Spine & Sports Institute

Abstract

Background Standardized assessment of sports injuries provides important epidemiological information and also directions for injury prevention.

Purpose To analyze the frequency, characteristics, and causes of injuries incurred during the Summer Olympic Games 2008.

Study Design Descriptive epidemiology study.

Methods The chief physicians and/or chief medical officers of the national teams were asked to report daily all injuries newly incurred during the Olympic Games on a standardized injury report form. In addition, injuries were reported daily by the physicians at the medical stations at the different Olympic venues and at the polyclinic in the Olympic Village.

Results Physicians and/or therapists of 92 national teams covering 88% of the 10 977 registered athletes took part in the study. In total, 1055 injuries were reported, resulting in an incidence of 96.1 injuries per 1000 registered athletes. Half of the injuries (49.6%) were expected to prevent the athlete from participating in competition or training. The most prevalent diagnoses were ankle sprains and thigh strains. The majority (72.5%) of injuries were incurred in competition. One third of the injuries were caused by contact with another athlete, followed by overuse (22%) and noncontact incidences (20%). Injuries were reported from all sports, but their incidence and characteristics varied substantially. In relation to the number of registered athletes, the risk of incurring an injury was highest in soccer, taekwondo, hockey, handball, weightlifting, and boxing (all ≥15% of the athletes) and lowest for sailing, canoeing/kayaking, rowing, synchronized swimming, diving, fencing, and swimming.

Conclusion The data indicate that the injury surveillance system covered almost all of the participating athletes, and the results highlight areas of high risk for sport injury such as the in-competition period, the ankle and thigh, and specific sports. The identification of these factors should stimulate future research and subsequent policy change to prevent injury in elite athletes.

Abstract

Background Patellofemoral pain syndrome is one of the most common chronic knee injuries; however, little research has been done to determine the risk factors for this injury.

Hypothesis Altered lower extremity kinematics and kinetics, decreased strength, and altered postural measurements will be risk factors.

Study Design Cohort study (prognosis); Level of evidence, 2.

Methods A total of 1597 participants were enrolled in this investigation and prospectively followed from the date of their enrollment (July 2005, July 2006, or July 2007) through January 2008, a maximum of 2.5 years of follow-up. Each participant underwent baseline data collection during their pre-freshman summer at the United States Naval Academy. Baseline data collection included 3-dimensional motion analysis during a jump-landing task, 6 lower extremity isometric strength tests, and postural alignment measurements (navicular drop and Q angle).

Results Risk factors for the development of patellofemoral pain syndrome included decreased knee flexion angle, decreased vertical ground-reaction force, and increased hip internal rotation angle during the jump-landing task. Additionally, decreased quadriceps and hamstring strength, increased hip external rotator strength, and increased navicular drop were risk factors for the development of patellofemoral pain syndrome.

Conclusion Multiple modifiable risk factors for patellofemoral pain syndrome pain have been identified in this investigation. To decrease the incidence of this chronic injury, the risk factors for patellofemoral pain syndrome need to be targeted in injury prevention programs.

Clinical Relevance Prevention programs should focus on increasing strength of the lower extremity musculature along with instructing proper mechanics during dynamic movements to decrease the incidence of patellofemoral pain syndrome.

Abstract

Background Meniscal and anterior cruciate ligament (ACL) injuries are common in college football athletes. The effect of meniscectomy and/or ACL surgery on the length of an athlete’s career in the National Football League (NFL) has not been well examined.

Hypothesis Athletes with a history of meniscectomy or ACL surgery before the NFL combine have a shorter career than matched controls.

Study Design Case-control study; Level of evidence, 3.

Methods A database containing the injury history and career NFL statistics of athletes from 1987–2000 was used to match athletes with a history of meniscectomy and/or ACL surgery, and no other surgery or major injury, to controls without previous surgeries. Athletes were matched by position, year drafted, round drafted, and additional injury history.

Results Fifty-four athletes with a history of meniscectomy, 29 with a history of ACL reconstruction, and 11 with a history of both were identified and matched with controls. Isolated meniscectomy reduced the length of career in years (5.6 vs 7.0; P = .03) and games played (62 vs 85; P = .02). Isolated ACL surgery did not significantly reduce the length of career in years or games played. Comparing the athletes with meniscectomy or ACL reconstruction to athletes with combined ACL reconstruction and meniscectomy, a history of both surgeries, resulted in a shorter career in games started (7.9 vs 35.1; P <.01), games played (41 vs 63; P = .07), and years (4.0 vs 5.8; P = .08) than a history of either surgery alone.

Conclusion A history of meniscectomy, but not ACL reconstruction, shortens the expected career of a professional football player. A combination of ACL reconstruction and meniscectomy may be more detrimental to an athlete’s durability than either surgery alone. Further research is warranted to better understand how these injuries and surgeries affect an athlete’s career and what can be done to improve the long-term outcome after treatment.

Abstract

Background Anterior cruciate ligament injuries are common in athletes and have serious sequelae. A valid clinical tool that reliably identifies individuals at an increased risk for ACL injury would be highly useful for screening sports teams, because individuals identified as “high-risk” could then be provided with intensive prevention programs.

Hypothesis A clinical screening tool (the Landing Error Scoring System, or LESS) will reliably identify subjects with potentially high-risk biomechanics.

Study Design Cohort study (Diagnosis); Level of evidence, 2.

Methods A jump-landing-rebound task was used. Off-the-shelf camcorders recorded frontal and sagittal plane views of the subject performing the task. The LESS was scored from replay of this video. Three-dimensional lower extremity kinematics and kinetics were also collected and used as the gold standard against which the validity of the LESS was assessed. Three trials of the jump-landing task were collected for 2691 subjects. Kinematic and kinetic measures were compared across LESS score quartiles using 1-way analysis of variance; LESS quartiles were compared across genders using the chi-square test. The LESS scores from a subset of 50 subjects were rescored to determine intrarater and interrater reliability.

