Symptomatic Femoroacetabular Impingement Research Articles

Six-Month Outcome Scores Predicts Short-Term Outcomes After Hip Arthroscopy

To determine whether early patient-reported outcome improvements in the 6 months after surgery are predictive of achieving a patient acceptable symptomatic state (PASS) at 2 years. A prospectively collected database was retrospectively reviewed. Inclusion criteria included patients ≥18 years of age, Tönnis grade 0 or 1 changes, radiographic imaging consistent with femoroacetabular impingement or labral pathology, a primary diagnosis of symptomatic femoroacetabular impingement for which they underwent primary hip arthroscopy, and baseline, 6-month, and 2-year modified Harris Hip Score (mHHS) scores. Revision cases were excluded. Receiver operating characteristic curve analysis was conducted to determine whether 6-month change in mHHS was a predictor for achieving PASS at 2 years. There were 173 patients (mean age: 39.8, 61.8% female) included within the study. Patients who do not achieve the minimal clinically important difference (MCID), defined as a change of 8 points in mHHS, by 6 months (n= 21) tended to have significantly lower mHHS scores at 1 year and 2 years compared with those who did (n= 152). Only 52% of patients who did not achieve MCID by 6 months achieved MCID by 2 years (vs 98% for those that did) and only 24% achieved PASS by 2 years (vs 88% that did). Using the MCID as a cutoff for improvement in mHHS at 6 months results in a 96% sensitivity but 47% specificity for predicting PASS achievement at 2 years. Using 24 points of improvement in mHHS as a cutoff at 6 months improves sensitivity and specificity to 81% and 80%, respectively. Early improvement in mHHS scores is associated with 2-year outcomes. Patients who do not achieve MCID within 6 months of surgery have a high rate of not achieving PASS at 2 years. IV, case series study.

Labral Index—Controlling Femoral Size to Evaluate the Relationship Between Relative Labral Size and Acetabular Version

PurposeTo assess the relationship of acetabular version with the length of the anterior and posterior labrum and to introduce a developed metric, the labral index, as a means of controlling for femoral head size when measuring labral length.MethodsOne hundred forty-eight patients who underwent hip arthroscopies for femoroacetabular impingement from October 2017 to October 2019 by a single hip surgeon were retrospectively reviewed. Magnetic resonance imaging arthrogram was used to measure central acetabular version (at the center of the femoral head) and cranial acetabular version (at the midpoint between the acetabular roof and center of the femoral head), as well as labral length at the anterior, posterior, and superolateral locations (3, 9, and 12 o’clock, respectively). Labral index was calculated by dividing anterior, posterior, and superolateral labral lengths by the radius of the femoral head. Pearson correlation analysis was used to assess the association between the 2 continuous variables. A priori alpha of 0.05 was established as the cutoff for significance.ResultsForty-three patients (26 female, 17 male) with an average age of 34.2 ± 11.6 years were included in analysis. Increased central anteversion was significantly associated with a larger anterior labral length and index (P = .023, r = 0.343 and .005, r = 0.415, respectively). Cranial anteversion weakly correlated with a significantly increased anterior labral index (P = .047, r = 0.304) but not with larger anterior labral length (P = .089, r = 0.262). No statistically significant association was present for central or cranial version with posterior or superolateral labral measurements. Lateral center edge angle did not correlate with labral size at any location.ConclusionsIn patients undergoing hip arthroscopy for symptomatic femoroacetabular impingement, greater acetabular anteversion was significantly associated but weakly correlated with increased anterior labral length, whereas no association was found between posterior labral length and acetabular version. The labral index may be a useful metric to normalize labral length relative to the radius of the femoral head that warrants further investigation for its clinical utility in guiding labral reconstruction versus labral repair.Level of EvidenceLevel IV, diagnostic case series.

Biochemical MRI With dGEMRIC Corresponds to 3D-CT Based Impingement Location for Detection of Acetabular Cartilage Damage in FAI Patients.

Background:Anterior femoroacetabular impingement (FAI) is associated with labral tears and acetabular cartilage damage in athletic and young patients. Delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) is an imaging method for detecting early damage to cartilage.Purpose:We evaluated the following questions: (1) What is the sensitivity and specificity of morphological magnetic resonance imaging (MRI) and dGEMRIC for detecting cartilage damage? Do the mean acetabular and femoral dGEMRIC indices differ between (2) superior acetabular clock positions with and without impingement and (3) between cam- and pincer-type FAI?Study Design:Cohort study (diagnosis); Level of evidence, 2.Methods:This was a retrospective comparative study of 21 hips (20 patients with symptomatic anterior FAI) without osteoarthritis on anteroposterior radiographs. Morphological MRI and dGEMRIC (3.0-T, 3-dimensional [3D] T1 maps, dual–flip angle technique) of the same hip joint were compared. Intraoperative acetabular cartilage damage was assessed in patients who underwent surgical treatment. Computed tomography (CT)–based 3D bone models of the same hip joint were used as the gold standard for the detection of impingement, and dGEMRIC indices and zones of morphologic damage were compared with the CT-based impingement zones.Results:Of the 21 hips, 10 had cam-type FAI and 8 had pincer-type FAI according to radiographs. The mean age was 30 ± 9 years (range, 17-48 years), 71% were female, and surgical treatment was performed in 52%. We found a significantly higher sensitivity (69%) for dGEMRIC compared with morphological MRI (42%) in the detection of cartilage damage (P < .001). The specificity of dGEMRIC was 83% and accuracy was 78%. The mean peripheral acetabular and femoral dGEMRIC indices for clock positions with impingement (485 ± 141 and 440 ± 121 ms) were significantly lower compared with clock positions without impingement (596 ± 183 and 534 ± 129 ms) (P < .001). Hips with cam-type FAI had significantly lower acetabular dGEMRIC indices compared with hips with pincer-type FAI on the anterosuperior clock positions (1 to 3 o’clock) (P = .018).Conclusion:MRI with dGEMRIC was more sensitive than morphological MRI, and lower dGEMRIC values were found for clock positions with impingement as detected on 3D-CT. This could aid in patient-specific diagnosis of FAI, preoperative patient selection, and surgical decision making to identify patients with cartilage damage who are at risk for inferior outcomes after hip arthroscopy.

