Type Femoroacetabular Impingement Research Articles

Association Between Chondrolabral Junction Breakdown and Conversion to Total Hip Arthroplasty After Hip Arthroscopy for Symptomatic Labral Tears: Minimum 8-Year Follow-up.

Arthroscopic treatment of femoroacetabular impingement (FAI) and symptomatic labral tears confers short- to midterm benefits, yet further long-term evidence is needed. Moreover, despite the physiological and biomechanical significance of the chondrolabral junction (CLJ), the clinical implications of damage to this transition zone remain understudied. To (1) report minimum 8-year survivorship and patient-reported outcome measures after hip arthroscopy for FAI and (2) characterize associations between outcomes and patient characteristics (age, body mass index, sex), pathological parameters (Tönnis angle, alpha angle, type of FAI, CLJ breakdown), and procedures performed (labral management, FAI treatment, microfracture). Cohort study; Level of evidence, 3. This retrospective cohort study included patients who underwent primary hip arthroscopy for symptomatic labral tears secondary to FAI by a single surgeon between 2002 and 2013. All patients were ≥18 years of age with minimum 8-year follow-up and available preoperative radiographs. The primary outcome was conversion to total hip arthroplasty (THA), and secondary outcomes included revision arthroscopy, patient-reported outcome measures, and patient satisfaction. CLJ breakdown was assessed using the Beck classification. Kaplan-Meier estimates and weighted Cox regression were used to estimate 10-year survivorship (no conversion to THA) and identify risk factors associated with THA conversion. In this study of 174 hips (50.6% female; mean age, 37.8 ± 11.2 years) with mean follow-up of 11.1 ± 2.5 years, the 10-year survivorship rate was 81.6% (95% CI, 75.9%-87.7%). Conversion to THA occurred at a mean 4.7 ± 3.8 years postoperatively. Unadjusted analyses revealed several variables significantly associated with THA conversion, including older age; higher body mass index; higher Tönnis grade; labral debridement; and advanced breakdown of the CLJ, labrum, or articular cartilage. Survivorship at 10 years was inferior in patients exhibiting severe (43.6%; 95% CI, 31.9%-59.7%) versus mild (97.9%; 95% CI, 95.1%-100%) breakdown of the CLJ (P < .001). Multivariable analysis identified worsening CLJ breakdown (weighted hazard ratio per 1-unit increase, 6.41; 95% CI, 3.11-13.24), older age (1.09; 95% CI, 1.04-1.14), and higher Tönnis grade (4.59; 95% CI, 2.13-9.90) as independent negative prognosticators (P < .001 for all). Although most patients achieved favorable minimum 8-year outcomes, several pre- and intraoperative factors were associated with THA conversion; of these, worse CLJ breakdown, higher Tönnis grade, and older age were the strongest predictors.

No Differences in Clinical Outcomes Between Hip Arthroscopy With Versus Without Capsular Closure in Patients With Cam- or Mixed-Type Femoroacetabular Impingement: A Randomized Controlled Trial

PurposeTo compare two-year clinical outcomes of primary hip arthroscopy with versus without capsular closure after interportal capsulotomy in patients with cam- or mixed- type femoroacetabular impingement (FAI). MethodsPatients with cam- or mixed-type FAI undergoing primary hip arthroscopy with interportal capsulotomy were prospectively enrolled in this randomised controlled trial (RCT) and allocated into either capsular closure or no capsular closure groups. Patients were blinded to group allocation. Clinical outcomes were assessed preoperatively and at 2 years follow-up using the International Hip Outcome Tool (iHOT-12), modified Harris Hip Score (mHHS), and six subsections of the Copenhagen Hip and Groin Outcome Score (HAGOS). Complications and reoperations were noted. ResultsEighty-four patients (100 hips) were enrolled, 49 hips in the capsular closure group and 51 in the no capsular closure group, with no significant differences in age (28.5±7.5 vs 30.4±8.4, p=0.261), BMI (23.5±3.0 vs 23.4±1.9, p=0.665), and sex distribution (F: 10.2% vs 13.7%, p=0.760). Four patients were lost to follow-up (2.0% vs 5.9%, p=0.618) and 6 had reoperations (6.1% vs 5.9%, p=1.000), which left 45 hips per group for clinical assessment. There were no significant differences between groups in the net change of iHOT-12 (28.3±19.6 vs 32.5±22.7, p=0.388), mHHS (7.6±13.1 vs 7.5±10.2, p=0.954), and subsections of HAGOS (p>0.05). Complication rates were also similar between groups (p>0.05). ConclusionThe present RCT compared primary hip arthroscopy with versus without capsular closure after interportal capsulotomy in a male-dominated, non-dysplastic, non-arthritic cohort with cam- or mixed- type FAI, and found no significant differences in patient-reported clinical outcomes, complication rates, or reoperation rates. Level of EvidenceLevel I, Randomised Controlled Trial

