Slipped capital femoral epiphysis and its association with endocrine, metabolic and chronic diseases: a systematic review of the literature

[Safety considerations for the clinical application of recombinant human growth hormone]

Recombinant human growth hormone (rhGH) is an effective therapeutic drug for improving short stature. Currently, rhGH can be used for various causes of short stature, including growth hormone deficiency, and the expansion of its clinical application has raised concerns about its safety. Based on existing evidence, when rhGH is used in a standardized manner for physiological replacement therapy, its safety profile is favorable. In clinical practice, attention should be focused on short-term safety during rhGH treatment, with the combination of literature evidence and clinical experience. There is still no definitive conclusion on the long-term safety due to insufficient duration of rhGH treatment. This paper reviews the possible adverse events that may occur during rhGH treatment and their risk control measures, aiming to help clinical physicians understand the overall safety of rhGH treatment and improve its clinical standardization.

A Role for Thyroid Testing in Slipped Capital Femoral Epiphysis? 32% Rate of Abnormal Values in Tested Patients

BACKGROUND

Hypothyroidism is a known risk factor for slipped capital femoral epiphysis (SCFE), and prior studies of hypothyroid-associated SCFE have demonstrated an incidence of up to 6%. However, there is limited evidence and no formal practice guidelines regarding whether patients presenting with SCFE should undergo screening for endocrine disorders. This study aims to investigate the incidence of abnormal thyroid function studies in patients presenting with SCFE.

METHODS

This was a retrospective review of all patients aged 0 to 18 years treated for SCFE at a single pediatric hospital from January 2015 to July 2022. On presentation, patients' BMI, thyroid-stimulating hormone (TSH), free T4, vitamin D, creatinine, BUN, and HbA1c levels were documented. Follow-up and treatment for any identified endocrinopathies were noted. In addition, the chronicity, stability, and severity of their slips were recorded.

RESULTS

Ninety-eight patients with 106 hips were included in this study. TSH was obtained at the time of initial presentation in 66% (n=65/98) of patients. Median TSH was 2.99 (range: 0.02 to 919, std dev: 132.4). The normal reference range for our institution is 0.5 to 4.5 mcIU/mL. Thirty-two percent (n=21/65) of patients with a documented TSH had an abnormal value. Of those patients who had an elevated TSH, 3 were diagnosed with clinical hypothyroidism and went on to treatment with levothyroxine (n=3/19, 16%), 2 patients had been started on levothyroxine before presentation (n=2/19, 11%), and 2 patients were followed in endocrinology clinic until their TSH levels had normalized without further intervention (n=2/19, 11%).

CONCLUSIONS

Screening of our SCFE population revealed a 32% incidence of thyroid abnormalities which affected treatment in 24% of those patients. This is a much higher incidence of hypothyroid-associated SCFE than previously demonstrated in the literature and has prompted us to start including thyroid screening studies as a routine part of our workup for all patients with SCFE.

LEVEL OF EVIDENCE

Level III.

The Effect of Human Growth Hormone Treatment on the Development of Slipped Capital Femoral Epiphysis: A Cohort Analysis With 6 Years of Follow-up

BACKGROUND

Slipped capital femoral epiphysis (SCFE) is a common hip disorder in adolescents that can result in substantial complications, impacting the quality of life. Human Growth Hormone (HGH) administration may elevate the risk of SCFE, though the relationship remains unclear. Clarifying this association could enable better monitoring and earlier diagnosis of SCFE in patients receiving HGH. The aim of the study is to investigate the association between HGH administration and the incidence of SCFE.

METHODS

This retrospective cohort study utilized data from the TriNetX research database from January 2003 to December 2022. The study included 2 cohorts: an HGH cohort including 36,791 patients aged below 18 years receiving HGH therapy and a control group consisting of patients who did not receive HGH therapy. A 1:1 propensity score matching technique was employed to ensure comparability between the HGH and no-HGH cohorts. The primary outcome measure was the development of SCFE identified by International Classification of Diseases codes. For comparative analysis, both risk ratios (RR) and hazard ratios were computed to evaluate the association between HGH therapy and the development of SCFE.

RESULTS

The HGH cohort had an increased risk of SCFE compared with the no-HGH cohort (RR: 3.5, 95% CI: 2.073, 5.909, P <0.001) and had an increased hazard of developing SCFE (hazard ratio: 2.627, 95% CI: 1.555, 4.437, P <0.001). Patients with higher exposure to HGH (defined as >10 prescriptions) had an RR of 1.914 (95% CI: 1.160, 3.159, P =0.010) when compared with their counterparts with ≤10 prescriptions.

CONCLUSIONS

In the largest study to date, HGH administration was associated with an elevated risk of SCFE in children in a dose-dependent manner.

LEVEL OF EVIDENCE

Level III-therapeutic retrospective cohort study.

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.

Incidence and Clinical Characteristics of Slipped Capital Femoral Epiphysis in Patients with Endocrinopathy: A Population-Based Cohort Study

BACKGROUND

Endocrinopathy is a risk factor for slipped capital femoral epiphysis (SCFE). We aimed to determine (1) the incidence of endocrinopathy-associated SCFE compared with that of non-endocrinopathy-associated SCFE, (2) whether the incidence of SCFE increases with the number of deficient hormones, and (3) the clinical characteristics of endocrinopathy-associated SCFE.

METHODS

We conducted a population-based cohort study using a nationwide database in South Korea. All new diagnoses of endocrinopathy or SCFE between 2002 and 2019 in children born between 2002 and 2005 were identified. The incidence of SCFE was calculated for each type of endocrinopathy. The trend of the incidence of SCFE relative to the number of deficient hormones was analyzed. The male:female ratio was compared between endocrinopathy-associated SCFE and non-endocrinopathy-associated SCFE. For endocrinopathy-associated SCFE, the time between the diagnoses of SCFE and endocrinopathy was evaluated.

RESULTS

The incidence of SCFE was higher in children with endocrinopathy than in those without endocrinopathy (37.1/100,000 versus 9.0/100,000 children) (relative risk, 4.1 [95% confidence interval, 2.8-6.1]). Among various endocrinopathies, growth hormone deficiency showed the highest incidence of SCFE (583.8/100,000 children). The Cochran-Armitage test showed a linear trend, with an increased number of deficient hormones being associated with a higher incidence of SCFE (p < 0.001). Male sex was dominant in the non-endocrinopathy-associated SCFE group (73%; 117 of 161), whereas female sex was dominant in the endocrinopathy-associated SCFE group (53%; 16 of 30) (p = 0.009). Twenty-two of the 30 cases of endocrinopathy-associated SCFE were diagnosed after the diagnosis of endocrinopathy, with a median time of 3.6 years between the diagnoses. Six (27%) of these 22 children developed SCFE >5 years after the diagnosis of endocrinopathy.

CONCLUSIONS

The incidence of SCFE was approximately 4 times higher in children with endocrinopathy than in those without endocrinopathy. The risk of SCFE increased with an increased number of deficient hormones. Long-term monitoring of SCFE occurrence in children with endocrinopathies is strongly recommended.

LEVEL OF EVIDENCE

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

Quantifying Risk Factors for Slipped Capital Femoral Epiphysis and Postslip Osteonecrosis

BACKGROUND

Slipped capital femoral epiphysis (SCFE) is a disorder of the proximal femoral physis occurring in late childhood and adolescence. Previously postulated risk factors include obesity and endocrinopathies. The purpose of this investigation was to identify risk factors for developing SCFE, as well as postslip osteonecrosis (ON), among the United States pediatric population.

METHODS

A national database investigation was performed using PearlDiver Technologies, Inc., queried for SCFE and ON using International Classification of Disease codes (2010 to 2020). Regression analyses to determine the risk of developing a SCFE, and ON after a patient has already been diagnosed with a SCFE ("postslip"). Propensity matching between SCFE and control groups generated a pseudo-randomization model to compare the relative risk.

