Association of Relative Skeletal Immaturity of the Triradiate Cartilage with Increased Proximal Femoral Deformity in Prophylactic Fixation for Slipped Capital Femoral Epiphysis: A Radiographic Study

INTRODUCTION

The purpose of this study was to describe proximal femoral deformity after contralateral hip prophylactic fixation of slipped capital femoral epiphysis (SCFE) in patients and the association of relative skeletal immaturity with this deformity.

METHODS

A retrospective review of patients presenting with a SCFE was conducted from 2009 to 2015. Inclusion criteria were (1) radiographic evidence of a unilateral SCFE treated with in situ fixation, (2) contralateral prophylactic fixation of an unslipped hip, and (3) at least 3 years of follow-up. Measurements were made on radiographs and included greater trochanter height relative to the center of the femoral head, femoral head-neck offset, and femoral neck length. Skeletal maturity was evaluated by assessing the status of the proximal femoral physis and triradiate cartilage (TRC) of the hip, in addition to the length of time to closure of these physes. Values were compared from initial presentation to final follow-up. Statistical analysis included descriptive statistics and linear regression.

RESULTS

Twenty-seven patients were included. Bivariable linear regression demonstrated that an increased relative trochanteric overgrowth was associated with TRC width (β = 3.048, R = 0.585, P = 0.001) and an open TRC (β = -11.400, R = 0.227, P = 0.012). Time to proximal femoral physis closure (β = 1.963, R = 0.444, P = 0.020) and TRC closure (β = 1.983, R = 0.486, P = 0.010) were predictive of increased deformity. In addition, multivariable elimination linear regression demonstrated that TRC width (β = 3.048, R = 0.585, P = 0.001) was predictive of an increased relative trochanteric overgrowth.

DISCUSSION

Patients with an open TRC and increased TRC width are associated with increased relative trochanteric overgrowth when undergoing prophylactic fixation for a unilateral SCFE. Increased caution should be exercised when considering contralateral hip prophylactic fixation in skeletally immature patients presenting with a unilateral SCFE.

LEVEL OF EVIDENCE

Level IV, case series.

Bilateral Slipped Capital Femoral Epiphysis in a Young Girl Treated With Chemotherapy: A Case Report

CASE

A 1-year-old girl was treated with chemotherapy and hematopoietic stem cell transplantation because of CD40 ligand deficiency. Four years later, she presented with pain in her right leg, diagnosed as atypical acute slipped capital femoral epiphysis, without a clear cause, besides chemotherapy possibly. She was treated with fixation of the epiphysis with a cannulated screw. Two years later, the same diagnosis was made for the left hip and the same surgery was applied. After the 2-year follow-up, clinical outcomes were good.

CONCLUSION

Chemotherapy may be a risk factor for atypical slipped capital femoral epiphysis, even without the combination with radiotherapy.

Rate and Risk Factors for Contralateral Slippage in Adolescents Treated for Slipped Capital Femoral Epiphysis: A Comprehensive Analysis of 3,528 Cases

BACKGROUND

After a unilateral slipped capital femoral epiphysis (SCFE), the contralateral hip is at risk for a subsequent SCFE. However, further information with regard to risk factors involved in the development of contralateral SCFE must be investigated. The purpose of this study was to report the rate and risk factors for subsequent contralateral SCFE in adolescents treated for unilateral SCFE by exploring a mix of known and potential risk factors.

METHODS

A case-control study utilizing aggregated multi-institutional electronic medical record data between January 2003 and March 2023 was conducted. Patients <18 years of age diagnosed with SCFE who underwent surgical management were included. Variables associated with contralateral SCFE were identified using multivariable logistic regression models that adjusted for patient characteristics and time of the surgical procedure, providing adjusted odds ratios (ORs). The false discovery rate was accounted for via the Benjamini-Hochberg method.

RESULTS

In this study, 15.3% of patients developed contralateral SCFE at a mean (and standard error) of 296.53 ± 17.23 days and a median of 190 days following the initial SCFE. Increased thyrotropin (OR, 1.43 [95% confidence interval (CI), 1.04 to 1.97]; p = 0.022), diabetes mellitus (OR, 1.67 [95% CI, 1.22 to 2.49]; p = 0.005), severe obesity (OR, 1.81 [95% CI, 1.56 to 2.57]; p < 0.001), history of human growth hormone use (OR, 1.85 [95% CI, 1.10 to 3.38]; p = 0.032), low vitamin D (OR, 5.75 [95% CI, 2.23 to 13.83]; p < 0.001), younger age in boys (under 12 years of age: OR, 1.85 [95% CI, 1.37 to 2.43]; p < 0.001) and in girls (under 11 years of age: OR, 1.47 [95% CI, 1.05 to 2.02]; p = 0.026), and tobacco exposure (OR, 2.43 [95% CI, 1.49 to 3.87]; p < 0.001) were significantly associated with increased odds of developing contralateral SCFE.

CONCLUSIONS

In the largest study on this topic, we identified the rate, odds, and risk factors associated with development of contralateral SCFE. We found younger age, hypothyroidism, severe obesity, low vitamin D, diabetes mellitus, and a history of human growth hormone use to be independent risk factors. Our findings can aid clinical decision-making in at-risk patients.

LEVEL OF EVIDENCE

Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Limited angular remodelling after in-situ fixation for slipped capital femoral epiphysis : A study on radiographs from the Swedish pediatric orthopaedic quality registry for SCFE

BACKGROUND

In Sweden, most children with slipped capital femoral epiphysis (SCFE) are operated on with a single smooth pin or a short-threaded screw, allowing further growth of the femoral neck. Using the Swedish Pediatric Orthopaedic Quality registry, SPOQ, we investigated whether angular remodelling occurs adjacent to the proximal femoral epiphysis after fixation of SCFE using implants, allowing continued growth of the femoral neck.

METHODS

During 2008-2010 a total national population of 155 children were reported to the SPOQ registry. Following our strict inclusion criteria, radiographs of 51 hips were further assessed. The lateral Head Shaft Angle (HSA), the Nötzli 3-point α-angle, the anatomic α-angle, and the Anterior Offset Ratio (AOR) on the first postoperative radiographs and at follow-up were measured to describe the occurrence of remodelling. Slip severity was categorised as mild, moderate or severe according to postoperative HSA.

RESULTS

Mean and SD values for the change in HSA were 3,7° (5,0°), for 3-point α-angle 6,8° (8,9°), and anatomic α-angle 13,0° (16,3°). The overall increase in AOR was 0,038 (0.069). There were no significant differences between the slip severity groups.

CONCLUSIONS

We found limited angular remodelling after in situ fixation with smooth pins or short threaded screws for SCFE. The angular remodelling and the reduction of the CAM deformity was less than previously described after fixation of SCFE with similar implants. Results about the same magnitude with non-growth sparing techniques suggest that factors other than longitudinal growth of the femoral neck are important for angular remodelling.

[Evaluation of care for slipped capital femoral epiphysis (SCFE) in Germany]

INTRODUCTION

The treatment concept for slipped capital femoral epiphysis is still controversial. According to studies, there is currently no recommendation for a universal approach. Therefore, the aim of this study is to analyze the care reality of children with ECF in Germany.

METHODS

The evaluation of the study is performed based on a questionnaire sent to physicians tending to ECF in 2021. Data is compared to the literature.

RESULTS

36 of 47 questionnaires sent out were included. Overall, no significant difference in ECF care was proven in terms of annual caseload or the size of hospital.

CONCLUSION

A high variance in operative SCFE treatment is reported. According to current literature, the modified Dunn procedure is considered the best therapeutic option to date, especially for patients with severe or chronic ECF. However, compared with alternative care options, this is not feasible in every hospital due to its complicating and challenging nature. Central registration, minimum volume regulation, and expansion of continuing education measures can contribute to optimization.

In situ fixation of slipped capital femoral epiphysis carries a greater than 40% risk of later total hip arthroplasty during a long-term follow-up

Aims

We aimed to assess the cumulative risk of total hip arthroplasty (THA) from in situ fixation for slipped capital femoral epiphysis (SCFE) after a follow-up of almost 50 years.

Methods

In this study, 138 patients with 172 affected hips treated with in situ fixation were evaluated retrospectively. A total of 97 patients (70%) were male and the mean age was 13.6 years (SD 2.1); 35 patients (25%) had a bilateral disease. The median follow-up time was 49 years (interquartile range 43 to 55). Basic demographic, stability, and surgical details were obtained from patient records. Preoperative radiographs (slip angle; SA) were measured, and data on THA was gathered from the Finnish National Arthroplasty Register.

Results

The preoperative SA was a mean of 39° (SD 19°). At follow-up, 56 of the patients had undergone THA for a hip previously fixed in situ for SCFE (41%) and 64 of all affected hips had been replaced (37%). Kaplan-Meier analysis gave a median prosthesis-free postoperative survival of 55 years (95% confidence interval (CI) 45 to 64) for the affected hips. In a multivariate analysis, female patients had a two-fold risk for THA (hazard ratio (HR) 2.42 (95% CI 1.16 to 5.07)) and a greater preoperative SA increased the risk of THA (HR 1.03 for every increment of 1° (95% CI 1.01 to 1.05)), while patient age at surgery, slip laterality, stability of slip, or diagnostic delay did not have a statistically significant effect on the risk of THA.