Characteristics of hip impingement syndrome in patients with multiple hereditary exostoses

BackgroundsThis study aimed to investigate the characteristic deformities of the hip in multiple hereditary exostoses patients (MHE) and its association with the hip impingement syndrome.Materials and methodsBetween 2001 and 2019, total 51 patients (102 hips) were evaluated in this study. Patients with MHE were classified to femoro-acetabular impingement (FAI) symptom group, ischio-femoral impingement (IFI) symptom group and non-impingement symptom group by comparing the symptoms, clinical signs and imaging studies. To assess the morphometry of the hip in patients with MHE, the femoral neck-shaft angle, Sharp’s acetabular angle and center-edge (CE) angle were evaluated. Alpha angle was further evaluated to investigate the FAI using radiographs, and the minimum ischio-femoral distance was further measured to investigate the IFI using computed-tomographic (CT) study.ResultsOn hip impingement symptom analysis, FAI symptom and IFI symptom were confirmed in 14 hip joints and 18 hip joints, respectively. Unlike general population, the number of the hip with IFI-symptom was higher than those with FAI symptom in this study. In morphometric evaluation of MHE hips, coxa valga was most prominent deformity with occasional tendency of mild acetabular dysplasia. In a comparison of morphometric study between the impingement symptom group and non-symptom group, the FAI symptom showed significant differences of morphometric measure values than those of the non-symptom group (FAI symptom group vs. Non-FAI symptom group; Femoral neck-shaft angle (153.9 vs 142.6), Sharp’s angle (45.0 vs 41.5), CE angle (21.1 vs 28.8) and alpha angle (76.7 vs 57.9)). Similarly, the IFI symptom group also showed significant differences of morphometric measure values than those of the non-symptom group (IFI-symptom vs. Non-IFI symptom; Femoral neck-shaft angle (150.9 vs 142.7), Sharp’s angle (44.7 vs 41.4), CE angle (21.1 vs 29.3) and alpha angle (73.3 vs 56.8)). In addition, the minimum ischio-femoral distance measured using CT was significantly decreased in the IFI symptom group (IFI symptom group: 6.6, Non-IFI symptom group: 16.4).ConclusionThe results suggest that the characteristic deformities represented by coxa valga in the MHE hip act as an offset for FAI symptoms, on the contrary, act as a trigger for IFI symptoms.Level of evidenceLevel III.

CORR Insights®: Does the Capital Femoral Physis Bony Morphology Differ in Children with Symptomatic Cam-type Femoroacetabular Impingement.

CORR Insights®: Does the Capital Femoral Physis Bony Morphology Differ in Children with Symptomatic Cam-type Femoroacetabular Impingement.

Sex Differences in Clinical Outcomes Following Surgical Treatment of Femoroacetabular Impingement.

Sex-based differences in clinical outcomes following surgical treatment of femoroacetabular impingement remain largely uncharacterized; this prospective, multicenter study evaluated these differences both directly and adjusted for covariates. Hips undergoing surgical treatment of symptomatic femoroacetabular impingement were prospectively enrolled in a multicenter cohort. Patient demographics, radiographic parameters, intraoperatively assessed disease severity, and history of surgical procedures, as well as patient-reported outcome measures, were collected preoperatively and at a mean follow-up of 4.3 years. A total of 621 (81.6%) of 761 enrolled hips met the minimum 1 year of follow-up and were included in the analysis; 56.7% of analyzed hips were female. Univariate and multivariable statistics were utilized to assess the direct and adjusted differences in outcomes, respectively. Male hips had greater body mass index and larger α angles. Female hips had significantly lower preoperative and postoperative scores across most patient-reported outcome measures, but also had greater improvement from preoperatively to postoperatively. The preoperative differences between sexes exceeded the threshold for the minimal clinically important difference of the modified Harris hip score (mHHS) and all Hip disability and Osteoarthritis Outcome Score (HOOS) domains except quality of life. Preoperative sex differences in mHHS, all HOOS domains, and Short Form-12 Health Survey physical function component score were greater than the postoperative differences. A greater proportion of female hips achieved the minimal clinically important difference for the mHHS, but male hips were more likely to meet the patient acceptable symptom state for this outcome. After adjusting for relevant covariates with use of multiple regression analysis, sex was not identified as an independent predictor of any outcome. Preoperative patient-reported outcome scores were a strong and highly significant predictor of all outcomes. Significant differences in clinical outcomes were observed between sexes in a large cohort of hips undergoing surgical treatment of femoroacetabular impingement. Despite female hips exhibiting lower baseline scores, sex was not an independent predictor of outcome or reoperation. Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Choice of surgical treatment for slipped capital femoral epiphysis with severe chronic displacement of the epiphysis

