Validation of the French version of the Non-Arthritic Hip Score (NAHS) in 113 hip arthroscopy procedures.

BACKGROUND: The Non-Arthritic Hip Score (NAHS) used to evaluate the hip in younger patients is a self-administered questionnaire with 20 items in four sections: pain, symptoms, function, and activities. Although used in France, no transcultural version had been validated. The objective of this study was to translate the NAHS into French then assess the validity, reliability, and sensitivity to change of the French-language version (NAHS-Fr) in younger patients with hip conditions other than osteoarthritis. HYPOTHESIS: The NAHS-Fr demonstrates good validity and reliability when used in younger French-speaking patients with hip pain. MATERIAL AND METHODS: We conducted a prospective observational study in 105 patients (62 males and 43 females) scheduled for surgery on one or both hips (113 hips in total) to treat cam-type femoro-acetabular impingement or labral lesions. Before and 6 months after surgery, each patient completed the NAHS-Fr and Western Ontario and McMaster Osteoarthritis Index (WOMAC). Statistical tests were done to evaluate validity, reliability, and sensitivity to change, as recommended by the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN). RESULTS: The response rate was 100%, confirming that the NAHS-Fr was easy to use. The NAHS-Fr was both valid and reliable. No ceiling or floor effect was detected for the total NAHS-Fr score. All items had Cronbach alpha coefficients greater than 0.8, indicating good internal consistency. External consistency between the NAHS-Fr and WOMAC was negative (-0.676) due to inversely proportional score indexing. Before surgery, the NAHS-Fr and WOMAC scores were strongly and significantly correlated (p<0.0001). The effect size was greater than 0.8, indicating good sensitivity to the change induced by surgery. DISCUSSION: These results confirm the study hypothesis: the NAHS-Fr has the same good psychometric characteristics as does the original version and versions in other languages. The NAHS-Fr is useful for evaluating younger patients with non-osteoarthritic hip pain and can be used by French-speaking surgeons in everyday clinical practice. LEVEL OF EVIDENCE: IV, prospective observational non-comparative cohort study.

Differences in Kinematic Changes From Self-Selected to Fast Speed Gait in Asymptomatic Adults With Radiological Signs of Femoro-Acetabular Impingement.

Femoro-acetabular impingement (FAI) may present as alterations in the skeletal morphology of the hip. Repercussions of FAI can be witnessed in self-selected speed walking as well as physical exercise such as running or fast speed walking. The aim of this study was to investigate changes in kinematics at different gait speeds in subjects presenting with radiological findings invoking FAI. One hundred thirty asymptomatic adults underwent biplanar X-rays with a calculation of 3D hip parameters: acetabular anteversion, abduction and tilt, vertical center edge angle (VCE), femoral anteversion, neck-shaft angle, acetabular coverage of the femoral head, femoral head diameter and neck length. Parameters were classified according to FAI clinical thresholds. Two groups were created: Control group (63 subjects having up to one subnormal hip parameter in favour of FAI) and Radiographic FAI group (67 subjects having ≥2 subnormal hip parameters that might cause FAI). All subjects underwent 3D gait analysis at self-selected and fast speed, from which kinematic parameters were generated. Arithmetic differences between fast and self-selected speed gait were considered as gait changes. Subjects in the Radiographic FAI group had decreased acetabular tilt (24 vs. 19˚), anteversion (19 vs. 16˚), abduction (55 vs. 53˚), femoral anteversion (18 vs. 14˚) and increased VCE (29 vs. 33˚, all p<0.05), compared to controls. Changes from self-selected to fast speed showed that subjects in the Radiographic FAI group had lower range of motion (ROM) pelvic rotation (7 vs. 4˚) and ROM hip flexion/extension (10 vs. 7˚), reduced hip extension (-4 vs. -2˚) and step length (16 vs. 13 cm; all p<0.05). The Radiographic FAI group had decreased acetabular abduction, anteversion and femoral anteversion in favour of FAI. When adapting from self-selected to fast speed gait, the Radiographic FAI group seemed to limit pelvic rotation and hip flexion/extension resulting in a decrease in step length. These kinematic limitations were previously reported in subjects with symptomatic FAI. Gait analysis could be considered as a functional diagnostic tool to assess FAI along with radiological assessment.

