Physical impairments and activity limitations in people with femoroacetabular impingement: a systematic review

Efficacy and safety of arthroscopy in femoroacetabular impingement syndrome: a systematic review and meta-analysis of randomized clinical trials

This study aimed to compare the efficacy and safety of arthroscopy with physiotherapy or joint lavage in patients with femoroacetabular impingement (FAI). A meta-analysis using PubMed, Embase, Scopus, and the Cochrane Collaboration Library databases was performed in September 2022. We included studies focusing on patients with FAI who underwent arthroscopic surgery versus those who underwent physiotherapy or arthroscopic lavage. The outcomes were functional scores (iHOT-33 and HOS ADL) and adverse events. Randomized clinical trials were included in the study. The risk of bias in each study was assessed according to Cochrane guidelines for clinical trials. The data were combined using Review Manager version 5.4. (PROSPERO CRD42022375273). Six RCTs were included, from a pool of 839 patients (407 females). There were no significant differences between groups at 6 months regarding iHOT-33 (MD 4.68, 95% CI -0.07 to 9.44) and HOS ADL (MD 5.09, 95% CI -0.07 to 10.24). The iHOT-33 and HOS ADL scales showed significant differences at 12 months in favor of the arthroscopy group (MD 10.65, 95% CI 6.54 to 14.76) and (MD 8.06, 95% CI 1.05 to 15.07). MCID was not achieved through arthroscopy in functional variables. The rate of numbness was significantly higher in the arthroscopy group. Although the arthroscopy group demonstrated statistical superiority, the clinical significance based on the MCID remains controversial, and arthroscopy did not demonstrate clinical superiority.

More is not always better-association between hip range of motion and symptom severity in patients with femoroacetabular impingement syndrome: A cross-sectional study

BACKGROUND

Restricted hip range of motion (ROM) is a common finding in patients with femoroacetabular impingement (FAI) syndrome. However, the association between hip ROM and symptom severity in these individuals is unclear.

OBJECTIVE

Explore associations between symptom severity and hip flexion and rotation ROM in patients with FAI syndrome and determine if ROM measures can discriminate those with worse symptoms.

METHODS

Data from 150 participants with FAI syndrome were analysed. A digital inclinometer was used to measure hip flexion, internal rotation, and external rotation ROM. Symptom severity was quantified using the symptoms subscale of the international Hip Outcome Tool questionnaire (iHOT-Symptoms). Multivariable fractional polynomial analyses explored associations between hip ROM measures and symptom severity. Receiver operator characteristic curves explored the ability of ROM measurements to discriminate participants with different symptomatic states.

RESULTS

Smaller hip flexion ROM values were associated with worse iHOT-Symptoms scores (p < 0.01; R2=0.242); with the polynomial concave association attenuated at approximately 120° of hip flexion ROM. Hip internal rotation was weakly associated with iHOT-Symptoms score (p = 0.01; R2=0.033). Hip external rotation ROM was not associated with iHOT-Symptoms score (p = 0.06). A hip flexion value of 107° best discriminated mild to moderate and severe symptom states (sensitivity 92%, specificity 52%).

CONCLUSION

Less hip flexion ROM was associated with worse symptoms in patients with FAI syndrome. Patients with hip flexion ROM ≥ 107° had a 15-fold decrease in the likelihood of having severe symptoms. Hip rotation ROM measures do not have a clinically meaningful association with symptom severity.

Running biomechanics in people with femoroacetabular impingement syndrome: A cross-sectional analysis of sex differences and relationships with patient reported outcome measures

OBJECTIVES

(i) Investigate if lower-limb running biomechanics differ between women and men with femoroacetabular impingement syndrome, and (ii) explore whether sex-specific relationships between lower-limb running biomechanics and symptom severity and sport-related concerns exist.

DESIGN

Cross-sectional.

SETTING

Gait laboratory.

PARTICIPANTS

Twenty women and 22 men enrolled in a clinical trial of physiotherapist-led treatments for femoroacetabular impingement syndrome.

MAIN OUTCOME MEASURES

Kinematics and kinetics of hip, knee, and ankle joints during the stance phase (calculated from three-dimensional biomechanics data) were compared using statistical parametric mapping. The International Hip Outcome Tool-33 and Copenhagen Hip and Groin Outcomes Score quantified hip-related symptom severity and sport-related concerns.

RESULTS

Women had larger hip adduction angles (34%-44% of stance,p = 0.045) than men. For kinetics, women displayed larger external hip extension moments (77%-100%,p = 0.001), smaller knee extension moments (80%-100%,p = 0.007), and smaller ankle dorsiflexion moments (26%-67%,p < 0.001) than men. Worse sport-related concern was associated with a larger peak hip extension angle (0.18, 95%CI 0.05,0.31) and smaller hip flexion moment impulse (0.14∗10-2, 95% CI 0.02∗10-2,0.25∗10-2) in women, and smaller hip external rotation moment impulse in men (0.06∗10-2, 95% CI 0.01∗10-2,0.11∗10-2).

CONCLUSIONS

Women and men with FAI syndrome display differences in lower-limb running biomechanics and relationships between symptom severity and running biomechanics are sex-dependent, warranting consideration in future analyses.

Hip Active Range of Motion in Patients with Femoroacetabular Impingement Syndrome

Femoroacetabular impingement syndrome (FAIS) is characterized by hip pain and restricted range of motion (ROM), typically due to structural conflict between the femoral neck and the acetabulum. This study aimed to quantify active ROM limitations in FAIS patients, comparing them with healthy controls to establish normative values, particularly in non-conflicting directions. Methods: A total of 53 FAIS patients scheduled for hip arthroscopy were compared to 49 healthy matched controls. Active ROM was assessed using inertial measurement unit (IMU) sensors, with measurements taken in standing and prone positions. Outcomes included flexion, external rotation, internal rotation, and total rotation ROM, alongside demographic and radiographic data. Gender-based ROM differences were also analyzed. Results: FAIS patients demonstrated significant reductions in flexion, internal rotation, and total rotation ROM in the involved hip, with large effect sizes, while external rotation remained unaffected. ROM in the uninvolved hip was also lower than in controls but showed increased external rotation. Gender differences were observed, with females exhibiting significantly higher internal rotation and, in healthy controls, greater total rotation than males. Conclusions: FAIS patients have significant active ROM restrictions in non-conflicting directions, suggesting broader joint limitations potentially tied to early hip osteoarthritis or capsular and musculoskeletal adaptations. Gender differences highlight the importance of individualized ROM assessment. This study introduces IMU-based ROM evaluation as a promising tool for diagnosing and monitoring FAIS, providing insights into functional impairments that can be used to guide targeted interventions.

The association between hip adductor and extensor strength, and hip-related patient-reported outcomes in patients with longstanding hip and groin pain: An exploratory cross-sectional study

OBJECTIVE

The objective of this study was to assess the association between hip muscle strength and hip-related patient-reported outcome measures (PROMs) in patients with longstanding hip and groin pain (LHGP).

DESIGN

Cross-sectional design.

SETTING

Orthopedic care.

PARTICIPANTS

Eighty-one patients with LHGP were consecutively recruited.

MAIN OUTCOME MEASURES

Hip muscle strength was measured in adduction and extension. Hip-related PROMs was measured with the Copenhagen Hip and Groin Outcome Score (HAGOS) which includes six subscales (Symptoms, Pain, Activity in Daily Living (ADL), Physical Function in Sports and Recreation (Sport/Rec), Participation in Physical Activities (PA), and Quality of Life (QoL). Linear regression examined the association between hip muscle strength and each HAGOS subscale.

RESULTS

Greater isometric hip muscle strength in adduction was associated with better HAGOS score for Pain and ADL (p ≤ 0.037), but not for Symptoms, Sport/Rec, PA, or QoL (p ≥ 0.154). Greater isometric hip muscle strength in extension was associated with better HAGOS score for Symptoms, Pain, and ADL (p ≤ 0.034), but not for Sport/Rec, PA, or QoL (p ≥ 0.084).

CONCLUSIONS

In patients with LHGP, greater isometric hip muscle strength seems to be associated with less symptoms and pain, and better function in ADL. No association was found for Sport/Rec, PA, or QoL.

Relationship Between Hip and Groin Pain and Hip Range of Motion in Amateur Soccer and Australian Rules Football Players

Background

The relationship between hip/groin pain and hip range of motion (ROM) is unclear.

Purpose

To explore the relationship between hip/groin pain and hip joint ROM and examine the influence of sex and cam morphology on this relationship.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Included were 184 amateur soccer and Australian Rules football players (276 hips; 20% women; median age, 26 years; interquartile range, 24-30 years) with hip/groin pain >6 months and a positive flexion-adduction-internal-rotation (FADIR) test, and 50 matched asymptomatic control players (98 hips; 28% women, median age, 26 years; interquartile range, 23-31 years). Hip ROM measures were flexion, internal and external rotation at 90° of hip flexion, total rotation (internal and external), and bent-knee fall out (BKFO). Cam morphology was determined from anteroposterior pelvis or 45° Dunn radiographs, defined by an alpha angle ≥60°. Linear regression models with generalized estimating equations were used to examine the relationship between group (symptomatic and asymptomatic) and each ROM measure. Interaction terms (group × cam morphology or group × sex) were included to examine if relationships between group and hip ROM were influenced by cam morphology or sex. Where appropriate, models were adjusted for sex, age, and cam morphology.

Results

An interaction between the relationship between group × cam and internal rotation ROM was found. Symptomatic players with cam morphology had lower internal rotation ROM than controls with cam morphology (adjusted mean difference [AMD] = -4.5°; 95% CI, -7.4° to -1.6°). Hip/groin pain was not associated with internal rotation ROM if cam morphology was absent. A significant interaction was also found for group × sex and BKFO and total rotation ROM. Symptomatic women had lower total rotation ROM than control women (AMD = -8.2°; 95% CI, -14.1° to -2.2°), but no difference was seen in men. BKFO range was lower in men with hip/groin pain compared with control men (AMD = 1.6 cm; 95% CI, 0.3-3.0 cm), but no difference was seen in women. Flexion and external rotation ROM did not differ between symptomatic and control hips.

Conclusion

Cam morphology was an effect modifier of the relationship between hip/groin pain and internal rotation ROM. Sex-related differences were also observed in the relationship between hip/groin pain and hip ROM.