Background. The spatial relationship between the epiphysis and the acetabulum in slipped capital femoral epiphysis (SCFE) with severe chronic epiphysis displacement is restored by different corrective extra-articular femoral osteotomies and a standard Dunn procedure. Severe residual deformity of the femoral component of the joint with symptoms of femoroacetabular impingement and a large number of severe ischemic complications forced the surgeons to improve the technique of these surgical interventions. In particular, a modified Dunn procedure was proposed using a low traumatic surgical hip dislocation. However, the selection of surgical treatment in these patients remains a subject of discussion.&#x0D; Aim. This study aimed to improve the results of treatment in children with SCFE with severe chronic epiphysis displacement.&#x0D; Materials and methods. Data of preoperative and postoperative clinical and radiological studies of 40 patients (24 male and 16 female) aged 1215 years who were suffering from SCFE with severe chronic epiphysis displacement were analyzed. In all cases, on the lesion side, displacement was found in typical directions (posterior-downward or only posterior), and in the contralateral joint, the disease was still at its initial stage (pre-slip). In group 1 (n = 20 children), a corrective extra-articular femoral (anterior-rotational or rotational-valgus) osteotomy was performed according to the method we have proposed in 2011 [22], and in group 2 (n = 20 children), the modified Dunn procedure that strictly followed our technique was performed. The follow-up period after surgery in both groups ranged from 1 month to 2.5 years.&#x0D; Results. At 2.5 years after surgery, good anatomical and functional outcomes were observed only in 1 (12.5%) of 8 patients in group 1, while they were observed in 7 (87.5%) of 8 patients in group 2. Poor results were determined by residual epiphyseal displacement (from 22 to 28) and/or step-like transition of the anterior femoral neck surface to the head in 5 (62.5%) children in group 1 and by femoral head avascular necrosis (diagnosed in 6 months after surgery) in 1 (12.5%) child in group 2.&#x0D; Conclusion. The results allow us to make a preliminary conclusion about the high efficiency of the modified Dunn procedure and the low efficiency of the corrective extra-articular femoral osteotomy in SCFE with severe chronic displacement of the epiphysis. The modified Dunn procedure corrects the pronounced deformity of the femoral component of the affected joint and femoroacetabular impingement in the above-mentioned anatomical situations.

Surgical Treatment of Femoroacetabular Impingement: Minimum 10-Year Outcome and Risk Factors for Failure.

Background:Femoroacetabular impingement (FAI) is a well-known cause of hip pain and dysfunction in young adults. Surgical treatment has been widely popularized during the past decade. However, most reported results have been limited to short-term and intermediate-term follow-up. The long-term success rate and risk factors for failure are largely unknown. This study aimed to report the long-term (minimum, 10 years) clinical outcomes of surgical treatment of FAI and to describe the clinical and radiographic parameters associated with the failure of treatment involving femoroacetabular osteoplasty (FAO) and labral repair.Methods:Using our prospective hip preservation database, 164 patients (178 hips) who had undergone FAO between January 2005 and April 2009 were identified. Patient demographic characteristics, clinical history, duration of preoperative symptoms, radiographic parameters (preoperative and postoperative alpha angles, hip dysplasia and retroversion, Tönnis grade for osteoarthritis), and intraoperative findings were reviewed and compared between the success and failure groups. At a minimum 10-year follow-up, clinical functional outcomes (modified Harris hip score [mHHS] and Short Form-36 [SF-36] at 6 weeks, 6 months, 1 year, and 10 years) and failure rates (conversion to total hip arthroplasty [THA]) were collected.Results:The mean patient age (and standard deviation) was 34.3 ± 8.4 years, and 65 patients (40%) were female. After the surgical procedure, there was significant improvement in the mean mHHS (59.3 ± 7.3 points preoperatively to 88.4 ± 7.3 points postoperatively) and the mean SF-36 (61.3 ± 8.4 points preoperatively to 89.1 ± 7.2 points postoperatively). At a mean follow-up of 12.5 years, 12% (22 hips) required conversion to THA, with a mean time to THA of 5.3 ± 2.0 years. Older age, longer preoperative symptomatic period, higher preoperative and postoperative alpha angles, presence of hip dysplasia, a higher Tönnis grade, joint space narrowing, and a full-thickness acetabular chondral lesion at the time of the FAO were identified as risk factors for failure and conversion to THA.Conclusions:Patients with symptomatic FAI who undergo a surgical procedure experience pain relief and functional improvement that appear to endure over a decade in the majority of patients. This study on a relatively large cohort with a long-term follow-up has also identified patients who are at a higher risk for treatment failure.Level of Evidence:Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Die Epiphysenfuge – Epiphysiolysis capitis femoris

During puberty, when growth accelerates, physis are weak and at risk for slippage. The slipped capital femoral epiphysis is often misdiagnosed. It should be considered even if the patient’s symptoms are not typical. The diagnosis can usually be made on conventional x-rays in two planes. The goal of therapy is to prevent further slippage and, if necessary, to achieve reduction. Depending on the severity, different surgical methods may be used. Patients should be followed for years after surgery. Femoro-acetabular impingement symptoms may develop, which require treatment.

