A review of ski injuries resulting in combined injury to the anterior cruciate ligament and medial collateral ligaments

Skill-Specific Differences in Equipment-Related Risk Factors for ACL Injury in Male and Female Recreational Skiers

Background

In recreational alpine skiing, the anterior cruciate ligament (ACL) is affected in approximately 50% of serious knee injuries. There are established sex-based and skill-based differences in ACL injury risk, but the potential impact of equipment used (eg, skis, bindings, and boots) has not been evaluated.

Purpose

To evaluate individual and equipment-related risk factors for an ACL injury depending on sex and skill level.

Study Design

Case-control study; Level of evidence, 3.

Methods

This was a retrospective questionnaire-based, case-control study of female and male skiers with and without ACL injuries during 6 winter seasons (from 2014-2015 to 2019-2020). Demographic data, skill level, equipment specifications, risk-taking behavior, and ownership of ski equipment were recorded. Ski geometry (ski length; sidecut radius; and widths of the tip, waist, and tail) was taken from each participant's ski. The standing heights of the front and back part of the ski binding were measured using a digital sliding caliper, and the standing height ratio was calculated. Abrasion of the ski boot sole was also measured at the toe and heel. Participants were divided by sex into less and more skilled skiers.

Results

A total of 1817 recreational skiers participated in this study, of whom 392 (21.6%) sustained an ACL injury. A greater standing height ratio and more abrasion at the toe of the boot sole were associated with increased ACL injury risk in both sexes, independent of the skill level. Riskier behavior increased the injury risk only in male skiers, independent of the skill level, and longer skis increased the injury risk only in less skilled female skiers. Older age, the use of rented/borrowed skis, and more abrasion at the heel of the boot sole were independent risk factors for ACL injury in the more skilled skiers of both sexes.

Conclusion

Individual and equipment-related risk factors for an ACL injury partly differed according to skill level and sex. Consideration of the demonstrated equipment-related factors should be implemented in order to reduce ACL injuries in recreational skiers.

Method to Investigate Multi-Axis Release Action of Ski Safety Bindings: A New Approach for Testing in Research and Development

The authors developed and elaborated on a new method to release ski bindings by utilizing an industrial robot to simulate release movement showing a spatial repeatability of ± 0.06 mm. The parametric programming of the release parameters gave free control while executing repeatable release tests. A series of different motion patterns were performed, on the one hand, to test the applicability of the setup to the simulation of motion patterns and, on the other, to check for the impact of the ski deformations like ski deflections within the range of −5 mm to −85 mm, on the safety bindings' release forces. As certain falling mechanisms are related to knee injury, which is the most common severe injury in alpine skiing, this testing method can be used to develop related displacement movements in future. This movements do not necessarily accord with the directional release mechanics of safety ski bindings. The authors specify the developed testing apparatus as device for force measurements in 3D with an accuracy of ± 0.5% in boot-sole-plane. The intention behind this development is to enable faster, more versatile and adaptive testing procedures in R&D.

[Osteochondral injury of the femoral insertion of the deep medial collateral ligament of the knee-is there a successful surgical treatment?]

Isolated ruptures of the deep portion of the medial collateral ligament (MCL) without clinical instability can mostly be treated conservatively with good clinical results. A 10-year-old girl was initially also treated conservatively. As symptoms of pain and limited range of motion were not resolved after 3 months of conservative treatment and although there were no signs of instability, it was decided to proceed with the surgical intervention. A small osteochondral fragment on the femoral insertion of the deep MCL (medial meniscofemoral ligament) was removed and the soft tissue portion of the ligament was reinserted in the anatomical footprint. The patient showed complete resolution of the pain and a full range of motion of the knee joint. At the last follow-up 18 months after surgery the patient was completely free of symptoms.

Alpine Skiing Injuries

Context:

Alpine skiing is a popular sport worldwide but has significant risk for injury. The epidemiology of skiing-related injuries has been described, which has led to the identification of risk factors for specific types of injuries.

Evidence Acquisition:

Pertinent literature from peer-reviewed publications was reviewed.

Study Design:

Clinical review.

Level of Evidence:

Level 5.

Results:

The adoption of international standards for ski-boot-binding systems has changed the profile of skiing-related injuries over time, as has the widespread use of helmets. An understanding of mechanisms of injury, risk factors, and preventative measures may decrease the incidence of skiing-related injuries.

Conclusion:

Advances in standards for skiing equipment have been effective at decreasing both the frequency and severity of skiing-related injuries, but additional efforts are required to improve the safety of the sport.