RESULTS

There were 11,465 patients with SCFE available in the database, matched with 134,680 controls. After matching, vitamin D deficiency, obesity, hypothyroidism, and growth hormone use were risk factors for developing SCFE [relative risk ranges from 1.42 (95% CI: 1.21-1.39, vitamin D deficiency) to 3.45 (95% CI: 3.33-3.57, obesity)]. ON risk factors were vitamin D deficiency [1.65 (1.26-2.14)] and hypothyroidism [1.49 (1.10-2.07)].

CONCLUSIONS

This United States national database study quantified risk factors of developing an SCFE and postslip ON. Obesity is the most significant risk factor for the development of a slip, but not ON. Growth hormone use, hypothyroidism, and vitamin D deficiency are also risk factors for SCFE development, whereas only the latter two were associated with ON. These findings demonstrate the public health implications of obesity and comorbid conditions in pediatric hip pathology.

LEVEL OF EVIDENCE

Level III.

Diagnosis of Slipped Capital Femoral Epiphysis: How to Stay out of Trouble?

Slipped capital femoral epiphysis (SCFE) is the most common hip disorder affecting children and adolescents aged between 9 and 16 years, affecting approximately 10 per 100,000 children per year. The diagnosis of SCFE is often delayed, leading to an increased risk of complications. This study aims to provide the latest evidence concerning the causes of diagnostic delay and risk factors for SCFE and to educate general practitioners and paediatricians to help reduce delays in diagnosis and provide earlier therapeutic intervention. A literature search was conducted in the ScienceDirect and PubMed databases according to the PRISMA statement. Suitable studies for this systematic review included 22 articles discussing the aetiology of SCFE, risk factors, and causes of late diagnosis. Causes of delayed diagnosis include underestimation by patients, initial diagnostic approach by a non-orthopaedic professional, inadequate imaging, failure to recognize morphological changes, and variation in symptomatic presentation. The underlying risk factors for SCFE are likely part of a multifactorial process which involves anatomical variations and the metabolism of leptin, growth hormone, insulin, and other metabolic parameters. This review highlights the importance of early recognition and diagnosis of SCFE and proposes an algorithm for physicians to approach children who may have this condition.

Slipped Capital Femoral Epiphysis Pathogenesis and Its Relation to Obesity—Where Do We Stand? A Narrative Review

Slipped capital femoral epiphysis (SCFE) is the most common adolescent hip disorder in children 9–15 years old with an incidence that ranges from 0.33:100,000 to 24.58:100,000. Idiopathic SCFE is strongly associated with obesity, while atypical SCFE is associated with endocrinopathies, metabolic and renal disease, radiation therapy, and chemotherapy. In this review, we summarized the current data regarding the pathogenesis of SCFE and its association to obesity. In the last years, there have been increasing evidence regarding the implication of obesity in the pathogenesis of SCFE, but no definitive mechanism has been proven. The etiology is probably multifactorial, with both mechanical and metabolic factors contributing to the disease, with the later gaining more ground, especially in obese patients. Understanding what causes the disease will help paediatricians and orthopaedists develop more efficient strategies for treating patients and diminishing complication rates.

Relationship between Slip Severity and BMI in Patients with Slipped Capital Femoral Epiphysis Treated with In Situ Screw Fixation

Background: Slipped capital femoral epiphysis (SCFE) is a hip disorder that occurs in adolescence before epiphyseal plate closure, causing anatomical changes in the femoral head. Obesity is known to be the single most important risk factor for idiopathic slipped capital femoral epiphysis (SCFE), which is highly related to mechanical factors. Meanwhile, as increased slip angle increases major complications in patients with SCFE, slip severity is an important factor to evaluate prognosis. In obese patients with SCFE, higher shear stress is loaded on the joint, which increases the likelihood of slip. The study aim was to assess the patients with SCFE treated with in situ screw fixation according to the degree of the obesity and to find any factors affecting the severity of slip. Methods: Overall, 68 patients (74 hips) with SCFE who were treated with in situ fixation screw fixation were included (mean age 11.38, range: 6–16) years. There were 53 males (77.9%) and 15 females (22.1%). Patients were categorized underweight, normal weight, overweight, and obese depending on BMI percentile for age. We determined slip severity of patients using the Southwick angle. The slip severity was defined as mild if the angle difference was less than 30 degrees, moderate if the angle difference was between 30 and 50 degrees, and severe if the angle difference was greater than 50 degrees. To examine the effects of several variables on slip severity, we used a univariable and multivariate regression analysis. The following data were analyzed: age at surgery, sex, BMI, symptom duration before diagnosis (acute, chronic, and acute on chronic), stability, and ability to ambulate at the time of the hospital visit. Results: The mean BMI was 25.18 (range: 14.7–33.4) kg/m2. There were more patients with overweight and obese than those with normal weight in SCFE (81.1% vs. 18.9%). We did not find significant differences between overall slip severity and degree of obesity or in any subgroup analysis. Conclusions: We did not find a relationship between slip severity and degree of obesity. A prospective study related to the mechanical factors affecting the slip severity according to the degree of obesity is needed.

Is the level of vitamin D deficiency correlated with the severity and bilaterality in slipped capital femoral epiphysis? A case series study

The aim of the study is to find the correlation between vitamin D level and the severity of slippage and bilateral development in slipped capital femoral epiphysis (SCFE) cases if any. Thirty-nine patients with moderate-severe stable SCFE were evaluated regarding their vitamin D level and to which extent the severity of vitamin D deficiency, if present, can be correlated with the severity and bilaterality of the slip. Vitamin D serum level was assessed pre- operatively for all patients. In case of deficiency, the patient underwent in situ pinning unless performed before his/her presentation. Alongside, he/she received a vitamin D course until correction prior to the definitive surgery (Imhäuser osteotomy with osteochondroplasty) 6-12 weeks after. Thereafter, osteotomy healing and physis closure were monitored radiologically. Results show that all patients but one had vitamin D deficiency, with an average of 14.39 ng/mL, necessitating vitamin D therapy before proceeding to the definitive surgery. No correlation existed between vitamin D level and Southwick angle severity with a p-value of 0.85. A negative correlation existed between vitamin D level and bilaterality, but not statistically significant (p-value 0.192). Patients’ osteotomy healing was uneventful, and physeal closure was achieved in all the cases that had in situ pinning. We conclude that the severity of Vitamin D deficiency could be linked to the bilateral development of SCFE but not the severity of slippage. Treatment of Vitamin D deficiency facilitates physeal closure.

Prophylactic fixation of the unaffected contralateral side in children with slipped capital femoral epiphysis seems favorable: A systematic review

BACKGROUND

Slipped capital femoral epiphysis (SCFE) occurs in adolescents and has an incidence of around 10 per 100000 children. Children presenting with a unilateral SCFE are 2335 times more likely to develop a contralateral SCFE than the general population. Prognostic factors that have been suggested to increase the risk of contralateral slip include a younger patient, an underlying endocrine disorder, growth hormone use and a higher radiographic posterior sloping angle. However, there is still much debate on the advantages and disadvantages of prophylactic fixation of the unaffected side in an otherwise healthy patient.

AIM

To investigate the risk rate of contralateral SCFE and assess the (dis)advantages of prophylactic fixation of the contralateral hip.

METHODS

A systematic literature search was performed in the Embase, Medline, Web of Science Core Collection and Cochrane databases. Search terms included ‘slipped capital femoral epiphysis,’ ‘fixation,’ ‘contralateral,’ and derivatives. The eligibility of the acquired articles was independently assessed by the authors and additional relevant articles were included through cross-referencing. Publications were considered eligible for inclusion if they presented data about otherwise healthy children with primarily unilateral SCFE and the outcomes of prophylactically pinning their unaffected side, or about the rates of contralateral slips and complications thereof. The study quality of the included articles was assessed independently by the authors by means of the methodological index for non-randomized studies criteria.

