A retrospective analysis on the correlation between hip pain, physical examination findings, and alpha angle on MR images

Intra-articular Hip Injuries in National Basketball Association Players: A Descriptive Epidemiological Study

Background:

Since the most recent epidemiologic study of injuries in National Basketball Association (NBA) players was completed in 2012, the understanding and diagnosis of intra-articular hip injury has advanced.

Purpose:

To report the epidemiology of intra- versus extra-articular hip injuries in NBA players with regard to missed games, risk factors for injury, and treatment types.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

The NBA injury database was queried for all reported hip and groin injuries from 2013 to 2017. The injuries were then divided into intra-articular and extra-articular types. Variables compared between injury types included player age, NBA tenure, season schedule (preseason or offseason), onset type, injury mechanism, roster position, games missed, time to return to play, and need for surgery.

Results:

A total of 224 athletes sustaining 353 total hip pathologies were identified. Of these injuries, 216 (61.2%) were sustained during game competition and affected 156 (69.6%) of the athletes. Intra-articular injuries represented 39 (11.0%) cases and involved 36 (16.1%) players. The time to return to play was significantly longer after intra-articular versus extra-articular injury (44.6 ± 96.0 vs 11.8 ± 32.0 days; P = .03), and the number of games missed was significantly greater after intra-articular versus extra-articular injury (8.0 ± 18.7 vs 1.54 ± 4.9 games; P = .03). Patients with intra-articular hip injuries were more likely to undergo surgery (odds ratio, 5.5 [95% CI, 1.8-16.7]; P = .005). There was no statistically significant difference in the number of games missed due to surgery (35.2 ± 8.3 [intra-articular] vs 35.4 ± 11.6 [extra-articular]; P = .42) or nonoperative treatment (4.2 ± 3.4 [intra-articular] vs 1.3 ± 0.5 [extra-articular]; P = .11). Years of NBA tenure were not significantly different between intra-articular and extra-articular injuries (7.1 ± 3.7 vs 6.3 ± 4.0 years). For both types of hip injury, there was no correlation between player age and either days to return to play or number of games missed (R² = 0.014).

Conclusion:

NBA players with intra-articular hip injuries underwent surgery more frequently and had a longer return-to-play time compared with those with extra-articular hip injuries. NBA tenure and player age were not correlated with the risk of developing hip injury or the need for surgery.

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

Purpose

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

Methods

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

Results

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

Conclusions

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

Level of Evidence

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

Increased range of motion but otherwise similar clinical outcome of arthroscopy over open osteoplasty for femoroacetabular impingement at midterm follow-up: A systematic review

BACKGROUND

A systematic review was conducted comparing patient reported outcomes measures (PROMs), functional scores, and the rate of complications between arthroscopic and open treatment for femoroacetabular impingement (FAI) at mid-term follow-up.

MATERIAL AND METHODS

This systematic review was performed according to the PRISMA guidelines. The literature search was performed in October 2020. All clinical trials treating FAI using open osteoplasty or arthroscopic surgery were considered for inclusion. Only articles reporting >12 months follow-up were included.

RESULTS

Data from 97 articles (9981 procedures) were collected. At a mean 19.2 months follow-up there was no difference between the two cohorts. At a mean follow-up of 38 months, the external rotation was increased in the arthroscopic group (P < 0.0001). The modified Harris Hip Score scored greater in favour of the open osteoplasty group (P = 0.04), as did the Hip Outcome Score - Activities of Daily Living subscale (P = 0.01). At a mean 45.1 months the arthroscopic group presented greater external rotation (P < 0.0001) and SF-12 Mental (P = 0.04). The modified Harris Hip Score was greater in favour of the open osteoplasty group (P = 0.03), as was the HOS-ADL (P = 0.01). Regarding complications, the arthroscopic group experienced lower rates of subsequent revisions (P < 0.0001).

CONCLUSION

Based on the significant reduction of revisions-rate and significant increase in range of motion, arthroscopy treatment for the management of FAI may be recommended.

