Anterior Cruciate Ligament Sprains Research Articles

Pediatric Low-Grade ACL Sprains: Trends in Characteristics, Management, and Outcomes

Background:Anterior cruciate ligament (ACL) injuries are among the most common knee injuries in pediatric athletes. While much of the literature focuses on partial or complete tear of the ligament, there is little information on low-grade ACL sprains in either the adult or pediatric literature.Purpose:This study seeks to provide an analysis of grade 1 pediatric ACL sprains investigating injury characteristics, and report trends in management and outcomes.Methods:A retrospective review of patients, aged 8-19 years, presenting to a sports medicine clinic with a knee injury between January 2014-February 2021 was performed. Electronic medical records were queried for a diagnosis of low-grade ACL sprain based on radiology (MRI) reports that identified the injury. Charts were reviewed to collect data on demographics, sport history, injury details, clinical exam, return to play (RTP), and MRI findings. Descriptive statistics and comparisons within gender, age, and RTP were analyzed.Results:67 patients were diagnosed with a grade 1 ACL sprain based upon clinical assessment and MRI findings and treated for such. Average age at injury was 14.51±2.46 years (56.72% male), with a mean RTP of 8.77±6.67 weeks from date of diagnosis and 12.57± 8.04 weeks from date of injury. Most frequent activities when injured were soccer (23.88%), football (16.42%), and basketball (14.93%).0 patients underwent ACL surgical treatment; 2 patients underwent surgery for concomitant injuries (both meniscus tears). 55 patients (82.09%) sustained one or more concomitant injuries: bone contusion (50.91%), non-ACL ligamentous injury (30.91%), meniscus injury (25.45%), soft tissue/muscular injury (12.73%), other (31.48%). 23 patients (37.7%) had non-negative Lachman on clinical exam. Successful conservative interventions included therapy (95.45%), bracing (87.88%), and activity restrictions (86.15%).Females were more likely to be injured in their primary sport than males (82.14% vs. 59.46%, p=0.05). Analysis of bone contusion location vs. RTP clearance date was performed. Patients who took longer to RTP (16+ vs <16 weeks) were more likely to also have a lateral femoral condylar (LFC) contusion (75% vs. 16.67%, p=0.05).Conclusion:Given limited literature on the topic, this review provides presentation characteristics and initial RTP correlates for pediatric low-grade ACL sprains. While longer term follow-up is needed as we continue to learn about the injury, the success rate of conservative treatment indicates that therapy, bracing, and activity restrictions may be considered over surgical management for low-grade ACL sprains.

Ancillary findings in distinguishing between anterior cruciate ligament mucoid degeneration and sprain on MRI: a practical approach.

Imaging findings of both anterior cruciate ligament (ACL) sprain and mucoid degeneration overlap in some cases, which may cause errors in magnetic resonance imaging (MRI) evaluation. To determine the ancillary findings on MRI in distinguishing between ACL sprain and mucoid degeneration, and also to obtain a diagnostic scheme. MRI scans of 77 patients with ACL mucoid degeneration and 77 cases with ACL sprain were retrospectively evaluated to compare with regard to parameters of age, sex, side, the status of posterior cruciate ligament - medial collateral ligament - lateral collateral ligament, bone marrow edema, intraosseous cyst, subchondral sclerosis, chondromalacia, meniscus tear, effusion, and osteochondral body. A decision tree algorithm was created to predict pathology in ACL, whether it was a sprain or mucoid degeneration. The prevalence of female sex, femoral intraosseous cyst, tibial intraosseous cyst, subchondral sclerosis, femoral chondromalacia, tibial chondromalacia, medial meniscus tear, and lateral meniscus tear were significantly higher in the ACL mucoid degeneration group (P < 0.001, P = 0.016, P < 0.001, P = 0.003, P < 0.001, P < 0.001, P < 0.001, and P < 0.001, respectively). The probability of being mucoid degeneration increased 41.2 times (95% confidence interval [CI] = 5.296-321.132) in cases with tibial intraosseous cyst and increased 1.05 times (95% CI = 1.010-1.080) with each one-year increase in age (P < 0.001 and P = 0.011, respectively). The decision tree algorithm had an overall accuracy of 79.2%. Ancillary findings are helpful in the diagnosis of suspicious cases for ACL mucoid degeneration and ACL sprain. The decision tree algorithm offers a practical and successful approach to this issue.

