UNASSIGNED: The role of prophylactic pinning of the contralateral hip in unilateral SCFE is well established in patients with risk factors for developing contralateral slip. The effect of prophylactic pinning on the growth and morphology of the hip is not well documented in the literature. We aimed to study the effect of prophylactic pinning on the residual growth and morphology of the proximal femur.
UNASSIGNED: The institutional database was searched for all unilateral SCFE cases for the period 2011 to 2020. A total of 171 unilateral SCFE cases were identified. All the radiographs were scanned and those patients who had follow-up X-rays till skeletal maturity were included in the study. Prophylactic pinning was performed using 6.5 mm fully threaded cancellous screws in supine position on a radiolucent table. The following radiological parameters were measured on the post-operative X-rays and at skeletal maturity: (i) neck length (NL), (ii) neck-shaft angle (NSA), (iii) femoral offset (FO), (iv) articulo-trochanteric distance (ATD) and (iv) tip-apex distance (TAD) by two different observers.
UNASSIGNED: The mean age of the cohort was 13.7 years. ATD decreased from the mean value of 25.67 mm in post-operative radiographs to 20.84 mm in final follow-up radiographs. The NL, FO, and TAD were found to be increasing with age with mean final follow-up values of 55.35 mm, 41.41 mm, and 6.19 mm respectively compared to post-operative mean values of 50.95 mm, 37.4 mm, and 4.69 mm. There was no significant change in the neck-shaft angle. The mean post-operative NSA was 132.9° and it was 131.8° at final follow-up radiographs.
UNASSIGNED: Prophylactic pinning in unilateral SCFE does not stop the growth of the proximal femur completely. The ATD decreases in all the patients with prophylactic screw fixation probably due to the discrepancy in growth between the trochanteric apophysis and proximal femoral physis. The clinical effects of this subtle change in the morphology of the proximal femur need further investigation.
UNASSIGNED: Level IV Case series.

BACKGROUND: In Sweden, most children with slipped capital femoral epiphysis (SCFE) are operated on with a single smooth pin or a short-threaded screw, allowing further growth of the femoral neck. Using the Swedish Pediatric Orthopaedic Quality registry, SPOQ, we investigated whether angular remodelling occurs adjacent to the proximal femoral epiphysis after fixation of SCFE using implants, allowing continued growth of the femoral neck.
METHODS: During 2008-2010 a total national population of 155 children were reported to the SPOQ registry. Following our strict inclusion criteria, radiographs of 51 hips were further assessed. The lateral Head Shaft Angle (HSA), the Nötzli 3-point α-angle, the anatomic α-angle, and the Anterior Offset Ratio (AOR) on the first postoperative radiographs and at follow-up were measured to describe the occurrence of remodelling. Slip severity was categorised as mild, moderate or severe according to postoperative HSA.
RESULTS: Mean and SD values for the change in HSA were 3,7° (5,0°), for 3-point α-angle 6,8° (8,9°), and anatomic α-angle 13,0° (16,3°). The overall increase in AOR was 0,038 (0.069). There were no significant differences between the slip severity groups.
CONCLUSIONS: We found limited angular remodelling after in situ fixation with smooth pins or short threaded screws for SCFE. The angular remodelling and the reduction of the CAM deformity was less than previously described after fixation of SCFE with similar implants. Results about the same magnitude with non-growth sparing techniques suggest that factors other than longitudinal growth of the femoral neck are important for angular remodelling.

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.