Better sex after hip arthroscopy; Sexual dysfunction in patients with femoro-acetabular impingement syndrome.

BACKGROUND: Femoro-acetabular impingement syndrome (FAIS) is a common cause of hip pain and functional decline. The quality of life of affected patients has been shown to be significantly diminished, with potential alterations in the ability to perform activities of daily living and recreation, including sexual function. Hip arthroscopy is the surgical technique recognized as the gold standard in FAIS. The aim of this study was to research the relationship between hip arthroscopy due to FAIS and pre- and postoperative sexual function. HYPOTHESIS: The hypothesis of the study was that sexual dysfunction would be common during the preoperative period but would significantly improve after surgery. MATERIALS AND METHODS: This retrospective study included 96 patients aged 18 to 55 years, who underwent hip arthroscopy for a FAIS diagnosis between 2015 and 2021, with a minimum follow-up of one year. Exclusion criteria were a bilateral symptomatic hip condition, history of ipsilateral hip or knee surgery, history of urological or gynecological conditions, sexual dysfunction, or a history of hip osteonecrosis or osteoarthritis. The Female Sexual Function Scale (FSFI) was used to evaluate sexual dysfunction in females and the International Erectile Function Index (IIEF-5) for males. RESULTS: The patients comprised 56.3% males and 43.82% females with a mean age of 35.3±8.3 years. Sexual dysfunction was determined preoperatively in 85.2% of the males and in 57.1% of the females. Overall improvement after surgery was statistically significant. Signs of pudendal nerve damage were seen during the postoperative period in 29 (30.2%) patients. The change in total sexual scores was significantly correlated with nerve symptoms and regression analysis showed that traction time was a significant risk factor for pudendal nerve symptoms. DISCUSSION: Sexual dysfunction is a common trait of patients suffering from FAIS and the majority of patients significantly benefit from the procedure. Sexual dysfunction persists in a category of patients during the postoperative period, regardless of the type of lesion, and this phenomenon is associated with transient pudendal nerve symptoms, which are more likely to occur with longer traction times and thus represent a clear risk factor. LEVEL OF EVIDENCE: IV.

Elimination of a Postoperative Brace Does Not Increase Complications Following Hip Arthroscopy.

Background The practice of routine postoperative bracing to limit abduction and internal rotation, along with weight-bearing restrictions after hip arthroscopy (HA), varies significantly among surgeons. It is unclear whether the use of a postoperative brace improves short-term outcomes in patients undergoing HA. The purpose of this study was to determine the differences in patient outcomes before and after eliminating routine usage of a postoperative brace. Methods A retrospective review was conducted of 176 adult patients undergoing HA by a single, high-volume surgeon. The no-brace protocol was implemented in October 2020. The patients were divided into two groups: pre-implementation (January-October 2020) and post-implementation (October 2020-April 2021). Twenty-three patients that used a brace during the post-implementation period were excluded. All patients had weight-bearing restrictions with crutches for three weeks postoperatively. The primary endpoint was any complication in the first six weeks postoperatively. Results There were no significant differences in demographics between groups, although the body mass index in the brace group was higher (28.1 vs. 26.4 kg/m2, p = 0.066) and the rate of additional procedures performed was higher in the brace group (55.2% vs. 40.1%, p = 0.056). There was no significant difference in postoperative outcomes between groups when looking at 90-day emergency department visits (1.7% vs. 0%, p = 0.548), complications at two (1.7% vs. 1.7%, p = 1.000) and six weeks (0% vs. 1.7%, p = 0.341) postoperatively, all complications in the first six weeks (1.7% vs. 1.7%, p = 1.000), and continued pain at six weeks (10.3% vs. 16.7%, p = 0.238). Conclusion The brace and no-brace groups were similar demographically. Patients undergoing HA with no brace and crutches experienced no significant differences in pain or complications in comparison to those receiving a traditional bracing protocol. Routine use of a postoperative brace may not be necessary in this population.

