Young elite Alpine and Mogul skiers have a higher prevalence of cam morphology than non-athletes

Unravelling the hip-spine dilemma from the CHECK-cohort: is sagittal pelvic morphology linked to radiographic signs of femoroacetabular impingement?

INTRODUCTION

To date the aetiology of femoroacetabular impingement (FAI) is still not completely understood. There are mechanical theories that suggest symptomatic FAI is linked to sagittal pelvic morphology and spinopelvic-femoral dynamics. The aim of this study is to evaluate the relation of sagittal pelvic morphology and orientation to radiographic signs of FAI. Additionally, we test whether the relation between FAI and spinopelvic parameters differs in osteoarthritic hips.

METHODS

From a prospective, observational cohort study, 1002 patients between 45 and 65 years old with a first episode of knee or hip pain were followed for 8 years. All patients who had lateral lumbar radiographs and clinical and radiographic follow-up of the hips were included in the present study. Range of internal rotation of the hip as well as radiographic signs of FAI (alpha and Wiberg angle) and presence of hip osteoarthritis (Kellgren and Lawrence) were systematically measured at baseline. Pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS)) were measured at 8-year follow-up. Associations between PI, PT, SS and FAI parameters were tested using generalised estimating equations.

RESULTS

421 subjects, 842 hips, were included. No significant relations between PI, PT or SS and alpha or Wiberg angle were found. Comparison of hips with and without radiological sign(s) of FAI showed no differences in PI, PT or SS. There was no relation between range of internal rotation of the hip and spinopelvic parameters.

CONCLUSION

Sagittal pelvic morphology and orientation are not related to the presence of radiological signs of FAI in this study population.

Arthroscopy Confers Favorable Clinical Outcomes in Asian Patients with Borderline Developmental Dysplasia of the Hip

OBJECTIVE

Hip arthroscopy has recently appeared as a successful therapy in treating borderline developmental dysplasia of the hip (BDDH). This study aimed to describe the minimal 2-year follow-up after hip arthroscopy for patients with BDDH in the Asian population and use the combination of lateral center edge angle (LCEA) and alpha angles to detect the appearance of impingement in the BDDH population.

METHODS

This retrospective investigation was conducted utilizing information from arthroscopically treated BDDH patients in 2018 and 2019. The following patient-reported outcomes were reported: modified Harris Hip Score, Hip Outcome Score-Activities of Daily Living, International Hip Outcome Tool 12-component form, and Visual Analog Scale. We also considered the clinical data regarding radiological measurements, intraoperative findings, interventions, complications, and subsequent surgical revisions, in the analysis of combination angles in detecting the occurrence of impingement. Patients with asymptomatic contralateral hips from traumatic hip injury (pelvic fracture) served as the control group. A 2:1 propensity score matching was based on age, sex, and BMI. A receiver operating characteristic curve (ROC) was used to identify the thresholds of combination angles and their accuracies.

RESULTS

A total of 77 hips met the inclusion and exclusion requirements. After the follow-up period, most patients showed a considerable improvement in patient-reported outcomes compared to their preoperative values (P < 0.001 for all). The overall rate of complications was 5.2%, whereas the rate of revisions was 3.9%. Increasing preoperative alpha angle age was significantly positively correlated with improving patient-reported outcomes. The combined angle cut-off was determined to be 80.5° (AUC, 0.858; 95% CI: 0.757-0.938; sensitivity (SE), 98.1%; specificity (SP), 74.1%; P < 0.001) for the occurrence of impingement in BDDH population.

CONCLUSION

Good patient-reported outcomes and low revision rates can be expected in the BDDH population with careful selection of patients in Asian populations. A combination angle >80.5° could be a reliable predictive factor of impingement in BDDH populations.

Risk of total hip arthroplasty after elite sport: linking 3304 former world-class athletes with the Norwegian Arthroplasty Register

OBJECTIVES

At present, there is no cure for osteoarthritis (OA), but severe hip joint degeneration can require total hip arthroplasty (THA). The literature on OA after elite sport is limited. We hypothesise that elite athletic activity increases the risk of receiving a THA later in life.