Effect of Fatigue on Ground Reaction Force Variables During Single-leg Landing in Athletes With the History of Anterior Cruciate Ligament Injury

Introduction: Since people experience fatigue after anterior cruciate ligament injury during exercises, it is important to understand how fatigue affects the biomechanical movement patterns. Therefore, this study aimed to investigate the effect of fatigue on ground reaction force variables during single-leg landing in athletes with a history of an anterior cruciate ligament sprain. Methods: it was a case-control study conducted in the University Laboratory. The sample consisted of 36 male athletes who were divided into three groups: 12 people with Anterior Cruciate Ligament Reconstruction (ACLR), 12 people with Anterior Cruciate Ligament Deficiency (ACLD), and 12 people as the control group. Fatigue was induced via the repetitive sets of double-leg squats (n=8), which were interspersed with the sets of countermovement jumps (n=2) and single-leg landings (n=3) until squats were no longer possible. A 2×2 repeated-measures multivariate analysis of variance was used to detect the main effects of group (ACLD, ACLR, control) and fatigue state (prefatigue, postfatigue) on the ground reaction forces variables. Results: The results showed a significant decrease in the peak vertical force and internal-external ground reaction force in the ACLD group after fatigue. Regardless of the fatigue state, the peak vertical ground reaction force in ACLD and ACLR groups was significantly lower than that in the control group. Conclusion: The athletes with the ACL injury, regardless of the selective treatment type, use compensatory strategies to reduce the contact forces on the lower extremity, compared with healthy athletes.

Comparing the Diagnostic Accuracy of Two Selective Tissue Tests for Anterior Cruciate Ligament Injuries: A Critically Appraised Topic

Clinical Question: In patients with acute knee injuries, is there evidence to support that the lever sign test is more accurate in diagnosing an anterior cruciate ligament sprain than the Lachman test? Clinical Bottom Line: The evidence does not indicate that the lever sign test can be used in isolation in lieu of the Lachman test, but there is sufficient evidence to support adding the lever sign test to the examination of potential anterior cruciate ligament sprains.

Knee Injury – Recreational Runner

HISTORY: Case of a 41 year-old army soldier who had an acute bilateral knee giveaway weakness while jogging. After running for a mile, his left knee gaveway and he fell to the floor. He stood up without difficulties and ambulated for a short distance when he fell again due to right knee weakness. He had difficulty ambulating, although he felt no pain. During his ER visit, he had a third fall resulting in a right lateral malleolus fracture. Orthopedics was consulted and performed bilateral patellar tendon repair and right lateral malleolus ORIF. He was discharged home with bilateral hinged knee braces locked at full extension and weight-bearing precautions. Two months post-op, he was admitted to the acute inpatient rehabilitation ward of the VA Caribbean Healthcare. No past medical history of systemic conditions or regular medications. PHYSICAL EXAMINATION: Examination revealed bilateral knee valgus deformity, mild soft tissue swelling and bilateral pes planus. He had full knee extension and limited knee flexion to 90 degrees. Knee special tests were negative for meniscal, cruciate ligament or collateral ligament injury. Neurovascular exam was unremarkable. DIFFERENTIAL DIAGNOSIS: 1. Patellar tendon rupture 2. Quadriceps tendon rupture 3. Anterior cruciate ligament sprain 4. Meniscal injury 5. Collateral ligament sprain TEST AND RESULTS: 1. Bilateral knee MRI: Bilateral full-thickness tear of proximal patellar tendon with cephalad patellar displacement, medial and lateral patellar retinacula tears, and extensive soft tissue edema. Right high-grade partial versus full-thickness anterior cruciate ligament tear and anterior horn lateral meniscus tear. Left posterior horn medial meniscus tear. 2. Bilateral Knee X-ray: Bilateral patella alta. 3. Labs: Essentially normal except for low vitamin D and positive qualitative ANA test. FINAL/WORKING DIAGNOSIS: Atraumatic bilateral patellar tendon rupture TREATMENT AND OUTCOMES: 1. Outpatient-based physical therapy was provided with emphasis on ROM completion, progression of quadriceps strengthening and neuromuscular retraining. 2. He achieved full ROM in both knees and independence in ADL’s and ambulation. 3. Return to recreational sports recommendations included to avoid high impact activities, such as running, until 9-12 months post-op follow up.