Change in Postoperative Weightbearing Protocol Does Not Increase Postoperative Complications Following Hip Arthroscopy for Femoroacetabular Impingement Syndrome.

Background Postoperative rehabilitation protocols, including weightbearing restrictions following hip arthroscopy (HA) for femoracetabular impingement syndrome (FAIS), vary widely among surgeons, from complete non-weightbearing to immediate weightbearing as tolerated; it is unclear if weightbearing restrictions affect short-term outcomes in patients undergoing HA. The purpose of this study is to evaluate patients undergoing hip arthroscopy for FAIS before and after a change in weightbearing protocol, from partial weightbearing with crutches for three weeks to weightbearing and weaning from crutches as tolerated, by examining postoperative outcomes. We hypothesize that the change in weightbearing protocol will have no significant effect on patient outcomes. Methods A retrospective review was conducted of 211 patients undergoing hip arthroscopy by a single high-volume surgeon. The change in weightbearing was implemented in February 2022; previously, all patients were toe-touch weightbearing with crutches for the first three weeks postoperatively. Following this change, patients were allowed to weightbear as tolerated with crutches immediately and wean from crutches as tolerated. The patients were divided into two groups: 119 patients pre-implementation (January 2021 to January 2022) and 92 patients post-implementation (February 2022 to December 2022). The primary endpoint was any complication in the first six weeks postoperatively, divided into complications at two and six weeks, emergency department returns in the first 90 days, reoperations in the first 30 days, and pain at six weeks. We also compared patient-reported outcomes at six weeks. Results There were no significant differences in demographics between groups. There were no significant differences in postoperative outcomes between patients that had weightbearing restrictions and those that did not when looking at 30 day return to operating room (0 vs 0%, p=1.000), 90-day return to emergency department (8.4 vs. 13.0%, p=0.386), two-week complications (2.5 vs. 6.5%, p=0.279), six-week complications (1.7 vs. 1.1%, p=1.000), pain score at six weeks postoperatively (0.34 vs. 0.33, p=0.971), any pain at six weeks postoperatively 37.8 vs. 32.6%, p=0.523), and six-week Patient-Reported Outcomes Measurement Information System (PROMIS) physical function (PF) score (36.0 vs. 34.5, p=0.330). Conclusion Patients undergoing HA after the discontinuation of a mandatory period of protected weightbearing did not experience any significant increase in complications or continued pain, and patient-reported outcomes were similar. Routine postoperative weightbearing restrictions may not be necessary for patients undergoing hip arthroscopy for femoroacetabular impingement syndrome. Further study is required to validate these findings and determine the optimal postoperative protocol for this patient population.

Conservative vs. Surgical Management for Femoro-Acetabular Impingement: A Systematic Review of Clinical Evidence.

Femoro-acetabular impingement (FAI) syndrome is one of the most studied conditions in sports medicine. Surgical or conservative approaches can be proposed for treating FAI, although the best standard of care is not established yet. Our aim is to provide a comprehensive review of the best treatment for FAI syndrome evaluating differences in outcomes between surgical and non-operative management. A literature search was carried out on the PubMed, EMBASE, Scopus, and PEDro databases, using the following keywords: "femoroacetabular impingement", "FAI", in association with "surgery", "arthroscopy", "surgical" and "conservative", "physiotherapy", "physical therapy", "rehabilitation", "exercise". Only Level I RCTs were included. Four articles were selected for this systematic review. Our analysis showed different therapeutic protocols, follow-up periods, and outcomes; however, three out of the four studies included favored surgery. Our study demonstrates beneficial effects for both arthroscopic treatment and a proper regimen of physical therapy, nevertheless a surgical approach seemed to offer superior short-term results when compared to conservative care only. Further trials with larger sample sizes and longer follow-ups are needed to assess the definitive approach to the FAI condition.

