstruction in Adolescents with Growth Remaining?

BACKGROUND

Previous reports of transphyseal drilling in anterior cruciate ligament (ACL) reconstruction have demonstrated good clinical outcomes without subjective changes in further skeletal development. The purpose of this study is to evaluate radiographic changes during continued growth following a transphyseal ACL reconstruction using an anteromedial femoral (AM) drilling technique in patients with >18 months of growth remaining.

METHODS

A review of consecutive adolescents who underwent a soft tissue transphyseal ACL reconstruction using an AM drilling technique was performed. Inclusion criteria was 18 months of growth remaining based on radiographic bone age and standing radiographs at least one year from the index procedure. Demographic, preoperative, and postoperative data, and follow-up three-foot standing lower extremity radiographs were reviewed. Radiographic data included femoral length, tibial length, total lower extremity length, mechanical axis deviation (MAD), lateral distal femoral angle (LDFA), and medial proximal tibial angle (MPTA).

RESULTS

In total 12 adolescent patients with a mean age of 13.4 years (range, 12.3 to 14.4) and bone age of 13.4 years (11.5 to 14) at the time of surgery were included. At an average of 2.27-year follow-up (412 to 1058 d), there was no difference in the total growth of the operative and nonoperative limb (48.5 mm vs. 47 mm; P=0.36). In addition, the average increases in femoral length (23.4 mm) and tibial length (25.8 mm) were not statistically different between the operative and the nonoperative limb (P=0.12; P=0.75). There was no statistical difference in mechanical axis deviation, LDFA, or MPTA between preoperative and postoperative radiographs. Mean differences in operative and nonoperative coronal angular changes were all <1.5 degrees.

CONCLUSIONS

With at least 2 years of growth remaining, transphyseal ACL reconstruction with anteromedial drilling did not significantly affect the physis or residual growth compared with the contralateral extremity. Although this technique may create a larger defect in the physis, standing radiographs demonstrate there is no change in limb length or angulation in growing adolescents approximately 2 years after surgery.

LEVEL OF EVIDENCE

This is a case series; Level IV evidence.

[Application of proximal tibial hemiprosthesis replacement and second-stage revision for proximal tibial osteosarcoma in three children]

Objective

To investigate the feasibility and effectiveness of proximal tibial hemiprosthesis replacement in the first stage and prosthesis revision in the second stage in reducing the risk of length discrepancy of limbs in children with proximal tibial osteosarcoma.

Methods

Between 2009 and 2013, 3 children with conventional osteosarcoma at the proximal tibia (stage ⅡB) were treated. There were 2 boys and 1 girl. They were 12, 13, and 13 years old, respectively. After 4 courses of preoperative chemotherapy, the proximal tumor segmental resection and proximal tibial hemiprosthesis replacement were performed. Then the patients underwent prosthetic revision in the second stage when they were 20, 17, and 17 years old, respectively.

Results

All patients successfully completed two stages of operations. The length discrepancy of lower limb after the second stage operation were 19, 7, and 21 mm, respectively. Three patients were followed up 13, 3, and 27 months after the second stage operation, and the lower extremities functions were satisfactory. The Musculoskeletal Tumor Society (MSTS) score was 26, 27, and 25, respectively.

Conclusion

The proximal tibial hemiprosthesis replacement in the first stage combined with prosthesis revision in the second stage for treating the proximal tibia osteosarcoma in children can keep the distal femur growth ability, reduce the length discreapancy of lower limb, and obtain satisfactory stability and good function.

The impact of bipedal mechanical loading history on longitudinal long bone growth

Longitudinal bone growth is accomplished through a process where proliferating chondrocytes produce cartilage in the growth plate, which ultimately ossifies. Environmental influences, like mechanical loading, can moderate the growth of this cartilage, which can alter bone length. However, little is known about how specific behaviors like bipedalism, which is characterized by a shift in body mass (mechanical load), to the lower limbs, may impact bone growth. This study uses an experimental approach to induce bipedal behaviors in a rodent model (Rattus norvegicus) over a 12-week period using a treadmill-mounted harness system to test how rat hindlimbs respond to the following loading conditions: 1) fully loaded bipedal walking, 2) partially loaded bipedal walking, 3) standing, 4) quadrupedal walking, and 5) no exercise control. These experimental conditions test whether mechanical loading from 1) locomotor or postural behaviors, and 2) a change in the magnitude of load can moderate longitudinal bone growth in the femur and tibia, relative to controls. The results demonstrate that fully loaded bipedal walking and bipedal standing groups showed significant differences in the percentage change in length for the tibia and femur. When comparing the change from baseline, which control for body mass, all bipedal groups showed significant differences in tibia length compared to control groups. However, there were no absolute differences in bone length, which suggests that mechanical loads from bipedal behaviors may instead be moderating changes in growth velocity. Implications for the relationship between bipedal behaviors and longitudinal bone growth are discussed.

