Stable Slipped Capital Femoral Epiphysis Research Articles

How Safe and Technical Is Modified Dunn Osteotomy in the Management of Patients with SCFE: A Clinical Trial with Short-Term Follow-Up

Objective. Over the last decade, modified Dunn osteotomy has been widely used in the management of slipped capital femoral epiphysis (SCFE) with varying degrees of complications. Different conclusions have been adopted. Our study represented our experience in using such a technique in stable and unstable SCFE and tried to determine its safety and applicability for routine practice. Methods. Our study adopted an interventional prospective design performed on 24 hips divided evenly between both sexes with a mean age of 13.25. On the Southwick classification, the cases were distributed between moderate and severe, which constituted 41.7% and 58.33%, respectively. Three quarters of the study subjects were stable according to the Loder classification. Each underwent modified Dunn osteotomy after a safe surgical hip dislocation. Results. Over the period of about 1-year follow-up, clinical evaluation was performed by examining the surgical site and assessing the legs’ length, range of hip movement, Harris hip score, and iHOT-12 score. Radiological assessment was performed by calculation of slip angle from the frog lateral view, assessment of union, and occurrence of any complications. The study showed that there was significant improvement in patients in terms of radiological and clinical outcomes, with the occurrence of AVN in 16.7% of cases (4 out of 24). All cases of AVN occurred in unstable hips. Conclusion. Despite the complication of AVN, we believe the results of this study add to the current literature which suggests that modified Dunn osteotomy is an effective and safe technique for the management of moderate and severe SCFE. This trial is registered with PACTR202312819351504.

Temporal trends in surgical implants for in situ fixation of stable slipped capital femoral epiphysis.

Stable slipped capital femoral epiphysis (SCFE) is a pediatric hip disorder managed with in situ fixation of the proximal femoral epiphysis, otherwise known as 'pinning the hip'. The objective of this study was to characterize how the choice of implant for in situ fixation of stable SCFE has changed over time. A systematic review of publications concerning in situ fixation of stable SCFE from January 1993 to November 2021 was conducted. The change in the type, diameter, and number of implants used in publications over time and the age of their respective patient cohorts was evaluated. A total of 207 articles met inclusion criteria. There was an increase in publications using cannulated screws over time (P = 0.0113). As the yearly percentage of publications using threadless non-cannulated implants decreased (P = 0.0309), the percentage using cannulated screws increased (P = 0.0047). Single-implant fixation also increased (P = 0.0409). While there was no difference in the rate of increase of implants < 7 mm or ≥ 7 mm in diameter (P = 0.299), patients with larger-diameter implants were, on average, older than patients with smaller-diameter implants (P = 0.0462). In general, the age of patients undergoing in situ fixation of stable SCFE has not changed (P = 0.595). Irrespective of patient-specific considerations, single cannulated screws have become the implant of choice for in situ fixation of stable SCFE. There has not been a consensus on the optimal implant diameter; instead, patient-specific considerations are of paramount importance in this decision.

Comparing pinning in situ andcapital realignment procedures forsevere, 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.

Idiopathic Slipped Capital Femoral Epiphysis: Demographic Differences and Similarities between Stable, Unstable, and Valgus Types.

Idiopathic slipped capital femoral epiphysis (SCFE) is a known disorder in pre/adolescent children with vague hip/knee pain. We wished to study the demographic differences between stable varus, unstable varus, and valgus idiopathic SCFEs using a retrospective review over a 10-year period of SCFE children seen at a tertiary children's hospital. Standard demographic data was collected, and radiographs were measured to determine the Southwick angle and status of the tri-radiate cartilage. There were 190 patients; 138 had stable varus SCFEs, 45 unstable varus SCFEs, and 7 valgus SCFEs. All unstable SCFEs were varus, and all valgus SCFEs were stable. There were significant differences between the three groups by age at diagnosis, sex, race, SCFE severity, weight percentile, and duration of symptoms. The average age at diagnosis was 11.0 ± 1.2, 11.8 ± 1.8, and 12.3 ± 1.7 years for the valgus, unstable varus, and stable varus groups (p = 0.019), and similarly, SCFE severity was 25° ± 15°, 48° ± 18°, and 35° ± 19° (p = 0.0002) for the three same groups. Patients with valgus SCFEs were mostly female (86%) compared to the stable varus (39.9%) and unstable (47%) groups (p = 0.05) and mostly non-White (86%) (0.011). The duration of symptoms was 4.1 ± 4.1, 2.3 ± 5.0, and 4.5 ± 5.0 months for the valgus, unstable varus, and stable varus groups (p = 0.00005). These three types of idiopathic SCFEs demonstrated differences by age at diagnosis, sex, race, weight percentile, and duration of symptoms.