Effects of an 8-Week Body-Weight Neuromuscular Training on Dynamic Balance and Vertical Jump Performances in Elite Junior Skiing Athletes: A Randomized Controlled Trial

Vitale, JA, La Torre, A, Banfi, G, and Bonato, M. Effects of an 8-week body-weight neuromuscular training on dynamic balance and vertical jump performances in elite junior skiing athletes: a randomized controlled trial. J Strength Cond Res 32(4): 911-920, 2018-The aim of the present randomized controlled trial was to evaluate the effects of an 8-week neuromuscular training program focused on core stability, plyometric, and body-weight strengthening exercises on dynamic postural control and vertical jump performance in elite junior skiers. Twenty-four Italian elite junior male skiers were recruited and randomized to either an experimental group (EG), performing neuromuscular warm-up exercises, (EG; n = 12; age 18 ± 1 years; body mass 66 ± 21 kg; height 1.70 ± 0.1 m) or a control group (CG) involved in a standard warm-up (CG; n = 12; age 18 ± 1 years; body mass 62 ± 14 kg; height 1.73 ± 0.1 m). lower quarter Y-Balance Test (YBT), countermovement jump (CMJ), and drop jump (DJ) at baseline (PRE) and at the end (POST) of the experimental procedures were performed. No significant differences between EG and CG were observed at baseline. Results showed that EG achieved positive effects from PRE to POST measures in the anterior, posteromedial, posterolateral directions, and composite score of YBT for both lower limbs, whereas no significant differences were detected for CG. Furthermore, 2-way analysis of variance with Bonferroni's multiple comparisons test did not reveal any significant differences in CMJ and DJ for both EG and CG. The inclusion of an 8-week neuromuscular warm-up program led to positive effects in dynamic balance ability but not in vertical jump performance in elite junior skiers. Neuromuscular training may be an effective intervention to specifically increase lower limb joint awareness and postural control.

Validation of Noncontact Anterior Cruciate Ligament Tears Produced by a Mechanical Impact Simulator Against the Clinical Presentation of Injury

BACKGROUND

Anterior cruciate ligament (ACL) injuries are catastrophic events that affect athletic careers and lead to long-term degenerative knee changes. As injuries are believed to occur within the first 50 milliseconds after initial contact during a rapid deceleration task, impact simulators that rapidly deliver impulse loads to cadaveric specimens have been developed. However, no impactor has reproducibly and reliably created ACL injures in a distribution that mimics clinical observation.

PURPOSE

To better understand ACL injury patterns through a cadaveric investigation that applied in vivo-measured external loads to the knee during simulated landings.

STUDY DESIGN

Controlled laboratory study.

METHODS

A novel mechanical impact simulator reproduced kinetics from in vivo-recorded drop landing tasks on 45 cadaveric knees. Specimens were exposed to a randomized order of variable knee abduction moment, anterior tibial shear, and internal tibial rotation loads before the introduction of an impulse load at the foot. This process was repeated until a hard or soft tissue injury was induced on the joint. Injuries were assessed by an orthopaedic surgeon, and ligament strain was recorded by implanted strain gauges.

RESULTS

The mechanical impact simulator induced ACL injuries in 87% of specimens, with medial collateral ligament (MCL) injuries in 31%. ACL tear locations were 71% femoral side, 21% midsubstance, and 9% tibial side. Peak strain before failure for ACL-injured specimens was 15.3% ± 8.7% for the ACL and 5.1% ± 5.6% for the MCL ( P < .001).

CONCLUSION

The ACL injuries induced by the mechanical impact simulator in the present study have provided clinically relevant in vitro representations of in vivo ACL injury patterns as cited in the literature. Additionally, current ligament strains corroborate the literature to support disproportionate loading of the ACL relative to the MCL during athletic tasks.

CLINICAL RELEVANCE

These findings indicate that the mechanical impact simulator is an appropriate model for examining independent mechanical variables, treatment techniques, and preventive interventions during athletic tasks leading up to and including an ACL injury. Accordingly, this system can be utilized to further parse out contributing factors to an ACL injury as well as assess the shortcomings of ACL reconstruction techniques in a dynamic, simulated environment that is better representative of in vivo injury scenarios.

Biomechanical study of the effect of platelet rich plasma on the treatment of medial collateral ligament lesion in rabbits

PURPOSE

To evaluate the use of platelet-rich plasma in the early stages of healing of traumatic injury of the medial collateral ligament in the knee of rabbits.

METHODS

Thirty rabbits were subjected to surgical lesion of the medial collateral ligament. Of these, 16 were treated with platelet-rich plasma and 14 with saline (control). After 3 and 6 weeks of treatment, 50% of the animals from each group were sacrificed, and biomechanical tests were performed on the injured ligament to compare the tensile strength between the two groups.

RESULTS

Platelet-rich plasma significantly increased the tensile strength of the ligament in the groups treated after3 and 6 weeks. In the group treated with platelet-rich plasma vs. saline, the tensile strength values were 3192.5 ± 189.7 g/f vs. 2851.1 ± 193.1 g/f at3 weeks (p = 0.005) and 5915.6 ± 832.0 g/f vs. 4187.6 ± 512.9 g/f at 6 weeks (p = 0.0001).

CONCLUSION

The use of platelet-rich plasma at the injury site accelerated ligament healing in an animal model, demonstrated by an increase in the tensile strength of the medial collateral ligament.