Conclusion

SCFE treated primarily with in situ fixation may lead to THA in more than 40% of affected hips at a near 50-year follow-up. This risk is approximately 15-times the reported lifetime risk in the Finnish general population. Female sex and increasing preoperative SA significantly predicted higher risk of THA.

[Clinical aspects of imaging the hip in infants, children and adolescents]

When a child with a hip problem is clinically evaluated, it is usually possible to make a presumptive diagnosis which is subsequently confirmed. The most important tool for confirmation in pediatric hip disorders is radiological imaging. Vice versa changes on sonogram, native X‑ray or magnetic resonance images (MRI) can often only be interpreted when the history and current clinical findings are known. In this constellation, it is desirable that all colleagues who are confronted with a child's hip problem know the most common and important pediatric hip disorders and use the same terminology. The aim of this article is to present a short outline of the pathogenesis and clinical aspects of congenital and neurogenic hip dysplasia, coxitis fugax, septic coxitis, Perthes' disease, infantile and adolescent femoroacetabular impingement, apophysiolyses, and slipped capital femoral epiphysis.

Surgeon Preference for Prophylactic Contralateral Fixation in Slipped Capital Femoral Epiphysis (SCFE) Patients: A Nationwide POSNA Survey Study

BACKGROUND

It is estimated that 11% to 60% of unilateral slipped capital femoral epiphysis (SCFE) patients will develop contralateral pathology, usually within 18 months after the first event. Despite this, prophylactic fixation remains controversial, and there is significant variability in surgeon preferences. Thus, this study aimed to determine which factors predict surgeon preferences for prophylactic contralateral pinning in SCFE patients.

METHODS

We designed a survey for pediatric orthopedic surgeons to collect data on (1) surgeon and hospital characteristics, (2) individual preference for contralateral SCFE pinning in three disparate hypothetical scenarios, and (3) personal risk-aversion traits. The questionnaire was distributed across the United States by the POSNA Evidence-Based Orthopaedics Committee. All POSNA members were eligible to respond. We performed analyses to evaluate the role of patient risk factors in hypothetical surgical decision-making and to determine if surgical training, hospital characteristics, and geographic region influenced prophylactic pinning in a surgeon's real-life practice.

RESULTS

A total of 126 POSNA members responded to the survey. In the last year, a median of 6.5 SCFE patients was seen per surgeon (1243 patients total). A median of 10% of those patients underwent prophylactic contralateral fixation. In multiple analyses, surgeons were influenced by body mass index, open triradiate cartilage, patient race, various endocrine abnormalities, and specific radiographic measurements when deciding to fix the contralateral side prophylactically. Moreover, in multivariate regression, more years in practice and a hospital size of 500+ beds predicted fewer prophylactic fixation procedures (all P <0.05). Surgeons practicing in the South Atlantic, New England, and Mountain regions of the United States estimated the highest rate of contralateral pinning.

CONCLUSIONS

This study's findings suggest that multiple factors influence surgeons' decisions to prophylactically fix the contralateral side in SCFE patients. Surgical training, hospital characteristics, and geographical regions played a role in decision-making.

LEVEL OF EVIDENCE

N/A.

[Slipped capital femoral epiphysis]

BACKGROUND

In slipped capital femoral epiphysis (SCFE), the femoral head slides in an anterosuperior direction along the growth plate. The femoral head remains in the acetabulum. The pathogenesis of SCFE is multifactorial. An important predisposing factor is obesity.

PROBLEM

Epiphysiolysis can compromise the blood supply to the epiphysis and osteonecrosis of the femoral head may result.

DIAGNOSTICS AND PROGNOSIS

Conventional radiography represents the first diagnostic step. The long-term prognosis of the disease depends on the residual deformity of the femoral head and in the worst case may result in early osteoarthritis of the hip joint.

Comparison of three radiographic assessment methods for detecting slipped capital femoral epiphyses in cats: Klein's line, modified Klein's line and the S-sign

OBJECTIVES

The aim of the present study was to investigate whether diagnostic assessment methods used on radiographs in humans with slipped capital femoral epiphysis (SCFE) can be used in cats.

METHODS

The ventrodorsal (VD) extended-leg and VD frog-leg pelvic radiographs of 20 cats with SCFE without fully displaced femoral capital epiphyses (FCE), eight cats with fully displaced FCE and five control cats with normal pelvic anatomy were assessed by five observers on two separate occasions 3 months apart. The Klein's line and modified Klein's line were assessed on each VD extended-leg radiograph, and the S-sign was assessed on each VD extended-leg and VD frog-leg radiograph.

RESULTS

Excluding cases of fully displaced FCE, the S-sign on the VD frog-leg radiographs more accurately diagnosed SCFE than the S-sign on the VD extended-leg radiographs and the Klein's line (92.4% vs 88.8% vs 60.6%, respectively), and had the greatest sensitivity (93.9% vs 79.2% vs 30.6%, respectively). The S-sign on the VD extended-leg radiographs had greater specificity than the Klein's line and S-sign on the VD frog-leg radiographs (99.2% vs 97.9% vs 90.9%, respectively). The modified Klein's line detected SCFE in 40.2% of cases that were negative for the Klein's line.

CONCLUSIONS AND RELEVANCE

The S-sign in both VD extended-leg and VD frog-leg views successfully detected SCFE in cats and can be used to increase early diagnosis and treatment in cats with SCFE that have only subtle radiographic changes.

Effects of joint loading on the development of capital femoral epiphysis morphology

INTRODUCTION

The deleterious influence of increased mechanical forces on capital femoral epiphysis development is well established; however, the growth of the physis in the absence of such forces remains unclear. The hips of non-ambulatory cerebral palsy (CP) patients provide a weight-restricted (partial weightbearing) model which can elucidate the influence of decreased mechanical forces on the development of physis morphology, including features related to development of slipped capital femoral epiphysis (SCFE). Here we used 3D image analysis to compare the physis morphology of children with non-ambulatory CP, as a model for abnormal hip loading, with age-matched native hips.

MATERIALS AND METHODS

CT images of 98 non-ambulatory CP hips (8-15 years) and 80 age-matched native control hips were used to measure height, width, and length of the tubercle, depth, width, and length of the metaphyseal fossa, and cupping height across different epiphyseal regions. The impact of age on morphology was assessed using Pearson correlations. Mixed linear model was used to compare the quantified morphological features between partial weightbearing hips and full weightbearing controls.

RESULTS

In partial weightbearing hips, tubercle height and length along with fossa depth and length significantly decreased with age, while peripheral cupping height increased with age (r > 0.2, P < 0.04). Compared to normally loaded (full weightbearing) hips and across all age groups, partially weightbearing hips' epiphyseal tubercle height and length were smaller (P < .05), metaphyseal fossa depth was larger (P < .01), and posterior, inferior, and anterior peripheral cupping heights were smaller (P < .01).

CONCLUSIONS

Smaller epiphyseal tubercle and peripheral cupping with greater metaphyseal fossa size in partial weightbearing hips suggests that the growing capital femoral epiphysis requires mechanical stimulus to adequately develop epiphyseal stabilizers. Deposit low prevalence and relevance of SCFE in CP, these findings highlight both the role of normal joint loading in proper physis development and how chronic abnormal loading may contribute to various pathomorphological changes of the proximal femur (i.e., capital femoral epiphysis).

Which factor is more reliable considering prophylactic pinning of contralateral hip of unilateral SCFE patients?

BACKGROUND

This study evaluates the radiological parameters of developing subsequent contralateral slips in unilateral slipped capital femoral epiphysis (SCFE) patients at the time of initial presentation.

METHODS

The study group included the review of unilateral SCFE patients treated between June 2007 and August 2018. Age, gen-der, side, stability, posterior slope angle, grade of slip, modified Oxford bone age score (mOBAS), the Risser classification, and the ap-pearance of the triradiate cartilage were evaluated retrospectively. Data were analyzed between two groups: subsequent contralateral SCFE (SCFESC) patients that developed contralateral slip during follow-up and unilateral SCFE (SCFEU) patients that did not develop contralateral slip up to skeletal maturity. Descriptive statistics were used to compare risk factors between groups.

RESULTS

This study included 48 patients and 6 patients (12.5%) developed a SCFESC. Only mOBAS was significantly different be-tween groups. The mOBAS scores in SCFESC were 18 in 2 patients (33.3%), 19 in 4 patients (66.7%). The mOBAS scores in SCFEU were 18 in 1 patient (2.4%), 19 in 24 patients (57.1%), and >20 in 17 patients (40.5%). In the SCFESC group, all patients had a Risser score of 0 and all had open triradiate cartilage.

CONCLUSION

Patients with unilateral SCFE are at risk for SCFESC, and the mOBAS is the best predictor of risk assessment. We agree that mOBAS score of 16,17 or 18 patients' contralateral hips can be prophylactically pinned. We also suggest pinning or close screening of mOBAS 19 patients that some carry relatively high risk of subsequent contralateral slip.

