The clinical presentation, diagnosis and pathogenesis of symptomatic sports-related femoroacetabular impingement (SRFAI) in a consecutive series of 1021 athletic hips

Early Impact of Hip Arthroscopy on the Resolution of Symptom Burden in Athletes With Femoroacetabular Impingement

Background

Coexisting symptoms can confound outcomes after arthroscopic correction of femoroacetabular impingement (FAI). Symptom burden (SB) represents the cumulative load of patient-reported symptoms.

Purpose

To quantify the prevalence of symptoms in athletes before and after arthroscopic correction of FAI and evaluate the impact of independent and cumulative SB resolution on outcomes.

Study Design

Case series; Level of evidence, 4.

Methods

Included were 509 hips of 386 athletes (89% men; age, 26.4 ± 6.1 years) who underwent primary hip arthroscopy for FAI between 2011 and 2020. Symptom prevalence was assessed preoperatively and 1 year postoperatively using a 15-item SB survey, with the total number of symptoms reported as the SB score. Minimal clinically important difference (MCID-SB) and substantial clinical benefit (SCB-SB) thresholds according to the proportional pre- to postoperative resolution of SB were calculated, and 1- and 2-year postoperative patient-reported outcome measures (PROMs)-including the modified Harris Hip Score and 36-Item Short Form Survey-were compared relative to MCID-SB and SCB-SB achievement. Multivariable stepwise regression was used to evaluate the ability of individual symptom resolution for MCID and SCB achievements on PROMs.

Results

The SB score was 6 ± 2.9 preoperatively, improving to 2.8 ± 2.7 at 1 year postoperatively (P < .001). A proportional reduction in symptoms by 48.5% and 70.3% defined the MCID-SB and SCB-SB, respectively; this was achieved by 63.6% and 43.8% of the hips, respectively. Postoperatively, PROMs were superior where clinically meaningful SB resolution thresholds were achieved (P < .001). A significantly higher proportion of these cases returned to their main sport (79.4% vs 63.1% achieved MCID-SB; 83.8% vs 65.2% achieved SCB-SB) (P < .001). Odds ratios for symptoms associated with achieving the MCID on PROMs included resolution of groin pain (2.6-5.5), side hip pain (3.4), pain during (3.1) and after (2.6-3.5) activity, hamstring tightness (2.6), and limping after activity (2.6). Symptom resolution associated with achieving SCB included groin pain (3.0-3.1), pain during (3.3) and after (2.7-4.2) activity, and limping after activity (3-6.8).

Conclusion

Achieving thresholds of clinically important SB resolution was associated with superior postoperative PROM scores and higher rates of return to sports for this athletic cohort. Resolution of groin pain, pain during/after activity, hamstring tightness, and limping after activity increased the odds of achieving clinically important improvement on PROMs.

Open and arthroscopic management of femoroacetabular impingement: a review of current concepts

Femoroacetabular impingement (FAI) is a common femoral and/or acetabular abnormality that can cause progressive damage to the hip and osteoarthritis. FAI can be the result of femoral head/neck overgrowth, acetabular overgrowth or both femoral and acetabular abnormalities, resulting in a loss of native hip biomechanics and pain upon hip flexion and rotation. Radiographic evidence can include loss of sphericity of the femoral neck (cam impingement) and/or acetabular retroversion with focal or global overcoverage (pincer impingement). Operative intervention is indicated in symptomatic patients after failed conservative management with radiographic evidence of impingement and minimal arthritic changes of the hip, with the goal of restoring normal hip biomechanics and reducing pain. This is done by correcting the femoral head-neck relationship to the acetabulum through femoral and/or acetabular osteoplasty and treatment of concomitant hip pathology. In pincer impingement cases with small lunate surfaces, reverse periacetabular osteotomy is indicated as acetabular osteoplasty can decrease an already small articular surface. While surgical dislocation is regarded as the traditional gold standard, hip arthroscopy has become widely utilized in recent years. Studies comparing both open surgery and arthroscopy have shown comparable long-term pain reduction and improvements in clinical measures of hip function, as well as similar conversion rates to total hip arthroplasty. However, arthroscopy has trended toward earlier improvement, quicker recovery and faster return to sports. The purpose of this study was to review the recent literature on open and arthroscopic management of FAI.

Slipped Capital Femoral Epiphysis Associated With Athletic Activity

BACKGROUND

Little data exist regarding the association of slipped capital femoral epiphysis (SCFE) and sporting activities.

HYPOTHESIS

There is no association between SCFE and sporting activities.

STUDY DESIGN

Retrospective review of all SCFE cases at our institution from 2010 through March 2021.