Radiological signs of femoroacetabular impingement are linked to pelvic version in asymptomatic subjects

IntroductionWith the recent interest in hip-spine relationship, the link between femoroacetabular impingement (FAI) and the lumbar-pelvic-femoral complex (LPFC) appears decisive. The objectives of this study were (1) to compare the pelvic version, as well as (2) all the parameters of the LPFC between two populations of healthy subjects, comparing those with radiological signs of FAI to those without and finally, (3) to evaluate the LPFC parameters according to the type of FAI. HypothesisAsymptomatic subjects with radiological signs of FAI had superior pelvic anteversion. Materials and methodThis retrospective study was based on a prospective cohort of 118 voluntary asymptomatic patients including 62 men (52.5%) with a mean age of 25.6 years±4.4 (19–39). The following parameters: pelvic version (PV), pelvic incidence (PI), lumbar lordosis (LL), sacral slope (SS), hip flexion, intrinsic (IER) and extrinsic (EER) extension reserve were measured using EOS imaging™ in the reference standing position and the lunge position. The radiological signs of FAI (cam, pincer, mixed) were identified on these acquisitions then separated into 2 groups. The first was the group presenting with one or more images of FAI (FAI+) and the second group with no images of FAI (FAI–). ResultsThere were 143 hips in the FAI+ group compared to 93 hips in the FAI– group. There were 36.4% cams and 45% pincers. With an average of 9.08°±7.81 (–11.0; 27.0) versus 12.33°±8.94 (–5.0; 55.0), the PV was significantly lower (p=0.022) in the FAI+ group compared to the FAI– group. A post-hoc power analysis on the primary outcome (PV) confirmed sufficient power (1–β=0.809). Compared to the FAI– group, the cam group presented a significantly lower IER and EER (respectively p=0.014 and p=0.047). The comparative analysis between the FAI– and pincer groups found a significant difference in PI (p=0.001), PV (p<0.001), IER (p=0.017) and hip flexion (p<0.001), SS in lunge position (p=0.031) and EER (p=0.039). ConclusionAsymptomatic subjects with radiographic signs of FAI present with weak pelvic version when standing. This pelvic hyper-anteversion is mainly found in the event of a radiological pincer sign. Level of evidenceIII, retrospective comparative study.

Poster 116: Integrated scRNA-seq and spatial transcriptomics analysis uncovers distinct cellular populations and transcriptomes in human hip synovium between patients with femoroacetabular impingement and osteoarthritis.

