Return-to-Sport Outcomes After Revision Anterior Cruciate Ligament Reconstruction Surgery

Combined Anterolateral Ligament Reconstruction Results in Better Knee Stability and More Satisfactory Subjective Outcomes in Non-Athlete Patients Undergoing Revision Anterior Cruciate Ligament Reconstruction

Background: Consensus has not yet been reached regarding combined anterior cruciate ligament reconstruction (ALLR) with revisional anterior cruciate ligament reconstruction (RACLR). We aimed to compare the clinical outcomes between patients who underwent isolated RACLR and those who underwent RACLR combined with ALLR. Methods: Between June 2010 and June 2021, 49 patients who underwent RACLR were retrospectively reviewed over a 24-month follow-up. Patients were categorized into the isolated RACLR (n = 37, group 1) or combined ALLR group (n = 12, group 2). Clinical outcomes were evaluated with several patient-reported outcome measures (PROMs) and minimal clinically important differences (MCIDs) for each PROM. The side-to-side difference (SSD) of the anterior instability was measured. The pivot-shift test was performed. Results: Baseline characteristics showed no differences between the groups. PROMs showed no significant differences between the groups at the 2-year follow-up. Group 2 was superior to group 1 in the MCID achievement rate for Lysholm knee and International Knee Documentation Committee (IKDC) subjective scores at 24 months postoperatively. At the final follow-up, the proportion of IKDC grade A in SSD for anterior laxity was higher in group 2 than in group 1 (58.3% versus [vs.] 18.3%, p = 0.009), and the proportion of pivot-shift grade 0 was also higher in group 2 (66.7% vs. 27.0%, p = 0.013). The "near return to activity" rate was also higher in group 2 than in group 1 (83.3% vs. 45.9%, p = 0.043). Conclusions: Combining ALLR with RACLR in non-athletes results in a higher proportion of patients with less mechanical graft failure and satisfactory clinical outcomes.

Revision ACL reconstruction in female athletes: current concepts

The challenge of revision anterior cruciate ligament (ACL) reconstruction lies in its complexity, varied presentation, and technical intricacies. A successful ACL reconstruction should allow patients to safely return to preinjury activities. However, it is only sometimes simple, and many risk factors and concurrent pathologies come into play. Evaluating and analysing the cause of failure and associated conditions is paramount to addressing them effectively. Despite a plethora of research and improvements in knowledge and technology, e gaps exist in issues such as optimal techniques of revision surgery, graft options, fixation, concurrent procedures, rehabilitation and protocol for return to sports of high-level athletes. Female athletes need additional focus since they are at higher risk of re-injury, suboptimal clinical outcomes, and lower rates of return to sport following revision reconstruction. Our understanding about injury prevention and the protection of ACL grafts in female athletes needs to be improved. This review focuses on the current state of revision ACL surgery in female athletes and provides recommendations and future directions for optimising outcomes in this high-risk group.

Quantifying the Performance of Professional Athletes Following Traumatic Tibial Fractures

INTRODUCTION

A tibial fracture is an uncommon, yet severe injury that occurs in professional athletes within all major sports leagues. These injuries are often debilitating for professional athletes and can require extensive rehabilitation prior to returning to play. The purpose of this study is to investigate the impact of a tibial fracture on athletic performance in all four major United States sports leagues.

METHODS

A publicly available professional sports database, Pro Sports Transactions, was queried for tibial injuries from January 01, 2015, to May 31, 2023. The search included all four major U.S. sports leagues. To quantify and compare athletic ability before and after injury, performance-based statistics were collected from standardized player ratings in periods surrounding the date of injury. The percent change in player performance was measured and stratified. The Pearson correlation test was used to analyze player demographics.

RESULTS

There were a total of 24 professional athletes who suffered 28 confirmed tibial fractures across all leagues. Upon return, there was a 14.7% decrease in overall player performance across all leagues. National Basketball Association, National Football League, and National Hockey League athletes had a decrease of 34.5%, 29.1%, and 14.2%, respectively, following their return to play. Major League Baseball players demonstrated an 8.1% increase in player performance following their recovery from tibial fracture.

CONCLUSION

Players who suffer tibial fractures often undergo immediate surgery and, in unfortunate cases, may require multiple subsequent procedures. Additionally, athletes spend several months recovering prior to their return. Upon return, athletes' performance may be decreased; however, further study is required to strengthen the association between player performance and tibial fracture recovery.

Determinants of Performance in Professional Soccer Players at 2 and 5 Years After ACL Reconstruction

BACKGROUND

A number of studies have investigated return to play after anterior cruciate ligament reconstruction (ACLR) in professional soccer players, but it is unclear which factors are associated with a return to the preinjury performance and ability to play over time.

PURPOSE

To identify factors that contribute to a professional soccer player's return to preinjury performance after ACLR, as well as to report their playing performance at 2 and 5 years after ACLR compared with their preinjury performance.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

A consecutive cohort of professional soccer players undergoing primary ACLR were analyzed between 2005 and 2019. A minimum 2-year follow-up was required. The effect of patient, surgical, and postoperative factors on performance rates, defined as a combination of league level and playing time, was evaluated with univariate and multivariate logistic regression models.

RESULTS

A total of 200 male professional soccer players were included. When combining league level and playing time, 30% of athletes returned to their preinjury performance at 2 years and 22% at 5 years. However, 53% of athletes returned to their preinjury performance for at least 1 season by year 5. At 2 years, a chondral lesion of grade 3 or 4 decreased the odds of return to preinjury performance (odds ratio [OR], 0.37; P = .010). Athletes receiving an ACLR with the addition of a lateral extra-articular tenodesis procedure were 2.42 times more likely to return to preinjury performance at 2 years than athletes with ACLR alone (P = .004). By 5 years after ACLR, athletes aged ≥25 years at the time of reconstruction were 3 times less likely to be performing at their preinjury performance (OR, 0.32; P < .001), and those with a grade ≥3 chondral lesion were >2 times less likely to be performing at their preinjury performance (OR, 0.43; P = .033).

CONCLUSION

The presence of >50% thickness chondral pathology, ACLR without lateral extra-articular tenodesis, and age >25 years at the time of surgery were all significant risk factors of worse performance rates after ACLR. Significant decreases in performance rates were noted at 2 and 5 years postoperatively.

A hamstring autograft diameter ≤ 8 mm is a safe option for smaller, lighter and female athletes who want to return to pivoting sports after ACL reconstruction : Results from a retrospective evaluation of a local ACL register

PURPOSE

To investigate the association between hamstring autograft diameter and ACL graft failure rate in athletes who successfully returned to pivoting sports after ACL reconstruction.

METHODS

Retrospective evaluation of ACL graft failure rates in athletes who underwent ACL reconstruction with all-inside hamstring autograft and successfully returned to pivoting sports following postoperative rehabilitation. Athletes were divided into a ≤ 8 mm group and a > 8 mm group. Data about return to pivoting sports and ACL graft failures after ACL reconstruction were collected via a digital questionnaire. ACL graft failures were in all cases confirmed by an orthopaedic surgeon and/or MRI. The association between hamstring autograft diameter and ACL graft failure rate was investigated using a Fisher's exact test in the subgroup of athletes who completed the digital questionnaire and returned to pivoting sports.

RESULTS

Two-hundred and twenty-nine of the 422 athletes who completed the digital questionnaire (54.2%) returned to a pivoting sport and were included for final analyses. Ninety-seven (42.4%) of the athletes who returned to sport were in the ≤ 8 mm group (8 graft failures) and 132 (57.6%) in the > 8 mm group (10 graft failures). There were significantly more women (49.5 and 13.6% respectively; p < 0.001) and significantly smaller (1.75 and 1.81 m respectively; p < 0.001), lighter (72.2 and 79.6 kg respectively; p < 0.001) and younger (23.6 and 26.1 years old respectively; p = 0.015) athletes in the ≤ 8 mm group compared to the > 8 mm group. There was no significant association between hamstring autograft diameter and ACL graft failure rate.

CONCLUSION

A hamstring autograft diameter of ≤ 8 mm is a legitimate option for smaller, lighter and female athletes without increasing the risk for ACL graft failure.

