Outcomes after slipped capital femoral epiphysis: a population-based study with three-year follow-up

Comparing pinning in situ and capital realignment procedures for severe, stable slipped capital femoral epiphysis: a systematic review

In severe, stable slipped capital femoral epiphysis, it is unclear whether pinning in situ (PIS) or capital realignment procedures (CRPs) are superior. Our primary aim was to compare patient-reported outcome measures (PROMs) following each strategy. Secondary aims were to compare rates of femoral head avascular necrosis (AVN) and complications. MEDLINE, Embase and Cochrane databases were searched according to an agreed strategy. Narrative review articles, case reports, letters to the editor and articles not written in English were excluded. The risk of bias was assessed using the Newcastle-Ottawa Scale. Of the 132 citations identified, 127 were excluded following de-duplication and application of the exclusion criteria. Three observational studies comparing PIS with CRP and two case series considering CRP alone were identified. One article was considered fair quality, and four articles were considered poor. In total, 198 hips from five studies were included (66 PIS, 132 CRP). PIS was associated with moderate-good functional outcomes, and CRP with good-high outcomes. Two comparative studies reported significantly better PROMs following CRP. AVN was reported in 1.5% following PIS and 10.6% following CRP. Regarding other complications, chondrolysis occurred in 3.0% following PIS and 2.4% following CRP. Femoroacetabular impingement rates were markedly higher following PIS (60.6% versus 2.3%). Reoperation rates were also greater following PIS (34.5% versus 13.3%). PIS tends to be associated with favourable AVN rates, but CRP with favourable PROMs and complication rates. However, comparisons were drawn from heterogeneous studies lacking long-term follow-up. Further high-quality research is required.

Socioeconomic Deprivation and its Associations With Follow-up Compliance After In Situ Pinning of Slipped Capital Femoral Epiphysis

BACKGROUND

Slipped capital femoral epiphysis (SCFE) is a common cause of hip pain in adolescents and is most often treated by in situ screw fixation. Orthopaedic follow-up is critical after treatment for SCFE due to risks of complications and subsequent contralateral slip. Recent studies have shown that socioeconomic deprivation is associated with decreased fracture care compliance, but no studies have explored this relationship with SCFEs. The study aims to determine the relationship between socioeconomic deprivation and SCFE follow-up care compliance.

METHODS

This study included pediatric patients treated with in situ pinning of SCFE between 2011 and 2019 at a single tertiary-care urban children's hospital. Demographic and clinical information were obtained from electronic medical records. The Area Deprivation Index (ADI) was used to quantify the socioeconomic deprivation of each. Outcome variables included patient age and status of physeal closure at the most recent appointment, in addition to the length of follow-up (mo). Statistical relationships were evaluated using nonparametric bivariate analysis and correlation.

RESULTS

We identified 247 evaluable patients; 57.1% were male, and the median age was 12.4 years. Most slips were stable (95.1%) and treated with isolated unilateral pinning (55.9%). Median length of follow-up was 11.9 months (interquartile range, 4.95 to 23.1) with median patient age at final visit of 13.6 years (interquartile range, 12.4 to 15.1). Only 37.2% of patients were followed until physeal closure. The mean ADI spread in this sample was similar to the national distribution. However, patients in the most deprived quartile were lost to follow-up significantly earlier (median, 6.5 mo) than those in the least deprived quartile (median, 12.5 mo; P <0.001). Throughout the entire cohort, there was a significant, inverse relationship between deprivation and follow-up length ( rs (238) = -0.3; P <0.001), with this relationship most pronounced in the most deprived quartile.

CONCLUSIONS

In this sample, ADI spread was representative of national trends, and the incidence of SCFE was distributed evenly across deprivation quartiles. However, follow-up length does not mirror this relationship; increased socioeconomic deprivation is associated with an earlier loss to follow-up (often well before physeal closure).

LEVEL OF EVIDENCE

Level II-retrospective prognostic study.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

Level IV.