Objectives: Osteoarthritis (OA) is a common degenerative joint disease marked by joint dysfunction and chronic pain. Previous studies have outlined a variety of complex factors associated with cartilage degradation, inflammation, and pathological changes in knee synovium. However, hip and knee OA have been established as immunologically distinct types of joint diseases due to unique cytokine profiles of synovial fluid, and data regarding hip OA synovium is scarce1. Evidence suggests that primary hip OA may result from cam-type femoroacetabular impingement (FAI). Thus, cam-type FAI has been considered a unique early-phase model of hip OA, allowing scientists to identify regulators implicated in hip OA development. Integrated single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics (Spatial-seq) provides a powerful means to better understand unique genetic markers underlying signaling pathways and cellular interactions that may be involved in disease progression (i.e., FAI to hip OA). In this study, we hypothesize that FAI and hip OA patients have distinct transcriptomic profiles and signaling pathways in their synovial tissues. We aim to identify the underlying molecular mechanisms by using scRNA-seq, Spatial-seq, and bioinformatic analyses. Methods: De-identified human hip synovial tissues were harvested from patients diagnosed with cam- type FAI or with OA (and accompanying cam morphology) according to approved IRB protocols at the University of Rochester (UR). Tissue samples were digested for scRNA-seq and sectioned for Spatial-seq separately and submitted to UR Genomics Research Center (10X Genomics). Distinct cell populations and differentially expressed genes (DEGs) were identified using bioinformatic tools including Seurat2, Monocle3, RcisTarget4, and CellChat5 R packages. Functional analysis for identified cell subsets was annotated by Gene Ontology term6. Differentiation trajectories of non-hematopoietic cells and cell-cell crosstalk were also evaluated. Results: Unsupervised clustering of FAI and OA hip synovial cells identified four major conserved groups: NK cells, endothelial cells, myeloid cells, and non-hematopoietic cells. Sub-clustering of integrated FAI and OA non-hematopoietic cells further yielded 5 distinct cell types including lining, sublining and transitional fibroblast-like synoviocytes (FLS) as well as endothelial cells and pericytes (Fig. 1A). In comparison to FAI synovium, OA synovium exhibited 4.5-, 5- and 8.5-fold increase in IL11+/CD82+ sublining FLS (cluster 5), pericytes (cluster 7) and SPP1+/KDR+ capillary endothelial cells (cluster 9), respectively (Fig. 1B). To further investigate the origin of these populations, we performed pseudotime analysis and revealed that pericytes may differentiate from C34+/C3+/CXCL14+ sublining perivascular FLS (cluster 6) (Fig. 2A)6. To determine the putative transcription factors (TFs) regulating the differentiation process between these two cell populations, we identified that KLF4, SOX5 and CREB3L2 (CAMP Responsive Element Binding Protein 3 Like 2) are potential key regulators using DNA-binding motif analysis. We also observed an opposite trend in expression of KLF4 and CREB3L2, with the highest expression levels of KLF4 in sublining perivascular FLS (Fig. 2B). Importantly, by integrating scRNA-seq and Spatial-seq datasets, we were able to map spatial location of identified cell clusters in the hip joint synovium, allowing us to further interrogate cell-cell crosstalk. For example, we observed that pericytes are in close proximity to SPP1+/KDR+ capillary endothelial cells (cluster 9) and identified that VISFATIN- (ITGA5+ITGB1) and SPP1-CD44 are critical signaling pathways between these two cell populations in OA synovium (Fig. 3B). Conclusions: OA is the most prevalent degenerative joint disorder and is a primary cause of worldwide disability without any available disease modifying therapies. We believe that our findings will reveal key genetic markers related to hip OA progression and facilitate the development of targeted drug deliveries for future therapeutic applications. Our scRNA-seq analysis revealed unique transcriptomic patterns in the synovial cells between FAI and hip OA patients. Integration of non-hematopoietic cells revealed a significant increase in the number of pericytes and endothelial cells present in OA vs. FAI synovium. This is supported by the evidence of increased vasculature in OA, which in turn may promote enhanced infiltration of myeloid cells, cytokines and chemokines into the synovium, leading to an advanced joint inflammation and disease progression7. Furthermore, we identified that both pericytes and capillary endothelial cells can express visfatin (an adipokine) and may modulate synovial inflammation in OA via integrin-mediated signaling pathways8. This observation aligns with previous studies that highlight a significant contribution of endothelial cell-pericyte interactions to OA pathogenesis8. In addition, our finding of decreased expression of KLF4 in pericytes is consistent with previous reports showing that KLF4 inactivation enhances the expression of pericyte markers9. Our next step is to integrate our scRNA- seq and Spatial-seq datasets of non-hematopoietic cells with myeloid cells to further elucidate how altered cell-cell crosstalk and signaling pathways in synovium may lead to hip OA progression. Indeed, we have analyzed myeloid cells separately, and observed elevated accumulation of “hybrid” macrophages expressing pro- and anti-inflammatory markers (IL10+/IL1 +/IL1 +) in the hip OA compared to FAI synovium.

Midterm results after arthroscopic femoral neck osteoplasty combined with labral debridement for cam type femoroacetabular impingement in active adults

IntroductionArthroscopic labral procedures are frequently undertaken in patients with femoroacetabular impingement (FAI). The role of arthroscopic femoral neck osteoplasty is well established, but less is known about labral procedures. This study evaluates the midterm efficacy and feasibility of arthroscopic osteoplasty with concomitant labral debridement for cam impingement in active adults.MethodsThe present study was conducted according to the STROBE Statement. All 108 patients who underwent primary hip arthroscopy for cam type FAI combined with labral debridement were considered. Axial and anteroposterior plain radiographs of the pelvis were obtained preoperatively to identify the cam deformity and assess the presence of osteoarthritis, the lateral centre-edge angle, and the alpha angle. The ROM (flexion, extension, abduction, adduction, and intra/extra rotation) was evaluated. The following PROMs were administered: visual analogic scale (VAS), Tegner Activity Scale, non-arthritic hip score (NAHS), the international Hip Outcome Tool (iHOT-33) overall score, and related subscales: symptoms and functional limitations, sports and recreational activities, job-related concerns, and social, emotional, and lifestyle concerns.ResultsAt a mean of 2.0 ± 1.1 months, all 108 patients returned to their daily activities with no limitation. At a mean of 2.6 ± 1.4 months, all 108 patients were able to return to sport with no limitation. At 11.9 ± 2.1-month follow-up, no differences were reported in the range of motion compared to baseline: flexion (P = 0.3), extension (P = 0.09), abduction (P = 0.1), adduction (P = 0.3), internal rotation (P = 0.4), and external rotation (P = 0.6). At 72.8 ± 21.7-month follow-up, the mean VAS score was 1.7 ± 3.0, Tegner Activity Scale 3.5 ± 1.4, NAHS 92.1 ± 21.5, iHOT33 83.3 ± 27.2. At a mean of 21.7 ± 15.5 months following the index procedure, 14 of 108 patients had undergone total hip arthroplasty. No further revisions or complications were reported.ConclusionArthroscopic femoral neck osteoplasty with concomitant labral debridement for cam type of FAI in active adults yields the reliable results, with a rate of progression to total hip arthroplasty of 13% (14 of 108) at 3-year follow-up. All patients returned to their daily activities with no limitation 2 months postoperatively. Within 3 months, all patients returned to sport with no limitations. No complication related to the index procedure was reported, and no further arthroscopic procedures were necessary.