Comparison of Step-Based Metrics Under Laboratory and Free-Living Conditions in Femoroacetabular Impingement Syndrome

CONTEXT

Femoroacetabular impingement syndrome (FAIS) causes pain and functional limitations. Little is known regarding walking characteristics, volume, and intensity evaluated in laboratory and free-living conditions and whether these measures differ between those with FAIS and uninjured individuals.

OBJECTIVE

To examine the differences in laboratory gait measures and free-living step-based metrics between individuals with FAIS and uninjured control participants.

DESIGN

Comparative, cross-sectional study.

PATIENTS OR OTHER PARTICIPANTS

We enrolled 25 participants with FAIS and 14 uninjured controls.

MAIN OUTCOME MEASURE(S)

We evaluated laboratory spatiotemporal gait measures (cadence, velocity, step length, stride length) during self-selected and fast walking speeds using an instrumented walkway. Participants then wore an accelerometer around the waist during waking hours for 7 consecutive days. Free-living step-based metrics included average daily steps, peak 1- and 30-minute cadence, and average daily time spent in walking cadence bands. We compared laboratory gait measures and step-based metrics between groups.

RESULTS

The groups did not differ in laboratory spatiotemporal gait measures during both speeds (all P > .05). The FAIS group took fewer daily steps (5346 ± 2141 versus 7338 ± 2787 steps/d; P = .030) and had lower peak 1-minute (92.9 ± 23.9 versus 119.6 ± 16.3 steps/min; P < .001) and 30-minute cadences (60.9 ± 27.1 versus 86.8 ± 22.4 steps/min; P = .003) compared with uninjured controls, respectively. The FAIS group also spent less time in slow (6.0 ± 3.6 versus 10.3 ± 3.4 min/d; P = .001), medium (4.5 ± 4.2 versus 8.9 ± 4.4 min/d; P = .005), and brisk/moderate (4.5 ± 6.2 versus 12.2 ± 10.3; P = .020) cadence bands compared with uninjured controls.

CONCLUSIONS

Clinical/laboratory gait measures alone may not be representative of real-world walking-related physical activity behavior in individuals with FAIS.

Will you get what you want? Treatment goals and expectations of patients with femoroacetabular impingement syndrome regarding physiotherapist-led treatment

OBJECTIVE: To (i) investigate the goals and expectations of participants enrolled in a clinical trial of physiotherapist-led treatment for femoroacetabular impingement (FAI) syndrome and (ii) explore associations between their expectations and self-reported hip burden and kinesiophobia. METHODS: Data from 150 participants with FAI syndrome who participated in a clinical trial were analysed. Participants described their most important treatment goal and the expectation of achieving this goal throughout physiotherapy treatment. The International Hip Outcome Tool (iHOT-33) subscales were used to assess self-reported hip burden. The Tampa Scale for Kinesiophobia was used to assess kinesiophobia. Participants goals were qualitatively analysed using content analysis. Linear regression was used to explore associations between patient expectations and iHOT and Tampa Scale for Kinesiophobia scores. RESULTS: Participants with FAI syndrome reported goals relating to exercise (52%), improving activities of daily living quality (23%), improving physical function (15%), and reducing pain (10%). Negative expectations regarding physiotherapist-led treatment were reported by 68% of participants. Those with negative expectations reported worse scores for the iHOT-Total score (mean difference = 12 points, 95%CI = [4 to 19]), and iHOT-Symptoms (14 points, [7 to 21]) and iHOT-Social (11 points, [2 to 21]) subscales compared to those with positive expectations. Treatment expectations were not associated with iHOT-Sport, iHOT-Job, and Tampa Scale for Kinesiophobia scores (p > 0.05). CONCLUSION: Patients with FAI syndrome had a generally negative expectation of physiotherapist-led treatment. There was a mismatch between patients' goals and current treatment approaches. Participants with FAI syndrome and negative expectations reported worse quality of life, symptoms, and social concerns than those with positive expectations.

A New Clinical Examination Algorithm to Prescribe Conservative Treatment in People with Hip-Related Pain

Hip-related pain is a common issue in active adults affecting their quality of life, mobility, and overall function, and it can lead to persistent disability. However, diagnosing hip-related pain is challenging due to the many potential sources and causes, including intra-articular and extra-articular pathology, and referred pain from other areas (lumbar or groin related pain). To address this, there is a need for a clinical algorithm based on the best available evidence and expert consensus. This algorithm could guide healthcare professionals in assessing and managing patients with hip-related pain, during the diagnosis, test selection, intervention, monitoring, and promoting collaboration among various healthcare providers. This clinical algorithm for hip-related pain is a comprehensive, flexible, adaptable to different settings, and regularly updated to incorporate new research findings. This literature review aims to establish a clinical algorithm specifically for prescribing exercise treatment to patients with hip-related pain, addressing their individual needs and enhancing their overall care.

Associations Between Hip Pathology, Hip and Groin Pain, and Injuries in Hockey Athletes: A Clinical Commentary

Femoroacetabular impingement (FAI), particularly cam morphology, is highly prevalent among elite hockey athletes. Moreover, hip and groin pain has become a common issue in hockey, with approximately 50% of European professional athletes reported to experience a hip or groin problem during a season. While most athletes will not miss training or competition due to this, restricted competitive performance and increased risk of reduced physical and psychological well-being are likely. Recent research suggests that the development of cam morphology is related to the repetitive shear stresses experienced at the hip joint during adolescence from skating. This condition likely increases the potential for intra-articular and extra-articular injuries in these athletes later in their careers. Research also indicates that the hip joint mechanics during forward skating substantially increase the possibility of sustaining a labral tear compared to other sports. Such an injury can increase femoral head movement within the joint, potentially causing secondary damage to the iliofemoral ligament, ligamentum teres and joint capsule. These injuries and the high density of nociceptors in the affected structures may explain the high prevalence of hip and groin pain in hockey athletes. Compensatory adaptations, such as reduced hip strength, stability, and range-of-motion (ROM) likely increase the opportunity for core muscle injuries and hip flexor and adductor injuries. Specifically, the limited hip ROM associated with cam morphology appears to exacerbate the risk of these injuries as there will be an increase in pubic symphysis stress and transverse strain during rotational movements. It is hoped that this article will assist practitioners currently working with hockey athletes to develop evidence-informed monitoring strategies and training interventions, aimed at reducing the incidence and severity of hip and groin problems, ultimately enhancing athlete performance and well-being. Therefore, the purpose of this clinical commentary was to examine current evidence on common hip pathologies in hockey athletes, exploring potential associations between hip and groin pain and the biomechanics of hockey activities.

Level of Evidence

5.

Hip joint contact forces are lower in people with femoroacetabular impingement syndrome during squat tasks

It remains unknown if hip joint forces during squat tasks are altered in people with femoroacetabular impingement syndrome (FAIS). The aim of this study is to compare hip joint forces between people with FAIS and healthy controls during double leg squat and single leg squat tasks and within limbs during a single leg squat task in people with FAIS. Kinematic and kinetic data were collected in eight people with FAIS and eight healthy matched controls using 3D motion capture and force plates. AnyBody Modeling System was used to perform musculoskeletal simulations to estimate hip joint angles, forces, and moments for all participants. Estimates were postprocessed with AnyPyTools and converted into normalized time series to be compared using a 1D statistical nonparametric mapping (SnPM) approach. SnPM with an independent samples t-test model was used to compare people with FAIS to controls, while a paired samples model was used to compare involved to uninvolved limb in people with FAIS. Patients demonstrated lower proximodistal force compared to controls (p < 0.01) and compared to the uninvolved side (p = 0.01) for single leg squat. The smaller joint contact forces in people with FAIS compared to controls could represent a strategy of reduced muscle forces to avoid pain and symptoms during this high demand task. These findings when combined with imaging data could help assess the severity of FAIS on hip related function during higher demand tasks.

PREHAB FAI- Prehabilitation for patients undergoing arthroscopic hip surgery for Femoroacetabular Impingement Syndrome -Protocol for an assessor blinded randomised controlled feasibility study

BACKGROUND

The past decade has seen an exponential growth of minimally invasive surgical procedures. Procedures such as hip arthroscopy have rapidly grown and become the standard of care for patients with Femoroacetabular Impingement Syndrome (FAIS). Although, the results of such procedures are encouraging, a large proportion of patients do not achieve optimal outcomes due to chronicity and deconditioning as a result of delay in diagnosis and increased waiting times amongst other factors. In a recent systematic review and meta-analysis of randomised control trials, moderate certainty evidence supported prehabilitation over standard care in optimising several domains including muscle strength, pain and health related quality of life in patients undergoing orthopaedic surgical interventions. However, the role of prehabilitation in patients with FAI syndrome undergoing hip arthroscopy has received little attention.

AIM

To evaluate the feasibility, suitability, acceptability and safety of a prehabilitation programme for FAI to inform a future definitive randomised control trial to assess effectiveness.

METHODS

A systematically developed prehabilitation intervention based on a literature review and international consensus will be utilised in this study. A mixed methodology encompassing a two-arm randomised parallel study alongside an embedded qualitative component will be used to answer the study objectives. Patients will be recruited from a tertiary referral NHS centre for young adult hip pathology in the UK. Patient reported outcomes such as iHOT-12, Brief Pain Inventory Scale (Short form), Hospital Anxiety and Depression Scale and Patient Global Impression of Change score will be obtained alongside objective measurements such as Muscle Strength and Star Excursion Balance Test at various time points. Outcome measures will be obtained at baseline (prior to prehabilitation intervention), after prehabilitation before surgery, and at 6 weeks+/- 4 weeks and 6 months +/- 4 weeks (planned primary endpoint for definitive RCT) postoperatively when participants attend the research site for clinical care and remotely at 12 months +/- 4 weeks postoperatively. Mean change and 95% CI, and effect size of outcome measures will be used to determine the sample size for a future RCT. For the qualitative component, in depth face-to-face semi-structured interviews with physiotherapists and focus groups with participants will be conducted to assess the feasibility, suitability, and acceptability of the prehabilitation intervention using a predetermined success criteria. All qualitative data will be recorded, transcribed verbatim and thematically analysed.

DISCUSSION

This study will be first of its kind to evaluate a systematically developed prehabilitation intervention for patients with FAIS undergoing hip arthroscopy. This study will provide important preliminary data to inform feasibility of a definitive RCT in the future to evaluate effectiveness of a prehabilitation intervention.