RESULTS

Of 293 identified unique publications, we included 26 studies with a total of 12897 patients. 1762 patients (14%) developed a subsequent symptomatic contralateral slip. In addition, 38% of patients developed a subsequent slip on the contralateral side without experiencing clinical symptoms. The most outspoken advantage of prophylactic fixation of the contralateral hip in the literature is prevention of an (asymptomatic) slip, thus reducing the increased risk of avascular necrosis (AVN), cam morphology and osteoarthritis. Disadvantages include an increased risk of infection, AVN, peri-implant fractures, loss of fixation as well as migration of hardware and morphologic changes as a consequence of growth guidance. These risks, however, appeared to only occur incidentally and were usually mild compared to the risks involved with an actual SCFE.

CONCLUSION

The advantages of prophylactic pinning of the unaffected side in otherwise healthy patients with unilateral SCFE seem to outweigh the disadvantages. The final decision for treatment remains to be patient-tailored.

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.

ETIOLOGY, PATHOGENESIS, DIAGNOSIS AND PRINCIPLES OF TREATMENT OF SLIPPED CAPITAL FEMORAL EPIPHYSIS. LITERATURE REVIEW

Aim: to describe the epidemiology, possible causes and predisposing factors for the development of slipped capital femoral epiphysis. To follow the evo­lution of classifications. Analyze indications for surgical treatment, as well as types of surgical treatment.  

Materials and methods: this review article analyzes the data of Russian and foreign literature on the etiology, pathogenesis, diagnosis and treatment of slipped capital femoral epiphysis.  

Results: in view of the frequent distribution in the population, high risks of disability in pediatric patients, the issue of treatment of slipped capital femoral epiphysis remains very relevant. Many methods of surgical treatment have been proposed depending on the stage of the disease, however, they have their own advantages and disadvantages.  

Conclusions: Conservative treatment in the long term did not show good results, generally accepted, according to most sources of literature, surgical treatment is considered. The gold standard in the surgical treatment of the disease does not exist today, and the methods and tactics of treatment are being improved.

Slipped Capital Femoral Epiphysis Associated with Endocrinopathy: A Narrative Review

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Slipped capital femoral epiphysis (SCFE) has a well-documented association with underlying endocrine conditions, including thyroid hormone aberrations and parathyroid dysfunction.

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Recombinant growth hormone therapy has also been identified as a risk factor for the development of SCFE.

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Presentation before their 10th birthday or after their 16th birthday along with height of <10th percentile are reliable risk factors for identifying children with an SCFE who are at a heightened risk for an underlying endocrinopathy and can been used to guide selective laboratory testing.

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Patients with unilateral SCFE presentations with an underlying endocrinopathy are at a heightened risk for contralateral slip development and should be treated with prophylactic fixation.

Medium-term outcomes of extraarticular corrective osteotomy for slipped capital femoral epiphysis

Despite the diversity of surgical options for slipped capital femoral epiphysis (SCFE), there is an ongoing search for the technique that would ensure a satisfactory outcome, stable fixation of bone fragments and a low rate of complications. The aim of this study was to improve the surgical technique for SCFE in patients with moderate and severe SCFE. The study included 52 children (16 girls and 36 boys) aged 10-15 years (the mean age was 13.2 years) with chronic severe (Krechmar’s stage III) stable (according to Loder’s classification) SCFE. The control group (n = 16) underwent a classic Imhauser procedure; the main group (n = 36) underwent a triplane osteotomy proposed by the authors of the study. The patients were examined prior to surgery and in the late follow-up period (the mean follow-up time was 4.7 years, ranging from 1 to 10 years). The procedure included a clinical examination, history taking, radiography to measure the slip angle and the severity of the slip, and the Harris hip score to assess hip function. After 4.7 years, both groups demonstrated an increase in the range of motion, in comparison with their preoperative results (p ≤ 0.05), good Harris hip scores (94 points in the main group and 81 points in the control group. Postoperative radiographs showed consolidation of the bone, recovery of the proximal femur anatomy. Leg length discrepancy improved significantly in both groups. The proposed technique for extraarticular osteotomy allows recovering the length of the affected leg, the anatomy and physiology of the hip joint, is simple and less traumatic.

Is a Femoro-Acetabular Impingement Type Cam Predictable after Slipped Capital Femoral Epiphysis?

(1) Background: Previous studies have proven a high incidence of a femoro-acetabular impingement (FAI) type cam in patients sustaining a slipped capital femoral epiphysis (SCFE). Thus, the current study analyzed, if a cam deformity is predictable after SCFE treatment; (2) Methods: 113 cases of SCFE were treated between 1 January 2005 and 31 December 2017. The radiological assessment included the slip angle after surgery (referenced to the femoral neck (epiphyseal tilt) and shaft axis as Southwick angle) and the last available lateral center edge angle (LCEA), the acetabular- and alpha angle. A correlation was performed between these parameters and the last alpha angle to predict a FAI type cam; (3) Results: After a mean follow-up of 4.3 years (±1.9; 2.0-11.2), 48.5% of the patients showed a FAI type cam and 43.2% a dysplasia on the affected side. The correlation between the epiphyseal tilt and alpha angle was statically significant (p = 0.017) with a medium effect size of 0.28; (4) Conclusions: The postoperative posterior epiphyseal tilt was predictive factor to determine the alpha angle. However, the cut-off value of the slip angle was 16.8° for a later occurrence of a FAI type cam indicating a small range of acceptable deviations from the anatomical position for SCFE reconstruction.

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.

The Genetic Epidemiology of Joint Shape and the Development of Osteoarthritis

Congruent, low-friction relative movement between the articulating elements of a synovial joint is an essential pre-requisite for sustained, efficient, function. Where disorders of joint formation or maintenance exist, mechanical overloading and osteoarthritis (OA) follow. The heritable component of OA accounts for ~ 50% of susceptible risk. Although almost 100 genetic risk loci for OA have now been identified, and the epidemiological relationship between joint development, joint shape and osteoarthritis is well established, we still have only a limited understanding of the contribution that genetic variation makes to joint shape and how this modulates OA risk. In this article, a brief overview of synovial joint development and its genetic regulation is followed by a review of current knowledge on the genetic epidemiology of established joint shape disorders and common shape variation. A summary of current genetic epidemiology of OA is also given, together with current evidence on the genetic overlap between shape variation and OA. Finally, the established genetic risk loci for both joint shape and osteoarthritis are discussed.

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

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

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

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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.

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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.

Which anatomical conditions are associated with limitations of the hip function after SCFE?

Background

Patients sustained a slipped capital femoral epiphysis (SCFE) might have symptoms beyond their stabilization surgery in the childhood.

Methods

35 patients with a SCFE were treated in our clinic and available for a clinical follow-up. The results were compared in dependence of the presence of dysplasia, acetabular retroversion or a FAI type CAM.

Results

A FAI type CAM led to significant inferior results (p < 0.05), especially in combination with a retroversion.

Conclusions

The clinical outcome seemed to be influenced by the presence of a FAI type CAM or a combination with a retroversion, which might aggravate the femoro-acetabular conflict.

Level of evidence

III, retrospective.

Long-Term Safety of Growth Hormone Treatment in Childhood: Two Large Observational Studies: NordiNet IOS and ANSWER

CONTEXT

Growth hormone (GH) treatment has a generally good safety profile; however, concerns about increased mortality risk in adulthood have been raised.

OBJECTIVE

This work aims to assess the long-term safety of GH treatment in clinical practice.

METHODS

Data were collected from 676 clinics participating in 2 multicenter longitudinal observational studies: the NordiNet International Outcome Study (2006-2016, Europe) and ANSWER Program (2002-2016, USA). Pediatric patients treated with GH were classified into 3 risk groups based on diagnosis. Intervention consisted of daily GH treatment, and main outcome measures included incidence rates (events/1000 patient-years) of adverse drug reactions (ADRs), serious adverse events (SAEs), and serious ADRs, and their relationship to GH dose.

RESULTS

The combined studies comprised 37 702 patients (68.4% in low-risk, 27.5% in intermediate-risk, and 4.1% in high-risk groups) and 130 476 patient-years of exposure. The low-risk group included children born small for gestational age (SGA; 20.7%) and non-SGA children (eg, with GH deficiency; 79.3%). Average GH dose up to the first adverse event (AE) decreased with increasing risk category. Patients without AEs received higher average GH doses than patients with more than one AE across all groups. A significant inverse relationship with GH dose was shown for ADR and SAE incidence rates in the low-risk group (P = .003 and P = .001, respectively) and the non-SGA subgroup (both P = .002), and for SAEs in the intermediate- and high-risk groups (P = .002 and P = .05, respectively).

