Return to play and future ACL injury risk after ACL reconstruction in soccer athletes from the Multicenter Orthopaedic Outcomes Network (MOON) group

Factors associated with additional anterior cruciate ligament reconstruction and register comparison: a systematic review on the Scandinavian knee ligament registers

Objective

To present an overview of the Scandinavian knee ligament registers with regard to factors associated with additional ACL reconstruction, and studies comparing the Scandinavian registers with other knee ligament registers.

Design

Systematic review.

Data sources

Four electronic databases: PubMed, EMBASE, the Cochrane Library and AMED were searched, and 157 studies were identified. Two reviewers independently screened titles, abstracts and full-text studies for eligibility. A modified version of the Downs and Black checklist was applied for quality appraisal.

Eligibility criteria for selecting studies

Eligible studies were those published since the establishment of the Scandinavian registers in 2004, which reported factors associated with additional ACL reconstruction and compared data from other registers.

Results

Thirty-one studies met the inclusion criteria and generally displayed good reporting quality. Adolescent age (<20 years) was the most common factor associated with additional ACL reconstruction. The choice of hamstring tendon graft compared with patella tendon, transportal femoral tunnel drilling, smaller graft diameter and utilisation of suspensory fixation devices were associated with additional ACL reconstruction. Concomitant cartilage injury decreased the likelihood of additional ACL reconstruction. Patient sex alone did not influence the likelihood. The demographics of patients undergoing ACL reconstruction in the Scandinavian registers are comparable to registers in other geographical settings. However, there are differences in surgical factors including the presence of intra-articular pathology and graft choice.

Summary

The studies published from the Scandinavian registers in general have a high reporting quality when regarded as cohort studies. Several factors are associated with undergoing additional ACL reconstruction. The results from the registers may help facilitate treatment decisions.

Sex-based Differences in Common Sports Injuries

The patient's sex plays an important role in mediating the risk for, and experience of, disease. Injuries of the musculoskeletal system are no exception to this phenomenon. Increasing evidence shows that the incidence, clinical presentation, and treatment outcomes for male and female patients with common sports injuries may vary widely. Stress fracture, which is associated with the female athlete triad, is a sports injury with known sex-based differences. Other common sports-related injuries may also have distinct sex-based differences. Understanding these differences is important to optimize each patient's musculoskeletal care.

Multivariate genome-wide association analysis identifies novel and relevant variants associated with anterior cruciate ligament rupture risk in the dog model

Background

Anterior cruciate ligament rupture (ACLR) is a debilitating and potentially life-changing condition in humans, as there is a high prevalence of early-onset osteoarthritis after injury. Identification of high-risk individuals before they become patients is important, as post-treatment lifetime burden of ACLR in the USA ranges from $7.6 to $17.7 billion annually. ACLR is a complex disease with multiple risk factors including genetic predisposition. Naturally occurring ACLR in the dog is an excellent model for human ACLR, as risk factors and disease characteristics in humans and dogs are similar. In a univariate genome-wide association study (GWAS) of 237 Labrador Retrievers, we identified 99 ACLR candidate loci. It is likely that additional variants remain to be identified. Joint analysis of multiple correlated phenotypes is an underutilized technique that increases statistical power, even when only one phenotype is associated with the trait. Proximal tibial morphology has been shown to affect ACLR risk in both humans and dogs. In the present study, tibial plateau angle (TPA) and relative tibial tuberosity width (rTTW) were measured on bilateral radiographs from purebred Labrador Retrievers that were recruited to our initial GWAS. We performed a multivariate genome wide association analysis of ACLR status, TPA, and rTTW.

Results

Our analysis identified 3 loci with moderate evidence of association that were not previously associated with ACLR. A locus on Chr1 associated with both ACLR and rTTW is located within ROR2, a gene important for cartilage and bone development. A locus on Chr4 associated with both ACLR and TPA resides within DOCK2, a gene that has been shown to promote immune cell migration and invasion in synovitis, an important predictor of ACLR. A third locus on Chr23 associated with only ACLR is located near a long non-coding RNA (lncRNA). LncRNA’s are important for regulation of gene transcription and translation.

Conclusions

These results did not overlap with our previous GWAS, which is reflective of the different methods used, and supports the need for further work. The results of the present study are highly relevant to ACLR pathogenesis, and identify potential drug targets for medical treatment.

Electronic supplementary material

The online version of this article (10.1186/s12863-018-0626-7) contains supplementary material, which is available to authorized users.

Anterior cruciate ligament repair - past, present and future

Background

This article provides a detailed narrative review on the history and current concepts surrounding ligamentous repair techniques in athletic patients. In particular, we will focus on the anterior cruciate ligament (ACL) as a case study in ligament injury and ligamentous repair techniques. PubMed (MEDLINE), EMBASE and Cochrane Library databases for papers relating to primary anterior cruciate ligament reconstruction were searched by all participating authors. All relevant historical papers were included for analysis. Additional searches of the same databases were made for papers relating to biological enhancement of ligament healing.

Current standard

The poor capacity of the ACL to heal is one of the main reasons why the current gold standard surgical treatment for an ACL injury in an athletic patient is ACL reconstruction with autograft from either the hamstrings or patella tendon. It is hypothesised that by preserving and repairing native tissues and negating the need for autograft that primary ACL repair may represent a key step change in the treatment of ACL injuries.

History of primary ACL repair

The history of primary ACL repair will be discussed and the circumstances that led to the near-abandonment of primary ACL repair techniques will be reviewed.

New primary repair techniques

There has been a recent resurgence in interest with regards to primary ACL repair. Improvements in imaging now allow for identification of tear location, with femoral-sided injuries, being more suitable for repair. We will discuss in details strategies for improving the mechanical and biological environment in order to allow primary healing to occur.

In particular, we will explain mechanical supplementation such as Internal Brace Ligament Augmentation and Dynamic Intraligamentary Stabilisation techniques. These are novel techniques that aim to protect the primary repair by providing a stabilising construct that connects the femur and the tibia, thus bridging the repair.

Bio enhanced repair

In addition, biological supplementation is being investigated as an adjunct and we will review the current literature with regards to bio-enhancement in the form platelet rich plasma, bio-scaffolds and stem cells. On the basis of current evidence, there appears to be a role for bio-enhancement, however, this is not yet translated into clinical practice.

Conclusions

Several promising avenues of further research now exist in the form of mechanical and biological augmentation techniques. Further work is clearly needed but there is renewed interest and focus for primary ACL repair that may yet prove the new frontier in ligament repair.

Epidemiology of Recurrent Anterior Cruciate Ligament Injuries in National Collegiate Athletic Association Sports: The Injury Surveillance Program, 2004-2014

Background:

An anterior cruciate ligament (ACL) rupture is a serious injury that can be career-ending in collegiate athletics. A rerupture after primary ACL reconstruction occurs in 1% to 11% of all athletes.

Purpose:

To describe the epidemiology of recurrent ACL ruptures in the 25 National Collegiate Athletic Association (NCAA) sports in the NCAA Injury Surveillance Program (ISP) and to identify and compare sport-specific risk factors for a recurrent ACL rupture.

Study Design:

Descriptive epidemiology study.

Methods:

Athletes who experienced a primary or recurrent ACL rupture between 2004 and 2014 were identified using data from the NCAA ISP. ACL ruptures occurred in 12 of 25 sports during the study period. We assessed the rates and patterns of primary and recurrent ACL ruptures and reported them as events per 10,000 athlete-exposures (AEs). Sex-comparable sports were compared using rate ratios. Rupture rates were compared using odds ratios, with P values <.05 indicating significance. Regular-season and postseason data were combined because of low counts of postseason events.

Results:

Of 350,416 AEs, there were 1105 ACL ruptures, 126 of which were recurrent. The highest rates of recurrent ACL ruptures (per 10,000 AEs) were among male football players (15), female gymnasts (8.2), and female soccer players (5.2). Of sports played by athletes of both sexes, women’s soccer had a significantly higher rate of recurrent ACL ruptures than men’s soccer (rate ratio, 3.8 [95% CI, 1.3-15]). Among all sports, men had a significantly higher rate of recurrent ACL ruptures (4.3) than women (3.0) (P = .04). Overall, the ratio of recurrent to primary ACL ruptures decreased over the 10-year study period. Both women and men had a decreasing trend of recurrent to primary ACL ruptures, although women had a steeper decrease.

Conclusion:

These data can help identify athletes who are most at risk of recurrent ACL ruptures after ACL reconstruction and who may benefit from injury prevention programs.

Cross-education does not accelerate the rehabilitation of neuromuscular functions after ACL reconstruction: a randomized controlled clinical trial

PURPOSE

Cross-education reduces quadriceps weakness 8 weeks after anterior cruciate ligament (ACL) surgery, but the long-term effects are unknown. We investigated whether cross-education, as an adjuvant to the standard rehabilitation, would accelerate recovery of quadriceps strength and neuromuscular function up to 26 weeks post-surgery.

METHODS

Group allocation was randomized. The experimental (n = 22) and control (n = 21) group received standard rehabilitation. In addition, the experimental group strength trained the quadriceps of the non-injured leg in weeks 1-12 post-surgery (i.e., cross-education). Primary and secondary outcomes were measured in both legs 29 ± 23 days prior to surgery and at 5, 12, and 26 weeks post-surgery.

RESULTS

The primary outcome showed time and cross-education effects. Maximal quadriceps strength in the reconstructed leg decreased 35% and 12% at, respectively, 5 and 12 weeks post-surgery and improved 11% at 26 weeks post-surgery, where strength of the non-injured leg showed a gradual increase post-surgery up to 14% (all p ≤ 0.015). Limb symmetry deteriorated 9-10% more for the experimental than control group at 5 and 12 weeks post-surgery (both p ≤ 0.030). One of 34 secondary outcomes revealed a cross-education effect: Voluntary quadriceps activation of the reconstructed leg was 6% reduced for the experimental vs. control group at 12 weeks post-surgery (p = 0.023). Both legs improved force control (22-34%) and dynamic balance (6-7%) at 26 weeks post-surgery (all p ≤ 0.043). Knee joint proprioception and static balance remained unchanged.

CONCLUSION

Standard rehabilitation improved maximal quadriceps strength, force control, and dynamic balance in both legs relative to pre-surgery but adding cross-education did not accelerate recovery following ACL reconstruction.

Progressive Changes in Walking Kinematics and Kinetics After Anterior Cruciate Ligament Injury and Reconstruction: A Review and Meta-Analysis

CONTEXT

  Anterior cruciate ligament (ACL) injury and ACL reconstruction (ACLR) result in persistent alterations in lower extremity movement patterns. The progression of lower extremity biomechanics from the time of injury has not been described.