An Analysis of Specific Lower Extremity Injury Rates on Grass and FieldTurf Playing Surfaces in National Football League Games

Background: Players in the National Football League (NFL) sustain injuries every season as the result of their participation. One factor associated with the rate of injury is the type of playing surface on which the players participate. Hypothesis: There is no difference in the rate of knee sprains and ankle sprains during NFL games when comparing rates of those injuries during games played on natural grass surfaces with rates of those injuries during games played on the artificial surface FieldTurf. Study Design: Descriptive epidemiology study. Methods: The NFL records injury and exposure (ie, game) data as part of its injury surveillance system. During the 2000-2009 NFL seasons, there were 2680 games (5360 team games) played on grass or artificial surfaces. Specifically, 1356 team games were played on FieldTurf and 4004 team games were played on grass. We examined the 2000-2009 game-related injury data from those games as recorded by the injury surveillance system. The data included the injury diagnosis, the date of injury, and the surface at the time of injury. The injury data showed that 1528 knee sprains and 1503 ankle sprains occurred during those games. We calculated injury rates for knee sprains and ankle sprains—specifically, medial collateral ligament (MCL) sprains, anterior cruciate ligament (ACL) sprains, eversion ankle sprains, and inversion ankle sprains—using incidence density ratios (IDRs). We used a Poisson model and logistic regression odds ratios to validate the IDR analysis. A multivariate logistic regression model was used to adjust the odds ratio for weather conditions. Results: The observed injury rate of knee sprains on FieldTurf was 22% (IDR = 1.22, 95% confidence interval [CI], 1.09-1.36) higher than on grass, and the injury rate of ankle sprains on FieldTurf was 22% (IDR = 1.22, 95% CI, 1.09-1.36) higher than on grass. These differences are statistically significant. Specifically, the observed injury rates of ACL sprains and eversion ankle sprains on FieldTurf surfaces were 67% (P < .001) and 31% (P < .001) higher than on grass surfaces and were statistically significant. The observed injury rates of MCL sprains and inversion ankle sprains were also not significantly higher on FieldTurf surfaces (P = .689 and .390, respectively). Conclusion: Injury rates for ACL sprains and eversion ankle sprains for NFL games played on FieldTurf were higher than rates for those injuries in games played on grass, and the differences were statistically significant.

The Effectiveness of Injury-Prevention Programs in Reducing the Incidence of Anterior Cruciate Ligament Sprains in Adolescent Athletes

There is a high incidence of anterior cruciate ligament (ACL) injury in adolescents participating in pivoting sports such as soccer, basketball, and handball. Most ACL injuries in athletes are noncontact injuries, with a mechanism of sudden deceleration, change in direction, or landing from a jump. These mechanisms coupled with an increase in contraction of the quadriceps have been shown as risk factors for ACL injuries. Injuries to the ACL may require surgery, a long rehabilitation, and the potential for reinjury. Studies have shown reductions in lower extremity injury rates using training protocols that focus on landing mechanics, balance training, strength training, and/or agility training. There has been some thought that starting preventive training programs with adolescent athletes may be the most effective approach to reducing adolescent ACL injuries. Can lower extremity injury-prevention programs effectively reduce ACL injury rates in adolescent athletes?