Anterior cruciate ligament injury/reinjury in alpine ski racing: a narrative review

The purpose of the present review was to: 1) provide an overview of the current understanding on the epidemiology, etiology, risk factors, and prevention methods for anterior cruciate ligament (ACL) injury in alpine ski racing; and 2) provide an overview of what is known pertaining to ACL reinjury and return to sport after ACL injury in alpine ski racing. Given that most of the scientific studies on ACL injuries in alpine ski racing have been descriptive, and that very few studies contributed higher level scientific evidence, a nonsystematic narrative review was employed. Three scholarly databases were searched for articles on ACL injury or knee injury in alpine ski racing. Studies were classified according to their relevance in relation to epidemiology, etiology, risk factors, and return to sport/reinjury prevention. Alpine ski racers (skiers) were found to be at high risk for knee injuries, and ACL tears were the most frequent diagnosis. Three primary ACL injury mechanism were identified that involved tibial internal rotation and anteriorly directed shear forces from ski equipment and the environment. While trunk muscle strength imbalance and genetics were found to be predictive of ACL injuries in development-level skiers, there was limited scientific data on ACL injury risk factors among elite skiers. Based on expert opinion, research on injury risk factors should focus on equipment design, course settings/speed, and athlete factors (eg, fitness). While skiers seem to make a successful recovery following ACL injury, there may be persistent neuromuscular deficits. Future research efforts should be directed toward prospective studies on ACL injury/reinjury prevention in both male and female skiers and toward the effects of knee injury on long-term health outcomes, such as the early development of osteoarthritis. International collaborations may be necessary to generate sufficient statistical power for ACL injury/reinjury prevention research in alpine ski racing.

Epidemiology of intra- and peri-articular structural injuries in traumatic knee joint hemarthrosis - data from 1145 consecutive knees with subacute MRI

OBJECTIVE

In patients with traumatic knee distorsion and hemarthrosis, to investigate the panorama of structural injury, as visualized on magnetic resonance imaging (MRI).

DESIGN

Cohort study of 1145 consecutive patients with traumatic knee distorsion who underwent MRI within median 8 days after injury. We present structural injury as visualized on MRI in relation to age, sex and activity at injury. Population based gender specific annual incidences of common structural injuries were calculated.

RESULTS

The majority of injuries (72%) occurred during sports. Overall, anterior cruciate ligament (ACL) rupture was the most common structural injury (52%), followed by meniscal tear (41%) and lateral patella dislocation (LPD, 17%). Only 12% of ACL tears were isolated with meniscal tear being the most common associated injury (55%). The annual incidence of ACL injury was 77 (70-85, 95% CI) per 100,000 inhabitants with significant differences between men (91, 80-103) and women (63, 53-73). In those aged 16 years and younger, LPD was the most frequent structural injury, both in boys (39%) and girls (43%). In this age group, the annual incidence of LPD was 88 (68-113) and higher in boys (113, 81-154) than in girls (62, 39-95).

CONCLUSIONS

ACL injury occurs in one out of two knees with traumatic hemarthrosis but only 12% are without concomitant structural injury. The overall rate of traumatic knee hemarthrosis and ACL injury is higher in men. In those aged 10-19 years, ACL rupture is more common among girls than boys whereas in those 16 years and younger, LPD is more common among boys than girls.

Risk of Noncontact Anterior Cruciate Ligament Injuries Is Not Associated With Slope and Concavity of the Tibial Plateau in Recreational Alpine Skiers: A Magnetic Resonance Imaging-Based Case-Control Study of 121 Patients

BACKGROUND

Anatomic features of the tibial plateau (ie, posterior slope and medial concavity) have been associated with an increased risk of anterior cruciate ligament (ACL) injuries. However, it remains unclear whether these findings translate to ACL injuries sustained during recreational alpine skiing.

PURPOSE

To investigate the association in recreational alpine skiers between prominent morphological features of the tibial plateau (slope and concavity) and the risk of sustaining an ACL injury during a noncontact incident.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Magnetic resonance imaging data of 121 recreational alpine skiers (74 female, 47 male) after a noncontact knee injury were used for this study. Of these patients, 80 (71% female [n = 57]) had a complete unilateral ACL tear (rupture group), and 41 (41% female [n = 17]) had no indications of an ACL injury (intact group). Two blinded independent examiners measured the slopes of the tibial plateau in the sagittal and coronal planes along with the maximum depth of the medial tibial plateau. Measurements were compared between sexes and between groups using t tests. Logistic regression was used to assess the associations between quantified anatomic indices and the risk of ACL injuries.

RESULTS

Within 121 study patients, female skiers had greater odds of an ACL tear compared with male skiers (odds ratio, 3.5; 95% CI, 1.6-7.8; P < .001). Female skiers were more likely to have a greater lateral tibial slope (LTS) (P = .02) and medial tibial slope (MTS) (P = .02) with a shallower medial tibial depth (MTD) (P = .02) compared with male skiers. No differences between sexes were observed in the coronal tibial slope (CTS) (P = .97). Male and female skiers as a combined group showed no associations between quantified anatomic indices and the risk of sustaining an ACL tear (P > .10). Likewise, no significant differences were observed between the intact versus rupture group in any of the quantified anatomic indices (P > .10). Similar findings were observed when the analyses were repeated on male and female skiers separately.