Results of Arthroscopic Treatment for Femoroacetabular Impingement

Background. Femoroacetabular impingement (FAI) is one of the most frequent causes of hip pain and limited hip mobility in young and middle-aged patients. It is a result of repeated injury of hip structures, that leads to degenerative changes in hip labrum, cartilage and subchondral bone and provokes progressive development of hip osteoarthritis.&#x0D; Aim of study to analyze own experience of treating patients with femoroacetabular impingement and identify factors affecting its outcomes.&#x0D; Methods. Retrospective, uncontrolled, single-center clinical study included 128 patients with FAI which had 150 surgeries on 149 joints in in the period from 2013 to 2021. All patients underwent physical examination and X-ray diagnostics, their FAI type was identified. The alpha angle of external part of femoral head in anterior-posterior position and in the modified Dunn 45 position, as well as Tonnis angle, lateral central-marginal angle in Ogata modification and the height of articular gap along the lateral (LS) and medial edges (MS) of sclerosed acetabulum part were calculated. The i-HOT-33 and HOS scales were used to assess preoperative status and postoperative results.&#x0D; Results. The average follow-up period was 3.9 years (SD 1.71; min 1.05 and max 8.16). The study included 55 (43.0%) women and 73 (57.0%) men which underwent 64 (42.7%) and 86 (57.3%) surgeries respectively. The most common types of FAI, according to our data, were mixed type (53% of joints) and сam type (27.5% of joints). Insufficient coverage of the femoral head by the acetabulum (borderline dysplasia) in combination with the сam deformity of the femoral head was observed in 18.1%. Pincer-type FAI was observed in 1.4% of joints. We obtained the worst results with a combination of сam deformity and borderline dysplasia in comparison with cam- and mix-type FAI according to the i-HOT-33 and HOS scales. Patients age, deep cartilage damage, irreparable labrum damage and height decrease of the lateral part of the articular gap determined negative effect on treatment results according to the i-HOT-33 and HOS scales.&#x0D; Conclusion. Hip arthroscopy showed good short- and midterm outcomes in patients with FAI. Pain syndrome is most often manifested in patients with pathology of hip soft tissue structures concomitant to FAI. The combination of сam deformity and insufficient femoral head coverage, deep cartilage damage and a height decrease of the articular gap are important predictors of poor treatment results.

Characteristics of Biomechanical and Physical Function According to Symptomatic and Asymptomatic Acetabular Impingement Syndrome in Young Adults.

Femoroacetabular impingement (FAI) is caused by hip joint anomalies. Although asymptomatic and symptomatic FAI have been reported in young adults, information on biomechanical and functional characteristics of FAI is rare. We compared the subjective hip score, range of motion (ROM), dynamic balance, and hip strength between symptomatic FAI (FAIsym) and asymptomatic FAI (FAIasym) groups and healthy controls. Participants (n = 307; men: 155, women: 152) were classified according to morphological abnormalities and hip joint symptoms, comprising symptomatic FAI, asymptomatic FAI, and healthy controls. The Copenhagen Hip and Groin Outcome Score (HAGOS), hip ROM, Y-balance test (YBT), and isokinetic hip strength were measured. The types of FAI were not significantly differenent in both men and women. FAIsym exhibited significantly reduced HAGOS, whereas FAIasym showed no significant difference compared to the healthy group (men: healthy 91.7 vs. FAIasym 87.2 vs. FAIsym 49.9, women: healthy 91.7 vs. FAIasym 86.2 vs. FAIsym 53.9). Hip flexion, adduction, and internal and external rotation ROMs were only significantly reduced in symptomatic FAI. Asymptomatic and symptomatic FAI groups displayed significantly lower YBT scores than healthy controls (men healthy: 84.9 vs. FAIasym: 69.0 vs. FAIsym 58.7, women healthy 79.2 vs. FAIasym 64.0 vs. FAIsym 55.5). Isokinetic hip flexion, adduction, and abduction strengths were significantly lower in FAIsym. In conclusion, FAIasym showed no decrease in muscle strength but displayed reduced dynamic balance. Subjective satisfaction, ROM, muscle strength, and dynamic balance were lower in FAIsym compared to FAIasym and healthy groups.