OBJECTIVE

  To compare the 3-dimensional (3D) lower extremity kinematics and kinetics of walking among individuals with ACL deficiency (ACLD), individuals with ACLR, and healthy control participants from 3 to 64 months after ACLR.

DATA SOURCES

  We searched PubMed and Web of Science from 1970 through 2013.

STUDY SELECTION AND DATA EXTRACTION

  We selected only articles that provided peak kinematic and kinetic values during walking in individuals with ACLD or ACLR and comparison with a healthy control group or the contralateral uninjured limb.

DATA SYNTHESIS

  A total of 27 of 511 identified studies were included. Weighted means, pooled standard deviations, and 95% confidence intervals were calculated for the healthy control, ACLD, and ACLR groups at each reported time since surgery. The magnitude of between-groups (ACLR versus ACLD, control, or contralateral limb) differences at each time point was evaluated using Cohen d effect sizes and associated 95% confidence intervals. Peak knee-flexion angle (Cohen d = -0.41) and external knee-extensor moment (Cohen d = -0.68) were smaller in the ACLD than in the healthy control group. Peak knee-flexion angle (Cohen d range = -0.78 to -1.23) and external knee-extensor moment (Cohen d range = -1.39 to -2.16) were smaller in the ACLR group from 10 to 40 months after ACLR. Reductions in external knee-adduction moment (Cohen d range = -0.50 to -1.23) were present from 9 to 42 months after ACLR.

CONCLUSIONS

  Reductions in peak knee-flexion angle, external knee-flexion moment, and external knee-adduction moment were present in the ACLD and ACLR groups. This movement profile during the loading phase of gait has been linked to knee-cartilage degeneration and may contribute to the development of osteoarthritis after ACLR.

Outcomes and Return to Sport After Revision Anterior Cruciate Ligament Reconstruction in Adolescent Athletes

Background

The number of adolescent anterior cruciate ligament (ACL) injuries is rising with increased participation in higher level athletics at earlier ages. With an increasing number of primary ACL reconstructions (ACLRs) comes a rise in the incidence of revision ACLRs.

Purpose

To evaluate the clinical results of revision ACLR across a group of high-level adolescent athletes with at least 2-year follow-up.

Study Design

Case series; Level of evidence, 4.

Methods

A retrospective review of 21 adolescent athletes (age range, 10-19 years) who underwent revision ACLR with at least 2-year follow-up was conducted. Patient-reported outcome measures (PROMs) included the International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, Lysholm knee scoring scale, Tegner activity level scale, and modified Cincinnati Knee Rating System. Return to sport (RTS) and overall patient satisfaction were also assessed.

Results

The mean age at the time of surgery was 16.5 years (range, 14-19 years), and the mean follow-up was 46.4 months (range, 24-97 months); 42.9% of patients were female, and 52.4% of patients participated in collision sports. The mean time to failure after primary ACLR was 13.1 ± 8.0 months, and the most common mechanism of failure was noncontact in at least 66.7% of cases. The revision graft type included bone-patellar tendon-bone (BPTB) in 71.4% of cases; 26.7% of BPTB grafts were from the contralateral extremity. Concomitant procedures were performed for intra-articular lesions in 71.4% of patients. The mean patient satisfaction rate was 95.3%. There were 3 cases of a graft reinjury at a mean of 25 months postoperatively. The mean PROM scores were as follows: IKDC, 87.5 ± 12.7; Tegner, 7.2 ± 2.0; Lysholm, 93.7 ± 9.8; and Cincinnati, 93.4 ± 10.0. Of those attempting to RTS, 68.4% of patients successfully returned at the same level of competition. Patients with a lateral compartment chondral injury were less likely to RTS (P < .05). Independent variables shown to have no significant relationship to PROMs or RTS included age, follow-up, sport classification, associated meniscal tears, revision graft size/type, and concomitant procedures.

Conclusion

Revision ACLR can be an effective surgical option in adolescents participating in collision and contact sports, with good to excellent subjective outcome scores. At a minimum 2-year follow-up, a graft rupture after revision ACLR occurred in 14% of cases. Of the athletes attempting to RTS, 68.4% returned to their preinjury level of competition.

A Novel Mass-Spring-Damper Model Analysis to Identify Landing Deficits in Athletes Returning to Sport After Anterior Cruciate Ligament Reconstruction

Schneider, DK, Gokeler, A, Otten, E, Ford, KR, Hewett, TE, Divine, JG, Colosimo, AJ, Heidt, RS, and Myer, GD. A Novel mass-spring-damper model analysis to identify landing deficits in athletes returning to sport after anterior cruciate ligament reconstruction. J Strength Cond Res 31(9): 2590-2598, 2017-A mass-spring-damper (MSD) model may serve as an extension of biomechanical data from 3-dimensional motion analysis and epidemiological data which helps to delineate populations at risk for anterior cruciate ligament (ACL) injuries. The purpose of this study was to evaluate such a model. Thirty-six ACL reconstruction (ACLR) group subjects and 67 controls (CTRL) completed single-leg drop landing and single-leg broad jump tasks. Landing ground reaction force data were collected and analyzed with an MSD model. Medians, interquartile ranges, and limb symmetry indices (LSIs) were calculated and comparisons were made within and between groups. During a single-leg drop landing, the ACLR group had a lower spring LSI than the CTRL group (p = 0.015) and landed with decreased stiffness in the involved limb relative to the uninvolved limb (p = 0.021). The ACLR group also had an increased damping LSI relative to the CTRL group (p = 0.045). The ACLR subjects landed with increased stiffness (p = 0.006) and decreased damping (p = 0.003) in their involved limbs compared to CTRL subjects' nondominant limbs. During a single-leg forward broad jump, the ACLR group had a greater spring LSI value than the CTRL group (p = 0.045). The CTRL group also recorded decreased damping values in their nondominant limbs compared with the involved limbs of the ACLR group (p = 0.046). Athletes who have undergone ACLR display different lower-limb dynamics than healthy controls, according to an MSD model. Quadriceps dominance and leg dominance are components of ACLR athletes' landing strategies and may be identified with an MSD model and addressed during rehabilitation.

Anterior cruciate ligament ruptures in German elite soccer players: Epidemiology, mechanisms, and return to play

BACKGROUND

Anterior cruciate ligament ruptures (ACLRs) are severe sports-related injuries with significant consequences for affected players and teams. This study aims to identify the epidemiology and injury-related lay-off after ACLR in professional male soccer players from the first-division German Bundesliga.

METHODS

Exposure times and incidence of anterior cruciate ligament ruptures were collected during 7.5 consecutive seasons using two media-based registers.

RESULTS

A total of 72 total ACLRs were registered in 66 different players with an incidence of 0.040 per 1000h of exposure (95% CI 0.009-0.12). On average there were 9.6 ACLRs per season and 0.53 per team and season. The mean age of players affected was 24 (standard deviation±3.6) years. The number of ACLRs recorded per season fluctuated during the period observed. Goalkeepers are significantly (P<0.05) less prone to suffer an ACLR compared to outfield players.

CONCLUSIONS

Understanding ACLR loading mechanisms, knowing risk factors for the injury and mean off time after ACLR are essential information for the coach, the medical staff, the elite soccer players, the insurance and team managers. Our results are in accordance with reports based on information from medical team staff. Therefore, our analysis of ACLR based on media sources may serve as an alternative for injury reports in elite soccer. The information of this study may be helpful for the medical staff taking care of professional soccer players and for orthopedic surgeons performing ACL reconstructions in this patient population.

20-Year Outcomes of Anterior Cruciate Ligament Reconstruction With Hamstring Tendon Autograft: The Catastrophic Effect of Age and Posterior Tibial Slope

BACKGROUND

No well-controlled studies have compared the long-term outcome of anterior cruciate ligament (ACL) reconstruction with hamstring tendon autograft between adolescents and adults. Increased posterior tibial slopes (PTSs) have been reported in the ACL-injured versus controls, but the effect of PTS on the outcome after reconstruction is relatively unexplored.

PURPOSE

To compare the prospective longitudinal outcome of "isolated" ACL ruptures treated with anatomic endoscopic ACL reconstruction using hamstring tendon autograft over 20 years in adolescent and adult cohorts and to examine factors for repeat ACL injury.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

A single-surgeon series of 200 consecutive patients undergoing isolated primary ACL reconstruction with hamstring tendon autograft were prospectively studied. Subjects were assessed preoperatively and at 2, 7, 15, and 20 years postoperatively. Outcomes included International Knee Documentation Committee (IKDC) Knee Evaluation, IKDC subjective scores, KT-1000 instrumented laxity testing, and radiological evaluation of degenerative change and medial tibial slope. Twenty-year outcomes were compared between those who underwent surgery at the age of 18 years or younger (adolescent group, n = 39) and those who underwent surgery when older than 18 years (adult group, n = 161).

RESULTS

At 20 years, 179 of 200 subjects were reviewed (89.5%). ACL graft rupture occurred in 37 subjects and contralateral ACL injury in 22 subjects. Of those with intact ACL grafts at 20 years, outcomes were not statistically different between adolescents and adults for the variables of IKDC subjective score ( P = .29), return to preinjury activity level ( P = .84), current activity level ( P = .69), or degree of radiological degenerative change at 20 years ( P = .51). The adolescent group had a higher proportion of grade 1 ligamentous laxity testing compared with the adult group ( P = .003). Overall, ACL graft survival at 20 years was 86% for adults and 61% for adolescents (hazard ration, 3.3; P = .001). The hazard for ACL graft rupture was increased by 4.8 in adolescent males and 2.5 in adolescent females compared with adults. At 20 years, the ACL survival for adolescents with a PTS of ≥12° was 22%. The hazard for ACL graft rupture was increased by 11 in adolescents with a PTS of ≥12° ( P = .001) compared with adults with a PTS <12°.

CONCLUSION

Repeat ACL injury after isolated ACL reconstruction is common, occurring in 1 in 3 over 20 years. In the absence of further injury, isolated ACL reconstruction using this technique was associated with good long-term outcomes with respect to patient-reported outcomes and return to sports, regardless of age. However, mild ligament laxity and ACL graft rupture after ACL reconstruction are significantly more common in adolescents, especially adolescent males, compared with adults. PTS of 12° or more is the strongest predictor of repeat ACL injury, and its negative effect is most pronounced in adolescents.

Quadriceps Strength Deficit at 6 Months After ACL Reconstruction Does Not Predict Return to Preinjury Sports Level

Background:

There is a lack of literature-based objective criteria for return to sport after anterior cruciate ligament (ACL) injury. Establishing such objective criteria is crucial to improving return to sport after ACL reconstruction (ACLR).