Who Benefits From Allowing the Physis to Grow in Slipped Capital Femoral Epiphysis?

BACKGROUND

The globally acknowledged treatment for mild to moderate slipped capital femoral epiphysis (SCFE) is single screw in situ fixation, also used for prophylactic contralateral fixation. The Free-Gliding Screw (FG; Pega Medical) is a 2-part free-extending screw system designed to allow the growth of the proximal femur. We aimed to analyze the relationship between skeletal maturity and potential growth of the proximal physis and remodeling of the femoral neck using this implant.

MATERIALS AND METHODS

Females below 12 years and males below 14 years undergoing in situ fixation for stable SCFE or prophylactic fixation were treated using the implant. Three elements of the modified Oxford Bone (mOB 3 ) score were used to measure maturity (triradiate cartilage, head of the femur, and greater trochanter). Radiographs were analyzed immediately postoperatively and at a minimum of 2 years for a change in screw length, posterior-sloping angle, articulotrochanteric distance, α angle, and head-neck offset.

RESULTS

The study group comprised 30 (F:M=12:18) of 39 hips treated with SCFE and 22 (F:M=13:9) of 29 hips managed prophylactically using the free-Gliding screw. In the therapeutic group, chronologic age was a less valuable predictor of future screw lengthening than mOB 3 . An mOB 3 of ≤13 predicted future growth of >6 mm but did not reach statistical significance ( P =0.07). Patients with open triradiates showed a mean screw lengthening of 6.6 mm compared with those with closed triradiates (4.0 mm), but this did not reach significance ( P =0.12). In those with mOB 3 ≤13, the α angle reduced significantly ( P <0.01) and the head-neck offset increased significantly, suggesting remodeling. There was no change in these parameters when mOB 3 ≥14. In the prophylactic group, change in screw length was significant with mOB 3 of ≤13 (mean=8.0 mm, P <0.05), as was the presence of an open triradiate cartilage (mean=7.7 mm, P <0.05). In both cohorts, posterior-sloping angle and articulotrochanteric distance did not change, indicating no slip progression in either treatment or prophylactic groups and minimal effect on the proximal physeal growth relative to the greater trochanter.

CONCLUSIONS

Growing screw constructs can halt slip progression while allowing proximal femoral growth in young patients with SCFE. Ongoing growth is better when the implant is used for prophylactic fixation. The results in treated SCFE need to be expanded to demonstrate a clinically meaningful cut-off for significant growth, but SCFE patients with an open triradiate remodel significantly more than those where it is closed.

LEVEL OF EVIDENCE

Level III-retrospective comparative study.

Can we still use X-rays to predict contralateral slip in primary unilateral slipped capital femoral epiphysis?

The objective of this study was to assess subsequent contralateral slip (SCS) in the unaffected hip in patients with primary unilateral slipped capital femoral epiphysis (SCFE) using three radiographic parameters: posterior sloping angle (PSA), center-edge angle (CEA) and triradiate cartilage (TC) appearance. A total of 152 patients admitted to two pediatric units between 2001 and 2015 were divided into three groups: A - underwent prophylactic fixation of the unaffected hip at the time of index surgery- high clinical risk of SCS; B - no clinical risk factors but SCS occurred; C - no issues regarding the contralateral hip during follow-up. The mean PSA for groups A, B and C were 22°(6-49), 17°(9-24) and 13°(0-27), respectively. PSA was significantly higher in Group A than in Group C ( P < 0.0001). The differences in PSA between groups A and B, but also B and C were insignificant ( P = 0.12 and p=0.21, respectively). The mean CEA in groups A, B and C was 33(25-43), 35(26-42) and 37(17-53), respectively. CEA did not differ significantly between groups A, B and C ( P = 0.25). Assessment of TC did not differ significantly between the groups ( P = 0.66). Observation of TC in groups B and C combined revealed that the cartilage was open in 65% of 77 patients and 14% of them developed SCS; whereas among the 35% of patients with ossified TC only 7% developed SCS (OR=2.0). PSA and CEA alone have no predictive value in determining the risk of contralateral slip. The absence of TC results in a two-fold decrease in the likelihood of developing an SCS. The decision of prophylactic surgical treatment of the contralateral hip in primary unilateral SCFE should not be based solely on radiographic findings.

Femoroacetabular impingement in the unpinned contralateral hip in patients with primary unilateral slipped capital femoral epiphysis: preliminary radiographic outcomes

The study evaluated femoroacetabular impingement (FAI) in the unpinned contralateral hip in patients with unilateral slipped capital femoral epiphysis (SCFE) and verified initial age, posterior sloping angle (PSA) and center-edge angle (CEA) as predictors of FAI in the contralateral hip. 152 patients with unilateral SCFE with a mean index age of 13.2 years (8.2-17.2 years) were enrolled retrospectively into the study. Mean follow-up was 8 years (3-14 years). PSA and CEA were measured on initial radiographs of the unaffected hip. Alpha-angle and CEA were measured on radiographs taken at the last follow-up to identify FAI. Four groups of patients were distinguished: (1) no FAI (10 patients, 17.54%); (2) CAM-type FAI (41 patients, 71.9%); (3) pincer-type FAI (3 patients, 5.26%) and (4) mixed-type FAI (13 patients, 22.8%). The mean PSA was 12.1°, 12°, 16.8°, 11.9° for groups 1, 2, 3 and 4, respectively, with no significant difference ( P  = 0.65). The mean initial CEA for groups 1, 2, 3 and 4 was 34.4°, 35.5°, 42° and 42° respectively, with significant differences between groups 1 versus 4 ( P  = 0.034) and 2 versus 4 ( P  = 0.009). Conclusions are as follows: 1. Radiographic features of FAI were present in 85.1% of unpinned contralateral hips in patients with unilateral SCFE. 2. 71.9% of unpinned contralateral hips developed CAM deformity. 3. CEA can be used in predicting pincer-type FAI in the contralateral hip in unilateral SCFE. 4. PSA and age revealed negligible value in predicting FAI.

A Comparison Between 3 Functional Hip Scores for Evaluation of the Pediatric Hip

BACKGROUND

This investigation aimed to determine the degree of correlation among 3 functional scales for evaluating the hip in pediatric patients and determine the correlation between measures of global function and outcome.

METHODS

We performed a prospective study of 173 consecutive patients (M age = 13 ± 3 y) being followed for developmental dysplasia of the hip (n = 122, 71%), slipped capital femoral epiphysis (n = 31, 18%), or Legg-Calve-Perthes disease (n = 20, 12%). We evaluated patients clinically, and we compiled scores for the Iowa Hip Score (IHS), Harris Hip Score (HHS), and Children's Hospital Oakland Hip Evaluation Scale (CHOHES). Patients concomitantly completed the Pediatric Outcomes Data Collection Instrument (PODCI) at the same clinic visit. We assessed Global Functioning Scale the and the Sports and Physical Functioning Core Scale of the PODCI. We determined the degree of correlation between the functional hip scales and between each scale and the PODCI scales using Spearman rank correlation coefficients.

RESULTS

The correlations between the IHS, HHS, and CHOHES scores were robust (IHS and HHS ρ = 0.991; IHS and CHOHES ρ = 0.933; HHS and CHOHES ρ = 0.938; all P < 0.001). The correlation between the Global Functioning Scale of the PODCI and the 3 hip scores was ρ = 0.343 for the IHS, ρ = 0.341 for the HHS, and ρ = 0.352 for the CHOHES (all P < 0.001). The correlation between the sports and physical functioning core scale of the PODCI and the 3 hip scores was ρ = 0.324 for the IHS, ρ = 0.329 for the HHS, and ρ = 0.346 for the CHOHES (all P < 0.001).

CONCLUSIONS

In a pediatric population with diverse hip pathology, there was a very strong correlation between scores on the IHS, HHS, and CHOHES. However, none of these 3 most commonly used hip scores correlated strongly with the global functioning scale or sports and physical functioning core scale of the PODCI. The most frequently used scores to determine the outcome of pediatric patients with hip pathology correlate strongly with each other but do not necessarily relate to global functional results.

LEVEL OF EVIDENCE

Level IV.

Skeletal Outcomes in Children and Young Adults with Glomerular Disease

BACKGROUND

Children with glomerular disease have unique risk factors for compromised bone health. Studies addressing skeletal complications in this population are lacking.

METHODS

This retrospective cohort study utilized data from PEDSnet, a national network of pediatric health systems with standardized electronic health record data for more than 6.5 million patients from 2009 to 2021. Incidence rates (per 10,000 person-years) of fracture, slipped capital femoral epiphysis (SCFE), and avascular necrosis/osteonecrosis (AVN) in 4598 children and young adults with glomerular disease were compared with those among 553,624 general pediatric patients using Poisson regression analysis. The glomerular disease cohort was identified using a published computable phenotype. Inclusion criteria for the general pediatric cohort were two or more primary care visits 1 year or more apart between 1 and 21 years of age, one visit or more every 18 months if followed >3 years, and no chronic progressive conditions defined by the Pediatric Medical Complexity Algorithm. Fracture, SCFE, and AVN were identified using SNOMED-CT diagnosis codes; fracture required an associated x-ray or splinting/casting procedure within 48 hours.