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.

Nonoperative Management of Femoroacetabular Impingement: Clinical Outcomes at 5-Years--A Prospective Study (143)

Objectives:Mid-term and long-term outcomes data on non-operative management of femoroacetabular impingement (FAI) syndrome remains sparse despite expanding research on the topic. Our purpose is to present 5-year outcomes data utilizing a non-operative protocol on a consecutive series of patients with FAI syndrome.Methods:Between 2013 and 2016, patients were prospectively recruited in a non-operative FAI study. The protocol consisted of an initial trial of rest, physical therapy, and activity modification. Patients who remained symptomatic were offered an intra-articular steroid injection. Patients with recurrent symptoms were offered arthroscopic treatment. Patient-reported outcomes including the modified Harris Hip Score (mHHS) and Non-arthritic Hip Score (NAHS) were collected 1-, 2-, and 5-years after enrollment. We present the 5-year data. Statistical analysis was performed to determine outcomes based on FAI type and treatment.Results:133 hips in 100 patients were enrolled. Sixty-seven hips in 50 patients were available for 5-year follow up. At enrollment, the mean mHHS and NAHS were 69.6±13.1 and 76.3±14.7 respectively. In total, 73% of the cohort was managed non-operatively. Of the 11 patients requiring surgery, six (55%) converted to surgery within one year of enrollment, 4 (36%) converted to surgery between one and 2 years, and one patient converted to surgery between 2 and 5 years. At final follow up, the mean mHHS and NAHS were 89.6±10.7 and 88.0±12.1 respectively. At 1-year follow up, only the activity modification group made a significant increase in mHHS and NAHS (p<0.03), by two year follow up, all three treatment groups had made statistically significant improvements in mHHS and NAHS (p<0.05), by 5-years follow up, the activity modification group and the scope group had maintained their statistically significant improvement in mHHS and NAHS (p<0.03). There was no significant difference in mHHS or NAHS between treatment groups at 5-year follow-up (p>0.4)(Table 1), and no difference in proportion of hips meeting the MCID for mHHS based on treatment course (p=0.961). There was no difference in mHHS or NAHS between FAI types at any time point (p>0.06)(Table 2), or in the proportion of hips that met MCID among FAI types (p=0.511). 72% of patients returned to the same or similar sport/activity level, and there was no difference in the proportion of patients that returned to sports/activities among treatment type (p=0.095) or FAI type (p=0.273).Conclusions:Non-operative management of FAI syndrome is effective in a majority of adolescent patients, with robust improvements in patient-reported-outcomes persisting at 5-year follow-up.

The prevalence of femoroacetabular impingement in asymptomatic hips in Indian population: a radiomorphometric analysis

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; Femoroacetabular impingement (FAI) is a common cause of secondary osteoarthritis of the hip. There are no much studies about the occurrence of FAI in asymptomatic individuals in Indian population. Our objective was to find out the radiological prevalence of FAI in asymptomatic adult Indian population.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods: &lt;/strong&gt;A cross sectional study was carried out in our institution, which is a tertiary care centre, between September 2016 and September 2018 in which in which we studied radiographs of 1600 hips from 800 pelvic x-rays of asymptomatic patients.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results: &lt;/strong&gt;Out of 1600 radiographs of the hips studied 1353 were found to be normal and the remaining 247(15.4%), had features of FAI. 61 hip radiographs (3.8%) showed cam lesions and 9.2 % showed pincer type of lesion.38 hips (2.4%) showed mixed type of FAI.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; Significant number of radiographs of asymptomatic patients showed features of FAI. Further long-term studies are needed to see the proportion of these patients with FAI progressing to secondary osteoarthritis of hip.&lt;/p&gt;

The lateral joint space width is essential for the outcome after arthroscopically assisted mini-open arthrotomy for treatment of a femoroacetabular impingement: an analysis of prognostic factors for the success of this hip-preserving technique.