The Association of α Angle on Disease Severity in Adolescent Femoroacetabular Impingement

BACKGROUND

Femoroacetabular Impingement (FAI) is a common cause of hip pain in adolescent patients. Clinical exam and radiographic markers, such as α angle and lateral center edge angle (LCEA), are commonly used to aid in the diagnosis of this condition. The purpose of this study was to correlate preoperative α angle and LCEA with preoperative symptoms, intraoperative findings, and preoperative and postoperative patient reported outcomes (PROs) in the adolescent patient.

METHODS

A retrospective analysis of prospectively collected data was conducted for all patients who underwent operative intervention for FAI at an academic institution over an 11-year period. Preoperative imaging was obtained and measured for LCEA and α angle. PROs (modified Harris Hip Score, Hip Disability and Osteoarthritis Outcome Score, and UCLA score) were collected preoperatively, as well as 1, 2, and 5 years postoperatively. Operative intervention was either open surgical hip dislocation or arthroscopic, and intraoperative disease was graded using the Beck Classification system. Patients with minimum 1-year follow-up were included in statistical analysis.

RESULTS

There were 86 hips (64 female hips) included with an average age of 16.3 years (range, 10.4 to 20.5 y), with an average of 37 months of follow-up. There was no correlation between severity of preoperative symptoms or difference between pre and postoperative PROs for both α angle and LCEA. Overall, significant improvement was noted in modified Harris Hip Score, Hip Disability and Osteoarthritis Outcome Score, and UCLA Score (P<0.001 for each). Independent of preoperative symptoms, increased α angle correlated with more severe intraoperative labral disease (P<0.001), and longer length of labral tear (Corr 0.295, P<0.01). Femoral head and acetabular articular cartilage damage did not correlate with α angle or LCEA, nor did overall severity of disease.

CONCLUSIONS

In adolescent patients with FAI, increased α angle was found to significantly correlate with labral pathology, including increased length of tear and severity of disease, irrespective of preoperative symptoms or postoperative patient reported outcomes.

LEVEL OF EVIDENCE

Level III-retrospective.

Hip pain and its correlation with cam morphology in young skiers-a minimum of 5 years follow-up

BACKGROUND

There is conflicting evidence regarding the association between cam morphological changes and hip pain, and it remains unclear who with cam morphology will develop hip pain and who will not. This study aimed to investigate the correlation between cam morphology, hip pain, and activity level at a 5-year follow-up in young Alpine and Mogul skiers.

METHOD

All students (n = 76) at Åre Ski National Sports High School were invited and accepted participation in this prospective study at baseline. Magnetic resonance imaging (MRI) of both hips was conducted to evaluate the presence of cam morphology (α-angle ≥ 55°) and its size alongside the reporting of hip pain, type, and frequency of training by the Back and hip questionnaire, at baseline. After 5 years, the skiers were invited to complete a shortened version of the same questionnaire.

RESULTS

A total of 60 skiers (80%) completed the follow-up questionnaire, of which 53 had concomitant MRI data. Cam morphology was present in 25 skiers (47.2%, 39 hips). Hip pain at baseline and at follow-up was reported in 17 (28.3%) and 22 (36.7%) skiers, respectively. No correlations were found between the activity level, the frequency, and the size of cam morphology and hip pain, except for the right hip α-angle at 1 o'clock and hip pain in skiers with cam morphology at baseline (rs = 0.49; P = 0.03) and at follow-up (rs = 0.47; P = 0.04). A total of 73.3% skiers had retired, of which 48% reported this was due to injuries.

CONCLUSION

Hip pain was not shown to be correlated, or had a low correlation, with activity level and the presence and size of cam morphology in young skiers on a 5-year follow-up. Based on these results, cam morphology or activity level did not affect hip pain to develop during 5 years of follow-up in young skiers. Furthermore, this study highlights that almost 75% of young elite skiers had retired from their elite career with almost 50% reporting that this was due to injuries sustained from skiing.

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.

