Prevalência da morfologia de impacto femoroacetabular em jogadores de futebol juvenil assintomáticos: estudo de ressonância magnética com correlação clínica

Hip Preservation Surgery in Osteoarthritis Prevention: Potential Benefits of the Radiographic Angular Correction

Objective: The aim of the study is to describe the morphology associated with the development of osteoarthritis (OA) in three different age groups. These data will contribute to defining the morphology associated with early and late hip OA. Methods: We studied 400 hips in 377 patients who had undergone primary THA due to idiopathic OA. Three groups were compared: group 1 (n = 147), younger patients, aged up to 60 years; group 2 (n = 155), patients aged between 61 and 74 years; and group 3 (n = 98), aged 75 or over. Five independent researchers measured the hip angles and the mean values were used to build a database. Results: No differences between groups in sex distribution and BMI were detected. Less coverage of the head (extrusion index), higher Tönnis angle, lower Wiberg and alpha angles characterized early OA hips. These differences increased with age, being greater between group 2 and group 3 (p < 0.01). However, significant differences were still present in the comparison between group 1 and group 2 (p < 0.01)). No differences were detected between group 2 and group 3. Conclusion: Elevated acetabular angle, head extrusion and decreased Wiberg angle characterize hip osteoarthritis at younger ages and should be the focus of hip preservation surgery in terms of osteoarthritis prevention. Pincer-type FAI (higher Wiberg and lower Tönnis angle) and higher alpha angle (CAM) are correlated with the development of later OA. These results shed doubt on applying the hip preservation surgery concept in terms of osteoarthritis prevention in FAI, especially in Pincer-type FAI patients.

Does the Type of Sport Influence Morphology of the Hip? A Systematic Review

BACKGROUND

Femoroacetabular impingement (FAI) has been extensively investigated and is strongly associated with athletic participation.

PURPOSE

To assess (1) the prevalence of cam-type FAI across various sports; (2) whether kinematic variation among sports influences hip morphology; and (3) whether performance level, duration, and frequency of participation or other factors influence hip morphology in a sporting population.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic search of Embase, PubMed, and the Cochrane Library was undertaken following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Prospective and retrospective case series, case reports, and review articles published after 1999 were screened, and those that met the inclusion criteria decided a priori were included for analysis.

RESULTS

The literature search identified 58 relevant articles involving 5683 participants. A total of 49 articles described a higher prevalence of FAI across various "hip-heavy" sports, including soccer, basketball, baseball, ice hockey, skiing, golf, and ballet. In studies including nonathlete controls, a greater prevalence of FAI was reported in 66.7% of studies (n = 8/12). The highest alpha angle was identified at the 1-o'clock position (n = 9/9) in football, skiing, golf, ice hockey, and basketball. The maximum alpha angle was located in a more lateral position in goalkeepers versus positional players in ice hockey (1 vs 1:45 o'clock). A positive correlation was also identified between the alpha angle and both age and activity level (n = 5/8 and n = 2/3, respectively) and between prevalence of FAI and both age and activity level (n = 2/2 and n = 4/5).

CONCLUSION

Hip-heavy sports show an increased prevalence of FAI, with specific sporting activities influencing hip morphology. There is some evidence to suggest that a longer duration and higher level of training also result in an increased prevalence of FAI.

REGISTRATION

CRD4202018001 (PROSPERO).

Isolated Acetabuloplasty for Femoroacetabular Impingement: Favorable Patient-Reported Outcomes and Sustained Survivorship at Minimum 5-Year Follow-Up

PURPOSE

To evaluate minimum 5-year outcomes and conversion rate to total hip arthroplasty (THA) for the treatment of femoroacetabular impingement (FAI) syndrome with an isolated acetabular osteoplasty.