RESULTS

We found a higher risk of fracture for the glomerular disease cohort compared with the general pediatric cohort in girls only (incidence rate ratio [IRR], 1.6; 95% CI, 1.3 to 1.9). Hip/femur and vertebral fracture risk were increased in the glomerular disease cohort: adjusted IRR was 2.2 (95% CI, 1.3 to 3.7) and 5 (95% CI, 3.2 to 7.6), respectively. For SCFE, the adjusted IRR was 3.4 (95% CI, 1.9 to 5.9). For AVN, the adjusted IRR was 56.2 (95% CI, 40.7 to 77.5).

CONCLUSIONS

Children and young adults with glomerular disease have significantly higher burden of skeletal complications than the general pediatric population.

Pediatric patient with a bilateral Salter-Harris II fracture and slipped capital femoral epiphysis secondary to autosomal recessive osteopetrosis

Treatment of femoral neck fractures secondary to osteopetrosis is an uncertain and puzzled decision. Experience in the treatment, especially in the pediatric population, is scarcely reported. The duration of conservative treatment is prolonged and poses the risks of non-union and development of coxa vara deformity. The recommended treatment is closed reduction and internal fixation; however, surgery on osteopetrotic bone is challenging due to defective bone marrow function, delayed consolidation and higher risk of intraoperative fractures. Slipped capital femoral epiphysis secondary to osteopetrosis is very rarely reported. This article presents the case of a 5-year-old female patient with rapidly deteriorating physical function due to bilateral proximal femoral Salter-Harris type II fractures with associated slippage of the growth plates secondary to confirmed autosomal recessive osteopetrosis. Operative treatment was performed in a tertiary level orthopedic center with closed reduction and internal fixation with cannulated screws. A loss of fixation with coxa vara deformity was seen on the left side 7 months postoperatively with increasing pain. A revision surgery with reosteosynthesis and a valgus osteotomy was thus performed which showed good subjective and objective results 1 year postoperatively with complete bony union.

A review of slipped capital femoral epiphysis

ABSTRACT

Hip pain in children is common, with causes ranging from the benign to destructive. This article reviews slipped capital femoral epiphysis (SCFE), one of the most common hip pathologies in preadolescents and adolescents, which often is missed or delayed in diagnosis because of its vague, atypical presentation.

Limited Hip Flexion and Internal Rotation Resulting From Early Hip Impingement Conflict on Anterior Metaphysis of Patients With Untreated Severe SCFE Using 3D Modelling

INTRODUCTION

Slipped capital femoral epiphysis (SCFE) is the most common hip disorder in adolescent patients that can result in complex 3 dimensional (3D)-deformity and hip preservation surgery (eg, in situ pinning or proximal femoral osteotomy) is often performed. But there is little information about location of impingement.Purpose/Questions: The purpose of this study was to evaluate (1) impingement-free hip flexion and internal rotation (IR), (2) frequency of impingement in early flexion (30 to 60 degrees), and (3) location of acetabular and femoral impingement in IR in 90 degrees of flexion (IRF-90 degrees) and in maximal flexion for patients with untreated severe SCFE using preoperative 3D-computed tomography (CT) for impingement simulation.

METHODS

A retrospective study involving 3D-CT scans of 18 patients (21 hips) with untreated severe SCFE (slip angle>60 degrees) was performed. Preoperative CT scans were used for bone segmentation of preoperative patient-specific 3D models. Three patients (15%) had bilateral SCFE. Mean age was 13±2 (10 to 16) years and 67% were male patients (86% unstable slip, 81% chronic slip). The contralateral hips of 15 patients with unilateral SCFE were evaluated (control group). Validated software was used for 3D impingement simulation (equidistant method).

RESULTS

(1) Impingement-free flexion (46±32 degrees) and IRF-90 degrees (-17±18 degrees) were significantly ( P <0.001) decreased in untreated severe SCFE patients compared with contralateral side (122±9 and 36±11 degrees).(2) Frequency of impingement was significantly ( P <0.001) higher in 30 and 60 degrees flexion (48% and 71%) of patients with severe SCFE compared with control group (0%).(3) Acetabular impingement conflict was located anterior-superior (SCFE patients), mostly 12 o'clock (50%) in IRF-90 degrees (70% on 2 o'clock for maximal flexion). Femoral impingement was located on anterior-superior to anterior-inferior femoral metaphysis (between 2 and 6 o'clock, 40% on 3 o'clock and 40% on 5 o'clock) in IRF-90 degrees and on anterior metaphysis (40% on 3 o'clock) in maximal flexion and frequency was significantly ( P <0.001) different compared with control group.

CONCLUSION

Severe SCFE patients have limited hip flexion and IR due to early hip impingement using patient-specific preoperative 3D models. Because of the large variety of hip motion, individual evaluation is recommended to plan the osseous correction for severe SCFE patients.

LEVEL OF EVIDENCE

Level III.

Controlled repositioning and primary osteoplasty as a treatment option for the management of unstable slipped capital femoral epiphysis

The ideal management of an unstable slipped capital femoral epiphysis (SCFE) is still controversial. The currently available options are in-situ screw fixation with delayed corrective osteotomy, closed reduction and screw fixation and anatomic reduction by modified Dunn's procedure (MDP). We present the results of our technique of controlled re-positioning (CRP) with primary osteoplasty in which the epiphysis is repositioned to the preacute slip stage and a mini-open osteoplasty is done in the same sitting to avoid later femoro-acetabular impingement. We had 27 unstable slips which presented to our institution between 2015 and 2019, of which nine were treated with the above technique, and the rest 18 were treated with MDP. All of them were followed up for a minimum of 1 year. The mean intraoperative flexion-internal rotation before osteoplasty was -21.1° (-5° to -40°), which improved to +22.8° (+15° to +30°). Pre- and post-operative mean head-neck angles were 46.5° and 18.3°, respectively, with a decrease of 28.2°. At the final follow-up, the mean alpha angle was 45.1° and the mean head-neck offset ratio was 0.26. None of the patients had avascular necrosis or chondrolysis. The technique of CRP, screw fixation and primary osteoplasty is a viable treatment option for a subset of patients with unstable SCFEs. But, the decision is made intraoperatively and the parents need to be counselled about the need for an alternative procedure if repositioning is unsuccessful. Level of evidence: level IV - case series.

Proximal femoral changes related to obesity: an analysis of slipped capital femoral epiphysis pathoanatomy

Recent research has revealed the importance of the femoral epiphyseal tubercle and cupping height in the stability of the physis and its association with capital femoral slippage. To better understand the connection between the pathogenesis of slipped capital femoral epiphysis and obesity, we performed a retrospective analysis of proximal femur and acetabular anatomies using computed tomography (CT) scans in the hips of normal weight and obese pediatric patients. We measured morphologic characteristics of the proximal femur and acetabulum in developing hips of 31 obese adolescent patients and age-matched and sex-matched control group using pelvic CT scans. Measurements included physeal diameter, tubercle height, width, and volume, cupping height, acetabular rotation and inclination, and metaphyseal bone density. Measurements were performed on true coronal and sagittal views through the center of the epiphysis using previously described and validated techniques. Statistical analysis was performed to compare the measurements between obese and nonobese adolescents. The epiphyseal tubercle volume and average cupping size were similar between the two groups. Acetabular inclination and metaphyseal bone density were significantly different between the cohorts. Metaphyseal bone density was lower among obese patients. Obesity does not appear to cause morphologic changes to the capital femoral physis, though it is associated with a decreased metaphyseal bone mineral density which could indicate physeal instability. This could suggest increased metabolic activity in the metaphyseal bone in obese adolescents. Therefore, metabolic factors associated with obesity, rather than anatomical changes, may be responsible for physeal instability seen in obese adolescents.

Telescoping screw fixation compared to traditional in situ screw fixation for slipped capital femoral epiphysis: clinical, radiographic and patient-reported outcomes

This study compares clinical, radiographic and patient-reported outcomes among telescoping and traditional screws for the treatment of slipped capital femoral epiphysis (SCFE). We hypothesized that telescoping screws would prevent slip progression and result in preserved femoral neck growth and improved patient-reported outcomes. Traditional screws were compared to telescoping screws in a 2:1 matched cohort based on age at initial surgery, length of radiographic follow-up and whether or not the hip was pinned prophylactically or as a treatment for SCFE. Neck length and telescoping screw length were measured. The patient-reported outcomes were obtained at routine clinic visits. Total 42 hips were included with a mean follow-up of 24.5 ± 3.3 months. No patients developed avascular necrosis, chondrolysis or needed revision surgical procedures. Telescoping screws increased in length for the entire cohort by a mean of 6.0 ± 4.3 mm. Neck length change was not different in SCFE hips when treated with traditional screws vs. telescoping screws (P = 0.527). However, there was a difference in neck length change between the two groups when comparing prophylactically treated hips (P = 0.001). There were no significant differences in patient-reported outcomes among hips treated with telescoping screws compared to traditional screws. Traditional and telescoping screws are both effective for the treatment of SCFE. Telescoping screws have an advantage when prophylactically treating hips that are at risk of slipping as they don't lead to the coxa breva that is seen with traditional screws. However, both treatment methods had similar patient-reported outcomes.

