Aims

This study analysed the clinical and radiological outcome of anatomical reduction of a moderate or severe stable slipped capital femoral epiphysis (SCFE) treated by subcapital osteotomy (a modified Dunn osteotomy) through the surgical approach described by Ganz.

Aims. 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). Conclusion. 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

Aims. The aim of this study was to inform the epidemiology and treatment of slipped capital femoral epiphysis (SCFE). Methods. This was an anonymized comprehensive cohort study, with a nested consented cohort, following the the Idea, Development, Exploration, Assessment, Long-term study (IDEAL) framework. A total of 143 of 144 hospitals treating SCFE in Great Britain participated over an 18-month period. Patients were cross-checked against national administrative data and potential missing patients were identified. Clinician-reported outcomes were collected until two years. Patient-reported outcome measures (PROMs) were collected for a subset of participants. Results. A total of 486 children (513 hips) were newly affected, with a median of two patients (interquartile range 0 to 4) per hospital. The annual incidence was 3.34 (95% confidence interval (CI) 3.01 to 3.67) per 100,000 six- to 18-year-olds. Time to diagnosis in stable disease was increased in severe deformity. There was considerable variation in surgical strategy among those unable to walk at diagnosis (66 urgent surgery vs 43 surgery after interval delay), those with severe radiological deformity (34 fixation with deformity correction vs 36 without correction) and those with unaffected opposite hips (120 prophylactic fixation vs 286 no fixation). Independent risk factors for avascular necrosis (AVN) were the inability of the child to walk at presentation to hospital (adjusted odds ratio (aOR) 4.4 (95% CI 1.7 to 11.4)) and surgical technique of open reduction and internal fixation (aOR 7.5 (95% CI 2.4 to 23.2)). Overall, 33 unaffected untreated opposite hips (11.5%) were treated for SCFE by two-year follow-up. Age was the only independent risk factor for contralateral SCFE, with age under 12.5 years the optimal cut-off to define ‘at risk’. Of hips treated with prophylactic fixation, none had SCFE, though complications included femoral fracture, AVN, and revision surgery. PROMs demonstrated the marked impact on quality of life on the child because of SCFE. Conclusion. The experience of individual hospitals is limited and mechanisms to consolidate learning may enhance care. Diagnostic delays were common and radiological severity worsened with increasing time to diagnosis. There was unexplained variation in treatment, some of which exposes children to significant risks that should be evaluated through randomized controlled trials. Cite this article: Bone Joint J 2022;104-B(4):519–528

Purpose. We share our experience in management of failed in-situ pinning in severe unstable Slipped Capital Femoral Epiphysis (SCFE) by surgical dislocation approach. Method. A retrospective review of hip database from 2006 to 2013 showed 41 children underwent surgical dislocation for SCFE. We identified seven who had severe slip with failed in-situ pinning. Results. The mean age at presentation was 11.9 years (10–14 years). The average interval between in-situ pinning and surgical dislocation was 10 months (2 to 18 months). The mean follow-up was 50.14 months (25 – 66 months). The mean preoperative slip angle in the oblique plane was 76° (61.1° – 121.5°), the mean preoperative alpha angle was 127.3° (93.1° – 145°), and preoperative head neck offset was −12.7mm (0 – −21.2mm). The mean corrections at latest follow-up were oblique plane slip angle 20.6° (4.2° – 41.8°), alpha angle 51.3° (45.3° – 58°), and head-neck offset 9.5mm (1 – 16.2mm). The mean Modified Harris Hip Score (MHHS) preoperatively was 19.57 (0 – 56) and the mean non-arthritic hip score (NAHS) was 21.07 (5 – 51.5). The mean MHHS at the last visit was 88.97 (71 – 96) and NAHS was 84.28 (69.5 – 91). All patients had gross external rotation deformity at presentation; mean internal rotation of 25° ranging from (0 – 40°) was achieved at follow-up. Four patients had avascular necrosis identified on subtraction MRI scan preoperatively. These four underwent second stage hinged distraction of the hip. Mean duration of hinged distraction was 7.6 months. At follow-up 4 had Tonnis 0, one Tonnis 1 and two Tonnis 2 grade of osteoarthritis. Conclusion. The short-term result of our protocol for management of failed in-situ pinning by staged surgical dislocation and hinged distraction has been encouraging. This could potentially prolong the life of native hip to the third decade of life before definitive salvage procedures could be contemplated