Can Lateral Offset Be Used as a Predictive Marker for Proximal Femur Disorders?

Purpose: When the lateral offset (LO) changes, the forces acting on the head and neck of the femur change. Increase or decrease in LO can cause instability and possible dislocation of the implant. In addition, when the offset is reduced, more force is needed to balance the pelvis by the abductor muscles, and the force that occurs along the hip joint increases and causes wear and tear. In this study we aimed to investigate whether there is a correlation between LO and proximal femur morphology, and according to the results we aimed to investigate whether the LO can be used as a predictive marker for the risk of femoral neck fractures, osteoarthritis or femoroacetabular impingement. Methods: Femur length, femur neck length, femoral neck-shaft angle (NSA), anteroposterior (a-p) and superoinferior (s-i) diameters of femoral head and neck, and LO were measured on 82 dry adult femora of unknown age and gender from Turkish population. Results: There was no statistically significant correlation between the LO and a-p and s-i diameters of femoral head or neck. However, there was found statistically significant correlation between LO and femoral NSA (p < 0.01), femoral neck length (p < 0.05) and femur length (p < 0.01). Conclusion: High LO values can be used as an indicator for neck fractures, a negative marker for OA, but LO does not appear to be used as an indicator for FAI.

Isolated arthroscopic treatment of intra-articular pathologies in mild hip dysplasia: a short-term case control study.

PURPOSE: The aim is to compare the results of isolated hip arthroscopy in patients with borderline dysplasia with Lateral center edge angle (LCEA) between 18° and 25° with a control group of patients with normal LCEA (> 25°). METHODS: Fifty hip arthroscopies performed in 45 patients were retrospectively evaluated. Exclusion criteria were: age > 40, hip arthritis > grade 2 according to Tonnis classification, femoral head avascular necrosis, pediatric's orthopaedics conditions and true dysplasia with LCEA < 18°.Two groups were identified: group A with 15 hips with LCEA between 25° and 18° and Group control B made of 35 hips with LCEA > 25°. RESULTS: The groups were homogeneous for demography and pre-operative WOMAC and HOOS. Osteoplasty for CAM were performed in 100% of patients in both groups, only in 12 hips (34.4%) in group B we had both femoral and acetabular osteoplasty. Labral repair was performed in 86% of patients in group A, in 60% of patients in group B, capsular plication in 93% of group A, in 5% of case of group B. WOMAC and HOOS statically significant improved in both groups at final follow-up (24 months). No cases in both groups required conversion to total hip arthroplasty. Clinical outcomes of study group were comparable to the control group. CONCLUSION: Even if the present small series is not conclusive, we suggest isolated arthroscopic management of patients with FAI and LCEA between 18° and 25°, but capsular plication and careful labral management are strongly recommended. LEVEL OF EVIDENCE: Level IV.

Is a Femoro-Acetabular Impingement Type Cam Predictable after Slipped Capital Femoral Epiphysis?

(1) Background: Previous studies have proven a high incidence of a femoro-acetabular impingement (FAI) type cam in patients sustaining a slipped capital femoral epiphysis (SCFE). Thus, the current study analyzed, if a cam deformity is predictable after SCFE treatment; (2) Methods: 113 cases of SCFE were treated between 1 January 2005 and 31 December 2017. The radiological assessment included the slip angle after surgery (referenced to the femoral neck (epiphyseal tilt) and shaft axis as Southwick angle) and the last available lateral center edge angle (LCEA), the acetabular- and alpha angle. A correlation was performed between these parameters and the last alpha angle to predict a FAI type cam; (3) Results: After a mean follow-up of 4.3 years (±1.9; 2.0-11.2), 48.5% of the patients showed a FAI type cam and 43.2% a dysplasia on the affected side. The correlation between the epiphyseal tilt and alpha angle was statically significant (p = 0.017) with a medium effect size of 0.28; (4) Conclusions: The postoperative posterior epiphyseal tilt was predictive factor to determine the alpha angle. However, the cut-off value of the slip angle was 16.8° for a later occurrence of a FAI type cam indicating a small range of acceptable deviations from the anatomical position for SCFE reconstruction.