LEVEL OF EVIDENCE

III.

Poorer patient-reported knee function and quality of life, but not activity level, after revision ACL reconstruction compared with primary ACL reconstruction: a matched-pair analysis with a minimum 5-year follow-up

BACKGROUND

An appropriate method for comparing knee function and activity level between patients with primary and revision anterior cruciate ligament reconstruction (ACLR) is to perform a matched-group analysis. The aim was to assess and compare knee function, knee-related quality of life and activity level between patients with revision ACLR and primary ACLR at a minimum of 5 years of follow-up.

METHODS

Patients aged ≤ 40 years old who underwent revision ACLR between 2010 and 2015 and a matched control group (primary ACLR) (1:1) with age ± 2 years, year of ACLR, sex, and pre-injury sport and Tegner Activity Scale (TAS) were retrospectively identified in our clinic database. The preoperative Knee injury and Osteoarthritis Outcome Score (KOOS) and surgical data were extracted and analyzed. Patients were mailed KOOS and EQ-5D questionnaires at a minimum of 5-years after revision ACLR. Study-specific questions about knee function, limitation in sport, satisfaction, and activity level according to the TAS (all scales of 1-10, 10 best) were also asked by telephone.

RESULTS

Seventy-eight patients with a revision ACLR (mean age ± SD, 29.9 ± 6.0 years) matched with seventy-eight patients with a primary ACLR (30.2 ± 5.8 years) were included. The follow-up for the revision ACLR group was 7.0 ± 1.5 years and for the primary ACLR group 7.7 ± 1.6 years. The revision ACLR group reported poorer KOOS scores in all subscales (p < 0.05) except the Symptoms subscale, poorer EQ-5D VAS (mean 79.2 ± 20.1 vs 86.0 ± 20.1, p = 0.012), and less satisfaction with current knee function (median 7 (6-8) vs 8 (7-9), p < 0.001). Patients with revision ACLR also experienced greater limitation in sports (median 7 (4-8) vs 8 (6-9), p < 0.001). There were no significant differences in the EQ-5D (mean 0.86 ± 0.17 vs 0.89 ± 0.11, p = 0.427), activity level (median 2 (2-5) vs 4 (2-7), p = 0.229), or satisfaction with activity level (median 8 (5-9) vs 8 (6-10), p = 0.281) between the groups.

CONCLUSIONS

At a minimum 5-year follow-up, the revision ACLR group reported poorer knee function and quality of life, less satisfaction with knee function and a greater limitation in sports but no differences in activity level and satisfaction with activity level compared with the primary ACLR group.

Comparison of Patient-Reported Outcomes, Strength, and Functional Performance in Primary Versus Revision Anterior Cruciate Ligament Reconstruction

BACKGROUND

Clinical outcomes after revision anterior cruciate ligament reconstruction (ACLR) are not well understood.

HYPOTHESIS

Patients undergoing revision ACLR would demonstrate worse patient-reported outcomes and worse limb symmetry compared with a cohort undergoing primary ACLR.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

672 participants (373 with primary ACLR, 111 with revision ACLR, and 188 uninjured) completed functional testing at a single academic medical center. Descriptive information, operative variables, and patient-reported outcomes (International Knee Documentation Committee score, Knee injury and Osteoarthritis Outcome Score, and Tegner Activity Scale score) were assessed for each patient. Quadriceps and hamstring strength tests were conducted using a Biodex System 3 Dynamometer. Single-leg hop for distance, triple hop test, and the 6-m timed hop test were also assessed. Limb symmetry index (LSI) between the ACLR limb and contralateral limb was calculated for strength and hop testing. Normalized peak torque (N·m/kg) was calculated for strength testing.

RESULTS

No differences were found in group characteristics, excluding body mass (P < .001), or in patient-reported outcomes. There were no interactions between revision status, graft type, and sex. Knee extension LSI was inferior (P < .001) in participants who had undergone primary (73.0% ± 15.0%) and revision (77.2% ± 19.1%) ACLR compared with healthy, uninjured participants (98.8% ± 10.4%). Knee flexion LSI was inferior (P = .04) in the primary group (97.4% ± 18.4%) compared with the revision group (101.9% ± 18.5%). Difference in knee flexion LSI between the uninjured and primary groups, as well as between the uninjured and revision groups, did not reach statistical significance. Hop LSI outcomes were significantly different across all groups (P < .001). Between-group differences in extension in the involved limb (P < .001) were noted, as the uninjured group exhibited stronger knee extension (2.16 ± 0.46 N·m/kg) than the primary group (1.67 ± 0.47 N·m/kg) and the revision group (1.78 ± 0.48 N·m/kg). As well, differences in flexion in the involved limb (P = .01) were found, as the revision group exhibited stronger knee flexion (1.06 ± 0.25 N·m/kg) than the primary group (0.97 ± 0.29 N·m/kg) and the uninjured group (0.98 ± 0.24 N·m/kg).

CONCLUSION

At 7 months postoperatively, patients who had undergone revision ACLR did not demonstrate inferior patient-reported outcomes, limb symmetry, strength, or functional performance compared with patients who had undergone primary ACLR. Patients who had undergone revision ACLR exhibited greater strength and LSI than their counterparts with primary ACLR, but these parameters were still inferior to those of uninjured controls.

Comparison of Psychological Readiness to Return to Sport After Primary Versus Revision Anterior Cruciate Ligament Reconstruction

Background

Rates of return to preinjury level of play after anterior cruciate ligament (ACL) reconstruction (ACLR) remain unsatisfactory, particularly for patients who undergo revision surgery. Psychological readiness is associated with successful return to sport (RTS) and self-perceived preinjury sport performance.

Purpose

To compare psychological readiness at RTS between patients who underwent revision ACL autograft reconstruction and matched controls who underwent primary ACL autograft reconstruction.

Study Design

Cohort study; Level of evidence, 3.

Methods

Data were gathered using a single orthopaedic surgeon database of patients who underwent ACLR between 2015 and 2018. Patients who underwent revision ACLR and met the study criteria (N = 92) were matched by age, sex, graft type, and rehabilitation protocol to a control group of patients who underwent primary ACLR (n = 92). Functional assessment at release to play was examined using passive knee range of motion, single-leg squat, and single-leg hop testing. Self-reported outcomes included the International Knee Documentation Committee subjective function survey and the ACL-Return to Sport after Injury (ACL-RSI) psychological readiness scale. Time to release to play was recorded as the number of months needed to reach a ≥90% limb symmetry index from the date of the index ACLR. Data were assessed for normality using the Shapiro-Wilk test, and univariate general linear models were utilized with an alpha level of .05.

Results

The overall mean patient age was 29.9 ± 10 years, and 40% of patients were women. No significant differences between groups were noted in any of the baseline patient characteristics or surgical findings. At RTS, the mean ACL-RSI score was significantly lower in the revision surgery group (77.4 ± 19.4 vs 85.3 ± 17.4; P = .011). In addition, the revision surgery group returned to play significantly later than the primary surgery group (9.4 ± 2 vs 8.1 ± 1.3 months, respectively; P < .001).

Conclusion

When compared with primary ACL autograft reconstruction, revision reconstruction patients exhibited lower psychological readiness scores and a longer time to meet the objective criteria for RTS.

Registration

NCT03704376 (ClinicalTrials.gov identifier).

Comparative Study of ACL Reconstruction With Hamstring Versus Patellar Tendon Graft in Young Women: A Cohort Study From the New Zealand ACL Registry

BACKGROUND

Young female athletes are a specific population that is at high risk of primary anterior cruciate ligament (ACL) rupture and subsequent graft failure. Despite large numbers of ACL reconstructions being carried out in young women, there is limited analysis of outcomes in this group, leading to low levels of evidence for graft choice.