Hip Impingement of severe SCFE patients after in situ pinning causes decreased flexion and forced external rotation in flexion on 3D-CT.

In situ pinning is an accepted treatment for stable slipped capital femoral epiphysis. However, residual deformity of severe slipped capital femoral epiphysis can cause femoroacetabular impingement and forced external rotation. The aim of this study was to evaluate the (1) hip external rotation and internal rotation in flexion, (2) hip impingement location, and (3) impingement frequency in early flexion in severe slipped capital femoral epiphysis patients after in situ pinning using three-dimensional computed tomography. A retrospective Institutional Review Board-approved study evaluating 22 patients (26 hips) with severe slipped capital femoral epiphysis (slip angle > 60°) using postoperative three-dimensional computed tomography after in situ pinning was performed. Mean age at slipped capital femoral epiphysis diagnosis was 13 ± 2 years (58% male, four patients bilateral, 23% unstable, 85% chronic). Patients were compared to contralateral asymptomatic hips (15 hips) with unilateral slipped capital femoral epiphysis (control group). Pelvic three-dimensional computed tomography after in situ pinning was used to generate three-dimensional models. Specific software was used to determine range of motion and impingement location (equidistant method). And 22 hips (85%) underwent subsequent surgery. (1) Severe slipped capital femoral epiphysis patients had significantly (p < 0.001) decreased hip flexion (43 ± 40°) and internal rotation in 90° of flexion (-16 ± 21°, IRF-90°) compared to control group (122 ± 9° and 36 ± 11°). (2) Femoral impingement in maximal flexion was located anterior to anterior-superior (27% on 3 o'clock and 27% on 1 o'clock) of severe slipped capital femoral epiphysis patients and located anterior to anterior-inferior (38% on 3 o'clock and 35% on 4 o'clock) in IRF-90°. (3) However, 21 hips (81%) had flexion < 90° and 22 hips (85%) had < 10° of IRF-90° due to hip impingement and 21 hips (81%) had forced external rotation in 90° of flexion (< 0° of IRF-90°). After in situ pinning, patient-specific three-dimensional models showed restricted flexion and IRF-90° and forced external rotation in 90° of flexion due to early hip impingement and residual deformity in most of the severe slipped capital femoral epiphysis patients. This could help to plan subsequent hip preservation surgery, such as hip arthroscopy or femoral (derotation) osteotomy.

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

The globally acknowledged treatment for mild to moderate slipped capital femoral epiphysis (SCFE) is single screw in situ fixation, also used for prophylactic contralateral fixation. The Free-Gliding Screw (FG; Pega Medical) is a 2-part free-extending screw system designed to allow the growth of the proximal femur. We aimed to analyze the relationship between skeletal maturity and potential growth of the proximal physis and remodeling of the femoral neck using this implant. Females below 12 years and males below 14 years undergoing in situ fixation for stable SCFE or prophylactic fixation were treated using the implant. Three elements of the modified Oxford Bone (mOB 3 ) score were used to measure maturity (triradiate cartilage, head of the femur, and greater trochanter). Radiographs were analyzed immediately postoperatively and at a minimum of 2 years for a change in screw length, posterior-sloping angle, articulotrochanteric distance, α angle, and head-neck offset. The study group comprised 30 (F:M=12:18) of 39 hips treated with SCFE and 22 (F:M=13:9) of 29 hips managed prophylactically using the free-Gliding screw. In the therapeutic group, chronologic age was a less valuable predictor of future screw lengthening than mOB 3 . An mOB 3 of ≤13 predicted future growth of >6mm but did not reach statistical significance ( P =0.07). Patients with open triradiates showed a mean screw lengthening of 6.6mm compared with those with closed triradiates (4.0mm), but this did not reach significance ( P =0.12). In those with mOB 3 ≤13, the α angle reduced significantly ( P <0.01) and the head-neck offset increased significantly, suggesting remodeling. There was no change in these parameters when mOB 3 ≥14. In the prophylactic group, change in screw length was significant with mOB 3 of ≤13 (mean=8.0mm, P <0.05), as was the presence of an open triradiate cartilage (mean=7.7mm, P <0.05). In both cohorts, posterior-sloping angle and articulotrochanteric distance did not change, indicating no slip progression in either treatment or prophylactic groups and minimal effect on the proximal physeal growth relative to the greater trochanter. Growing screw constructs can halt slip progression while allowing proximal femoral growth in young patients with SCFE. Ongoing growth is better when the implant is used for prophylactic fixation. The results in treated SCFE need to be expanded to demonstrate a clinically meaningful cut-off for significant growth, but SCFE patients with an open triradiate remodel significantly more than those where it is closed. Level III-retrospective comparative study.