Early Total Hip Arthroplasty is a Cost-Effective Treatment for Severe Radiographic Slipped Capital Femoral Epiphysis Over an Individual's Lifetime

BACKGROUND

Slipped capital femoral epiphysis (SCFE) causes degenerative changes warranting total hip arthroplasty (THA) in approximately 50% of patients by age 60 years. For severe SCFE, a reorienting intertrochanteric osteotomy (ITO) following in situ pinning (ISP) can decrease impingement with hip flexion, but by altering proximal femoral geometry, complicates subsequent conversion THA. We hypothesized that increasing implant survivorship would affect the most cost-effective treatment strategy (ISP followed by ITO [ISP + ITO] with later THA versus ISP alone [ISPa] with earlier THA) over a patient's lifetime.

METHODS

A state-transition Markov model was constructed to analyze the cost-effectiveness of either ISPa or ISP + ITO over a 60-year time horizon for children who have severe, stable SCFE. Transition probabilities associated with implant and native hip survivorship, state utilities, and costs were derived from the literature. Sensitivity analyses assessed the model robustness. Incremental cost-effectiveness ratios (ICERs) were compared to a societal willingness to pay (WTP) of $100,000 per quality-adjusted life year (QALY).

RESULTS

Over a 60-year horizon, ISPa was costlier ($291,836) than ISP + ITO ($75,227) but achieved overall better outcomes (51.4 QALYs ISPa versus 48.7 QALYs ISP + ITO), rendering ISPa cost-effective with an ICER of $80,980/QALY. Implant survivorship and time horizon were sensitive variables.

CONCLUSION

Based upon current implant performance, ISPa with subsequent earlier THA is cost-effective when considering an individual's life expectancy and thereby deserves consideration in patients who have severe SCFE. Without clear level 1 clinical data, our economic model considers a difficult problem, while providing families and clinicians with a framework for understanding treatment options.

LEVEL OF EVIDENCE

Economic and decision analysis, Level III.

A review of slipped capital femoral epiphysis

ABSTRACT

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

Prevalence of Avascular Necrosis Following Surgical Treatments in Unstable Slipped Capital Femoral Epiphysis (SCFE): A Systematic Review and Meta-Analysis

The choice of treatment for unstable and severely displaced slipped capital femoral epiphysis (SCFE) is controversial. This meta-analysis was conducted to determine the prevalence of femoral head avascular necrosis (AVN) following various treatments for unstable SCFE. Various databases were searched to identify articles published until 4 February 2022. A random-effects model was used to examine prevalence as well as risk ratios with confidence intervals (CIs) of 95%. Thirty-three articles were analyzed in this study. The pooled prevalences of AVN in pinning in situ, pinning following intentional closed reduction, pinning following unintentional closed reduction, and open reduction via the Parsch method, subcapital osteotomy and the modified Dunn procedure were 18.5%, 23.0%, 27.6%, 9.9%, 18.6% and 19.9%, respectively. The risk of developing AVN in pinning following intentional closed reduction was found to be 1.62 times higher than pinning in situ; however, this result was not significant. The prevalence of AVN in open reduction was lowest when performed via the Parsch method; however, this finding should be interpreted with caution, since the majority of slips so-treated are of mild and moderate types as compared with the subcapital osteotomy and modified Dunn procedures, which are predominantly used to treat severely displaced slips. As the risk ratio between intentional closed reduction and the modified Dunn method showed no significant difference, we believe that the modified Dunn method has the advantage of meticulously preserving periosteal blood flow to the epiphysis, thus minimizing AVN risk. In comparison with intentional closed reduction, the modified Dunn method is used predominantly in cases of severe slips.

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.

Is there a persistent capital femoral epiphysis growth after screw fixation for slipped capital femoral epiphysis?

Femoral neck screwing during child development is controversial. The objective of this study was to evaluate the residual growth of the capital femoral physis after screw fixation. This retrospective study included children aged younger than 12 years treated for slipped capital femoral epiphysis (SCFE) with a single percutaneous partially threaded cannulated screw. The children were followed up for at least 1 year. Some patients also underwent prophylactic contralateral screwing. Preoperative, immediate postoperative and final follow-up X-rays were evaluated to determine the degree of slippage, pin–joint ratio (PJR), neck–pin ratio (NPR), number of threads crossing the physis, neck–shaft angle (NSA), screw–physis angle and screw position in the physis. We included 17 patients (29 hips: 18 SCFE and 11 prophylactic) with a mean age of 10.1 years (range: 7.1–11.9 years) at the time of surgery. Significant evolution of radiological growth parameters of the proximal femoral physis was noted during a mean follow-up of 2.4 years (range: 1–4.3 years). The mean PJR significantly decreased from 7.3 to 6.0, the mean NPR significantly decreased from 106 to 96 and the mean number of threads beyond the physis decreased from 3.3 to 1.8. The mean NSA decreased by 6.5°, from 139° to 132.5°. Persistent capital femoral epiphysis growth occurs after screw fixation. The NSA significantly decreases over time but remains within the physiological limits.