Hypotheses:

Patients who return to their preinjury level of sport will have higher isokinetic, postural stability, and drop vertical jump test scores 6 months after surgery and greater patient satisfaction compared with those who did not. Additionally, quadriceps strength deficit cutoff values of 80% and 90% would differentiate patients who returned to preinjury sports level from those who did not.

Study Design:

Cohort study.

Level of Evidence:

Level 3.

Methods:

A retrospective search was conducted to identify all patients who underwent ACLR and completed isokinetic evaluation, postural stability analysis, and drop vertical jump testing at 6 months postoperatively. Patients were asked to complete 3 questionnaires at a minimum 1 year after surgery. Chi-square and logistic regression analyses were used for categorical dependent variables, while the Student t test, Pearson correlation, or analyses of variance with Bonferroni post hoc testing were used for continuous dependent variables. A post hoc power analysis was completed. Based on the results regarding correlations between return to preinjury level and all other variables, effect sizes from 0.24 to 3.03 were calculated. With these effect sizes, an alpha of 0.05 and sample size of 58, a power ranging from 0.15 to 0.94 was calculated.

Results:

The rates of return to preinjury level and to any sports activity were 53.4% and 84.4%. Those who were able to return to their preinjury level of sport (n = 33) showed significantly higher Lysholm (91.6 ± 9.7 vs 76.7 ± 15.4) and International Knee Documentation Committee (IKDC) (83.6 ± 10.6 vs 69.8 ± 14.6) values compared with those who were unable to return to their preinjury level of sport (n = 25) (P < 0.001). No significant differences were found for the clinical evaluations between those who were and those who were not able to return at the same level for the clinical evaluations (isokinetic evaluation, postural stability, drop vertical jump test) (P > 0.05). No significant differences were found when comparing quadriceps strength deficit with cutoff values of 80% and 90% for return to preinjury activity level (Tegner), Lysholm, and IKDC scores.

Conclusion:

Quadriceps strength deficit, regardless of cutoff value (80% or 90%), at 6 months after ACLR does not predict return to preinjury level of sport. Patients who returned to sport at their preinjury level were more satisfied with their reconstruction compared with those who did not.

Clinical Relevance:

Quadriceps strength deficit is not a reliable predictor of return to sports, and therefore it should not be used as the single criterion in such evaluations.

Clinical outcomes of extra-articular tenodesis/anterolateral reconstruction in the ACL injured knee

PURPOSE

The role of concomitant extra-articular procedures in improving the outcome of ACL reconstruction has experienced a recent resurgence in interest. The aim of this article is to highlight the differences in philosophies and outcomes of historical lateral extra-articular tenodesis (LET) and contemporary, anterolateral reconstruction.

METHODS

A narrative review was performed using PubMed/MEDLINE using the keywords "lateral extra-articular tenodesis" and "anterolateral ligament reconstruction".

RESULTS

Results of search strategy: Thirty-seven studies [13 reporting clinical outcomes of isolated LET in ACL deficient knees and 24 comparing isolated anterior cruciate ligament reconstruction (ACLR) with ACLR + LET] and 1 study on anterolateral ligament (ALL) reconstruction were identified as relevant and included in the review. Results of literature review: Isolated extra-articular reconstructions are rarely performed in contemporary practice. They are associated with a high rate of persistent anterior instability and early degenerative change. Combined ACL reconstruction and lateral extra-articular tenodeses results in a significant reduction in the prevalence of residual pivot shift, but the majority of the studies do not demonstrate any significant difference with respect to patient-reported outcome measures and return to sport. Although several authors report a trend towards decreased graft rupture rates, significant differences were not demonstrated in most studies. In a single clinical study, combined anatomic ACL and anterolateral ligament reconstruction was reported to be associated with a threefold reduction in graft rupture rates and improved return to sport compared to isolated ACL graft choices.

CONCLUSIONS

Historically performed, combined ACL reconstruction and lateral extra-articular tenodeses are associated with improved knee kinematics. Although trends towards decreased graft rupture rates are reported by several authors, the majority did not demonstrate a significant difference, likely as a result of small and underpowered studies using post-operative immobilisation and delayed rehabilitation protocols. More recently, combined ACLR and ALL reconstruction has been shown to be associated with significant improvements in graft failure and return to sport rates when compared to isolated ACLR. However, these results are from a single clinical series with only medium-term follow-up.

LEVEL OF EVIDENCE

IV.

A Prospective Evaluation of Femoral Tunnel Placement for Anatomic Anterior Cruciate Ligament Reconstruction Using 3-Dimensional Magnetic Resonance Imaging

BACKGROUND

The recent emphasis on anatomic reconstruction of the anterior cruciate ligament (ACL) is well supported by clinical and biomechanical research. Unfortunately, the location of the native femoral footprint can be difficult to see at the time of surgery, and the accuracy of current techniques to perform anatomic reconstruction is unclear.

PURPOSE

To use 3-dimensional magnetic resonance imaging (3D MRI) to prospectively evaluate patients with torn ACLs before and after reconstruction and thereby assess the accuracy of graft position on the femoral condyle.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Forty-one patients with unilateral ACL tears were recruited into the study. Each patient underwent 3D MRI of both the injured and uninjured knees before surgery. The contralateral (uninjured) knee was used to define the patient's native footprint. Patients then underwent ACL reconstruction, and the injured knee underwent reimaging after surgery. The location and percentage overlap of the reconstructed femoral footprint were compared with the patient's native footprint.

RESULTS

The center of the native ACL femoral footprint was a mean 12.0 ± 2.6 mm distal and 9.3 ± 2.2 mm anterior to the apex of the deep cartilage. The position of the reconstructed graft was significantly different, with a mean distance of 10.8 ± 2.2 mm distal ( P = .02) and 8.0 ± 2.3 mm anterior ( P = .01). The mean distance between the center of the graft and the center of the native ACL femoral footprint (error distance) was 3.6 ± 2.6 mm. Comparing error distances among the 4 surgeons demonstrated no significant difference ( P = .10). On average, 67% of the graft overlapped within the native ACL femoral footprint.

CONCLUSION

Despite contemporary techniques and a concerted effort to perform anatomic ACL reconstruction by 4 experienced sports orthopaedic surgeons, the position of the femoral footprint was significantly different between the native and reconstructed ACLs. Furthermore, each surgeon used a different technique, but all had comparable errors in their tunnel placements.

Altered movement during single leg hop test after ACL reconstruction: implications to incorporate 2-D video movement analysis for hop tests

PURPOSE

There is a lack of objective factors which can be used in guiding the return to sport (RTS) decision after an anterior cruciate ligament reconstruction (ACLR). The purpose of the current study was to conduct qualitative analysis of the single leg hop (SLH) in patients after ACLR with a simple and clinical friendly method and to compare the possible difference in movement pattern between male and female patients.

METHODS

Sixty-five patients performed the single leg hop (SLH) test at 6.8 ± 1.0 months following isolated ACLR. Digital video camcorders recorded frontal and sagittal plane views of the patient performing the SLH. Knee flexion at initial contact (IC), peak knee flexion, knee flexion range of motion (RoM), and knee valgus RoM were calculated. In addition, limb symmetry index (LSI) scores were calculated.

RESULTS

No differences were found in movement pattern between males and females. Movement analysis revealed that males had a decrease in knee flexion at IC (p = 0.018), peak knee flexion (p = 0.002), and knee flexion RoM (p = 0.017) in the injured leg compared to the non-injured leg. Females demonstrated a decrease in peak knee flexion (p = 0.011) and knee flexion RoM (p = 0.023) in the injured leg compared to the non-injured leg. Average LSI scores were 92.4% for males and 94.5% for females.

CONCLUSIONS

Although LSI scores were > 90%, clinical relevant altered movement patterns were detected in the injured leg compared to the non-injured leg. Caution is warranted to solely rely on LSI scores to determine RTS readiness.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION

The University of Groningen, ID 2012.362.

LEVEL OF EVIDENCE

III.

Clinical Outcomes After Combined Anterior Cruciate Ligament and Anterolateral Ligament Reconstruction

Background

Graft rupture rate, return to sport and persistent rotational instability remain a concern postoperatively following anterior cruciate ligament (ACL) reconstruction. The anterolateral ligament (ALL) has recently been shown to act as a lateral knee stabilizer that helps improve rotational stability. To improve functional and clinical outcomes, a combined ACL reconstruction with an associated ALL reconstruction has been proposed.

Purpose

The main purpose of this study was to evaluate the clinical outcomes of the combined ACL and ALL reconstruction.

Methods

A literature search in PubMed was performed and papers reporting on clinical outcomes after combined ACL and ALL reconstruction were identified. The inclusion criteria was a minimum 2-year follow-up.

Results

Five studies were included in the review. The overall graft failure rate in patients with ACL and ALL reconstruction was <3% at 2 years minimum after surgery. Comparison analysis in a high-risk population demonstrated that the graft failure rate in combined ACL and ALL reconstruction was 2.5 times lower than with isolated bone-patella tendon-bone graft and 3.1 times lower than with isolated hamstring graft. The medial meniscal repair failure rate was also 2 times lower in the combined ACL and ALL reconstruction group compared with isolated ACL reconstruction. Return to sport and functional outcomes did not show any significant difference between the groups. The rate of reoperations was not increased in patients with combined ACL and ALL reconstruction.

Conclusions

Overall, combined ACL and ALL reconstruction provides promising results that may improve graft rupture rates and meniscal repair failure rates, while maintaining excellent functional outcomes.

Short-term complications in intra- and extra-articular anterior cruciate ligament reconstruction. Comparison with the literature on isolated intra-articular reconstruction. A multicenter study by the French Arthroscopy Society

INTRODUCTION

Lateral tenodesis (LT) is performed to limit the risk of iterative tear following anterior cruciate ligament (ACL) reconstruction in at-risk patients. By adding an extra procedure to isolated ACL graft, LT reconstruction increases operating time and may complicate postoperative course. The objective of the present study was to evaluate the rate of early complications. The study hypothesis was that associating ALL reconstruction to ACL reconstruction does not increase the complications rate found with isolated ACL reconstruction.

MATERIAL AND METHODS

A prospective multicenter study included 392 patients: 70% male; mean age, 29.9 years; treated by associated ACL and LT reconstruction. All adverse events were inventoried.

RESULTS

Mean hospital stay was 2 days, with 46% day-surgery. Walking was resumed at a mean 27 days, with an advantage for patients treated by the hamstring technique. The early postoperative complications rate was 12%, with 1.7% specifically implicating LT reconstruction: pain, hematoma, stiffness in flexion and extension, and infection. There was a 5% rate of surgical revision during the first year, predominantly comprising arthrolysis for extension deficit. The 1-year recurrence rate was 2.8%.