Aims. We aimed to assess the cumulative risk of total hip arthroplasty (THA) from in situ fixation for slipped capital femoral epiphysis (SCFE) after a follow-up of almost 50 years. Methods. In this study, 138 patients with 172 affected hips treated with in situ fixation were evaluated retrospectively. A total of 97 patients (70%) were male and the mean age was 13.6 years (SD 2.1); 35 patients (25%) had a bilateral disease. The median follow-up time was 49 years (interquartile range 43 to 55). Basic demographic, stability, and surgical details were obtained from patient records. Preoperative radiographs (slip angle; SA) were measured, and data on THA was gathered from the Finnish National Arthroplasty Register. Results. The preoperative SA was a mean of 39° (SD 19°). At follow-up, 56 of the patients had undergone THA for a hip previously fixed in situ for SCFE (41%) and 64 of all affected hips had been replaced (37%). Kaplan-Meier analysis gave a median prosthesis-free postoperative survival of 55 years (95% confidence interval (CI) 45 to 64) for the affected hips. In a multivariate analysis, female patients had a two-fold risk for THA (hazard ratio (HR) 2.42 (95% CI 1.16 to 5.07)) and a greater preoperative SA increased the risk of THA (HR 1.03 for every increment of 1° (95% CI 1.01 to 1.05)), while patient age at surgery, slip laterality, stability of slip, or diagnostic delay did not have a statistically significant effect on the risk of THA. Conclusion. SCFE treated primarily with in situ fixation may lead to THA in more than 40% of affected hips at a near 50-year follow-up. This risk is approximately 15-times the reported lifetime risk in the Finnish general population. Female sex and increasing preoperative SA significantly predicted higher risk of THA. Cite this article: Bone Joint J 2023;105-B(12):1321–1326

Avascular necrosis is a serious complication of slipped capital femoral epiphysis and is difficult to treat. The reported incidence varies from 3% to 47% of patients. The aims of treatment are to maintain the range of movement of the hip and to prevent collapse of the femoral head. At present there are no clear guidelines for the management of this condition and treatment can be difficult and unrewarding. We have used examination under anaesthesia and dynamic arthrography to investigate avascular necrosis and to determine the appropriate method of treatment. We present 20 consecutive cases of avascular necrosis in patients presenting with slipped capital femoral epiphysis and describe the results of treatment with a mean follow-up of over eight years (71 to 121 months). In patients who were suitable for joint preservation (14), we report a ten-year survivorship of the hip joint of 75% and a mean Harris hip score of 82 (44 to 98)

Slipped capital femoral epiphysis may be associated with hypothyroidism and other endocrinopathies. Routine screening for such abnormalities is unlikely to be cost-effective since the overall incidence of these disorders, in association with slipped capital femoral epiphysis, is low. The identification of a presenting characteristic which would predict the chance of an associated endocrinopathy would allow only selected children to be screened. Our aim was to determine if certain characteristics were useful as a screen for patients with an underlying endocrinopathy who presented with slipped capital femoral epiphysis. Between January 1988 and December 1996 we recorded gender, age, height, unilateral or bilateral involvement and an associated diagnosis of endocrinopathy for all patients who were treated for slipped capital femoral epiphysis. Of 166 such patients 13 (7.8%) had an endocrinopathy. Height was the only useful screening characteristic, although bilateral involvement was more likely in those with an endocrinopathy. Most (90.9%) of this latter group were below the tenth percentile for height compared with only 5.4% in those who did not have an endocrinopathy (p < 0.005). The sensitivity and negative predictive value of detecting an underlying endocrinopathy in a patient presenting with a slipped capital femoral epiphysis and short stature (tenth percentile or less) were 90.2% and 98.6%, respectively. Patients who are on or below the tenth percentile for height at the time of presentation should be screened for a possible endocrine abnormality using measurement of thyroid-stimulating hormone and free thyroxine as a preliminary screening test. These hormones are most likely to be abnormal in the presence of endocrine dysfunction