TRIAL REGISTRATION

ISRCTN 15371248, 09/03/2023.

TRIAL PROTOCOL

Version 2.3, 26th June 2023.

Clinical Presentation Differences Among Four Subtypes of Femoroacetabular Impingement: A Case-Control Study

OBJECTIVE

The aims of this study were to assess the psychological, functional, and physical differences between patients with femoroacetabular impingement (FAI) syndrome and individuals who were asymptomatic (controls) to analyze clinical differences among 4 subtypes of FAI (cam type, cam type with labral tear, pincer type, and pincer type with labral tear), to calculate the correlations among the variables described, and to identify risk factors contributing to the hip function variance.

METHODS

A case-control study was conducted at a hospital rehabilitation unit with a cohort of individuals who were asymptomatic (controls) and a cohort of patients with FAI. Sociodemographic characteristics, pain intensity, psychological health status, hip range of motion (RoM), hip isometric strength, and hip function were assessed.

RESULTS

A total of 69 controls and 69 patients with FAI were analyzed. Although sociodemographic characteristics were comparable between samples, poorer hip RoM, strength, and psychological health were found for the cases. FAI subtypes showed no significant pain intensity, psychological health, or RoM differences (except for hip adduction), but hip strength differed among FAI subtypes. Multiple significant correlations between psychological health, pain intensity, RoM, strength, and hip function were found. The variance values of the International Hip Outcome Tool, Hip Outcome Score (HOS) for daily living activities, and HOS for sports activities were partially explained (47.6%, 36.0%, and 21.6%, respectively) on the basis of kinesiophobia, hip strength, self-efficacy, and anxiety.

CONCLUSION

Patients with FAI showed poorer psychological health, hip RoM, and strength than individuals who were asymptomatic and had similar sociodemographic characteristics. FAI subtype influenced the patients' clinical presentations. Hip strength, kinesiophobia, anxiety, and self-efficacy should be targeted for improving hip function, as they have been demonstrated to be important contributors to hip disability.

IMPACT

This study demonstrated that pain catastrophizing, hip strength, and hip adduction differed among FAI subtypes. However, hip function and pain intensity were comparable between FAI subtypes.

Can a clinical assessment predict the functional status progression in patients with femoroacetabular impingement syndrome?

BACKGROUND

Femoroacetabular impingement syndrome (FAIS) is a hip joint motion-related clinical disorder with a triad of symptoms, clinical signs, and imaging findings. However, scientific evidence is still unclear regarding the best treatment for FAIS.

OBJECTIVES

To assess the value of a physical therapy evaluation in predicting the progression of functional status over the subsequent years in patients with FAIS who are candidates for hip arthroscopy surgery.

METHODS

In this case-series study, patients with FAIS, candidates for hip arthroscopy surgery, underwent a standard physical therapy evaluation. Baseline data were collected between 2013 and 2019. In 2020/2021, the patients' functional status was assessed through the International Hip Outcome Tool (iHOT-33). Functional status progression was calculated as the difference between the follow-up and baseline iHOT-33 scores. A multivariate forward stepwise regression analysis was conducted to explore the relationship between baseline characteristics and the functional status progression.

RESULTS

From 353 patients who completed the baseline assessment, 145 completed the iHOT-33 follow-up. The mean (±SD) follow-up time was 58.7 (27.2) months (minimum 12 and maximum 103 months). The iHOT-33 scores increased 20.7 (21.8) points on average, ranging from -39.8 to 76.9 points. Among the 15 potential predictive factors assessed in this study, only baseline iHOT-33 score (β -0.44; -0.061, -0.27), femoral version (β 9.03; 1.36, 16.71), and body mass index (β -0.99; -1.98, -0.01) had the ability to predict the functional status progression.

CONCLUSION

Patients with a lower baseline iHOT-33 score, lower body mass index, and normal femoral version were more likely to increase their functional status after a minimum of one year of follow-up.

Running Alterations Pre- and Postarthroscopy for Femoroacetabular Impingement Syndrome and Labral Tears

ABSTRACT

Freemyer, B, Beeler, D, Crawford, S, Durkin, R, and Stickley, C. Running alterations pre- and postarthroscopy for femoroacetabular impingement syndrome and labral tears. J Strength Cond Res 38(3): 501-509, 2024-Running is essential to sports participation and activity over the lifespan; however, running biomechanics are not fully described in patients with femoroacetabular impingement (FAIS). The purpose was to compare FAIS patient report outcome surveys (PRO) and running biomechanics preoperatively and 6 months postoperatively with controls. Nineteen subjects (FAIS, n = 10 and age-matched controls, n = 9) were included. The UCLA, Hip Outcome Score activity of daily living (HOS ADL ) and sports subscale (HOS SS ), and 3-D running biomechanics were evaluated. Statistical parametric mapping was conducted on biomechanics data. Statistical significance was set at p ≤ 0.05. Femoroacetabular impingement had similar UCLA activity scores compared with controls by 6 months (FAIS: 8.4 ± 1.7, CON: 8.6 ± 2.0, p = 0.80), despite lower HOS ADL (FAIS-Six: 89.3 ± 6.3, CON: 100 ± 0, p = 0.04) and HOS SS (FAIS-Six: 82.6 ± 18.5, CON: 100 ± 0, p = 0.05). The FAIS group had lower knee adduction moments (KAM) around 22-27% of stance ( p = 0.05) and lower sagittal plane ankle power generation during the final 5% of stance compared with the controls ( p = 0.04) preoperatively. The FAIS also had lower vertical ground reaction forces the first 2% of stance ( p = 0.05) and lower KAM from 20 to 30% stance ( p = 0.03) at the postoperative time vs. controls. Femoroacetabular impingement had higher hip external rotation angles the first 5% stance ( p = 0.05) and the last 20% of stance ( p = 0.01) vs. controls. This is the first study to describe FAIS running pre- and postoperatively. Despite higher activity and health 6 months postarthroscopy, the patients with FAIS had altered running biomechanics. Clinicians should consider these findings when creating rehabilitation protocols and during running progressions across the postoperative care of patients with FAIS.

Optimised return to play: high treatment success rate in core muscle injury with surgical release of the anterior tendon of the rectus abdominis muscle and proximal tenotomy of the adductor longus muscle

OBJECTIVES

Core muscle injury is a debilitating condition that causes chronic groin pain in athletes, particularly common in soccer players. The condition is characterised by pain in the inguinal region and can lead to a significant number of absences from high-intensity physical activity. It is caused by repetitive overload without proper counterbalance from the abdominal muscles, hip flexors, and adductors in susceptible athletes. Surgical indications for core muscle injury consider cases where non-surgical treatments have not provided sufficient relief. The aim of this study was to assess the results of surgical intervention for core muscle injury using the technique employed by the Sports Medicine Group of (Institute of Orthopedics and Traumatology of Hospital das Clínicas - Universidade de São Paulo). The procedure involves releasing the anterior portion of the tendon of the rectus abdominis muscle near the pubic symphysis, along with proximal tenotomy of the adductor longus muscle tendon.

METHODS

This study utilised a consecutive historical cohort analysis of the medical records of 45 male athletes, of which, 75.6% were professional soccer players, who underwent surgical treatment between January 1, 2002, and December 31, 2021. The participants included active athletes aged between 18 and 40 years, with a mean age of 23.9 years, and were diagnosed with myotendinous core muscle injury. These athletes experienced pain in the pubic symphysis and adductor tendon region and had previously undergone medical treatment and physical therapy for a duration of three to six months without significant improvement.

RESULTS

The average time for athletes to return to sport after surgery was 135 days, with a majority of participants being soccer and futsal players. The surgical intervention yielded promising results, with a positive correlation between unilateral injuries and the time taken to return to sport. The complication rate was low, at 6.7%. Notably, the rate of symptom resolution was high, at 93.3%. Furthermore, the analysis indicated that the player's position on the field significantly influenced the discharge period, suggesting that the game position plays a role in the recovery process.

CONCLUSION

The combined surgical procedure involving the release of the rectus abdominis tendon and adductor longus muscle tenotomy demonstrates favourable outcomes for athletes with core muscle injury. This study provides strong support for the effectiveness of this surgical approach in managing the condition and offers a potential path to recovery and return to sports activities.

LEVEL OF EVIDENCE: 4

STUDY DESIGN

Cross-sectional study.

The impact of surgical randomised controlled trials on the management of FAI syndrome: a citation analysis

PURPOSE

To identify and assess the clinical impact of randomised controlled trials (RCTs) assessing the surgical management of femoroacetabular impingement syndrome (FAIS) through a citation analysis.

METHODS

MEDLINE, EMBASE and CENTRAL were searched from inception to April 22, 2023 for RCTs assessing the surgical management of FAIS. Study characteristics were directly abstracted from included trials and citation metrics were obtained from the Clarivate Web of Knowledge database on May 19, 2023. The continuous fragility index (CFI) was calculated for eligible outcomes. Univariate regression models were used to explore correlations between total citations per year and various study characteristics.

RESULTS

Ten studies comprising one thousand two hundred ninetypatients were eligible for analysis. Studies were published from 2013 to 2023. Eight countries were represented across various trials with 91% being either North American or European. The mean journal impact factor of published studies was 39.684 (median 2.982; range 1.31-202.73). The mean citation density was 14.17 (range 0.33-48.67). The median CFI was 4.8 (range 1-32.2). Correlation analysis demonstrated strong and statistically significant correlations to study sample size (R = 0.75, p = 0.012), journal impact factor (R = 0.80, p = 0.006) and continuous fragility index (R = 0.95, p = 0.015).

CONCLUSION

Trials assessing the surgical management of FAIS present with a wide range of clinical uptake based on citation density and are published in journals of broadly variable impact factor. Despite promising citation metrics, high-quality evidence on arthroscopy for FAIS is limited to the United States and Europe with an unclear international impact. Future knowledge translation efforts are warranted to maximise the international uptake of evidence regarding arthroscopic management of FAIS.

LEVEL OF EVIDENCE

I.