CONCLUSION

Despite differences between sexes in knee anatomy and the injury risk, the sagittal and coronal slopes (LTS, MTS, CTS), as well as the concavity of the medial tibial plateau (MTD), were not associated with the risk of an ACL tear during a noncontact injury among recreational alpine skiers.

Relative strain in the anterior cruciate ligament and medial collateral ligament during simulated jump landing and sidestep cutting tasks: implications for injury risk

BACKGROUND

The medial collateral (MCL) and anterior cruciate ligaments (ACL) are, respectively, the primary and secondary ligamentous restraints against knee abduction, which is a component of the valgus collapse often associated with ACL rupture during athletic tasks. Despite this correlation in function, MCL ruptures occur concomitantly in only 20% to 40% of ACL injuries.

HYPOTHESIS/PURPOSE

The purpose of this investigation was to determine how athletic tasks load the knee joint in a manner that could lead to ACL failure without concomitant MCL failure. It was hypothesized that (1) the ACL would provide greater overall contribution to intact knee forces than the MCL during simulated motion tasks and (2) the ACL would show greater relative peak strain compared with the MCL during simulated motion tasks.

STUDY DESIGN

Controlled laboratory study.

METHODS

A 6-degrees-of-freedom robotic manipulator articulated 18 cadaveric knees through simulations of kinematics recorded from in vivo drop vertical jump and sidestep cutting tasks. Specimens were articulated in the intact-knee and isolated-ligament conditions. After simulation, each ACL and MCL was failed in uniaxial tension along its fiber orientations.

RESULTS

During a drop vertical jump simulation, the ACL experienced greater peak strain than the MCL (6.1% vs 0.4%; P < .01). The isolated ACL expressed greater peak anterior force (4.8% vs 0.3% body weight; P < .01), medial force (1.6% vs 0.4% body weight; P < .01), flexion torque (8.4 vs 0.4 N·m; P < .01), abduction torque (2.6 vs 0.3 N·m; P < .01), and adduction torque (0.5 vs 0.0 N·m; P = .03) than the isolated MCL. During failure testing, ACL specimens preferentially loaded in the anteromedial bundle failed at 637 N, while MCL failure occurred at 776 N.

CONCLUSION

During controlled physiologic athletic tasks, the ACL provides greater contributions to knee restraint than the MCL, which is generally unstrained and minimally loaded.

CLINICAL RELEVANCE

Current findings support that multiplanar loading during athletic tasks preferentially loads the ACL over the MCL, leaving the ACL more susceptible to injury. An enhanced understanding of joint loading during in vivo tasks may provide insight that enhances the efficacy of injury prevention protocols.

[Recreational and competitive alpine skiing. Typical injury patterns and possibilities for prevention]

Alpine skiing is the most popular winter sport discipline in Germany and is performed by more than 4 million recreational sportsmen and ski racing athletes. Compared to other sports, however, the injury rate in alpine skiing is quite high. Especially the knee joint is the most commonly injured area of the musculoskeletal system. Knee injuries are classified as severe in a high percentage of cases. In this review article, epidemiologic data and typical injury patterns in recreational alpine skiing and in competitive alpine ski racing are compared. In addition, the potentials of preventive methods in alpine skiing are presented and evaluated with a special focus on orthotic devices and protection wear as injury prevention equipment.

Knee Injuries in Downhill Skiers: A 6-Year Survey Study

BACKGROUND

Knee injuries account for approximately one third of injuries in skiers. Researchers have proposed several mechanisms of knee injury in skiers. However, the frequencies of these mechanisms have varied in different studies.

PURPOSE

To identify the most common knee injury mechanisms in recreational downhill skiers and to assess injury frequencies across several demographics.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

Over 6 ski seasons, 541 patients with acute knee injuries completed a survey. Patients selected 1 of 6 injury classifications; age, sex, height, weight, years of experience, ability level, and ski binding release were also recorded.

RESULTS

The overall injury distribution was valgus-external rotation (32.9%), phantom foot (22.5%), hyperextension (19.0%), boot induced (7.8%), collision (2.2%), and other (15.6%). The phantom foot mechanism was most common in ages 30 to 40 years (36.3% of all injuries within this mechanism; P < .01). Children and adults showed no significant difference in distribution of injury mechanism. Of 80 youth skiers, valgus-external rotation was most common (35.4%), followed by phantom foot (25.3%). Adult and youth skiers who identified as "advanced" skiers had a higher prevalence of valgus-external rotation than did less experienced skiers (51.5% of total valgus injuries; P < .01). Bindings released in 19.3% in adults and 53.7% in youths (P < .01) during injury. Female skiers comprised 60.0% of total respondents, but only 39.7% of injuries occurred in female children (P < .01).