Nonsurgical Versus Surgical Management of Femoroacetabular Impingement: What Does the Current Best Evidence Tell Us.

Controversy exists as to the management of femoroacetabular impingement (FAI). When nonsurgical management of symptomatic FAI fails, surgical management is generally indicated. However, many groups with a stake in patient care (particularly payors) have insisted on higher levels of evidence. Recently, there have been several Level I studies published, comparing physical therapy (PT) with hip arthroscopy in the management of symptomatic FAI. All of these studies have used outcomes tools developed and validated for patients with nonarthritic hip pain (the International Hip Outcome Tool). Most highest level evidence confirms that although patients with FAI do benefit from PT, patients who undergo surgical management for FAI with hip arthroscopy benefit more than those who undergo PT (mean difference in the International Hip Outcome Tool 6.8 [minimal clinically important difference 6.1], P = 0.0093). Future large prospective studies are needed to evaluate the effect on the outcomes when there is a delay in surgical management in symptomatic individuals, assess whether FAI surgery prevents or delays osteoarthritis, and determine the role of other advanced surgical techniques.

Does the Capital Femoral Physis Bony MorphologyDiffer in Children with Symptomatic Cam-type Femoroacetabular Impingement.

The epiphyseal tubercle, the corresponding metaphyseal fossa, and peripheral cupping are key stabilizers of the femoral head-neck junction. Abnormal development of these features in the setting of supraphysiologic physeal stress under high forces (for example, forces that occur during sports activity) may result in a cam morphology. Although most previous studies on cam-type femoroacetabular impingement (FAI) have mainly focused on overgrowth of the peripheral cupping, little is known about detailed morphologic changes of the epiphyseal and metaphyseal bony surfaces in patients with cam morphology. (1) Does the CT-based bony morphology of the peripheral epiphyseal cupping differ between patients with a cam-type morphology and asymptomatic controls (individuals who did not have hip pain)? (2) Does the CT-based bony morphology of the epiphyseal tubercle differ between patients with a cam-type morphology and asymptomatic controls? (3) Does the CT-based bony morphology of the metaphyseal fossa differ between patients with a cam-type morphology and asymptomatic controls? After obtaining institutional review board approval for this study, we retrospectively searched our institutional database for patients aged 8 to 15 years with a diagnosis of an idiopathic cam morphology who underwent a preoperative CT evaluation of the affected hip between 2005 and 2018 (n = 152). We excluded 96 patients with unavailable CT scans and 40 patients with prior joint diseases other than cam-type FAI. Our search resulted in 16 patients, including nine males. Six of 16 patients had a diagnosis of bilateral FAI, for whom we randomly selected one side for the analysis. Three-dimensional (3-D) models of the proximal femur were generated to quantify the size of the peripheral cupping (peripheral growth of the epiphysis around the metaphysis), epiphyseal tubercle (a beak-like prominence in the posterosuperior aspect of the epiphysis), and metaphyseal fossa (a groove on the metaphyseal surface corresponding to the epiphyseal tubercle). A general linear model was used to compare the quantified anatomic features between the FAI cohort and 80 asymptomatic hips (aged 8 to 15 years; 50% male) after adjusting for age and sex. A secondary analysis using the Wilcoxon matched-pairs signed rank test was performed to assess side-to-side differences in quantified morphological features in 10 patients with unilateral FAI. After adjusting for age and sex, we found that patients with FAI had larger peripheral cupping in the anterior, posterior, superior, and inferior regions than control patients who did not have hip symptoms or radiographic signs of FAI (by 1.3- to 1.7-fold; p < 0.01 for all comparisons). The epiphyseal tubercle height and length were smaller in patients with FAI than in controls (by 0.3- to 0.6-fold; p < 0.02 for all comparisons). There was no difference in tubercle width between the groups. Metaphyseal fossa depth, width, and length were larger in patients with FAI than in controls (by 1.8- to 2.3-fold; p < 0.001 for all comparisons). For patients with unilateral FAI, we saw similar peripheral cupping but smaller epiphyseal tubercle (height and length) along with larger metaphyseal fossa (depth) in the FAI side compared with the uninvolved contralateral side. Consistent with prior studies, we observed more peripheral cupping in patients with cam-type FAI than control patients without hip symptoms or radiographic signs of FAI. Interestingly, the epiphyseal tubercle height and length were smaller and the metaphyseal fossa was larger in hips with cam-type FAI, suggesting varying inner bone surface morphology of the growth plate. The docking mechanism between the epiphyseal tubercle and the metaphyseal fossa is important for epiphyseal stability, particularly at early ages when the peripheral cupping is not fully developed. An underdeveloped tubercle and a large fossa could be associated with a reduction in stability, while excessive peripheral cupping growth would be a factor related to improved physeal stability. This is further supported by observed side-to-side differences in tubercle and fossa morphology in patients with unilateral FAI. Further longitudinal studies would be worthwhile to study the causality and compensatory mechanisms related to epiphyseal and metaphyseal bony morphology in pathogenesis cam-type FAI. Such information will lay the foundation for developing imaging biomarkers to predict the risk of FAI or to monitor its progress, which are critical in clinical care planning. Level III, prognostic study.