LEVEL OF EVIDENCE

Level 3.

METHODS

All patients with idiopathic SCFE were reviewed looking for the presence/absence of sporting activities and symptom onset. Also collected were the age, symptom duration, and weight/height of the patient, sex, race, and stable/unstable nature of the SCFE. The severity of the SCFE was measured using the lateral epiphyseal-shaft angle.

RESULTS

There were 193 children (110 boys, 83 girls) with idiopathic SCFEs. The SCFE was stable in 147, unstable in 45, and unknown in 1. The average age was 12.1 ± 1.8 years, average SCFE angle 38° ± 20° and symptom duration 4.0 ± 5.1 months. An association with a sporting activity was present in 64 (33%). The sporting activity was basketball (18), football (11), baseball/softball (10), and others (23). Football, basketball, and soccer predominated in boys, baseball and running sports were equal between boys and girls, and cheerleading/gymnastics/dancing predominated in girls. Differences showed that those involved in sports had a slightly lower body mass index (BMI) (88th percentile vs 95th percentile, P = 0.00). There were no differences between those involved and those not those involved in sporting activities for symptom duration, SCFE severity, sex, race, or stable/unstable SCFE type.

CONCLUSION

Sporting activities are associated with the onset of symptoms in 1 of 3 of patients with SCFE, refuting the null hypothesis.

CLINICAL RELEVANCE

A high level of suspicion for SCFE should be given when any peripubertal athlete presents with hip or knee pain regardless of BMI/obesity status, and appropriate imaging performed.

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).

Hip Range of Motion Is Increased After Hip Arthroscopy for Femoroacetabular Impingement: A Systematic Review

Purpose

To investigate the impact of arthroscopic correction of symptomatic femoroacetabular impingement on postoperative hip range of motion (ROM), as an objectively measured postoperative clinically reported outcome.

Methods

A systematic review of the current literature was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, OVID/MEDLINE, EMBASE, and Cochrane databases were queried in November 2020. Studies not reporting pre- to postoperative ROM measurements were excluded. Methodologic quality was assessed using the MINORS assessment, and certainty of evidence was assessed using the GRADE approach. Effect size using standardized mean differences assessed magnitude of change between pre- and postoperative ROM.

Results

In total, 23 studies were included evaluating 2,332 patients. Mean age ranged from 18 to 44.2 years. Flexion, internal rotation (IR), and external rotation (ER) were the predominantly measured ROMs reported in 91%, 100% and 65% of studies, respectively. Observed change following hip arthroscopy was considered significant in 57.1% (flexion), 74% (IR), and 20% (ER). Effect size of change in significantly improved ROMs were weak (16.7% flexion, 33.3% ER), moderate (58.3% flexion, 29.4% IR), and large (25% flexion, 64.7% IR, 66.7% ER). For goniometric assessment mean observed changes ranged as follows: flexion: 0.1° to 12.2°; IR: 3.6° to 21.9°; ER: –2.6° to 12.8°. For computed tomography–simulated assessment, the mean observed change ranged as follows: flexion: 3.0° to 8.0°; IR 9.3° to 14.0°.

Conclusions

Outcome studies demonstrate overall increased range of flexion and IR post-hip arthroscopy, with a moderate and large effect respectively. Change in ER is less impacted following hip arthroscopy. Certainty of evidence to support this observation is low. Current research evaluating changes in this functional ability is limited by a lack of prospective studies and non-standardized measurement evaluation techniques.

Level of Evidence

Level IV, systematic review of Level II-IV studies.

Survivorship Rate and Clinical Outcomes 10 Years After Arthroscopic Correction of Symptomatic Femoroacetabular Impingement

BACKGROUND

Femoroacetabular impingement (FAI) is a common mechanical hip condition, prevalent in both the athletic and the general population. Surgical intervention is an effective treatment option that improves both symptoms and function in short- to medium-term follow-up. Few studies within the literature have reported the longer-term success of arthroscopic surgery.

PURPOSE

The aim of this study was to quantify the 10-year survivorship and clinical outcome for patients treated arthroscopically for symptomatic FAI.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients from our hip registry (n = 119) completed patient-reported outcome measures (PROMs) including the modified Harris Hip Score (mHHS), University of California Los Angeles (UCLA) activity scale, 36-Item Short Form Health Survey (SF-36), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at a minimum of 10 years after arthroscopy (range, 10-12 years). Results were compared with baseline scores using the Wilcoxon signed rank test. The associations among several prognostic factors, which included age, sex, Tönnis grade, and labral treatment, and subsequent conversion to total hip replacement (THR) or repeat hip arthroscopy (RHA) were analyzed using the chi-square analysis. Relationships between range of motion and radiological findings with clinical outcome were also examined using Pearson correlation analysis. Minimal clinically important difference (MCID) was calculated using a distribution method (0.5 standard deviation of the change score), and substantial clinical benefit (SCB) was determined using an anchor method. Finally, receiver operating characteristic curves with subsequent Youden index were used to determine cutoffs for PROMs, which equated to a Patient Acceptable Symptom State (PASS).