CONCLUSION

Valgus-external rotation is the most common injury mechanism for recreational skiers in general. Previous studies have suggested that the phantom foot injury is the most common injury, but in this series, it was the second most common, representing 22.5% of injuries in this study. Individuals between the ages of 30 and 40 years showed an increased risk for the phantom foot mechanism, and the prevalence of injuries was significantly higher for females compared with males in this cohort (P < .01). Children and adults appear to have similar mechanisms for ski-related knee injuries, with valgus-external rotation being most common and advanced skiers having the highest frequency of this mechanism. Binding release was more likely to occur in youth skiers.

Application of triangular vector to functionally reconstruct the medial collateral ligament with double-bundle allograft technique

PURPOSE

The purpose of this study was to present a novel medial collateral ligament (MCL) reconstruction technique and investigate the clinical outcomes of this surgical procedure.

METHODS

From July 2006 to June 2009, 56 patients with medial instability of the knee were treated with MCL reconstruction and followed up for 33 months on average. These patients were divided into 2 groups based on whether anterior cruciate ligament (ACL) injury was present: 27 patients had isolated MCL injury, whereas 29 patients had combined MCL-ACL injury. All patients underwent reconstruction of the MCL with triangular double-bundle allograft, and we evaluated International Knee Documentation Committee (IKDC) scores, anteromedial rotatory instability (AMRI), and excessive knee medial opening (EKMO) both preoperatively and at follow-up.

RESULTS

EKMO was significantly reduced to 2.9 mm at follow-up compared with 10.1 mm preoperatively. The incidence of AMRI was reduced to 9.4% (5 patients) compared with 67.9% (36 patients) preoperatively. Of the patients, 58.9% (33 patients) had a grade A IKDC subjective score and 35.7% (20 patients) had a grade B IKDC subjective score. Most patients had normal or nearly normal range of motion of the knee joint, whereas 4 patients (7.1%) lost more than 6° of range of motion in extension and 2 (3.6%) lost more than 25° in flexion. In 47 patients (83.9%) the symptoms were graded as normal or nearly normal according to IKDC symptom scores. No significant differences in IKDC subjective score, IKDC symptom score, flexion deficit score, AMRI, and EKMO were found between the isolated MCL injury group and the MCL-ACL injury group; however, a significant difference was found in knee extension deficit between groups.

CONCLUSIONS

We have presented a new technique for reconstruction of the MCL with a triangular shape. This technique improved both valgus and rotational stability at short-term outcome. The clinical outcomes using IKDC evaluation indicate that no major difference exists in isolated MCL injury and combined MCL-ACL injury treated with this new technique.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Leg dominance is a risk factor for noncontact anterior cruciate ligament injuries in female recreational skiers

BACKGROUND

In recreational alpine skiing, the knee joint accounts for about one third of all injuries in male and female skiers. However, female recreational skiers have twice the knee injury incidence of male skiers, and the anterior cruciate ligament (ACL) injury risk is 3 times greater in female skiers.

PURPOSE

To evaluate whether leg dominance is a risk factor for noncontact ACL injuries in female recreational skiers.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

The relationships between leg dominance, side of knee injury, and gender were analyzed in 65 male and 128 female skiers suffering from a noncontact ACL rupture.

RESULTS

Anterior cruciate ligament ruptures of the left knee occurred more frequently in female than in male recreational skiers (68% vs 48%, P = .006). For both genders, in 90%, the right leg was the preferred kicking leg. With regard to leg dominance, female skiers suffered more often from ACL ruptures of their nondominant leg than male skiers (63% vs 45%, P = .020). An adjusted odds ratio of 2.0 (95% confidence interval, 1.0-3.8) was calculated.

CONCLUSION

Female skiers showed a 2-fold higher risk of suffering from an ACL rupture on their nondominant leg. Therefore, leg dominance seems to be a risk factor for noncontact ACL injuries in female recreational skiers.

Correlation of axial impact forces with knee joint forces and kinematics during simulated ski-landing

Anterior cruciate ligament (ACL) rupture, during ski-landing, is caused by excessive knee joint forces and kinematics, like anterior tibial translation, internal tibial rotation, and valgus rotation. It is not well understood how these forces/kinematics are directly related to ski-landing impact. In the present study, we applied simulated ski-landing impact to knee specimens, and examined joint force/kinematic responses and their correlations with impact force. Ten human cadaveric knees were subjected to axial impact loading at 70° of flexion to simulate ski-landing impact. Impact was repeated with incremental magnitude until ACL failure. Axial impact forces, anterior-posterior and medial-lateral tibial forces were measured using a tri-axial load cell. Anterior-posterior tibial translation, internal-external tibial rotation, and valgus-varus rotation were determined using a motion-capture system. We found positive correlations of axial impact force with anterior tibial force, medial tibial force, anterior tibial translation, internal tibial rotation, and valgus joint rotation. Axial impact forces were more strongly correlated with anterior tibial forces (R(2) = 0.937 ± 0.050), anterior tibial translation (R(2) = 0.916 ± 0.059), and internal tibial rotation (R(2) = 0.831 ± 0.141) than medial tibial force (R(2) = 0.677 ± 0.193) and valgus joint rotation (R(2) = 0.630+0.271). During ski-landing, these joint forces/kinematics can synergistically act to increase ACL injury risk, whereby the failure mechanism would be dominated by anterior tibial forces, anterior tibial translation, and internal tibial rotation.