Fixation by a single screw is considered the current treatment of choice for a slipped capital femoral epiphysis. This approach promotes premature physeal closure. The use of a modified, standard, single, cannulated screw designed to maintain epiphyseal fixation without causing premature closure of the physis was reviewed in ten patients. The nine boys and one girl aged between 10.6 and 12.6 years with unilateral slipped capital femoral epiphysis (SCFE), were markedly skeletally immature (Tanner stage I, bone age 10 to 12.6 years). Clinical and radiological review at a mean follow-up of 44.3 months (36 to 76) showed no difference in the time to physeal closure between the involved and uninvolved side. Measurement of epiphyseal and physeal development showed continued growth and remodelling in all patients. Use of this device provided epiphyseal stability and maintained the capacity for physeal recovery and growth following treatment for both unstable and stable slipped capital femoral epiphysis

Aims. The aims of this study were to evaluate the abductor function in moderate and severe slipped capital femoral epiphysis (SCFE), comparing the results of a corrective osteotomy at the base of the femoral neck and osteoplasty with 1) in situ epiphysiodesis for mild SCFE, 2) contralateral unaffected hips, and 3) hips from healthy individuals. Patients and Methods. A total of 24 patients (mean age 14.9 years (. sd. 1.6); 17 male and seven female patients) with moderate or severe SCFE (28 hips) underwent base of neck osteotomy and osteoplasty between 2012 and 2015. In situ epiphysiodesis was performed in seven contralateral hips with mild slip. A control cohort was composed of 15 healthy individuals (mean age 16.5 years (. sd. 2.5); six male and nine female patients). The abductor function was assessed using isokinetic dynamometry and range of abduction, with a minimum one-year follow-up. Results. We found no differences in mean peak abductor torque between the hips that underwent osteotomy and those that received in situ epiphysiodesis (p = 0.63), but the torque was inferior in comparison with contralateral hips without a slip (p < 0.01) and hips from control individuals (p < 0.001). The abduction strength was positively correlated with the range of hip abduction (R = 0.36; p < 0.001). Conclusion. Although the abductor strength was not restored to normal levels, moderate and severe SCFE treated with osteotomy at the base of the femoral neck and osteoplasty showed abductor function similar to in situ epiphysiodesis in hips with less severe displacement. Cite this article: Bone Joint J 2018;100-B:1524–32

Aims. Slipped capital femoral epiphysis (SCFE) is one of the most common hip diseases of adolescence that can cause marked disability, yet there is little robust evidence to guide treatment. Fundamental aspects of the disease, such as frequency, are unknown and consequently the desire of clinicians to undertake robust intervention studies is somewhat prohibited by a lack of fundamental knowledge. Methods. The study is an anonymized nationwide comprehensive cohort study with nested consented within the mechanism of the British Orthopaedic Surgery Surveillance (BOSS) Study. All relevant hospitals treating SCFE in England, Scotland, and Wales will contribute anonymized case details. Potential missing cases will be cross-checked against two independent external sources of data (the national administrative data and independent trainee data). Patients will be invited to enrich the data collected by supplementing anonymized case data with patient-reported outcome measures. In line with recommendations of the IDEAL Collaboration, the study will primarily seek to determine incidence, describe case mix and variations in surgical interventions, and explore the relationships between baseline factors (patients and types of interventions) and two-year outcomes. Discussion. This is the first disease to be investigated using the BOSS Study infrastructure. It provides a robust method to determine the disease frequency, and a large unbiased sample of cases from which treatment strategies can be investigated. It may form the basis for definitive robust intervention studies or, where these are demonstrated not to be feasible, this may be the most robust cohort study