RESULTS

A total of 8.4% of cases required conversion to THR, and 5.9% required RHA. Statistically significant improvements in mHHS, SF-36, and WOMAC scores, with high satisfaction (90%), were observed 10 years after surgery. No significant change was seen in activity level (UCLA score) despite patients being 10 years older. A high percentage of patients achieved MCID for mHHS (88%), SF-36 (84%), and WOMAC (60%). The majority of patients also achieved PASS (62% for mHHS, 85% for UCLA, 78% for SF-36, and 84% for WOMAC) and SCB (74% for mHHS, 58% for UCLA, 52% for SF-36, and 56% for WOMAC).

CONCLUSION

Arthroscopic intervention is a safe and viable treatment option for patients with symptomatic FAI, and patients can expect long-term improvements and high satisfaction. Results indicated a high satisfaction (90%) and survivorship rate (91.6%), with excellent clinical outcome, 10 years after the initial procedure.

How does the cam morphology develop in athletes? A systematic review and meta-analysis

OBJECTIVE

A higher prevalence of cam morphology has been reported in the athletic population but the development of the cam morphology is not fully understood. The purpose of this systematic review is to establish the timing of development of the cam morphology in athletes, the proximal femoral morphologies associated with its development, and other associated factors.

DESIGN

Embase, MEDLINE and the Cochrane Library were searched for articles related to development of the cam morphology, and PRISMA guidelines were followed. Data was pooled using random effects meta-analysis. Study quality was assessed using the Downs and Black criteria and evidence quality using the GRADE framework.

RESULTS

This search identified 16 articles involving 2,028 participants. In males, alpha angle was higher in athletes with closed physes than open physes (SMD 0.71; 95% CI 0.23, 1.19). Prevalence of cam morphology was associated with age during adolescence when measured per hip (β 0.055; 95% CI 0.020, 0.091) and per individual (β 0.049; 95% CI 0.034, 0.064). Lateral extension of the epiphysis was associated with an increased alpha angle (r 0.68; 95% CI 0.63, 0.73). A dose-response relationship was frequently reported between sporting frequency and cam morphology. There was a paucity of data regarding the development of cam morphology in females.

CONCLUSIONS

Very low and low quality evidence suggests that in the majority of adolescent male athletes, osseous cam morphology developed during skeletal immaturity, and that prevalence increases with age. Very low quality evidence suggests that osseous cam morphology development was related to lateral extension of the proximal femoral epiphysis.

Sex differences in the prevalence of radiographic findings of structural hip deformities in patients with symptomatic femoroacetabular impingement

The purpose of this study was to determine the sex differences in the overall prevalence of radiographic femoroacetabular impingement (FAI) deformity patients presenting with hip pain and to identify the most common radiographic findings in male and female patients. A geographic database was used to identify patients between the age of 14 and 50 years with hip pain from 2000 to 2016. A chart and radiographic review was performed to identify patients with cam, pincer and mixed-type FAI. A total of 374 (449 hips) out of 612 (695 hips) male patients and 771 (922 hips) out of 1281 (1447 hips) female patients had radiographic features consistent with FAI. Ninety-four male hips (20.9%) and 45 female hips (4.9%) had cam type, 20 male hips (4.5%) and 225 female hips (24.4%) had pincer type and 335 male hips (74.6%) and 652 female hips (70.7%) had mixed type. The overall prevalence of radiographic findings consistent with FAI in male and female patients with hip pain was 61.1% and 60.2%, respectively. Mixed type was the most prevalent. The most common radiographic finding for cam-type FAI was an alpha angle >55°, and the most common radiographic finding for pincer-type FAI was a crossover sign. Male patients were found to have a higher prevalence of cam-type deformities, whereas female patients were found to have a higher prevalence of pincer-type deformities.

Arthroscopic Correction of Femoroacetabular Impingement for Concomitant Inguinal Disruption in Athletes With Dual Pathology

BACKGROUND

Inguinal disruption and femoroacetabular impingement (FAI) are well-recognized sources of groin pain in athletes; however, the relationship between inguinal disruption and FAI remains unclear. In cases of dual pathology, where both entities coexist, there is no definitive consensus regarding which pathology should be prioritized for treatment in the first instance.