PURPOSE

To assess the effect of graft choice on ACL reconstruction failure rates among young women in New Zealand.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Prospective data captured by the New Zealand ACL Registry between April 2014 and March 2022 were reviewed. Young women aged 15 to 20 years were included. The primary outcome measure was ACL graft failure during the study period, with the key independent variable being graft type, either patellar or hamstring tendon autograft. This is presented as the rate per 100 patient-years and is compared between the 2 groups using the hazard ratio generated from a Cox proportional hazards regression. Secondary outcome measures were Marx activity scores and the Knee injury and Osteoarthritis and Outcome Score patient-reported outcome measure.

RESULTS

A total of 1261 primary ACL reconstructions in young women aged 15 to 20 years were reviewed. Hamstring tendon grafts were used in 797 (63%) reconstructions and patellar tendon graft in 464 (37%) reconstructions. Patients with a hamstring tendon graft had a graft failure rate of 7.7% compared with 1.1% in patients with a patellar tendon graft (hazard ratio, 6.1; 95% CI, 2.4-15.1; P < .001). The number of failures per 100 person-years was significantly higher in the hamstring group (2.05) compared with the patellar tendon group (0.37). No difference was noted at final follow-up between the hamstring tendon and patellar tendon groups when comparing patient-reported outcome measures during the follow-up period.

CONCLUSION

In the young female population of this study, the use of a patellar tendon graft was associated with reduced risk of graft failure and was not associated with an increase in knee morbidity. This highlights the importance of informed decision-making in this high-risk population when considering ACL reconstruction graft type.

Failure modes after anterior cruciate ligament reconstruction: a systematic review and meta-analysis

PURPOSE

The reason for graft failure after anterior cruciate ligament reconstruction (ACLR) is multifactorial. Controversies remain regarding the predominant factor and incidence of failure aetiology in the literature. This review aimed to provide a meta-analysis of the literature to evaluate the relative proportion of various failure modes among patients with ACLR failure.

METHODS

The PubMed, Embase, Cochrane Library, Web of Science, and EBSCO databases were searched for literature on ACLR failure or revision from 1975 to 2021. Data related to causes for ACLR surgical failure were extracted, and a random effects model was used to pool the results, which incorporates potential heterogeneity. Failure modes were compared between different populations, research methods, graft types, femoral portal techniques, and fixation methods by subgroup analysis or linear regression. Funnel plots were used to identify publication bias and small-study effects.

RESULTS

A total of 39 studies were analyzed, including 33 cohort studies and six registry-based studies reporting 6578 failures. The results showed that among patients with ACLR failure or revision, traumatic reinjury was the most common failure mode with a rate of 40% (95% CI: 35-44%), followed by technical error (34%, 95% CI: 28-42%) and biological failure (11%, 95% CI: 7-15%). Femoral tunnel malposition was the most common cause of the technical error (29%, 95% CI: 18-41%), with more than two times higher occurrence than tibial tunnel malposition (11%, 95% CI: 6-16%). Traumatic reinjury was the most common factor for ACLR failure in European populations and in recent studies, while technical errors were more common in Asian populations, earlier studies, and surgery performed using the transtibial (TT) portal technique. Biological factors were more likely to result in ACLR failure in hamstring (HT) autografts compared to bone-patellar tendon-bone (BPTB) autografts.

CONCLUSION

Trauma is the most important factor leading to surgical failure or revision following ACLR. Technical error is also an important contributing factor, with femoral tunnel malposition being the leading cause of error resulting in failure.

Meniscal and Articular Cartilage Predictors of Outcome After Revision ACL Reconstruction: A 6-Year Follow-up Cohort Study

BACKGROUND

Meniscal and chondral damage is common in the patient undergoing revision anterior cruciate ligament (ACL) reconstruction.

PURPOSE

To determine if meniscal and/or articular cartilage pathology at the time of revision ACL surgery significantly influences a patient's outcome at 6-year follow-up.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients undergoing revision ACL reconstruction were prospectively enrolled between 2006 and 2011. Data collection included baseline demographics, surgical technique, pathology, treatment, and scores from 4 validated patient-reported outcome instruments: International Knee Documentation Committee (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Marx Activity Rating Scale. Patients were followed up at 6 years and asked to complete the identical set of outcome instruments. Regression analysis assessed the meniscal and articular cartilage pathology risk factors for clinical outcomes 6 years after revision ACL reconstruction.

RESULTS

An overall 1234 patients were enrolled (716 males, 58%; median age, 26 years). Surgeons reported the pathology at the time of revision surgery in the medial meniscus (45%), lateral meniscus (36%), medial femoral condyle (43%), lateral femoral condyle (29%), medial tibial plateau (11%), lateral tibial plateau (17%), patella (30%), and trochlea (21%). Six-year follow-up was obtained on 79% of the sample (980/1234). Meniscal pathology and articular cartilage pathology (medial femoral condyle, lateral femoral condyle, lateral tibial plateau, trochlea, and patella) were significant drivers of poorer patient-reported outcomes at 6 years (IKDC, KOOS, WOMAC, and Marx). The most consistent factors driving outcomes were having a medial meniscal excision (either before or at the time of revision surgery) and patellofemoral articular cartilage pathology. Six-year Marx activity levels were negatively affected by having either a repair/excision of the medial meniscus (odds ratio range, 1.45-1.72; P≤ .04) or grade 3-4 patellar chondrosis (odds ratio, 1.72; P = .04). Meniscal pathology occurring before the index revision surgery negatively affected scores on all KOOS subscales except for sports/recreation (P < .05). Articular cartilage pathology significantly impaired all KOOS subscale scores (P < .05). Lower baseline outcome scores, higher body mass index, being a smoker, and incurring subsequent surgery all significantly increased the odds of reporting poorer clinical outcomes at 6 years.

CONCLUSION

Meniscal and chondral pathology at the time of revision ACL reconstruction has continued significant detrimental effects on patient-reported outcomes at 6 years after revision surgery.

Patient-Reported Measures Associated with the Return to Pre-Injury Levels of Sport 2 Years after Anterior Cruciate Ligament Reconstruction

The International Knee Documentation Committee Subjective Knee Form (IKDC2000) and the Knee Injury and Osteoarthritis Outcome Score (KOOS) are knee-specific measures. However, their association with a return to sports after anterior cruciate ligament reconstruction (ACLR) is unknown. This study aimed to investigate the association between the IKDC2000 and the KOOS subscales and the return to the same pre-injury level of sport two years after ACLR. Forty athletes that were two years post-ACLR participated in this study. Athletes provided demographic information, filled out the IKDC2000 and KOOS subscales, and indicated whether they returned to any sport and whether they returned to the same pre-injury level (same duration, intensity, and frequency). In this study, 29 (72.5%) athletes returned to play any sport and eight (20%) returned to the same pre-injury level. The IKDC2000 (r: 0.306, p = 0.041) and KOOS quality of life (KOOS-QOL) (r: 0.294, p = 0.046) significantly correlated with the return to any sport, but it was age (r: -0.364, p = 0.021), BMI (r: -0.342, p = 0.031), IKDC2000 (r: 0.447, p = 0.002), KOOS-pain (r: 0.317, p = 0.046), KOOS sport and recreation function (KOOS-sport/rec)(r: 0.371, p = 0.018), and KOOS QOL (r: 0.580, p > 0.001) that significantly correlated with a return to the same pre-injury level. High KOOS-QOL and IKDC2000 scores were associated with returning to any sport, and high KOOS-pain, KOOS-sport/rec, KOOS-QOL, and IKDC2000 scores were all associated with returning to the same pre-injury level of sport.

Tunnel Management in Revision Anterior Cruciate Ligament Reconstruction: Current Concepts

Bone tunnel-related complications are frequently encountered during revision anterior cruciate ligament reconstruction (ACLR). Issues with tunnel positioning, enlargement, containment, and hardware interference may complicate surgery and compromise outcomes. As a result, several strategies have emerged to address these issues and optimize results. However, a systematic, unified approach to tunnel pathology in revision ACLR is lacking. The purpose of this review is to highlight the current state of the literature on bone tunnel complications and, although extensive literature on the subject is lacking, present an updated approach to the evaluation and management of tunnel-related issues in revision ACLR.