DISCUSSION

The complications rate for combined intra- and extra-articular reconstruction was no higher than for isolated intra-articular ACL reconstruction, with no increase in infection or stiffness rates. The rate of complications specific to ALL reconstruction was low, at 1.7%, and mainly involved fixation error causing lateral soft-tissue impingement.

LEVEL OF EVIDENCE

IV, prospective multicenter study.

Geometric Characteristics of the Knee Are Associated With a Noncontact ACL Injury to the Contralateral Knee After Unilateral ACL Injury in Young Female Athletes

BACKGROUND

Contralateral anterior cruciate ligament (CACL) injury after recovery from a first-time ACL rupture occurs at a high rate in young females; however, little is known about the risk factors associated with bilateral ACL trauma.

HYPOTHESIS

The geometric characteristics of the contralateral knee at the time of the initial ACL injury are associated with risk of suffering a CACL injury in these female athletes.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Sixty-two female athletes who suffered their first noncontact ACL injury while participating in sports at the high school or college level were identified, and geometry of the femoral notch, ACL, tibial spines, tibial subchondral bone, articular cartilage surfaces, and menisci of the contralateral, uninjured, knee was characterized in 3 dimensions. We were unable to contact 7 subjects and followed the remaining 55 until either a CACL injury or an ACL graft injury occurred or, if they were not injured, until the date of last contact (mean, 34 months after their first ACL injury). Cox regression was used to identify risk factors for CACL injury.

RESULTS

Ten (18.2%) females suffered a CACL injury. Decreases of 1 SD in femoral intercondylar notch width (measured at its outlet and anterior attachment of the ACL) were associated with increases in the risk of suffering a CACL injury (hazard ratio = 1.88 and 2.05, respectively). Likewise, 1 SD decreases in medial-lateral width of the lateral tibial spine, height of the medial tibial spine, and thickness of the articular cartilage located at the posterior region of the medial tibial compartment were associated with 3.59-, 1.75-, and 2.15-fold increases in the risk of CACL injury, respectively.

CONCLUSION

After ACL injury, subsequent injury to the CACL is influenced by geometry of the structures that surround the ACL (the femoral notch and tibial spines). This information can be used to identify individuals at increased risk for CACL trauma, who might benefit from targeted risk-reduction interventions.

Preoperative Short Form Health Survey Score Is Predictive of Return to Play and Minimal Clinically Important Difference at a Minimum 2-Year Follow-up After Anterior Cruciate Ligament Reconstruction

BACKGROUND

There is increased interest in understanding the preoperative determinants of postoperative outcomes. Return to play (RTP) and the patient-reported minimal clinically important difference (MCID) are useful measures of postoperative outcomes after anterior cruciate ligament reconstruction (ACLR).

PURPOSE

To define the MCID after ACLR and to investigate the role of preoperative outcome scores for predicting the MCID and RTP after ACLR.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

There were 294 active athletes enrolled as part of an institutional ACL registry with a minimum 2-year follow-up who were eligible for inclusion. A questionnaire was administered to elicit factors associated with RTP. Patient demographic and clinical data as well as patient-reported outcome measures were captured as part of the registry. Outcome measures included the International Knee Documentation Committee (IKDC) subjective knee evaluation form, Lysholm scale, and 12-Item Short Form Health Survey (SF-12) physical component summary (PCS) and mental component summary (MCS). Preoperative outcome score thresholds predictive of RTP were determined using a receiver operating characteristic (ROC) with area under the curve (AUC) analysis. The MCID was calculated using a distribution-based method. Multivariable logistic models were fitted to identify predictors for achieving the MCID and RTP.

RESULTS

At a mean (±SD) follow-up of 3.7 ± 0.7 years, 231 patients were included from a total 294 eligible patients. The mean age and body mass index were 26.7 ± 12.5 years and 23.7 ± 3.2 kg/m², respectively. Of the 231 patients, 201 (87.0%) returned to play at a mean time of 10.1 months. Two-year postoperative scores on all measures were significantly increased from preoperative scores (IKDC: 50.1 ± 15.6 to 87.4 ± 10.7; Lysholm: 61.2 ± 18.1 to 89.5 ± 10.4; SF-12 PCS: 41.5 ± 9.0 to 54.7 ± 4.6; SF-12 MCS: 53.6 ± 8.1 to 55.7 ± 5.7; P < .001 for all). The corresponding MCID values were 9.0 (IKDC), 10.0 (Lysholm), 5.1 (SF-12 PCS), and 4.3 (SF-12 MCS). Preoperative score thresholds predictive of RTP were the following: IKDC, 60.9; Lysholm, 57.0; SF-12 PCS, 42.3; and SF-12 MCS, 48.3. These thresholds were not independently predictive but achieved significance as part of the multivariable analysis. In the multivariable analysis for RTP, preoperative SF-12 PCS scores above 42.3 (odds ratio [OR], 2.73; 95% CI, 1.09-7.62) and SF-12 MCS scores above 48.3 (OR, 4.41; 95% CI, 1.80-10.98) were predictive for achieving RTP; an ACL allograft (OR, 0.26; 95% CI, 0.06-1.00) was negatively predictive of RTP. In the multivariable analysis for the MCID, patients with higher preoperative scores were less likely to achieve the MCID ( P < .0001); however, a higher preoperative SF-12 MCS score was predictive of achieving the MCID on the IKDC form (OR, 1.27; 95% CI, 1.11-1.52) and Lysholm scale (OR, 1.08; 95% CI, 1.00-1.16). Medial meniscal injuries, older age, and white race were also associated with a decreased likelihood for achieving the MCID.

CONCLUSION

Preoperative SF-12 MCS and PCS scores were predictive of RTP after ACLR; patients scoring above 42.3 on the SF-12 PCS and 48.3 on the SF-12 MCS were more likely to achieve RTP. Additionally, we defined the MCID after ACLR and found that higher SF-12 MCS scores were predictive of achieving the MCID on knee-specific questionnaires.

Thirty-Year Experience With ACL Reconstruction Using Patellar Tendon: A Critical Evaluation of Revision and Reoperation

Background:

During the preoperative discussion prior to anterior cruciate ligament reconstruction (ACLR), patients are often interested in data regarding rates of revision reconstruction, reoperation, concomitant pathologic changes, and future contralateral ACL injury.

Purpose:

To analyze a single surgeon’s experience with primary and revision ACLR over a 30-year interval, focusing on incidence and risk factors for revision and reoperation.

Study Design:

Case series; Level of evidence, 4.

Methods:

Patients who underwent ACLR from 1986 to 2016 were identified from a prospectively maintained database. Covariates of interest included age, sex, time, and graft selection. Outcomes of interest included revision and reoperation rates.

Results:

A total of 2450 ACLRs (mean patient age, 29 years; 58% male) were reviewed. Among primary ACLRs performed (n = 2225), 68% entailed bone–patellar tendon–bone (BTB) autograft and 30% entailed BTB allograft. Patients undergoing ACLR with autograft and allograft had a mean age of 22 and 37 years, respectively. The rate of revision ACLR was 1.8% and 3.5% for primary and revision cases, respectively. An increased rate of revision was noted among females compared with males (2.6% vs 1.2%) and among allografts compared with autografts (2.7% vs 1.3%). Low-dose irradiation did not affect allograft revision rates. The nonrevision reoperation rate following primary ACLR was 12%. The nonrevision reoperation rate was lower among primary cases reconstructed with allograft than autograft (9% vs 13%). Seventeen percent of cases involved concomitant meniscal repair and, among these, 13% required revision meniscal surgery. The rate of contralateral ACLR was 5.3%

Conclusion:

This information is useful in the informed consent process, for perioperative decision making regarding graft choice, and for identifying patients who are at risk for injuring the uninvolved knee.

Outcomes of ACL Reconstruction in Patients with Diabetes

PURPOSE

Diabetes has been associated with adverse outcomes after various types of surgery. There are no previously published data regarding the effect of diabetes on outcomes from anterior cruciate ligament reconstruction (ACLR). The purpose of this study was to test the hypotheses that diabetes is associated with worse clinical outcomes and a higher prevalence of subsequent surgeries after ACLR.

METHODS

Anterior cruciate ligament-deficient patients (n = 2198) undergoing unilateral ACLR from a multicenter prospective study were included. Patients who self-reported diabetes on the basis of comorbidity questions before surgery were identified from the database. They were compared with the remainder of the cohort who did not self-report diabetes. All patients were followed up for a minimum of 2 yr after their index surgery. A minimum 2-yr follow-up was attained on 1905/2198 (87%) via completed outcome questionnaires and 2096/2198 (95%) regarding subsequent surgery. The primary outcome measures were three validated outcome instruments. The secondary outcome measure was the incidence of additional surgery on the ipsilateral and contralateral knees.

RESULTS

Patients with diabetes had a significantly higher activity level at 2 yr (OR = 2.96; 95% CI, 1.30-6.77; P = 0.01), but otherwise slightly worse clinical outcomes, compared with patients without diabetes (OR range = 0.42-0.59). The prevalence of subsequent surgeries in patients with diabetes was not significantly different from the prevalence in patients without diabetes.

CONCLUSIONS

Patients with diabetes maintain a higher activity level after ACLR despite slightly lower patient-reported outcome scores compared with patients without diabetes and do not have a higher rate of subsequent surgery.

Update on Anterior Cruciate Ligament Rupture and Care in the Female Athlete

As female athlete sports participation has continued to increase, the rate of anterior cruciate ligament (ACL) rupture in female athletes has also increased. Individualized, patient-specific treatment is crucial to achieving optimal outcomes; ACL reconstruction must accurately restore native ACL anatomy and address any concomitant injury to secondary stabilizers. Rehabilitation programs should target hip, core, and trunk neuromuscular control; allow adequate time for graft ligamentization; and address the psychosocial needs of the athlete.

Return to play and performance after anterior cruciate ligament reconstruction in the National Basketball Association: surgeon case series and literature review

OBJECTIVES

To investigate return to play (RTP) and functional performance after anterior cruciate ligament reconstruction (ACLR) in National Basketball Association (NBA) players and to perform a systematic review of the literature to understand RTP after ACLR in professional basketball.

METHODS

NBA players undergoing ACLR between 2008 and 2014 by two surgeons were identified. RTP and performance were assessed based on a review of publically available statistics. A systematic review of the literature was performed using the MEDLINE database. Inclusion criteria were: English language, ACL surgery outcome, professional basketball and RTP outcome. We reviewed studies for RTP rates and RTP performance.

RESULTS

Our study included 12 professional basketball players with NBA level experience. Eleven of the 12 players returned to their prior level of play. Eight of the 9 (88.9%) players actively playing in the NBA returned to play in the NBA at a mean 9.8 months. Among players returning to NBA play, during RTP season 1, mean per game statistics decreased for the following: minutes, points, rebounds, assists, steals, blocks, turnovers and personal fouls - none of these changes reached statistical significance. Player efficiency ratings significantly declined from pre-injury (12.5) to the first RTP season (7.6) (p = 0.05). By RTP season 2, player performance metrics approximated pre-injury levels and were not significantly different. Six studies met inclusion criteria; reported RTP rates ranged from 78-86%. Identified studies similarly found a decline in functional performance after RTP.

