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

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.

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.

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.

Orthopaedic Diagnoses in the Black Pediatric Population

The Black pediatric population is one that has been historically underserved and continues to have unmet needs. Factors including lack of diversity in orthopaedic studies and in historical standards, such as bone age, may inadvertently lead to inferior care. There are certain conditions in this population for which the practicing orthopaedic surgeon should have a higher degree of suspicion, including slipped capital femoral epiphysis, Blount disease, and postaxial polydactyly. Systemic diseases with higher rates in this population have orthopaedic manifestations, including sickle cell disease, vitamin D deficiency, and obesity. Racial discrepancies in access to prenatal care can have orthopaedic consequences for babies, especially cerebral palsy and myelodysplasia. Racial discrepancy exists in evaluation for nonaccidental trauma. Increased awareness of these issues better prepares practitioners to provide equitable care.

Tactics of Surgical Treatment of Slipped Capital Femoral Epiphysis Associated With Mild Chronic Epiphyseal Displacement

Background. The appearing of data on cam-type FAI in patients with sequelae of slipped capital femoral epiphysis characterized by mild chronic epiphyseal displacement suggests that along with fixation of the proximal femoral epiphysis, modeling of the head-neck transition and restoration of the femoral offsets using arthroscopic techniques should be performed. Meanwhile, it is well known that after epiphyseal fixation, complete remodeling of the epimetaphysis and, consequently, disappearance of the morphological substrate of potential FAI can occur due to the ongoing enchondral and echondral growth. In this regard, the issue of indications for intraarticular interventions in studied patients remains currently open. The aim of the study was to determine the incidence of FAI in the postoperative period in patients with slipped capital femoral epiphysis characterized by mild chronic epiphyseal displacement, and to estimate the requirement of further surgical treatment. Methods. The results of the examination of 32 patients with mild chronic epiphyseal displacement in the typical posterior inferior direction who underwent cannulated epiphyseal screw fixation were analyzed for the severity of epimetaphysis remodeling and the presence of FAI in the postoperative period. Clinical, radiological, magnetic resonance, and statistical methods were used. Results. At the age of 18-19 years, FAI with pain syndrome in everyday life was found in 9 (28.1%) patients 8 of them did not have even partial remodeling of the femoral component of the joint, another 9 (28.1%) patients did not suffer from pain syndrome in everyday life, but had other clinical, radiological and MR signs of cam-type FAI. Complete or almost complete remodeling of the proximal femoral epimetaphysis occurred in 14 (43.8%) patients. Conclusion. In our opinion, therapeutic and diagnostic arthroscopy of the hip joint for the purpose of modeling the head-neck transition at the age of 18-19 years is indicated for more than one quarter (28.1%) of the investigated patients because of the presence of reliable signs of FAI.

The contralateral hip in slipped capital femoral epiphysis: Is there an easy-to-use algorithm to support a decision for prophylactic fixation?

PURPOSE

To identify a specific factor that can support the decision for prophylactic fixation in unilateral slipped capital femoral epiphysis.

METHODS

This retrospective cohort study included a total national population of 379 children diagnosed with slipped capital femoral epiphysis from 2007 to 2013. Regression analysis used information on slip severity, clinical classification of the index hip, age, sex, age-adjusted body mass index, the difference in epiphyseal-diaphyseal angle, and comorbidity to identify any risk factor for the subsequent development of a slip in the contralateral hip. Four observers evaluated the triradiate cartilage following the modified Oxford bone score grade. The occurrence of later development of a contralateral slip in different stage of physeal closure was used to analyze the sensitivity and specificity for this method.

RESULTS

This study's only predictor for a subsequent contralateral slip was chronological age. At age 13 years or older, 1/15 in girls and 3/65 in boys suffered from a slip in the contralateral hip. Thus, when using age <13 years as a test for deciding when to do prophylactic fixation, the sensitivity would be 88% and specificity 51% for preventing contralateral slip. However, the correlation between the four different observers was too low to be considered useful when assessing the triradiate cartilage for skeletal maturity.

CONCLUSION

We would advocate a prophylactic fixation for children <13 years diagnosed with a unilateral slipped capital femoral epiphysis as an easy-to-use algorithm.

LEVEL OF EVIDENCE

level II.

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.

»

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