Incidence of acute injuries in Swedish gymnastics with a special focus on cruciate ligament injuries.

BACKGROUND: Gymnastics is a sport with unique technical and physical demands. Elements of high rotational landing impacts may lead to severe injuries. In order to understand the risks of the sport and design injury prevention programs the magnitude of acute injuries must be understood. The aim was to investigate acute injuries, medical invalidity and injury costs in gymnastics using national insurance data. METHODS: Insurance data covering acute injuries in Swedish gymnastics from October 2015 to October 2020 were analyzed. All Swedish gymnasts with either a training or competition license were included (N.=333,932 licenses, 249,823 females; 84,109 males). RESULTS: A total of 1733 acute injuries were reported, and the injury incidence was 5.2 per 1000 gymnast years, with no differences between upper and lower body. The arm followed by the foot and the knee were body locations with highest injury incidence. Skeletal injuries were most common in the arm and foot, and ligament injuries in the foot and knee. The proportion of cruciate ligament injuries was 37% of all knee injuries and 5% of all acute injuries. No significant difference between male and female gymnasts was observed. The highest proportion of medical invalidity was found in the knee (33%), the foot (22%), and the arm (20%). Sixteen percent of all cruciate ligament injuries led to medical invalidity and was the injury causing highest costs to the insurance company. CONCLUSIONS: The knee was the third most common injury location and the injury causing the highest medical invalidity.

Side-to-side differences in knee laxity and side hop test may predispose an anterior cruciate ligament reinjury in competitive adolescent alpine skiers.

An anterior cruciate ligament (ACL) injury is a common, severe injury in alpine skiing, and anterior cruciate ligament reconstruction (ACLR) is frequently performed in competitive alpine skiers younger than 20 years old. To reduce the reinjury rate, both intrinsic and extrinsic risk factors should be examined. The aim of this study was to investigate possible intrinsic risk factors for an ACL reinjury in competitive alpine skiers. A cohort of 384 alpine skiers (191 males/193 females) from the Swedish ski high schools were prospectively followed during their high school years. The students were clinically examined and physically tested prior to each ski season. In addition, the RAND 36-Item health survey 1.0 (SF-36, Copyright 1994 Medical Outcome Trust, distributed by RAND Corporation) and injuries were prospectively registered. Thirty-one of the skiers (five males/26 females) had undergone an ACLR before entering the ski high school. This cohort was analyzed with respect to the occurrence of, and possible risk factors for an ACL reinjury (including ipsilateral and contralateral ACL injuries). Skiers who sustained an ACL reinjury were called the "ACL reinjury group," and those who did not sustain an ACL reinjury were called the "ACL injury group." Notably, 12 of the 31 students (39%), ten female and two male skiers, aged 16.5 (SD 0.5) years, sustained an ACL reinjury during the two first years at the ski high school. In addition, 10 of the 12 ACL reinjuries occurred within 10-23 months from the first injury [m 14.8 (SD4.7)] and two ACL reinjuries occurred at 29 and 47 months, respectively, from the first injury. It is noted that eight of the ACL reinjuries were to the ipsilateral knee and four to the contralateral knee. There were no differences between the groups with respect to muscle flexibility in the lower extremity, Beighton score, and one leg hop for distance or square hop test. Side-to-side differences were found with respect to knee joint laxity, >3 mm, measured with KT-1000 arthrometer (p = 0.02), and the side hop test (p = 0.04). RAND 36-Item health survey did not predict an ACL reinjury. In conclusion, a side-to-side difference in the side hop test and knee joint laxity (KT-1000) may predispose an ACL reinjury in competitive adolescent alpine skiers.

A screening instrument for side dominance in competitive adolescent alpine skiers.