METHODS

Patients undergoing hip arthroscopy with an isolated acetabular osteoplasty from March 2009 to June 2014 for FAI syndrome with pincer and/or cam morphology and a labral tear were identified. Those who underwent femoroplasty or prior ipsilateral hip surgery or who had previous hip conditions, ipsilateral hip dysplasia, or a Tönnis grade higher than 2 were excluded. Patient-reported outcomes (PROs) collected included Patient-Reported Outcomes Measurement Information System (PROMIS) scores specific to physical functioning and pain interference, modified Harris Hip Score, International Hip Outcome Tool 12, Hip Outcome Score-Activities of Daily Living, Hip Outcome Score-Sport-Specific Subscale, and Numeric Pain Rating Scale. Patients were also queried about secondary surgical procedures and conversion to THA.

RESULTS

We identified 86 patients at minimum 5-year follow-up (average, 7.4 years). The average patient age was 39.8 ± 12.3 years, 70.9% of patients were female, and 7% of patients had Tönnis grade 2. The mean PRO scores were 52.0 ± 8.9 for the PROMIS physical functioning score, 39.6 ± 7.5 for the PROMIS pain interference score, 78.7 ± 12.0 for the modified Harris Hip Score, 73.3 ± 23.1 for the International Hip Outcome Tool 12 score, 89.9 ± 12.0 for the Hip Outcome Score-Activities of Daily Living, and 81.4 ± 21.0 for the Hip Outcome Score-Sport-Specific Subscale. Of the patients, 72.1% achieved the patient acceptable symptomatic state (PASS) according to previously established PASS scores for FAI syndrome treated with hip arthroscopy at minimum 5-year follow-up. The overall rate of revision arthroscopy was 3.5%, and the rate of conversion to THA was 5.8%.

CONCLUSIONS

An isolated acetabular osteoplasty can provide sustained clinical benefits for the treatment of FAI syndrome with labral tears, with good to excellent PROs and PASS rates and a low rate of conversion to THA at minimum 5-year follow-up.

LEVEL OF EVIDENCE

Level IV, case series.

Prevalence of Morphological Variations Associated With Femoroacetabular Impingement According to Age and Sex: A Study of 1878 Asymptomatic Hips in Nonprofessional Athletes

Background:

Radiographic findings related to the cam and pincer variants of femoroacetabular impingement (FAI) include measurements of the alpha angle and lateral center-edge angle (LCEA). The function of these radiographic findings has been put into question because of high heterogeneity in reported studies.

Purpose:

The aim of this study was 3-fold: (1) to determine the prevalence of cam and pincer variants according to sex and age on anteroposterior (AP) pelvic radiographs from an asymptomatic nonathletic population, (2) to identify the most common radiographic signs of cam- and pincer-type variants, and (3) to determine if there are variations in the prevalence of these radiographic signs according to sex and age.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

There were 3 independent observers who retrospectively analyzed the 939 AP pelvic radiographs (1878 hips) of patients aged 18 to 50 years who did not have hip symptoms and who were not professional athletes. The prevalence of the cam and pincer variants according to the alpha angle and LCEA, respectively, and the presence of other radiographic signs commonly associated with these variables were determined in the overall population and by subgroup according to sex and age group (18-30, 31-40, and 41-50 years). Descriptive and inferential statistics were used to analyze the study sample.

Results:

The mean age of the included population was 31.0 ± 9.2 years, and 68.2% were male. The prevalence of the cam-type variant was 29.7% (558/1878), and that of the pincer-type variant was 24.3% (456/1878). The radiographic signs that were most associated with the cam and pincer variants were a pistol-grip deformity and the crossover sign, respectively. Significant differences (P < .001) in the prevalence of these variants were identified between men and women in both variants. No differences were observed in the alpha angle or LCEA according to sex or age.

Conclusion:

Radiographic findings suggestive of FAI had significant variations with respect to sex and age in this study sample. This study provides information to determine the prevalence of these anatomic variants in the general population.