CONCLUSION

There is a high rate (89%) of return to NBA play for NBA players undergoing ACLR. After RTP, however, there is a quantitative decline in initial season 1 RTP statistics with a significant decrease in player efficiency rating. By RTP season 2, performance metrics demonstrated an improvement compared to RTP season 1 but did not reach pre-injury functional performance, though performance metrics are not significantly different between pre-injury and RTP season 2.

Subsequent Surgery After Revision Anterior Cruciate Ligament Reconstruction: Rates and Risk Factors From a Multicenter Cohort

BACKGROUND

While revision anterior cruciate ligament reconstruction (ACLR) can be performed to restore knee stability and improve patient activity levels, outcomes after this surgery are reported to be inferior to those after primary ACLR. Further reoperations after revision ACLR can have an even more profound effect on patient satisfaction and outcomes. However, there is a current lack of information regarding the rate and risk factors for subsequent surgery after revision ACLR.

PURPOSE

To report the rate of reoperations, procedures performed, and risk factors for a reoperation 2 years after revision ACLR.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

A total of 1205 patients who underwent revision ACLR were enrolled in the Multicenter ACL Revision Study (MARS) between 2006 and 2011, composing the prospective cohort. Two-year questionnaire follow-up was obtained for 989 patients (82%), while telephone follow-up was obtained for 1112 patients (92%). If a patient reported having undergone subsequent surgery, operative reports detailing the subsequent procedure(s) were obtained and categorized. Multivariate regression analysis was performed to determine independent risk factors for a reoperation.

RESULTS

Of the 1112 patients included in the analysis, 122 patients (11%) underwent a total of 172 subsequent procedures on the ipsilateral knee at 2-year follow-up. Of the reoperations, 27% were meniscal procedures (69% meniscectomy, 26% repair), 19% were subsequent revision ACLR, 17% were cartilage procedures (61% chondroplasty, 17% microfracture, 13% mosaicplasty), 11% were hardware removal, and 9% were procedures for arthrofibrosis. Multivariate analysis revealed that patients aged <20 years had twice the odds of patients aged 20 to 29 years to undergo a reoperation. The use of an allograft at the time of revision ACLR (odds ratio [OR], 1.79; P = .007) was a significant predictor for reoperations at 2 years, while staged revision (bone grafting of tunnels before revision ACLR) (OR, 1.93; P = .052) did not reach significance. Patients with grade 4 cartilage damage seen during revision ACLR were 78% less likely to undergo subsequent operations within 2 years. Sex, body mass index, smoking history, Marx activity score, technique for femoral tunnel placement, and meniscal tearing or meniscal treatment at the time of revision ACLR showed no significant effect on the reoperation rate.

CONCLUSION

There was a significant reoperation rate after revision ACLR at 2 years (11%), with meniscal procedures most commonly involved. Independent risk factors for subsequent surgery on the ipsilateral knee included age <20 years and the use of allograft tissue at the time of revision ACLR.

Anterolateral Ligament Reconstruction Is Associated With Significantly Reduced ACL Graft Rupture Rates at a Minimum Follow-up of 2 Years: A Prospective Comparative Study of 502 Patients From the SANTI Study Group

BACKGROUND

Graft failure and low rates of return to sport are major concerns after anterior cruciate ligament (ACL) reconstruction, particularly in a population at risk.

PURPOSE

To evaluate the association between reconstruction techniques and subsequent graft rupture and return-to-sport rates in patients aged 16 to 30 years participating in pivoting sports.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

A prospective study of patients undergoing primary ACL reconstruction with a bone-patellar tendon-bone (B-PT-B) graft, quadrupled hamstring tendon (4HT) graft, or hamstring tendon graft combined with anterolateral ligament reconstruction (HT+ALL) was conducted by the Scientific ACL NeTwork International (SANTI) Study Group. Survivorship data from Kaplan-Meier analysis were analyzed in multivariate Cox regression models to identify the prognosticators of graft ruptures and return to sport.

RESULTS

Five hundred two patients (mean age, 22.4 ± 4.0 years) with a mean follow-up of 38.4 ± 8.5 months (range, 24-54 months) were included. There were 105 B-PT-B, 176 4HT, and 221 HT+ALL grafts. The mean postoperative scores at latest follow-up were the following: Lysholm: 92.4 ± 8.6, Tegner: 7.4 ± 2.1, and subjective International Knee Documentation Committee (IKDC): 86.8 ± 10.5 for B-PT-B grafts; Lysholm: 91.3 ± 9.9, Tegner: 6.6 ± 1.8, and subjective IKDC: 85.4 ± 10.4 for 4HT grafts; and Lysholm: 91.9 ± 10.2, Tegner: 7.0 ± 2.0, and subjective IKDC: 81.8 ± 13.1 for HT+ALL grafts. The mean side-to-side laxity was 0.6 ± 0.9 mm for B-PT-B grafts, 0.6 ± 1.0 mm for 4HT grafts, and 0.5 ± 0.8 mm for HT+ALL grafts. At a mean follow-up of 38.4 months, the graft rupture rates were 10.77% (range, 6.60%-17.32%) for 4HT grafts, 16.77% (range, 9.99%-27.40%) for B-PT-B grafts, and 4.13% (range, 2.17%-7.80%) for HT+ALL grafts. The rate of graft failure with HT+ALL grafts was 2.5 times less than with B-PT-B grafts (hazard ratio [HR], 0.393; 95% CI, 0.153-0.953) and 3.1 times less than with 4HT grafts (HR, 0.327; 95% CI, 0.130-0.758). There was no significant difference in the graft failure rate between 4HT and B-PT-B grafts (HR, 1.204; 95% CI, 0.555-2.663). Other prognosticators of graft failure included age ≤25 years ( P = .012) and a preoperative side-to-side laxity >7 mm ( P = .018). The HT+ALL graft was associated with higher odds of returning to preinjury levels of sport than the 4HT graft (odds ratio [OR], 1.938; 95% CI, 1.174-3.224) but not compared with the B-PT-B graft (OR, 1.460; 95% CI, 0.813-2.613).

CONCLUSION

In a high-risk population of young patients participating in pivoting sports, the rate of graft failure with HT+ALL grafts was 2.5 times less than with B-PT-B grafts and 3.1 times less than with 4HT grafts. The HT+ALL graft is also associated with greater odds of returning to preinjury levels of sport when compared with the 4HT graft.

THE ASSOCIATIONS BETWEEN HIP STRENGTH AND HIP KINEMATICS DURING A SINGLE LEG HOP IN RECREATIONAL ATHLETES POST ACL RECONSTRUCTION COMPARED TO HEALTHY CONTROLS

BACKGROUND

Only a small amount of evidence exists linking hip abductor weakness to dynamic knee valgus during static and dynamic activities. The associations of hip extensor strength and hip kinematics during the landing of a single leg hop are not known. Purpose: To determine if relationships exist between hip extensor and abductor strength and hip kinematics in both involved and uninvolved limb during the landing phase of a single leg hop in recreational athletes post anterior cruciate ligament (ACL) reconstruction. The presence of similar associations was also evaluated in healthy recreational athletes.

STUDY DESIGN

Controlled Laboratory Study; Cross-sectional.

METHODS

Twenty-four recreational college-aged athletes participated in the study (12 post ACL reconstruction; 12 healthy controls). Sagittal and frontal plane hip kinematic data were collected for five trials during the landing of a single leg hop. Hip extensor and abductor isometric force production was measured using a hand-held dynamometer and normalized to participants' height and weight. Dependent and independent t-tests were used to analyze for any potential differences in hip strength or kinematics within and between groups, respectively. Pearson's r was used to demonstrate potential associations between hip strength and hip kinematics for both limbs in the ACL group and the right limb in the healthy control group.

RESULTS

Independent t-tests revealed that participants post ACL reconstruction exhibited less hip extensor strength (0.18 N/Ht*BW vs. 0.25 N/Ht*BW, p=<.01) and landed with greater hip adduction (9.0 º vs. 0.8 º, p=<.01) compared with their healthy counterparts. In the ACL group, Pearson's r demonstrated a moderate and indirect relationship (r=-.62, p=.03) between hip extensor strength and maximum hip abduction/adduction angle in the involved limb. A moderate and direct relationship between hip abductor strength and maximum hip flexion angle was demonstrated in the both the involved (r=.62) and uninvolved limb (r=.65, p=.02). No significant associations were demonstrated between hip extensor or abductor strength and hip flexion and/or abduction/adduction angles in the healthy group.

CONCLUSION

The results suggest that hip extensors may play a role in minimizing hip adduction in the involved limb while the hip abductors seem to play a role in facilitating hip flexion during the landing phase of a single leg hop for both limbs following ACL reconstruction. Researchers and clinicians alike should consider the importance of the hip extensors in playing a more prominent role in contributing to frontal plane motion.

LEVELS OF EVIDENCE

Level 2a.

Return to Play and Patient Satisfaction After ACL Reconstruction: Study with Minimum 2-Year Follow-up

BACKGROUND

Return to play and patient satisfaction after anterior cruciate ligament reconstruction (ACLR) have been inconsistently studied. The purposes of this study were to (1) investigate rates and predictors of return to play after ACLR, (2) evaluate patient satisfaction after ACLR, and (3) analyze the relationship between return to play and satisfaction with the result of ACLR.

METHODS

Eligible patients were active athletes included in an institutional ACL registry who had undergone ACLR and had been followed for a minimum of 2 years. A questionnaire was administered to elicit information regarding factors associated with return to play, sports performance, reinjury, and overall patient satisfaction. The Wilcoxon-Mann-Whitney U test was used to compare return to play with patient satisfaction. Multivariable logistic regression was used to identify demographic, sports, and clinical factors associated with return to play.

RESULTS

Two hundred and thirty-two patients with a mean age of 26.7 years (standard deviation [SD] = 12.5 years) who had been followed for a mean of 3.7 years were enrolled. Of 231 patients who responded to the return-to-play question, 201 (87.0%) had returned to play, at a mean of 10.1 months; of 175 athletes eligible to return to their prior level of competition, 89.1% had done so. Overall satisfaction was high: 85.4% were very satisfied with the outcome and 98.1% stated that they would have surgery again. Patients were more likely to respond "very satisfied" if they had returned to play (p < 0.001). Use of a patellar tendon autograft (odds ratio [OR] = 5.63, 95% confidence interval [CI] = 1.32 to 25.76) increased the chance of returning to play whereas playing soccer (OR = 0.23, 95% CI = 0.08 to 0.66) or lacrosse (OR = 0.24, 95% CI = 0.06 to 0.99) preoperatively decreased the likelihood of returning to play.