Hip Labral Reconstruction: Techniques and Outcomes.

PURPOSE OF REVIEW: With increased understanding of the biomechanical function of the acetabular labrum, more attention has been directed towards surgical techniques that preserve or restore normal joint anatomy. While labral repair has been shown to produce superior outcomes to labral debridement, repair is not always possible in the setting of severe labral intrasubstance tearing or deficiency. These patients were previously left without suitable arthroscopic treatment options. RECENT FINDINGS: Labral reconstruction is an emerging procedure that has been shown to offer promising outcomes for traditionally difficult-to-treat hip pathology. Short- and mid-term follow-up studies have consistently demonstrated significant improvement in patient-reported outcomes, function, and patient satisfaction postoperatively, often despite less favorable preoperative characteristics. Labral reconstruction is a viable arthroscopic treatment option that has been shown to reliably produce clinically meaningful results in patients with severe labral pathology that is not amenable to repair/refixation or augmentation.

Which anatomical conditions are associated with limitations of the hip function after SCFE?

BACKGROUND: Patients sustained a slipped capital femoral epiphysis (SCFE) might have symptoms beyond their stabilization surgery in the childhood. METHODS: 35 patients with a SCFE were treated in our clinic and available for a clinical follow-up. The results were compared in dependence of the presence of dysplasia, acetabular retroversion or a FAI type CAM. RESULTS: A FAI type CAM led to significant inferior results (p < 0.05), especially in combination with a retroversion. CONCLUSIONS: The clinical outcome seemed to be influenced by the presence of a FAI type CAM or a combination with a retroversion, which might aggravate the femoro-acetabular conflict. LEVEL OF EVIDENCE: III, retrospective.

Transient regional osteoporosis of the hip with extensive bone marrow edema (BME): Dramatic improvement after three months of Alendronate therapy.

Transient osteoporosis of the hip, also termed transient bone marrow edema, is a painful condition often occurring after trivial trauma. It can be diagnosed with MRI in patients whose radiographs are negative or inconclusive. In this case report we describe a 39-year-old female patient with this rare entity, who was successfully treated with oral Alendronate, active vitamin D and calcium supplementation combined with avoiding of weight bearing on the affected hip. She improved clinically within three months and on contrast enhanced MRI studies, as performed before and after treatment, complete regression of bone marrow edema was shown already after three months of treatment. The literature was reviewed regarding the pathophysiology of transient osteoporosis of the hip and the beneficial effects of Alendronate in this domain. The report is important because it will increase the awareness among clinicians and radiologists about this entity, as in neglected cases transient regional osteoporosis of the hip may progress to avascular necrosis with complete loss of hip function.

A three-dimensional measurement method on MR arthrography of the hip to classify femoro-acetabular impingement.

PURPOSE: (1) To investigate correlations between different types of FAI and the ratio of acetabular volume (AV) to femoral head volume (FV) on MR arthrography. (2) To assess 2D/3D measurements in identifying different types of FAI by means of cut-off values of AV/FV ratio (AFR). MATERIALS AND METHODS: Alpha angle, cranial acetabular version, acetabular depth, lateral center edge angle, AV, and FV of 52 hip MR arthrography were measured. ANOVA test correlated different types of FAI with AFR. ROC curves classified FAI by cut-off values of AFR. Accuracy of 2D/3D measurements was calculated. RESULTS: ANOVA test showed a significant difference of AFR (p value < 0.001) among the three types of FAI. The mean values of AFR were 0.64, 0.74, and 0.89 in cam, mixed, and pincer types, respectively. Cut-off values of AFR were 0.70 to distinguish cam types from mixed and pincer types, and 0.79 to distinguish pincer types from cam and mixed types. Cut-off values identified 100%, 73.9%, and 55.6% of pincer, cam, and mixed types. 2D and 3D classifications of FAI showed accuracy of 40.4% and 73.0%. CONCLUSIONS: 3D measurements were clearly more accurate than 2D measurements. Distinct cut-off values of AFR discriminated cam types from pincer types and identified pincer types in all cases. Cam and mixed types were not accurately recognized.