The purpose of this study was to analyze predicting factors for a conversion to a total hip replacement (THR) after mini-open arthrotomy for treatment of femoroacetabular impingement (FAI). Between 2011 and 2016, we identified 32 patients, who were treated for FAI with a mini-open arthrotomy and received after mean time of 2.1 ± 1.4years a THR. These patients were compared to 47 cases who did not receive a THR (mean follow-up: 4.3 ± 0.7years) to explore pre- and intra-operative factors associated with a conversion to THR. The results were presented in separated Kaplan-Meier curves with log rank test for significance and hazard ratios. A lateral joint space width of > 4mm showed a higher THR-free survival rate compared to < 4mm (p = 0.001); analogously one-sided (acetabular/femoral) 3-4° cartilage damage had a comparable THR-free survival rate than 1-2° kissing lesions (p = 0.001). Furthermore, an intact labrum without treatment and good cartilage status, a refixed labrum after rim resection in case of a pincer type FAI, or a refixed teared labrum were associated with a longer THR-free time than an untreated labrum accompanied by a poor cartilage status or an ossified labrum (p = 0.002). The strongest independent factor for a conversion to THR was femoral cartilage damage grade 1 and higher (p = 0.046). However, the rate of available patients was 53.0%. The success of a joint-preserving mini-open arthrotomy seems to be dependent on the status of the radiological joint space width and the intra-operative cartilage status of the lateral edge.

Nonoperative Management of Femoroacetabular Impingement in Adolescents: Clinical Outcomes at a Mean of 5 Years: A Prospective Study

Background: There is a lack of midterm or long-term outcome data on nonoperative management of femoroacetabular impingement (FAI) syndrome in adolescents despite expanding research mostly focused on arthroscopic management. Purpose: To present 5-year outcome data utilizing a nonoperative protocol on a consecutive series of patients presenting to our clinic with FAI syndrome. Study Design: Cohort study, Level of evidence, 2. Methods: A total of 100 patients (62% female; mean age 15 years) who presented to the clinic for evaluation of hip pain and had at least 1 hip with a positive impingement sign were prospectively recruited. The management protocol consisted of an initial trial of rest, physical therapy, and activity modification. Patients who remained symptomatic were offered an intra-articular steroid injection. Patients with recurrent symptoms were then offered arthroscopic treatment. Patient-reported outcomes (PROs), including the modified Harris Hip Score (mHHS) and the Nonarthritic Hip Score (NAHS) were then collected at a mean 1, 2, and 5 years after the initial evaluation. Results: At enrollment, the mean mHHS and NAHS were 69.6 ± 12.9 and 75.5 ± 15.2, respectively. A total of 51 patients (n = 69 hips) were available at a mean 5-year follow-up, with the mean mHHS and NAHS of 89.5 ± 10.8 and 88.1 ± 12, respectively. There was no significant difference in the mHHS or the NAHS between activity modification and physical therapy, injection, or arthroscopic surgery groups at 5-year follow-up (P > .6) and no difference in the proportion of hips meeting the minimal clinically important difference (MCID) for the mHHS based on treatment course (P = .99). There was no significant difference in the mHHS or the NAHS between FAI types at any time point, or in the proportion of hips that met the MCID among FAI types (P = .64). Also, 11 out of 12 hips that required surgery had surgery in less than 2 years. One hip underwent surgery at 5 years after the initial visit. There was no significant drop-off in the mHHS or the NAHS between the 2-year and 5-year time periods (P > .3). Conclusion: Nonoperative management of FAI syndrome is effective in a majority of adolescent patients, with significant improvements in PROs persisting at a mean 5-year follow-up.

What Is the Impact of a CAM Impingement on the Gait Cycle in Patients with Progressive Osteoarthritis of the Hip?

(1) Background: The femoroacetabular impingement (FAI) type cam leads to a conflict between the acetabular rim and a bony thickening of the femoral neck junction. While maximal excursions in flexion, adduction and internal rotation provoke pain, the aim of this study was to analyze if a cam morphology shows an impact on gait pattern. (2) Methods: Fifty-five patients with end-stage hip osteoarthritis performed gait analysis before hip replacement as well as three, six and 12 months postoperatively. Thirty-three (60%) of them presented an FAI type cam. An ANOVA was used to compare the hip angles in sagittal, frontal and transversal planes between patients with a FAI type cam (group “+cam”) and without (group “−cam”). (3) Results: Before surgery the patients of the +cam-group showed a tendency towards a reduced flexion and internal rotation at the heel strike (p &gt; 0.05). Over time, the differences were adjusted by total hip arthroplasty. (4) Conclusions: We did not find any differences in the gait analysis of patients with a FAI type cam compared to patients without.