Outcomes and subjective assessment of rotation-plasty in patients with proximal femoral focal deficiency

This study presents outcomes of rotation-plasty for unilateral proximal femoral focal deficiency in the adolescent population. The function, timing of knee fusion, and complications were presented as well as patients' assessment of their function and appearance. Eight patients, aged 8.37 years (range: 3-16 years) during surgery, were evaluated. The mean follow-up duration was 9.25 years (range: 6-12 years). At follow-up, all the patients were pain free and able to ambulate outdoors. Complications included derotation of the foot in five patients, necessitating a re-rotation osteotomy in two. All patients accepted their appearance, considering the rotation-plasty beneficial for their functional status.

Constant inhibition in congenital lower extremity shortening: does it begin in utero?

BACKGROUND

Limb-length discrepancy (LLD) in children with congenital lower extremity shortening is constant in proportion from birth to skeletal maturity (known as constant inhibition), but its developmental pattern in utero is unknown. The popular prenatal multiplier method to predict LLD at birth assumes constant inhibition in utero to be true. Verifying the in utero developmental pattern of LLD, and thus confirming the validity of the prenatal multiplier method, is crucial for meaningful prenatal parental counseling.

OBJECTIVE

To elucidate the in utero developmental pattern of LLD in fetuses with congenital lower extremity shortening.

MATERIALS AND METHODS

Clinical indications for 3,605 lower extremity radiographs performed on infants (<1 year old) at a large tertiary hospital over a 17-year period were reviewed. Inclusion criteria were (1) diagnosis of congenital lower extremity shortening, (2) bilateral lower limb postnatal radiographs documenting LLD and (3) fetal ultrasound (US) documenting LLD. Available measurements of femoral, tibial and fibular lengths on fetal US and postnatal radiographs were collected. Prenatal and postnatal length ratios of shorter-to-longer bones were calculated and compared.

RESULTS

Eighteen infants met inclusion criteria. Diagnoses were proximal focal femoral deficiency=4, congenital short femur=2, tibial hemimelia=3, posteromedial tibial bowing=6 and fibular hemimelia=3. The correlations between postnatal and prenatal length ratios were high for the femur, tibia and fibula (R>0.98, P<0.0001). The relative differences in the postnatal and prenatal length ratios of these bones were small (|average|<0.026, standard deviation <0.068).

CONCLUSION

Our data indicate that the postnatal and prenatal length ratios were equivalent, supporting the constant inhibition pattern of LLD in utero, thus validating the prenatal multiplier method for predicting LLD.

Timing of Epiphysiodesis to Correct Leg-Length Discrepancy: A Comparison of Prediction Methods

BACKGROUND

The purpose of this study was to compare the accuracy of different methods used to predict ultimate leg lengths and residual leg-length discrepancy in a group of patients treated with epiphysiodesis at our institution.

METHODS

Seventy-seven patients with adequate preoperative radiographs, no postoperative complications, and follow-up to skeletal maturity composed the study group. We compared the predicted lengths of both legs and residual leg-length discrepancy at maturity with actual outcomes using the White-Menelaus, Anderson-Green, Moseley, and multiplier methods.

RESULTS

Skeletal age varied >1 year from chronological age in 61 (26%) of 231 observations, including 19 patients (25%) whose average skeletal age from 3 determinations differed by >1 year from chronological age. The prediction accuracy of each method was improved by using skeletal, rather than chronological, age. Error in prediction of the length of the short leg varied from a mean (and standard deviation) of 1.8 ± 1.2 cm for the straight-line graph to 2.5 ± 2.0 cm for the multiplier method. Prediction error for the long leg (after epiphysiodesis) varied from a mean of 1.2 ± 1.1 cm for the straight-line graph to 1.7 ± 1.5 cm for the multiplier method. Leg-length-discrepancy prediction error ranged from a mean of 0.7 ± 0.6 cm for the White-Menelaus method incorporating a growth inhibition factor to 1.1 ± 0.9 cm for the multiplier method. The multiplier method was the least accurate of all. All differences were significant.

CONCLUSIONS

Determination of skeletal age is clinically relevant in patients being considered for epiphysiodesis to manage leg-length inequality. The multiplier method was the least accurate of the prediction methods in this patient population, which may have implications in calculating the appropriate timing of epiphysiodesis.

Age- and Sex-Specific Morphologic Variations of Capital Femoral Epiphysis Growth in Children and Adolescents Without Hip Disorders

Background:

Understanding the development of the capital femoral epiphysis is essential to identify pathologic variations that may lead to cam morphology.