Level of evidence: IV (case series)

Total hip arthroplasty in patients with slipped capital femoral epiphysis: a systematic analysis of 915 cases

There is limited evidence on the outcomes of Total Hip Arthroplasty (THA) in Slipped Capital Femoral Epiphysis (SCFE) patients. This systematic review aims to evaluate the current literature in terms of survival rate, functional outcomes, complications and types of implants of THA in SCFE patients. Following the established methodology of PRISMA guidelines, PubMed, Cochrane library, ScienceDirect and Ovid MEDLINE were systematically searched from inception to September 2018. The search criteria used were: (“total hip arthroplasty’’ OR ‘’total hip replacement’’ OR “hip arthroplasty’’ OR ‘’hip replacement’’) AND (‘’slipped capital femoral epiphysis’’ OR ‘’slipped upper femoral epiphysis’’ OR ‘’femoral epiphysis’’). Ten studies were finally included in the analysis and were qualitatively appraised using the Newcastle-Ottawa tool. Variables were reported differently between studies. The sample size varied from 12 to 374 THAs. A total of 877 patients undergone 915 THAs. The mean reported follow-up ranged from 4.4 to 15.2 years and the mean patients’ age at the time of THA from 26 to 50 years. Four studies specified the type of implants used, with 62% being uncemented, 24% hybrid (uncemented cup/cemented stem) and 14% cemented. All but three studies reported the mean survival of implants that ranged from 64.9% to 94.8%. A limited number of complications were mentioned. There was a tendency for more favorable functional outcomes in modern studies. Modern THA-studies in SCFE patients showed improvement of survivorship, clinical outcomes and patient satisfaction. Future higher-quality studies are necessary to estimate long-term postoperative outcomes better.

Effect of seasonal variation on the peak presentation of slipped capital femoral epiphysis. A comparison of children in Johannesburg, South Africa and London, UK

Variation exists in the peak presentation of slipped capital femoral epiphysis (SCFE). The objective of this study was to compare two cohorts of children (South Africa and the UK) and explore similarities and differences regarding demographic and epidemiological features, incidence and seasonal variation in peak presentation. Patients presenting with SCFE at one of two hospitals were included in the study. A retrospective cohort was collected from hospital records. The following factors were recorded: duration of symptoms, chronicity, stability, seasonality, severity and prophylactic pinning. A total of 137 patients were included in the study - 70 patients (80 hips) from South Africa and 67 patients (73 hips) from the UK. Both sites recorded more than 50% incidence of a chronic slip. There was higher delay to presentation in the UK compared with South Africa (90 vs 60 days, P = 0.0262). The UK population were more skeletally mature (32.8% open triradiate cartilage) compared with the South Africa population (64.9% open triradiate cartilage). In both populations, the most common season of symptom onset was summer. In the UK, the most common season of symptom presentation was in autumn compared with summer in South Africa. This study found significant differences in the two countries, including a more skeletally mature population in the UK. Both cohorts showed seasonal variation in peak incidence, but there was more seasonal variation in peak incidence in the UK - in the summer for onset of symptoms and autumn months for time of presentation.

[Fixation techniques for slipped capital femoral epiphysis : Principles, surgical techniques, and complications]

The purpose of this review is to present the pros and cons as well as the surgical techniques of conventional implants used for fixation of slipped capital femoral epiphysis (SCFE). Worth mentioning are K‑wires, Hansson pins, transfixing screws, and gliding screws. We searched PubMed for "ECF" and "SCFE" in combination with "in situ fixation," "pin," "wire," "screw," and "nail." We considered Johansson nail, Knowles pin, and Nyström nail to be obsolete and of historical interest only. We noticed a trend from absolute stability towards some form of dynamic fixation over time, likely related to considerations of growth disturbance of the proximal femur and also the inherent potential for remodeling with time.