Arthroscopy versus nonoperative treatment of symptomatic femoroacetabular impingement syndrome: A systematic review and meta-analysis.

Background:Presently, hip arthroscopy is a widely adopted surgical intervention for the treatment of femoroacetabular impingement (FAI). However, there is insufficient evidence regarding which between arthroscopy and nonoperative treatment is more optimal for symptomatic FAI.Methods:MEDLINE, Embase, Web of Science, and the Cochrane Library were systematically searched for studies that compared arthroscopy and nonoperative interventions for FAI treatment from inception to August 4, 2020. We included studies that directly compared surgical and nonsurgical treatment for symptomatic FAI and excluded those that did not use arthroscopic treatment as a surgical technique and studies performed on patients with concomitant diagnoses instead of pure FAI. We compared the following clinical outcome scores at 6 and 12 months of follow-up: International Hip Outcome Tool 33 (iHOT-33), hip outcome score (HOS), EuroQol-visual analog scale (EQ-VAS), modified Harris hip score (mHHS), and nonarthritic hip score (NAHS).Results:Five studies totaling 838 patients were included in the qualitative and quantitative synthesis; 382 patients underwent hip arthroscopy, and 456 patients were treated by nonoperative interventions. At 6 months of follow-up, there were no statistically significant differences in iHOT-33 ratings (mean difference [MD] = 7.92, P = .15), HOS (MD of HOS-ADL = 5.15, P = .26 and MD of HOS-Sports = 2.65, P = .79, respectively), and EQ-VAS (MD = 1.22, P = .76) between the 2 treatment strategies. At 12 months of follow-up, the arthroscopy group had a greater mean improvement in iHOT-33 score than the conservative treatment group (MD = 8.42, P = .002), but there was no difference between the groups in terms of mHHS rating (MD = −0.24, P = .83) and NAHS (MD = −2.08, P = .09).Conclusion:Despite arthroscopy being associated with significantly superior iHOT-33 scores after 12 months of follow-up, we were unable to discern the difference between the treatment strategies using other scoring methods, such as HOS, EQ-VAS, mHHS, and NAHS. Further studies will be needed to conclusively determine if 1 strategy is superior to the other for treating FAI.

Prevalence of combined abnormalities of tibial and femoral torsion in patients with symptomatic hip dysplasia and femoroacetabular impingement.

The prevalence of combined abnormalities of femoral torsion (FT) and tibial torsion (TT) is unknown in patients with femoroacetabular impingement (FAI) and hip dysplasia. This study aimed to determine the prevalence of combined abnormalities of FT and TT, and which subgroups are associated with combined abnormalities of FT and TT. We retrospectively evaluated symptomatic patients with FAI or hip dysplasia with CT scans performed between September 2011 and September 2016. A total of 261 hips (174 patients) had a measurement of FT and TT. Their mean age was 31 years (SD 9), and 63% were female (165 hips). Patients were compared to an asymptomatic control group (48 hips, 27 patients) who had CT scans including femur and tibia available for analysis, which had been acquired for nonorthopaedic reasons. Comparisons were conducted using analysis of variance with Bonferroni correction. In the overall study group, abnormal FT was present in 62% (163 hips). Abnormal TT was present in 42% (109 hips). Normal FT combined with normal TT was present in 21% (55 hips). The most frequent abnormal combination was increased FT combined with normal TT of 32% (84 hips). In the hip dysplasia group, 21% (11 hips) had increased FT combined with increased TT. The prevalence of abnormal FT varied significantly among the subgroups (p < 0.001). We found a significantly higher mean FT for hip dysplasia (31°; SD 15)° and valgus hips (42° (SD 12°)) compared with the control group (22° (SD 8°)). We found a significantly higher mean TT for hips with cam-type-FAI (34° (SD 6°)) and hip dysplasia (35° (SD 9°)) compared with the control group (28° (SD 8°)) (p < 0.001). Patients with FAI had a high prevalence of combined abnormalities of FT and TT. For hip dysplasia, we found a significantly higher mean FT and TT, while 21% of patients (11 hips) had combined increased TT and increased FT (combined torsional malalignment). This is important when planning hip preserving surgery such as periacetabular osteomy and femoral derotation osteotomy. Cite this article: Bone Joint J 2020;102-B(12):1636-1645.

A novel concept of cam-type femoroacetabular impingement treatment with patient-specific template guided osteochondral deformity ablation.