Case reports: a Stener-like lesion of the medial collateral ligament of the knee

When the superficial fibers of the medial collateral ligament of the knee are torn without tearing of the deep fibers, the anterior superficial fibers may displace over the pes anserinus tendons, so that healing back to the tibial insertion site may be jeopardized. As only the anterior superficial and not the posterior superficial or deep fibers are disrupted, the knee will not have increased valgus laxity in extension whereas there is not a firm end point in 30 degrees flexion. The clinical findings could be confused with those of a Grade 2 medial collateral ligament sprain that generally is not associated with displacement of the anterior fibers over the pes anserinus tendons. We describe the diagnostic findings confirmed with surgical exploration of two Stener-like disruptions of the medial collateral ligament of the knee.

Functional ultrasonography in the diagnosis of acute anterior cruciate ligament injuries: a field study

Functional ultrasonography is a rapid and inexpensive method of diagnosing anterior cruciate ligament (ACL) injuries. In previous studies, we assessed the diagnostic accuracy of this innovative method by experienced sonographers. The objective of the present study was to investigate whether an examiner without specialist expertise in arthrosonography can achieve similar positive results and whether this technique is effective as a screening tool that can help reduce the number of undetected ACL injuries. After a short period of training, a single examiner prospectively measured anterior tibial translation by ultrasonography in the injured and healthy knees of 41 patients with acute knee trauma. An ACL rupture was presumed to be present if the side-to-side difference in tibial translation exceeded 1 mm (Delta D>1 mm). All patients who were enrolled in the study underwent arthroscopy or at least magnetic resonance imaging (MRI). Ultrasonography revealed the presence of an ACL lesion in 32 of 33 patients with arthroscopically confirmed ACL rupture (sensitivity: 97%, specificity: 87.5%). The mean side-to-side differences (Delta D) between injured (3.8 mm+/-1.5 mm) and uninjured ACLs (0.1 mm+/-0.7 mm) were statistically significant (p<0.05). Our study shows that an examiner without specialist knowledge in ultrasonography can accurately diagnose acute ACL injuries using functional ultrasonography. No additional mechanical tests (KT-1000/KT-2000) or MRI examinations are required. Functional ultrasonography is easy to learn and ensures a high level of diagnostic accuracy. It is well suited for applications in private practices and smaller hospitals with basic medical/surgical care.

Clinically assessed knee joint laxity as a predictor for reconstruction after an anterior cruciate ligament injury: a prospective study of 100 patients treated with activity modification and rehabilitation

BACKGROUND

The association of early knee joint laxity with the need for later reconstruction of the anterior cruciate ligament has not been extensively studied.

HYPOTHESIS

The grade of knee laxity can be used as an early predictor of the need for later reconstruction.

STUDY DESIGN

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

METHODS

One hundred consecutive patients with an acute arthroscopically verified total anterior cruciate ligament rupture were followed prospectively for 15 years. Lachman and pivot-shift tests were performed with the patient under general anesthesia before arthroscopy. After 3 months, the tests were repeated in an ordinary clinical setting. All patients underwent rehabilitation as the first choice of treatment. Anterior cruciate ligament reconstruction was performed only in cases of significant reinjuries (n = 16) or reparable meniscal lesions (n = 6) at a mean of 4 years after injury (range, 4 months-11 years). After 15 years, 94 patients were available for follow-up.

RESULTS

Of the later reconstructed patients (n = 18), 82% had a high-grade Lachman test under anesthesia compared with 63% of the nonreconstructed patients (n = 45; P = .048). At 3 months, 44% of the nonreconstructed patients (n = 32) had a high-grade Lachman test compared with 82% of the reconstructed patients (n = 18; P = .007). Twenty-five patients displayed a normal pivot-shift test at 3 months, of whom 1 underwent later reconstruction (P = .009). A high-grade pivot-shift test at 3 months was associated with an 11.4 relative risk for reconstruction.

CONCLUSION

A positive pivot-shift test at 3 months after injury in an awake patient is the strongest predictor for the future need for reconstruction. Furthermore, a normal pivot-shift test at 3 months indicates a low risk for reconstruction and is characteristic for copers.

Bone bruises associated with ACL rupture: correlation with injury mechanism

BACKGROUND

Different patterns of bone bruising are seen on magnetic resonance imaging in acute anterior cruciate ligament ruptures. These patterns may relate to the mechanism of injury.

HYPOTHESIS

There is a correlation between the mechanism of anterior cruciate ligament injury and bone bruise patterns on magnetic resonance imaging.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Data regarding the mechanism of anterior cruciate ligament rupture were collected prospectively on patients who had anterior cruciate ligament reconstructions. Inclusion criteria included a clear history of mechanism, magnetic resonance imaging within 6 weeks of injury, and no previous knee injury. Patients were divided into noncontact and contact mechanism groups. Bone bruise frequency, location, depth, and intensity were analyzed using magnetic resonance imaging and correlated with the mechanism of injury.