Assessment of femoral retroversion on preoperative hip magnetic resonance imaging in patients with slipped capital femoral epiphysis: Theoretical implications for hip impingement risk estimation.

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. 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. 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°). 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.

Slipped capital femoral epiphysis: Diagnostic pitfalls and therapeutic options

One of the most prevalent hip pathologies that develops during adolescence is Slipped Capital Femoral Epiphysis (SCFE), and over the past few decades, its incidence has been rising. To ensure an early diagnosis and prompt intervention, orthopedic surgeons should be aware of this entity. Review of recent developments in clinical examination and imaging diagnostic procedures. The presentation includes commonly used imaging methods, slippage measurement techniques, and classification schemes that are pertinent to treatment. An overview of SCFE surgery based on pertinent study findings and knowledge gained from ongoing clinical practice. The gold standard treatment for stable SCFE cases- those in which the continuity of the metaphysis and epiphysis is preserved-is pinning in situ using a single cannulated screw without reduction. However, there are disagreements over the best course of action for stable moderate/severe SCFE. On the best surgical strategy for unstable epiphysiolysis, no universal agreement has been reached. Finding the surgical procedure that will improve the long-term outcomes of a slipped capital femoral epiphysis is the question at hand.

Screw Thread Configuration Has No Effect on Operative Outcomes of Slipped Capital Femoral Epiphysis

INTRODUCTION The current “gold standard” treatment for slipped capital femoral epiphysis (SCFE) is insertion of a single cannulated screw down the epiphyseal center. Debate remains as to whether partially- (PTCS) or fully-threaded (FTCS) cannulated screws, and what number, are optimal. The present retrospective cohort study compares such constructs in a clinical model. METHODS IRB approval was obtained. Patients (N=158) presenting to a level-one pediatric trauma center for in situ pinning of SCFE between January 2005 and April 2018 were included. Covariates analyzed were sex, race, BMI, history of endocrinopathy, and preoperative designation of unstable SCFE. Outcomes included return to the operating room (OR), avascular necrosis (AVN), hardware failure/removal, and the sequelae of femoroacetabular impingement (FAI). Multivariable logistic regression models included covariates with significant univariate effects, as well as thread configuration, number of screws, preoperative instability, and the screw*thread and screw*instability interactions. RESULTS Average patient age at surgery was 12.3±1.9 years; 63% of patients were male; 68% of patients were White/Caucasian and the remaining 32% were Black/African American. Mean BMI was 28.4±6.4 kg∙m-2. PTCS were utilized in 81.0% of constructs and 1 screw was placed in 83.5% of hips. Outcome rates were as follows: return to OR=15.8%, AVN=7.6%, FAI=7.0%, hardware failure/removal=9.5%. Univariate modeling demonstrated no significant covariate effects on return to OR (each P≥0.181) or AVN (each P≥0.099). Sex had a significant effect on FAI (P=0.012). Age and bilateral SCFE were significantly related to hardware failure/removal (P=0.039 and P=0.015, respectively). Multivariable models found that 2 screw constructs were associated with increased odds of return to OR [P=0.027; OR=3.01 (1.13-7.98)]. Odds of AVN were increased by older age (P=0.024; OR=1.45 [1.03-2.03]) and 2 screw constructs in stable SCFE [screws*stability interaction: P&lt;0.001; OR=60.5 (5.60-652.31)]. Female sex increased odds of FAI (P=0.012; OR=5.17 [1.31-20.36]). Finally, odds of hardware failure/removal were increased by 2 screw constructs [P=0.038; OR=3.64 (1.13-11.70)] and bilateral SCFE [P=0.027; OR=3.51 (1.15-10.74)]. DISCUSSION AND CONCLUSION A single, PTCS comprises the majority of SCFE constructs, and this construct carries the least risk for negative outcomes in cases of stable SCFE. These data demonstrate no significant effects of thread configuration on outcomes. The authors caution orthopaedic surgery providers against using more than one screw in cases of stable SCFE, as well as to monitor older, female, and/or bilateral SCFE patients more closely due to an increased risk for complications.