Surgical treatment of slipped capital femoral epiphysis (SCFE) by Dunn procedure modified by Ganz: a systematic review

BACKGROUND

Treatment of SCFE is still controversial, especially in moderate and severe forms. Dunn osteotomy performed with the Ganz approach became very popular in the last decade, although it is a complicated and challenging surgical procedure with a risk of AVN. The aim of our study was to analyze the current literature verifying the effectiveness of this surgical procedure, with specific attention to the incidence of AVN and other complications.

MAIN BODY

A systematic review on the subject was performed according to the PRISMA guidelines. A literature search was performed by searching all published articles about the topic in the databases. The articles were screened for the presence of the following inclusion criteria: patients affected by slipped capital femoral epiphysis (SCFE) surgically treated by Dunn osteotomy using the Ganz surgical approach. All the patients affected by pathologies other than SCFE, treated without surgery or with procedures not including a surgical hip dislocation were excluded. Based on inclusion and exclusion criteria, 23 studies were included in our systematic review. Selected articles were published from 2009 to 2021 and they included 636 overall hips. According to the selected articles, Dunn osteotomy modified by Ganz, performed by an experienced surgeon, allows for anatomical reduction of moderate or severe SCFE with a low incidence of AVN.

CONCLUSIONS

The few papers with long term follow-up, reported no progression of hip osteoarthritis, however, since the patients are adolescent at surgery, longer follow-up studies are needed to validate this statement. It is still debated if better results are obtained in stable or unstable SCFE. The indication of this procedure in mild SCFE remains controversial.

LEVEL OF EVIDENCE

3.

Slipped capital femoral epiphysis with hypopituitarism in adults: A case report and literature review

RATIONALE

Slipped capital femoral epiphysis (SCFE) is a common disease in pediatric orthopedics. Most research on SCFE has focused on high-risk groups or the whole population, and studies focusing on adult SCFE patients are rare. In the present study, we report the case of an adult patient with SCFE.

PATIENT CONCERN

A 37-year-old man presented to our clinic with persistent pain that was poorly localized to both hips, groin regions, and thighs for more than 1 year.

DIAGNOSES

A bilateral hip X-ray examination was performed, and the femoral epiphyses were found to be unfused on both sides. Low levels of growth hormone (GH), insulin-like growth factor-1 (IGF-1), triiodothyronine (T3), thyroxine (T4), follicle-stimulating hormone, luteinizing hormone, estradiol, and testosterone, and high levels of thyroid-stimulating hormone, prolactin, and cortisol.

INTERVENTIONS

Hormone-substitution therapies (levothyroxine sodium to treat hypothyroidism and testosterone enanthate to treat hypogonadism) were prescribed. Total hip arthroplasty was performed to treat femoral epiphysis slippage.

OUTCOMES

After 6 months of postoperative follow-up, the patient's gait improved significantly, and bilateral hip pain was relieved.

LESSONS

When treating adults with SCFE, clinicians must be alert to endocrine disorders. Comprehensive imaging evaluation is crucial for the accurate diagnosis and selection of an appropriate treatment.

Slipped capital femoral epiphysis

Slipped capital femoral epiphysis is a paediatric hip disorder that affects around 30 children in Norway each year. The symptoms are a limping gait and pain in the hip or knee. The condition is diagnosed by normal x-ray and treatment is surgical. It is essential to make the diagnosis as quickly as possible, and children with persistent hip symptoms should be rapidly examined by means of a hip x-ray.

Outcomes of distally un-threaded screw fixation of slipped capital femoral epiphysis at skeletal maturity: a matched cohort study

The most common treatment for slipped capital femoral epiphysis worldwide is in situ fixation with a threaded screw. Un-threaded screws are designed to prevent slip progression without hindering residual growth of the proximal femur. This study aimed to compare growth, remodelling and long-term outcomes after fixation with un-threaded screws and a matched cohort of patients treated with a standard screw. Six patients (nine hips) treated with un-threaded screws and 16 patients (21 hips) treated with standard screws matched for age, skeletal maturity, sex and Southwick angle were recruited. Clinical records were reviewed for patient demographics, medical history and complications. Radiographs were reviewed for residual growth and time to physeal closure. Growth velocity was calculated. Absence of cam deformity signified complete remodelling. Clinical assessment was graded from excellent to poor and patient-reported outcomes were recorded. There was significantly more growth recorded in the un-threaded screw group in femoral neck length (7.6 mm, P = 0.003), articulo-lesser trochanter distance (5.3 mm, P = 0.028), pin-joint ratio (7.439%, P = 0.006) and pin-physis ratio (8.244%, P = 0.001). The probability of revision operations due to ongoing growth was higher in this group (risk ratio: 6.57, P = 0.0008). Time to physeal closure was not significantly different, but growth velocity was significantly higher in the un-threaded group. The lower probability of cam deformity was not significant. Functional and clinical results were not significantly different at average 11.2 years' follow-up. Un-threaded screws allow for significantly more growth than standard threaded screws. The un-threaded screw could not be recommended due to the higher re-operation rates, without any proven benefit.

Modified Oxford Bone Scores Are Reduced in Patients With Slipped Capital Femoral Epiphysis Compared With Healthy Controls

BACKGROUND

The etiology and pathogenesis of slipped capital femoral epiphysis (SCFE) are attributable to abnormalities of the proximal femoral epiphysis. This study aimed to examine if there is a difference in the bone age of patients diagnosed with SCFE compared with patients without hip pathology.

METHODS

We identified a consecutive series of patients treated for SCFE between December 2012 and December 2019 from a departmental database. Retrospective chart review was performed to collect demographic information and patient medical history. We then obtained a control group of statistically similar patients based on age and sex. These patients did not have hip pathology or medical comorbidities that could alter their bone age. The modified Oxford bone score (mOBS) was calculated for both groups by 3 blinded reviewers. We excluded patients with unstable slips, endocrine disorders, and inadequate imaging.

RESULTS

We identified 60 patients with stable idiopathic SCFE during the study period; 45 met inclusion criteria and were included in the final analysis. There were 27 males and 18 females. The average age of patients with SCFE was higher in males than females (12.6 vs. 11.1, P<0.01). Patients in the comparison cohort did not differ significantly from the SCFE cohort in terms of age (11.6 vs. 12.0, P=0.06) or sex (P=0.52). The comparison group's median mOBS was significantly higher than the SCFE group (22.5 vs. 20.5, P<0.01). The difference in the mOBS between male and female patients in the SCFE group approached significance (20.0 vs. 21.0, P=0.05). The weighted κ coefficient was 0.93.

CONCLUSIONS

Patients with SCFE have a decreased bone age compared with patients without hip pathology. Male patients with SCFE were more likely to be older compared with female patients.

LEVEL OF EVIDENCE

Level IV-retrospective study.

Low bone mineral density on DXA and slipped capital femoral epiphysis as rare presentation in a child with Rubinstein-Taybi syndrome

We present a 7-year-old girl with Rubinstein-Taybi syndrome (RTS) and slipped capital femoral epiphysis (SCFE). She underwent bilateral arthroscopy with implant fixation for the SCFE and the symptoms resolved. This was followed by fracture of the femur after minor trauma. Dual energy X-ray absorptiometry (DXA) scan done to evaluate her bone health revealed a low bone mineral density (BMD). Our case highlights the finding of low BMD on DXA and rare association of SCFE in a child with RTS. The conundrum in this case is whether this child can be labelled to have osteoporosis as defined by the criteria given by the International Society for Clinical Densitometry guidelines.

Slipped Capital Femoral Epiphysis in an Adult with Panhypopituitarism: A Case Report

CASE

Our patient was a 31-year-old woman with previously undiagnosed panhypopituitarism who presented with bilateral slipped capital femoral epiphysis (SCFE). Together with endocrinology, her treatment plan involved medical management of her panhypopituitarism and surgical correction with femoral neck osteotomy. Hormone deficiencies were corrected 6 weeks after replacement therapy began, and the patient was cleared for surgery. By 5 months after osteotomy, examination revealed delayed union and prominent screws bilaterally. Hardware exchange and repeat internal fixation were then performed. At 8 weeks after revision, she presented with avascular necrosis, and the decision was made to proceed with total hip arthroplasty. A 5-year follow-up period was documented.

CONCLUSION

This case presented a rare look at SCFE in an adult patient with panhypopituitarism. Other systemic illnesses that can contribute to SCFE or other orthopaedic issues include, but are not limited to, multiple endocrine neoplasia syndromes, vitamin D deficiency, renal osteodystrophy, Kallmann syndrome, Klinefelter syndrome, and pathologies affecting the thyroid and pituitary gland.