CONCLUSIONS

We observed no indication of increased mortality risk nor AE incidence related to GH dose in any risk group. A short visual summary of our work is available (1).

Subtle Slipped Capital Femoral Epiphysis Is not Associated With Idiopathic Cam Morphology

BACKGROUND

The etiology of idiopathic cam morphology remains unclear. One theory suggests that subtle slipped capital femoral epiphysis (SCFE) leads to proximal femoral changes resulting in cam morphology. The purpose of this study was to evaluate the association between subtle SCFE and cam morphology in a large osteological collection.

METHODS

We examined 962 cadaveric hips to measure 2 markers of cam morphology, alpha angle and anterior femoral head-neck offset (AHNO), and a validated, objective marker of subtle SCFE deformity (calcar ridge line offset). When the femur is viewed medially, the calcar ridge line extends from the lesser trochanter proximally along the postero-inferior femoral neck and points toward the fovea. In SCFE-like deformity, the fovea deviates posteriorly from this projected line. Pearson correlations were performed to evaluate for possible association of calcar ridge line offset with alpha angle and AHNO. In addition, a multiple regression analysis was performed to determine the influence of age, alpha angle, and AHNO on calcar ridge line offset.

RESULTS

There was no clinically relevant association between the calcar ridge line offset and alpha angle (r=-0.02, P=0.58) or AHNO (r=0.08, P=0.012). Furthermore, specimens whose calcar ridge line deviated 1 SD above the mean (more SCFE-like deformity) had a smaller alpha angle (46.6±9.1 vs. 48.3±10.6, P=0.046) and greater AHNO (0.83±0.19 vs. 0.77±0.16, P<0.001), both reflecting less cam-like morphology. On regression analysis, increasing age and increasing AHNO (decreased cam morphology) predicted increased calcar ridge line offset, though the model accounted for only 1.2% of the variance.

CONCLUSIONS

Subtle SCFE-like deformity, as objectively measured from the calcar ridge line, was not predictive of more cam-like morphology, and in fact mild opposite associations were found. Further study is needed to identify other potential etiologies of idiopathic cam morphology.

CLINICAL RELEVANCE

We present evidence from a large, well-documented osteological collection indicating that subtle SCFE is not associated with idiopathic cam morphology.

Association of Slipped Capital Femoral Epiphysis With Panhypopituitarism Due to Pituitary Macroadenoma: A Case Report

Slipped capital femoral epiphysis (SCFE) commonly occurs in overweight or obese adolescents, but can also be associated with endocrine disorders including hypothyroidism, pituitary tumors, and growth hormone deficiency. In this article, we present a case of panhypopituitarism that initially presented with SCFE. A 16-year-old male presented with right SCFE. After a right hip open reduction and percutaneous pinning procedure, findings of skeletal maturity that lagged behind his chronologic age and a delayed Tanner stage resulted in a referral to an endocrine specialist. Endocrine laboratory evaluation identified elevated prolactin levels (1493 ng/mL), hypogonadotropic hypogonadism, and central adrenal insufficiency as evidenced by low morning cortisol level of 1.0 µg/dL. Magnetic resonance imaging revealed a large pituitary T2 isointense mass measuring 1.8 × 2.7 × 2.3 cm. The patient was diagnosed with panhypopituitarism due to a pituitary macroadenoma. Multidisciplinary collaboration for treatment of this patient consisted of oral cabergoline, oral levothyroxine, oral hydrocortisone therapy, intramuscular testosterone therapy, and a prophylactic closed reduction percutaneous pinning of the left hip due to high risk of also developing SCFE of the left hip. Panhypopituitarism should be considered as a diagnosis after atypical presentations of SCFE. In our case, an astute clinical assessment resulted in prompt endocrine referral and management of panhypopituitarism. Our report highlights the importance of multidisciplinary collaborations to guarantee early detection of endocrinopathies in patients with SCFE undergoing surgical interventions in order to avoid potential complications, such as adrenal crisis during surgery.

Slipped Capital Femoral Epiphysis as a Presentation of Underlying Metabolic Disorders: Pseudohypoparathyroidism and Juvenile Hypothyroidism

Slipped capital femoral epiphysis (SCFE) is an abnormality of the proximal femoral physis typically occurring in adolescents and most commonly associated with obesity, although its exact etiology is unknown. In addition to obesity, other associations and predisposing factors proposed in the literature include trauma, vascular injury or compromise, and immunologic, genetic, and metabolic conditions. While not common, metabolic conditions are known to predispose to SCFE and it is essential for radiologists to recognize SCFE as a possible initial presentation of an underlying metabolic disorder. Understanding imaging findings and identification of atypical presentations of SCFE by radiologists can assist clinicians in guiding workup and lead to expedited treatment to prevent worsening outcomes associated with developmental delay.

Hip Injuries in the Adolescent Athlete

This article provides concise and up-to-date information on the most common hip pathologies that affect adolescent athletes. We cover the evaluation and treatment of avulsion injuries, stress fractures, slipped capital femoral epiphysis (SCFE), femoroacetabular impingement, developmental dysplasia of the hip, Legg-Calve-Perthes disease, and coxa saltans focusing on minimizing advanced imaging and using conservative therapy when applicable. Although this is not an all-encompassing list of disorders, it is key to understand these hip pathologies because these injuries occur commonly and can also have detrimental complications if not diagnosed and addressed early, especially SCFE and femoral neck stress fractures.

The Role of Hyperinsulinemia in Slipped Capital Femoral Epiphysis

BACKGROUND

Obesity in the prepuberal stage has been directly associated with slipped capital femoral epiphysis (SCFE). Serum insulin level increases in the prepuberal and adolescence stage, to a greater extent in the obese population. The main objective of this article was to analyze the relationship between insulin levels and SCFE.

METHODS

A case-control study was conducted between January 2018 and April 2019. The study group was formed with patients with SCFE and the control group with patients from the pediatric obesity clinic of our hospital selected during their initial evaluation. None were being treated for obesity. Anthropometric measurements of size, weight, waist circumference, and blood pressure were taken. Body mass index (BMI) and waist-height index of all patients were calculated. According to BMI for age, they were classified as normal, overweight, or obese. Serum determinations of glucose, insulin, glycated hemoglobin, lipid profile, and complete blood count were analyzed. Insulin resistance was diagnosed with Homeostatic Model Assessment (HOMA) >3. Insulin levels >13 U/mL for girls and >17 U/mL for boys were considered as hyperinsulinemia.

RESULTS

We studied 14 patients with SCFE and 23 in the control group. The mean age and BMI in both groups were similar. The elevation of serum insulin was significantly higher in the SCFE group (P=0.001) as was HOMA (P=0.005). Triglycerides and very-low-density lipoprotein were higher in the SCFE group (P=0.037 and 0.009, respectively). Glycemia, glycated hemoglobin, total cholesterol, high-density lipoprotein, low-density lipoprotein, and neutrophils showed no significant difference.

CONCLUSIONS

Patients with SCFE showed elevated levels of insulin, HOMA, triglycerides, and very-low-density lipoprotein, even higher than the control group. Our study demonstrates a significant association between abnormally high serum insulin levels and SCFE. The known effects of insulin on growth cartilage may explain the physeal mechanical insufficiency to support the abnormally high or repetitive loads in accelerated growth stages that lead to SCFE.

LEVEL OF EVIDENCE

Level III-case-control, prognostic study.

SkeletalVis: an exploration and meta-analysis data portal of cross-species skeletal transcriptomics data

MOTIVATION

Skeletal diseases are prevalent in society, but improved molecular understanding is required to formulate new therapeutic strategies. Large and increasing quantities of available skeletal transcriptomics experiments give the potential for mechanistic insight of both fundamental skeletal biology and skeletal disease. However, no current repository provides access to processed, readily interpretable analysis of this data. To address this, we have developed SkeletalVis, an exploration portal for skeletal gene expression experiments.