Revision Soft-Tissue Allograft Anterior Cruciate Ligament Reconstruction Is Associated With Lower Patient-Reported Outcomes Compared With Primary Anterior Cruciate Ligament Reconstruction in Patients Aged 40 and Older

PURPOSE

To evaluate patient-reported outcomes (PROs) and graft failure rates in revision allograft anterior cruciate ligament reconstruction (ACLR) in patients aged 40 and older and compare them with primary ACLRs.

METHODS

Patients aged 40 and older who underwent arthroscopic soft-tissue allograft ACLR between 2005 and 2016 with a minimum 2-year follow-up were retrospectively reviewed. Patients were grouped based on revision versus primary ACLR. The rate of achieving an International Knee Documentation Committee (IKDC) patient acceptable symptom state (PASS) score was recorded. Patient satisfaction, PROs, and graft failure were compared between groups using the χ² test, Fisher exact test, and Mann-Whitney U test.

RESULTS

We identified 32 patients who underwent revision ACLR and 201 patients who underwent primary ACLR aged 40 and older who met inclusion criteria with a mean follow-up of 6.2 and 6.9 years, respectively (P = .042). There was a lower rate of concomitant meniscal repair in the primary ACLR group (6% vs 21.9%, P = .007) There were no other differences in chondral injuries, mechanism of injury, or meniscal injuries between groups. The median IKDC score was greater in the primary ACLR group as compared with the revision ACLR group (83.9 vs 70.6, P < .001). Patients who underwent revision ACLR were less likely to achieve the IKDC PASS threshold (82.5% vs 56.3%, P = .001) and were less likely to report satisfaction as compared with patients who underwent primary ACLR (90.5% vs 78.1%, P =.038). No difference in graft failure rates was identified between groups (8% vs 15.6%, P = .180).

CONCLUSIONS

Revision allograft ACLR in patients aged 40 and older was associated with lower PROs compared with primary ACLR. Patients who underwent revision ACLR failed to meet the IKDC PASS threshold more often and were dissatisfied with procedure results more than twice as often as patients that underwent primary ACLR.

LEVEL OF EVIDENCE

III, retrospective cohort study.

Rates and Levels of Elite Sport Participation at 5 Years After Revision ACL Reconstruction

BACKGROUND

There is a paucity of data regarding return to play (RTP), level of competition, and longevity of play after revision of anterior cruciate ligament (ACL) reconstruction (ACLR) in elite athletes.

PURPOSE

To report RTP rates and competition levels in elite athletes at the point of RTP, as well as at 2 and 5 years after revision ACLR, and the effect of meniscal and chondral pathology at revision surgery on these outcomes.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A retrospective review of a consecutive series of all revision ACLRs undertaken by the senior author between 2009 and 2019, with a minimum 2-year follow-up, was carried out. Outcome measures were RTP rates and competition level.

RESULTS

A total of 49 knees in 48 elite athletes met the inclusion criteria. After revision ACLR, 43 (87.8%) elite athletes achieved RTP, of whom 75.5% were at the same level. At 2 years after surgery, 39 (79.6%) were still playing, 25 (51%) at the same level; at 5 years after surgery, 20 (44.4%) were still playing, 9 (20%) at the same level. Elite athletes with <50% thickness or no articular cartilage lesions were more likely to RTP (94.6% vs 66.7%; P = .026), as well as return to the same competition level (83.8% vs 50%; P = .047), compared with those with ≥50% thickness chondral lesions. Those without medial meniscal pathology were more likely to RTP at the same level after revision surgery (94.4% vs 64.5%; P = .036). The median time elite athletes continued to play after revision ACLR was 73 months (95% CI, 43.4-102.6); 23 months at the same level (95% CI, 13.6-32.4). The probability of still playing at 5 years after surgery was 55.9%, with a 22.5% chance of maintaining preinjury competition level.

CONCLUSION

In elite athletes, RTP rates and competition level decreased over time after revision ACLR. The presence of >50% thickness chondral pathology was associated with lower RTP rates and competition level at RTP time, while medial meniscal pathology was associated with lower competition level at RTP.

Revision anterior cruciate ligament reconstruction: Return to sports at a minimum 5-year follow-up

BACKGROUND

Between 43% and 75% of patients who undergo primary anterior cruciate ligament (ACL) surgery return to sport activity. However, after a revision ACL reconstruction (ACLR) the rate of return to sports is variable. A few publications have reported returns to sports incidence between 56% to 100% after revision ACLR.

AIM

To determine return to sports and functional outcomes after a single-stage revision ACLR with a 5-year minimum follow-up at a single institution.

METHODS

All patients operated between 2010 and 2016 with a minimum 5 years of follow-up were included. Type of sport, intensity, frequency, expectation, time to return to sport and failure rate were recorded. Lysholm, Tegner and International Knee Documentation Committee forms were evaluated prior to the first ACLR surgery, at 6 mo after primary surgery and after revision ACLR at 5 years minimum of follow-up. Objective stability was tested with the knee arthrometer test (KT-1000 knee arthrometer, Medmetric Corp).

RESULTS

A total of 41 patients who underwent revision ACLR during that period of time were contacted and available for follow-up. Median patient age at time of revision was 29 years old [interquartile range (IQR): 24.0-36.0], and 39 (95.0%) were male. The median time from revision procedure to follow-up was 70 mo (IQR: 58.0-81.0). Regarding return to sports, 16 (39.0%) were at the same level compared to preinjury period, and 25 patients (61.0%) returned at a lower level. Sixty-three percent categorized the sport as very important and 37.0% as important. One patient (2.4%) failed with a recurrent ACL torn. Mean preoperative Lysholm and subjective International Knee Documentation Committee scores were 58.8 [standard deviation (SD) 16] and 50 (SD 11), respectively. At follow-up, mean Lysholm and subjective International Knee Documentation Committee scores were 89 (SD 8) and 82 (SD 9) (P = 0.0001). Mean Tegner score prior to primary ACLR was 6.7 (SD 1.3), 5.1 (1.5 SD) prior to revision ACLR and 5.6 (1.6 SD) at follow-up (P = 0.0002). Overall, knee arthrometer test measurement showed an average of 6 mm (IQR: 4.0-6.0) side-to-side difference of displacement prior to revision ACLR and 3mm (IQR: 1.5-4.0) after revision.

CONCLUSION

Almost 40.0% of patients returned to preinjury sports level and 60.0% to a lower level. These may be useful when counseling a patient regarding sports expectations after a revision ACLR.

Choice of Patient-Reported Outcome Measures for Midterm Assessment After Anterior Cruciate Ligament Reconstruction Surgery

BACKGROUND

Patient-reported outcome measures (PROMs) have become increasingly popular for assessing subjective elements of a patient's condition. Two frequently used knee-related PROMs after anterior cruciate ligament reconstruction (ACLR) surgery are the International Knee Documentation Committee Subjective Knee Form (IKDC-SKF) and the Knee injury and Osteoarthritis Outcome Score (KOOS). However, completing the full versions of both measures represents a considerable responder burden.

PURPOSE

To compare a variety of KOOS short forms with each other as well as the IKDC-SKF in a large sample of ACLR patients between 2 and 6 years after surgery.

STUDY DESIGN

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

METHODS

The KOOS and IKDC-SKF were administered between 2 and 6 years (mean, 3 years) after ACLR surgery to a cohort of 832 patients (men, n = 489; women, n = 343). Two single-item assessment numerical evaluations were also completed for knee function and satisfaction. The following short form versions were calculated from the full KOOS: the KOOS-12 short form, KOOS-Physical Function Short form (KOOS-PS), KOOS-Joint Replacement Short form (KOOS-JR), and KOOS-Global. Descriptive statistics were calculated for all PROMs and associations between measures were explored using nonparametric (Spearman rho) correlations. Floor or ceiling effects were considered present if >15% of patients reported the worst (floor effect) or best (ceiling effect) possible score. Age and sex comparisons were also made for each PROM.