PURPOSE

(1) To examine the 2-year effectiveness and clinical outcome in athletes presenting with dual pathology in which the FAI component alone was treated with arthroscopic deformity correction. (2) To compare 2-year patient-reported outcome measures between athletes undergoing only hip arthroscopy (HA) and athletes undergoing groin repair and HA.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

All patients undergoing HA for the treatment of FAI with concomitant clinical signs of inguinal disruption at initial consultation were between 2010 and 2016 were included in this study. Inclusion criteria were male sex, age <40 years, and involvement in competitive sporting activity. Athletes with previous HA on the symptomatic side, Tönnis grade >1, or lateral center-edge angle <25° were excluded. Revision HA or subsequent groin surgery was documented. Outcome evaluation consisted of validated patient-reported outcome measures (modified Harris Hip Score; University of California, Los Angeles Activity Scale; 36-Item Short Form Health Survey; Western Ontario and McMaster Universities Osteoarthritis Index) completed preoperatively and a minimum 2 years postoperatively. The minimal clinically important difference was assessed by using a distribution-based technique (SD, 0.5) and an anchor-based technique (percentage of possible improvement). Level of satisfaction and return to play were assessed.

RESULTS

A total of 113 cases of dual pathology were included in 91 patients with a mean ± SD age of 26.3 ± 5.1 years. The index surgical procedure was HA for 104 cases (92%) and groin repair for 9 (8%). For patients undergoing HA as the index procedure, 98.1% (102/104 cases) were successfully followed up to establish survivorship. In 89.2% (91/102 cases), no additional groin surgery was required. In 11 cases (10.8%), additional groin surgery was required for persisting inguinal-related groin pain. At 2 years after the operation, there was no difference for any patient-reported outcome measure (P > .099), improvement from baseline (P > .070), or proportion of cases achieving the minimal clinically important difference (P > .120) between the HA-only group and the group undergoing HA and groin repair at any stage. There was also no difference between groups in terms of return-to-play rate (P = .509) or levels of satisfaction (pain, P = .204; performance, P = .345).

CONCLUSION

In patients with dual pathology, treatment of the FAI component alone using arthroscopic hip surgery results in a successful outcome without need for groin repair in 89.2% of cases. No statistical difference in clinical outcome 2 years after surgery was observed between athletes undergoing 1 procedure (HA alone) and those undergoing 2 procedures (HA and groin repair at any stage).

Comparing Patient-Reported Outcome Measurements for Femoroacetabular Impingement Syndrome

BACKGROUND

There is much debate in the current literature with regard to the most appropriate hip-specific patient-reported outcome (PRO) measurement for assessment of femoroacetabular impingement syndrome (FAIS) and outcomes after surgical treatment. Despite systematic reviews assessing the validity of classic hip-specific PROs as well as newer PROs developed to target the young, active population, there lacks a direct comparison of the question content between each PRO.

PURPOSE

To compare the question composition and degree of overlap between commonly used PROs for FAIS.

STUDY DESIGN

Cross-sectional study.

METHODS

A literature review yielded the 6 most commonly cited PROs for assessment of FAIS: modified Harris Hip Score (mHHS), Hip disability and Osteoarthritis Outcome Score (HOOS), Copenhagen Hip and Groin Outcome Score (HAGOS), Nonarthritic Hip Score (NAHS), international Hip Outcome Tool (iHOT-33), and Hip Outcome Score (HOS). Questions from each PRO were classified as identical, similar, or unique after pooled comparison, and the number of overlapping (identical or similar) questions between each PRO was determined. Questions were then classified into 5 domains: pain, symptoms, functional activities, sports, and quality of life, and variations in questions assessing each domain based on PRO were analyzed.

RESULTS

Analysis of 164 total questions from 6 PROs showed that 87 questions (53%) were identical between 2 or more PROs, 39 (24%) were similar, and 38 (23%) were unique. The iHOT-33 contained the highest number of unique questions, with 13 of 33 (39.4%), while the HOOS contained the lowest number of unique questions, with 3 of 40 (7.5%). The HOOS, HAGOS, and iHOT-33 contained questions assessing all 5 domains of patient outcomes; the NAHS did not evaluate quality of life; the mHHS only assessed pain, symptoms, and functional activities; and the HOS only assessed functional activities and sports.

CONCLUSION

As there is a high percentage of overlapping (identical or similar) questions between the most commonly used hip-specific PROs for FAIS, multiple tests may be appropriate for use. The iHOT-33, HOOS, and HAGOS are well suited for the general population as they offer comprehensive assessments across all domains, while the HOS provides added focus to sports/activity assessments for athletes and highly active patients.

