Hip Internal Rotation Is Correlated to Radiographic Findings of Cam Femoroacetabular Impingement in Collegiate Football Players

doi:10.1016/j.arthro.2012.04.153

Arthroscopy: The Journal of Arthroscopic & Related Surgery

Volume 28, Issue 11, November 2012, Pages 1661-1670

https://doi.org/10.1016/j.arthro.2012.04.153 Get rights and content

Purpose

The objective of this study was to determine whether physical examinations (flexion–abduction–external rotation [FABER], impingement, range-of-motion profiles) could be used to detect the bony abnormalities of femoroacetabular impingement (FAI) in an athletic population.

Methods

We performed a prospective study of 65 male collegiate football players. Both hips were evaluated by 2 orthopaedic surgeons for radiographic signs of FAI. The alpha angle and head-neck offset were measured on frog-leg lateral films. The center-edge angle, acetabular index, crossover sign, and alpha angle were measured on anteroposterior films. Measurements were averaged for both observers. Maximum hip range of motion in flexion (supine) and internal/external rotation (supine, sitting, and prone) was measured with a goniometer. Pain provoked by the impingement and FABER tests was also recorded. Examinations were completed at 2 of 4 stations (2 duplicates), each staffed by 2 clinicians (1 examined and 1 measured). The relation between each range-of-motion and radiographic measure was determined. Data from each station were assessed separately. Only those regressions significant (P < .05) for paired stations were considered clinically significant.

Results

The alpha angle and head-neck offset measured on the frog-leg lateral films were significantly correlated (all P < .01) to supine, sitting, and prone internal rotation for all stations. Correlation coefficients ranged from −0.59 to −0.35 for alpha angle and 0.42 to 0.57 for head-neck offset. Although 95% of the hips had at least 1 radiographic sign of FAI, pain was reported in only 8.5% and 2.3% during the impingement and FABER tests, respectively.

Conclusions

Internal rotation correlates to radiographic measures of cam FAI in this cohort of collegiate football players. Football players with diminished internal rotation in whom hip pain develops should be evaluated for underlying cam FAI abnormalities.

Level of Evidence

Level IV, therapeutic case series.

Section snippets

Subject Selection

The University of Utah football team was invited to participate in this prospective, institutional review board–approved study (IRB 40479). Of 96 players, 67 provided informed consent and participated. As previously reported, each subject's hip condition was assessed with a questionnaire based on the validated Hip Outcome Score.15, 16

Physical Examination

Physical examinations were completed on a single day during the routine pre-participation athletic evaluation. Examinations were performed at 4 stations. Stations

Subject Characteristics

Of the 67 football players who underwent radiographic evaluation in our previous study,¹¹ 2 were excluded because they did not complete the physical examinations. The remaining 65 football players were aged 21 ± 1.9 years with a mean height of 185 ± 6.4 cm and weight of 102 ± 19 kg. Overall, most of the players noted that their hips had no further symptoms at the time of this study, as self-reported on the questionnaire.¹¹ The mean (± standard deviation) activities–of–daily living and sports

Discussion

Prior knowledge of an increased risk for FAI may improve treatment outcomes by decreasing the time between the onset of symptoms and appropriate diagnosis, during which further chondrolabral damage may occur. The objective of this study was to determine whether physical examinations could be used to detect radiographic changes consistent with FAI in an athletic population, specifically collegiate football players. Internal rotation measured in supine, sitting, and prone positions negatively

Conclusions

Acknowledgment

The authors acknowledge Jill Erickson, Alexej Barg, Jesse Chrastil, and Clint Barnett for assistance with physical examination data collection.

References (31)

T.L. Johnston et al.
Relationship between offset angle alpha and hip chondral injury in femoroacetabular impingement
Arthroscopy
(2008)
R.L. Martin et al.
Evidence of validity for the hip outcome score
Arthroscopy
(2006)
R.L. Martin et al.
Evidence of reliability and responsiveness for the hip outcome score
Arthroscopy
(2008)
B.A. Braly et al.
Clinical examination of the athletic hip
Clin Sports Med
(2006)
H.D. Martin et al.
The pattern and technique in the clinical evaluation of the adult hip: The common physical examination tests of hip specialists
Arthroscopy
(2010)
N.J. Giori et al.
Acetabular retroversion is associated with osteoarthritis of the hip
Clin Orthop Relat Res
(2003)
M. Tanzer et al.
Osseous abnormalities and early osteoarthritis: The role of hip impingement
Clin Orthop Relat Res
(2004)
M. Beck et al.
Hip morphology influences the pattern of damage to the acetabular cartilage: Femoroacetabular impingement as a cause of early osteoarthritis of the hip
J Bone Joint Surg Br
(2005)
J.W. Byrd et al.
Arthroscopic management of femoroacetabular impingement in athletes
Am J Sports Med
(2011)
M. Philippon et al.
Femoroacetabular impingement in 45 professional athletes: Associated pathologies and return to sport following arthroscopic decompression
Knee Surg Sports Traumatol Arthrosc
(2007)

C.M. Larson et al.