The prevalence of femoroacetabular impingement anatomy in Division 1 aquatic athletes who tread water

Femoroacetabular impingement (FAI) is a disorder that causes hip pain and disability in young patients, particularly athletes. Increased stress on the hip during development has been associated with increased risk of cam morphology. The specific forces involved are unclear, but may be due to continued rotational motion, like the eggbeater kick. The goal of this prospective cohort study was to use magnetic resonance imaging (MRI) to identify the prevalence of FAI anatomy in athletes who tread water and compare it to the literature on other sports. With university IRB approval, 20 Division 1 water polo players and synchronized swimmers (15 female, 5 male), ages 18-23 years (mean age 20.7 ± 1.4), completed the 33-item International Hip Outcome Tool and underwent non-contrast MRI scans of both hips using a 3 Tesla scanner. Recruitment was based on sport, with both symptomatic and asymptomatic individuals included. Cam and pincer morphology were identified. The Wilcoxon Signed-Rank/Rank Sum tests were used to assess outcomes. Seventy per cent (14/20) of subjects reported pain in their hips yet only 15% (3/20) sought clinical evaluation. Cam morphology was present in 67.5% (27/40) of hips, while 22.5% (9/40) demonstrated pincer morphology. The prevalence of cam morphology in water polo players and synchronized swimmers is greater than that reported for the general population and at a similar level as some other sports. From a clinical perspective, acknowledgment of the high prevalence of cam morphology in water polo players and synchronized swimmers should be considered when these athletes present with hip pain.

Does a Traumatic Etiology of Hip Pain Influence Hip Arthroscopy Outcomes?

PURPOSE

To determine whether patients who reported a discrete traumatic event precipitating the onset of femoroacetabular impingement syndrome (FAIS) reported similar patient-reported outcomes for the modified Harris Hip Score (mHHS) and the Non-Arthritic Hip Score (NAHS) following hip arthroscopy as patients with atraumatic hip pain associated with FAIS alone.

METHODS

A retrospective comparative therapeutic investigation of a prospectively collected database of cases performed by a single surgeon from 2010 to 2015 identified a group of patients who developed FAIS after a discrete traumatic event. This group was compared 1:2 with a body mass index and age-matched group of primary hip arthroscopies with atraumatic hip pain attributed to FAIS. Preoperative mHHS and NAHS were obtained and compared with those at 2-year follow-up. Clinical failure at 2 years was defined as any further ipsilateral hip surgery including revision arthroscopy and conversion to arthroplasty.

RESULTS

In the traumatic etiology group, the mean mHHS and NAHS improved from 49.6 to 82.7 (P < .001) and from 46.9 to 84.0 (P < .001), respectively. The mean mHHS and NAHS in the atraumatic group improved from 51.5 to 85.82 (P < .001) and from 49.3 to 85.2 (P < .001), respectively. Survivorship at 2 years was 81.1% for traumatic etiology and 88.3% for atraumatic etiology; adjusted proportional hazards regression analysis demonstrated a difference in survivorship that was not statistically significant between the traumatic and atraumatic cohorts (hazard ratio 1.8, 95% confidence interval 0.8-4.0).

CONCLUSIONS

The findings of this study demonstrate that patients presenting with FAIS and history of a traumatic hip injury can expect to experience similar good outcomes at 2 years following primary hip arthroscopy as compared with patients with atraumatic FAIS.

LEVEL OF EVIDENCE

Level III (Therapeutic) retrospective comparative study.

Evaluation of Osseous Morphology of the Hip Using Zero Echo Time Magnetic Resonance Imaging

BACKGROUND

Femoroacetabular impingement syndrome (FAIS) is a common disorder of the hip resulting in groin pain and ultimately osteoarthritis. Radiologic assessment of FAI morphologies, which may present with overlapping radiologic features of hip dysplasia, often requires the use of computed tomography (CT) for evaluation of osseous abnormality, owing to the difficulty of direct visualization of cortical and subchondral bone with conventional magnetic resonance imaging (MRI). The use of a zero echo time (ZTE) MRI pulse sequence may obviate the need for CT by rendering bone directly from MRI.