Snowboarding Injuries

Background: Participation in snowboarding as a winter sport is comparable to alpine skiing concerning the demographics of the participants, risk of injury, and variation in types of injuries sustained. Purpose: To examine the types of snowboarding injuries and changes in injury patterns over time. We also sought to highlight important differences in injury patterns between snowboarders and alpine skiers as affected by age, experience, and sex. Study Design: Case control; Level of evidence, 3. Methods: Data were collected on injured snowboarders and skiers in a base-lodge clinic of a ski resort in Vermont over 18 seasons (1988-2006) and included extensive information about injury patterns, demographics, and experience. Control data were also obtained during this time period to provide information about the population at risk. Results: The injury rates were assessed as mean days between injuries (MDBI). The average MDBI for all injuries among snowboarders was 345 as compared with 400 for skiers (the lower the number, the higher the injury rate). The most common type of injury for snowboarders was a wrist injury (MDBI, 1258), while for skiers, it was an anterior cruciate ligament (ACL) sprain (MDBI, 2332). Wrist injuries accounted for 27.6% of all snowboard injuries and 2.8% of skiing injuries, and ACL injuries composed 1.7% of all snowboard injuries and 17.2% of skiing injuries. Among snowboarders, more wrist injuries, shoulder soft tissue injuries, ankle injuries, concussions, and clavicle fractures were seen, while skiers had more ACL sprains, medial collateral ligament (MCL) sprains of the knee, lateral collateral ligament (LCL) sprains of the knee, lower extremity contusions, and tibia fractures. The trend analysis revealed an increased incidence of clavicle fractures (P < .01) and a decrease in MCL injuries (P < .01) and ankle injuries (P < .025) among snowboarders over time. Skiers had a decrease in thumb metacarpophalangeal-ulnar collateral ligament (MCP-UCL) injuries (P < .001) and MCL injuries of the knee (P < .001) over time. We found the highest rate of injury among young, inexperienced, female snowboarders. When examining the location of injury, 21.8% of snowboard injuries occurred in the terrain park compared with 6.5% of ski injuries. Conclusion: Injury rates in snowboarders have fluctuated over time but currently remain higher than in skiers. Wrist, shoulder, and ankle injuries are more common among snowboarders, while knee ligament injuries are more common in skiers. Injured snowboarders were significantly younger, less experienced, and more likely to be female than injured skiers or snowboard control participants. We did not find any evidence that those who spend time in terrain parks are overrepresented in the injury population.

Thigh Muscle Activity, Knee Motion, and Impact Force During Side-Step Pivoting in Agility-Trained Female Basketball Players

Improving neuromuscular control of hamstrings muscles might have implications for decreasing anterior cruciate ligament injuries in females. To examine the effects of a 6-week agility training program on quadriceps and hamstrings muscle activation, knee flexion angles, and peak vertical ground reaction force. Prospective, randomized clinical research trial. Sports medicine research laboratory. Thirty female intramural basketball players with no history of knee injury (age = 21.07 +/- 2.82 years, height = 171.27 +/- 4.66 cm, mass = 66.36 +/- 7.41 kg). Participants were assigned to an agility training group or a control group that did not participate in agility training. Participants in the agility training group trained 4 times per week for 6 weeks. We used surface electromyography to assess muscle activation for the rectus femoris, vastus medialis oblique, medial hamstrings, and lateral hamstrings for 50 milliseconds before initial ground contact and while the foot was in contact with the ground during a side-step pivot maneuver. Knee flexion angles (at initial ground contact, maximum knee flexion, knee flexion displacement) and peak vertical ground reaction force also were assessed during this maneuver. Participants in the training group increased medial hamstrings activation during ground contact after the 6-week agility training program. Both groups decreased their vastus medialis oblique muscle activation during ground contact. Knee flexion angles and peak vertical ground reaction force did not change for either group. Agility training improved medial hamstrings activity in female intramural basketball players during a side-step pivot maneuver. Agility training that improves hamstrings activity might have implications for reducing anterior cruciate ligament sprain injury associated with side-step pivots.