Prospective evaluation of in situ screw fixation for stable slipped capital femoral epiphysis.

Purpose:We aimed to determine which variables were associated with persistent symptoms or need for further surgery in patients treated with in situ fixation for stable slipped capital femoral epiphysis. We hypothesized that patients with greater proximal femoral deformity would require revision surgical intervention.Methods:We prospectively collected data on stable slipped capital femoral epiphysis patients who underwent in situ screw fixation at a single institution. Demographic and radiographic information, as well as patient-reported outcomes, were collected.Results:Forty-six patients (54 hips) with an average follow-up of 3.5 years (range: 2.0–8.5) and mean pre-op Southwick slip angle of 40.5° ± 19.4° were studied. We observed one complication following the index procedure (2%). Twelve hips (22%) went on to have a secondary procedure 2.7 ± 2.2 years after the index surgery. Severe slips were 14.8× more likely to undergo a secondary procedure than mild and moderate slips (p < 0.001). We found no correlation between slip severity and patient-reported outcomes (p > 0.6). Hips requiring a secondary procedure had significantly lower Hip disability and Osteoarthritis Outcome scores (76.8 ± 18.4) at final follow-up compared to hips that did not require additional surgery (86.8 ± 15.7) (p = 0.042).Conclusion:With minimum 2-year follow-up, 22% of patients required a secondary surgery. Patient-reported outcomes did not correlate with slip severity, but were found to be significantly higher in slipped capital femoral epiphysis patients that did not require a secondary procedure. Prophylactic treatment of all slip-related cam deformity was not found to be necessary in this prospective cohort. Patients with moderate-to-severe slips may require secondary surgery.Level of Evidence:Level II

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.

Factors Affecting Slip Progression After In Situ Screw Fixation of Stable Slipped Capital Femoral Epiphysis.

Slip progression after in situ fixation of slipped capital femoral epiphysis (SCFE) has been reported as occurring in up to 20% of patients. We review SCFE treated with in situ single screw fixation performed at 2 hospitals over a 15-year period to determine the factors associated with slip progression. This case-control study reviews SCFE treated with in situ single cannulated screw fixation with minimum follow up of 1 year and full closure of the affected physis. Slip progression (failure) was defined as worsening of the Southwick slip angle of 10 or more degrees or revision surgery for symptomatic slip progression. Univariate and multivariate analyses were performed comparing success and failure groups for patient characteristics, screw type and position, and radiographic measurements. Ninety three patients with 108 slips met all criteria, with 15 hips (14%) classified as having slip progression (failure). All failures had 3 threads or fewer across the physis. Five hips had 2 threads across the physis, and 4 of the 5 were classified as failures. Lower modified Oxford bone scores were found in the failure group, though the difference was small (0.9, P=0.013). Failure was also associated with partially threaded screws (P=0.001). Failed hips were associated with lower initial Southwick angles (32.8 degrees) than successful hips (40.4 degrees) (P=0.047). In the stepwise model for multivariate regression, 4 factors were identified as significant, with lower initial number of threads (P<0.0001), mild initial Southwick category (P=0.0050), male sex (P=0.0061), and partially threaded screw type (P=0.0116) predicting failure. This study is the largest to date evaluating risk factors for slip progression after SCFE fixation, and the first to consider revision surgery for symptomatic slip progression. For stable SCFE, we demonstrate that 4 threads across the physis with a fully threaded screw of 6.5 mm diameter or greater was sufficient to avoid slip progression. We provide a risk stratification for progression of slip showing that in some cases 3 threads across the physis may be sufficient. Level III-case-control study.