RESULTS

The SkeletalVis data portal provides an exploration and comparison platform for analysed skeletal transcriptomics data. It currently hosts 287 analysed experiments with 739 perturbation responses with comprehensive downstream analysis. We demonstrate its utility in identifying both known and novel relationships between skeletal expression signatures. SkeletalVis provides users with a platform to explore the wealth of available expression data, develop consensus signatures and the ability to compare gene signatures from new experiments to the analysed data to facilitate meta-analysis.

AVAILABILITY AND IMPLEMENTATION

The SkeletalVis data portal is freely accessible at http://phenome.manchester.ac.uk.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Increased body mass index percentile is associated with decreased epiphyseal tubercle size in asymptomatic children and adolescents with healthy hips

PURPOSE

To investigate whether body mass index (BMI) percentile impacts the morphology of the capital femoral epiphysis in children and adolescents without hip disorders.

METHODS

We assessed 68 subjects with healthy hips who underwent a pelvic CT for evaluation of appendicitis. There were 32 male patients (47%) and the mean age was 11.6 years (sd 2.3). The BMI (k/m²) was calculated for sex- and age-related percentiles according to the Centers for Disease Control and Prevention growth charts. CT images were segmented, and the epiphysis and metaphysis were reformatted using 3D software. We measured the epiphyseal tubercle (height, width and length), the metaphyseal fossa (depth, width and length) and the peripheral cupping of the epiphysis. All measurements were normalized to the diameter of the epiphysis. Pearson's correlation analysis was used to assess the correlations between the variables measured and BMI percentile adjusted for age.

RESULTS

Following adjustment to age, increased BMI correlated to decreased tubercle height (r =-0.34; 95% confidence interval (CI) -0.53 to -0.11; p = 0.005), decreased tubercle length (r = -0.32; 95%CI -0.52 to -0.09; p = 0.008) and decreased tubercle width (r = -0.3; 95% CI -0.5 to -0.07; p = 0.01). There was no correlation between BMI and metaphyseal fossa and epiphyseal cupping measurements.

CONCLUSION

The association between increased BMI percentile and decreased epiphyseal tubercle size, without changes of the metaphyseal fossa and peripheral cupping suggests another morphological change of the femur that may be associated with decreased growth plate resistance to shear stress. Further study is necessary to investigate whether the epiphyseal tubercle size plays a role in the pathogenesis of slipped capital femoral epiphysis in obese children and adolescents.

LEVEL OF EVIDENCE

Level IV.

What Is the Accuracy and Reliability of the Peritubercle Lucency Sign on Radiographs for Early Diagnosis of Slipped Capital Femoral Epiphysis Compared With MRI as the Gold Standard?

BACKGROUND

The diagnosis of slipped capital femoral epiphysis (SCFE) often is delayed. Although lack of clinical suspicion is the main cause of delayed diagnosis, typical radiographic changes may not be present during the initial phases of SCFE. The peritubercle lucency sign for follow-up of the contralateral hip in patients with unilateral SCFE may be beneficial in assisting the early diagnosis. However, the accuracy and reliability of this sign in patients with SCFE is unknown.

QUESTIONS/PURPOSES

(1) What is the accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the peritubercle lucency sign on radiographs for the early diagnosis of SCFE compared with MRI as the gold standard? (2) What are the interobserver and intraobserver reliabilities of the peritubercle lucency sign on radiographs?

METHODS

Between 2000 and 2017, 71 patients underwent MRI for an evaluation of pre-slip or a minimally displaced SCFE. Sixty percent of hips (43 of 71) had confirmed SCFE or pre-slip based on the presence of hip pain and MRI changes, and these patients underwent in situ pinning. Three independent experienced observers reviewed MR images of the 71 hips and agreed on the presence of a juxtaphyseal bright-fluid signal suggesting bone marrow edema in these 43 hips with SCFE, and absence MRI changes in the remaining 28 hips. The same three experienced observers and two inexperienced observers, including a general radiologist and an orthopaedic surgery resident, blindly assessed the radiographs for the presence or absence of the peritubercle lucency sign, without information about the diagnosis. Diagnostic accuracy measures including sensitivity, specificity, PPV, and NPV were evaluated. Intraobserver and interobserver agreements were calculated using kappa statistics.

RESULTS

The overall accuracy of the peritubercle lucency sign on radiographs was 94% (95% CI 91 to 96), sensitivity was 97% (95% CI 95 to 99), specificity was 89% (95% CI 90 to 96), PPV was 93% (95% CI 90 to 96), and NPV was 95% (95% CI 92 to 99). All accuracy parameters were greater than 85% for the five observers, regardless of experience level. Intraobserver agreement was perfect (kappa 1.0), and interobserver agreement was excellent for the peritubercle lucency sign on radiographs across the five observers (kappa 0.81 [95% CI 0.73 to 0.88]). The reliability was excellent for experienced observers (kappa 0.88 [95% CI 0.74 to 1.00]) and substantial for inexperienced observers (kappa 0.70 [95% CI 0.46 to 0.93]), although no difference was found with the numbers available (p = 0.18).

CONCLUSIONS

The peritubercle lucency sign on radiographs is accurate and reliable for the early diagnosis of SCFE compared with MRI as the gold standard. Improving the early diagnosis of SCFE may be possible with increased awareness, high clinical suspicion, and a scrutinized evaluation of radiographs including an assessment of the peritubercle lucency sign.

LEVEL OF EVIDENCE

Level III, diagnostic study.

Predicting subsequent contralateral slipped capital femoral epiphysis: an evidence-based approach

PURPOSE

The purpose of this study was to identify risk factors for developing a subsequent contralateral slipped capital femoral epiphysis (SCFE) and provide a prediction score to quantify risk of subsequent slip at the time of initial presentation.

METHODS

This retrospective study included patients that presented with a unilateral SCFE between 2006 and 2017. Chart and radiographic review were performed to collect demographic, clinical and radiographic risk factors. Descriptive statistics, univariate analyses and multivariate regression analysis were used to compare risk factors between patients that did or did not develop a subsequent contralateral SCFE.

RESULTS

This study included 183 patients and 33 patients (18%) developed a subsequent contralateral SCFE. Younger age at time of initial presentation, lower modified Oxford Score and smaller difference in epiphyseal-diaphyseal angle between both sides during index presentation were significant predictors of subsequent contralateral SCFE. Specifically, age ≤ 11 years, modified Oxford Score ≤ 20 and difference in epiphyseal-diaphyseal angle of ≤ 21° between both hips were predictive of a contralateral slip (Area Under the Curve = 0.78; p < 0.05). The presence of each risk factor increased the risk of subsequent contralateral SCFE and having all three risk factors increased the risk to 73%.

CONCLUSION

There is a significant risk of subsequent contralateral SCFE in patients with unilateral SCFE, and predictive risk factors include younger age, lower modified Oxford Score and smaller difference in epiphyseal-diaphyseal angle between the affected and unaffected hips.

LEVEL OF EVIDENCE

Level III.

Pediatric growth hormone therapy in Greece: analysis of the Hellenic cohort of the GeNeSIS study

PURPOSE

To describe the data from the Greek cohort of the Genetics and Neuroendocrinology of Short Stature International Study (GeNeSIS).

METHODS

GeNeSIS was a prospective, open-label, multinational, observational study collecting information on clinical outcomes and treatment safety of children with growth disorders treated with growth hormone (GH), according to national indications. After informed consent, 305 patients (143 females), including 255 patients with growth hormone deficiency (GHD) and 30 with Turner syndrome (TS), from eight investigational sites, were enrolled in Greece. Demographic data, treatment efficacy, and adverse events were reported at the discretion of attending physicians.

RESULTS

Treatment with GH was undertaken for 247/255 patients with GHD and 29/30 with TS. The majority of patients treated with GHD (73.7%) and TS (84%) with recorded Tanner stage were prepubertal at enrolment. Among patients treated with GHD and TS, 70.45% and 55% were GH-naïve at study entry, respectively. Height standard deviation score (SDS), height velocity SDS, and height SDS-target height SDS numerically improved during the 4-year observation period. The effect of GH treatment was more prominent in the first year of treatment, especially in the GHD group.