RESULTS

Ceiling effects were present for all KOOS short form versions. They were highly evident for the KOOS-JR and KOOS-PS (37%-44%), but they were only marginally above the threshold for the KOOS-12 and KOOS-Global (16%). The KOOS-12 and KOOS-Global had the highest correlation with the IKDC-SKF but only explained 58% to 59% of the variance in scores. The KOOS-12 and KOOS-Global were very highly correlated (ρ = 0.98). Only moderate correlations were seen between the single-item assessments and the IKDC-SKF or various KOOS short forms. There was a negligible association between patient age and PROM scores, but there was no significant sex difference for any of the PROMs.

CONCLUSION

The IKDC-SKF together with either the KOOS-Global or KOOS-12 may provide a comprehensive range of knee-related PROMs with minimized responder burden at 2 to 6 years after ACLR.

Revision Anterior Cruciate Ligament Reconstruction after Surgical Management of Multiligament Knee Injury

The purpose of this study is to determine factors associated with the need for revision anterior cruciate ligament reconstruction (ACLR) after multiligament knee injury (MLKI) and to report outcomes for patients undergoing revision ACLR after MLKI. This involves a retrospective review of 231 MLKIs in 225 patients treated over a 12-year period, with institutional review board approval. Patients with two or more injured knee ligaments requiring surgical reconstruction, including the ACL, were included for analyses. Overall, 231 knees with MLKIs underwent ACLR, with 10% (n = 24) requiring revision ACLR. There were no significant differences in age, sex, tobacco use, diabetes, or body mass index between cohorts requiring or not requiring revision ACLR. However, patients requiring revision ACLR had significantly longer follow-up duration (55.1 vs. 37.4 months, p = 0.004), more ligament reconstructions/repairs (mean 3.0 vs. 1.7, p < 0.001), more nonligament surgeries (mean 2.2 vs. 0.7, p = 0.002), more total surgeries (mean 5.3 vs. 2.4, p < 0.001), and more graft reconstructions (mean 4.7 vs. 2.7, p < 0.001). Patients in both groups had similar return to work (p = 0.12) and activity (p = 0.91) levels at final follow-up. Patients who had revision ACLR took significantly longer to return to work at their highest level (18 vs. 12 months, p = 0.036), but similar time to return to their highest level of activity (p = 0.33). Range of motion (134 vs. 127 degrees, p = 0.14), pain severity (2.2 vs. 1.7, p = 0.24), and Lysholm's scores (86.3 vs. 90.0, p = 0.24) at final follow-up were similar between groups. Patients requiring revision ACLR in the setting of a MLKI had more overall concurrent surgeries and other ligament reconstructions, but had similar final outcome scores to those who did not require revision surgery. Revision ligament surgery can be associated with increased pain, stiffness, and decrease patient outcomes. Revision surgery is often necessary after multiligament knee reconstructions, but patients requiring ACLR in the setting of a MLKI have good overall outcomes, with patients requiring revision ACLR at a rate of 10%.

Single-Stage Revision Anterior Cruciate Ligament Reconstruction: Experience With 91 Patients (40 Elite Athletes) Using an Algorithm

BACKGROUND

The increased prevalence of anterior cruciate ligament (ACL) reconstruction has led to an increased need for revision ACL reconstructions. Despite the growing body of literature indicating that single-stage revision ACL reconstruction can yield good outcomes, there is a lack of data for determining when and how to safely perform a single-stage revision.

PURPOSE

To assess the outcomes, graft failure rates, and return-to-play rates of a decision-making algorithm for single-stage revision ACL reconstruction.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

We reviewed a consecutive series of revision ACL reconstructions performed by the senior author between September 2009 and July 2016 with minimum 2-year follow-up. All patients were assessed, and decision making was undertaken according to the algorithm. Outcomes measured were further surgery, graft rerupture, re-revision, Tegner score, and Knee injury and Osteoarthritis Outcome Score (KOOS). For the elite athlete population, return-to-play time, duration, and level of play after surgery as compared with preinjury were also determined.

RESULTS

During this period, 93 procedures were performed in 92 patients (40 elite athletes). Two 2-stage procedures were undertaken, leaving 91 single-stage procedures (91 patients) to form the basis for further study. At a mean 4.3 years (SD, 2.2 years) after surgery, there had been 2 re-revisions (2.2%) and 2 further instances of graft failure that had not been re-revised (total graft failure rate, 4.4%). There were 17 subsequent procedures, including 6 arthroscopic partial meniscectomies, 5 removals of prominent implants, and 1 total knee arthroplasty. The mean Tegner score was 8.02 before graft rerupture and 7.1 at follow-up. At follow-up, the mean KOOS outcomes were 79.3 for Symptoms, 88.0 for Pain, 94.2 for Activities of Daily Living, 73.6 for Sport, and 68.9 for Quality of Life. Of 40 elite athletes, 35 returned to play at a mean 11.2 months (SD, 3.6 months) after surgery.

CONCLUSION

Single-stage revision ACL reconstructions can be performed reliably in the majority of patients, with good clinical outcomes, low rerupture rates, and high-return-to play rates, even in the elite athlete population.

Return to sports activity in the revision of anterior cruciate ligament reconstruction: A 2-6 Year follow-up study

INTRODUCTION

and Objective: The risk of an anterior cruciate ligament (ACL) injury in young patients and those with sports activity is increasing. Regarding the need of athletes with ACL re-rupture to return to sports, ACL revision surgery has received great importance. This study was conducted to evaluate the outcome of ACL reconstruction revision surgery in athletes.

METHOD

In general, 62 patients with primary surgery and 62 patients with revision ACL surgery were investigated in this study. The study subjects were matched in terms of age, gender, involved leg, injury mechanism, sports group, time of surgery, and the degree of cartilage injury and ankle meniscus rupture. The studied variables included age, gender, body mass index (BMI), sports group, infection, meniscus injuries, chondral lesion, time to return to sports, quality of return to sports, range of motion, Lachman's test, and knee injury and osteoarthritis outcome score (KOOS), International Knee Documentation Committee score, Lysholm, and Marx scores. They were obtained through the information in the patients' medical records and the questionnaire filled out by the participants and the examiner's physician through the follow-ups. Then, the collected data were imported into the SPSS software and underwent analysis.

RESULTS

The mean follow-up of patients was 49 months (in the range of 2-6 years). None of the patients had a chronic infection. The mean time to return to sports was 29.2 ± 3.2 and 35.3 ± 4.3 weeks in the primary surgery and revision surgery groups, respectively. In addition, 34 (54.8%) and 25 (40.3%) patients of the primary surgery and the revision surgery groups returned to the same level before injury, respectively. On the latest follow-up, the results of the Lachman test showed no significant difference between the two groups (P = 0.222) whereas Lysholm, IKDC, MARX, and KOOS scores on the latest follow-up in primary surgery were significantly higher than those of revision surgery (P < 0.001).

CONCLUSION

The rate of return to sports in revision surgery was 14.5% lower than that of primary surgery, and the average time of return to sports was six weeks. The rate of return to sports, similar to before the injury, was significantly lower in the revision group, females, the age group of over 25 years, and contact sports activity, and patients with a chondral lesion. All knee performance scores were also poorer in the revision surgery.

Patient-Reported Outcomes After Multiple-Revision ACL Reconstruction: Good but Not Great

Purpose

To evaluate the patient-reported and objective functional outcomes of patients undergoing multiple-revision anterior cruciate ligament (ACL) reconstruction surgery. The secondary purpose was to determine failure rates and factors associated with failure, with a focus on posterior tibial slope.

Methods

All patients who underwent a repeat revision ACL reconstruction with a single surgeon over a 13-year period were identified. Chart data were obtained, including radiographic findings, operative details and findings, and postoperative examination findings. Failure was defined as subjective instability with evidence of graft incompetence on physical examination and MRI. Patients completed the International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC-SKF) and Tegner Activity Level Scale. Patients who had outcomes scores completed a minimum of 2 years postoperatively were included.

Results

Fourteen patients were available for follow-up; 12 underwent secondary revision procedures, and 2 underwent tertiary revisions. Three patients (21%) had subsequent failure of the revision graft with mean time to failure of 27 months. Posterior tibial slope was significantly higher in the failures than in the nonfailures (13.3˚; 95% CI 10.1-16.6 versus 10.1˚; 95% CI 6.7-11.4; P = 0.049). Eleven patients completed outcomes measures at a mean of 42 months postoperatively (range 24-79 months). The mean Tegner activity score was 6.3 at follow-up, compared with 8.3 prior to the original ACL injury. The mean IKDC-SKF score was 70 at follow-up.