CONCLUSIONS

The rates of return to play and patient satisfaction are high after ACLR in active athletes. The use of patellar tendon autograft increased the likelihood of returning to play whereas preinjury participation in soccer and lacrosse decreased these odds. Additionally, patients who returned to play were more likely to be very satisfied with the result of the ACLR.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Return to sport: Does excellent 6-month strength and function following ACL reconstruction predict midterm outcomes?

PURPOSE

The purpose of this study was to determine whether patients with excellent 6-month functional testing after ACL reconstruction had (1) higher risk of subsequent ACL tears, (2) superior knee function, and (3) increased activity levels compared to those with delayed clearance for return to sports at midterm follow-up.

METHODS

A total of 223 patients underwent primary ACL reconstruction by a single surgeon and had functional and isokinetic testing performed 6 months post-operatively between 1998 and 2005. Of the 223 patients, 52 (23 %) made the excellent group and were allowed return to sport at 6 months, and the remaining 171 (77 %) constituted the delayed group. Rate of ACL graft tear and native contralateral ACL tear was compared between groups. In addition, IKDC and Tegner scores were compared at a mean 4-year follow-up.

RESULTS

The graft rupture rate was similar in the excellent group (3.8 %, n = 2) compared to the delayed group (4.7 %, n = 8; p = 0.30). However, there was a higher rate of contralateral ACL tear in the excellent group (15.4 %, n = 8 vs. 5.3 %, n = 9; p = 0.003). The excellent 6-month group had superior IKDC scores (94.3 ± 6.4 vs. 90.9 ± 9.7; p = 0.04) and Tegner scores (6.6 ± 1.8 vs. 5.7 ± 1.6; p = 0.01).

CONCLUSION

Patients with an excellent performance on their isokinetic strength and functional testing at 6 months after ACL reconstruction have superior knee function and higher activity levels at midterm follow-up. However, these patients appear to be at greater risk of contralateral ACL injury, which may be related to their increased activity level. When isokinetic and functional testing is used for return-to-sport decisions, physicians should caution patients about the risk of contralateral ACL injury for high performing patients.

LEVEL OF EVIDENCE

Retrospective Review with Control, Level III.

Traumatic graft rupture after primary and revision anterior cruciate ligament reconstruction: retrospective analysis of incidence and risk factors in 2915 cases

PURPOSE

To determine incidence and risk factors for traumatic graft rupture following primary and revision anterior cruciate ligament (ACL) reconstruction.

METHODS

All cases of isolated ACL reconstructions (primary or revision) performed at our institution between January 2007 and December 2010 were included. From this group of 2467 primary reconstructions (32.4 ± 12.2 years) and 448 revision reconstructions (33.0 ± 10.4 years), we identified all patients who underwent revision ACL reconstruction following traumatic graft rupture in further course and all patients who underwent contralateral primary ACL reconstruction until January 2014. Age, gender, time from index procedure and graft diameter (for hamstring autografts) were analysed in terms of being a potential risk factor for graft rupture.

RESULTS

Within a follow-up period of 5.0 ± 1.1 years (3.0-7.0), a total of 82 traumatic graft ruptures were identified, resulting in an incidence of 2.8 %. Seventy-three cases were seen following primary reconstructions (3.0 %), and nine cases following revision reconstructions (2.0 %), respectively (n.s.). Age younger than 25 years was identified as a risk factor for both groups (p = 0.001 and p = 0.008; odds ratio 6.0 and 6.4, respectively). In primary reconstruction, male patients had a higher risk of graft rupture compared with females (3.7 vs. 1.6 %; p = 0.005), and the first year after index procedure was associated with a higher risk of graft rupture compared with the following (p < 0.001). Graft diameter did not influence the risk of graft rupture. Incidence of contralateral ACL rupture was 3.1 %, which was not different to the incidence of graft rupture ipsilaterally (n.s.).

CONCLUSION

No statistically significant differences were seen between graft rupture incidence of primary and revision ACL reconstructions. Young age (<25 years) and short time to the index procedure (especially within the first year) were confirmed as risk factors for graft rupture in both groups. Male gender was a risk factor for primary reconstructions. Graft diameter had no influence on graft rupture rates. No difference in incidence of graft rupture compared to ACL rupture on the contralateral side was apparent.

LEVEL OF EVIDENCE

Retrospective case series, Level IV.

Functional performance 2-9 years after ACL reconstruction: cross-sectional comparison between athletes with bone-patellar tendon-bone, semitendinosus/gracilis and healthy controls

PURPOSE

The purpose of this cross-sectional study was to provide descriptive data on functional performance in men and women with ACLR, to compare bone-patellar tendon-bone (BPTB) with semitendinosus/gracilis (STG) within the same sex and to compare the ACLR subjects with healthy controls.

METHODS

Eligible participants comprised 100 men (43 % BPTB) and 84 women (41 % BPTB) after ACLR, of whom 30 men (STG n = 19; BPTB n = 11) and 18 women (STG n = 12; BPTB n = 6) were untraceable/not willing and 15 men (STG n = 9; BPTB n = 6) and 18 women (STG n = 12; BPTB n = 3) were not able to take part in the measurements because of injury. Besides men BPTB (n = 24), men STG (n = 27), women BPTB (n = 23) and women STG (n = 23), healthy men (n = 22) and women (n = 22) participated. Measurements consisted of questionnaires, isokinetic peak torque and endurance tests, a hop test battery and drop jump including video analysis.

RESULTS

Only the occurrence of dynamic knee valgus differed between ACLR and healthy subjects.

CONCLUSION

Two to nine years after ACLR, 16 % of athletes could not participate because of a lower extremity injury. In the remaining group, this study showed similar results for males and females with BPTB compared with STG. Also, similar results are found for quantity of movement comparing operated and healthy subjects. For quality of movement, only the occurrence of dynamic knee valgus in landing from a jump is higher in operated subjects compared with healthy controls. This supports the relevance of a focus on quality of movement as part of ACLR rehabilitation programmes and return to sports criteria.

LEVEL OF EVIDENCE

III.

Genome-wide association analysis in dogs implicates 99 loci as risk variants for anterior cruciate ligament rupture

Anterior cruciate ligament (ACL) rupture is a common condition that can be devastating and life changing, particularly in young adults. A non-contact mechanism is typical. Second ACL ruptures through rupture of the contralateral ACL or rupture of a graft repair is also common. Risk of rupture is increased in females. ACL rupture is also common in dogs. Disease prevalence exceeds 5% in several dog breeds, ~100 fold higher than human beings. We provide insight into the genetic etiology of ACL rupture by genome-wide association study (GWAS) in a high-risk breed using 98 case and 139 control Labrador Retrievers. We identified 129 single nucleotide polymorphisms (SNPs) within 99 risk loci. Associated loci (P<5E-04) explained approximately half of phenotypic variance in the ACL rupture trait. Two of these loci were located in uncharacterized or non-coding regions of the genome. A chromosome 24 locus containing nine genes with diverse functions met genome-wide significance (P = 3.63E-0.6). GWAS pathways were enriched for c-type lectins, a gene set that includes aggrecan, a gene set encoding antimicrobial proteins, and a gene set encoding membrane transport proteins with a variety of physiological functions. Genotypic risk estimated for each dog based on the risk contributed by each GWAS locus showed clear separation of ACL rupture cases and controls. Power analysis of the GWAS data set estimated that ~172 loci explain the genetic contribution to ACL rupture in the Labrador Retriever. Heritability was estimated at 0.48. We conclude ACL rupture is a moderately heritable highly polygenic complex trait. Our results implicate c-type lectin pathways in ACL homeostasis.

Return to Play After Revision Anterior Cruciate Ligament Reconstruction in National Football League Players

Background:

National Football League (NFL) players who undergo anterior cruciate ligament (ACL) reconstruction have been shown to have a lower return to play (RTP) than previously expected. However, RTP in the NFL after revision ACL reconstruction (RACLR) is not well defined.

Purpose/Hypothesis:

The purpose of this study is to determine the RTP of NFL players after RACLR and evaluate factors that predict RTP. Our hypothesis was that more experienced and established players would be more likely to RTP after RACLR.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A total of 24 NFL players who underwent RACLR between 2007 and 2014 were reviewed and evaluated. Return to NFL play, time to return, seasons and games played prior to and after revision surgery, draft status, and demographic data were collected. Overall RTP was determined, and players who did RTP were compared with those unable to RTP. Data were also compared with control players matched for age, position, size, and experience.

Results:

After RACLR, 79% (19/24) of NFL players returned to NFL regular-season play at an average of 12.6 months. All players who were drafted in the first 4 rounds, played in at least 55 games, or played 4 seasons of NFL play prior to injury were able to RTP. Players drafted in the first 4 rounds of the NFL draft were more likely to RTP than those who were not (odds ratio, 0.1; 95% CI, 0.01-1.00; P = .05). Those who returned to NFL play played in significantly less games and seasons after their injury than before (P = .01 and P = .01, respectively). However, these values did not differ when compared with matched controls (P = .67 and P = .33).

Conclusion:

NFL players who RTP after RACLR do so at a similar rate but prolonged time period compared with after primary ACL reconstruction. Athletes who were drafted in earlier rounds were more likely to RTP than those who were not. Additionally, player experience prior to injury is an important factor when predicting RTP after RACLR.

Editorial Commentary: Studying the Anterolateral Ligament of the Knee-Have We Lost Track of Our Main Focus?

Considerable recent debate has led to a greater understanding of the potential role of the anterolateral structures of the knee in improving the outcomes of anterior cruciate ligament reconstruction. Although cadaveric studies have made a very important contribution to our understanding of anatomy, their weakness lies in a difficulty in knowing whether extrapolating biomechanical findings from a laboratory study to the clinical scenario can be valid.

An Ecological Study of Anterior Cruciate Ligament Reconstruction, Part 2: Functional Performance Tests Correlate With Return-to-Sport Outcomes

Background:

Additional high-quality prospective studies are needed to better define the objective criteria used in relation to return-to-sport decisions after anterior cruciate ligament (ACL) reconstruction in active populations.

Purpose:

To investigate prospectively the relationship between functional performance test results at 24 weeks postoperative and return-to-sport activity (Tegner activity score) at 12 and 24 months, respectively, after synthetic (ligament advanced reinforcement system [LARS]) and autograft (doubled semitendinosus/gracilis [2ST/2GR]) ACL reconstructions.

Study Design:

Case series; Level of evidence, 4.