Arthroscopic Correction of Sports-Related Femoroacetabular Impingement in Competitive Athletes: 2-Year Clinical Outcome and Predictors for Achieving Minimal Clinically Important Difference

Background:

A growing body of literature supports surgical intervention for femoroacetabular impingement (FAI) in young, active athletes. However, factors likely to influence results in this cohort are less clearly defined.

Purpose:

To quantify changes in validated patient-reported outcome measures (PROMs) and determine whether differences in baseline athlete demographic characteristics, intraoperative findings, and surgical techniques are associated with achieving improved outcomes and minimal clinically important difference (MCID) after arthroscopic management of sports-related FAI.

Study Design:

Case series; Level of evidence, 4.

Methods:

Data were prospectively collected from competitive athletes who underwent hip arthroscopy between January 2009 and February 2017. Athletes who underwent primary arthroscopic correction of sports-related FAI with labral repair were included providing they had a Tönnis grade ≤1 and a lateral center-edge angle ≥20°, excluding significant articular cartilage injury and lateral rim dysplasia. The modified Harris Hip Score, Western Ontario and McMaster Universities Osteoarthritis Index, University of California Los Angeles activity scale, and 36-Item Short Form Health Survey were used to measure outcomes at the 2-year follow-up. MCID was measured using 3 methods: a mean change method, a distribution-based method, and the percentage of possible improvement (POPI) method. Multivariate regression models were used to assess a number of diagnostic and surgical variables associated with good outcome and achieving MCID at follow-up.

Results:

At 2-year follow-up, statistically significant improvements were observed for all PROMs (P < .001 for all), and 84% of athletes continued to play sport. Higher preoperative PROM scores reduced the likelihood of achieving MCID; however, returning to play was the strongest predictor of reaching MCID in this athletic cohort. Using absolute score change (mean change or distribution method) to calculate MCID was less accurate owing to ceiling effects and dependence on preoperative PROM scores.

Conclusion:

Athletes undergoing arthroscopy for sports-related FAI can expect a successful outcome and continued sports participation at 2 years postoperatively. The majority of athletes will achieve MCID. The POPI method of MCID calculation was more applicable to higher functioning athletic cohorts. Reduced preoperative PROM scores and the ability to return to sport increased the likelihood of achieving MCID in this population.

Chronic Hip Injury Has a Negative Emotional Impact on the Male Athlete With Femoroacetabular Impingement

PURPOSE

To evaluate the impact of hip arthroscopy for femoroacetabular impingement (FAI) on both the physical and mental components of the 36-Item Short Form (SF-36) and assess how changes in health status compare with improvements in physical function and ability to continue to play (CTP) 2 years after surgery.

METHOD

Data collected prospectively from male athletes undergoing primary arthroscopic correction of FAI between November 2008 and October 2016 were analyzed. Physical (PCS) and mental (MCS) component scores of the SF-36 were assessed preoperatively and 2 years postoperatively. The minimal clinical important difference (MCID) was calculated using an anchor-based percentage of possible improvement technique, and the proportion of athletes achieving MCID was established. Logistic regression analysis was used to identify predictors of achieving MCID. CTP was assessed at 2-year follow-up.

RESULTS

486 cases were included, age 25.9 ± 5.6 years. Median PCS improved from baseline 69.4 (51.9 to 85.0) to 91.9 (81.9 to 97.5) at 2 years (P < .001). Median MCS remained unchanged-preoperative, 88 (76 to 92); postoperative, 88 (80 to 96)-although the difference in the distribution of scores was statistically significant (P < .001). Calculated MCID was 60.1% (PCS) and 58.1% (MCS). Mean improvement was significantly higher for PCS compared with MCS (17.4 versus 3.7, P < .001) The proportion of cases achieving MCID was 56.9% and 28.7% for PCS and MCS, respectively, and the difference was statistically significant (P < .001). Lower Tonnis grade (odds ratio [OR] 0.601, 95% confidence interval [CI] 0.377 to 0.958; P = .032) and symptom duration <2 years (OR 0.624, 95% CI 0.406 to 0.960; P = .032) were predictive of achieving PCS MCID. Higher preoperative scores decreased the odds of achieving MCID (OR 0.965, 95% CI 0.955 to 0.975; P < .001; OR 0.972, 95% CI 0.958 to 0.986; P < .001 for PCS and MCS, respectively). 77.3% continued to play their main preinjury sport. Where CTP was not achieved, a significantly higher proportion of cases failed to meet MCID for the MCS compared with PCS (85% versus 60%, P < .001).