Obesity is thought to be an aetiological factor for slipped capital femoral epiphysis (SCFE). We analysed changes in the incidence of SCFE in Scotland over the last two decades. During this period rates of childhood obesity have risen substantially and evidence for a relationship between these changes and the incidence of SCFE was sought. We found that the incidence of SCFE increased from 3.78 per 100 000 children in 1981 to 9.66 per 100 000 in 2000 (R. 2. = 0.715): a two and a half times increase over two decades. It was seen at a younger age, with a fall in the mean age at diagnosis from 13.4 to 12.6 years for boys (p = 0.007) and 12.2 to 11.6 for girls (p = 0.047). More children under eight years old were seen with SCFE in Scotland in the decade to 2000 than in the previous decade (p = 0.002, R. 2. = 0.346). A close correlation was observed between rising childhood obesity over the last 20 years in Scotland and an increasing incidence of SCFE

Slipped capital femoral epiphysis (SCFE) is uncommon in India and we routinely look for associated metabolic or endocrine abnormalities. In this study we investigated a possible association between vitamin D deficiency and SCFE. All children presenting with SCFE during the study period had their 25-hydroxyvitamin D levels measured as part of an overall metabolic, renal and endocrine status evaluation, which included measurement of body mass index (BMI). Vitamin D status was compared with age-, gender- and habitat-matched controls with acute trauma or sepsis presenting to our emergency department. A total of 15 children (12 boys and three girls) with a mean age of 13 years (. sd. 1.81; 10 to 16) presented for treatment for SCFE during a two-year period beginning in January 2010. Renal and thyroid function was within the normal range in all cases. The mean BMI was 24.9 kg/m. 2. (17.0 to 33.8), which was significantly higher than that of the controls (p = 0.006). There was a statistically significant difference between the mean values of 25-hydroxyvitamin D in the children with SCFE and the controls (11.78 ng/ml (. sd. 5.4) versus 27.06 ng/ml (. sd. 5.53), respectively; p < 0.001). We concluded that, along with high BMI, there is a significant association of vitamin D deficiency and SCFE in India. Cite this article: Bone Joint J 2013;95-B:851–4

We reviewed prospectively, after skeletal maturity, a series of 24 patients (25 hips) with severe acute-on-chronic slipped capital femoral epiphysis which had been treated by subcapital cuneiform osteotomy. Patients were followed up for a mean of 8 years, 3 months (2 years, 5 months to 16 years, 4 months). Bedrest with ‘slings and springs’ had been used for a mean of 22 days (19 to 35) in 22 patients, and bedrest alone in two, before definitive surgery. The Iowa hip score, the Harris hip score and Boyer’s radiological classification for degenerative disease were used. The mean Iowa hip score at follow-up was 93.7 (69 to 100) and the mean Harris hip score 95.6 (78 to 100). Degenerative joint changes were graded as 0 in 19 hips, grade 1 in four and grade 2 in two. The rate of avascular necrosis was 12% (3 of 25) and the rate of chondrolysis was 16% (4 of 25). We conclude that after a period of bed rest with slings and springs for three weeks to gain stability, subcapital cuneiform osteotomy for severe acute-on-chronic slipped capital femoral epiphysis is a satisfactory method of treatment with an acceptable rate of complication

Between June 2001 and November 2008 a modified Dunn osteotomy with a surgical hip dislocation was performed in 30 hips in 28 patients with slipped capital femoral epiphysis. Complications and clinical and radiological outcomes after a mean follow-up of 3.8 years (1.0 to 8.5) were documented. Subjective outcome was assessed using the Harris hip score and the Western Ontario and McMaster Universities osteoarthritis index questionnaire. Anatomical or near-anatomical reduction was achieved in all cases. The epiphysis in one hip showed no perfusion intra-operatively and developed avascular necrosis. There was an excellent outcome in 28 hips. Failure of the implants with a need for revision surgery occurred in four hips. Anatomical reduction can be achieved by this technique, with a low risk of avascular necrosis. Cautious follow-up is necessary in order to avoid implant failure