The relationship between cam morphology and hip and groin symptoms and signs in young male football players

Background

Conflicting and limited high‐quality prospective data are available on the associations between cam morphology and hip and groin symptoms and range of motion (ROM).

Objectives

This cross‐sectional cohort study investigated associations between cam morphology presence, size and duration and symptoms and ROM.

Methods

Academy male football players (n = 49, 17‐24 years) were included. Standardized antero‐posterior pelvic and frog‐leg lateral radiographs were obtained at baseline, 2.5‐ and 5‐year follow‐up. The femoral head‐neck junction was quantified by:

Visual score. Cam morphology (flattening or prominence), large cam (prominence).

Alpha angle. Cam morphology (≥60°), large cam (≥78°).

Cam morphology duration was defined as long (first present at baseline) or short (only from 2.5‐ to 5‐year follow‐up). Current symptoms at 5‐year follow‐up were assessed using a hip and groin pain question and by the “Hip and Groin Outcome Score” (HAGOS). HAGOS scores were categorized into: most symptoms (≥2 domains in lowest interquartile range [IQR]), least symptoms (≥2 domains in highest IQR). Hip ROM was measured by goniometry at 5‐year follow‐up.

Results

Large cam morphology based on visual score was associated with hip and groin pain (23.8% vs. 7.1%, OR: 3.17, CI: [1.15‐8.70], P = .026), but not with HAGOS scores. Cam morphology presence, size, and duration were associated with limited flexion of around 6° and/or 3° to 6° for internal rotation.

Conclusion

Cam morphology presence, size, and duration were associated with limited hip flexion and/or internal rotation, but differences might not exceed the minimal clinical important difference. Whether cam morphology results in symptoms is uncertain.

Assessment of Hip Translation In Vivo in Patients With Femoracetabular Impingement Syndrome Using 3-Dimensional Computed Tomography

Purpose

To determine the 3-dimensional (3D) in vivo hip translation in patients with symptomatic femoroacetabular impingement syndrome (FAIS) using 3D computed tomography (CT) models with the hip in neutral and FABER (flexion, abduction, and the external rotation) positions and to identify patient predictors associated with the degree of hip translation.

Methods

Seventy-eight patients with FAIS and cam lesions underwent CT scans in neutral and FABER positions. Demographics including age, sex, and body mass index (BMI) were recorded for each patient. The cam deformity was characterized both in plain x-ray film and 3D. Translation between both positions was calculated using a validated high-precision 3D-3D registration technique. Univariate and multivariate regression analyses sought factors correlated with translation.

Results

The mean age of the patients included in the analysis was 36.3 ± 9.2 years, with 51% of the study group being female. The mean 3D femoral head center translation was 0.84 ± 0.37 mm, decomposed into vectors on standard anatomical directions as 0.13 ± 0.58 mm medial, 0.10 ± 0.54 mm posterior, and 0.08 ± 0.46 mm inferior. Multivariate analysis demonstrated that total translation was associated with larger alpha angles (β = 0.014; 95% confidence interval [CI] 0.003-0.024; P = .013), and greater BMI (β = 0.033; 95% CI 0.001-0.065; P = .042). Furthermore, posterior–inferior translation was associated with BMI (β = 0.032; 95% CI 0.003-0.061; P = .031), whereas medial–lateral translation is associated with the female sex (β = 0.388; 95% CI 0.124-0.634; P = .002), and smaller head radius (β = –0.068; 95% CI –0.128 to –0.007; P = .029).

Conclusions

As a provocative maneuver, FABER positioning in patients with FAIS resulted in an average measurable translation of the femoral head center in the posterior, medial, and inferior direction. Factors including sex, BMI, and alpha angle predicted the degree of translation.

Clinical Relevance

The current study demonstrates that there is measurable hip translation between the neutral and FABER positions in patients with symptomatic FAIS, which may cause hip microinstability. Furthermore, the study found an association between hip translation and both modifiable and nonmodifiable factors. This may indicate the need for more comprehensive preoperative surgical planning, intraoperative dynamic examination of the hip, and consideration of capsular plication in certain patients.