Validation of the French version of the self-administered international hip outcome tool-33 questionnaire.

INTRODUCTION: To evaluate the effectiveness of new treatments, whether conservative or surgical, a self-administered questionnaire for hip pain targeted at physically active patients 18 to 60 years of age, named the international Hip Outcome Tool-33 (iHOT-33), was developed and validated in 2012. Since there is no French version available and we are acutely aware of transcultural variations, we conducted a prospective study to: 1) translate, and then 2) validate this questionnaire into international French. HYPOTHESIS: The iHOT-33-Fr questionnaire is a valid and reliable tool for evaluating hip pain in a young, francophone population. MATERIALS AND METHODS: Translation of the questionnaire was done according to the standardized method described by Beaton and the final version of the iHOT-33-Fr was validated using the COSMIN methodology. The data were collected prospectively at multiple sites. The reliability of the iHOT-33-Fr questionnaire was evaluated using the intraclass correlation coefficient (ICC) and its internal consistency using Cronbach's alpha. The standard error of measurement and minimum detectable change were calculated. The construct validity was evaluated using Pearson's correlation coefficient by comparing the iHOT-33-Fr with the Hip disability and Osteoarthritis Outcome Score (HOOS-Fr) and Nonarthritic Hip Score (NAHS-Fr). RESULTS: In all, 101 patients filled out the questionnaires. The ICC was 0.87. The Cronbach alpha was 0.95. The standard error of measurement was 6.4 and the minimum detectable change was 1.8. The correlation between the iHOT-33-Fr and the HOOS-Fr was 0.86, while the correlation between the iHOT-33-Fr and the NAHS-Fr was 0.75. DISCUSSION: Our results show that the metrological qualities of the iHOT-33-Fr are comparable to those of the original version and the versions translated into other languages. This study demonstrates that the iHOT-33-Fr is valid, reproducible and comparable to the original iHOT-33. It can be used by francophone surgeons treating symptomatic hip disease in young, active patients. LEVEL OF EVIDENCE: IV.

Deriving alpha angle from anterior-posterior dual-energy x-ray absorptiometry scans: an automated and validated approach.

Introduction: Alpha angle (AA) is a widely used imaging measure of hip shape that is commonly used to define cam morphology, a bulging of the lateral aspect of the femoral head. Cam morphology has shown strong associations with hip osteoarthritis (OA) making the AA a clinically relevant measure. In both clinical practice and research studies, AA tends to be measured manually which can be inconsistent and time-consuming. Objective: We aimed to (i) develop an automated method of deriving AA from anterior-posterior dual-energy x-ray absorptiometry (DXA) scans; and (ii) validate this method against manual measures of AA. Methods: 6,807 individuals with left hip DXAs were selected from UK Biobank. Outline points were manually placed around the femoral head on 1,930 images before training a Random Forest-based algorithm to place the points on a further 4,877 images. An automatic method for calculating AA was written in Python 3 utilising these outline points. An iterative approach was taken to developing and validating the method, testing the automated measures against independent batches of manually measured images in sequential experiments. Results: Over the course of six experimental stages the concordance correlation coefficient, when comparing the automatic AA to manual measures of AA, improved from 0.28 [95% confidence interval 0.13-0.43] for the initial version to 0.88 [0.84-0.92] for the final version. The inter-rater kappa statistic comparing automatic versus manual measures of cam morphology, defined as AA ³≥60°, improved from 0.43 [80% agreement] for the initial version to 0.86 [94% agreement] for the final version. Conclusions: We have developed and validated an automated measure of AA from DXA scans, showing high agreement with manually measuring AA. The proposed method is available to the wider research community from Zenodo.

Degenerative changes of the hip following in situ fixation for slipped capital femoral epiphysis: a minimum 18-year follow-up study.