CONCLUSIONS

In the Greek cohort of GeNeSIS, GHD is the most frequent indication for GH treatment, followed by TS. While the latter is diagnosed somewhat earlier, GH treatment is not as efficacious as for patients with GHD. No major safety issues were reported during follow-up. The results, which are in accordance with the international literature, should be interpreted in the context of observational studies.

Risk Factors for Readmission After Surgical Treatment of Slipped Capital Femoral Epiphysis

Slipped capital femoral epiphysis (SCFE) is a common, surgically treated adolescent hip condition. This study sought to evaluate postoperative complications and factors associated with hospital readmission using a nationally representative database. The 2013 Healthcare Cost and Utilization Project's Nationwide Readmissions Database was queried to analyze the incidence of acute readmission and complications for all patients with SCFE. Patients were separated based on 3 different operative approaches (open procedures, closed procedures, or both) and were compared based on choice of procedure, clinical characteristics, patient demographics, comorbidities, and complications. Univariate and multivariate techniques were used to predict readmission and complications. A total of 1082 patients with SCFE were identified; 58 (5.9%) were readmitted within 90 days of the index surgery, and 47 (73.4%) underwent a "closed" surgery, including 18 bilateral (27.4%). Increasing age and shorter primary length of stay were protective against readmission. Patients with the comorbidity of hypothyroidism were 47.4 times more likely to be readmitted. Obesity, sex, and median household income were not predictive of readmission. Patients readmitted were more likely to have undergone an index procedure of closed reduction or both an open and closed reduction procedure. This study is the first to report national SCFE readmission and complication rates and allows pediatric orthopedic surgeons to have a better understanding of associated risk factors. [Orthopedics. 2019; 42(6):e507-e513.].

[Slipped capital femoral epiphysis-etiology and pathogenesis]

BACKGROUND

Slipped capital femoral epiphysis (SCFE) is the most significant hip disease in adolescence. Because of its typical occurrence at the time of the pubertal growth spurt and some particular clinical symptoms, it has been a topic of special interest in orthopedic research for a long time. A large number of etiological factors have been described, however their meaning in detail is still controversial.

OBJECTIVES

After a short summary of the structure and function of the epiphysis, an overview of concepts in the pathogenesis of SCFE is given.

MATERIALS AND METHODS

A selective review of literature was performed.

RESULTS

Etiology of SCFE includes genetic, endocrinologic, histochemical and biomechanical factors. During puberty, obesity together with reduced femoral antetorsion are the main risk factors for the disease. The rarer atypical SCFE is closely related to metabolic disorders or other chronical diseases. The pathogenesis is characterized by the disproportion between the load-bearing capacity of the epiphysis and the acting forces on the proximal femur.

CONCLUSIONS

The concept of the multifactorial etiology of SCFE is convincing. The susceptibility of the femoral epiphysis is explained considering the remarkable biomechanic local forces. The initial damage can be shown on the histological and the histochemical level. Important new aspects refer to the leptin-metabolism. However, in the majority of cases, biomechanical factors seem to be more significant than endocrinological phenomena. A complete understanding has not succeeded to date.

[Specific cases of slipped capital femoral epiphysis : Endocrinopathies, hormone therapy and other rare causes]

In slipped capital femoral epiphysis (SCFE) atypical causes can be found in about 5% of cases. The patients' age differs from the typical age of SCFE patients of between age 10 and 16. There are numerous causes of atypical SCFE: different endocrine disorders, sequelae of chronic renal failure and effects of radiation and chemotherapy on the proximal femoral physis. The diagnostic and therapeutic procedures must be expanded to the search for and treatment of endocrinological disorders. Orthopaedic treatment follows the principles applied to patients with idiopathic SCFE. However, the specific treatment modalities which arise from different patient ages and bone qualities are taken into account.

Predicting Risk of Contralateral Slip in Unilateral Slipped Capital Femoral Epiphysis: Posterior Epiphyseal Tilt Increases and Superior Epiphyseal Extension Reduces Risk

BACKGROUND

Femoral morphology may influence the etiology of slipped capital femoral epiphysis (SCFE). We investigated whether radiographic parameters of femoral head-neck morphology are associated with a subsequent contralateral slip in patients presenting with unilateral SCFE.

METHODS

We evaluated 318 patients treated for unilateral SCFE between 2000 and 2017. There were 145 males (46%), and the mean age in the series was 12.4 ± 1.7 years. The patients were followed for a minimum of 18 months or until the development of a contralateral slip (70 patients, 22%). We measured the epiphyseal tilt, epiphyseal extension ratio, alpha angle, and epiphyseal angle of the uninvolved, contralateral hip at initial presentation. Multivariable logistic regression analysis was used to assess whether femoral measurements were associated with the occurrence of a contralateral slip. Receiver operating characteristic (ROC) curves were used to determine optimal thresholds of radiographic measures to determine an increased risk of a contralateral slip. A number-needed-to-treat (NNT) analysis was conducted to evaluate the effectiveness of the femoral measurement thresholds in preventing a contralateral slip.

RESULTS

Multivariable analysis, controlling for triradiate cartilage status, identified the lateral tilt angle and the superior epiphyseal extension ratio as independent factors associated with the likelihood of a contralateral slip. For each additional degree of posterior tilt, the odds of a contralateral slip increase by 8% (odds ratio [OR] = 1.08; 95% confidence interval [CI] = 1.02 to 1.14; p = 0.008), and for each 0.01 increase in the superior epiphyseal extension ratio, the odds of a contralateral slip decrease by 6% (OR = 0.94; 95% CI = 0.88 to 0.99; p = 0.03). A threshold for the epiphyseal tilt of 10° corresponded to a predicted probability of a contralateral slip of 54% in patients with open triradiate cartilage and an NNT of 3.3.

CONCLUSIONS

In patients presenting with unilateral SCFE, a higher posterior tilt of the epiphysis increases the risk while an increased superior extension of the epiphysis reduces the risk of a contralateral slip. Our findings may assist the discussion about contralateral prophylactic pinning in patients with unilateral SCFE.

LEVEL OF EVIDENCE

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

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.

Xanthomatous hypophysitis causing hypogonadotropic hypogonadism resulting in delayed presentation of slipped capital femoral epiphysis

An 18-year-old man who underwent bilateral pinning of his hip joints after a left unstable Slipped Capital Femoral Epiphysis (right pinned prophylactically) was noted to have delayed secondary sexual characteristics and post-operative diabetes insipidus. The patient also described a history of fatigue, headache and polydipsia for the past 4 years. Endocrine investigations revealed reduced androgen levels, hypocortisolism, a borderline normal Serum ACE and secondary hypothyroidism. Magnetic Resonance Imaging of the pituitary gland identified an enhancing mass and a thickened stalk which trans-nasal endoscopic biopsy found to be necrotic with pus. Histology confirmed a diagnosis of Xanthomatous Hypophysitis, an inflammatory condition likely related to a partial rupture of a Rathke cleft cyst. The patient was subsequently commenced on Androgen, Thyroxine, Desmopressin and Hydrocortisone therapy with on-going endocrine follow-up. Although endocrine dysfunction & hypogonadism has been recognised to be a risk factor for SCFE at an atypically older age, due to reduced androgen levels leading to a weakened physeal plate, this is the first known case of a Xanthomatous Hypophysitis resulting in pituitary dysfunction and eventual SCFE. This case highlights that an increased range of pituitary disorders should be considered in late presentations of SCFE; and vice versa the risk of SCFE should be considered in patients with prolonged hypogonadotropic hypogonadism.

Trends in slipped capital femoral epiphysis: is the rate declining?

PURPOSE

Slipped capital femoral epiphysis (SCFE) is an adolescent hip condition with a high risk of complication. The purpose of this study was to evaluate trends in treatment using a prospectively collected paediatric nationally representative database.

