Grethe Myklebust

Injury Mechanisms for Anterior Cruciate Ligament Injuries in Team Handball A Systematic Video Analysis

Objective To describe the mechanisms for anterior cruciate ligament injuries in female team handball. Study Design Descriptive video analysis. Methods Twenty videotapes of anterior cruciate ligament injuries from Norwegian or international competition were collected from 12 seasons (1988-2000). Three medical doctors and 3 national team coaches systematically analyzed these videos to describe the injury mechanisms and playing situations. In addition, 32 anterior cruciate ligament-injured players in the 3 upper divisions in Norwegian team handball were interviewed during the 1998-1999 season to compare the injury characteristics between player recall and the video analysis. Results Two main injury mechanisms for anterior cruciate ligament injuries in team handball were identified. The most common (12 of 20 injuries), a plant-and-cut movement, occurred in every case with a forceful valgus and external or internal rotation with the knee close to full extension. The other main injury mechanism (4 of 20 injuries), a 1-legged jump shot landing, occurred with a forceful valgus and external rotation with the knee close to full extension. The results from the video analysis and questionnaire data were similar. Conclusions The injury mechanism for anterior cruciate ligament injuries in female team handball appeared to be a forceful valgus collapse with the knee close to full extension combined with external or internal rotation of the tibia.

Prevention of anterior cruciate ligament injuries in female team handball players: a prospective intervention study over three seasons.

ObjectiveTo assess the effect of a neuromuscular training program on the incidence of anterior cruciate ligament injuries in female team handball players. DesignProspective intervention study. SettingFemale team handball: Division I–III in Norway. ParticipantsPlayers from the three top divisions: control season (1998–1999), 60 teams (942 players); first intervention season (1999–2000), 58 teams (855 players); second intervention season (2000–2001), 52 teams (850 players). InterventionA five-phase program (duration, 15 min) with three different balance exercises focusing on neuromuscular control and planting/landing skills was developed and introduced to the players in the autumn of 1999 and revised before the start of the season in 2000. The teams were instructed in the program and supplied with an instructional video, poster, six balance mats, and six wobble boards. Additionally, a physical therapist was attached to each team to follow up with the intervention program during the second intervention period. Main Outcome MeasuresThe number of anterior cruciate ligament injuries during the three seasons and compliance with the program. ResultsThere were 29 anterior cruciate ligament injuries during the control season, 23 injuries during the first intervention season (OR, 0.87; CI, 0.50–1.52; p = 0.62), and 17 injuries during the second intervention season (OR, 0.64; CI, 0.35–1.18; p = 0.15). In the elite division, there were 13 injuries during the control season, six injuries during the first intervention season (OR, 0.51; CI, 0.19–1.35; p = 0.17), and five injuries in the second intervention season (OR, 0.37; CI, 0.13–1.05; p = 0.06). For the entire cohort, there was no difference in injury rates during the second intervention season between those who complied and those who did not comply (OR, 0.52; CI, 0.15–1.82; p = 0.31). In the elite division, the risk of injury was reduced among those who completed the anterior cruciate ligament injury prevention program (OR, 0.06; CI, 0.01–0.54; p = 0.01) compared with those who did not. ConclusionsThis study shows that it is possible to prevent anterior cruciate ligament injuries with specific neuromuscular training.

Non-contact ACL injuries in female athletes: an International Olympic Committee current concepts statement

The incidence of anterior cruciate ligament (ACL) injury remains high in young athletes. Because female athletes have a much higher incidence of ACL injuries in sports such as basketball and team handball than male athletes, the IOC Medical Commission invited a multidisciplinary group of ACL expert clinicians and scientists to (1) review current evidence including data from the new Scandinavian ACL registries; (2) critically evaluate high-quality studies of injury mechanics; (3) consider the key elements of successful prevention programmes; (4) summarise clinical management including surgery and conservative management; and (5) identify areas for further research. Risk factors for female athletes suffering ACL injury include: (1) being in the preovulatory phase of the menstrual cycle compared with the postovulatory phase; (2) having decreased intercondylar notch width on plain radiography; and (3) developing increased knee abduction moment (a valgus intersegmental torque) during impact on landing. Well-designed injury prevention programmes reduce the risk of ACL for athletes, particularly women. These programmes attempt to alter dynamic loading of the tibiofemoral joint through neuromuscular and proprioceptive training. They emphasise proper landing and cutting techniques. This includes landing softly on the forefoot and rolling back to the rearfoot, engaging knee and hip flexion and, where possible, landing on two feet. Players are trained to avoid excessive dynamic valgus of the knee and to focus on the “knee over toe position” when cutting.