Purpose/Hypothesis:

The purpose of this study was to investigate the development of the capital femoral epiphysis during childhood and adolescence, with specific morphologic analysis of the peripheral growth and the metaphyseal surface of the growth plate. We hypothesized that age- and sex-dependent morphologic variations of the peripheral growth (cupping) and surface anatomy (epiphyseal tubercle) of the epiphysis would be evident with increasing age.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

Pelvic computed tomography scans of 80 children and adolescents (range, 8-15 years; n = 10 per age group; 50% male), imaged because of suspected appendicitis, were used to reformat the proximal femur. All patients had asymptomatic hips with no signs or history of hip disorder. We measured the peripheral cupping of the epiphysis and the epiphyseal tubercle dimensions from 3-dimensional models. All measurements were normalized to the epiphyseal diameter. The effect of age on these parameters was evaluated by use of linear regression analysis. A 2-way analysis of variance (ANOVA) was used to compare these parameters between males and females.

Results:

The mean epiphyseal cupping increased with increasing age (R² = 0.54; P < .001). The mean normalized epiphyseal cupping was consistently higher in the anterior and posterior directions compared with the inferior and superior locations. Male patients aged 10 and 11 years had lower (P = .002) mean epiphyseal cupping compared with female patients of the same age. We observed no difference between male and female participants after 12 years of age (P > .3). The normalized epiphyseal tubercle height (R² = 0.08; P = .009), width (R² = 0.13; P = .001), and length (R² = 0.45; P < .001) decreased with increasing age, with no differences between male and female patients. On average, a 2.6-fold increase was found in epiphyseal cupping from 8 to 15 years of age, whereas normalized tubercle height decreased by 0.4-fold.

Conclusion:

Peripheral cupping of the epiphysis over the metaphysis increases with age, while the relative epiphyseal tubercle dimensions decrease. Females have an earlier onset of rapid increase in the peripheral cupping compared with males; however, no differences in epiphyseal tubercle dimensions were found between male and female patients. These findings may guide future studies investigating the development of cam morphology, which should consider the surface morphologic characteristics of the capital femoral epiphysis, the growth plate, and the differences in morphologic characteristics according to age and sex.

Current Strategies and Future Directions to Optimize ACL Reconstruction in Adolescent Patients

The incidence of anterior cruciate ligament (ACL) injuries in the pediatric population has risen in recent years. These injuries have historically presented a management dilemma in skeletally immature patients with open physes and significant growth remaining at time of injury. While those nearing skeletal maturity may be treated with traditional, transphyseal adult techniques, these same procedures risk iatrogenic damage to the growth plates and resultant growth disturbances in younger patients with open physes. Moreover, conservative management is non-optimal as significant instabilities of the knee remain. Despite the development of physeal-sparing reconstructive techniques for younger patients, there remains debate over which procedure may be most suitable on a patient to patient basis. Meanwhile, the drivers behind clinical and functional outcomes following ACL reconstruction remain poorly understood. Therefore, current strategies are not yet capable of optimizing surgical ACL reconstruction on an individualized basis with absolute confidence. Instead, aims to improve surgical treatment of ACL tears in skeletally immature patients will rely on additional approaches in the near future. Namely, finite element models have emerged as a tool to model complex knee joint biomechanics. The inclusion of several individualized variables such as bone age, three dimensional geometries around the knee joint, tunnel positioning, and graft tension collectively present a possible means of better understanding and even predicting how to enhance surgical decision-making. Such a tool would serve surgeons in optimizing ACL reconstruction in the skeletally immature individuals, in order to improve clinical outcomes as well as reduce the rate of post-operative complications.

The effects of uninvolved side epiphysiodesis for limb length equalization in children with unilateral cerebral palsy: clinical evaluation with the Edinburgh visual gait score

PURPOSE

Hemiplegic cerebral palsy patient may present a shorten leg on the hemiplegic side that afflicts negatively the kinematic of the uninvolved limb. Thus, the aim of this study was to investigate the modification of gait kinematic after epiphysiodesis for limb equalization and secondary to verify the prediction of correction.

METHODS

Skeletally immature hemiplegic patients with a minimum limb leg discrepancy (LLD) of 2.5 cm were treated with epiphysiodesis of the unaffected knee and clinically evaluated with Edinburgh visual gait score (EVGS). Green-Anderson curve was used to predict time decision for correction.

RESULTS

Ten LLD patients were evaluated with the Edinburgh visual gait score (EVGS) before and after surgery. Mean age was 12.7 years, mean follow-up was 6.7 years, and mean LLD was 3.4 cm before surgery and 1.2 cm at final follow-up. After lower limb equalization surgery, improvement in gait kinematics was observed on both the uninvolved and hemiplegic limb of hemiplegic cerebral palsy patients (p < 0.001). Final correction did not reach expected correction (2.3 vs. 2.8 cm). However, the difference was not statistically significant (p = 0.058).