Do Patient Demographics and Socioeconomic Status Influence Severity and Time to Diagnosis in Children With Stable Slipped Capital Femoral Epiphysis?

The time to diagnosis in stable slipped capital femoral epiphysis (SCFE) is often several months because of nebulous history, symptoms of knee/thigh pain, and Medicaid insurance. This study examined the impact of socioeconomic status and demographics on the time to diagnosis and SCFE severity in Indiana children. A retrospective review of all patients at a tertiary children's hospital with SCFE from January 2010 through March 2021 was performed. Standard demographic data and type of insurance was collected. Neighborhood Atlas Mapping was used to determine the state decile of the area deprivation index (ADI), a measure of socioeconomic status using 17 variables related to income, employment, education, and housing. Statistical analyses consisted of standard univariate and bivariate analyses; logistic regression analysis was used to determine predictors of a mild SCFE. A P<0.05 was considered statistically significant. There were 142 patients; 81 male and 61 female. The average age was 12.2±1.7 years, lateral epiphyseal shaft angle of 35±19 degrees, and symptom duration of 4.5±5.0 months. There was no correlation between ADI state deciles and lateral epiphyseal shaft angle (r2=0.008) or symptom duration (r2=0.019). Insurance status and race differed by ADI deciles. In the first decile (least disadvantaged), 44% had government insurance and 89% were White; in the 10th decile (most disadvantaged), 95% had government insurance and 38% were White. Predictors of a mild SCFE were female sex [odds ratio (OR): 3.2 [1.5, 7.0]; P=0.004], symptom duration <3 months [OR: 5.3 (2.4, 11.7); P=0.00004], and White race [OR: 2.4 (1.3, 6.2); P=0.01]. Insurance status and ADI were not significant. Contrary to other studies, neither insurance or socioeconomic status were associated with a delay in diagnosis or SCFE severity. The symptom duration in children with SCFE does not appear to be decreasing over the last several decades. Further investigation is required as to why. Level III-retrospective comparative study.

Среднесрочные результаты внесуставной корригирующей остеотомии бедра при юношеском эпифизеолизе головки бедренной кости

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.

The modified Dunn procedure can be performed safely in stable slipped capital femoral epiphysis but does not alter avascular necrosis rates in unstable cases: a large single-centre cohort study.

Purpose:The modified Dunn procedure for slipped capital femoral epiphysis (SCFE) remains controversial. We reviewed our series over ten years to report our learning curve, experience with intraoperative monitoring of femoral head perfusion and its correlation with postoperative Single-photon emission computed tomography (SPECT-CT) bone scan and femoral head collapse in stable and unstable SCFE.Methods:We retrospectively assessed 217 consecutive modified Dunn procedures performed between 2008 and 2018. In all, 178 had a minimum of one-year follow-up (mean 2.7 years (1 to 9.2)) including 107 stable and 71 unstable SCFE. Postoperative viability was assessed with a three-phase Tc99 bone scan and SPECT-CT. From 2011, femoral head perfusion monitoring was performed intraoperatively using a Codman Intracranial Pressure transducer and the capsulotomy was modified.Results:With intraoperative monitoring, the rate of non-viable femoral heads in stable SCFE decreased from 21.1% to 0% (p < 0.001). In unstable SCFE, the rate remained unchanged from 35.7% to 29.8% (p = 0.669). The positive predictive value (PPV) of pulsatile monitoring for no collapse was 100% in stable and 89.1% in unstable SCFE. Pulsatile monitoring and viable SPECT-CT bone scan gave a 100% PPV for all cases. A non-viable scan defines those hips at risk of collapse since 100% of stable and 68.2% of unstable hips with non-viable bone scans went on to collapse.Conclusion:Our protocol enables safe performance of this complex procedure in stable SCFE with intraoperative monitoring being a reliable asset. The avascular necrosis rate for unstable SCFE remained unchanged and further research into its best management is required.Level of evidence:Level III