CONCLUSION

Arthroscopic management of sports-related FAI results in excellent overall clinical outcome and high levels of satisfaction and CTP at 2 years. Chronic hip injury has a significant negative effect on the physical and mental well-being of athletes; corrective surgery may restore physical function but is more limited in its ability to improve mental health status in this athletic cohort.

LEVEL OF EVIDENCE

IV, therapeutic case series.

Less hip range of motion is associated with a greater alpha angle in people with longstanding hip and groin pain

PURPOSE

A higher alpha angle has been proposed to correlate with lower hip range of motion, but the association in people with longstanding hip and groin pain is currently unclear. The aims were to: (1) assess the association between range of motion and alpha angle in patients with longstanding hip and groin pain; (2) examine if a cut-off value in range of motion variables could identify patients with an alpha angle above or below 60°.

METHODS

Seventy-two participants were consecutively recruited from an orthopaedic department after referral for hip- and groin-related pain. Passive hip range of motion was measured in flexion, internal rotation with 90° hip flexion, internal rotation in neutral hip position, external rotation with 90° hip flexion, and abduction. The alpha angle was calculated from a frog-leg lateral radiograph. Linear regression examined the association between range of motion and alpha angle, and an ROC-curve analysis was performed to identify the sensitivity and specificity of range of motion cut-offs.

RESULTS

Lower range of motion in internal rotation in flexion, external rotation, and abduction were associated with higher alpha angle. Internal rotation of 27° or less displayed good sensitivity (81%) and specificity (85%) to detect an alpha angle above 60°, while a cut-off of 41° in external rotation and 27° in abduction showed a sensitivity of 72% and specificity of 50% and 60%, respectively.

CONCLUSION

Less internal rotation in flexion, external rotation, and abduction are associated with a greater alpha angle in a cohort of people with longstanding hip and groin pain. A cut-off of 27° in internal rotation has good sensitivity and specificity to identify people with an alpha angle above or below 60° and have the potential to be used in the clinical setting to identify patients that require further imaging, or that are unlikely to have cam morphology.

LEVEL OF EVIDENCE

II.

Recreational Sports and Intra-articular Hip Injuries in Patients Undergoing Hip Arthroscopy for Femoroacetabular Impingement

Purpose

We aimed to determine the relationship between recreational sports and intra-articular hip injuries in an active population that had undergone hip arthroscopy for femoroacetabular impingement syndrome.

Methods

A retrospective review was performed of prospectively collected data from patients undergoing hip arthroscopy between January 2015 and December 2016. Inclusion criteria included patients between 18 and 50 years of age who had participated in recreational sports prior to surgery and had a minimum of a 2-year follow-up. Labral injury was evaluated using the Multicenter Arthroscopic Hip Outcome Research Network classification, and rim chondral injuries were evaluated using the Acetabular Labral Articular Disruptions system. Ligamentum teres tear and psoas impingement were also recorded. Sports were classified as rotational running (soccer, basketball, handball), flexibility (martial arts, dance), asymmetric-overhead (racquet), or endurance (running, swimming, cycling). Primary univariate analysis of sports’ independent associations, demographic characteristics, intra-articular hip injuries, and outcomes was performed.

Results

Patients included 185 people with a mean age of 36.7 years. Patients participating in rotational running sports and flexibility sports had a significantly greater proportion of rim chondral injuries than those participating in endurance sports or asymmetric overhead sports (P = 0.02). Ligamentum teres tears were significantly associated with flexibility sports (P < 0.001). A total of 84.7%, 67.7%, 67.2%, and 71.2% of patients met minimal clinically important difference levels for the modified Harris Hip Score (mHHS), the Hip Outcome Score (HOS)¹⁰ questionnaire with activities of daily living (HOS-ADL), the sports subscale (HOS-SSS), and the International Hip Outcome Tool (iHOT-12), respectively; 94.9%, 66.2% and 62.7% met the patient acceptable symptom state for mHHS, HOS-ADL, and HOS-SSS, respectively; 86.7%, 48.5%, 47.8%, and 32.4% found substantial clinical benefit for mHHS, HOS-ADL, HOS-SSS, and iHOT-12, respectively.

Conclusions

Rotational running sports were significantly associated with rim chondral injuries. Flexibility sports were significantly associated with rim chondral injuries and ligamentum teres tears. Athletes participating in these sports are more likely to have intra-articular hip injuries than those in the other sports categories.

Level of Evidence

Level IV, prognostic case series.