Return to Play After Femoroacetabular Impingement

PURPOSE OF REVIEW

Femoroacetabular impingement (FAI) is a pathomechanical process whereby abnormal contact between proximal femur and acetabulum at end range of hip motion induces chondrolabral lesions within the hip joint. Surgery followed by a rehabilitation program or physical therapy with possible addition of an intra-articular corticosteroid injection are the two predominant treatments. The majority of authors recognize that a well-designed rehabilitation protocol is essential to achieve good outcomes with both nonoperative and surgical treatment. However, there is little evidence about what is the best rehabilitation protocol and most of the literature available is based on expert level opinion. This current review investigates the recent literature on nonoperative and postoperative rehabilitation protocol and return to play in FAI patients and describes our approach.

RECENT FINDINGS

Historically, rehabilitation protocols for treatment of FAI as well as return to play protocols were based on experts' opinion and low-level evidence studies. In order to improve standardization of protocols and to allow a better comparison in between different protocols, different authors have created standardized rehabilitation protocols with consensus building methods comparing them with other treatment options in high-level evidence trials (FASHIoN trial, etc.). Despite the excellent results reported after nonoperative and post-surgical rehabilitation, and the high RTP rate after FAI treatment, there is a significant variability in between protocols. Further high-level evidence studies are necessary in order to establish a gold standard in rehabilitation and RTP protocols.

Can Clinicians Trust Objective Measures of Hip Muscle Strength From Portable Dynamometers? A Systematic Review With Meta-analysis and Evidence Gap Map of 107 Studies of Reliability and Criterion Validity Using the COSMIN Methodology

OBJECTIVE: To summarize the evidence on reliability and criterion validity of hip muscle strength testing using portable dynamometers. DESIGN: Systematic review with meta-analysis. LITERATURE SEARCH: Five databases were searched from inception to March 2023. STUDY SELECTION CRITERIA: We included studies investigating reliability or criterion validity of hip flexor, extensor, abductor, adductor, or internal/external rotator strength testing with portable dynamometers in injury-free individuals or those with pelvic/lower limb musculoskeletal disorders. DATA SYNTHESIS: We performed meta-analyses for each muscle group, position, and method of fixation. We rated pooled results as sufficient (>75% of studies with correlations ≥0.70), insufficient (>75% of studies with correlations <0.70), or inconsistent (sufficient/insufficient results). We assessed the quality of evidence, created evidence gap maps, and made clinical recommendations. RESULTS: We included a total of 107 studies (reliability 103, validity 14). The intrarater and interrater reliability for hip muscle strength testing across different positions and methods of fixation was sufficient (intraclass correlation coefficient = 0.78-0.96) with low- to high-quality evidence. Criterion validity was less investigated and mostly inconsistent (very low-to moderate-quality evidence) with a wide range of correlations (r = 0.40-0.93). CONCLUSION: Hip muscle strength testing using portable dynamometers is reliable. The use of portable dynamometers as clinical surrogates for measuring strength using an isokinetic dynamometer requires further investigation. Clinicians testing hip muscle strength with portable dynamometers should use external fixation seated for hip flexors, prone or supine for hip extensors, side-lying or supine for abductors and adductors, and prone and seated for internal and external rotators. J Orthop Sports Phys Ther 2023;53(11):655-672. Epub 3 October 2023. doi:10.2519/jospt.2023.12045.

Efficacy and safety of arthroscopy in femoroacetabular impingement syndrome: a systematic review and meta-analysis of randomized clinical trials

This study aimed to compare the efficacy and safety of arthroscopy with physiotherapy or joint lavage in patients with femoroacetabular impingement (FAI). A meta-analysis using PubMed, Embase, Scopus, and the Cochrane Collaboration Library databases was performed in September 2022. We included studies focusing on patients with FAI who underwent arthroscopic surgery versus those who underwent physiotherapy or arthroscopic lavage. The outcomes were functional scores (iHOT-33 and HOS ADL) and adverse events. Randomized clinical trials were included in the study. The risk of bias in each study was assessed according to Cochrane guidelines for clinical trials. The data were combined using Review Manager version 5.4. (PROSPERO CRD42022375273). Six RCTs were included, from a pool of 839 patients (407 females). The iHOT-33 and HOS ADL scales showed significant differences at 12 months in favor of the arthroscopy group (MD, 10.65; 95% CI 6.54-4.76) and (MD, 8.09; 95% CI 3.11-13.07). MCID was not achieved through arthroscopy in functional variables. The rates of osteoarthritis (OR, 6.18; 95% CI 1.06-36.00) and numbness (OR, 73.73; 95% CI 10.00-43.92) were significantly higher in the arthroscopy group. Arthroscopic surgery showed statistical superiority over the control group without exceeding the MCID in most studies; however, the results might have been influenced by secondary variables. Finally, arthroscopic surgery results in a high rate of conversion to osteoarthritis.

Running Mechanics After Repeated Sprints in Femoroacetabular Impingement Syndrome, Cam Morphology, and Controls

BACKGROUND

People with femoroacetabular with femoroacetabular impingement syndrome (FAIS) often report pain during sports involving repeated sprinting. It remains unclear how sports participation influences running biomechanics in individuals with FAIS.

HYPOTHESIS

Changes in running biomechanics and/or isometric hip strength after repeated sprint exercise would be greatest in individuals with FAIS compared with asymptomatic individuals with (CAM) and without cam morphology (Control).

STUDY DESIGN

Controlled laboratory study.

LEVEL OF EVIDENCE

Level 3.

METHODS

Three-dimensional hip biomechanics during maximal running (10 m) and hip strength were measured in 49 recreationally active individuals (FAIS = 15; CAM = 16; Control = 18) before and after repeated sprint exercise performed on a nonmotorized treadmill (8-16 × 30 m). Effects of group and time were assessed for biomechanics and strength variables with repeated-measures analyses of variance. Relationships between hip pain (Copenhagen Hip and Groin Outcome Score) and changes in hip moments and strength after repeated sprint exercise were determined using Spearman's correlation coefficients (ρ).

RESULTS

Running speed, hip flexion angles, hip flexion and extension moments, and hip strength in all muscle groups were significantly reduced from pre to post. No significant between-group differences were observed before or after repeated sprint exercise. No significant relationships (ρ = 0.04-0.30) were observed between hip pain and changes in hip moments or strength in the FAIS group.

CONCLUSION

Changes in running biomechanics and strength after repeated sprint exercise did not differ between participants with FAIS and asymptomatic participants with and without cam morphology. Self-reported pain did not appear to influence biomechanics during running or strength after repeated sprint exercise in participants with FAIS.

CLINICAL RELEVANCE

A short bout of repeated sprinting may not elicit changes in running biomechanics in FAIS beyond what occurs in those without symptoms. Longer duration activities or activities requiring greater hip flexion angles may better provoke pathology-related changes in running biomechanics in people with FAIS.

Posterior Hip Impingement at Maximal Hip Extension in Female Patients With Increased Femoral Version or Increased McKibbin Index and Its Effect on Sports Performance

Background

The location of posterior hip impingement at maximal extension in patients with posterior femoroacetabular impingement (FAI) is unclear.

Purpose

To investigate the frequency and area of impingement at maximal hip extension and at 10° and 20° of extension in female patients with increased femoral version (FV) and posterior hip pain.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Osseous patient-specific 3-dimensional (3D) models were generated of 50 hips (37 female patients, 3D computed tomography) with a positive posterior impingement test and increased FV (defined as >35°). The McKibbin index (combined version) was calculated as the sum of FV and acetabular version (AV). Subgroups of patients with an increased McKibbin index >70° (24 hips) and FV >50° (20 hips) were analyzed. A control group of female participants (10 hips) had normal FV, normal AV, and no valgus deformity (neck-shaft angle, <139°). Validated 3D collision detection software was used for simulation of osseous impingement-free hip extension (no rotation).

Results

The mean impingement-free maximal hip extension was significantly lower in patients with FV >35° compared with the control group (15° ± 15° vs 55° ± 19°; P < .001). At maximal hip extension, 78% of patients with FV >35° had osseous posterior extra-articular ischiofemoral hip impingement. At 20° of extension, the frequency of posterior extra-articular ischiofemoral impingement was significantly higher for patients with a McKibbin index >70° (83%) and for patients with FV >35° (76%) than for controls (0%) (P < .001 for both). There was a significant correlation between maximal extension (no rotation) and FV (r = 0.46; P < .001) as well as between impingement area at 20° of extension (external rotation [ER], 0°) and McKibbin index (0.61; P < .001). Impingement area at 20° of extension (ER, 0°) was significantly larger for patients with McKibbin index >70° versus <70° (251 vs 44 mm²; P = .001).

Conclusion

The limited hip extension found in our study could theoretically affect the performance of sports activities such as running, ballet dancing, or lunges. Therefore, although not examined directly in this study, these activities are not advisable for these patients. Preoperative evaluation of FV and the McKibbin index is important in female patients with posterior hip pain before hip preservation surgery (eg, hip arthroscopy).

Single-Leg Squat Test in the Clinical Setting Does Not Discriminate Patients With Femoroacetabular Impingement Syndrome From Asymptomatic Individuals

CONTEXT

Laboratorial 3-dimensional kinematic analyses have shown changes in the single-leg squat's (SLS) pattern of patients with femoroacetabular impingement syndrome (FAIS). However, it is unknown whether clinicians are able to detect these changes using 2-dimensional kinematics.

OBJECTIVE

To compare the frontal plane 2-dimensional kinematics of patients with FAIS and asymptomatic individuals in the SLS test performed in a clinical setting.

DESIGN

Case-control study.

SETTING

Physical therapy clinic.

PARTICIPANTS

Twenty men with bilateral FAIS and 20 asymptomatic men.

MAIN OUTCOME MEASURES

Two-dimensional kinematic analysis was collected in the frontal plane during the execution of the SLS test. The outcomes were squat depth, pelvic drop (pelvis angle relative to the horizontal plane), hip adduction (femur angle relative to the pelvis), and knee valgus (femur angle relative to the tibia).

RESULTS

Most and least painful limbs of patients with FAIS had squat depth (9.8% [2.9%] and 9.5% [3.1%] of height), pelvic drop (4.2° [3.9°] and 3.7° [4.2°]), hip adduction (74.9° [5.8°] and 75.9° [5.7°]), and knee valgus (4.0° [11.0°] and 5.0° [9.9°]) similar to asymptomatic individuals (9.0% [2.3%], 4.8° [2.6°], 73.7° [4.9°], and -1.7° [8.5°]; P > .05 for all).