PURPOSE/HYPOTHESIS

The purpose was to explore the application of ZTE MRI to the assessment of osseous FAI and dysplasia morphologies of the hip. It was hypothesized that angular measurements from ZTE images would show significant agreement with measurements obtained from CT images.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 2.

METHODS

Thirty-eight hips from 23 patients were imaged with ZTE MRI and CT. Clinically relevant angular measurements of hip morphology were made in both modalities and compared to assess agreement. Measurements included coronal and sagittal center-edge angles, femoral neck-shaft angle, acetabular version (at 1-, 2-, and 3-o'clock positions), Tönnis angle, alpha angle, and modified-beta angle. Interrater agreement was assessed for a subset of 10 hips by 2 raters. Intermodal agreement was assessed on the complete cohort and a single rater.

RESULTS

Interrater agreement was demonstrated in both CT and ZTE, with intraclass correlation coefficient values ranging from 0.636 to 0.990 for ZTE and 0.747 to 0.983 for CT, indicating "good" to "excellent" agreement. Intermodal agreement was also shown to be significant, with intraclass correlation coefficients ranging from 0.618 to 0.904.

CONCLUSION

Significant agreement of angular measurements for hip morphology exists between ZTE MRI and CT imaging. ZTE MRI may be an effective method to quantitatively evaluate osseous hip morphology.

Hip Joint Torsional Loading Before and After Cam Femoroacetabular Impingement Surgery

BACKGROUND

Surgical management of cam femoroacetabular impingement (FAI) aims to preserve the native hip and restore joint function, although it is unclear how the capsulotomy, cam deformity, and capsular repair influence joint mechanics to balance functional mobility.

PURPOSE

To examine the contributions of the capsule and cam deformity to hip joint mechanics. Using in vitro, cadaveric methods, we examined the individual effects of the surgical capsulotomy, cam resection, and capsular repair on passive range of motion and resistance of applied torque.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Twelve cadaveric hips with cam deformities were skeletonized to the capsule and mounted onto a robotic testing platform. The robot positioned each intact hip in multiple testing positions: (1) extension, (2) neutral 0°, (3) flexion 30°, (4) flexion 90°, (5) flexion-adduction and internal rotation (FADIR), and (6) flexion-abduction and external rotation. Then the robot performed applicable internal and external rotations, recording the neutral path of motion until a 5-N·m of torque was reached in each rotational direction. Each hip then underwent a series of surgical stages (T-capsulotomy, cam resection, capsular repair) and was retested to reach 5 N·m of internal and external torque again after each stage. During the capsulotomy and cam resection stages, the initial intact hip's recorded path of motion was replayed to measure changes in resisted torque.

RESULTS

Regarding changes in motion, external rotation increased substantially after capsulotomies, but internal rotation only further increased at flexion 90° (change +32%, P = .001, d = 0.58) and FADIR (change +33%, P < .001, d = 0.51) after cam resections. Capsular repair provided marginal restraint for internal rotation but restrained the external rotation compared with the capsulotomy stage. Regarding changes in torque, both internal and external torque resistance decreased after capsulotomy. Compared with the capsulotomy stage, cam resection further reduced internal torque resistance during flexion 90° (change -45%, P < .001, d = 0.98) and FADIR (change -37%, P = .003, d = 1.0), where the cam deformity accounted for 21% of the intact hip's torsional resistance in flexion 90° and 27% in FADIR.

CONCLUSION

Although the capsule played a predominant role in joint constraint, the cam deformity provided 21% to 27% of the intact hip's resistance to torsional load in flexion and internal rotation. Resecting the cam deformity would remove this loading on the chondrolabral junction.

CLINICAL RELEVANCE

These findings are the first to quantify the contribution of the cam deformity to resisting hip joint torsional loads and thus quantify the reduced loading on the chondrolabral complex that can be achieved after cam resection.