Conclusion

Multiple revision ACL reconstruction surgery appears to have reasonable functional outcomes but is associated with a relatively high failure rate. Activity level following repeat revision surgery is diminished compared to the preinjury state, but most patients are able to return to recreational sports.

Level of Evidence

Therapeutic Study, Level IV.

Trauma and femoral tunnel position are the most common failure modes of anterior cruciate ligament reconstruction: a systematic review

PURPOSE

To improve outcomes of anterior cruciate ligament reconstruction (ACLR), it is important to understand the reasons for failure of this procedure. This systematic review was performed to identify current failure modes of ACLR.

METHODS

A systematic search was performed using PubMed, EMBASE, Cochrane, and annual registries for ACLR failures. Studies were included when failure modes were reported (I) of ≥ 10 patients and (II) at a minimum of two-year follow-up. Modes of failure were also compared between different graft types and in femoral tunnel positions.

RESULTS

This review included 24 cohort studies and 4 registry-based studies (1 level I, 1 level II, 10 level III, and 16 level IV studies). Overall, a total of 3657 failures were identified. The most common single failure mode of ACLR was new trauma (38%), followed by technical errors (22%), combined causes (i.e. multiple failure mechanisms; 19%), and biological failures (i.e. failure due to infection or laxity without traumatic or technical considerations; 8%). Technical causes also played a contributing role in 17% of all failures. Femoral tunnel malposition was the most common cause of technical failure (63%). When specifically looking at the bone-patellar tendon-bone (BPTB) or hamstring (HT) autografts, trauma was the most common failure mode in both, whereas biological failure was more pronounced in the HT group (4% vs. 22%, respectively). Technical errors were more common following transtibial as compared to anteromedial portal techniques (49% vs. 26%).

CONCLUSION

Trauma is the single leading cause of ACLR failure, followed by technical errors, and combined causes. Technical errors seemed to play a major or contributing role in large part of reported failures, with femoral tunnel malposition being the leading cause of failure. Trauma was also the most common failure mode in both BPTB and HT grafts. Technical errors were a more common failure mode following transtibial than anteromedial portal technique.

LEVEL OF EVIDENCE

IV.

The underlying mechanism of partial anterior cruciate ligament injuries to the meniscus degeneration of knee joint in rabbit models

Background

The diagnosis, treatment, and efficacy evaluation of anterior cruciate ligament (ACL) partial rupture remains controversial. This research aims to investigate the underlying mechanism of partial ACL injuries to the meniscus degeneration in the rabbit knee.

Methods

Sixty New Zealand white rabbits were randomly divided into three groups including an experimental group, a sham group (n = 6), and a blank control group (n = 6). The experimental group is composed of an anteromedial bundle (AMB) rupture group (n = 24) and a posterolateral bundle (PLB) rupture group (n = 24). Rabbits in the experimental group were subjected to right hind limbs knee surgery to induce ACL part injury under the arthroscopy. Finally, eight rabbits including 6 in the model group and 2 in the control group were sampled randomly on the 2nd, 4th, and 8th weeks respectively. We observed the typical form of the meniscus through HE staining. Expressions of inflammatory factors including interleukin-1β (IL-1β) and IL-17 in the knee joint fluid were determined by means of an ELISA. Analysis of the mRNA expressions of matrix metalloproteinases-13(MMP-13) was performed to evaluate the inflammatory mediators in the pathogenesis of the meniscus.

Results

HE staining results showed that the surface was rough and the tissues were loose displaying collagen fibers of varying thickness. Both IL-1β and IL-17 in the synovial fluid and the positive rate of MMP-13 in addition to MMP-13 mRNA showed a demonstrable increase treads from the 2nd to the 8th week. The significant difference was found (P < 0.05) compared to the control group.

Conclusion

We conclude that the elevated levels of IL-1β and IL-17, along with increased MMP13 expression, resulted in meniscus degradation in the rabbit knee joint model with partial ACL injury.

Differences in Strength, Patient-Reported Outcomes, and Return-to-Play Rates Between Athletes With Primary Versus Revision ACL Reconstruction at 9 Months After Surgery

Background:

Patient-reported outcomes and return-to-play (RTP) rates are inferior after revision anterior cruciate ligament reconstruction (ACLR) compared with primary ACLR. Physical properties such as maximal, explosive, and reactive strength influence reinjury and RTP rates after ACLR. No study has compared these outcomes between revision and primary ACLR.

Purpose:

To compare maximal, explosive, and reactive strength of the ACLR limb, as well as patient-reported outcomes and RTP rates between primary and revision ACLR at 9 months after surgery.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

A comparative study was performed at 9 months after surgery for 344 male athletes who had undergone ACLR (298 primary, 46 revision). Maximal strength of the ACLR limb was measured by means of isokinetic dynamometry. Explosive strength was measured by use of single-leg countermovement jump height, and reactive strength was measured by single-leg drop jump. Patient-reported outcomes and responses to RTP questionnaires were recorded for both groups.

Results:

The primary ACLR group had higher scores than the revision ACLR group for single-leg countermovement jump height (P = .02) and single-leg drop jump reactive strength index (P = .01) on the ACLR limb. No significant difference was observed between groups on maximal strength of the quadriceps or hamstring, and no significant difference in limb symmetry index was observed between groups on any strength or jump test. The primary ACLR group demonstrated higher scores on the Marx Activity Rating Scale (P = .03) and the Anterior Cruciate Ligament–Return to Sport after Injury scale (P < .001). Athletes in the primary ACLR group were more likely to have returned to sport (P < .001).

Conclusion:

At 9 months after surgery, athletes who had undergone revision ACLR achieved maximal strength similar to that of athletes who had undergone primary ACLR. However, athletes who had revision ACLR demonstrated lower scores on explosive and reactive strength tests. Athletes who underwent revision ACLR had lower RTP rates at 9 months after surgery, potentially due to explosive and reactive strength deficits and lower perceived readiness for RTP.

Revision ACL Reconstruction in Children and Adolescents

BACKGROUND

Revision anterior cruciate ligament (ACL) reconstruction in pediatric patients has not been well studied. The purpose of this study was to assess the demographics, technique, and results of ACL revision surgery in children and adolescents.

METHODS

This was a retrospective case series with outcomes assessment of patients 18 years old and younger who underwent revision ACL surgery over a 16-year period at a single institution. Medical records were reviewed for demographics, clinical and operative data, and patients were contacted for outcomes at a minimum of 1 year after revision surgery.

RESULTS

Ninety revision ACL reconstructions were performed by 7 surgeons in 88 patients (44 male, 44 female). Average patient age at the time of revision was 16.6 years (SD, 1.7), and 28.8% of patients were skeletally immature. Time to failure after primary ACL reconstruction was 1.28 years (SD, 1.1) and revision surgery was performed 1.56 years (SD, 1) after the index procedure. Revision graft type included allograft (61.1%), patellar tendon (21.1%), hamstring (16.7%), and iliotibial band (1.1%). There was a 20% graft reinjury rate. Subsequent surgical procedures after revision were required in 25.5% of knees. Twenty percent of revision reconstructions had contralateral ACL injuries, and this percentage was higher (33%) among those who went on to injure their revision graft. Median outcome scores collected from 44 patients (50%) at a mean of 5.1 years following surgery (SD, 3.4) were: Pedi-IKDC 79.9, Lysholm 84.5, and Tegner 9.0. Sixty-nine percent of patients reported returning to sports, however, only 55.2% of these reported being able to return to the same level of play.

CONCLUSIONS

Revision ACL reconstruction in pediatric patients was associated with suboptimal patient-reported outcomes, high complication rates, relatively high graft retear rates, high risk of contralateral ACL injury, and compromised return to sports rates.

LEVEL OF EVIDENCE

Level IV.