Does arthroscopic FAI correction improve function with radiographic arthritis?

Clin Orthop Relat Res

(2011)

M. Tannast et al.

Femoroacetabular impingement: Radiographic diagnosis—What the radiologist should know

AJR Am J Roentgenol

(2007)

K. Hack et al.

Prevalence of cam-type femoroacetabular impingement morphology in asymptomatic volunteers

J Bone Joint Surg Am

(2010)

K.K. Gosvig et al.

Prevalence of malformations of the hip joint and their relationship to sex, groin pain, and risk of osteoarthritis: A population-based survey

J Bone Joint Surg Am

(2010)

J. Abellàn et al.

Radiological evidence of femoroacetabular impingement in asymptomatic athletes

Br J Sports Med

(2011)

Cited by (53)

Acetabular labrum and cartilage contact mechanics during pivoting and walking tasks in individuals with cam femoroacetabular impingement syndrome
2023, Journal of Biomechanics
Citation Excerpt :
However, these findings identified differences in either tensile strains and/or shear stresses, which cannot be accounted for when using STO modeling. Patients with cam FAIS often have reduced internal rotation ROM of the hip (Clohisy et al., 2009; Griffin et al., 2016; Kapron et al., 2012). A cadaver study investigating the torsional loading and ROM in cam FAIS hips before and after cam resection surgery reported reduced contact and torque required to achieve the same ROM for internal rotation after cam resection surgery, but no reduction for external rotation (Ng et al., 2019).
Femoroacetabular impingement syndrome (FAIS) is a motion-related pathology of the hip characterized by pain, morphological abnormalities of the proximal femur, and an elevated risk of joint deterioration and hip osteoarthritis. Activities that require deep flexion are understood to induce impingement in cam FAIS patients, however, less demanding activities such as walking and pivoting may induce pain as well as alterations in kinematics and joint stability. Still, the paucity of quantitative descriptions of cam FAIS has hindered understanding underlying hip joint mechanics during such activities. Previous in silico studies have employed generalized model geometry or kinematics to simulate impingement between the femur and acetabulum, which may not accurately capture the interplay between morphology and motion. In this study, we utilized models with participant-specific bone and articular soft tissue anatomy and kinematics measured by dual-fluoroscopy to compare hip contact mechanics of cam FAIS patients to controls during four activities of daily living (internal/external pivoting and level/incline walking). Averaged across the gait cycle during incline walking, patients displayed increased strain in the anterior joint (labrum strain: p-value = 0.038, patients: 11.7 ± 6.7 %, controls: 5.0 ± 3.6 %; cartilage strain: p-value = 0.029, patients: 9.1 ± 3.3 %, controls: 4.2 ± 2.3). Patients also exhibited increased average anterior cartilage strains during external pivoting (p-value = 0.039; patients: 13.0 ± 9.2 %, controls: 3.9 ± 3.2 %]). No significant differences between patient and control contact area and strain were found for level walking and internal pivoting. Our study provides new insights into the biomechanics of cam FAIS, including spatiotemporal hip joint contact mechanics during activities of daily living.
Patients With Generalized Joint Hypermobility Have Thinner Superior Hip Capsules and Greater Hip Internal Rotation on Physical Examination
2022, Arthroscopy, Sports Medicine, and Rehabilitation
Citation Excerpt :
When we controlled for female sex and age, these differences remained significant, suggesting that both BTS and female sex have some correlation with bony morphology (including acetabular and femoral version as well as alpha angle). Our findings are in line with previous studies, which have identified that smaller alpha angles and greater femoral anteversion are correlated with more IR at the hip.22,23 When examining hip ROM, we found significant differences between patients who have GJH and those who do not have GJH in addition to differences between sexes.
To compare preoperative hip range of motion (ROM), hip capsular thickness on magnetic resonance imaging (MRI), and bony morphology on radiographs and computed tomography (CT) between patients with and without joint hypermobility as measured by the Beighton Test score (BTS), with subanalysis based on sex and age.
Consecutive patients who underwent hip arthroscopy for a diagnosis of femoroacetabular impingement syndrome with or without dysplasia were retrospectively reviewed. Patient BTS, hip ROM, demographics, surgical data, morphologic measures on radiographs and CT, and MRI findings including hip capsule thickness at various locations were compiled. Multiple statistical tests were performed, including multivariable linear or logistic regression models, while controlling for BTS, age, and sex.
In total, 99 patients were included with a mean age of 29 ± 9.9 years; 62 (62.6%), were female. Forty patients (40.4%) had a BTS ≥4. Female patients (P < .001) and younger patients (26.7 vs 30.9 years, P = .030) were more likely to have a BTS ≥4. Male patients had significantly thicker superior capsules (3.4 mm vs. 2.8 mm, P = .034). BTS was not associated with capsular thickness when controlling for sex. On CT, femoral version (18.9° vs 11.4°, P < .001), and McKibben index (37.8° vs. 28.2°, P < .001) were significantly greater in those with a BTS ≥4. Patients with a BTS ≥4 had more hip internal rotation at 90° of flexion (15.0° vs 10.0°, P < .001), when prone (30.0° vs 20.0°, P = .004), and in extension (10.0° vs. 5.0°, P < .001).
All female patients, regardless of Beighton score, and all patients with a BTS ≥4 indicated for primary hip arthroscopy for femoroacetabular impingement syndrome with or without dysplasia were more likely to have thinner superior hip capsules on MRI and greater hip internal rotation on exam. Bony morphologic differences exist between sexes and between patients with and without hypermobility, likely contributing to differences in ROM.
III, retrospective cohort study.
Hip Range of Motion Is Increased After Hip Arthroscopy for Femoroacetabular Impingement: A Systematic Review
2022, Arthroscopy, Sports Medicine, and Rehabilitation
To investigate the impact of arthroscopic correction of symptomatic femoroacetabular impingement on postoperative hip range of motion (ROM), as an objectively measured postoperative clinically reported outcome.