CONCLUSION

The frontal plane 2-dimensional kinematic analysis of the SLS test in the clinical setting is not able to distinguish patients with FAIS from asymptomatic individuals.

Measurement of the normal contralateral hip flexion angle and posterior pelvic tilt angle using a pelvic guide pin in total hip arthroplasty

BACKGROUND

We aimed to measure the posterior pelvic tilt angle at maximum hip flexion and hip flexion range of motion at the femoroacetabular joint using a pelvic guide pin and to examine the difference in flexion range of motion when determined by a physical therapist and under anesthesia.

METHODS

Data of 83 consecutive patients undergoing primary unilateral total hip arthroplasty were assessed. Using a pin inserted into the iliac crest to define the cup placement angle under anesthesia before and after total hip arthroplasty, the posterior pelvic tilt angle was determined as the change in pin tilt from the supine position to maximum hip flexion. Flexion range of motion under anesthesia was calculated as the difference in the angle between the trunk and thigh at maximum flexion and the posterior pelvic tilt angle. Flexion range of motion with a fixed pelvis measured preoperatively by a physical therapist was compared to that under anesthesia. A goniometer was used for all measurements and the number of measurements was one.

FINDINGS

Mean posterior pelvic tilt angle of the pin inserted into the pelvis under anesthesia was 15.8° ± 5.3° (3°-26°) preoperatively and 12.1° ± 4.9° (3°-26°) postoperatively. Mean flexion range of motion under anesthesia was 109.4° ± 6.9° (88°-126°) and that measured by a physical therapist was 101.1° ± 8.2° (80°-120°); the difference was significant (9.7°; p < 0.01).

INTERPRETATION

These results highlight the difficulty in accurately determining hip flexion angles without the use of special devices and may help surgeons and physical therapists recognize and address this issue.

Does femoroacetabular impingement syndrome affect range of motion? A systematic review with meta-analysis

BACKGROUND

It is unclear whether femoroacetabular impingement syndrome (FAIS) affect hip range of motion (ROM).

SOURCES OF DATA

We performed a systematic review with meta-analysis searching six electronic databases from inception to March 21, 2022. We included studies assessing hip ROM in FAIS, FAI morphology without symptoms (FAIm), and healthy controls. Mean differences between groups were measured in ROM degrees with 95% confidence interval (CI).

AREAS OF AGREEMENT

A total of 17 studies (1702 hips) were included. Comparison of FAIS patients versus healthy controls showed that hip ROM was clinically and statistically reduced in FAIS for internal rotation (90° hip flexion, -8.01°, 95% CI: -11.21, -4.90; 0° hip flexion -6.38°, 95% CI: -9.79, -2.97); adduction (90° hip flexion, -4.74°, 95% CI: -8.13, -1.34); flexion (-5.41°, 95% CI: -7.05, -3.49), abduction (0° hip flexion, -5.76°, 95% CI: -8.38, -3.23), and external rotation (90° hip flexion, -3.5°, 95% CI: -5.32, -1.67) ranging from low to high certainty of evidence. Comparison of FAIm versus healthy controls showed no statistically significant differences in any direction of movement, albeit with uncertainty of evidence.

AREAS OF CONTROVERSY

The certainty of evidence was unclear, particularly for asymptomatic FAIm.

GROWING POINTS

Hip ROM may be reduced in all directions except extension in FAIS compared to controls. Hip ROM may not be restricted in asymptomatic FAIm.

AREAS TIMELY FOR DEVELOPING RESEARCH

Further studies are needed to resolve the uncertainty of evidence about ROM restrictions in asymptomatic FAIm compared to healthy controls.

Limited External Rotation and Hip Extension Due to Posterior Extra-articular Ischiofemoral Hip Impingement in Female Patients With Increased Femoral Anteversion: Implications for Sports, Sexual, and Daily Activities

BACKGROUND

Posterior femoroacetabular impingement (FAI) is poorly understood. Patients with increased femoral anteversion (FV) exhibit posterior hip pain.

PURPOSE

To correlate hip impingement area with FV and with combined version and to investigate frequency of limited external rotation (ER) and hip extension (<40°, <20°, and <0°) due to posterior extra-articular ischiofemoral impingement.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Osseous patient-specific three-dimensional (3D) models based on 3D computed tomography scans were generated of 37 female patients (50 hips) with positive posterior impingement test (100%) and increased FV >35° (Murphy method). Surgery was performed in 50% of patients (mean age, 30 years; 100% female). FV and acetabular version (AV) were added to calculate combined version. Subgroups of patients (24 hips) with increased combined version >70° and patients (9 valgus hips) with increased combined version >50° were analyzed. The control group (20 hips) had normal FV, normal AV, and no valgus. Bone segmentation was performed to generate 3D models of every patient. Validated 3D collision detection software was used for simulation of impingement-free hip motion (equidistant method). Impingement area was evaluated in combined 20° of ER and 20° of extension.

RESULTS

Posterior extra-articular ischiofemoral impingement occurred between the ischium and the lesser trochanter in 92% of patients with FV >35° in combined 20° of ER and 20° of extension. Impingement area in combined 20° of ER and 20° of extension was larger with increasing FV and with higher combined version; correlation was significant (P < .001, r = 0.57, and r = 0.65). Impingement area was significantly (P = .001) larger (681 vs 296 mm2) for patients with combined version >70° (vs <70°, respectively) in combined 20° of ER and 20° of extension. All symptomatic patients with increased FV >35° (100%) had limited ER <40°, and most (88%) had limited extension <40°. The frequency of posterior intra- and extra-articular hip impingement of symptomatic patients (100% and 88%, respectively) was significantly (P < .001) higher compared with the control group (10% and 10%, respectively). The frequency of patients with increased FV >35° with limited extension <20° (70%) and patients with limited ER <20° (54%) was significantly (P < .001) higher compared with the control group (0% and 0%, respectively). The frequency of completely limited extension <0° (no extension) and ER <0° (no ER in extension) was significantly (P < .001) higher for valgus hips (44%) with combined version >50° compared with patients with FV >35° (0%).

CONCLUSION

All patients with increased FV >35° had limited ER <40°, and most of them had limited extension <20° due to posterior intra- or extra-articular hip impingement. This is important for patient counselling, for physical therapy, and for planning of hip-preservation surgery (eg, hip arthroscopy). This finding has implications and could limit daily activities (long-stride walking), sexual activity, ballet dancing, and sports (eg, yoga or skiing), although not studied directly. Good correlation between impingement area and combined version supports evaluation of combined version in female patients with positive posterior impingement test or posterior hip pain.

Change in functional biomechanics following a targeted exercise intervention in patients with acetabular retroversion and femoroacetabular impingement syndrome

BACKGROUND

Acetabular retroversion is a form of hip dysplasia that may cause femoroacetabular impingement syndrome (FAIS), leading to pain and restricted hip range of motion. An exercise intervention aiming at altering pelvis tilt and related functional biomechanics may be a useful first-line intervention for patients who are not eligible for surgical repositioning.

RESEARCH QUESTION

Does squat and gait biomechanics change following an 8-week targeted exercise program in individuals with symptomatic acetabular retroversion and FAIS?

METHODS

This prospective intervention study used participants as their own controls. Examinations were conducted at three time-points: T1 baseline; T2 following an 8-week control period; T3 after 8 weeks' intervention. At each time-point, three-dimensional motion analysis of a deep squat and level gait was performed, and pain intensity was recorded using a numerical rating scale (NRS 0-10). The intervention consisted of a home-exercise program to improve core stability and pelvic movement. Differences in waveforms between time-points across pelvis and lower-limb biomechanics were evaluated using statistical parametric mapping. Delta (Δ, differences between T1-T2 and T2-T3) was used to evaluate changes in spatiotemporal gait parameters and pain.

RESULTS

Nineteen patients (18 females), mean age 22.6 (SD 4.5) years, BMI (kg/m2) 23.0 (SD 4.1), were included. Changes (Δ T1-T2 vs. Δ T2-T3) in squat biomechanics were observed as: (i) decreased anterior pelvic tilt, (ii) deeper vertical pelvis position, and (iii) increased knee flexion angle. Contrary, no significant changes in gait biomechanics, Δ walking speed, Δ step length, or NRS for pain were found.

SIGNIFICANCE

Following a targeted exercise intervention, participants were able to squat deeper, potentially allowing better hip function. The deepened squat position was accompanied by increased knee flexion and reduced anterior pelvic tilt. Gait biomechanics and patient-reported pain remained unchanged post-intervention. These findings are important for future design of exercise interventions targeting pelvic tilt in symptomatic individuals.

Femoral impingement in maximal hip flexion is anterior-inferior distal to the cam deformity in femoroacetabular impingement patients with femoral retroversion : implications for hip arthroscopy

AIMS

Femoroacetabular impingement (FAI) patients report exacerbation of hip pain in deep flexion. However, the exact impingement location in deep flexion is unknown. The aim was to investigate impingement-free maximal flexion, impingement location, and if cam deformity causes hip impingement in flexion in FAI patients.

METHODS

A retrospective study involving 24 patients (37 hips) with FAI and femoral retroversion (femoral version (FV) < 5° per Murphy method) was performed. All patients were symptomatic (mean age 28 years (SD 9)) and had anterior hip/groin pain and a positive anterior impingement test. Cam- and pincer-type subgroups were analyzed. Patients were compared to an asymptomatic control group (26 hips). All patients underwent pelvic CT scans to generate personalized CT-based 3D models and validated software for patient-specific impingement simulation (equidistant method).

RESULTS

Mean impingement-free flexion of patients with mixed-type FAI (110° (SD 8°)) and patients with pincer-type FAI (112° (SD 8°)) was significantly (p < 0.001) lower compared to the control group (125° (SD 13°)). The frequency of extra-articular subspine impingement was significantly (p < 0.001) increased in patients with pincer-type FAI (57%) compared to cam-type FAI (22%) in 125° flexion. Bony impingement in maximal flexion was located anterior-inferior at femoral four and five o'clock position in patients with cam-type FAI (63% (10 of 16 hips) and 37% (6 of 10 hips)), and did not involve the cam deformity. The cam deformity did not cause impingement in maximal flexion.