Frequency of Acetabulum Retroversion Formation after Reorienting Pelvic Osteotomies in Children Over 7 Years Old with Developmental Dysplasia of the Hip

Background. One of the reasons for the development of the “pincer” type of femoroacetabular impingement are various reorienting pelvic osteotomies, which are widely used in the treatment of children with developmental dysplasia of the hip (DDH).The aim of the study was to evaluate the frequency of formation of retroversion of the acetabulum after reorienting pubic-iliac, iliac-sciatic and triple pelvic osteotomies in children over 7 years old with DDH I–II degree according to Crowe.Material and Methods. The retrospective study is based on the results of radiometry of 60 patients (69 hip joints) at an average age of 11.6±2.9 years with DDH I–II degree according to Crowe who underwent surgical treatment in 2014-2016. The patients were divided into three groups of 20 patients each. Group I underwent an iliac osteotomy. Group II underwent an ilio-sciatic osteotomy. In group III patients, the acetabulum was reoriented by triple (pubo-ilio-sciatic) pelvic osteotomy. In addition to standard radiometry of the hip joints, the following indicators were evaluated: signs of acetabular retroversion (“cross-over”, “posterior wall”, “ischial spine”), as well as the index of acetabular retroversion (ARI).Results. The assessment of the main radiometric parameters of the spatial position and the correction value of the acetabulum was carried out at least 36 months after the surgical treatment. There were no statistically significant differences in the radiometric parameters of the spatial orientation of the acetabulum in group I and II patients (p0.05), except for the degree of bone coverage, which was significantly higher in group II patients (p0.05) than in group II patients, which indicated the presence of hypercorrection. In patients of group III, the values of the above-mentioned indicators varied within the physiological values. Retroversion of the acetabulum was observed in more than half of the patients in group I and in almost all patients in group II. In group III patients, acetabular retroversion was observed in only 3 patients.Conclusion. In the vast majority of cases, a double pelvic osteotomy (pubo-iliac and ilio-sciatic) leads to the formation of hypercorrection of the acetabular fragment and its retroversion in comparison with a triple pelvic osteotomy. The pathological orientation of the acetabulum, despite the achieved stability of the hip joint, can be a morphological substrate for the development of femoro-acetabular impingement and, as a result, coxarthrosis. In the treatment of children with DDH over 7 years old the operation of choice is a triple pelvic osteotomy.

Acetabular Cartilage Thickness Differs Among Cam, Pincer, or Mixed-Type Femoroacetabular Impingement: A Descriptive Study Using In Vivo Ultrasonic Measurements During Surgical Hip Dislocation.

To investigate acetabular cartilage thickness among (1) 8 measurement locations on the lunate surface and (2) different types of femoroacetabular impingement (FAI). Prospective descriptive study comparing in vivo measured acetabular cartilage thickness using a validated ultrasonic device during surgical hip dislocation in 50 hips. Measurement locations included the anterior/posterior horn and 3 locations on each peripheral and central aspect of the acetabulum. The clock system was used for orientation. Thickness was compared among cam (11 hips), pincer (8 hips), and mixed-type (31 hips) of FAI. Mean age was 31 ± 8 (range, 18-49) years. Hips with no degenerative changes were included (Tönnis stage = 0). Acetabular cartilage thickness ranged from 1.7 mm to 2.7 mm and differed among the 8 locations (P < 0.001). Thicker cartilage was found on the peripheral aspect at 11 and 1 o'clock positions (mean of 2.4 mm and 2.7 mm, respectively). At 5 out of 8 locations of measurement (anterior and posterior horn, 1 o'clock peripheral, 12 and 2 o'clock central), cartilage thickness was thinner in hips with pincer impingement compared to cam and/or mixed-type of FAI (P ranging from <0.001 to 0.031). No difference in thickness existed between cam and mixed-type of impingement (P = 0.751). Acetabular cartilage thickness varied topographically and among FAI types. This study provides first baseline information about topographical cartilage thickness in FAI measured in vivo. Thinner cartilage thickness in pincer deformities could be misinterpreted as joint degeneration and could therefore have an impact on indication for hip preserving surgery.

Inter-observer concordance in normal and pathological findings of the hip joint in plain radiographs.

Background and aim:The purpose of the study was to compare the data obtained by two independent observers and statistically analyse the results using Cohen’s K to highlight the concordance or discordance in the diagnosis of normality, pathology and, in particular, the type of femoroacetabular impingement (FAI) on plain films.Methods:the study was conducted retrospectively. The only inclusion criterium was the minimum age of 20 years. All patients underwent a radiographic examination of the pelvis in standard anteroposterior projection in orthostasis.Results:A hundred patients were evaluated. A good concordance between the two operators in the examination of normal hip joint (k= 0.68 right/ 0,74 left) was found; a similar grade of agreement was found for the analysis of “pincer” type FAI (k = 0.73 right, 0,67 left). The best results in concordance were achieved in the examination of “cam” type FAI (k= 0.82 right, 0,88 left), “mixed” type FAI (k = 0.85 right, 0,86 left), and in findings of “coxa profunda” (k = 0.92 right, 0,88 left).Conclusion:We found a good concordance between the two readers; a few cases of disagreement were found in the diagnosis of “pincer” type FAI and absence of disease. This discrepancy may be due to the different weight given by the single observer to the clinical indication that leads the patient to examination, but also by the difficulty of a not dedicated radiologist to show some subtle signs indicative of early FAI.