METHODS

We linked a cohort of former Norwegian world-class athletes (1402 females and 1902 males, active 1936-2006) to the Norwegian Arthroplasty Register (THA performed 1987-2020). We used standardised incidence ratio (SIR), one-minus Kaplan-Meier and relative Cox regression (relative HR, RHR), with 95% CIs, and funnel plots at age 75, to assess THA risk for different sport disciplines, joint impact categories of sport disciplines and sex. The risk of THA for the corresponding general Norwegian population was used as reference.

RESULTS

We found an overall increased risk for THA for the former elite athletes (SIR 2.11, 95% CI 1.82 to 2.40) at age 75 years, compared with the general population. THA risk at age 75 years was 11.6% for female athletes and 8.3% for male athletes. SIR was 1.90 (95% CI 1.49 to 2.31) for female and 2.28 (95% CI 1.87 to 2.70) for male athletes. Among males, high joint impact sport disciplines were associated with increased risk compared with low-impact sport disciplines (RHR 1.81, 95% CI 1.06 to 3.08, p=0.029).

CONCLUSION

Having been an elite athlete was associated with a doubling of THA risk compared with the general population for both sexes. High joint impact sport disciplines were associated with subsequent THA for male athletes.

Femoroacetabular Impingement in Elite Skiers and Snowboarders: Return to Sports and Outcomes After Hip Arthroscopy

BACKGROUND

Hip arthroscopy has been shown to be an effective treatment for femoroacetabular impingement (FAI) in high-level athletes; however, limited outcome and return-to-play data exist for hip arthroscopy in skiers and snowboarders.

PURPOSES

To determine the return-to-sports rate of elite skiers and snowboarders who have undergone hip arthroscopic surgery for FAI and to assess hip-related outcomes at a minimum 2-year follow-up.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Elite skiers and snowboarders who underwent hip arthroscopy for the treatment of FAI between 2005 and 2018 were identified via a retrospective review of prospectively collected data. Data were obtained from fis-ski.org, usskiandsnowboard.org, xgames.com, and wikipedia.org, including information on each player's career length, participation on a national team, and time between surgery and first competition after surgery. Patient-reported outcomes (PROs) were prospectively collected preoperatively and at minimum 2 years postoperatively.

RESULTS

In total, 26 elite skiers and snowboarders (34 hips) were included. The mean ± standard deviation age at surgery was 24.5 ± 6.7 years (range, 18.7-46.8 years). A total of 85% (22/26) returned to elite-level competition at 8.9 months (range, 2.9-23.7 months) with an average career length of 3.6 ± 2.7 years after surgery. Four athletes (5 hips) required revision arthroscopy, with adhesions being the most frequent indication. At a mean follow-up of 7.7 ± 3.2 years, significant improvement in PROs (P < .05) was demonstrated for the Hip Outcome Score (HOS)-Activities of Daily Living (from 76 ± 20 to 95 ± 6), HOS-Sport Specific Subscale (from 63 ± 28 to 92 ± 14), modified Harris Hip Score (from 70 ± 19 to 89 ± 12), and 12-Item Short Form Health Survey Physical Component Summary (from 45 ± 11 to 54 ± 8). Patient satisfaction had a mean of 8 ± 2 (range, 1-10) and median of 10.

CONCLUSION

The return-to-competition rate in elite skiers and snowboarders after hip arthroscopy for FAI was 85% at an average of 8.9 months and with a career length of 3.6 years after surgery. Significant improvement in PROs was demonstrated for the HOS-Activities of Daily Living, HOS-Sport Specific Subscale, modified Harris Hip Score, and 12-Item Short Form Health Survey Physical Component Summary, with a median patient satisfaction score of 10. These findings support hip arthroscopy as an effective procedure for the treatment of FAI in elite skiers and snowboarders with symptomatic activity-limiting hip pain, allowing them to return to their previous levels of competition at a high rate.

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

BACKGROUND

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

PURPOSE

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

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

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

RESULTS

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

CONCLUSION

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

REGISTRATION

CRD4202018001 (PROSPERO).