Comprehensive warm-up programme to prevent injuries in young female footballers: cluster randomised controlled trial

Objective To examine the effect of a comprehensive warm-up programme designed to reduce the risk of injuries in female youth football. Design Cluster randomised controlled trial with clubs as the unit of randomisation. Setting 125 football clubs from the south, east, and middle of Norway (65 clusters in the intervention group; 60 in the control group) followed for one league season (eight months). Participants 1892 female players aged 13-17 (1055 players in the intervention group; 837 players in the control group). Intervention A comprehensive warm-up programme to improve strength, awareness, and neuromuscular control during static and dynamic movements. Main outcome measure Injuries to the lower extremity (foot, ankle, lower leg, knee, thigh, groin, and hip). Results During one season, 264 players had relevant injuries: 121 players in the intervention group and 143 in the control group (rate ratio 0.71, 95% confidence interval 0.49 to 1.03). In the intervention group there was a significantly lower risk of injuries overall (0.68, 0.48 to 0.98), overuse injuries (0.47, 0.26 to 0.85), and severe injuries (0.55, 0.36 to 0.83). Conclusion Though the primary outcome of reduction in lower extremity injury did not reach significance, the risk of severe injuries, overuse injuries, and injuries overall was reduced. This indicates that a structured warm-up programme can prevent injuries in young female football players. Trial registration ISRCTN10306290.

Mechanisms for Noncontact Anterior Cruciate Ligament Injuries: Knee Joint Kinematics in 10 Injury Situations From Female Team Handball and Basketball

Background The mechanism for noncontact anterior cruciate ligament injury is still a matter of controversy. Video analysis of injury tapes is the only method available to extract biomechanical information from actual anterior cruciate ligament injury cases. Purpose This article describes 3-dimensional knee joint kinematics in anterior cruciate ligament injury situations using a model-based image-matching technique. Study Design Case series; Level of evidence, 4. Methods Ten anterior cruciate ligament injury video sequences from womens handball and basketball were analyzed using the model-based image-matching method. Results The mean knee flexion angle among the 10 cases was 23° (range, 11°-30°) at initial contact (IC) and had increased by 24° (95% confidence interval [CI], 19°-29°) within the following 40 milliseconds. The mean valgus angle was neutral (range, -2° to 3°) at IC, but had increased by 12° (95% CI, 10°-13°) 40 milliseconds later. The knee was externally rotated 5° (range, -5° to 12°) at IC, but rotated internally by 8° (95% CI, 2°-14°) during the first 40 milliseconds, followed by external rotation of 17° (95% CI, 13°-22°). The mean peak vertical ground-reaction force was 3.2 times body weight (95% CI, 2.7-3.7), and occurred at 40 milliseconds after IC (range, 0-83). Conclusion Based on when the sudden changes in joint angular motion and the peak vertical ground-reaction force occurred, it is likely that the anterior cruciate ligament injury occurred approximately 40 milliseconds after IC. The kinematic patterns were surprisingly consistent among the 10 cases. All players had immediate valgus motion within 40 milliseconds after IC. Moreover, the tibia rotated internally during the first 40 milliseconds and then external rotation was observed, possibly after the anterior cruciate ligament had torn. These results suggest that valgus loading is a contributing factor in the anterior cruciate ligament injury mechanism and that internal tibial rotation is coupled with valgus motion. Prevention programs should focus on acquiring a good cutting and landing technique with knee flexion and without valgus loading of the knee.