METHODS

A total of 9034 patients undergoing treatment for idiopathic SCFE were selected by querying the Healthcare Cost and Utilization Project's Kids' Inpatient Database for the years 1997, 2000, 2003, 2006, 2009 and 2012. The selected patients were separated based on operative approach and these cohorts were analyzed based on temporal and categorical differences in operative approach, patient demographics and clinical characteristics. Univariate and multivariate analyses were used when appropriate and the Mantel-Haenszel test for trend was used in temporal analysis.

RESULTS

Overall SCFE procedures have decreased 27.5% (p < 0.001). Closed procedures have decreased 28.5% (p < 0.001), while open procedures have decreased 44.8% (p < 0.001). Bilateral closed procedures have increased 7.2% (p < 0.001). The ratio of open to closed procedures decreased in patients aged nine to 12 years and increased in patients aged 13 to 16 years (p < 0.001).

CONCLUSION

Here we report age stratified trends in treatment for idiopathic SCFE using nationally representative data and show an overall decrease in admissions and procedures over time.

LEVEL OF EVIDENCE

Level III, retrospective comparison study.

The Epidemiology of Slipped Capital Femoral Epiphysis in American Samoa

The Maori of New Zealand have been identified as a high-risk population for slipped capital femoral epiphysis (SCFE). This study assessed whether the burden of disease from SCFE in the American Territory of American Samoa is similar to that identified in the Maori. This was a retrospective review of children from American Samoa treated for SCFE at a tertiary care pediatric hospital between 2005-2014. Demographic, clinical, and radiographic information was collected. All patients were followed for at least one year after surgery and prophylactically pinned hips were not included. Data for determining incidence was obtained from the United States Census Bureau. Between 2005-2014, 55 American Samoan youth were treated for 73 SCFE. The incidence in the "at-risk" population 5-14 years of age was 53.1 per 100,000. Patients had a mean BMI of 29.5 (19.4-46.4) and mean weight of 76.7 kg (45.9-139 kg). Southwick angle was a mean 40.6°+/- 20.4° (6-83°). Overall, 82.2% of hips were treated with in-situ cannulated screw fixation. At a minimum one-year after initial surgery, 22 hips (30.1%) required major surgery including intertrochanteric osteotomy, osteochondroplasty, or total hip replacement. The incidence of SCFE in American Samoa is extremely high, 53.1 per 100,000 of "at-risk" population 5-14 years old. The mean weight and BMI in SCFE patients from American Samoa is substantially higher than previously published reports. Furthermore, morbidity from SCFE in this population is substantial with 30.1% requiring major surgery either at the time of physeal stabilization or in subsequent years.

Obesity-related metabolic and endocrine disorders diagnosed during postoperative follow-up of slipped capital femoral epiphysis

Background and purpose - Patients with slipped capital femoral epiphysis (SCFE) are phenotypically overweight or obese and may therefore require clinical follow-up of obesity-related disorders. We evaluated obesity-related disorders such as dyslipidemia, type 2 diabetes mellitus (DM), and vitamin-D deficiency during the postoperative period in patients with SCFE. Patients and methods - 51 patients who were operated and followed-up for SCFE and 62 healthy adolescents without SCFE (control group) were included in this retrospective study. Patients' BMI, serum lipid profile (total cholesterol, LDL-C, HDL-C, triglyceride), fasting blood glucose, HbA1c, and serum vitamin D levels were evaluated. Results - At the time of surgery, 45 patients in the SCFE group were overweight or obese (BMI >25). At the latest follow-up, 42 patients in the SCFE group and 53 patients in the control group were overweight/obese. Abnormal serum lipid profile and ratio of total dyslipidemia were similar between the groups. 8 patients had abnormal HbA1c levels in the SCFE group and mean HbA1c levels were significantly higher in the SCFE group (p = 0.03). All patients and controls had low levels of vitamin D. Interpretation - Although serum lipid profile and vitamin D levels were detected as similar in SCFE and control groups, the potential risk of type 2 DM identified via abnormal HbA1c levels was significantly higher in patients with SCFE. We recommend that patients diagnosed with SCFE should be considered as potential candidates for type 2 DM; thus follow-up after surgical treatment should include not only orthopedic outcomes but also evaluation of future risk for DM.

Morphologic Features of the Contralateral Femur in Patients With Unilateral Slipped Capital Femoral Epiphysis Resembles Mild Slip Deformity: A Matched Cohort Study

BACKGROUND

Hip osteoarthritis has been reported in the contralateral hip in patients who had been treated for unilateral slipped capital femoral epiphysis (SCFE) during adolescence. Although this might be related to the presence of a mild deformity, the morphologic features of the contralateral hip in unilateral SCFE remains poorly characterized.

QUESTIONS/PURPOSES

Do measurements of (1) femoral head-neck concavity (α angle and femoral head-neck offset), (2) epiphyseal extension into the metaphysis (epiphyseal extension ratio and epiphyseal angle), and (3) posterior tilt of the epiphysis (epiphyseal tilt angle) differ between the contralateral asymptomatic hips of patients treated for unilateral SCFE and hips of an age- and sex-matched control population without a history of hip disease?

METHODS

From January 2005 to May 2015, 442 patients underwent surgical treatment for SCFE at our institution. Patients were included in this study if they had a pelvic CT scan and unilateral SCFE defined by pain or a limp in one hip without symptoms or obligatory external rotation with flexion in the contralateral hip and no evidence of SCFE findings on available radiographs. Seventy-two (16%) patients had a pelvic CT scan; however, 32 patients with bilateral involvement and one patient with CT imaging of inadequate quality for multiplanar reformatting were excluded. Thirty-nine control subjects were identified from a preexisting database of patients who underwent pelvic CT between January 2008 and January 2014 for assessment of abdominal pain in the setting of suspected appendicitis. Patients in the contralateral asymptomatic hip group then were matched to control subjects using a modified nearest-neighbor approach based on sex and age. Patients in the contralateral asymptomatic hip group were separated in males and females and control subjects were assigned to an appropriate sex category. Then subjects closest in age were matched with each patient. If more than one subject was available as a match for a given patient, the control subject with the closest BMI was selected. The contralateral asymptomatic hip and matched groups had 19 (49%) male patients and 20 (51%) female patients, with mean ages (± SD) of 16 (± 3) years and 16 (± 3) years, respectively (p = 0.16). Matched subjects had a mean BMI of 25 ± 4 kg/m and the mean BMI difference among groups was 5 ± 5 kg/m (p < 0.001). According to the Southwick radiographic criteria nine patients (23%) had a mild slip, 10 (26%) had a moderate slip, and 19 (49%) had severe SCFE. The α angle and femoral head-neck offset, epiphyseal extension ratio and epiphyseal angle, and epiphyseal tilt were assessed in the anterior, anterosuperior, and superior femoral planes on radially reformatted CT by one observer not involved in clinical care of the patients. Inter- and intrarater reliability were determined on 10 randomly selected hips assessed by the same observer and another observer and it was found to be excellent for all femoral measurements (intraclass correlation coefficients > 0.85). Paired t-tests were used to compare the contralateral asymptomatic hip of patients with SCFE and control hips.

RESULTS

The head-neck junction showed decreased concavity in the contralateral femur of patients with unilateral SCFE compared with control subjects as assessed by slightly higher mean α angle in the anterosuperior plane (51° ± 6° versus 48° ± 7°; mean difference, 2°, 95% CI, 0°-5°; p = 0.04) and slightly higher median α angle in the superior plane (45° [range 37°-72°] versus 42° [range, 36°-50°], median shift, 4° [range, 2°-5°], p < 0.001), and slightly lower head-neck offset (anterosuperior: 5 mm ± 2 mm versus 6 mm ± 2 mm, mean difference, -1mm [range, -1 mm to 0 mm], p = 0.009; superior: median, 6 mm [range, 1 mm-8 mm] versus 7 mm [range, 5 mm-9 mm]; median shift, -1 mm [range, -1 mm to 0 mm], p < 0.001). There was less epiphyseal extension in the anterosuperior plane as evidenced by lower epiphyseal extension ratio (72% ± 6% versus 75% ± 6%; p = 0.005) and higher epiphyseal angle (64° ± 7° versus 60° ± 7°; p = 0.003). The epiphysis was slightly more posteriorly tilted (anterior plane tilt: 8° ± 6° versus 5° ± 4°; p = 0.03) and more vertically oriented (superior plane tilt 11° ± 5° versus 14° ± 4°; p = 0.006) in the contralateral asymptomatic hip of patients with SCFE.