Hip Arthroscopy for Femoroacetabular Impingement-Associated Labral Tears: Current Status and Future Prospects

Femoroacetabular impingement (FAI) has emerged as a common cause of hip pain, especially in young patients. While the exact cause of FAI is unknown, it is thought to result from repetitive microtrauma to the proximal femoral epiphysis leading to abnormal biomechanics. Patients typically present with groin pain that is exacerbated by hip flexion and internal rotation. Diagnosis of FAI is made through careful consideration of patient presentation as well as physical exam and diagnostic imaging. Use of radiographs can help diagnose both cam and pincer lesions, while the use of MRI can diagnose labral tears and cartilage damage associated with FAI. Both non-operative and surgical options have their role in the treatment of FAI and its associated labral tears; however, hip arthroscopy has had successful outcomes when compared with physical therapy alone. Unfortunately, chondral lesions associated with FAI have had poorer outcomes with a higher conversion rate to arthroplasty. Capsular closure following hip arthroscopy has shown superior clinical outcomes and therefore should be performed if possible. More recently, primary labral reconstruction has emerged in the literature as a good option for irreparable labral tears. While non-operative management may have its role in treating patients with FAI, hip arthroscopy has developed a successful track record in being able to treat cam and pincer lesions, chondral damage, and labral injuries.

Characterizing femoroacetabular impingement in professional Nordic Skiers

OBJECTIVE

Studies have shown a high prevalence of femoroacetabular impingement (FAI) among elite athletes yet there is a paucity of data on FAI in Nordic skiers. The purpose of this study was to determine the prevalence of radiographic FAI in professional Nordic Combined Skiers and Ski jumpers compared to controls and assess functional outcomes including hip range of motion (ROM) and pain in patients with radiographic evidence of FAI compared to those without it.

METHODS

A cohort of elite Nordic Skiers underwent medical history, physical examination, and pelvic radiographs at their visit with a fellowship-trained sports medicine physician. On pelvis radiographs, Alpha angle>55 degrees was deemed cam-positive, and positive crossover signs, Tönnis<0, or LCEA>40 were deemed pincer positive. Further stratification was performed by sex, ski event type, hip pain, presence of cam lesions, and presence of pincer lesions. Spearman correlation matrix was performed to measure the association between radiographic measurements and ROM.

RESULTS

Nineteen Nordic skiers and nineteen age, sex, and BMI matched controls were included in the study. There were no significant differences in age, sex, BMI, and hip pain between groups. While Nordic skiers demonstrated decreased ROM bilaterally on external rotation compared to controls, skiers had larger ROM bilaterally on extension, abduction, adduction compared to controls. Skiers were significantly more likely to have bilateral crossover sign and alpha angles>55 compared to controls. Subgroup analysis showed that Cam positive patients had higher flexion and adduction ROM and pincer positive patients had significantly higher flexion and abduction ROM compared to patients without cam and pincer lesions respectively. Patients with hip pain had significantly lower right hip abduction ROM compared to patients without hip pain. No significant correlations were seen between radiographic measurements and ROM.

CONCLUSION

Similar to other elite 'hip heavy' sport athletes, Nordic skiers gave a notably higher prevalence of radiographic cam and pincer type morphology and significantly higher ROM compared to nonathletic controls. Clinicians evaluating Nordic skiers should be aware of these baseline findings with respect to a possible elevated long-term risk of symptomatic FAI in these athletes as well as other conditions related to radiographic FAI.

Imaging Review of Alpine Ski Injuries

Skiing is a continuously evolving winter sport, responsible for a considerable number of musculoskeletal injuries. Specific injury patterns and mechanisms in the upper and lower extremities, head, and spine are influenced by skier expertise and skill, position during injury, and environmental conditions. Predilection for certain joints and injury patterns have changed over time, largely due to technological advancements in equipment, increased awareness campaigns, and preventive protocols. Knowledge and understanding of these trends and developments can aid the radiologist to reach a timely and accurate diagnosis, thereby guiding clinical management and potentially reducing the overall incidence of debilitation and death.