CONCLUSION

Femoral impingement in maximal flexion was located anterior-inferior distal to the cam deformity. This differs to previous studies, a finding which could be important for FAI patients in order to avoid exacerbation of hip pain in deep flexion (e.g. during squats) and for hip arthroscopy (hip-preservation surgery) for planning of bone resection. Hip impingement in flexion has implications for daily activities (e.g. putting on shoes), sports, and sex.Cite this article: Bone Joint Res 2023;12(1):22-32.

Return to sport after conservative versus surgical treatment for pubalgia in athletes: a systematic review

Background

To assess the time required to return to sport (RTS) after conservative versus surgical treatment in athletes for pubalgia.

Methods

The PRISMA guidelines were followed. Pubmed, SportDiscus and Web of Science were last accessed on September 2022. All the studies investigating the time to RTS after conservative versus surgical treatment in athletes for pubalgia.

Results

In total, 33 studies were selected for full text assessment, and 10 studies were included in the qualitative analysis. Seven studies reported data on conservative management, two on surgical management and one compared both. A total of 468 subjects were included for analysis. 58.7% (275 of 468) were soccer players, 5.9% (28 of 468) runners, and 3.8% (18 of 468) hockey players. Two studies did not specify the type of sport. The quality of the studies detailing the results of conservative management was higher than surgical procedures.

Conclusion

This review highlights that individuals undergoing surgery for pubalgia may return to sport earlier than those receiving conservative treatment. However, conservative management should be considered before surgical treatment is indicated.

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

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

Do femoral version abnormalities play a role in hip function of patients with hip pain?

BACKGROUND

A high prevalence of femoral version abnormalities has been observed in hip pain patients, with impact on hip range of motion and muscle strength that should be elucidated.

METHODS

Cross-sectional study. Thirty-one patients with hip pain (16 men and 15 female) were subjected to Biplanar X-Rays to quantify femoral version using three-dimensional measurements. The 62 hips were divided into normal version (10-20°, n = 18), anteverted (>20°, n = 19), and retroverted (<10°, n = 25). Joint range of motion for flexion, internal rotation, and external rotation was assessed through digital goniometry. Maximal isometric hip strength (flexion, extension, internal rotation, external rotation at 0° and 30°, abduction, adduction) was evaluated through hand-held dynamometry. Hip rotation index was calculated as external rotation minus internal rotation.

FINDINGS

Anteverted hips had greater internal rotation, while retroverted hips had greater external rotation (p = 0.001). Anteverted hips were weaker than retroverted hips for external rotation at 30° (p < 0.001), abduction (p = 0.006) and adduction (p < 0.001), and weaker than normal version hips for extension (p = 0.018). All three groups had different rotation index: retroverted>normal>anteverted (p < 0.001). The ordinal logistic regression found higher values of rotation index with higher probability of being retroverted (common odds ratio = 1.20). There was a strong correlation between femoral version group and rotation index (r_S = 0.76, p < 0.001). There was probability >70% of a hip being anteverted if the rotation index was <11°, and being retroverted if the index was >40°.

INTERPRETATION

Range of motion and muscle strength differed in hips with different femoral versions. The hip rotation index was a strong femoral version predictor.

Correlation between the range of rotation of the hip and the radiographic signs of cam and pincer morphology in femoroacetabular impingement syndrome

Objective

To determine whether hip rotation correlates with the radiographic signs of cam or pincer deformity after hip arthroscopy in patients with femoroacetabular impingement syndrome.

Materials and Methods

This was a single-center retrospective study of data collected between 2014 and 2017. The study sample included 65 patients between 18 and 55 years of age who underwent hip arthroscopy for the treatment of unilateral femoroacetabular impingement. The following data were collected for the periods prior to and six months after surgery range of medial and lateral rotation of the hip; measures on anteroposterior X-rays of the pelvis obtained in the standing position and on ateral X-rays in the Ducroquet profile view; and score on the 33-item International Hip Outcome Tool.

Results

Mean preoperative and postoperative values were as follows: 19.26 ± 10.39° and 30.95 ± 3.52°, respectively, for medial rotation of the hip (p < 0.001); 73.85 ± 6.62° and 68.12 ± 5.04°, respectively, for the anteroposterior alpha angle (p < 0.001); 56.97 ± 6.09° and 50.61 ± 5.39°, respectively, for the lateral alpha angle (p < 0.001); and 0.17 ± 0.11 and 0.07 ± 0.08, respectively, for the acetabular retroversion index (p < 0.001). The crossover sign was identified in 75.4% of the patients before surgery and in 44.6% after (p < 0.001). Although there was an increase in the range of hip rotation and an improvement in radiographic parameters after arthroscopy, we detected no direct correlation between the two.

Conclusion

Hip arthroscopy can improve medial rotation of the hip, as well as reducing cam and pincer deformities, in patients with femoroacetabular impingement syndrome. However, those findings do not appear to be directly correlated.

Hip joint motion does not change one year after arthroscopic osteochondroplasty in patients with femoroacetabular impingement evaluated with dynamic radiostereometry

Purpose

Dynamic radiostereometric analysis (dRSA) enables precise non-invasive three-dimensional motion-tracking of bones for assessment of joint kinematics. Hereby, the biomechanical effects of arthroscopic osteochondroplasty of the hip (ACH) can be evaluated in patients with femoroacetabular impingement (FAI).

The aim was to investigate the pre- and postoperative range of motion (ROM) and the CT bone volume removed (BV) after ACH. We hypothesize increase in ROM 1 year after surgery.

Methods

Thirteen patients (6 female) with symptomatic FAI were included prospectively. The patient’s hips were CT-scanned and CT-bone models were created. Preoperative dRSA recordings were acquired during passive flexion to 90°, adduction, and internal rotation (FADIR). ACH was performed, CT and dRSA were repeated 3 months and 1 year postoperatively. Hip joint kinematics before, and 3 months and 1 year after ACH were compared pairwise. The bone volume removal was quantified and compared to change in ROM.

Results

Mean hip internal rotation, adduction and flexion were all unchanged after ACH at 1-year follow-up (p > 0.84). HAGOS scores revealed improvement of quality of life (QOL) from 32 to 60 (p = 0.02). The BV was between 406 and 1783 mm³ and did not correlate to post-operative ROM.

Conclusions

ACH surgery in FAI patients had no impact of ROM at 1-year follow-up. QOL improved significantly. This indicates that the positive clinical effects reported after ACH might be a result of reduced labral stress and cartilage pressure during end-range motion rather than increased ROM.

Level of evidence

Therapeutic prospective cohort study, level II.

Biomechanics of Cam Femoroacetabular Impingement: A Systematic Review

PURPOSE

To assess how biomechanical gait parameters (kinematics, kinetics, and muscle force estimations) differ between patients with cam-type femoroacetabular impingement (FAI) and healthy controls, through a systematic search.

METHODS

A systematic review of the literature from PubMed, Scopus, and Medline and EMBASE via OVID SP was undertaken from inception to April 2020 using PRISMA guidelines. Studies that described kinematics, kinetics, and/or estimated muscle forces in cam-type FAI were identified and reviewed.

RESULTS

The search strategy identified 404 articles for evaluation. Removal of duplicates and screening of titles and abstracts resulted in full-text review of 37 articles, with 12 meeting inclusion criteria. The 12 studies reported biomechanical data on a total of 173 cam-FAI (151 cam-specific, 22 mixed-type) patients and 177 healthy age-, sex-, and body mass index-matched controls. Patients with cam FAI had reduced hip sagittal plane range of motion (mean difference -3.00° [-4.10, -1.90], P < .001), reduced hip peak extension angles (mean difference -2.05° [-3.58, -0.53] , P = .008), reduced abduction angles in the terminal phase of stance, and reduced iliacus and psoas muscle force production in the terminal phase of stance compared to the control groups. Cam FAI cohorts walked at a slower speed compared with controls.

CONCLUSIONS

In conclusion, patients with cam-type FAI exhibit altered sagittal and frontal plane kinematics as well as altered muscle force production during level gait compared to controls. These findings will help guide future research into gait alterations in FAI and how such alterations may contribute to pathologic progression and furthermore, how such alterations can be modified for therapeutic benefit.

LEVEL OF EVIDENCE

Systematic review of Level III studies.

The effects of sex and landing task on hip mechanics

Prevalence of femoroacetabular impingement syndrome is common in cutting sports. A first step to understanding the relationship between cutting sports and the development of femoroacetabular impingement is to investigate hip joint contact forces during such tasks. The purpose of this study was to explore sex and task differences in hip joint contact forces, estimated through musculoskeletal modeling, during single-leg drop landings and land-and-cuts. Kinematics and ground reaction forces were obtained from 38 adults performing drop landings and land-and-cut tasks. Simulations were performed in OpenSim to estimate lower extremity muscle forces and hip joint contact forces. Statistical parametric mapping was used to compare hip joint force waveforms between sex and task. There were no sex differences in hip joint forces, but landing trials were characterized by increased hip joint forces compared to land-and-cut trials. The hip joint force estimates obtained the current study could be used in future finite element models that incorporate bone growth models to understand the development of femoroacetabular impingement and design possible compensatory exercises.

Physical impairments in longstanding hip and groin pain: Cross-sectional comparison of patients with hip-related pain or non-hip-related groin pain and healthy controls

OBJECTIVES

To compare physical impairments between patients with hip-related pain and those with non-hip-related groin pain, and to compare both patient groups with healthy controls.

DESIGN

Cross-sectional.

PARTICIPANTS

Eighty-one hip and groin pain patients were consecutively included and categorized into having hip-related pain or non-hip-related groin pain. Twenty-eight healthy controls were recruited.

SETTINGS

Tertiary care.

MAIN OUTCOME MEASURES

All participants performed physical impairment testing including hip ROM, muscle function, and functional tasks. An analysis of covariates was used for analysis between patients groups and controls.

RESULTS

Patients with hip-related pain showed reduced hip ROM in internal rotation compared to patients with non-hip-related groin pain and controls (p ≤ 0.026, d -0.65; -0.97). No differences in muscle function or performance in functional tasks were observed between patients with hip-related pain and those with non-hip-related groin pain (p ≥ 0.136, d 0.00; 0.68). Both patient groups had worse muscle function and worse performance in functional tasks compared to controls (p ≤ 0.048, d -0.67; -1.83).