RESULTS

Two hundred fifty-six patients were identified; 100 met the inclusion criteria, 86 were in the noncontact mechanism group, and 14 were in the contact mechanism group. The proportion of bone bruises in the lateral compartment in both groups was higher (P < .001) than in the medial compartment. Bone bruising was more frequent, deeper, and more intense in the noncontact group, with frequency (P = .019) and intensity (P < .001) scores reaching significance at the lateral tibial plateau. Medial compartment bone bruising was seen more frequently than previously reported, particularly in the noncontact group.

CONCLUSION

The noncontact mechanism appears to cause more severe bone bruising in both the medial and lateral compartments.

Bilateral medial tibiofemoral joint stiffness in full extension and 20 degrees of knee flexion

CONTEXT

The valgus stress test is used clinically to assess injury to the medial knee structures in 2 positions: full extension and some degree of flexion. The amount of flexion used to "isolate" the medial collateral ligament is not consistent in the literature, but most studies have shown that stiffness of the ligaments was consistent between the limbs.

OBJECTIVE

To determine (1) if the stiffness of the medial knee structures was the same bilaterally, and (2) if the stiffness was different in full extension compared with 20 degrees of knee flexion.

DESIGN

Criterion standard, before-after design.

SETTING

University research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Both knees of 45 healthy and active volunteers (26 females, 19 males; age = 23.2 +/- 3.96 years, height = 170.6 +/- 7.75 cm, mass = 74.2 +/- 15.14 kg) were studied.

INTERVENTION(S)

A valgus force of 60 N was applied to the lateral aspect of both knees in full extension and in 20 degrees of flexion.

MAIN OUTCOME MEASURE(S)

The slope of the force-strain line of the medial knee during a valgus force was calculated using the LigMaster arthrometer.

RESULTS

Slope means in full extension were 16.1 +/- 3.3 (right knee) and 15.8 +/- 3.1(left knee). Means for 20 degrees of flexion were 12.2 +/- 3.1 (right) and 11.7 +/- 2.8 (left). Stiffness was greater when the knee was in full extension versus 20 degrees of flexion (t(44) = 12.04, P < .001). No difference was noted between the slopes of the 2 knees in extension (t(44) = 0.74, P = .46) or in flexion (t(44) = 1.2, P = .27).

CONCLUSIONS

These findings support the use of the contralateral knee as a control. Further, the valgus stress test should be performed in full extension and in some degree of flexion to assess the different restraining structures of the medial tibiofemoral joint.

Anterior cruciate ligament injury with simultaneous locked bucket-handle tears of both medial and lateral meniscus in a 19-year-old female professional ski racer: a case report

Acute anterior cruciate ligament deficiency combined with simultaneous locked bucket-handle tears of both medial and lateral menisci have rarely been observed. This case report describes the first case of such a combined knee injury in an athlete including injury mechanism, clinical symptoms, specific signs on MRI, and treatment options.

Surgical treatment of multiple knee ligament injuries in 44 patients: 2-8 years follow-up results

The purpose of the study was to evaluate the mid-term results of surgical treatment in different groups of patients with multiple knee ligament injuries. Review of our patients' records revealed that 48 acute and chronic patients were surgically treated for combined knee injury. Due to severe capsular damage in these injuries, open techniques were used. In our treatment protocol, avulsed ligaments and tears of the posterolateral and posteromedial corner were repaired if possible, whereas midsubstance tears of cruciate ligaments and chronic cases were reconstructed with autografts. Postoperatively, an accelerated program of rehabilitation was introduced, aiming to progressively mobilize the joint and improve muscle endurance. For the follow-up evaluation we designed a protocol composed of two parts. In the first part, anatomical lesions were recorded and in the second part, clinical evaluation was performed using the Lysholm score, the Tegner rating system, the IKDC evaluation form, and the KT1000. Student's t tests and chi-square tests were used for data analysis. Forty-eight patients (mean age 28.6+/-11.9 years; 41 males) were classified according to the specific anatomical structures involved. Group A included 12 anterior cruciate ligament (ACL) and medial structure injuries, group B included 11 ACL or posterior cruciate ligament (PCL) ruptures combined with posterolateral injuries, and group C consisted of 25 knee dislocations (ACL and PCL ruptures which might be combined with damage of the collateral ligaments). Thirty-eight patients were surgically treated during the acute phase and ten patients were treated chronically. Forty-four patients (91.6%) were followed up at a mean of 51.3+/-29.9 months. Average Lysholm score was 87+/-12.3; average Tegner score was 5.09+/-2.19 before accident and 4.34+/-2.12 in re-examination; IKDC score was A in 10 cases, B in 22, C in 6, and D in 6. The mean range of motion was 129.9 degrees +/-12.5 degrees . The average loss of extension and flexion were 1.6 degrees +/-2.5 degrees and 7.6 degrees +/-7.9 degrees , respectively. The side-to-side difference in corrected anterior and posterior translation in quadriceps neutral angle and in anterior translation in 30 degrees angle was <3 mm for about 65% of our patients. Surgical treatment of multiple knee ligament injuries, using autografts, provided satisfactory stability, range of motion, and subjective functional results. However, despite the improvement of the quality of life, the preinjury patients' activity level was not fully obtained in re-examination. Patients underwent surgical treatment during the acute phase had better scores in several points, but finally there was no statistical significance between acute and chronic patients. Moreover, no statistically significant differences were observed among the groups with specific damaged anatomical structures.