INTRODUCTION: In situ fixation (ISF) is currently still the 'gold standard' treatment for slipped capital femoral epiphysis (SCFE) and has shown acceptable results at mid-term follow-up. This study aims to evaluate functional, clinical and radiographic long-term outcomes after this procedure. METHODS: We reviewed 64 SCFE patients (76 SCFE hips) treated with ISF between 1983 and 1998. 82.9% were stable hips and 17.1% unstable according to Loder's definition. Initial radiographs demonstrated a mild slip in 50%, moderate in 41.3% and severe in 8.7% based on the Southwick angle. Long-term outcomes were assessed using the modified Harris Hip Score (mHHS), University of California at Los Angeles (UCLA) and Tegner activity scores, visual analogue scale (VAS) pain, VAS function, flexion-adduction-internal rotation (FADIR) test, extent of internal-rotation at 90° of hip flexion and Tönnis classification for hip osteoarthritis (OA). RESULTS: 10 (15.6%) SCFE hips were converted to a total hip replacement (THR) after a mean of 16 years. 38 (59.4%) patients underwent a clinical and radiographic examination after a mean follow-up of 23 (range 18-33) years. 12 (18.8%) patients were lost to follow-up. 74% of SCFE hips demonstrated degenerative change on radiography or were converted to THR (Tönnis 1: 33.3%, 2: 18.5%, 3 or THR: 22.2%). There were 3 cases of avascular necrosis (AVN) all in unstable hips. Mean mHHS was 86.8/100, UCLA activity score 7.5/10, Tegner activity score 3.8/10, VAS pain 1.7/10 and VAS function 1.5/10. 20% of SCFE hips were found to have a positive FADIR-test and a limited internal-rotation of 19.7° versus 36.1° (p < 0.001) in contralateral normal hips. DISCUSSION: This long-term follow-up study of ISF for SCFE shows that although complication rates in terms of AVN are low, a high number of patients become symptomatic and have a limited function. Degenerative changes are common with 22.2% of hips developing end-stage hip OA (Tönnis 3 or THR). It is important that patients and parents are informed about these risks.

Hip preservation.

Classical indications for hip preserving surgery are: femoro-acetabular impingement (FAI) (intra- and extra-articular), hip dysplasia, slipped capital femoral epiphysis, residual deformities after Perthes disease, avascular necrosis of the femoral head.Pre-operative evaluation of the pathomorphology is crucial for surgical planning including radiographs as the basic modality and magnetic resonance imaging (MRI) and/or computed tomography (CT) to evaluate further intra-articular lesions and osseous deformities.Two main mechanisms of intra-articular impingement have been described: (1) Inclusion type FAI ('cam type').(2) Impaction type FAI ('pincer type').Either arthroscopic or open treatment can be performed depending on the severity of deformity.Slipped capital femoral epiphysis often results in a cam-like deformity of the hip. In acute cases a subcapital re-alignment (modified Dunn procedure) of the femoral epiphysis is an effective therapy.Perthes disease can lead to complex femoro-acetabular deformity which predisposes to impingement with/without joint incongruency and requires a comprehensive diagnostic workup for surgical planning.Developmental dysplasia of the hip results in a static overload of the acetabular rim and early osteoarthritis. Surgical correction by means of periacetabular osteotomy offers good long-term results. Cite this article: EFORT Open Rev 2020;5:630-640. DOI: 10.1302/2058-5241.5.190074.

Long-term follow-up of patients undergoing the modified Dunn procedure for slipped capital femoral epiphysis.