CONCLUSION

This is the first study to report improvement on both the uninvolved and hemiplegic limb gait kinematics after limb equalization surgery. Due to the impaired dorsiflexion of the hemiplegic foot, LLD target at the end of growth should range between 0.5 and 1.5 cm.

Determination and correlation of lower limb anatomical parameters and bone age during skeletal growth (based on 1005 cases)

The aim of this study was to evaluate bone age and its correlation with the lower limbs' developing skeletal anatomy during growth. 1005 children and young adults were evaluated for bone age and 14 different parameters measured on lower-limb reconstructions from radiological examinations carried out with an EOS 2D/3D system in the course of routine orthopedic indicated diagnostic practice. Cervical vertebral morphology evaluation for bone age using the Hassel-Farman method, which describes six stages of maturity, was selected. Intra- and inter-observer reliability tests for this method, and for the EOS 3D reconstructions were performed. Statistical analysis were performed using Spearman correlation, multiple linear regression, and t-test. The intra- and inter-observer reliability of the Hassel-Farman method and the EOS 3D lower-limb reconstruction were found to be excellent. Interestingly one bone age stage could include individuals across a 12.1 year range, and conversely individuals of the same calendar age could be of one of 3.2 different bone age stages. In the prepubertal age groups all six bone stages could be observed. Bone age revealed a stronger relationship, lower standard deviations with groups and proved to be a better discriminating variable than the calendar age by collodiaphyseal angle, femoral, and tibial torsion, femorotibial rotation, and mechanical tibiofemoral angle. Bone age is an indicator of skeletal maturity and may more accurately describe the growth of some lower limb parameters. As a result we suggest the consideration of bone age when evaluating lower-limb biomechanic-anatomical parameters. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1431-1441, 2017.

Anterior Cruciate Ligament Injuries in Children and Adolescents

Dramatic increases in youth competitive athletic activity, early sport specialization, and year-round training and competition, along with increased awareness of anterior cruciate ligament (ACL) injuries in children, have led to a commensurate increase in the frequency of ACL tears in the skeletally immature. Recent understanding of the risks of nonoperative treatment and surgical delay have supported a trend toward early operative treatment. This article discusses treatment strategies for ACL injuries in children and adolescents, and offers our preferred treatment strategy for skeletally immature youth athletes with ACL tears.

An improved spreadsheet for calculating limb length discrepancy and epiphysiodesis timing using the multiplier method

PURPOSE

The multiplier method is a technique to predict limb length discrepancy (LLD) at maturity in pediatric patients. Various tools have been developed for performing the multiplier calculations to predict LLD and timing of epiphysiodesis. These include multiplier/growth applications (apps) and a spreadsheet which have helped to facilitate LLC calculations in an efficient and easy manner. We have updated the spreadsheet to improve features for making LLD calculations and facilitate pasting data into electronic medical records (EMRs).

METHODS

Tools currently in use were critically examined for features that limited their function, created possible sources of error or could be more user-friendly. These features were modified and recreated in an improved Excel spreadsheet that uses patient age, sex, limb lengths, and previous lengthening surgeries as inputs to predict LLD at maturity and offer options for timing of epiphysiodesis for both congenital and developmental LLD. Our multiplier spreadsheet function was then compared to manual calculations and other multiplier tools for accuracy and ease of use.

RESULTS

Our spreadsheet accurately calculates LLD at maturity and timing of epiphysiodesis when compared to other methods. It contains a function to calculate predicted leg lengths after previous lengthenings, and concise single-page worksheets for developmental LLD, congenital LLD, and height prediction.

CONCLUSIONS

This spreadsheet was developed to provide a more efficient and user-friendly method of calculating LLD at maturity and timing of epiphysiodesis. It can easily be pasted into the EMR for ease of documentation. We recommend this method for both clinical practice and educational use.

[Special topics in pediatric orthopedics: options and limits of growth guidance]

BACKGROUND

A main task of pediatric orthopedics is the treatment of legs of different lengths or misshapen legs. Whereas for adult patients complicated and invasive operative interventions are necessary, the growth potential of the epiphysial plate can be utilized in childhood and adolescence to correct leg length differences and leg axis deformities.

THERAPY

Epiphysiodesis leads to a guidance of growth via a temporary or permanent and partial or complete blockade of the epiphysial plate depending on the indications. This method is principally a less invasive procedure with few complications.

CONCLUSION

Careful preoperative assessment of the indications and planning, precise operative technique and attentive postoperative control investigations are absolutely essential for successful treatment.