Conservative and Postoperative Rehabilitation of Isolated and Combined Injuries of the Medial Collateral Ligament

Injuries to the medial collateral ligament (MCL) are very common and there seems to be a consensus supporting the conservative management of grade I and II tears. Grade III tears are also usually treated conservatively unless associated with injuries to the anterior cruciate ligament or posterior cruciate ligament. This article outlines rehabilitation programs for conservative treatment of MCL injuries, and postoperative programs after anterior cruciate ligament or multiple ligament reconstruction. In addition, the use of functional and prophylactic bracing for injuries of the MCL is reviewed.

Physical Examination and Imaging of the Medial Collateral Ligament and Posteromedial Corner of the Knee

The medial side is one of the most commonly injured areas of the knee. The anatomy, diagnosis, and treatment of medial collateral ligament and posteromedial corner (PMC) injuries can be challenging. Understanding the mechanism of injury and performing a thorough physical examination and radiographic evaluation is essential. Frequently, there are concomitant meniscal and other ligament injuries associated with medial-side injuries. Correct identification of all injured structures is important, as missed diagnoses can lead to significant disability. Unrecognized PMC injuries have been implicated in anteromedial rotary instability and failed anterior cruciate ligament reconstructions. Valgus stress testing is the cornerstone for the identification of medial-side knee injuries. Coronal sequences from magnetic resonance imaging are the most useful tool to view the medial collateral ligament and posteromedial structures. Stress x-rays and ultrasound may also be helpful. Thorough physical examination and imaging of injuries to the PMC should dictate the appropriate treatment for optimal results.

Epidemiology of athletic knee injuries: A 10-year study

The knee is an anatomically and biomechanically complex joint. Few studies have been published reporting the type and frequency of knee injuries. However, this information that may help to prevent, diagnose, and treat knee joint injuries. We have documented 17,397 patients with 19,530 sport injuries over a 10-year period of time. 6434 patients (37%) had 7769 injuries (39.8%) related to the knee joint. 68.1% of those patients were men and 31.6% were women. Almost 50% of the patients were between the ages of 20-29 (43.1%) at the time of injury. The injuries documented were ACL lesion (20.3%), medial meniscus lesion (10.8%), lateral meniscus lesion (3.7%), MCL lesion (7.9%), LCL lesion (1.1%), and PCL lesion (0.65%). The activities leading to most injuries were soccer (35%) and skiing (26%). LCL injury was associated with tennis and gymnastics, MCL with judo and skiing, ACL with handball and volleyball, PCL with handball, lateral meniscus with gymnastics and dancing, and medial meniscus with tennis and jogging.

Erratum to "The change in length of the medial and lateral collateral ligaments during in vivo knee flexion"

The collateral ligaments of the knee are important in maintaining knee stability. However, little data has been reported on the in vivo function of the collateral ligaments. The objective of this study was to investigate the change in length of different fiber bundles of the medial collateral ligament (MCL), deep fibers of the MCL (DMCL) and the lateral collateral ligament (LCL) during in vivo knee flexion. The knees of five healthy subjects were scanned using magnetic resonance imaging. These images were used to create three-dimensional models of the tibia and femur, including the insertions of the collateral ligaments. The MCL, DMCL, and LCL were each divided into three equal portions: an anterior bundle, a middle bundle and a posterior bundle. Next, the subjects were imaged from two orthogonal directions using fluoroscopy while performing a quasi-static lunge from 0 degrees to 90 degrees of flexion. The models and fluoroscopic images were then used to reproduce the in vivo motion of the knee. From these models, the length of each bundle of each ligament was measured as a function of flexion. The length of the anterior bundle of the MCL did not change significantly with flexion. The length of the posterior bundle of the MCL consistently decreased with flexion (p < 0.05). The change in length of the DMCL with flexion was similar to the trend observed for the MCL. The length of the anterior bundle of the LCL increased with flexion and the length of the posterior bundle decreased with flexion. These data indicate that the collateral ligaments do not elongate uniformly as the knee is flexed, with different bundles becoming taut and slack. These data may help to provide a better understanding of the in vivo function of the collateral ligaments and be used to improve surgical reconstructions of the collateral ligaments. Furthermore, the data suggest that the different roles of various portions of the collateral ligaments along the flexion path should be considered before releasing the collateral ligaments during knee arthroplasty.