Incidence of radiographic findings of femoroacetabular impingement in a healthy Egyptian population: a cross-sectional study

Background: Femoroacetabular impingement (FAI) is a unique pathological problem affecting young adults. It can be defined as the impingement between the proximal femur and the acetabular rim. Although clinical presentation usually is hip pain, it can be asymptomatic. Radiographic FAI findings are quite common in a population of healthy young adults and must be correlated to the clinical presentation. The aim of our study was to evaluate the incidence of radiographic findings of FAI among a cohort of healthy Egyptian participants. Methods: From March 2017 to April 2019, a cross-sectional study was conducted among a cohort of 160 Egyptians (100 men and 60 women) from 20 to 40 yr old. Anteroposterior and frog-leg lateral views were obtained for 320 hips. By using computer software (ICONICO Screen Protractor, ICONICO, Inc., New York, NY), we measured central edge crossover sign alpha angle and the acetabular index. Results: Pincer type FAI was found in 86 hips on the right side (53.27%) and in 104 hips on the left side (65%). Cam type of FAI was found in 54 hips on the right side (34.2%) and in 54 hips on the left side (34.2%). Mixed type was found in 26 hips on the right side (16.25%) and in 32 hips on the left side (20%). Conclusions: Radiographic FAI findings are quite common in Egyptian healthy young adults who have no hip symptoms. Clinical diagnosis is necessary for FAI and must be correlated with the radiographic data. Level of Evidence: Level II.

FUNCTIONAL OUTCOMES OF ARTHROSCOPIC TREATMENT IN 230 FEMOROACETABULAR IMPINGEMENT CASES.

ABSTRACTObjective: To analyze the functional outcomes after arthroscopic treatment of femoroacetabular impingement (FAI). Methods: 194 patients (131 males and 63 females), with a mean age of 39 (15-68) years old for men and 43 (16-58) years old for women. The average follow-up was 17 months (2 to 71). 103 patients presented Cam-type FAI, 102 mixed and 25 Pincer. “Unilateral” arthroscopy was performed in 161 cases, “Bilateral” (only once each side) in 46 cases and, “Multiple” (more than one procedure on the same hip) in 23. The female sex was prevalent in the Pincer type FAI (76%), while males were prevalent in Mixed and Cam type, 74.5% and 72.8%, respectively. Results: The mean HHSpre score was 63.7 and 87.1 for HHSpost, i.e. 73.11%. Differences appeared between “mixed” and “unilateral” groups. The complications percentage in this series was 18.7% and 7% progressed to total hip arthroplasty. Conclusion: The arthroscopic FAI treatment improved the postoperative clinical scores of these patients, especially in cases of mixed-type FAI, which presented a higher improvement rate. Insufficient femoral osteoplasty was the main cause for surgical re-intervention, particularly in the initial cases of this series. Level of Evidence II, Retrospective study.

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

Population-based prevalence of femoroacetabular impingement in Japan

Objectives The prevalence of femoroacetabular impingement (FAI) was evaluated using a Japanese population-based cohort of participants aged ≥50 years. Methods Radiographs (n = 854) of bilateral hips of 427 participants (279 women, 148 men) were used for the analysis. The prevalence of cam type, pincer type, and mixed type FAI as well as osteoarthritis was evaluated. The association of FAI and osteoarthritis (OA), and pain were also evaluated. Results The prevalence of cam type and pincer type FAI were 4.2% and 20.3%, respectively. Mixed type FAI was 0.7%. OA was found in 4.0% of patients, and 17 hips (2.0%) with any FAI also had OA. A significant relationship between cam type FAI and OA was found, whereas no significant relationship between pincer type FAI and OA was seen. Sixty (7.0%) of all the hips were reported to be painful, and 14 of those painful hips (1.6%) had FAI. No significant relationship between FAI and hip pain was found. Conclusion We reported the first population-based prevalence of FAI in Japan. Radiological FAI was common, and pincer type was more common than cam type. The anatomical abnormalities associated with FAI, although often asymptomatic, are risk factors for OA.