Previous research has shown that high school ski students injure their left anterior cruciate ligament (ACL) more often than their right ACL, and that a prevention program focusing on equal load to the right and left ski turns prevents ACL injuries. Whether the injuries were in the dominant or non-dominant side of ski students was not determined but may be important knowledge to ski coaches for future design of ski-specific training programs. There is no gold standard on how to investigate the dominant side of alpine skiers. Therefore, the aim of this study was to develop a screening instrument consisting of five questions for identifying side dominance and to evaluate side dominance in competitive adolescent alpine skiers. First, 121 competitive adolescent alpine skiers answered the questions on side dominance using a test-retest design. The questions were: which hand/arm (left/right) or foot/leg (left/right) one uses as the first choice when writing, throwing, kicking a ball, jumping over a fence and stair-climbing. A question about safer/better ski turn to the left or to the right was also added. Second, 274 skiers answered the questions at one occasion. A very good agreement was shown in writing and throwing and kicking a ball, and a fair agreement was shown in jumping over a fence and stair climbing. A total of 243 skiers reported right-sided dominance, and seven skiers reported left-sided dominance. One hundred and nineteen of the 121 skiers who took part in the test-retest design answered the question safer/better ski turn, and of those 70 (59%) reported that they had a safer/better ski turn to one side than to the other side. However, the side was not consistent between the two test occasions, and the question did not correlate with side dominance. A combination of the three questions "What hand/arm do you use as first choice when writing?" "What hand/arm do you use as first choice when throwing?" and "What foot/leg do you use as first choice when kicking a ball?", may be used to decide side dominance in adolescent alpine skiers. Most adolescent alpine skiers reported right-sided dominance.

Gymnasts' experiences and perception of a cruciate ligament injury.

BACKGROUND: Gymnastics is a high injury risk sport including difficult technique. A cruciate ligament injury is common, though there are no evidence-based guidelines for return to gymnastics. The gymnasts' experiences may add specificity to a guideline. Therefore, the aim of the present study was to describe the gymnasts' experiences and perception of a cruciate ligament injury. METHODS: An embedded mixed methods design. Semi-structured interviews in 14 gymnasts between March and August 2018. The gymnasts represented a variation in age, sex, discipline, level of gymnastics, re- ruptures, associated injuries and return to gymnastics. The Knee Injury and Osteoarthritis Outcome Score, compared with age matched cruciate ligament injured gymnasts in the Swedish National Knee Ligament Registry, and the Tegner's Activity Score were supplements to the interviews. The interviews covered injury occasion, rehabilitation, return to gymnastics and current experience of the knee joint and were analyzed using qualitative content analysis with an inductive approach. RESULTS: The Knee Injury and Osteoarthritis Outcome Score was consistent with the Swedish National Knee Ligament Registry and showed low levels in the subscales Quality of Life and sports/recreation. One third reported Tegner's Score <6 supporting low levels in Sports/Recreation. The text analysis resulted in two parts "This really happened, cold facts" and "Prerequisites and hindrances for return to gymnastics." The gymnasts' narratives were similar and reached saturation. CONCLUSIONS: A cruciate ligament injury is a large trauma, and the physical and psychological demands must be understood. The results of the present study may be included in a framework for return to gymnastics, where the individual prerequisites and goals should be determined. The timeline within this framework would depend on the extent of the injury, expected time for healing and physical as well as psychological demands with respect to gymnastics' level. It may also include suggestions for different psychological strategies and performance enhancement techniques to increase the gymnasts' self-efficacy and encourage and motivate the gymnasts through the long and demanding rehabilitation.

Risk Factors for Anterior Cruciate Ligament Injury in Competitive Adolescent Alpine Skiers.

BACKGROUND: There is a high risk for anterior cruciate ligament (ACL) injuries in alpine skiers. To reduce or try to prevent these injuries, intrinsic and extrinsic risk factors need to be identified. PURPOSE: To identify possible intrinsic and extrinsic ACL injury risk factors among competitive adolescent alpine skiers. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Between 2006 and 2009, a cohort of 339 alpine ski students (176 male, 163 female) from Swedish ski high schools were prospectively observed in terms of ACL injuries. First-time ACL injuries were recorded. In September, prior to each ski season, the skiers were clinically examined according to a specific knee protocol. RESULTS: Overall, 11 male and 14 female skiers sustained a total of 25 first-episode ACL injuries. The majority of injuries occurred in the left knee (P < .05). Skiers who had participated in alpine skiing for >13 years (hazard ratio, 0.83; 95% CI, 0.68-1.00; P < .05) had a reduced risk of sustaining an ACL injury. Eighteen ACL injuries occurred during training, 12 in the technical discipline of giant slalom, and 8 in slalom. Fourteen skiers reported not to be fatigued at all at the time of injury, and 8 skiers reported that they were somewhat fatigued. CONCLUSION: ACL injuries occurred more often in the left knee than the right. This should be taken into consideration in the design of ACL injury prevention programs. Those who reported a higher number of active years in alpine skiing showed a reduced risk of sustaining an ACL injury. No other factor among those studied could be identified as an independent risk factor for ACL injury.