UNASSIGNED: Slipped capital femoral epiphysis is a common pediatric hip disease and was associated with femoral retroversion, but femoral version was rarely measured. Therefore, mean femoral version, mean femoral neck version, and prevalence of femoral retroversion were analyzed for slipped capital femoral epiphysis patients.
UNASSIGNED: A retrospective observational study evaluating preoperative hip magnetic resonance imaging of 27 patients (49 hips) was performed. Twenty-seven untreated slipped capital femoral epiphysis patients (28 slipped capital femoral epiphysis hips and 21 contralateral hips, age 10-16 years) were evaluated (79% stable slipped capital femoral epiphysis, 22 patients; 43% severe slipped capital femoral epiphysis, 12 patients). Femoral version was measured using Murphy method on magnetic resonance imaging (January 2014-December 2021, rapid bilateral 3-dimensional T1 water-only Dixon-based images of pelvis and knee). All slipped capital femoral epiphysis patients underwent surgery after magnetic resonance imaging.
UNASSIGNED: Mean femoral version of slipped capital femoral epiphysis patients (-1° ± 15°) was significantly (p < 0.001) lower compared to contralateral side (15° ± 14°). Femoral version of slipped capital femoral epiphysis patients had significantly (p < 0.001) wider range from -42° to 35° (range 77°) compared to contralateral side (-5° to 44°, range 49°). Mean femoral neck version of slipped capital femoral epiphysis patients (6° ± 15°) was lower compared to contralateral side (11° ± 12°). Fifteen slipped capital femoral epiphysis patients (54%) had absolute femoral retroversion (femoral version < 0°). Six of the 12 hips (50%) with severe slips and 4 of the 8 hips (50%) with mild slips had absolute femoral retroversion (femoral version < 0°). Ten slipped capital femoral epiphysis patients (40%) had absolute femoral neck retroversion (femoral neck version < 0°).
UNASSIGNED: Although slipped capital femoral epiphysis patients showed asymmetrically lower femoral version compared to contralateral side, there was a wide range of femoral version, underlining the importance of patient-specific femoral version analysis on preoperative magnetic resonance imaging. Absolute femoral retroversion was prevalent in half of slipped capital femoral epiphysis patients, in half of severe slipped capital femoral epiphysis patients, and in half of mild slipped capital femoral epiphysis patients. This has implications for anterior hip impingement and for surgical treatment with in situ pinning or femoral osteotomy (e.g. proximal femoral derotation osteotomy) or other hip preservation surgery.

Recent investigations suggest that physeal morphologic features have a major role in the capital femoral epiphysis stability and slipped capital femoral epiphysis (SCFE) pathology, with a smaller epiphyseal tubercle and larger peripheral cupping of the femoral epiphysis being present in hips with progressive SCFE compared to healthy controls. Yet, little is known on the causal versus remodeling nature of these associations. This study aimed to use preoperative magnetic resonance imaging (MRI) of patients with unilateral SCFE to perform a comparison of the morphology of the epiphyseal tubercle, metaphyseal fossa, and peripheral cupping in hips with SCFE versus the contralateral uninvolved hips. Preoperative MRIs from 22 unilateral SCFE patients were used to quantify the morphological features of the epiphyseal tubercle (height, width, and length), metaphyseal fossa (depth, width, and length), and peripheral cupping height in three dimension. The quantified anatomical features were compared between hips with SCFE and the contralateral uninvolved side across the whole cohort and within SCFE severity subgroups using paired t-test. We found significantly smaller epiphyseal tubercle heights (p < 0.001) across all severities of SCFE when compared to their uninvolved contralateral side. There was a marginally smaller metaphyseal fossa length (p = 0.05) in SCFE hips compared to their contralateral uninvolved hips, with mild SCFE hips specifically having smaller fossa and epiphyseal lengths (p < 0.05) than their contralateral uninvolved side. There were no side-to-side differences in any other features of the epiphyseal tubercle, metaphyseal fossa and peripheral cupping across all severities (p > 0.05). These findings suggest a potential causal role of epiphyseal tubercle in SCFE pathogenesis.

OBJECTIVE: Fixation techniques used in the treatment of slipped capital femoral epiphysis (SCFE) that allow continued growth of the femoral neck, rather than inducing epiphyseal fusion in situ, have the advantage of allowing remodelling of the deformity. The aims of this study were threefold: to assess whether the Free-Gliding (FG) SCFE screw prevents further slip; to establish whether, in practice, it enables lengthening and gliding; and to determine whether the age of the patient influences the extent of glide.
METHODS: All patients with SCFE who underwent fixation using FG SCFE screws after its introduction at our institution, with minimum three years\' follow-up, were reviewed retrospectively as part of ongoing governance. All pre- and postoperative radiographs were evaluated. The demographics of the patients, the grade of slip, the extent of lengthening of the barrel of the screw and the restoration of Klein\'s line were recorded. Subanalysis was performed according to sex and age.
RESULTS: A total of 19 hips in 13 patients were included. The mean age of the patients at the time of surgery was 11.5 years (9 to 13) and the mean follow-up was 63 months (45 to 83). A total of 13 FG SCFE screws were used for the fixation of mild or moderate SCFE, with six contralateral prophylactic fixations. No hip with SCFE showed a further slip after fixation and there were no complications. Lengthening occurred in 15 hips (79%), with a mean lengthening of the barrel of 6.8 mm (2.5 to 13.6) at final follow-up. Remodelling occurred in all hips with lengthening of the barrel. There was statistically more lengthening in patients who were aged < 12 years, regardless of sex (p = 0.002).
CONCLUSIONS: The FG SCFE screw is effective in preventing further slip in patients with SCFE. Lengthening of the barrel occurred in most hips, and thus allowed remodelling. This was most marked in younger children, regardless of sex. Based on this study, this device should be considered for use in patients with SCFE aged < 12 years instead of standard pinning in situ.Cite this article: Bone Joint J 2023;105-B(2):215-219.