CONCLUSIONS

Both patients with and without hip-related pain had worse muscle function and worse performance in functional tasks compared to matched controls but no differences were observed between the patient groups. Only patients with hip-related pain had reduced ROM in internal rotation.

Subject-Specific Modeling of Femoral Torsion Influences the Prediction of Hip Loading During Gait in Asymptomatic Adults

Hip osteoarthritis may be caused by increased or abnormal intra-articular forces, which are known to be related to structural articular cartilage damage. Femoral torsional deformities have previously been correlated with hip pain and labral damage, and they may contribute to the onset of hip osteoarthritis by exacerbating the effects of existing pathoanatomies, such as cam and pincer morphologies. A comprehensive understanding of the influence of femoral morphotypes on hip joint loading requires subject-specific morphometric and biomechanical data on the movement characteristics of individuals exhibiting varying degrees of femoral torsion. The aim of this study was to evaluate hip kinematics and kinetics as well as muscle and joint loads during gait in a group of adult subjects presenting a heterogeneous range of femoral torsion by means of personalized musculoskeletal models. Thirty-seven healthy volunteers underwent a 3D gait analysis at a self-selected walking speed. Femoral torsion was evaluated with low-dosage biplanar radiography. The collected motion capture data were used as input for an inverse dynamics analysis. Personalized musculoskeletal models were created by including femoral geometries that matched each subject’s radiographically measured femoral torsion. Correlations between femoral torsion and hip kinematics and kinetics, hip contact forces (HCFs), and muscle forces were analyzed. Within the investigated cohort, higher femoral antetorsion led to significantly higher anteromedial HCFs during gait (medial during loaded stance phase and anterior during swing phase). Most of the loads during gait are transmitted through the anterior/superolateral quadrant of the acetabulum. Correlations with hip kinematics and muscle forces were also observed. Femoral antetorsion, through altered kinematic strategies and different muscle activations and forces, may therefore lead to altered joint mechanics and pose a risk for articular damage. The method proposed in this study, which accounts for both morphological and kinematic characteristics, might help in identifying in a clinical setting patients who, as a consequence of altered femoral torsional alignment, present more severe functional impairments and altered joint mechanics and are therefore at a higher risk for cartilage damage and early onset of hip osteoarthritis.

Reliability of hip muscle strength measured in principal and intermediate planes of movement

BACKGROUND

Muscle strength testing is widely used in clinical and athletic populations. Commercially available dynamometers are designed to assess strength in three principal planes (sagittal, transverse, frontal). However, the anatomy of the hip suggests muscles may only be recruited submaximally during tasks performed in these principal planes.

OBJECTIVE

To evaluate the inter-session reliability of maximal isometric hip strength in the principal planes and three intermediate planes.

METHODS

Twenty participants (26.1 ± 2.7 years, 50% female) attended two testing sessions 6.2 ± 1.8 days apart. Participants completed 3-5 maximal voluntary isometric contractions for hip abduction, adduction, flexion, extension, and internal and external rotation measured using a fixed uniaxial load cell (custom rig) and commercial dynamometer (Biodex). Three intermediate hip actions were also tested using the custom rig: extension with abduction, extension with external rotation, and extension with both abduction and external rotation.

RESULTS

Moderate-to-excellent intraclass correlation coefficients were observed for all principal and intermediate muscle actions using the custom rig (0.72-0.95) and the Biodex (0.85-0.95). The minimum detectable change was also similar between devices (custom rig = 11-31%; Biodex = 9-20%). Bland-Altman analysis revealed poor agreement between devices (range between upper and lower limits of agreement = 77-131%).

CONCLUSIONS

Although the custom rig and Biodex showed similar reliability, both devices may lack the sensitivity to detect small changes in hip strength commonly observed following intervention.

Posterior Extra-articular Ischiofemoral Impingement Can Be Caused by the Lesser and Greater Trochanter in Patients With Increased Femoral Version: Dynamic 3D CT-Based Hip Impingement Simulation of a Modified FABER Test

Background:

Posterior extra-articular hip impingement has been described for valgus hips with increased femoral version (FV). These patients can present clinically with lack of external rotation (ER) and extension and with a positive posterior impingement test. But we do not know the effect of the combination of deformities, and the impingement location in early flexion is unknown.

Purpose:

To evaluate patient-specific 3-dimensional computed tomography (3D CT) scans of hips with increased FV and control hips for differences in range of motion, location and prevalence of osseous posterior intra- and extra-articular hip impingement.

Study Design:

Case series; Level of evidence, 4.

Methods:

Osseous 3D models based on segmentation of 3D CT scans were analyzed for 52 hips (38 symptomatic patients) with positive posterior impingement test and increased FV (>35°). There were 26 hips with an increased McKibbin instability index >70 (unstable hips). Patients were mainly female (96%), with an age range of 18 to 45 years. Of them, 21 hips had isolated increased FV (>35°); 22 hips had increased FV and increased acetabular version (AV; >25°); and 9 valgus hips (caput-collum-diaphyseal angle >139°) had increased FV and increased AV. The control group consisted of 20 hips with normal FV, normal AV, and no valgus (caput-collum-diaphyseal angle <139°). Validated 3D CT–based collision detection software for impingement simulation was used to calculate impingement-free range of motion and location of hip impingement. Surgical treatment was performed after the 3D CT–based impingement simulation in 27 hips (52%).

Results:

Hips with increased FV had significantly (P < .001) decreased extension and ER at 90° of flexion as compared with the control group. Posterior impingement was extra-articular (92%) in hips with increased FV. Valgus hips with increased FV and AV had combined intra- and extra-articular impingement. Posterior hip impingement occurred between the ischium and the lesser trochanter at 20° of extension and 20° of ER. Impingement was located between the ischium and the greater trochanter or intertrochanteric area at 20° of flexion and 40° of ER, with a modification of the flexion-abduction-ER (FABER) test.

Conclusion:

Posterior extra-articular ischiofemoral hip impingement can be caused by the lesser and greater trochanter or the intertrochanteric region. We recommend performing the modified FABER test during clinical examination in addition to the posterior impingement test for female patients with high FV. In addition, 3D CT can help for surgical planning, such as femoral derotation osteotomy and/or hip arthroscopy or resection of the lesser trochanter.

Influence of simulated hip muscle weakness on hip joint forces during deep squatting

This study aimed to determine the effects of simulated hip muscle weakness on changes in hip joint forces during deep squat motion. Ten healthy individuals performed squat motion at three different positions (0° foot angle [N-squat], 10° toe-in [IN-squat], and 30° toe-out [OUT-squat]). A scaled musculoskeletal model for each participant was used to calculate the muscle and hip joint forces. For each hip muscle, models of full strength, mild muscle weakness (15% decrease), and severe muscle weakness (30% decrease) were created. The muscles affecting the hip joint forces were identified, and the rate of change in the joint forces was compared among the three squat conditions. The anterior hip joint force was increased in the muscle weakness models of the inferior gluteus maximus (iGlutMax) and iGlutMax+deep external rotator (ExtRot) muscles. With 30% muscle weakness of these muscles, statistically significant differences in the rate of increase in the anterior joint force were observed in the following order: IN-squat (iGlutMax, 29.5%; iGlutMax+ExtRot, 41.4%), N-squat (iGlutMax, 18.3%; iGlutMax+ExtRot, 27.8%), and OUT-squat (iGlutMax, 5.6%; iGlutMax+ExtRot, 9.3%). OUT-squat may be recommended to minimize the increase in hip joint forces if accompanied by hip muscle weakness.

Morphological Changes of the Hip Commonly Associated With Femoroacetabular Impingement Are Not Correlated With Rotational Range of Hip Motion in Elite Soccer Athletes

BACKGROUND

Morphological changes characteristic of femoroacetabular impingement (FAI) are common in soccer players. However, the clinical relevance of such anatomical variations is still not well-defined.

HYPOTHESIS

We hypothesized that high alpha angle values and/or acetabular retroversion index (ARI) are correlated with rotational range of motion (ROM) of the hip and that there are clinical-radiological diferences between the dominant lower limb (DLL) and nondominant lower limb (NDLL) in professional soccer players.

STUDY DESIGN

Cross-sectional.

LEVEL OF EVIDENCE

Level 3.

METHODS

A total of 59 male professional soccer players (average age 25.5 years, range 18-38 years) were evaluated in the preseason. As main outcome measures, we evaluated the alpha angle and the ARI and hip IR and ER ROM with radiographic analysis.

RESULTS

The measurements taken on DLL and NDLL were compared and a significant difference was found between the sides in the ER (P = 0.027), where the DLL measures were 1.54° (95% CI, 0.18-2.89) greater than the NDLL. There were no significant differences between the sides in the measures of IR (P > 0.99), total ROM (P = 0.07), alpha angle (P = 0.250), and ARI (P = 0.079). The correlations between the rotation measurements and the alpha angle in each limb were evaluated and the coefficient values showed no correlation; so also between the ARI and rotation measures.

CONCLUSION

Morphological changes of the femur or acetabulum are not correlated with hip IR and ER ROM in male professional soccer players. ER on the dominant side was greater than on the nondominant side. There was no significant difference in the other measurements between sides.

CLINICAL RELEVANCE

In clinical practice, it is common to attribute loss of hip rotational movement to the presence of FAI. This study shows that anatomical FAI may not have a very strong influence on available hip rotational movement in professional soccer athletes.

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.

Pericapsular hip muscle activity in people with and without femoroacetabular impingement. A comparison in dynamic tasks

OBJECTIVES

Compare anterior pericapsular muscle activity between individuals with and without femoroacetabular impingement syndrome (FAIS) during dynamic tasks, to investigate whether muscle activity is consistent with a role in retracting the capsule to prevent impingement and active restraint of the femoral head in walking.

DESIGN

Cross-sectional.

SETTING

University-laboratory.

PARTICIPANTS

Thirteen athletes with FAIS and 13 pain-free controls.

MAIN OUTCOME MEASURES

Muscle activity was recorded using fine-wire (Iliocapsularis, iliacus and anterior gluteus minimus) and surface (rectus femoris) electromyography (EMG), during three hip flexion tasks (active and assisted hip flexion; squatting) and four walking trials.

RESULTS

Iliocapsularis EMG amplitude was no different between active and assisted hip flexion tasks around 90° of hip flexion in FAIS. There was no difference in EMG between groups in squatting. The pattern of burst activity preceding peak hip extension in iliacus, iliocapsularis, and anterior gluteus minimus was similar in both groups during walking.