Factors Influencing Return to Play and Second Anterior Cruciate Ligament Injury Rates in Level 1 Athletes After Primary Anterior Cruciate Ligament Reconstruction: 2-Year Follow-up on 1432 Reconstructions at a Single Center

BACKGROUND

Despite the importance of return-to-play (RTP) rates, second anterior cruciate ligament (ACL) injury rates, and patient-reported outcomes of athletes returning to sports after ACL reconstruction (ACLR), these outcomes have not been evaluated together across a single cohort nor the pre- and intraoperative factors influencing outcomes explored.

PURPOSE

To prospectively report outcomes after ACLR relating to RTP, second ACL injury, and International Knee Document Committee (IKDC) scores in a large cohort of athletes at a single center to examine the influence of pre- and intraoperative variables on these outcomes.

DESIGN

Cohort study; Level of evidence, 3.

METHODS

A consecutive cohort of 1432 athletes undergoing primary ACLR by 2 orthopaedic surgeons was followed up prospectively more than 2 years after surgery. Pre- and intraoperative findings were reported with outcomes at follow-up relating to RTP, second ACL injury, and IKDC. Between-group differences for each outcome were reported and the predictive ability of pre- and intraoperative variables relating to each outcome assessed with logistic regression.

RESULTS

There was >95% follow-up 2 years after surgery. The RTP rate was 81%, and of those who returned, 1.3% of those with patellar tendon grafts and 8.3% of those with hamstring grafts experienced ipsilateral rerupture (hazard ratio, 0.17). The contralateral ACL injury rate was 6.6%, and the IKDC score at follow-up was 86.8, with a greater proportion of patients with patellar tendon grafts scoring <80 on the IKDC (odds ratio, 1.56; 95% CI, 1.15-3.12). There was no relationship between time to RTP and second ACL injury, and there was a moderate correlation between ACL-Return to Sport After Injury score and RTP at follow-up (P < .001, rho = 0.46). There were a number of differences in pre- and intraoperative variables between groups for each outcome, but they demonstrated a poor ability to predict outcomes in level 1 athletes at 2-year follow-up.

CONCLUSION

Findings demonstrated high overall RTP rates, lower reinjury rates with patellar tendon graft after 2-year follow-up in level 1 athletes, and no influence of time to RTP on second ACL injury. Despite differences between groups, there was poor predictive ability of pre- and intraoperative variables. Results suggest pre- and intraoperative variables for consideration to optimize outcomes in level 1 athletes after ACLR, but future research exploring other factors, such as physical and psychological recovery, may be needed to improve outcome prediction after ACLR.

REGISTRATION

NCT02771548 (ClinicalTrials.gov identifier).

Outcome After Anterior Cruciate Ligament Revision

PURPOSE OF REVIEW

To describe the current literature related to anterior cruciate ligament (ACL) revision in terms of surgical aspects, graft choices, concomitant injuries, patient-reported outcome, return to sport, and objective measurement outcome.

RECENT FINDINGS

An ACL rupture is a common knee injury, and the number of primary ACL reconstructions is increasing, implying a subsequent increase of ACL revisions in the future. It is widely accepted that an ACL revision is surgically challenging with a myriad of graft options to choose from. In many cases, simultaneous injuries to the index limb including meniscal and chondral lesions, respectively, are observed in the setting of a secondary ACL injury. Furthermore, the general understanding is that an ACL revision results in inferior outcome compared with a primary ACL reconstruction. Surgical treatment of an ACL revision can be performed as one-stage or two-stage procedure depending on, for example, the presence of limb malalignments, concomitant injuries, and tunnel widening. Nonirradiated allografts and autologous patella tendon, hamstring tendon, and quadriceps tendon are feasible options for ACL revision. Concomitant injuries to the affected knee such as intraarticular chondral lesions are more common in the setting of an ACL revision compared with primary ACL reconstruction while a lower presence of concomitant meniscal pathology is reported at ACL revision. Patients undergoing ACL revision have lower clinical and patient-reported outcome and lower rates of return to sport when compared with primary ACL surgery cases. However, long-term follow-ups with large study cohorts evaluating outcome of ACL revision are limited. Further research is needed to confirm the present findings of this review.

Wearable inertial sensors and pressure MAT detect risk factors associated with ACL graft failure that are not possible with traditional return to sport assessments

Introduction

Anterior cruciate ligament reconstruction (ACLR) is associated with poor return to sport and high graft re-rupture rates. This study explored the use of a wearable inertial sensor (ViMove) that incorporates an accelerometer and gyroscope, and MatScan pressure sensing mat (TekScan, South Boston, Massachusetts, USA) to provide objective return-to-sport measures.

Methods

Three cohorts’ ACLR patients, non-athletic controls and elite athletes (Australian seven’s rugby Olympic Gold medallist). Patients performed biometric and functional tests (thigh circumference and triple hop) and the ViMove knee module (consisting of single and double leg squats, hops and box drops) for lower limb alignment assessment, concurrently with force plate.

Results

Elite athletes had less varus/valgus (VV) movement during ViMove exercises compared with the ACLR cohort, who in turn had less VV malalignment than controls. When analysing side-to-side differences, single leg squats and box drop were asymmetrical in the ACL group, with greater malalignment in the reconstructed leg (p<0.05). Subgroup analysis failed to differentiate who passed or failed current return to sport assessment. TekScan pressure plate detected differences in double leg landing and flight time while hopping not detected with ViMove, suggesting ACL patients compensate by offloading the reconstructed leg to improve coronal alignment during double leg activity.

Conclusion

The inertial sensor detected differences in motion for patients following ACLR, which are known to be associated with graft rupture and were not detected with functional return to sport testing. Coupling the device with data from a pressure plate provides a powerful assessment tool detecting alignment differences known to be associate with graft failure only previously detected in formal gait analysis.

Relationship Between Sports Participation After Revision Anterior Cruciate Ligament Reconstruction and 2-Year Patient-Reported Outcome Measures

BACKGROUND

Anterior cruciate ligament (ACL) revision cohorts continually report lower outcome scores on validated knee questionnaires than primary ACL cohorts at similar time points after surgery. It is unclear how these outcomes are associated with physical activity after physician clearance for return to recreational or competitive sports after ACL revision surgery.

HYPOTHESES

Participants who return to either multiple sports or a singular sport after revision ACL surgery will report decreased knee symptoms, increased activity level, and improved knee function as measured by validated patient-reported outcome measures (PROMs) and compared with no sports participation. Multisport participation as compared with singular sport participation will result in similar increased PROMs and activity level.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

A total of 1205 patients who underwent revision ACL reconstruction were enrolled by 83 surgeons at 52 clinical sites. At the time of revision, baseline data collected included the following: demographics, surgical characteristics, previous knee treatment and PROMs, the International Knee Documentation Committee (IKDC) questionnaire, Marx activity score, Knee injury and Osteoarthritis Outcome Score (KOOS), and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). A series of multivariate regression models were used to evaluate the association of IKDC, KOOS, WOMAC, and Marx Activity Rating Scale scores at 2 years after revision surgery by sports participation category, controlling for known significant covariates.

RESULTS

Two-year follow-up was obtained on 82% (986 of 1205) of the original cohort. Patients who reported not participating in sports after revision surgery had lower median PROMs both at baseline and at 2 years as compared with patients who participated in either a single sport or multiple sports. Significant differences were found in the change of scores among groups on the IKDC (P < .0001), KOOS-Symptoms (P = .01), KOOS-Sports and Recreation (P = .04), and KOOS-Quality of Life (P < .0001). Patients with no sports participation were 2.0 to 5.7 times more likely than multiple-sport participants to report significantly lower PROMs, depending on the specific outcome measure assessed, and 1.8 to 3.8 times more likely than single-sport participants (except for WOMAC-Stiffness, P = .18), after controlling for known covariates.

CONCLUSION

Participation in either a single sport or multiple sports in the 2 years after ACL revision surgery was found to be significantly associated with higher PROMs across multiple validated self-reported assessment tools. During follow-up appointments, surgeons should continue to expect that patients who report returning to physical activity after surgery will self-report better functional outcomes, regardless of baseline activity levels.