The aim was to examine the descriptive epidemiology of Slipped Capital Femoral Epiphysis, with respect to geography and time. We extracted all children with a diagnosis of Slipped Capital Femoral Epiphysis from the Clinical Practice Research Database between 1990 and 2014 (24 years). CPRD is the world's largest database of primary care, which encompasses 8% of the UK population. CPRD was linked to Hospital Episode Statistics, and a validation algorithm applied to maximise sensitivity and specificity of the cases finding methodology. Poisson confidence intervals were calculated, and poison regression used. 596 cases of SCFE were identified. The internal validation algorithm supported a SCFE diagnosis in 88% cases. The age and sex distribution of cases mirrored that in the literature, offering external validity to the cases identified. There was no significant change in the incidence of SCFE over the 24-year study period, with the overall incidence being 4.8 cases per 100,00 0–16 year olds. There was no significant geographic variation in SCFE within the UK. There was a positive association with rising socioeconomic deprivation (p<0.01). There was no seasonal variation in presentation. This study found no evidence to support the common belief that SCFE incidence is increasing, and for the first time demonstrated an association with socioeconomic deprivation. The results are important for considering the feasibility of intervention studies, and offer insights into the disease aetiology

Purpose. Slipped capital femoral epiphysis (SCFE) is the most common hip disorder in children 9–15 years old. The epidemiology for SCFE in the total population of Sweden has not yet been described. Methods. In a prospective cohort study, we analysed pre- and postoperative radiographs and medical records for all children treated for SCFE in Sweden 2007–2013, and noted demographic data, severity of slip, and surgical procedures performed. Results. We identified 379 Swedish children with primary SCFE 2007–2013; 162 girls, median age 12 (7–15) years, and 217 boys, median age 13 (4–17) years. The cumulative incidence was 45.8/100 000 for girls and 58.2/100 000 for boys. As an initial symptom, 66% of the children had hip/groin pain and 12% knee pain. At first presentation, 7% of the children had bilateral SCFE. Prophylactic fixation was performed in 43% . Of the remaining children, 21% later developed a contralateral slip. Fixation with implants permitting further growth of the femoral neck was used in 90% of the children. Femoral neck osteotomy was performed for 11 hips. Of 34 treating hospitals, only three treated > 3 children with SCFE annually. Conclusions. The cumulative incidence 2007–2013 in the total population in Sweden showed a mild increase for girls. The male-to-female ratio was lower than previously described for Sweden. Prophylactic fixation was performed in 43% of the children. Fixation with an implant that allows further growth was used for 90% of the children. Most hospitals in Sweden treat < 2 children annually

Aim:. Audit of the outcome of subcapital osteotomy for a series of cases of severe unstable slipped capital femoral epiphysis. Method:. 57 cases of unstable severe slipped capital femoral epiphysis were operated on by a single surgeon between 2000 and 2011. The procedure was performed through the anterior abductor sparing approach. Patients have been followed up prospectively and the results are presented at average follow up is 6.4 years with a minimum of 18 month follow to include all risks of avn. Results:. There were 35 males (average age 13.85 years) and 22 females (average age 12.4 years). Three syndromic cases, 2 Trisomy 21 (with no avn) and one pituitary/corpus callosum agenesis (developed avn) were included. 5 patients (8.7%) developed avn, one syndromic, another with noted avn on pre-operative MRI and the third with partially healed growth plate. Excluding these patients the avn rate was 2/54 (3.7%). Re-operations were performed on the avn group including two head neck debridements and valgus osteotomy, one head neck debridement alone and one arthrodesis. One patient is awaiting debridement and valgus osteotomy. One patient developed chondrolysis and has had no intervention 6 years. 2 patients developed asymptomatic heterotopic bone ossification and the incidence of lateral cutaneous nerve symptoms was 35% none requiring intervention. Leg length difference was less than 1 cm in those patients who did not develop avn. Conclusion:. This single surgeon audit shows lower risk of avn than and strengthens the argument for referral to specific centres for such conditions. Level of evidence: IV