Injury risks among elite competitive alpine skiers are underestimated if not registered prospectively, over the entire season and regardless of whether requiring medical attention

PURPOSE

Prospective studies assessing the injuries occurring in elite competitive alpine skiers are lacking, and a full picture of all injuries, including those not requiring medical attention, is absent. Likewise, little is known about the sex-specific injury risks and patterns of elite skiers throughout an entire season (i.e. an off-season preparation period and a competition period). Accordingly, this study investigated the injuries of a national team cohort with respect to season period and sex.

METHODS

Over an entire season, all injuries occurring in 44 Swiss National Ski Team members (25 females and 19 males) were registered, regardless of whether they required medical attention. Skiers were prospectively monitored by the Oslo Sports Trauma Research Centre (OSTRC) questionnaire and by continuously updated team medical records. Finally, these data were used as a reference for supplemental interviews, in which the correctness and completeness of the prospective data were verified.

RESULTS

The risk of suffering at least one injury during an entire season was 75.0% with a 95% confidence interval (73.1%, 76.9%) for traumatic injuries, and 52.3% (50.0%, 54.5%) for overuse injuries. Traumatic injuries concerned the head, lower leg and knee, while overuse injuries affected the lumbar spine, knee and hip. During the competition period, skiers were more prone to traumatic injuries, while during the off-season preparation period, skiers' risk was higher for overuse injuries. Over an entire season, there were no sex differences. However, females were more vulnerable to traumatic injuries during the preparation period and overuse injuries during the competition period, while males had a higher risk for overuse injuries during the preparation period.

CONCLUSIONS

When prospectively registering injuries among elite competitive alpine skiers over an entire season, regardless of whether the injuries required medical attention, the injury risks were alarmingly high and substantially larger than those previously reported. Moreover, since injury risks and patterns are season period and sex dependent, it is strongly recommended that (1) injury registration focuses on both the off-season preparation period and the competition period and (2) prevention efforts are specifically tailored to the sex of the athletes.

LEVEL OF EVIDENCE

II.

Bone and body characteristics of freestyle and nonfreestyle skiers

BACKGROUND

Freestyle skiers must optimize their aerial performance by maintaining the strength and coordination to propel themselves in the air and adapt to landings and take-offs on uneven surfaces. The purpose of this study is to investigate the differences in areal bone mineral density (aBMD) and body composition in freestyle skiers and nonfreestyle skiing controls.

HYPOTHESIS

We hypothesized that the unique demands and summation of forces experienced by freestyle athletes would manifest as greater femoral neck aBMD, lower percent body fat, and lower BMI than nonfreestyle skiing controls.

LEVEL OF EVIDENCE

Level 3, Retrospective Cohort Study.

METHODS

18 freestyle skiers (14M 4F, [27.56 ± 5.22 years]) and 15 controls (7M 8F, [26.93 ± 3.54 years]) were measured with dual energy X-ray absorptiometry (DXA) to determine total body composition, hip and lumbar spine aBMD, and bone mineral composition (BMC). Height and weight were measured with an in-office stadiometer and scale. Questionnaires were used to determine physical activity and pertinent medical history. Between-group variations were analyzed with an analysis of variance (ANOVA) and stratified by sex.

RESULTS

Percent body fat, hip and lumbar spine aBMD, BMC, and area were all similar between freeski and nonfreeski athletes (p<0.05 for all). BMI was significantly lower in male freeski athletes (23.97kg/m2, 95% CI [22.75-25.18]) compared to nonfreestyle skiing controls (26.64kg/m2, 95% CI [24.43-28.86]) (p=0.03).

CONCLUSIONS

Freestyle skiers have a lower BMI than nonfreestyle skiers. All skiers in this study has similar percent body fat, aBMD, and BMC. This pilot study supports that there are unique musculoskeletal adaptations based on type of skiing.

CLINICAL RELEVANCE

Skiers endure a variety of intense physical forces yet remain understudied despite high orthopedic injury rates. This study serves to broaden the current sports health literature and explore the physical demands and subsequent physiology of freestyle skiers.

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.