Diagnosis and Management of Unstable Slipped Capital Femoral Epiphysis: A Critical Analysis Review

»

An unstable slipped capital femoral epiphysis (SCFE) is characterized by the inability to walk and is associated with a high risk of osteonecrosis.

»

An unstable SCFE is less common than a stable SCFE; however, the demographics are similar in both groups of patients with SCFE.

»

The diagnosis of an unstable SCFE is characterized by a history of antecedent pain and the inability to walk on examination, and it is confirmed by radiographic assessment.

»

Management of an unstable SCFE includes closed reduction, open reduction, and capital realignment, which have all been noted to have lower rates of osteonecrosis than reported in historic reports.

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All management approaches have certain advantages and disadvantages, and comparative studies are needed to guide clinical decision-making.

[Knee pain in a child : watch out for the hip !]

This is a case report of a 13-year old patient presenting with knee pain after a bike accident. Multiple investigations and medical examinations focused on the knee. They did not show any abnormality. About one year later, the patient comes back with increased hip pain, limited internal rotation and shortening of the left limb. Hip X-Ray exams reveal a bilateral slipped capital femoral epiphysis requiring already an osteotomy. Slipped capital femoral epiphysis is a disorder of the proximal femoral epiphysis. The femoral neck is displaced anteriorly and rotates externally while the epiphysis remains in the acetabulum. This pathology is more common in preadolescent boys and can be associated with hormonal disorders. Patients present with an externally rotated gait, a limited internal rotation, associated hip and knee pain. Diagnosis might be missed when patients present with knee pain and can lead to delayed treatment. When facing knee pain, it is essential to perform a clinical examination of the hip. Radiography is the first medical imaging. Surgical treatment by in situ fixation is recommended and prevents further slip with a high rate of success. When delayed, a much more invasive approach is required. A delay in diagnosis adversely affects long-term outcomes.

Slipped capital femoral epiphysis: an epidemiological Nationwide study in Italy from 2001 to 2015

BACKGROUND

Slipped capital femoral epiphysis (epiphysiolysis of the femoral head, SCFE) is the most common pediatric hip disease in 10-14 years old children. The most used procedure to correct a stable form of SCFE is in situ pinning. Instead, the proper treatment for unstable forms is controversial. The first purpose of this study was to estimate annual admissions for SCFE in Italian patients from 2001 to 2015, basing on the hospitalization reports. The second aim was to assess the difference between regions regarding SCFE procedures. Lastly, a statistical prediction of the volume of SCFE procedures performed in Italy based on data from 2001 to 2015 was performed.

METHODS

Data of this study were collected from the National Hospital Discharge Reports (SDO) reported at the Italian Ministry of Health regarding the years of this paper. The yearly number of hospital admission for SCFE, the percentage of males and females, the average age, days of hospitalization, primary diagnoses and primary procedures in the whole Italian population were calculated using descriptive statistical analyses.

RESULTS

From 2001 to 2015, 4893 hospitalizations for SCFE were recorded in Italy, with a mean incidence of 2.9 (cases/100.000 inhabitants). The majority of patients treated by SCFE were males (70.6%).

CONCLUSION

National health statistics for SCFE are attractive for an international audience, as different approaches to screening are reported between countries. These differences allow comparing outcomes internationally. Moreover, sharing national statistics and correlating those to other countries protocols, could be helpful to compare outcomes for different procedures internationally. However, further studies are required to understand the specific reasons for regional variation for SCFE procedures in Italy.

LEVEL OF EVIDENCE

III.

What Is the Association Among Epiphyseal Rotation, Translation, and the Morphology of the Epiphysis and Metaphysis in Slipped Capital Femoral Epiphysis?

BACKGROUND

Contemporary studies have described the rotational mechanism in patients with slipped capital femoral epiphysis (SCFE). However, there have been limited patient imaging data and information to quantify the rotation. Determining whether the epiphysis is rotated or translated and measuring the epiphyseal displacement in all planes may facilitate planning for surgical reorientation of the epiphysis.

QUESTIONS/PURPOSES

(1) How does epiphyseal rotation and translation differ among mild, moderate, and severe SCFE? (2) Is there a correlation between epiphyseal rotation and posterior or inferior translation in hips with SCFE? (3) Does epiphyseal rotation correlate with the size of the epiphyseal tubercle or the metaphyseal fossa or with epiphyseal cupping?

METHODS

We identified 51 patients (55% boys [28 of 51]; mean age 13 ± 2 years) with stable SCFE who underwent preoperative CT of the pelvis before definitive treatment. Stable SCFE was selected because unstable SCFE would not allow for accurate assessment of rotation given the complete displacement of the femoral head in relation to the neck. The epiphysis and metaphysis were segmented and reconstructed in three-dimensions (3-D) for analysis in this retrospective study. One observer (a second-year orthopaedic resident) performed the image segmentation and measurements of epiphyseal rotation and translation relative to the metaphysis, epiphyseal tubercle, metaphyseal fossa, and the epiphysis extension onto the metaphysis defined as epiphyseal cupping. To assess the reliability of the measurements, a randomly selected subset of 15 hips was remeasured by the primary examiner and by the two experienced examiners independently. We used ANOVA to calculate the intraclass and interclass correlation coefficients (ICCs) for intraobserver and interobserver reliability of rotational and translational measurements. The ICC values for rotation were 0.91 (intraobserver) and 0.87 (interobserver) and the ICC values for translation were 0.92 (intraobserver) and 0.87 (intraobserver). After adjusting for age and sex, we compared the degree of rotation and translation among mild, moderate, and severe SCFE. Pearson correlation analysis was used to assess the associations between rotation and translation and between rotation and tubercle, fossa, and cupping measurements.

RESULTS

Hips with severe SCFE had greater epiphyseal rotation than hips with mild SCFE (adjusted mean difference 21° [95% CI 11° to 31°]; p < 0.001) and hips with moderate SCFE (adjusted mean difference 13° [95% CI 3° to 23°]; p = 0.007). Epiphyseal rotation was positively correlated with posterior translation (r = 0.33 [95% CI 0.06 to 0.55]; p = 0.02) but not with inferior translation (r = 0.16 [95% CI -0.12 to 0.41]; p = 0.27). There was a positive correlation between rotation and metaphyseal fossa depth (r = 0.35 [95% CI 0.08 to 0.57]; p = 0.01), width (r = 0.41 [95% CI 0.15 to 0.61]; p = 0.003), and length (r = 0.56 [95% CI 0.38 to 0.75]; p < 0.001).

CONCLUSION

This study supports a rotational mechanism for the pathogenesis of SCFE. Increased rotation is associated with more severe slips, posterior epiphyseal translation, and enlargement of the metaphyseal fossa. The rotational nature of the deformity, with the center of rotation at the epiphyseal tubercle, should be considered when planning in situ fixation and realignment surgery. Avoiding placing a screw through the epiphyseal tubercle-the pivot point of rotation- may increase the stability of the epiphysis. The realignment of the epiphysis through rotation rather than simple translation is recommended during the open subcapital realignment procedure. Enlargement of the metaphyseal fossa disrupts the interlocking mechanism with the tubercle and increases epiphyseal instability. Even in the setting of a stable SCFE, an increased fossa enlargement may indicate using two screws instead of one screw, given the severity of epiphyseal rotation and the risk of instability. Further biomechanical studies should investigate the number and position of in situ fixation screws in relation to the epiphyseal tubercle and metaphyseal fossa.

LEVEL OF EVIDENCE

Level III, prognostic study.

Does a History of Slipped Capital Femoral Epiphysis in Patients Undergoing Femoroacetabular Osteoplasty for Femoroacetabular Impingement Affect Outcomes Scores or Risk of Reoperation?

BACKGROUND

Femoroacetabular impingement (FAI) can occur after slipped capital femoral epiphysis (SCFE) regardless of slip severity and even after in situ pinning. These patients represent a rare and unique demographic that is largely unreported on. It is important to further characterize the clinical presentation of these patients, associated treatment modalities, and the efficacy of these treatment modalities.

QUESTIONS/PURPOSES

(1) How do patients with post-SCFE FAI typically present in terms of radiographic and surgical findings? (2) How do their hip-specific and general-health outcomes scores after mini-open femoroacetabular osteoplasty compare with those obtained in a matched group of patients with FAI caused by other etiologies? (3) How do those groups compare in terms of the proportion who undergo conversion to THA?

METHODS

Between 2013 and 2017, 20 patients had femoroacetabular osteoplasty for post-SCFE FAI. During that time, general indications for this procedure were symptomatic FAI demonstrated on radiographs and physical exam. Of those, none was lost to follow-up before a minimum of 2 years, leaving all 20 available for matching, and all 20 had suitable matches in our database for patients who underwent femoroacetabular osteoplasty for other diagnoses. Matching was performed by surgeon, patient age, patient gender, and BMI. The matching group was drawn from a large database of patients who had the same procedure during the same period. We matched in a 1:3 ratio to arrive at 60 randomly selected control patients in this retrospective, comparative study. Patient demographics, medical history, clinical presentation, radiographic parameters, and intraoperative findings were compared between the two groups. At a minimum of 2 years of follow-up, the latest clinical functional outcome scores (Hip Disability and Osteoarthritis Outcome Score Jr and SF-12) and proportions of conversion to THA were compared between the groups.