PROSPECTIVE EVALUATION OF IN SITU SCREW FIXATION FOR STABLE SLIPPED CAPITAL FEMORAL EPIPHYSIS

Background:In situ screw fixation is the standard of care for the treatment of stable slipped capital femoral epiphysis (SCFE), however, recent studies recommend treatment of all slip-related cam deformity to prevent degenerative changes due to femoroacetabular impingement (FAI).Hypothesis/Purpose:The purpose of this study was to prospectively evaluate radiographic and patient reported outcomes after in situ screw fixation for stable SCFE with minimum 2-year follow-up.Methods:After obtaining IRB approval, we prospectively collected data on all consecutive stable SCFE patients who underwent in situ screw fixation at a single institution. Demographic information, Southwick slip angle (SSA) and alpha angle were recorded. The Hip disability and Osteoarthritis Outcome Score (HOOS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were collected. Basic descriptive statistics, the Mann-Whitney test, and correlation analysis was performed.Results:Forty-four hips in 38 patients with an average pre-op SSA of 41.1±20.0˚ were studied. Cohort characteristics can be found in Table 1. We observed no surgical complications of the index procedure and no cases of avascular necrosis (AVN). Twelve hips (27%) went on to have a secondary procedure (SSA range: 34˚ to 101˚) on average 2.6±2.4 years after the index surgery. These were performed to correct residual deformity, limited hip range of motion, or symptomatic impingement; one patient (2 hips) was referred for total hip arthroplasty due to significant degenerative osteoarthritis at 7.8 years follow-up. There were five complications of the secondary procedures (three implant failures and two mal-positioned implants). Our mean post-op HOOS and WOMAC scores were 84.2±16.8 and 87.8±13.9, respectively. Severe slips were 19.3 times more likely to undergo a secondary procedure than mild and moderate slips (p<0.001), however we found no correlation between slip severity and patient reported outcomes (p>0.6).Conclusion:With minimum 2-year follow-up, 27% of patients went on to require a secondary surgery after in situ screw fixation for stable SCFE. Patient reported outcomes did not correlate with slip severity (p>0.6) but were found to be significantly higher in SCFE patients that did not require a secondary procedure (p=0.023). Prophylactic treatment of all slip-related cam deformity was not found to be necessary in this prospective cohort. While in situ screw fixation can be used to safely treat mild to moderate stable slips, patients with moderate to severe stable slips may require secondary surgery and have a higher complication rate with worse patient reported outcomes.Level 2

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.

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

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. 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. 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. 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 IV-retrospective study.

Modified Dunn procedure versus percutaneous pinning in moderate/severe stable slipped capital femoral epiphyses.

The modified Dunn procedure (MDP) has risen enthusiasm in treating slipped capital femoral epiphyses (SCFE) due to the anatomic reduction and high patients' satisfaction rates at long-term follow-up. Main aim of this study is to compare clinical and radiographic outcomes of 2 cohorts with moderate to severe stable SCFE treated by MDP and in situ fixation. Medical records were analysed to collect demographic data, comorbidities and time from slip to surgery. The collected postoperative data were: avascular necrosis (AVN); complications; progression of osteoarthritis and subsequent procedures. Southwick angles (SA), alpha angles and Klein line were measured on the preoperative x-rays, on the immediate postoperative period and at the latest follow-up. Outcomes scores were recorded by the following questionnaires: the Harris Hip Score, the Hip disability and Osteoarthritis Outcome Score, the Merle d'Aubigné and Postel score and the Western Ontario and McMaster Universities Arthritis Index. Kaplan-Meier survivorship curve was calculated. We compared 81 hips treated by MDP with 22 hips treated by in situ pinning (PS) for moderate/severe stable SCFE. No significant differences were found between the 2 groups in terms of age, BMI, comorbidities and preoperative slip angles. At the latest follow-up, postoperative anteroposterior mean slip angles were respectively 6.2 and 19.9° in MDP and PS group (p = 0.3). Slip angles in frog lateral view were 11° in the MDP group and 39.7° in the PS group (p = 0.2). MDP group achieved better correction angles on frog leg view (11° vs. 39.7°; p < 0.001). There was no statistically significant difference in the occurrence of AVN among both groups (19.7% MDP group vs. 31.8% PS group) (p = 0.2). The MDP in treating severe stable SCFE showed the best deformities corrections in conjunction with the highest functional scores at long-term follow-up and similar rates of osteonecrosis compared to in situ fixation.

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

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