Methods:

A total of 64 patients who underwent ACL reconstruction (32 LARS, 32 2ST/2GR autograft; mean age, 27.9 years; body mass index [BMI], 24.9 kg/m²) were assessed preoperatively and at staged intervals postoperatively up to 24 weeks for isokinetic testing of quadriceps and hamstring average power per repetition at 60 deg/s and 180 deg/s, a battery of hop tests, peak vertical ground-reaction force (vGRF), and time to peak vGRF (in seconds) during a step- and jump-down task onto a force platform and peak speed (m/s) using a global positioning system (GPS unit) during a running task. A cohort of 32 healthy matched participants (mean age, 26.31 years; BMI, 25.7 kg/m²) were also tested to act as reference. Pearson correlation was calculated to assess correlation of each performance measure at 24 weeks postoperative with activity outcomes (Tegner score) at 12 and 24 months.

Results:

The strongest correlation between physical performance tests and return-to-sport outcomes was observed with peak speed during running. Large correlations were also observed for hamstring isokinetic power and hop test for distance. Moderate correlations were observed for timed hop, peak vGRF during a jump-down task, and quadriceps isokinetic power. No statistical correlations were observed for time to peak vGRF during a step-down and jump-down task as well as peak vGRF during a step-down task. When the performance tests were pooled together, mean postoperative improvements of 24% were observed from preoperative to 24 weeks within the surgical cohort. For each performance test, preoperative level of function strongly correlated with performance levels on the same test at 24 weeks.

Discussion:

The results of this study indicate that clinicians might seek to prioritize these tests and the rehabilitation themes they imply when seeking to maximize postoperative ACL activity outcomes. The observed strength between pre- and postoperative performance tests and return-to-sport outcomes within this study highlights the potential value of preoperative conditioning before undergoing ACL reconstruction. Future research should examine absolute predictive criterion thresholds for functional performance-based tests and reinjury risk reduction after ACL reconstruction.

Differences in the Dominant and Non-Dominant Knee Valgus Angle in Junior Elite and Amateur Soccer Players after Unilateral Landing

More than 70% of all knee injuries in soccer occur in non-contact situations. It is known that increased lower limb dynamic knee valgus is associated with such situations. Little has been found out about differences in knee kinematics of the dominant (kicking) and non-dominant (supporting) leg during a single leg landing. A total of 114 male adolescent soccer players (age 14.6 ± 1.1 years) from elite (N = 66) and amateur soccer clubs (N = 48) performed a single leg drop landing down from a box. For each leg, the two-dimensional dynamic knee valgus angle (DKVA) was calculated. Paired t-tests were used to statistically determine significant differences between dominant and non-dominant leg DKVA, and t-tests were calculated between the two performance groups. Statistically significant differences (p < 0.05) were identified for the DKVA between the dominant and non-dominant leg for both amateur and elite players, showing a greater DKVA for the dominant leg. Group differences for the DKVA between amateur and elite players were not found, neither for the dominant, nor for the non-dominant leg. It can be concluded that the non-dominant leg showed more stable dynamics than the dominant leg during unilateral landing regardless of the player’s performance level. This could be due to adaptions to sport-specific requirements. Therefore, it is recommended that programs to prevent knee injuries among soccer players consider the dynamics of each leg individually.

Technical Considerations in Revision Anterior Cruciate Ligament (ACL) Reconstruction for Operative Techniques in Orthopaedics

As the incidence of anterior cruciate ligament (ACL) reconstruction continues to increase, the rate of revision surgery continues to climb. Revision surgery has inherent challenges that must be addressed in order to achieve successful results. The cause of the primary ACL reconstruction failure should be determined, and careful preoperative planning should be performed to address the cause(s) of failure. Each patient undergoing revision surgery should undergo a thorough history and physical examination, receive full length alignment radiographs, lateral radiographs, 45-degree flexion weight-bearing postero-anterior radiographs, and patellofemoral radiographs. 3-dimensional computed topography (CT) scan should be performed to assess tunnel position and widening. Magnetic resonance imaging (MRI) should be used to assess for intra-articular soft tissue pathology. Meniscal tears, meniscal deficiency, anterolateral capsule injuries, bony morphology, age, activity level, connective tissue diseases, infection, graft choice, and tunnel position can all impact the success of ACL reconstruction surgery. Meniscal lesions should be repaired, and in cases of persistent rotatory instability, extra-articular procedures may be indicated. Furthermore, osteotomies may be needed to correct malalignment or excess posterior tibial slope. Depending on the placement and condition of the original femoral and tibial tunnels, revision surgery may be performed in a single procedure or in a staged manner. In most cases, the surgery can be performed in one procedure. Regardless, the surgeon must communicate with the patient openly regarding the implications of revision ACL surgery and the treatment plan should be developed in a shared fashion between the surgeon and the patient.

Biomechanical Effects of an Injury Prevention Program in Preadolescent Female Soccer Athletes

BACKGROUND

Anterior cruciate ligament (ACL) injuries are common, and children as young as 10 years of age exhibit movement patterns associated with an ACL injury risk. Prevention programs have been shown to reduce injury rates, but the mechanisms behind these programs are largely unknown. Few studies have investigated biomechanical changes after injury prevention programs in children. Purpose/Hypothesis: To investigate the effects of the F-MARC 11+ injury prevention warm-up program on changes to biomechanical risk factors for an ACL injury in preadolescent female soccer players. We hypothesized that the primary ACL injury risk factor of peak knee valgus moment would improve after training. In addition, we explored other kinematic and kinetic variables associated with ACL injuries.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 51 female athletes aged 10 to 12 years were recruited from soccer clubs and were placed into an intervention group (n = 28; mean [±SD] age, 11.8 ± 0.8 years) and a control group (n = 23; mean age, 11.2 ± 0.6 years). The intervention group participated in 15 in-season sessions of the F-MARC 11+ program (2 times/wk). Pre- and postseason motion capture data were collected during preplanned cutting, unanticipated cutting, double-leg jump, and single-leg jump tasks. Lower extremity joint angles and moments were estimated using OpenSim, a biomechanical modeling system.

RESULTS

Athletes in the intervention group reduced their peak knee valgus moment compared with the control group during the double-leg jump (mean [±standard error of the mean] pre- to posttest change, -0.57 ± 0.27 %BW×HT vs 0.25 ± 0.25 %BW×HT, respectively; P = .034). No significant differences in the change in peak knee valgus moment were found between the groups for any other activity; however, the intervention group displayed a significant pre- to posttest increase in peak knee valgus moment during unanticipated cutting ( P = .044). Additional analyses revealed an improvement in peak ankle eversion moment after training during preplanned cutting ( P = .015), unanticipated cutting ( P = .004), and the double-leg jump ( P = .016) compared with the control group. Other secondary risk factors did not significantly improve after training, although the peak knee valgus angle improved in the control group compared with the intervention group during unanticipated cutting ( P = .018).

CONCLUSION

The F-MARC 11+ program may be effective in improving some risk factors for an ACL injury during a double-leg jump in preadolescent athletes, most notably by reducing peak knee valgus moment.

CLINICAL RELEVANCE

This study provides motivation for enhancing injury prevention programs to produce improvement in other ACL risk factors, particularly during cutting and single-leg tasks.

Comparative Influence of Sport Type on Outcome After Anterior Cruciate Ligament Reconstruction at Minimum 2-Year Follow-up

PURPOSE

To investigate differences between sport types for patient-reported outcome after anterior cruciate ligament reconstruction (ACLR).

METHODS

Included patients were enrolled as part of a prospective institutional ACL registry. Inclusion criteria were preoperative self-identification as a competitive athlete, maximum score on the preoperative Marx Activity Scale, and minimum 2-year follow-up. Demographic, intraoperative, and outcome data were extracted from the registry. Outcome tools administered as part of the registry included International Knee Documentation Committee (IKDC), Lysholm-Tegner Scales, Marx Activity Scale (MAS), and 12-Item Short Form Health Survey (SF-12).

RESULTS

A total of 294 patients with a mean age of 25.5 years (standard deviation 12.1) met the study inclusion criteria; mean follow-up was 3.7 years. Included sports categories were soccer (n = 92; 31.3%), skiing (n = 67; 22.8%), basketball (n = 56; 19.1%), lacrosse (n = 38; 12.9%), football (n = 29; 9.9%), and Tennis (n = 12; 4.1%). At baseline, compared with other sports, lacrosse players have higher outcome scores while skiers had lower scores. At 2-year follow-up, however, across all outcome tools, football players demonstrated significantly higher outcome scores than all other athletes (IKDC, 93.2, P = .001; Lysholm, 93.2, P = .03; MAS, 13.1, P = .03; SF-12 Mental Component Summary, 57.9, P = .0002). Conversely, at 2-year follow-up, soccer players demonstrated a significantly lower Lysholm (86.7, P = .02) and a trend toward lower IKDC (85.6, P = .09) scores.

CONCLUSIONS

Patient-reported outcomes after ACLR among active athletes are comparable. Football players demonstrate quantitatively higher outcome scores whereas soccer players have lower scores. However, these outcome score differences may not be clinically significant and may be subject to confounding variables. Continued attention should be paid to understanding sport-specific outcome after ACLR.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Return to Play of Rugby Players After Anterior Cruciate Ligament Reconstruction Using Hamstring Autograft: Return to Sports and Graft Failure According to Age

PURPOSE

To assess return to play and the frequencies of graft failure in rugby players after anterior cruciate ligament (ACL) reconstruction using a hamstring autograft augmented with an artificial ligament and to compare outcomes between rugby players aged <20 and ≥20 years over the long term.

METHODS

A consecutive series of 146 rugby players who underwent ACL reconstruction with a hamstring autograft augmented with an artificial ligament were retrospectively reviewed. The study population was further divided into 2 groups aged <20 years and >20 years and compared.

RESULTS

Twenty-five patients could not be followed up, and 121 (83%) were evaluated. Most patients (90%, <20 years; 92%, ≥20 years) returned to play after ACL reconstruction. At an average follow-up period of 56.5 months, 16% of the patients sustained an ACL graft rupture. Regarding age, <20 years (n = 58, 48%) and ≥20 years (n = 63, 52%), younger players had a significantly higher failure rate (23% vs 5%, respectively; P = .006) and a shorter time to failure (22.8 ± 13.2 vs 35.4 ± 15.4 months, respectively; P = .006) than older players.

CONCLUSIONS

Rugby players were likely to return to play after ACL reconstruction with a hamstring autograft. However, there was a higher risk of graft failure in younger players than in older players. On the basis of this study, we conclude that the hamstring autograft may not be an appropriate graft source to use in a younger active population, including rugby players.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

How Are We Measuring Patient Satisfaction After Anterior Cruciate Ligament Reconstruction?