Results Subjects with high LESS scores (poor jump-landing technique) displayed significantly different lower extremity kinematics and kinetics compared with subjects with low LESS scores (excellent jump-landing technique). Women had higher (worse) LESS scores than men. Intrarater and interrater reliability of the LESS ranged from good to excellent.

Conclusion The LESS is a valid and reliable tool for identifying potentially high-risk movement patterns during a jump-landing task

Abstract

Background A high percentage of female athletes who sustain an anterior cruciate ligament (ACL) rupture suffer serious long-term consequences such as osteoarthritis and disability. Thus, identification of risk factors has high clinical relevance in the prevention of ACL rupture.

Hypothesis Noninjured athletes with low knee flexor electromyography (EMG) preactivity and high knee extensor EMG preactivity during sidecutting are at increased risk of future ACL rupture.

Study Design Cohort study (prognosis); Level of evidence, 2.

Methods Fifty-five elite female athletes (team handball and soccer) aged 24 ± 5 years with no history of ACL injury were tested for EMG preactivity of vastus lateralis and medialis, rectus femoris, semitendinosus, and biceps femoris during a standardized side-cutting maneuver. The incidence of ACL ruptures was registered in the following 2 match seasons.

Results During the subsequent 2 match seasons, 5 athletes sustained a confirmed noncontact ACL rupture. Before injury, all 5 players displayed a neuromuscular pattern that differed from the noninjured players, characterized by reduced EMG preactivity for the semitendinosus (ST) and elevated EMG preactivity for the vastus lateralis (VL) (P < .01). On the basis of these findings, a high-risk zone was defined as one standard deviation above the mean VL-ST difference. In our population, 5 of 10 subjects with a VL-ST difference in this zone sustained an ACL injury during the study period.

Conclusion In the present study, currently noninjured female athletes with reduced EMG preactivity of the ST and increased EMG preactivity of the VL during side cutting were at increased risk of future noncontact ACL rupture. Our data indicate that a high-risk zone can be used to identify noninjured players at high risk of future ACL rupture. Consequently, individual preventive efforts can be introduced in time. However, large prospective studies are needed to confirm this finding before definitive clinical recommendations can be mad

Background Anterior cruciate ligament injuries are common in athletes and have serious sequelae. A valid clinical tool that reliably identifies individuals at an increased risk for ACL injury would be highly useful for screening sports teams, because individuals identified as “high-risk” could then be provided with intensive prevention programs.

Hypothesis A clinical screening tool (the Landing Error Scoring System, or LESS) will reliably identify subjects with potentially high-risk biomechanics.

Study Design Cohort study (Diagnosis); Level of evidence, 2.

Methods A jump-landing-rebound task was used. Off-the-shelf camcorders recorded frontal and sagittal plane views of the subject performing the task. The LESS was scored from replay of this video. Three-dimensional lower extremity kinematics and kinetics were also collected and used as the gold standard against which the validity of the LESS was assessed. Three trials of the jump-landing task were collected for 2691 subjects. Kinematic and kinetic measures were compared across LESS score quartiles using 1-way analysis of variance; LESS quartiles were compared across genders using the chi-square test. The LESS scores from a subset of 50 subjects were rescored to determine intrarater and interrater reliability.

Results Subjects with high LESS scores (poor jump-landing technique) displayed significantly different lower extremity kinematics and kinetics compared with subjects with low LESS scores (excellent jump-landing technique). Women had higher (worse) LESS scores than men. Intrarater and interrater reliability of the LESS ranged from good to excellent.

Conclusion The LESS is a valid and reliable tool for identifying potentially high-risk movement patterns during a jump-landing task.

1. Darin A. Padua, PhD, ATC, †‡*,
2. Stephen W. Marshall, PhD†§,
3. Michelle C. Boling, PhD, ATC||,
4. Charles A. Thigpen, PhD, ATC||,
5. William E. Garrett, Jr, MD, PhD¶ and
6. Anthony I. Beutler, MD#

Background Latissimus dorsi and teres major tendon tears are uncommon injuries. Only a few case reports exist, mainly in high-level athletes.

Purpose To describe a series of latissimus dorsi and teres major tendon tears in professional baseball pitchers.

Study Design Case series; Level of evidence, 4.

Methods Injury data from 3 Major League Baseball clubs were collected over a total of 10 seasons. Any baseball player who sustained an injury to either the latissimus dorsi or teres major identified on magnetic resonance imaging (MRI) was included. All injured players were treated nonoperatively with a goal of returning to full velocity throwing at 3 months from the time of injury.

Results Ten players sustained injuries to the latissimus dorsi and/or the teres major during pitching. The MRI findings documented 5 isolated latissimus dorsi tears, 4 isolated teres major tears, and 1 combined injury. All athletes returned to pitching, and all but 1 player returned to baseball at the same level of competition in the same season. Nine of 10 players returned at 3 months from the time of their injury. One recurrence was seen 6 months after returning to throwing; however, this healed with further nonoperative treatment, and the player returned to competition at the same level 6 weeks later. One player had continued shoulder symptoms and retired at the end of the season.

Conclusion Although uncommon, tears of the latissimus dorsi and teres major occur in professional baseball players. Acute injuries are demonstrated on standard shoulder MRI, although larger field-of-view images are required to accurately assess the injury. Most heal successfully with nonoperative treatment, and most players are able to return to the same level of competition in 3 months.

Scott G. Kaar, MD, St Louis University, Department of Orthopaedic Surgery, 3635 Vista at Grand Blvd, St Louis, MO 63110