To present a novel surgical concept for the cam-type femoroacetabular impingement (FAI) treatment and to assess and report the clinical outcomes. We performed a retrospective study of a single-surgeon case series of six hips in five consecutive male patients with symptomatic cam-type FAI, treated with the mini-open anterior hip approach with a patient-specific template (PST)-guided deformity ablation between 2015 and 2018. We assessed the hip range of motion, iHOT-33, Tegner, and EQ-5D before surgery and after a minimum follow-up of 30months. The average age was 37 ± 13.3years, average BMI was 31.1 ± 3.3kg/m2, and average pre-surgery Tönnis hip osteoarthritis (OA) grade was 1 ± 1. The average surgery duration was 71 ± eightminutes. The average estimated blood loss was 83 ± 26ml. After a mean follow-up of 50 ± 12months, we observed no OA progression with no change in Tönnis hip OA grades. Hip flexion and internal rotation significantly improved (p = 0.007; p = 0.048) from mean 98° ± 9° and 14° ± 11° to mean 113° ± 8° and 23° ± 8°, respectively. iHOT-33, Tegner, and EQ-5D improved significantly (p = < 0.001; p = 0.004; p = < 0.001) from mean 44.7 ± 12.2, 3 ± 1, and 0.513420 ± 0.101389 to mean 94 ± 2.7, 5 ± 1, and 1.000000 ± 0, respectively. One patient needed revision surgery for heterotopic ossification removal, with no sequelae at the last follow-up. Mini-open anterior hip approach with the PST-guided cam-type FAI deformity ablation presents an accurate and reproducible solution for cam-type FAI surgical treatment, with promising clinical outcomes. Using a PST in the cam-type FAI surgery may present a powerful additional tool in the existing open techniques armamentarium.

Short-term Clinical Outcomes of Hip Arthroscopy Versus Physical Therapy in Patients With Femoroacetabular Impingement: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

Background:Both physical therapy (PT) and surgery are effective in treating femoroacetabular impingement (FAI), but their relative efficacy has not been well established until recently. Several randomized controlled trials (RCTs) comparing the early clinical outcomes of these treatments have been published, with contradictory results.Purpose/Hypothesis:The purpose of this study was to perform a meta-analysis of RCTs that compared early patient-reported outcomes (PROs) of hip arthroscopy versus PT in patients with symptomatic FAI. The hypothesis was that surgical treatment of FAI leads to better short-term outcomes than PT.Study Design:Systematic review; Level of evidence, 1.Methods:In March 2019, a systematic review was performed to identify RCTs comparing hip arthroscopy and PT in patients with symptomatic FAI. A total of 819 studies were found among 6 databases; of these, 3 RCTs met eligibility (Griffin et al, 2018; Mansell et al, 2018; and Palmer et al, 2019). All 3 RCTs reported international Hip Outcome Tool--33 (iHOT-33) scores, and 2 reported Hip Outcome Score (HOS)–Activities of Daily Living (ADL) and HOS-Sport results. In a random-effects meta-analysis, between-group differences in postintervention scores were assessed according to intention-to-treat and as-treated approaches. Quality was assessed with CONSORT, CERT, TiDieR, and the Cochrane Collaboration tool.Results:The 3 RCTs included 650 patients with FAI; the mean follow-up ranged from 8 to 24 months. All studies reported PRO improvement from baseline to follow-up for both PT and surgery. The quality of the Griffin and Palmer studies was good, with minimal bias. In the Mansell study, a 70% crossover rate from PT to surgery increased the risk of bias. The meta-analysis demonstrated improved iHOT-33 outcomes with surgery compared with PT for intention-to-treat (mean difference [MD], 11.3; P = .046) and as-treated (MD, 12.6; P = .007) analyses. The as-treated meta-analysis of HOS-ADL scores favored surgery (MD, 12.0; P < .001), whereas the intention-to-treat analysis demonstrated no significant difference between groups for HOS-ADL (MD, 3.9; P = .571).Conclusion:In patients with FAI, the combined results of 3 RCTs demonstrated superior short-term outcomes for surgery versus PT. However, PT did result in improved outcomes and did not appear to compromise the surgical outcomes of patients for whom therapy failed and who progressed to surgery.

Prevalence of Lumbosacral Transitional Vertebrae in Patients With Symptomatic Femoroacetabular Impingement Requiring Hip Arthroscopy

The primary aim of this study was to determine the prevalence of lumbosacral transitional vertebrae (LSTVs) in patients with symptomatic femoroacetabular impingement (FAI) requiring hip arthroscopy. The secondary aim was to determine whether there is an association between LSTV anatomy and patient-reported outcomes. This retrospective study included patients aged 18 to 45 years with symptomatic FAI who underwent arthroscopy between March 2010 and March 2016 and had anteroposterior pelvic radiographs. The exclusion criteria included lack of an FAI diagnosis, hip osteoarthritis (Tönnis grade ≥ 2), prior spinal fusion surgery, prior total hip arthroplasty, indications for total hip arthroplasty, and revision surgery on the affected hip. All radiographs were assessed by an interventional spine and sports fellow. The primary outcome was the prevalence of LSTVs, classified using the criteria of Castellvi etal. Secondary outcomes included the modified Harris Hip Score, Hip Outcome Score, and International Hip Outcome Tool 33 score. A total of 1,880 patients were included. Review of the patients' radiographs yielded 262 LSTVs, for an overall prevalence of 13.9% (type IA in 104 [5.5%], type IB in 53 [2.8%], type IIA in 60 [3.2%], type IIB in 25 [1.3%], type IIIA in 8 [0.4%], type IIIB in 0 [0%], and type IV in 12 [0.64%]). The prevalence of type II, III, and IV LSTVs was 5.6% (n=105). Unilateral LSTV sidedness did not correlate with symptom laterality (κ= 0.07). There were no differences in patient-reported outcomes between patients with LSTV anatomy and those without it. In this large cohort of 1,880 patients with symptomatic FAI, the prevalence of LSTVs was 13.9%. There was no correlation between sidedness of unilateral LSTVs and the symptomatic hip. Furthermore, there was no association between LSTV anatomy and patient-reported outcomes. The prevalence of LSTVs in this cohort was similar to the prevalence rates previously reported in patients with low-back pain. Level IV, case series.