Knee Function and Prevalence of Knee Osteoarthritis After Anterior Cruciate Ligament Reconstruction A Prospective Study With 10 to 15 Years of Follow-up

Background Few prospective long-term studies of more than 10 years have reported changes in knee function and radiologic outcomes after anterior cruciate ligament (ACL) reconstruction. Purpose To examine changes in knee function from 6 months to 10 to 15 years after ACL reconstruction and to compare knee function outcomes over time for subjects with isolated ACL injury with those with combined ACL and meniscal injury and/or chondral lesion. Furthermore, the aim was to compare the prevalence of radiographic and symptomatic radiographic knee osteoarthritis between subjects with isolated ACL injuries and those with combined ACL and meniscal and/or chondral lesions 10 to 15 years after ACL reconstruction. Study Design Cohort study; Level of evidence, 2. Methods Follow-up evaluations were performed on 221 subjects at 6 months, 1 year, 2 years, and 10 to 15 years after ACL reconstruction with bone-patellar tendon-bone autograft. Outcome measurements were KT-1000 arthrometer, Lachman and pivot shift tests, Cincinnati knee score, isokinetic muscle strength tests, hop tests, visual analog scale for pain, Tegner activity scale, and the Kellgren and Lawrence classification. Results One hundred eighty-one subjects (82%) were evaluated at the 10- to 15-year follow-up. A significant improvement over time was revealed for all prospective outcomes of knee function. No significant differences in knee function over time were detected between the isolated and combined injury groups. Subjects with combined injury had significantly higher prevalence of radiographic knee osteoarthritis compared with those with isolated injury (80% and 62%, P = .008), but no significant group differences were shown for symptomatic radiographic knee osteoarthritis (46% and 32%, P = .053). Conclusion An overall improvement in knee function outcomes was detected from 6 months to 10 to 15 years after ACL reconstruction for both those with isolated and combined ACL injury, but significantly higher prevalence of radiographic knee osteoarthritis was found for those with combined injuries.

Development and validation of a new method for the registration of overuse injuries in sports injury epidemiology: the Oslo Sports Trauma Research Centre (OSTRC) Overuse Injury Questionnaire

Background Current methods for injury registration in sports injury epidemiology studies may substantially underestimate the true burden of overuse injuries due to a reliance on time-loss injury definitions. Objective To develop and validate a new method for the registration of overuse injuries in sports. Methods A new method, including a new overuse injury questionnaire, was developed and validated in a 13-week prospective study of injuries among 313 athletes from five different sports, cross-country skiing, floorball, handball, road cycling and volleyball. All athletes completed a questionnaire by email each week to register problems in the knee, lower back and shoulder. Standard injury registration methods were also used to record all time-loss injuries that occurred during the study period. Results The new method recorded 419 overuse problems in the knee, lower back and shoulder during the 3-month-study period. Of these, 142 were classified as substantial overuse problems, defined as those leading to moderate or severe reductions in sports performance or participation, or time loss. Each week, an average of 39% of athletes reported having overuse problems and 13% reported having substantial problems. In contrast, standard methods of injury registration registered only 40 overuse injuries located in the same anatomical areas, the majority of which were of minimal or mild severity. Conclusion Standard injury surveillance methods only capture a small percentage of the overuse problems affecting the athletes, largely because few problems led to time loss from training or competition. The new method captured a more complete and nuanced picture of the burden of overuse injuries in this cohort.

Clinical, Functional, and Radiologic Outcome in Team Handball Players 6 to 11 Years after Anterior Cruciate Ligament Injury A Follow-up Study