RESULTS

A greater percentage of patients with a history of SCFE than those without prior SCFE demonstrated full chondral lesions intraoperatively (90% [18 of 20] versus 32% [19 of 60], odds ratio 7 [95% confidence interval 1 to 178]; p < 0.01). A greater percentage of patients with a history of SCFE also demonstrated labral calcifications intraoperatively compared with those without prior SCFE (65% [13 of 20] versus 35% [21 of 60], OR 3 [95% CI 1 to 10]; p = 0.04). Radiographically, patients with SCFE had greater preoperative alpha angles than did patients without SCFE (94° ± 13° versus 72° ± 22°; p = 0.01) as well as lower lateral center-edge angles (25° ± 8° versus 31° ± 8°; p = 0.04). There was no difference in postoperative follow-up between patients with a history of SCFE and patients without a history of SCFE (4 ± 2 years versus 4 ± 2 years; p = 0.32). There was no difference in the mean postoperative outcome scores between patients with a history of SCFE and patients without (Hip Disability and Osteoarthritis Outcome Score Jr: 75 ± 28 points versus 74 ± 17 points; p = 0.95; SF-12 physical score: 40 ± 11 points versus 39 ± 8 points; p = 0.79). There was no difference with the numbers available in the percentage of patients who underwent conversion to THA (15% [3 of 20] versus 12% [7 of 60], OR 1.36 [95% CI 0 to 6]; p = 0.71).

CONCLUSION

Patients with FAI after SCFE present with a greater degree of labral and chondral disease than do patients without a history of SCFE. However, at short-term follow-up, the proportion of patients who underwent conversion to THA and patients' postoperative outcome scores did not differ in this small, comparative series between patients with and without SCFE. Further evaluation with long-term follow-up is needed, especially given the more severe chondral damage we observed in patients with SCFE at the time of surgery.

LEVEL OF EVIDENCE

Level III, therapeutic study.

How Common Is Femoral Retroversion and How Is it Affected by Different Measurement Methods in Unilateral Slipped Capital Femoral Epiphysis?

BACKGROUND

Although femoral retroversion has been linked to the onset of slipped capital femoral epiphysis (SCFE), and may result from a rotation of the femoral epiphysis around the epiphyseal tubercle leading to femoral retroversion, femoral version has rarely been described in patients with SCFE. Furthermore, the prevalence of actual femoral retroversion and the effect of different measurement methods on femoral version angles has yet to be studied in SCFE.

QUESTIONS/PURPOSES

(1) Do femoral version and the prevalence of femoral retroversion differ between hips with SCFE and the asymptomatic contralateral side? (2) How do the mean femoral version angles and the prevalence of femoral retroversion change depending on the measurement method used? (3) What is the interobserver reliability and intraobserver reproducibility of these measurement methods?

METHODS

For this retrospective, controlled, single-center study, we reviewed our institutional database for patients who were treated for unilateral SCFE and who had undergone a pelvic CT scan. During the period in question, the general indication for obtaining a CT scan was to define the surgical strategy based on the assessment of deformity severity in patients with newly diagnosed SCFE or with previous in situ fixation. After applying prespecified inclusion and exclusion criteria, we included 79 patients. The mean age was 15 ± 4 years, 48% (38 of 79) of the patients were male, and 56% (44 of 79) were obese (defined as a BMI > 95th percentile (mean BMI 34 ± 9 kg/m2). One radiology resident (6 years of experience) measured femoral version of the entire study group using five different methods. Femoral neck version was measured as the orientation of the femoral neck. Further measurement methods included the femoral head's center and differed regarding the level of landmarks for the proximal femoral reference axis. From proximal to distal, this included the most-proximal methods (Lee et al. and Reikerås et al.) and most-distal methods (Tomczak et al. and Murphy et al.). Most proximally (Lee et al. method), we used the most cephalic junction of the greater trochanter as the landmark and, most distally, we used the center base of the femoral neck superior to the lesser trochanter (Murphy et al.). The orientation of the distal femoral condyles served as the distal reference axis for all five measurement methods. All five methods were compared side-by-side (involved versus uninvolved hip), and comparisons among all five methods were performed using paired t-tests. The prevalence of femoral retroversion (< 0°) was compared using a chi-square test. A subset of patients was measured twice by the first observer and by a second orthopaedic resident (2 years of experience) to assess intraobserver reproducibility and interobserver reliability; for this assessment, we used intraclass correlation coefficients.

RESULTS

The mean femoral neck version was lower in hips with SCFE than in the contralateral side (-2° ± 13° versus 7° ± 11°; p < 0.001). This yielded a mean side-by side difference of -8° ± 11° (95% CI -11° to -6°; p < 0.001) and a higher prevalence of femoral retroversion in hips with SCFE (58% [95% CI 47% to 69%]; p < 0.001) than on the contralateral side (29% [95% CI 19% to 39%]). These differences between hips with SCFE and the contralateral side were higher and ranged from -17° ± 11° (95% CI -20° to -15°; p < 0.001) based on the method of Tomczak et al. to -22° ± 13° (95% CI -25° to -19°; p < 0.001) according to the method of Murphy et al. The mean overall femoral version angles increased for hips with SCFE using more-distal landmarks compared with more-proximal landmarks. The prevalence of femoral retroversion was higher in hips with SCFE for the proximal methods of Lee et al. and Reikerås et al. (91% [95% CI 85% to 97%] and 84% [95% CI 76% to 92%], respectively) than for the distal measurement methods of Tomczak et al. and Murphy et al. (47% [95% CI 36% to 58%] and 60% [95% CI 49% to 71%], respectively [all p < 0.001]). We detected mean differences ranging from -19° to 4° (all p < 0.005) for 8 of 10 pairwise comparisons in hips with SCFE. Among these, the greatest differences were between the most-proximal methods and the more-distal methods, with a mean difference of -19° ± 7° (95% CI -21° to -18°; p < 0.001), comparing the methods of Lee et al. and Tomczak et al. In hips with SCFE, we found excellent agreement (intraclass correlation coefficient [ICC] > 0.80) for intraobserver reproducibility (reader 1, ICC 0.93 to 0.96) and interobserver reliability (ICC 0.95 to 0.98) for all five measurement methods. Analogously, we found excellent agreement (ICC > 0.80) for intraobserver reproducibility (reader 1, range 0.91 to 0.96) and interobserver reliability (range 0.89 to 0.98) for all five measurement methods in healthy contralateral hips.

CONCLUSION

We showed that femoral neck version is asymmetrically decreased in unilateral SCFE, and that differences increase when including the femoral head's center. Thus, to assess the full extent of an SCFE deformity, femoral version measurements should consider the position of the displaced epiphysis. The prevalence of femoral retroversion was high in patients with SCFE and increased when using proximal anatomic landmarks. Since the range of femoral version angles was wide, femoral version cannot be predicted in a given hip and must be assessed individually. Based on these findings, we believe it is worthwhile to add evaluation of femoral version to the diagnostic workup of children with SCFE. Doing so may better inform surgeons as they contemplate when to use isolated offset correction or to perform an additional femoral osteotomy for SCFE correction based on the severity of the slip and the rotational deformity. To facilitate communication among physicians and for the design of future studies, we recommend consistently reporting the applied measurement technique.

LEVEL OF EVIDENCE

Level III, prognostic study.

Valgus slipped capital femoral epiphysis: presentation, treatment, and clinical outcomes using patient-reported measurements

Valgus slipped capital femoral epiphysis (SCFE), is rare. This study describes the diagnosis, treatment and outcome of valgus SCFE in Uruguay. The medical records and radiographs were reviewed in eight consecutive children [mean age 11.9 years (range 9-13; six female)] with valgus SCFE between 1997-2017. In 2018-2019, all patients were reexamined clinically, new radiographs obtained, and patient-reported outcomes completed using the international tool of hip results (iHOT-12). The prevalence of clinical femoroacetabular impingement (FAI), avascular necrosis, and surgical complications were also studied. There were 11 valgus SCFEs in eight patients; two had primary bilateral SCFEs, and one child later developed a valgus SCFE in the contralateral hip. Seven out of eight patients were overweight. All were stable idiopathic SCFEs. The mean femoral head shaft angle on the anteroposterior radiographs for the 11 SCFEs was 145° (range 140-168) and 141° (range 139-145) for the six healthy contralateral hips. Slip severity measured on the Lauenstein projection was mild (<30°) in eight hips and moderate (30°-60°) in three hips. At a mean follow-up of 87 months (range 24-252), there were no cases of avascular necrosis. The mean iHOT12 was 74 (range 13-97). Significant remodeling was detected in both head shaft angle (8°) and alpha angle (10°) in the affected hips. Nine hips (81%) demonstrated clinical signs of FAI. Our study is the first to describe long-term results using both clinical and patient outcome measures (iHOT-12). A majority of patients have residual symptoms, likely associated with FAI.