Prospective Single-Blinded Randomized Controlled Trial Comparing Pericapsular Injection Versus Lumbar Plexus Peripheral Nerve Block for Hip Arthroscopy

Background: Hip arthroscopy has become the standard for the operative treatment of symptomatic femoroacetabular impingement. Given the high levels of postoperative pain associated with hip arthroscopy, optimal analgesia is critical to ensure patient comfort and safety after discharge. Purpose/Hypothesis: Our purpose was to perform a single-blinded randomized controlled trial comparing the use of pericapsular injection versus lumbar plexus blockade for postoperative pain control after arthroscopic surgery on the hip. We hypothesized that pericapsular injection would provide equivalent pain relief to that of lumbar plexus blockade while minimizing adverse effects and alleviating the dependence on a qualified individual to administer. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: A total of 64 consecutive patients undergoing hip arthroscopy were prospectively assessed over a 6-month period between 2017 and 2018. Patients were randomly allocated to 1 of 2 groups: 32 patients received a lumbar plexus blockade by a single anesthesiologist, while 32 patients received a pericapsular injection of 30 mL of ropivacaine and 12 mg of morphine. Postoperative pain in the postanesthesia care unit (PACU) as measured using the numeric rating scale, time to discharge, PACU morphine equivalents, and adverse effects were collected by PACU staff. Postoperative day 1 and 2 narcotic use was obtained through a telephone call with the patient on postoperative day 3. Results: We found no statistically significant difference in PACU pain scores at all time points, although there was a trend toward lower pain for patients receiving a pericapsular injection. PACU and short-term narcotic demand did not vary across the 2 arms. Time to discharge from the PACU did not differ. There were no major adverse events reported for either intervention. Conclusion: Pericapsular injection provides equivalent analgesia when compared with lumbar plexus blockade. It is a safe intervention that allows for efficient postoperative analgesia for patients undergoing hip arthroscopy. Registration: ClinicalTrials.gov ID: NCT03244631.

Distinct Pattern of Inflammation of Articular Cartilage and the Synovium in Early and Late Hip Femoroacetabular Impingement

Background: The molecular mechanism of how femoroacetabular impingement (FAI) morphology leads to hip osteoarthritis (OA) is yet to be determined. The expression and location of inflammation-related molecules during early- and late-stage FAI have not been previously described. Moreover, the characterization of intra-articular inflammation away from the cam deformity as well as the nature of adjacent synovial tissue have also not been extensively reported. Hypothesis: Early-stage FAI has a similar expression of inflammation-related markers in the head-neck and acetabular cartilage but less synovitis than late-stage FAI. Study Design: Controlled laboratory study. Methods: Head-neck cartilage, acetabular cartilage, and synovial samples were obtained from patients undergoing hip preservation surgery for the treatment of symptomatic cam FAI (early FAI group; n = 15) and advanced OA secondary to cam FAI (late FAI group; n = 15). Samples procured from healthy young adult donors served as the control group (n = 7). Cartilage degeneration was assessed by histology, and the expression of inflammation-related proteins (interleukin–1 beta [IL-1β], matrix metalloproteinase–13 [MMP-13], a disintegrin and metalloproteinase with thrombospondin motifs–4 [ADAMTS-4], type II collagen [COL2], and aggrecan neoepitope [NITEGE]) was measured by immunostaining. Synovial samples in the early and late FAI groups were examined for synovitis and the expression of IL-1β. Results: Head-neck cartilage in the early FAI group showed significantly more degeneration than the control group and an increased expression of inflammation-related proteins (IL-1β: 69.7% ± 18.1% vs 20.2% ± 4.9%, respectively; MMP-13: 79.6% ± 12.6% vs 25.3% ± 9.5%; ADAMTS-4: 83.9% ± 12.2% vs 24.3% ± 11.1%; NITEGE: 89.7% ± 7.7% vs 39.8% ± 20.5%) (P < .001). Head-neck and acetabular cartilage in the early and late FAI groups showed a similar degree of degeneration. Moreover, a similar expression of inflammation-related proteins was observed between the early and late FAI groups for head-neck cartilage (IL-1β: 69.7% ± 18.1% vs 72.5% ± 13.2%; MMP-13: 79.6% ± 12.6% vs 71.4% ± 18.8%; ADAMTS-4: 83.9% ± 12.2% vs 82.6% ± 12.5%; COL2: 93.6% ± 3.9% vs 92.5% ± 5.8%; NITEGE: 89.7% ± 7.7% vs 95.7% ± 4.7%) and acetabular cartilage (IL-1β: 83.3% ± 24.8% vs 80.7% ± 15.6%; MMP-13: 94.3% ± 9.7% vs 85.2% ± 12.3%; ADAMTS-4: 98.5% ± 2.3% vs 98.4% ± 3.4%; COL2: 99.8% ± 0.7% vs 99.7% ± 1.1%; NITEGE: 96.7% ± 6.7% vs 99.2% ± 2.2%). In contrast, synovitis was minimal with a low expression of IL-1β in the early FAI group compared with the late FAI group. Conclusion: Hip cartilage exhibited an OA phenotype in patients with early-stage FAI, similar to what was observed in hip OA secondary to FAI. Severe synovitis was only evident with late-stage FAI. Clinical Relevance: This study supports the concept that early hip impingement is associated with cartilage degeneration and catabolism.