Background Long-term outcome after anterior cruciate ligament injury among top-level pivoting athletes is unknown. Purpose To evaluate outcome among competitive team handball players after anterior cruciate ligament injury. Study Design Prospective cohort study. Methods A previously studied group of 86 elite players who had an anterior cruciate ligament rupture were invited to participate in follow-up evaluations a mean of 7.8 years later. Results Among the 57 operatively treated patients who returned for follow-up, 33 (58%) returned to team handball at their preinjury level, compared with 18 of 22 (82%) in the nonoperative group. Eleven of the 50 players (22%) who continued playing reinjured their anterior cruciate ligament when playing team handball. The overall Lysholm score was 85 ± 13 in both groups, but the five players classified as poor were all operatively treated. Nearly half of the players had an International Knee Documentation Committee classification of abnormal or severely abnormal. There were significant differences between the injured and uninjured leg in functional (2.5% to 8%), strength (3.8% to 10.1%), and KT-1000 arthrometer tests (27%). In the operatively treated group, 11 developed radiologic gonarthrosis, compared with 6 in the nonoperatively treated group. There was no correlation between radiologic findings and pain scores. Conclusion A more restrictive attitude regarding return to competitive pivoting sports after anterior cruciate ligament injury may be warranted.

Prevention of Injuries Among Male Soccer Players A Prospective, Randomized Intervention Study Targeting Players With Previous Injuries or Reduced Function

Background This study was conducted to investigate whether the most common injuries in soccer could be prevented, and to determine if a simple questionnaire could identify players at increased risk. Hypothesis Introduction of targeted exercise programs to male soccer players with a history of previous injury or reduced function in the ankle, knee, hamstring, or groin will prevent injuries. Study Design Randomized controlled trial; Level of evidence, 2. Methods A total of 508 players representing 31 teams were included in the study. A questionnaire indicating previous injury and/or reduced function as inclusion criteria was used to divide the players into high-risk (HR) (76%) and low-risk (LR) groups. The HR players were randomized individually into an HR intervention group or HR control group. Results A total of 505 injuries were reported, sustained by 56% of the players. The total injury incidence was a mean of 3.2 (95% confidence interval [CI], 2.5–3.9) in the LR control group, 5.3 (95% Cl, 4.6–6.0) in the HR control group (P = .0001 vs the LR control group), and 4.9 (95% Cl, 4.3–5.6) in the HR intervention group (P = .50 vs the HR control group). For the main outcome measure, the sum of injuries to the ankle, knee, hamstring, and groin, there was also a significantly lower injury risk in the LR control group compared with the 2 other groups, but no difference between the HR intervention group and the HR control group. Compliance with the training programs in the HR intervention group was poor, with only 27.5% in the ankle group, 29.2% in the knee group, 21.1% in the hamstring group, and 19.4% in the groin defined as having carried out the minimum recommended training volume. Conclusion The players with a significantly increased risk of injury were able to be identified through the use of a questionnaire, but player compliance with the training programs prescribed was low and any effect of the intervention on injury risk could not be detected.

Effect of Neuromuscular Training on Proprioception, Balance, Muscle Strength, and Lower Limb Function in Female Team Handball Players

ObjectiveIntroduction of a neuromuscular training program will increase muscle strength, balance, and proprioception in elite female handball players. DesignProspective intervention study. ParticipantsThirty-five female team handball players from 2 teams in the elite division participated. Their mean age was 23 (±2.5) years, and their mean weight was 69.2 (±7.3) kg. They had played handball for 14.9 (±3.2) years, 4.7 (±2.8) years at the top level. The total number of training hours per week was 10 to 11. InterventionBased on earlier studies and knowledge about common risk situations in team handball, an anterior cruciate ligament (ACL) injury prevention program with 3 different sets of exercises was developed, each set with a 5-step progression from simple to more challenging exercises. The teams were instructed to use the program a minimum of 3 times a week during a training period of 5 to 7 weeks, and then once a week during the season. The duration of each training session was approximately 15 minutes. Main outcome measuresBalance (KAT 2000), proprioception (threshold to detection of passive motion), muscle strength (Cybex 6000), and 3 functional knee tests. The players were tested pretraining (test 1) and 8 weeks (test 2) and 12 months (test 3) after the training started. ResultsThere was a significant improvement in dynamic balance between test 1 and test 2, with a balance index (BI) of 924 (±225) and 778 (±174), respectively (P = 0.01). The effect on dynamic balance was maintained 1 year after training (BI, 730 ± 156). For static balance, no statistically significant changes were found. For the other variables measured, there were no statistical differences during the study period. ConclusionThe ACL injury prevention training program improved dynamic balance in an elite team handball players.