CONCLUSIONS

The contralateral femur in patients treated for unilateral SCFE shows decreased concavity of the head-neck junction assessed by a higher α angle and reduced head-neck offset compared with age- and sex-matched control subjects. Because we noted lower epiphyseal extension but a more posteriorly tilted epiphysis, the reduced concavity resembles a mild slip deformity rather than an idiopathic cam morphologic feature.

CLINICAL RELEVANCE

Although we noted a difference in the morphologic features of the head-neck junction between the two groups, the clinical significance is unclear because most differences were rather small. However, our findings suggest that the uninvolved hip in patients with unilateral SCFE may have a subtle asymptomatic cam morphologic feature that may be identified only with advanced imaging (CT or MRI). Future studies should investigate whether these morphologic changes influence development of contralateral SCFE or symptomatic femoroacetabular impingement in the contralateral hip of patients with unilateral SCFE and establish thresholds for indication of prophylactic fixation to avoid further slip and worsening of the morphologic features of the cam-femoroacetabular impingement.

Leptin Elevation as a Risk Factor for Slipped Capital Femoral Epiphysis Independent of Obesity Status

BACKGROUND

Slipped capital femoral epiphysis (SCFE) is strongly associated with childhood obesity, yet the prevalence of obesity is orders of magnitude greater than the prevalence of SCFE. Therefore, it is hypothesized that obesity is not, by itself, a sufficient condition for SCFE, but rather one component of a multifactorial process requiring preexisting physeal pathology. Leptin elevation is seen to varying degrees in patients with obesity, and as leptin has been shown to cause physeal pathology similar to the changes seen in SCFE, we propose that leptin may be a factor distinguishing between patients with SCFE and equally obese children without hip abnormalities.

METHODS

Serum leptin levels were obtained from 40 patients with SCFE and 30 control patients with approximate body mass index (BMI) matching. BMI percentiles were calculated according to Centers for Disease Control and Prevention population data by patient age and sex. Patients were compared by demographic characteristics, leptin levels, odds of leptin elevation, and odds of SCFE.

RESULTS

The odds of developing SCFE was increased by an odds ratio of 4.9 (95% confidence interval [CI], 1.31 to 18.48; p < 0.02) in patients with elevated leptin levels, regardless of obesity status, sex, and race. When grouping patients by their obesity status, non-obese patients with SCFE showed elevated median leptin levels at 5.8 ng/mL compared with non-obese controls at 1.7 ng/mL (p = 0.006). Similarly, obese patients with SCFE showed elevated median leptin levels at 17.9 ng/mL compared with equally obese controls at 10.5 ng/mL (p = 0.039). Serum leptin levels increased in association with obesity (p < 0.001), with an increase in leptin of 0.17 ng/mL (95% CI, 0.07 to 0.27 ng/mL) per BMI percentile point.

CONCLUSIONS

To our knowledge, this study is the first to clinically demonstrate an association between elevated serum leptin levels and SCFE, regardless of BMI. This adds to existing literature suggesting that SCFE is a multifactorial process and that leptin levels may have profound physiological effects on the development of various disease states. Despite a strong association with adiposity, leptin levels vary between patients of equal BMI and may be a vital resource in prognostication of future obesity-related comorbidities.

LEVEL OF EVIDENCE

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

Imaging modalities in patients with slipped capital femoral epiphysis

BACKGROUND

Slipped capital femoral epiphysis (SCFE) is a frequent disorder of the adolescent hip, which may lead to avascular necrosis (AVN) of the femoral head, chondrolysis and early osteoarthritis due to the post-slip deformity of the proximal femur. To warrant the best possible outcome for the affected (and contralateral) hip, early diagnosis and proper treatment are needed.

METHODS

A review of the literature was undertaken to identify today's role of available imaging modalities in the management of SCFE.

SUMMARY

This review outlines the relevancy of different imaging modalities such as radiography, ultrasound, CT, MRI and bone scintigraphy in the treatment of SCFE patients. While standard radiography is the first-choice imaging modality for patients with suspected SCFE, ultrasound and advanced imaging modalities may aid in surgical planning, diagnosis of complications such as AVN and treatment follow-up.

Vitamin D Deficiency in Slipped Upper Femoral Epiphysis: Time to Physeal Fusion

BACKGROUND

Slipped upper femoral epiphysis (SUFE) has an incidence of 1 to 7 per 100,000 adolescents in the United Kingdom and its link with obesity is well established. With an increasing number of pediatric orthopaedic patients presenting with vitamin D deficiency, the aim of our study was to establish the prevalence of vitamin D deficiency in SUFE patients presenting to an orthopaedic department in the United Kingdom and whether a low vitamin D level increases the time to proximal femoral physeal fusion after surgical fixation.

METHODS

A total of 27 pediatric patients, with a female to male ratio of 17:10 and a mean age of 11.5 years (SD=1.99), range 8 to 16 years, presented with a SUFE and their vitamin D level was assessed during the study period, June 2007 to July 2012 (inclusive). The majority of these patients (85.2%) were assessed as vitamin D deficient, with a serum 25-(OH)D<52 nmol/L. The time taken for >50% physeal fusion on anteroposterior radiography after surgical fixation reported in the literature is 9.6 months, with no reported vitamin D deficiency or insufficiency.

RESULTS

In our study, the median time to physeal fusion in the vitamin D-deficient and vitamin D-insufficient patients was 25 months (interquartile range, 17 to 43 mo; mean of 29 mo, SD=16.8). A negative correlation was also observed between vitamin D level and the time taken for physeal fusion after surgical fixation.

CONCLUSIONS

We conclude that a high prevalence of vitamin D deficiency has been observed in our SUFE patients. Comparing the time taken for physeal closure of 9.6 months in the literature with vitamin D-deficient patients, this is prolonged. Indeed, a negative correlation has been shown between vitamin D level and time to physeal fusion. This study highlights the need for regular vitamin D status assessment in SUFE patients to allow early implementation of treatment with vitamin D supplementation. The impact of vitamin D screening and supplementation on SUFE outcomes should be investigated further.

Late correction of neck deformity in healed severe slipped capital femoral epiphysis: short-term clinical outcomes

PURPOSE

Contemporary methods for the management of neck deformity following a healed severe slipped capital femoral epiphysis (SCFE) include subcapital neck osteotomy.

METHODS

18 patients with chronic severe SCFE in the oblique plane (mean slip angle = 70°) constituted the study group. 6 patients with an open physis underwent modified Dunn capital realignment and 12 patients with a closed physis underwent surgical dislocation with a corrective neck osteotomy. 10 patients already had an in-situ pinning.

RESULTS

The mean follow-up was 4.5 years (3-6 years). The mean preoperative modified Harris Hip Score (mHHS) and nonarthritic hip score (NAHS) were 24 and 40 respectively, followed by a score of 89 and 92 respectively at the last follow-up (p = 0.0002). Radiologically, all the parameters showed a significant correction. The mean pre- and postoperative values of alpha angle were 79.8 and 34.5 respectively (p = 0.0002); AP slip angle being 36.7 and 14.8 (p = 0.002); lateral slip angle being 54.2 and 13.6 (p = 0.0002); oblique plane slip angle being 70.7 and 20.8 (p = 0.0002) and centre trochanter distance being -6.9 and 1.2 (p = 0.002). The major complications seen were nonunion of the neck osteotomy (n = 1/12) and chondrolysis (n = 1/6) in the modified Dunn's group. The overall complication rate was 11%. There was no statistically significant difference in outcome between the 2 groups clinically and radiologically.

CONCLUSIONS

Femoral neck osteotomy is a potentially rewarding technique to correct severe neck deformities and restoring hip function in the short term.