CONCLUSION

In FAIS, similar activation of iliocapsularis during active and assisted hip flexion, despite reduced flexion torque demand in the latter, suggests a role in capsular retraction or enhanced hip joint protection. Pericapsular muscle activity in advance of peak hip extension during walking is consistent with a proposed contribution to femoral head control.

Physiotherapy as an Initial Treatment Option for Femoroacetabular Impingement: A Systematic Review of the Literature and Meta-analysis of 5 Randomized Controlled Trials

BACKGROUND

Femoroacetabular impingement is a common and debilitating source of hip pain in young adults. Although physiotherapy is used as a mainstay of nonoperative care for femoroacetabular impingement, the evidence regarding different physiotherapy practices is poorly understood.

PURPOSE

To collect and synthesize the best available evidence and arrive at a summary estimate of treatment effect for the utility of physiotherapy in the management of femoroacetabular impingement.

STUDY DESIGN

Meta-analysis.

METHODS

A systematic review was performed on February 2, 2019, of PubMed, EMBASE, and Cochrane Library databases using "femoroacetabular impingement OR hip pain" and "physiotherapy OR nonoperative management" and their synonyms as search terms. Central treatment themes were identified across protocols, and pooled analyses were conducted to assess for differences in patient-reported outcome measures across these themes.

RESULTS

A total of 5 randomized controlled trials met our inclusion criteria. The studies included 124 patients with a mean age of 35 years, of whom 24% were male. The average follow-up was 9.4 weeks (range, 6-12 weeks), and the follow-up rate across all participants was 86%. Among these 5 studies, 4 studies used a physiotherapy protocol that focused on core strengthening versus no core strengthening, 4 studies compared active strengthening versus passive modalities, and 3 studies compared supervised versus unsupervised physiotherapy. Pooled analysis across all studies demonstrated improved outcomes in the treatment groups compared with the controls (standardized mean difference [SMD], 0.76; 95% CI, 0.38-1.13; P < .0001). Core strengthening (SMD, 0.82; 95% CI, 0.39-1.26; P = .0002), active physiotherapy (SMD, 0.70; 95% CI, 0.29-1.10; P = .0008), and supervised physiotherapy (SMD, 0.58; 95% CI, 0.14-1.03; P = .01) were found to result in statistically significant improvements in functional outcomes compared with no core strengthening, passive modalities, and unsupervised care, respectively.

CONCLUSION

Supervised physiotherapy programs focusing on active strengthening and core strengthening are more effective than unsupervised, passive, and non-core focused programs. Future studies with longer term follow-up and validated femoroacetabular impingement specific outcome measures are required to determine prognostic factors for success with nonoperative care as well as to determine the ideal patient profile and structured rehabilitation protocol.

Biomechanics during cross-body lunging in individuals with and without painful cam and/or pincer morphology

BACKGROUND

Femoroacetabular impingement is a patho-mechanical hip condition that can lead to restrictions in hip motion, particularly in end-range hip flexion, adduction and/or internal rotation. Radiographic evidence of femoroacetabular impingement - cam and/or pincer morphology - is prevalent in the general and athletic populations. There is, however, a lack of studies that have analyzed the performance of sport-specific movements in people possessing these morphologies. Therefore, the purpose of this study was to compare cross-body lunge biomechanics between individuals with and without painful cam and/or pincer morphology.

METHODS

This was an exploratory, cross-sectional study where nine participants with cam and/or pincer morphology and symptoms, thirteen participants with asymptomatic cam and/or pincer morphology, and eleven pain-free controls performed the cross-body lunge during a single session. Trunk, pelvis, hip, knee and ankle kinematics, as well as hip, knee and ankle kinetics and vertical ground reaction forces were examined.

FINDINGS

Overall, the groups performed the movement similarly, with most variables statistically similar between groups. However, pelvis sagittal plane excursion throughout the entire cross-body lunge was significantly larger in those with cam and/or pincer morphology and symptoms compared to those with asymptomatic cam and/or pincer morphology (P = .046, effect size = 0.98).

INTERPRETATION

The results of this study show that cross-body lunge performance is similar across individuals with and without painful cam and/or pincer morphology. However, future research should aim to better understand pelvis biomechanics during sporting activities, as pelvis sagittal plane excursion may have important implications in rehabilitation and sport performance.

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.

Despite patient-reported outcomes improve, patients with femoroacetabular impingement syndrome do not increase their objectively measured sport and physical activity level 1 year after hip arthroscopic surgery. Results from the HAFAI cohort

PURPOSE

Patients with femoroacetabular impingement syndrome (FAIS) are young and middle-aged persons living physically active lives including sports activities. However, measurements of the physical activity level before and after hip arthroscopic surgery in patients with FAIS using both self-reported and objective accelerometer-based measures are lacking. Furthermore, comparing patients with a reference group of persons reporting no hip problems and conducting subgroup analyses investigating changes in physical activity level and self-reported outcomes according to pre-surgery activity level may further highlight the activity pattern for patients.

METHODS

Sixty patients with FAIS eligible for hip arthroscopic surgery were consecutively included in a prospective cohort study (HAFAI cohort) together with 30 reference persons reporting no hip problems. Participants completed the Copenhagen Hip and Groin Outcome Score (HAGOS) together with questions regarding their sports activities. Furthermore, participants wore a three-axial accelerometer for five consecutive days during waking hours. The accelerometer-based data were analysed and presented as total activity and type, frequency and duration of activities.

RESULTS

Patients experienced significant and clinically relevant changes in all HAGOS scores. 88% of patients participated in some kind of sports activity 1 year after surgery. Overall, objectively measured physical activity did not change from before to 1 year after surgery. However, subgroup analyses of the most sedentary patients preoperatively revealed significant changes towards a more active pattern. Compared to reference persons, patients performed less bicycling and running.

CONCLUSION

Despite clinically relevant changes in self-reported outcomes, patients did not increase their overall physical activity level 1 year after surgery. Physical activity levels were lower in patients than in the reference group and patients continued bicycling and running less compared with the reference group.

LEVEL OF EVIDENCE

II.

Hip Kinematics During Single-Leg Tasks in People With and Without Hip-Related Groin Pain and the Association Among Kinematics, Hip Muscle Strength, and Bony Morphology

OBJECTIVE

To compare 3-D hip kinematics during the single-leg squat and step-down in patients with hip-related groin pain to those in asymptomatic participants, and to assess relationships among hip kinematics, muscle strength, and bony morphology.

DESIGN

Controlled laboratory cross-sectional study.

METHODS

Forty patients with hip-related groin pain and 40 matched, asymptomatic participants between 18 and 40 years of age participated. A handheld dynamometer was used to assess hip abductor and external rotator strength. An 8-camera motion-analysis system was used to quantify 3-D kinematics during the single-leg squat and step-down. Magnetic resonance imaging was used to quantify bony morphology. The independent t test and Mann-Whitney U test were used to assess between-group differences. Pearson coefficient correlations were used to assess relationships.

RESULTS

Patients with hip-related groin pain had smaller peak hip flexion angles, smaller knee flexion angles, and lesser squat depth compared to asymptomatic participants during the single-leg squat. Among patients with hip-related groin pain, smaller hip flexion angles during the single-leg squat were associated with hip abductor weakness (r = 0.47, P≤.01). Among asymptomatic participants, smaller peak hip flexion angles during the single-leg squat were associated with less acetabular coverage (r = 0.33, P = .04) and shallow squat depth (r = 0.48, P≤.01); a smaller hip internal rotation angle during the step-down was associated with larger femoral neck shaft angle (r = -0.43, P<.01).

CONCLUSION

Compared to asymptomatic participants, patients with hip-related groin pain had smaller hip and knee flexion angles and shallower squat depth during the single-leg squat. Smaller hip flexion angles were associated with hip abductor weakness among those with hip-related groin pain. J Orthop Sports Phys Ther 2020;50(5):243-251. Epub 6 Jan 2020. doi:10.2519/jospt.2020.9150.

Hip muscle atrophy in patients with acetabular labral joint pathology

Intra-articular hip joint pathology is a source of hip and groin pain in active individuals and is thought to be a precursor to hip osteoarthritis. Limited evidence exists to guide appropriate physiotherapy management for these patients. Identification of which hip muscles are affected may help clinicians to develop effective exercise programs. A cross-sectional observational study in a hospital setting was conducted to investigate the size of individual hip abductor, hip extensor, and hip external rotator muscles in patients with acetabular labral joint pathology compared with age and sex matched healthy subjects. Twelve participants (eight females, four males), aged 20-53 years, with a medical diagnosis of unilateral acetabular labral tear and 12 healthy participants were recruited. Magnetic resonance imaging was used to assess cross-sectional areas of the gluteus minimus, gluteus medius, upper gluteus maximus, lower gluteus maximus, piriformis, and quadratus femoris muscles bilaterally. Gluteus medius muscle cross-sectional area was significantly different between groups (P < 0.01, effect size = 0.92) with muscle size found to be smaller in the pathology group. No differences were found for the other hip muscles (P > 0.05). These findings suggest that hip muscles are not all affected equally by the presence of intra-articular hip joint pathology. Atrophy of specific hip muscles, which are important in hip joint and pelvic stability, may alter hip joint function during gait and functional tasks. Clinicians treating patients with intra-articular hip joint pathology may need to prescribe exercises targeting the specific muscles with demonstrated dysfunction. Clin. Anat. 33:538-544, 2020. © 2019 Wiley Periodicals, Inc.

Femoroacetabular impingement in young adults: assessment and management

Femoroacetabular impingement is a cause of hip pain in young adults as a result of premature dynamic contact between the femur and acetabulum that occurs within the physiological range of hip motion. Diagnosis is made by patient history, clinical examination and radiographic findings. Cross-sectional imaging with computed tomography and magnetic resonance arthrography may be necessary in selected patients. Femoroacetabular impingement can be treated non-operatively with physiotherapist-led conservative care including analgesia and intra-articular steroid injections. Arthroscopic hip surgery aiming to restore pain-free functional range of movement and repair damaged labrum can help in selected patients with no pre-existing osteoarthritis. This review outlines the clinical assessment, investigations and management of femoroacetabular impingement in young adults.