Return to Sport After Hip Arthroscopy for Femoroacetabular Impingement Syndrome in NCAA Division I Athletes: Experience at a Single Institution

Background:

The rate of return to sport after surgical treatment of femoroacetabular impingement (FAI) syndrome (FAIS) has been studied in high-level athletes. However, few studies examining this rate have focused exclusively on National Collegiate Athletic Association (NCAA) Division I athletes.

Purpose:

To evaluate the return-to-sport rate after hip arthroscopy for FAIS and to examine the influence of sport type on the clinical presentation of FAIS in collegiate athletes.

Study Design:

Case series; Level of evidence, 4.

Methods:

Included in this study were NCAA Division I student-athletes who underwent hip arthroscopy for FAIS at our institution between 2010 and 2017. Exclusion criteria were history of previous hip pathology, pediatric hip disease, radiographic evidence of osteoarthritis (Tönnis grade >0), prior lower extremity procedure, history of chronic pain, osteoporosis, or history of systemic inflammatory disease. Athletes were categorized into 6 subgroups based on the type of sport (cutting, contact, endurance, impingement, asymmetric/overhead, and flexibility) by using a previously reported classification system. Patient characteristics and preoperative, intraoperative, and return-to-sport variables were compared among sport types.

Results:

A total of 49 hip arthroscopies for FAIS were performed in 39 collegiate athletes (10 females, 29 males; mean age, 19.5 ± 1.3 years). A total of 1 (2.6%) cutting athlete, 15 (38.5%) contact athletes, 8 (20.5%) impingement athletes, 6 (15.4%) asymmetric/overhead athletes, and 9 (23.1%) endurance athletes were included in the study. There were no differences among sports groups with respect to the FAI type. Endurance athletes had lower rates of femoral osteochondroplasty (45.5%) and labral debridement (0.0%) (P < .0001). Contact sport athletes had higher rates of labral debridement (50.0%; P < .0001). Patients were evaluated for return to sport at an average of 1.96 ± 0.94 years. Overall, the return-to-sport rate was 89.7%. There were no differences in return-to-sport rates based on the sport type except for endurance athletes, who returned at a lower rate (66.6%; P < .001). No differences in return-to-sport rate (P = .411), duration after return (P = .265), or highest attempted level of sport resumed (P = .625) were found between patients who underwent labral repair versus debridement.

Conclusion:

Collegiate-level athletes who underwent hip arthroscopy for FAIS returned to sport at high and predictable rates, with endurance athletes possibly returning to sport at lower rates than all other sport types. Surgical procedures may be influenced by sport type, but the rate of return to sport between athletes who underwent labral debridement versus labral repair was similar.

Pathomechanics Underlying Femoroacetabular Impingement Syndrome: Theoretical Framework to Inform Clinical Practice

Over the last decade, there has been a marked increase in attention to, and interest in, femoroacetabular impingement syndrome (FAIS). Despite continued efforts by researchers and clinicians, the development, progression, and appropriate treatment of FAIS remains unclear. While research across various disciplines has provided informative work in various areas related to FAIS, the underlying pathomechanics, time history, and interaction between known risk factors and symptoms remain poorly understood. The purpose of this perspective is to propose a theoretical framework that describes a potential pathway for the development and progression of FAIS. This paper aims to integrate relevant knowledge and understanding from the growing literature related to FAIS to provide a perspective that can inform future research and intervention efforts.

Routine Interportal Capsular Repair Does Not Lead to Superior Clinical Outcome Following Arthroscopic Femoroacetabular Impingement Correction With Labral Repair

PURPOSE

To evaluate the impact of routine capsular repair on clinical outcome in a consecutive series of patients undergoing arthroscopic correction of symptomatic femoroacetabular impingement.

METHODS

Between 2009 and 2015, patients were assigned to 1 of 2 groups based on whether a capsular repair was performed as part of their index hip arthroscopic procedure. Exclusion criteria included previous underlying hip conditions, Tönnis >1, age >45 years, and labrum not repaired. Patients were assessed preoperatively and 2-years postoperatively using patient-reported outcome measures (PROMs), including the modified Harris hip score (mHHS), UCLA activity scale, short form-36, Western Ontario and McMaster Universities Osteoarthritis Index score, and measures of range of hip movements. The incidence of any subsequent revision surgery within 2 years was recorded. Sex and age groups were specifically analyzed.