AIMS: Our retrospective analysis reports the outcome of patients operated for slipped capital femoral epiphysis using the modified Dunn procedure. Results, complications, and the need for revision surgery are compared with the recent literature. METHODS: We retrospectively evaluated 17 patients (18 hips) who underwent the modified Dunn procedure for the treatment of slipped capital femoral epiphysis. Outcome measurement included standardized scores. Clinical assessment included ambulation, leg length discrepancy, and hip mobility. Radiographically, the quality of epiphyseal reduction was evaluated using the Southwick and Alpha-angles. Avascular necrosis, heterotopic ossifications, and osteoarthritis were documented at follow-up. RESULTS: At a mean follow-up of more than nine years, the mean modified Harris Hip score was 88.7 points, the Hip Disability and Osteoarthritis Outcome Score (HOOS) 87.4 , the Merle d'Aubigné Score 16.5 points, and the UCLA Activity Score 8.4. One patient developed a partial avascular necrosis of the femoral head, and one patient already had an avascular necrosis at the time of delayed diagnosis. Two hips developed osteoarthritic signs at 14 and 16 years after the index operation. Six patients needed a total of nine revision surgeries. One operation was needed for postoperative hip subluxation, one for secondary displacement and implant failure, two for late femoroacetabular impingement, one for femoroacetabular impingement of the opposite hip, and four for implant removal. CONCLUSION: Our series shows good results and is comparable to previous published studies. The modified Dunn procedure allows the anatomic repositioning of the slipped epiphysis. Long-term results with subjective and objective hip function are superior, avascular necrosis and development of osteoarthritis inferior to other reported treatment modalities. Nevertheless, the procedure is technically demanding and revision surgery for secondary femoroacetabular impingement and implant removal are frequent.Cite this article: 2020;1-4:80-87.

Prevalence of femoro-acetabular impingement in non-arthritic patients with hip pain: a meta-analysis.

PURPOSE: As the prevalence of femoro-acetabular impingement syndrome (FAIS) in symptomatic patients who lack evidence of hip osteoarthritis (OA) remains to be described, the purpose of this study was to calculate the prevalence of FAIS in this patient population. METHODS: Libraries of PubMed, Embase, and Ovid were systematically reviewed for all studies between 2009 and 2019, investigating femoro-acetabular impingement and hip pain. Level I-IV studies delineating patients with hip pain who do not have OA (Tonnis or Outerbridge grades < three) were included. Demographics, outcomes, radiographic parameters, and criteria were entered into a meta-analysis to calculate the incidence of FAIS in non-arthritic symptomatic hips. RESULTS: In total, 2264 patients (2758 hips) were included in the pooled analysis. Weighted mean age was 31 years. The incidence of FAIS in patients with no evidence of osteoarthritis but who complain of hip pain is 61% (47.3-74.4%). In total, 1483 hips were diagnosed with FAIS. Of the studies that described the rates of all three of the various subtypes of FAIS in their reports, 37% had a combined-type, 38% had a cam-type, and 25% had a pincer-type FAIS. CONCLUSION: Femoroacetabular impingement should be suspected in 47 to 74% of patients with hip pain and without arthritis. Physicians must maintain a high index of suspicion for FAIS in young patients presenting with hip pain, as FAIS is a common and treatable condition that, if left alone, may lead to hip degeneration.

Sclerotic lesions of the femoral head-neck junction for diagnosis of femoroacetabular impingement.

The morphological characteristics associated with a diagnosis of femoroacetabular impingement (FAI) observed on plain radiographs can also be seen in subjects without hip joint symptoms. Therefore, the purpose of this study was to investigate whether sclerotic lesions on femoral head-neck junction (FHNJ) could be used as a supplemental diagnostic feature. A total of 128 hips from 119 patients (43 male and 76 female) diagnosed with FAI and 24 hips from 21 patients (2 male and 19 female) with other hip pathologies as control were compared in this study. Using standing frog-leg plain radiographs, the prevalence of sclerotic lesions on the FHNJ was established. Additionally, the pixel intensity (PI) of the sclerotic lesions between the FAI and the control groups were quantitatively compared. Sclerotic lesions were present in 96.1% of FAI hips (123 of 128) and only 37.5% of control hips (9 of 24) (p < 0.05). The ratio of PI in the FAI group was significantly higher (approximately 10%) than in the control group (p < 0.05). The evaluation of sclerotic lesions may be used as a supplement to aid in the diagnosis of FAI.