Magnetic Resonance Imaging Parameters for Assessing Risk of Recurrent Hamstring Injuries in Elite Athletes

Background Magnetic resonance (MR) imaging has established its usefulness in diagnosing hamstring muscle strain and identifying features correlating with the duration of rehabilitation in athletes; however, data are currently lacking that may predict which imaging parameters may be predictive of a repeat strain. Purpose This study was conducted to identify whether any MR imaging-identifiable parameters are predictive of athletes at risk of sustaining a recurrent hamstring strain in the same playing season. Study Design Cohort study; Level of evidence, 3. Methods Forty-one players of the Australian Football League who sustained a hamstring injury underwent MR examination within 3 days of injury between February and August 2002. The imaging parameters measured were the length of injury, cross-sectional area, the specific muscle involved, and the location of the injury within the muscle-tendon unit. Players who suffered a repeat injury during the same season were reimaged, and baseline and repeat injury measurements were compared. Comparison was also made between this group and those who sustained a single strain. Results Forty-one players sustained hamstring strains that were positive on MR imaging, with 31 injured once and 10 suffering a second injury. The mean length of hamstring muscle injury for the isolated group was 83.4 mm, compared with 98.7 mm for the reinjury group (P = .35). In the reinjury group, the second strain was also of greater length than the original (mean, 107.5 mm; P = .07). Ninety percent of players sustaining a repeat injury demonstrated an injury length greater than 60 mm, compared with only 58% in the single strain group (P = .01). Only 7% of players (1 of 14) with a strain <60 mm suffered a repeat injury. Of the 27 players sustaining a hamstring strain >60 mm, 33% (9 of 27) suffered a repeat injury. Of all the parameters assessed, only a history of anterior cruciate ligament sprain was a statistically significant predictor for suffering a second strain during the same season of competition. Conclusion A history of anterior cruciate ligament injury was the only statistically significant risk factor for a recurrent hamstring strain in our study. Of the imaging parameters, the MR length of a strain had the strongest correlation association with a repeat hamstring strain and therefore may assist in identifying which athletes are more likely to suffer further reinjury.

The Relationship between Neurocognitive Function and Noncontact Anterior Cruciate Ligament Injuries

Background Biomechanical analyses suggest that the loss of neuromuscular control is associated with noncontact anterior cruciate ligament sprains; however, previous research has not explored the link between neurocognitive function and unintentional knee injuries. Purpose To determine if athletes who suffer a noncontact anterior cruciate ligament injury demonstrate decreased baseline neurocognitive performance when compared with matched controls. Study Design Case control study; Level of evidence, 3. Methods The baseline scores from a computerized neurocognitive test battery (ImPACT) were analyzed to compare verbal memory, visual memory, processing speed, and reaction time. Eighty intercollegiate athletes who, subsequent to testing, experienced noncontact anterior cruciate ligament injuries, were matched with 80 controls based on height, weight, age, gender, sport, position, and years of experience at the collegiate level. Results Statistical differences were found between the noncontact anterior cruciate ligament injury group and the matched controls on all 4 neurocognitive subtests. Noncontact anterior cruciate ligament—injured athletes demonstrated significantly slower reaction time (F1,158 = 9.66, P = .002) and processing speed (F1,158 = 12.04, P = .001) and performed worse on visual (F1,158 = 19.16, P = .000) and verbal memory (F 1,158 = 4.08, P = .045) composite scores when compared with controls. Conclusion Neurocognitive differences may be associated with the loss of neuromuscular control and coordination errors, predisposing certain intercollegiate athletes to noncontact anterior cruciate ligament injuries.