BACKGROUND

Reconstruction of the anterior cruciate ligament (ACL) is one of the most common orthopaedic operations in the United States. The long-term impact of ACL reconstruction is controversial, however, as longer term data have failed to demonstrate that ACL reconstruction helps alter the natural history of early onset osteoarthritis that occurs after ACL injury. There is significant interest in evaluating the value of ACL reconstruction surgeries.

PURPOSE

To examine the quality of patient satisfaction reporting after ACL reconstruction surgery.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic review of the MEDLINE database was performed using the PubMed interface. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines as well as the PRISMA checklist were employed. The initial search yielded 267 studies. The inclusion criteria were: English language, US patient population, clinical outcome study of ACL reconstruction surgery, and reporting of patient satisfaction included in the study. Study quality was assessed using the Newcastle-Ottawa scale.

RESULTS

A total of 22 studies met the inclusion criteria. These studies comprised a total of 1984 patients with a mean age of 31.9 years at the time of surgery and a mean follow-up period of 59.3 months. The majority of studies were evidence level 4 (n = 18; 81.8%), had a mean Newcastle-Ottawa scale score of 5.5, and were published before 2006 (n = 17; 77.3%); 5 studies (22.7%) failed to clearly describe their method for determining patient satisfaction. The most commonly used method for assessing satisfaction was a 0 to 10 satisfaction scale (n = 11; 50.0%). Among studies using a 0 to 10 scale, mean satisfaction ranged from 7.4 to 10.0. Patient-reported outcome and objective functional measures for ACL stability and knee function were positively correlated with patient satisfaction. Degenerative knee change was negatively correlated with satisfaction.

CONCLUSION

The level of evidence for studies reporting patient satisfaction is low, and the methodologies for reporting patient satisfaction are variable. Additionally, within the past decade there has been a significant decline in the inclusion of this outcome measure within published ACL studies. As sports surgeons are increasingly called on to demonstrate the value of operative procedures, attention should be paid to understanding and reporting patient satisfaction.

Return to prelesional Tegner level after anatomic anterior cruciate ligament reconstruction

INTRODUCTION

Injury and surgery of the anterior cruciate ligament (ACL) are very frequent within the sports environment. The purpose of the present study is to assess the level at which a group of athletes were able to return to play (RTP) after ACL reconstruction, and most importantly, the time for RTP.

MATERIALS AND METHODS

A prospective study with patients who presented an ACL injury and underwent ligament reconstruction surgery; a bone-tendon-bone reconstruction and a minimum follow-up of 24 months. The rates of RTP as well as correlations with IKDC and KT-1000 were collected.

RESULTS

42 patients were included (mean age 31.7 years old). Mean Tegner level was 6.7. 9.5 % of patients returned to sports 6 months after surgery, 52.3 % at 1 year, and 73.8 % at 2 years after ACL reconstruction. 11 patients did not achieve their preoperative Tegner level after 2 years of follow-up. Levels of KT-1000 of the operated side were normal, and IKDC levels reached 90 % of total.

CONCLUSIONS

Fear to a new injury, psychological factors, personality, type of life, and sports level previous to the injury are factors that influence when it comes to RTP after an ACL surgery. Level of evidence Level II descriptive analysis.

An Ecological Study of Anterior Cruciate Ligament Reconstruction, Part 1: Clinical Tests Do Not Correlate With Return-to-Sport Outcomes

BACKGROUND

Additional high-quality prospective studies are needed to better define the objective criteria used in relation to return-to-sport decisions after synthetic (ligament advanced reinforcement system [LARS]) and autograft (hamstring tendon [2ST/2GR]) anterior cruciate ligament (ACL) reconstruction in active populations.

PURPOSE

To prospectively investigate and describe the recovery of objective clinical outcomes after autograft (2ST/2GR) and synthetic (LARS) ACL reconstructions, as well as to investigate the relationship between these clinimetric test outcomes and return-to-sport activity (Tegner activity scale [TAS] score) at 12 and 24 months postoperatively.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 64 patients who underwent ACL reconstruction (32 LARS, 32 2ST/2GR autograft) and 32 healthy reference participants were assessed for joint laxity (KT-1000 arthrometer), clinical outcome (2000 International Knee Documentation Committee [IKDC] knee examination), and activity (TAS score) preoperatively and at 12, 16, 20, and 24 weeks and 12 and 24 months postoperatively.

RESULTS

There was no significant correlation observed between clinical results using the 2000 IKDC knee examination and TAS score at 24 months (r_s = 0.188, P = .137), nor were results for side-to-side difference (r_s = 0.030, P = .814) or absolute KT-1000 arthrometer laxity of the surgical leg at 24 months postoperatively (r_s = 0.076, P = .553) correlated with return-to-sport activity. Nonetheless, return-to-sport rates within the surgical cohort were 81% at 12 months and 83% at 24 months, respectively. No statistically significant differences were observed between physiological laxity of the uninjured knee within the surgical group compared with healthy knees within the reference group (P = .522).

CONCLUSION

The results indicate that although relatively high levels of return-to-sport outcomes were achieved at 24 months compared with those previously reported in the literature, correlations between objective clinical tests and return-to-sport outcomes may not occur. Clinical outcome measures may provide suitable baseline information; however, the results of this study suggest that clinicians may need to place greater emphasis on other outcome measures when seeking to objectively promote safe return to sport.

Key components and potential benefits of a comprehensive approach to women's musculoskeletal health

Over the last 40 years there has been a significant increase in the number of female athletes, as well as a rise in musculoskeletal injuries observed in women. There is sufficient evidence from past medical research identifying various musculoskeletal injuries and conditions that more commonly affect women, such as osteoarthritis, osteoporosis, stress fractures, and anterior cruciate ligament tears. Several women's sports medicine and musculoskeletal health programs have been developed throughout the United States in an attempt to provide more tailored care to the female athlete. The goal of a comprehensive approach to women's musculoskeletal health is to create an interdisciplinary team to facilitate treatment for a variety of injuries and related conditions. This manuscript outlines the musculoskeletal conditions that commonly affect women and highlights the various etiologies of these sex disparities. We discuss the role of interdisciplinary women's musculoskeletal health and sports medicine programs, and define the potential benefits of such an approach. Future studies should focus on assessing the outcomes of multidisciplinary women's sports medicine programs as current literature in this area is lacking.

Anterior Cruciate Ligament Injuries in Baseball Players

PURPOSE

To determine common mechanisms of anterior cruciate ligament (ACL) injury in baseball players and to quantify the rate of return to play after primary surgical reconstruction and review intermediate clinical outcomes.

METHODS

Surgical injuries involving the ACL in youth, high school, collegiate, and professional baseball players were queried for an 11-year period (2001 to 2011). Over the study period, 42 baseball players were identified who had undergone arthroscopically assisted primary ACL reconstruction by 1 of 3 attending surgeons. Retrospective chart review was performed for all 42 patients to evaluate variables of age, level of competition, position, mechanism of injury, graft choice, and associated meniscal injuries. Twenty-six patients were reached for telephone survey and International Knee Documentation Committee questionnaire and they answered questions about their original injury and playing history.

RESULTS

The most common mechanism of injury was fielding, followed by base running. Infielders and outfielders (32% each) were the most commonly injured position, followed by pitchers (29%). Among the 32 players for whom it could be determined, 30 (94%) were able to return to playing baseball at a mean follow-up of 4.2 years (range 1.0 to 9.9 years). The mean International Knee Documentation Committee score was 84.0 (range 63 to 91). Among the 26 patients contacted for telephone interview, no one required revision ACL surgery, but 3 required a subsequent procedure for meniscal tear. Twenty-five patients (96%) denied any episodes of instability in the knee after reconstruction.

CONCLUSIONS

The overwhelming majority of baseball players that sustain ACL injuries do so while fielding or base running. Outfielders are significantly more likely than infielders to suffer ACL injuries while fielding versus base running. The results with respect to return to play are promising, as nearly all patients were able to return to baseball and none required a revision ACL surgery at a mean follow-up of 4.2 years.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Exploring the High Reinjury Rate in Younger Patients Undergoing Anterior Cruciate Ligament Reconstruction

BACKGROUND

Younger age is being increasingly recognized as a risk factor for anterior cruciate ligament (ACL) graft rupture and contralateral ACL injury after ACL reconstruction. Recent reports estimate second ACL injury rates to be in the range of 20% to 40%, which is a significant concern and requires further exploration.

PURPOSE

The primary purpose was to determine the rates of graft rupture and injury to the contralateral native ACL in younger athletes. We also sought to explore the influence of sex and age groupings (<18 years vs 18-19 years at the time of surgery) on the risk of subsequent ACL injury.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

The study cohort consisted of 354 consecutive patients who were younger than 20 years when they underwent their first primary hamstring tendon autograft ACL reconstruction. The number of subsequent ACL injuries (graft rupture or a contralateral injury to the native ACL) was determined at a mean follow-up of 5 years (range, 3-10 years). Subgroup analysis included sex and age (<18 years vs 18-19 years at the time of surgery) comparisons. Descriptive statistics were calculated for the timing of ACL graft rupture and contralateral ACL injury.

RESULTS

The overall follow-up rate was 89% (316/354). Graft ruptures occurred in 57 patients (18%) at an average time of 1.8 years after surgery. Almost half (47%) occurred within the first postoperative year, and 74% occurred within the first 2 years. The highest graft rupture rate of 28.3% was in the youngest males (<18 years), and this was significantly higher than in females of the same age (12.9%), as well as in male patients older than 18 years (13.8%). Contralateral ACL injuries occurred in 56 patients (17.7%) at an average time of 3.7 years after surgery. There were no significant age- or sex-based differences for contralateral ACL injuries. The total number of patients who had at least 1 further ACL injury subsequent to the primary surgery was 110 (35%).

CONCLUSION

The high rate of subsequent ACL injury in younger patients was confirmed. Early graft ruptures were more prevalent in patients who underwent surgery when they were younger than 18 years versus those in the 18- to 19-year age group. Males had higher rates of graft rupture than did females, with the youngest males (<18 years) at the highest risk in the investigated cohort.

Surgical Indications and Technique for Anterior Cruciate Ligament Reconstruction Combined with Lateral Extra-articular Tenodesis or Anterolateral Ligament Reconstruction

After anterior cruciate ligament (ACL) rupture, anteroposterior and rotational laxity in the knee causes instability, functional symptoms, and damage to other intra-articular structures. Surgical reconstruction aims to restore the stability in the knee, and to improve function and ability to participate in sports. It also protects cartilage and menisci from secondary injuries. Because of persistent rotational instability after ACL reconstruction, combined intra-articular and extra-articular procedures are more commonly performed. In this article, an overview of anatomy, biomechanical studies, current gold standard procedures, techniques, and research topics are summarized.