BACKGROUND: Slipped capital femoral epiphysis (SCFE) requires surgical treatment when diagnosed. The surgical management of moderate to severe SCFE remains an area of controversy among pediatric orthopedic surgeons. The severity of slippage, the viability of the femoral epiphysis, and the method of surgical management determine the long-term clinical and radiographical outcome. This study sought to evaluate the mid-term results of subcapital realignment of chronic stable slipped femoral epiphysis with open physis using surgical hip dislocation.
METHODS: This study was a prospective case series of adolescents with moderate or severe degrees of chronic SCFE who had undergone subcapital osteotomy using the surgical hip dislocation technique. The Harris Hip Score (HHS) was used to assess functional outcomes at 6 years of follow-up. A HHS of ≥ 80 points was considered satisfactory. Postoperative radiological outcomes were evaluated using epiphyseal-shaft angles and alpha angles. Postoperative complications were observed.
RESULTS: This study included 40 patients, 32 (80%) males and 8 (20%) females, with a mean age of 14.1 ± 1.8 years. There was a statistically significant improvement in the mean HHS from 45 ± 12.3 preoperatively to 91.8 ± 11.6 points at 6 years of follow-up. The mean epiphyseal-shaft angle reduced from 60.5 ± 15.3° preoperatively to 10.3 ± 2.4° postoperatively, P < 0.001. The mean alpha angle reduced from 72.5 ± 10.1° preoperatively to 40.4 ± 6.4°, P < 0.001. Four (10%) patients showed femoral head avascular necrosis (AVN).
CONCLUSIONS: Subcapital realignment of chronic SCFE can achieve satisfactory clinical and radiological outcomes, but femoral head AVN remains a risk. Level of evidence Level IV.

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.
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).
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.
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.
Economic and decision analysis, Level III.

OBJECTIVE: We sought to determine if the magnitude of anterior physeal separation (APS) in slipped upper femoral epiphysis was a predictor for the subsequent development of avascular necrosis (AVN). Anterior Physeal Separation (APS) is defined as the distance between the anterior lip of the bony capital epiphysis and the lateral corresponding point of the adjacent bony metaphysis on the Lauenstein radiographic view. It represents hinging of the posterior aspect of the metaphysis with the anterior epiphysis lifting away from its adjacent metaphysis, indicating instability and potential vulnerability of the vessels.
METHODS: A retrospective review of all patients treated regionally for slipped upper femoral epiphysis over a 9 year period (2010-2018 inclusive) were identified. Data regarding demographics, radiological parameters and outcomes was recorded. APS was measured on a Launestein radiograph view, with the patient supine, the hip and knee are flexed to 40°, and the hip externally rotated 45°, with film-focus distance of 100 cm. Analysis of the APS was performed to validate a threshold above which AVN occurs.
RESULTS: We identified 147 hips in 142 patients, of which 5 had bilateral slips at the time of presentation. Average anterior physeal separation was 3.8 ± 1.8 mm, with higher grade slips having significantly greater APS values. Increased APS values were seen with Loder \"unstable\" slips. Seven hips (4.8%) developed AVN, and in these cases the APS was significantly larger than those who did not (8.5 ± 1.4 Vs 3.9 ± 1.7; p < 0.001). Receiver operator curve analysis demonstrated a critical value of 7.5 mm was associated with a 100% sensitivity and 98.6% specificity for AVN. We identified some grade II/moderate slips with high APS values had similar outcomes to grade III/severe slips, and therefore suggest that APS may serve to alert the surgeon on counselling patients on the risk of developing AVN and to consider strategies to minimise the risk of AVN.
CONCLUSIONS: APS is sensitive, specific, accurate and reliable for the association with AVN in SUFE. Its values closely reflect the high AVN rates seen in acute and unstable SUFE. This risk is greatest if the magnitude of APS exceeds the critical value of 7.5 mm.

Slipped Capital Femoral Epiphysis (SCFE) is a physeal disorder of the proximal femur. Misdiagnosis and late treatment are associated with poorer outcomes. The epidemiology and delays in treatment of the disease between 1968 and 2018 were investigated in North Trinidad. The number of cases presenting annually has increased over the decades and the incidence between 2008-2018 was 2.2 cases per 100 000 per year. Almost 70% of cases were above the 95th percentile for body weight. Delay in treatment from onset of symptoms was 278 ± 258 days. Awareness of the risk factors and clinical presentation of SCFE may facilitate early diagnosis and treatment, and prevent severe hip disability in adulthood.