A systematic review of the current literature was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, OVID/MEDLINE, EMBASE, and Cochrane databases were queried in November 2020. Studies not reporting pre- to postoperative ROM measurements were excluded. Methodologic quality was assessed using the MINORS assessment, and certainty of evidence was assessed using the GRADE approach. Effect size using standardized mean differences assessed magnitude of change between pre- and postoperative ROM.
In total, 23 studies were included evaluating 2,332 patients. Mean age ranged from 18 to 44.2 years. Flexion, internal rotation (IR), and external rotation (ER) were the predominantly measured ROMs reported in 91%, 100% and 65% of studies, respectively. Observed change following hip arthroscopy was considered significant in 57.1% (flexion), 74% (IR), and 20% (ER). Effect size of change in significantly improved ROMs were weak (16.7% flexion, 33.3% ER), moderate (58.3% flexion, 29.4% IR), and large (25% flexion, 64.7% IR, 66.7% ER). For goniometric assessment mean observed changes ranged as follows: flexion: 0.1° to 12.2°; IR: 3.6° to 21.9°; ER: –2.6° to 12.8°. For computed tomography–simulated assessment, the mean observed change ranged as follows: flexion: 3.0° to 8.0°; IR 9.3° to 14.0°.
Outcome studies demonstrate overall increased range of flexion and IR post-hip arthroscopy, with a moderate and large effect respectively. Change in ER is less impacted following hip arthroscopy. Certainty of evidence to support this observation is low. Current research evaluating changes in this functional ability is limited by a lack of prospective studies and non-standardized measurement evaluation techniques.
Level IV, systematic review of Level II-IV studies.
The Bipolar Hip: How Acetabular and Femoral Pathomorphology Affects Hip Motion in Femoral Acetabular Impingement Syndrome
2020, Arthroscopy - Journal of Arthroscopic and Related Surgery
Citation Excerpt :
Previous studies using dynamic, in vivo biplanar fluoroscopy would suggest that active hip ROM is terminated by pain and soft-tissue impingement rather than direct osseous collision.25 However, we have also previously shown that hip internal rotation correlates with plain radiographic osseous morphology.9 Similarly, other authors have shown that osseous morphology correlates with hip motion in both intra- and extra-articular impingement.26
To investigate the individual and combined contributions of acetabular and femoral morphology to hip range of motion (ROM) in patients with femoroacetabular impingement syndrome (FAIS) by use of computed tomography measurements and hip ROM evaluated on physical examination.
A retrospective chart and radiographic analysis of patients presenting with hip pain suggestive of FAIS was performed. The femoral neck-shaft angle, femoral version, magnitude and clock-face location of the alpha angle, midcoronal center-edge angle (CEA), midsagittal CEA, acetabular version, and McKibbin index were measured on computed tomography scans. Univariate and multivariate linear regression analyses determined which measurements correlated with hip ROM, including hip flexion as well as hip internal and external rotation with the hip in 90° of flexion.
Two hundred hips that met the inclusion and exclusion criteria during the eligibility period were included in the analysis. The mean age was 31.9 ±10.0 years, there were 145 female patients (72%), and the mean body mass index was 25.2 ± 5.0. Multivariate linear regression analysis showed that the midsagittal CEA was the only measurement correlating with flexion (q = .031) whereas the femoral neck-shaft angle and McKibbin index were the only significant variables that correlated with external rotation (q = .031 and q < .001, respectively). Finally, the McKibbin index and maximum alpha angle were the only variables that correlated with internal rotation (q < .001 and q = .034, respectively).
Multivariate analysis showed that combined acetabular and femoral version significantly correlated with internal and external rotation whereas femoral version in isolation did not. Increased cam morphology remained a significant contributor to reduced internal rotation but did not affect hip flexion. These data suggest that hip ROM is affected by both femoral pathomorphology and acetabular pathomorphology and that careful evaluation of both should be conducted prior to corrective osteoplasty or osteotomy.
Level IV, retrospective case series.
Hip Injuries in the Contact Athlete
2019, Operative Techniques in Sports Medicine
Citation Excerpt :
Meanwhile, posterior labral tears commonly result in the reproduction of pain with passive flexion and internal rotation with a posteriorly directed load.32-34 Recent data have demonstrated considerable overlap between labral pathology and the presence of underlying bony impingement secondary to FAI in athletes.28,35-38 FAI consists of abnormal bony morphology at the femoral neck (cam lesion), acetabular rim (pincer lesion), or mixed (combined lesion), resulting in abnormal, repetitive abutment of the anterolateral femoral head-neck junction against the anterolateral acetabular rim.38
Despite being relatively uncommon when compared to injuries to the ankle and knee, hip injuries in the contact athlete account for 5%-6% of all athletic-related injuries with increasing prevalence over the last decade. Athletic hip injuries represent a spectrum of often overlapping intra- and extra-articular disorders with the potential to cause significant disability and time lost from sport. Advancements in imaging modalities, arthroscopic instrumentation, and surgical techniques have improved diagnostic capabilities and treatment outcomes of athletic hip injuries. Furthermore, increased screening and better recognition of the role of femoroacetabular impingement on the development of intra-articular hip pathology and instability has provided physicians with a treatable risk factor deterring further hip disorders. This chapter provides physicians with a brief overview of commonly encounter hip injuries in the contact athlete, namely: muscle strains, contusion, labral injuries, and hip instability secondary to dislocation or subluxation in the setting of femoroacetabular impingement, as well as the previously described “sports hip triad.”
The Italian Consensus Conference on FAI Syndrome in Athletes (Cotignola Agreement)
2023, Muscles, Ligaments and Tendons Journal