Aim. To inform a working group of UK paediatric surgeons (the UK SCFE Study Group) convened to design pertinent trials in slipped capital femoral epiphysis (SCFE), three centres (Bristol, Newcastle and Barts and The London) reviewed the demographics and management of children with SCFE presenting between 2007 and 2012. Method. At all contributing centres with digital PACS records for a minimum of 5 years, a search for the following terms was made of PACS reports: slipped capital femoral epiphysis, slipped upper femoral epiphysis, SCFE and SUFE. From the results, radiographs and electronically stored clinic letters were assessed to confirm the diagnosis and ascertain age at presentation, incidence of bilaterality, chronicity, stability (Loder criteria), management and complications. Results. A total of 134 SCFEs presented between 2007 and 2012 to the three units. The mean age at presentation was 12.8 yrs (range 6–16 yrs). There were 91 males and 43 females. The left hip was nearly twice as commonly involved compared to the right, with bilateral presentation in 26.5% of patients. The most common mode of presentation was acute-on-chronic. Stable slips were over twice as common as unstable. The most common intervention was percutaneous pinning in situ. Open reduction, osteotomy and stabilisation were required in 21% of cases. The most common complications were osteonecrosis (n=17), screw migration/penetration (n=9), leg length discrepancy (n=9) and symptomatic secondary cam with femoroacetabular impingement (n=7). Conclusion. This three-centre UK study gives insight into the demographics and contemporary management of SCFE, acts as a guide to larger audits of current practice throughout the UK and informs the subject and content of potential future randomised clinical trials

We studied radiographs of 125 children (105 boys, 20 girls) with unilateral Legg-Calvé-Perthes’ disease to examine the epiphyseal development of the femoral head in the contralateral (unaffected) hip. The epiphyseal height (EH) and width (EW) of the unaffected hip were measured on the initial anteroposterior pelvic radiograph. In 109 of the patients (87.2%) the EH was below the mean for normal Japanese children and a significantly small EH (below −2 . sd. s) was observed in 23 patients (18.4%). By contrast, the EW of most patients (95.2%) lay within ± 2 SDs of normal values except for six with a significantly small EW. A strong positive linear correlation (R = 0.87) was observed in the EH:EW ratio in the patients. A smaller EH than expected for EW in our series indicated epiphyseal flattening of the femoral head in Legg-Calvé-Perthes’ disease. Our findings support the hypothesis that a delay in endochondral ossification in the proximal capital femoral epiphysis may be associated with the onset of Perthes’ disease

Purpose. This report compares midterm results of open neck osteoplasty + neck osteotomy vs arthroscopic osteoplasty for severe Slipped Capital Femoral Epiphysis (SCFE). Method. Database from 2006 to 2013 identified 22 patients out of 187 operations for SCFE. 12 underwent Open Neck Osteotomy (ONO) and osteoplasty by Ganz surgical dislocation approach. 10 underwent Arthroscopic Osteoplasty (AO). The mean follow-up for the ONO and AO groups were 59 (46 – 70), 36.1 (33 – 46) months respectively. Results. The unpaired t-test showed that the post-operative corrections were significantly better in the ONO than the AO group. Slip angle (16.7° (1°–28.6°) Vs 47.1° (40.2° – 53.5°) p = .0003), head neck offset correction (5mm (2–13mm) Vs 0mm (0mm – 2mm) p = 0.0003), alpha angle (34.6° (23.2°–45.6°) Vs 61.88° (52.1° – 123°) p= 0.0003), Modified Harris Hip Score (MHHS) (90(86.2–99) Vs 75.5 (58.75 – 96.8) p= 0.003) and internal rotation p= 0.0002. Paired t-test showed significant improvement in corrections within the individual groups compared with their own preoperative values. The results of AO group were oblique plane slip angle (55° (47.7° – 63.2°) Vs 47.1° (40.2° – 53.5°) p= 0.001), alpha angle (90.7° (65° – 131°) Vs 61.88° (52.1° – 123°) p= 0.0001), head neck offset (0mm (−3 mm to 0mm) Vs 0mm (0mm – 2mm) p= 0.001) and MHHS (52.7 (28.7 – 89.1) Vs 75.5 (58.75 – 96.8) p= 0.0005). Complications in ONO group were varus malunion (1) and non-union(1) of the osteotomy. In the arthroscopic group persistent impingement in 3 patients and 5 were not able to return to sports. Conclusion. Our results showed improved hip function following arthroscopic osteoplasty in severe SCFE. Considering the risks of an open surgical dislocation we could find that arthroscopy contributed worthy improvement in hip function in low demand patients