Importance of Retaining Sufficient Acetabular Depth: Successful 2-Year Outcomes of Hip Arthroscopy for Patients With Pincer Morphology as Compared With Matched Controls

Background: Patients with pincer-type femoroacetabular impingement are commonly treated with arthroscopic reduction of acetabular depth as measured by the lateral center-edge angle (LCEA). The optimal amount of rim reduction has not been established, although large resections may increase contact pressures through the hip. A recent publication demonstrated inferior surgical outcomes in patients with acetabular overcoverage as compared with normal acetabular coverage. Casual observation of our database suggested equivalent improvements, prompting a similar analysis. Purpose: To analyze patient-reported outcomes after hip arthroscopy for femoroacetabular impingement in patients with acetabular overcoverage who were matched with controls with normal coverage, as well as to analyze associations with reduction in LCEA. Study Design: Cohort study; Level of evidence, 3. Methods: Data were collected prospectively from patients with a minimum 2-year follow-up after receiving hip arthroscopy for femoroacetabular impingement by a single surgeon. Cases were reviewed to identify those with pincer-type morphology (LCEA >40°) and matched according to sex, age, chondral damage, and surgery date in a 1:1 ratio with controls with an LCEA of 25° to 40°. The surgical goal was to reduce the LCEA to the upper end of the normal range with minimal rim resection, usually 35° to 37°. Radiographic measurements of coverage, intraoperative findings, procedures, and patient-reported outcomes were recorded, including the 12-Item International Hip Outcome Tool, Non-arthritic Hip Score, Hip Disability and Osteoarthritis Outcome Score, visual analog scale for pain, rates of revision or reoperation, and conversion to total hip arthroplasty. Results: A total of 114 hips (93 patients) for the pincer group were matched 1:1 from 616 hips (541 patients) for the control group. The pincer group (mean ± SD age, 34.5 ± 12.2 years) did not differ in age, body mass index, or follow-up from controls. LCEA was reduced in both groups pre- to postoperatively: the pincer group from 44.0° ± 2.8° to 34.2° ± 3.5° and the controls from 32.9° ± 3.9° to 31.0° ± 3.0°. No differences in improvement were observed: iHOT-12 improved by 35.7 points in both groups (P = .9 for analysis of variance interaction) and Nonarthritic Hip Score by 22.3 points (P = .6). From all eligible surgical procedures, 2-year follow up rates were 2.5% and 2.6% for the pincer and control cohorts, respectively, and 1.2% and 0.3% for conversion to total hip arthroplasty. Conclusion: Arthroscopic management of acetabular overcoverage can achieve excellent results, equivalent to arthroscopy for other causes of symptomatic femoroacetabular impingement. A key finding was smaller rim resections producing a mean postoperative LCEA of 34.2° with a small standard deviation.

Improved Cartilage Quality on Delayed Gadolinium-Enhanced MRI of Hip Cartilage after Subchondral Drilling of Acetabular Cartilage Flaps in Femoroacetabular Impingement Surgery at Minimum 5-Year Follow-Up.

To assess whether subchondral drilling of acetabular cartilage flaps during femoroacetabular impingement (FAI) surgery improves (1) acetabular dGEMRIC indices and (2) morphologic magnetic resonance imaging (MRI) scores, compared with hips in which no additional treatment of cartilage lesions had been performed; and (3) whether global dGEMRIC indices and MRI scores correlate. Prospective cohort study of consecutive patients with symptomatic FAI treated with open surgery between 2000 and 2007. Patients with subchondral drilling of acetabular cartilage flaps were allocated to the study group, those without drilling to the control group. All patients underwent indirect 3-T MR arthrography to assess cartilage quality by dGEMRIC indices and a semiquantitative morphologic MRI score at minimum 5 years after surgery. dGEMRIC indices and morphologic MRI scores were compared between and among groups using analysis of covariance/paired t tests. No significant difference was found between the global dGEMRIC indices of the study group (449 ± 147 ms, 95% CI 432-466 ms) and the control group (428 ± 143 ms, 95% CI 416-442 ms; P = 0.235). In regions with cartilage flaps, the study group showed higher dGEMRIC indices (472 ± 160 ms, 95% CI 433-510 ms) compared with the control group (390 ± 122 ms, 95% CI 367-413 ms; P < 0.001). No significant differences were found for the morphologic MRI scores. A strong inversely linear correlation between the dGEMRIC indices and the morphologic MRI scores (r = -0.727, P < 0.001) was observed. Treatment of acetabular cartilage flaps with subchondral drilling leads to better cartilage quality in regions with cartilage flaps at minimum 5 years of follow-up.