RESULTS

In total, 966 consecutive cases were included (96.4% follow-up rate): 508 in group A (no repair) and 458 in group B (repair). Average age for all cases was 28.1 ± 7.0 years (14.6-44.9). There were significant improvements in all PROMs following surgery for both groups (P < .001). Statistical significance between groups at 2 years was observed for Short Form-36 (P = .001) and WOMAC (P = .041), greater in group A. Both groups similarly met the minimal clinically important difference (mHHS P = .414 and .605; UCLA, P = .549 and .614; Short Form-36, P = .455 and .079; WOMAC, P = .425 and .750 for distribution and anchor-based methods, respectively). In total, 38 (7.8%) cases group A and 24 (5.4%) cases group B required repeat hip arthroscopy (HA) (P = .148); No (0%) cases in group A and 2 (0.45%) cases in group B required total hip replacement (P = .226). There was significantly lower rate of repeat HA among 25- to 34-year age group (8.6% vs 3.9%, P = .047) where capsular repair was performed. No significant difference in the rate of repeat HA between groups for male (P = .203) or female (P = .603) subjects. Adhesions were more common in the repair group (79.2%, 95% confidence interval [CI] 57.8-92.9 vs 55.3%, CI 38.3-71.4; P = .055), with further capsular repair/plication required more frequently in the unrepaired group (50%, CI 33.4-66.6 vs 25%, CI 10.8-44.3); however, differences between groups were not significant (P = .051). Internal rotation was larger in group A compared with group B at 2 years (36.2 vs 28.1, P = .000). Female patients with capsular repair had reduced PROM scores at 2 years compared with female patients without repair (WOMAC, P = .004, and mHHS, P = .037).

CONCLUSIONS

Arthroscopic correction of femoroacetabular impingement with labral repair results in significant improvements in patient-reported outcomes at 2-years postsurgery, irrespective of whether the capsule is repaired. Routine capsular repair in a consecutive series of patients did not lead to superior outcomes compared with a nonrepaired group; similar proportions of cases in both groups were able to achieve minimal clinically important difference. In female patients, routinely repairing the capsule may lead to statistically inferior clinical outcome at 2-years postsurgery, although this may not be clinically significant. Routine capsular repair, however, may be beneficial in the younger, active patient, where a significant reduction in repeat arthroscopy was observed.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Defining the Minimal Clinically Important Difference in Athletes Undergoing Arthroscopic Correction of Sports-Related Femoroacetabular Impingement: The Percentage of Possible Improvement

BACKGROUND

Measures of clinically meaningful improvement in patient-reported outcomes within orthopaedics are becoming a minimum requirement to establish the success of an intervention.

PURPOSE

To (1) define the minimal clinically important difference (MCID) at 2 years postoperatively in competitive athletes undergoing hip arthroscopic surgery for symptomatic, sports-related femoroacetabular impingement utilizing existing anchor- and distribution-based methods and (2) derive a measure of the MCID using the percentage of possible improvement (POPI) method and compare against existing techniques.

STUDY DESIGN

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

METHODS

There were 2 objective outcome measures-the modified Harris Hip Score (mHHS) and 36-Item Short Form Health Survey (SF-36)-administered at baseline and 2 years postoperatively. External anchor questions were used to determine the MCID through mean change, mean difference, and receiver operating characteristic (ROC) techniques. Distribution-based calculations consisted of 0.5 SD, effect size, and standard error of measurement techniques. The POPI was calculated alongside each technique as an achieved percentage change of maximum available improvement for each athlete relative to the individual baseline score. The impact of the preoperative baseline score on the MCID was assessed by assigning athletes to groups determined by baseline percentiles. Statistical analysis was performed, with P < .05 considered significant.

RESULTS

There were 576 athletes (96% male; mean age, 25.9 ± 5.7 years). The MCID score change (and POPI) for the mHHS and SF-36 ranged from 2.4 to 16.7 (21.6%-63.6%) and from 3.3 to 24.9 (22.1%-57.4%), respectively. The preoperative threshold value for achieving the ROC-determined MCID was 80.5 and 86.5 for the mHHS and 70.1 and 72.4 for the SF-36 for the patient-reported outcome measure (PROM) score- and POPI-calculated MCID, respectively. Through the commonly used mean change method, 40.0% (mHHS) and 42.4% (SF-36) of athletes were unable to achieve the MCID because of high baseline scores and PROM ceiling effects compared with 0% when the POPI technique was used. A highly significant difference for the overall MCID was observed between preoperative baseline percentile groups for the mHHS (P = .014) and SF-36 (P = .004) (improvement in points), while there was no significant difference between groups for either the mHHS (P = .487) or SF-36 (P = .417) using the POPI technique.

CONCLUSION

The MCID defined by an absolute value of improvement was unable to account for postoperative progress in a large proportion of higher functioning athletes. The POPI technique negated associated ceiling effects, was unrestricted by the baseline score, and may be more appropriate in quantifying clinically important improvement.