View all citing articles on Scopus

: The authors report that they have no conflicts of interest in the authorship and publication of this article.

View full text

Original ArticleHip Internal Rotation Is Correlated to Radiographic Findings of Cam Femoroacetabular Impingement in Collegiate Football Players

Purpose

Methods

Results

Conclusions

Level of Evidence

Section snippets

Subject Selection

Physical Examination

Subject Characteristics

Discussion

Conclusions

Acknowledgment

Arthroscopy

Arthroscopy

Arthroscopy

Clin Sports Med

Arthroscopy

Acetabular retroversion is associated with osteoarthritis of the hip

Clin Orthop Relat Res

Osseous abnormalities and early osteoarthritis: The role of hip impingement

Clin Orthop Relat Res

Hip morphology influences the pattern of damage to the acetabular cartilage: Femoroacetabular impingement as a cause of early osteoarthritis of the hip

J Bone Joint Surg Br

Arthroscopic management of femoroacetabular impingement in athletes

Am J Sports Med

Femoroacetabular impingement in 45 professional athletes: Associated pathologies and return to sport following arthroscopic decompression

Knee Surg Sports Traumatol Arthrosc

Does arthroscopic FAI correction improve function with radiographic arthritis?

Clin Orthop Relat Res

Femoroacetabular impingement: Radiographic diagnosis—What the radiologist should know

AJR Am J Roentgenol

Prevalence of cam-type femoroacetabular impingement morphology in asymptomatic volunteers

J Bone Joint Surg Am

Prevalence of malformations of the hip joint and their relationship to sex, groin pain, and risk of osteoarthritis: A population-based survey

J Bone Joint Surg Am

Radiological evidence of femoroacetabular impingement in asymptomatic athletes

Br J Sports Med

Original Article
Hip Internal Rotation Is Correlated to Radiographic Findings of Cam Femoroacetabular Impingement in Collegiate Football Players