Purposeful Closed Reduction and Pinning in Unstable Slipped Capital Femoral Epiphysis Results in a Rate of Avascular Necrosis Comparable to the Literature Mean

The standard treatment of stable slipped capital femoral epiphysis (SCFE) is generally accepted to be in situ pinning. Controversy exists regarding the treatment of unstable SCFE, including the role of a purposeful closed reduction or open reduction. The objective of this study was to investigate the rate of avascular necrosis (AVN) with purposeful closed reduction and in situ pinning of unstable SCFE. The authors retrospectively reviewed 221 patients with 302 SCFE hips treated with in situ pinning between 2000 and 2014. Forty-eight patients (50 hips) presented with an unstable SCFE. All unstable SCFEs were treated by a gentle reduction method with traction and hip internal rotation followed by pinning. Southwick angles were measured prior to reduction and at the first postoperative visit. No stable SCFEs developed AVN. Thirteen (26%) unstable SCFEs developed AVN. Avascular necrosis developed in 7 of 17 (41%) hips screened with magnetic resonance imaging vs 6 of 33 (18%) hips screened with plain radiographs alone. Mean change in Southwick angle was 28°±8° in the AVN group vs 18°±18° in the no AVN group (P=.18). Despite potentially inflating the rate with the use of early detection magnetic resonance imaging, the authors found an AVN rate comparable to that in the published literature with the use of gentle purposeful reduction on a fracture table, and no statistical differences in reduction amount between patients with and without AVN. Gentle purposeful reduction appears to be a reasonable low morbidity option in the treatment of unstable SCFE without a clear increase in risk of AVN. [Orthopedics. 2021;44(2):92-97.].

The characteristics of the whole pelvic morphology in slipped capital femoral epiphysis: A retrospective observational study

Slipped capital femoral epiphysis (SCFE) is a very common disorder affecting the adolescent hip. The etiology of SCFE is multifactorial and mechanical force associated with the characteristic morphology of the hip is considered one of the causes of SCFE. We investigated the characteristics of whole pelvic morphology including pelvic incidence (PI) in patients with SCFE and compared it with pelvic morphology in healthy children. We retrospectively assessed the whole pelvic morphology of 17 patients with SCFE and 51 healthy children using their pelvic computed tomography data. We measured superior iliac angle, inferior iliac angle, and ischiopubic angle as the parameters of pelvic rotation. Additionally, we measured acetabular anteversion of the superior acetabulum (AVsup) and of the center of the acetabulum (AVcen), and measured anterior acetabular sector angle (AASA), posterior acetabular sector angle, and the superior acetabular sector angle (SASA) as parameters of acetabular coverage and PI. Each measurement was compared between the 2 groups. AASA and SASA of patients with SCFE were significantly greater than that of controls, and AVsup of patients with SCFE was significantly smaller. There were no significant differences in pelvic rotation, PI, or AVcen between the 2 groups. This is the 1st report to evaluate SCFE patients' whole pelvic morphology including PI and pelvic rotation. Our results showed that patients with SCFE have excessive coverage of the anterior and superior acetabulum, and a more retroverted cranial acetabulum as compared with healthy control subjects. Such characteristic pelvic morphology may be involved in the onset of SCFE. To clarify the mechanical forces involved in SCFE onset, further investigations of pelvic morphology and alignment, including the femur and spine, are needed.

The Atypical Patient With Slipped Capital Femoral Epiphyses May Be at Increased Risk for a Missed Contralateral Slip

Slipped capital femoral epiphysis (SCFE) is a commonly encountered hip disorder. The goal of this study was to describe the incidence of missed contra-lateral SCFE as well as to identify risk factors. The authors hypothesized that contralateral slips are more often missed in patients with severe involvement of the treated side. After institutional review board approval was obtained, a retrospective chart review was performed of all pediatric patients who were treated for sequential and bilateral SCFE at a single institution during an 18-year period. Medical records were reviewed for demographic features and attending surgeon. Radiographs were reviewed for skeletal maturity, Klein's line, and severity of the treated slip. All radiographs were reviewed by 3 pediatric orthopedists. Contralateral SCFE was deemed present when consensus was achieved. Comparisons were made with Fisher's exact test, and P<.05 was considered significant. Of the records that were reviewed, 56 patients met the study criteria. Of these, 19 patients had bilateral involvement and 5 missed slips were identified (8.9%). The patients with missed disease tended to be younger (mean age, 10.8 vs 11.4 years), with a lower body mass index. Fellowship-trained pediatric surgeons were more likely to identify bilateral disease compared with orthopedists without pediatric training (P=.0065). A contralateral slip was more likely to be present in patients who had a positive finding for Klein's line (P<.0001). Severity of the treated slip did not increase the likelihood of missing a contralateral slip. Although Klein's line is a useful tool in the diagnosis of SCFE, a false-negative rate of 40% was observed. The authors recommend increased vigilance when an "atypical" patient with SCFE presents with unilateral disease. [Orthopedics. 2020;43(2):e114-e118.].

Clinical and radiological outcomes of chronic severe slipped capital femoral epiphysis patients treated by surgical dislocation and modified Dunn osteotomy: Case series

OBJECTIVES

This study aims to evaluate the clinical and radiological outcomes of patients with chronic severe slipped capital femoral epiphysis (SCFE) treated by surgical dislocation and modified Dunn osteotomy (MDO).

PATIENTS AND METHODS

This retrospective study, conducted between January 2010 and December 2017, included nine patients (8 males, 1 female; mean age 12.6 years; range, 7 to 16 years) with nine hips. The degree of corrections in Southwick angle and alpha angle were measured on frog-leg views. Range of motion (ROM) of the hips was measured at each follow-up visit. Heyman and Herndon classification system and Harris Hip Score (HHS) were evaluated for clinical and functional outcomes at the latest follow-up visit.

RESULTS

The mean follow-up time was 34.8 months. Avascular necrosis complication was observed in one hip. Except two patients with lateral femoral cutaneous neuropathy, none of the patients suffered from any other complications. Mean preoperative Southwick angle of 59.1° was corrected to an angle of -0.8° postoperatively. Alpha angles were calculated as 44.6° postoperatively. Modified Dunn osteotomy resulted in marked improvement in hip ROM in all directions and increased HHS.

CONCLUSION

Our results encourage us to use this method in treating SCFE patients with chronic severe slips.

Slipped capital femoral epiphysis in an adult with congenital hypopituitarism: A case report

RATIONALE

Slipped capital femoral epiphysis (SCFE) is a common hip problem in adolescents, usually individuals between 8 and 15 years old. Because of the frequent finding of growth abnormalities in affected children, various endocrine disturbances have been reported as the cause of the disease. However, there are few case reports of older patients in previous literature. To the best of our knowledge, congenital hypopituitarism with normal growth hormone (GH) level has not been reported.

PATIENT CONCERNS

We describe a 29-year-old man who had a 3-month history of pain in the left hip with tall stature and unobvious secondary sexual characteristics. Laboratory testing showed low thyroxine, low cortisol, low follicle-stimulating hormone, low luteinizing hormone, low testosterone, but normal GH.

DIAGNOSES

Brain magnetic resonance imaging showed pituitary hypoplasia. An anteroposterior pelvis radiograph showed severe varus SCFE in the left hip, it was also confirmed with computed tomography scans.

INTERVENTIONS

The patient was treated with levothyroxine, hydrocortisone, and testosterone replacement therapy before surgery. We performed open reduction and anatomical reduction by Dunn's procedure.

OUTCOME

We have followed this patient for 6 months, the left hip mobility gradually improved. No slip in the contralateral proximal femoral physis has been observed.

LESSONS

When unobvious secondary sexual characteristics and body abnormalities were found in clinical practice, endocrine condition should be evaluated, since the contralateral side may prone to slip due to the lack of endocrine therapy.

Outcome of pinning in patients with slipped capital femoral epiphysis: risk factors associated with avascular necrosis, chondrolysis, and femoral impingement

Objective This study aimed to assess the principal risk factors that could lead to the most common long-term complications of slipped capital femoral epiphysis, such as avascular necrosis, chondrolysis, and hip impingement. Methods We conducted a single-centre, retrospective study and evaluated patients (70 patients, 81 hips) who were treated for slipped capital femoral epiphysis from 2010 to 2015 and who underwent pinning. We measured the severity of displacement radiologically using the Southwick angle. Postoperative radiographs were evaluated for the most frequent long-term complications of avascular necrosis (AVN), chondrolysis, and femoral acetabular impingement (FAI). Results We found seven cases of AVN, 14 cases of chondrolysis, and 31 hips had an α angle of 60°. Sex, ambulation, and symptoms did not affect development of these complications. Patients with a normal weight were almost two times more likely to develop FAI. Patients with moderate and severe slips had a similar percentage of AVN. In severe slips, 85.7% of patients had an α angle higher than 60°. Conclusions This study shows that severe slips have a higher risk of developing AVN and hip impingement. Every patient who suffers from SCFE (even the mildest forms) should be regularly checked for FAI.