KNEE INJURY - BASEBALL 830

HISTORY: A 23 year old minor league baseball player collides with a team mate while attempting to field a fly ball. While the player is unsure of the mechanism, he believes his right knee was bent when he collided with the other player. Further, he believes the leg was off the ground, and he remembers no twisting motion during the injury. At the end of the play, he fell on his back with the knee bent in flexion. This could not be described any further. He was able to extend the leg, and no clicking or popping was noted. Evaluation by the trainer showed point tenderness along both the medial and lateral joint line. Laxity of the lateral collateral and anterior cruciate ligaments. Over the last 3 days, swelling has occurred despite icing and immobilization of the knee. The pain has localized to the lateral joint line, femoral condyle and tibial condyle. Player is still reluctant to bear weight with out the immobilizer. PHYSICAL EXAMINATION: Right knee is swollen with ballottable patella, but no discoloration. There is point tenderness along the lateral collateral ligament, as well as the lateral joint line. Range of motion showed extension to zero with recurvatum of about 10 degrees on the left knee. Flexion was to 90 degrees on the right side. Muscle strength was 4+ out of 5 for flexion and extension. Laxity of the right knee noted with varus force. Lachman's, and anterior drawer tests. These test did increase pain. Unable to evaluate McMurray test due to swelling. Slight patella laxity with no apprehension or pain, and normal tracking. Neurovascualar was intact. DIFFERENTIAL DIAGNOSIS- Lateral Collateral Sprain, 2nd to 3rd degree. Possible Anterior Cruciate Ligament Sprain, 2nd to 3rd degree. Possible lateral meniscus tear. TESTS AND RESULTS- Right knee X-ray: normal knee without fracture, dislocation, or avulsion fractures. Right knee MRJ: joint effusion, intact PCL, intact MCL, normal appearing menisci, tear of ACL, LCL, and Tensor Fascia Lata. FINAL DIAGNOSIS- LCL 3rd degree sprain ACL 3rd degree sprain Torn Tensor Fascia Lata TREATMENT- Patient under went arthroscopic evaluation and repair of torn structures. This was followed by aggressive rehabilitation.

A multivariate risk analysis of selected playing surfaces in the National Football League: 1980 to 1989. An epidemiologic study of knee injuries.

This study focuses on the injury rates for natural grass and AstroTurf surfaces and the risk factors of game position and type of play. We examined the game-related knee sprains, medial collateral ligament sprains, and anterior cruciate ligament sprains that occurred in the National Football League during the 1980 to 1989 seasons. The findings are controlled for categories of severity (number of games missed due to injury), position, and situation (rushing or passing) at the time of injury. The analysis of the data incorporates epidemiologic techniques associated with incidence density ratios. The data show that there is a statistically significant difference between the higher AstroTurf injury rates for knee sprains. When knee sprains are separated into medial collateral ligament sprains and anterior cruciate ligament sprains, only the anterior cruciate ligament sprains show a statistically significant higher injury rate for AstroTurf. When simultaneous control variables are considered, significantly more knee sprains occurred to backs on rushing plays and linemen on passing plays. When controlling the data for severity, only the Category II injuries (three or more games missed) sustained by linemen on passing plays had statistically significant higher injury rates for the AstroTurf. For medial collateral ligament sprains, only the Category II injuries for linemen on passing plays remain statistically significant. The data for the ACL sprains show statistically significant differences between the injury rate on natural grass and the injury rate on Astro Turf under conditions of special teams play.

An in vivo strain gage study of elongation of the anterior cruciate ligament.

The purpose of this paper is to study the load-elongation characteristics of a Grade II sprain of the anterior cruciate ligament (ACL) at the time of local anesthesia arthroscopy. The data may be used to increase diagnostic and prognostic accuracy when evaluating Grade II ACL sprains and to structure properly a rehabilitation program following ACL injury. This report is based on the data from two in vivo strain gage studies of Grade II ACL sprains. Following instrumentation of the ligament, several events common to physical examination and rehabilitation programs were tested. The Lachman test produced greater elongation of the anteromedial fibers than did the anterior drawer or pivot shift test. A fairly high force of 80 pounds may be required by the examiner's hands to test satisfactorily the anteromedial fibers in the acutely injured large athlete. The proper order for a rehabilitation program should be crutch walking, cycling, walking, slow running, and faster running. Patients should be cautioned to run on a perfectly level surface. Cycling produced 7% as much elongation as an 80 pound Lachman test, and the one leg half squat 21% as much. Quadriceps rehabilitation can be done more safely using these exercises. Quadriceps exercises by knee extension against a 20 pound weight boot in the range of full extension to 22 degrees flexion created peak elongation of the anteromedial fibers ranging from 87 to 121% of that produced by an 80 pound Lachman test. We recommend that quadriceps exercises and testing by knee extension through a full range of motion not be done during the first year following ACL injury or reconstruction.(ABSTRACT TRUNCATED AT 250 WORDS)