Return to Sport Following Revision Anterior Cruciate Ligament Reconstruction in Athletes: A Systematic Review

PURPOSE

To report the rate of return to sport following revision anterior cruciate ligament (ACL) reconstruction in athletes.

METHODS

A systematic review of the literature following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was conducted for athletes undergoing revision ACL reconstruction at a minimum 1-year follow-up. The primary outcome measure was return to sport following revision ACL reconstruction. Secondary outcomes were International Knee Documentation Committee score, Knee Injury and Osteoarthritis Outcome Score, Tegner and Lysholm scores, KT-1000 arthrometer measurements, and rates of ACL rerupture. A subjective analysis was performed, and data were summarized using forest plots, ranges, and tables.

RESULTS

Thirteen studies met the inclusion criteria. The rate of return to sport at any level ranged from 56% to 100%. The rate of return to sport at preinjury level ranged from 13% to 69%. The average time to return to sport ranged from 6.7 to 12 months. The average patient-reported outcome scores ranged from 43% to 86% (International Knee Documentation Committee score), 45% to 95% (Knee Injury and Osteoarthritis Outcome Score), 4.3 to 9 (Tegner), and 84% to 91% (Lysholm). KT-1000 arthrometer measurements ranged from 1.2 to 3.1 mm. Rates of ACL rerupture ranged from 0% to 20%.

CONCLUSIONS

This systematic review demonstrated a relatively high rate of return to sport at any level in patients who underwent revision ACL reconstruction, but a relatively low rate of return to sport at preinjury level of play. Patient-reported outcomes were favorable, showing improvement at follow-up from preoperative scores. Rates of ACL rerupture were high relative to those reported for primary ACL reconstruction. This study suggests that athletes may have difficulty resuming their previous level of sport following revision ACL reconstruction but have a good chance of returning to a lower level of play.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II-IV studies.

Expectations for Return to Preinjury Sport Before and After Anterior Cruciate Ligament Reconstruction

BACKGROUND

There is limited information about patient expectations regarding return to sport after anterior cruciate ligament reconstruction (ACLR). While it has generally been assumed that patients expect to return, it has also been acknowledged that expectations may change after surgery.

PURPOSE

To investigate return-to-sport expectations before and after ACLR and determine factors associated with changed expectations.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

The study sample consisted of 675 eligible patients (437 male, 238 female). Return-to-sport expectations were recorded preoperatively. Primary ACLR was performed in 595 patients (of whom 81 had a prior contralateral ACLR) and revision ACLR in 80 patients. At 12 months after surgery, the return to preinjury sport status was assessed along with patients' current sport expectations. The proportion of patients who expected to return to their preinjury level of sport was determined along with actual return rates. Logistic regression was performed to determine the factors associated with the decision to cease sport participation in patients who had expected to be able to return to their preinjury level of sport.

RESULTS

Overall, 84% of patients expected to be able to return to their preinjury level of sport. Expectations were higher for patients about to undergo their first ACLR, with 88% expecting to return, than for those about to undergo revision surgery or second primary ACLR (63% and 80% expected to return, respectively; P < .001 and P = .08, respectively). At 12 months after surgery, 24% of patients who expected to return to their preinjury level of sport had actually returned, and 15% of all patients had already decided to give up sport. In the regression models, being female ( P = .02) and having undergone previous ACLR ( P < .0001) were factors significantly associated with the decision to give up sport participation.

CONCLUSION

Patients had high expectations for returning to their preinjury level of sport at the time of undergoing initial ACLR. Expectations were lower for those who had undergone previous ACLR. Female patients and patients who had undergone previous ACLR were more likely to change their expectations and cease sport participation. These data can be used to provide patients with realistic return-to-sport expectations in the first postoperative year and highlight the challenge for patients who aim to return from multiple ACL injuries.

Low Rates of Return to Preinjury Sport After Bilateral Anterior Cruciate Ligament Reconstruction

BACKGROUND

Patients with bilateral anterior cruciate ligament (ACL) injuries tend to report worse results in terms of knee function and quality of life as compared with those with unilateral injury. There are limited data regarding return to preinjury sport in this group.

PURPOSE

To report return-to-sport rates for patients who had bilateral ACL reconstruction and to compare outcomes according to age and sex.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 107 patients (62 male, 45 female) who underwent primary ACL reconstruction surgery to both knees completed a detailed sports activity survey at a mean 5-year follow-up (range, 2.5-10 years). Follow-up also included the International Knee Documentation Committee subjective form, Marx Activity Scale, and Knee injury and Osteoarthritis Outcome Score-Quality of Life subscale. Rates of return to preinjury levels of sport were calculated for the whole cohort, and for further analysis, the group was divided according to age (<25 vs ≥25 years), sex, and time between the reconstruction procedures (<3 vs ≥3 years).

RESULTS

The rate of return to preinjury sport after bilateral ACL reconstruction was 40% (95% CI, 31%-50%), as compared with an 83% (95% CI, 74%-88%) return rate after the first reconstruction procedure. Although not statistically significant, return rates were higher for male versus female patients (47% vs 31%) and older versus younger patients (45% vs 31%). Of those who returned to their preinjury levels of sport after the second reconstruction, 72% thought that they could perform as well as before their ACL injuries. In contrast, only 20% thought that they could perform as well if they returned to a lower level. Fear of reinjury was the most common reason cited for failure to return to sport after the second reconstruction. Patient-reported outcome scores were higher for those who returned to their preinjury levels of sport but did not differ for sex and age.

CONCLUSION

Return-to-sport rates drop markedly after a second (contralateral) ACL reconstruction, with less than half of the investigated cohort returning to its preinjury level of sport. Return-to-sport outcomes are less than ideal for patients who have ACL reconstruction surgery to both knees.

Revision Anterior Cruciate Ligament Reconstruction in the Nonathlete Population

BACKGROUND

There is considerable literature about revision anterior cruciate ligament (ACL) reconstruction in athletes vut there is little published evidence about the same in the nonathletes. The injury itself may remain underdiagnosed and untreated in nonsports persons. This study highlights the high incidence of ACL injury in the nonathletic patient cohort, revision rates, and the outcomes of revision ACL reconstruction.

MATERIALS AND METHODS

856 nonathletic patients who underwent primary ACL reconstruction were included in this retrospective study. Patients were asked on phone whether they had undergone revision surgery and whether they had symptoms severe enough to seek reintervention. Clinical assessment and preoperative and postoperative International Knee Documentation Committee (IKDC) and Lysholm scoring were used to followup patients who underwent revision intervention.

RESULTS

Clinically, symptomatic revision rate was 5.9% (51 out of 856 patients), and 33 out of these 856 patients (3.9%) underwent revision ACL reconstruction. The reasons for revision were rupture of the previous graft in 21 and laxity (incompetence) of the graft in 12 patients. The mean preoperative and postoperative IKDC scores were 44.1 and 69.8, respectively, and the improvement was statistically significant (P < 0.001). The IKDC score following revision ACL reconstruction was significantly better in those patients who underwent revision <1 year following the onset of recurrent symptoms (P = 0.015). Meniscal tears were present in 47.6%, and chondral injuries were seen in 33.3% of patients. The tibial tunnel positioning was abnormal in 70% of patients. Femoral tunnel positioning was aberrant in all the patients.

CONCLUSIONS

The revision rate of primary ACL reconstruction of 5.9% in nonathletes and revision ACL reconstruction rate of 3.9% are similar to the reported revision rates of 2.9%-5.8% in athletic patients. Similar to athletes, suboptimal tunnel placement is the major contributor to failure in nonathletes also.

5-Year Survival of Pediatric Anterior Cruciate Ligament Reconstruction With Living Donor Hamstring Tendon Grafts

BACKGROUND

It is well accepted that there is a higher incidence of repeat anterior cruciate ligament (ACL) injuries in the pediatric population after ACL reconstruction (ACLR) with autograft tissue compared with adults. Hamstring autograft harvest may contribute to the risk for repeat ACL injuries in this high functional demand group. A novel method is the use of a living donor hamstring tendon (LDHT) graft from a parent; however, there is currently limited research on the outcomes of this technique, particularly beyond the short term.

PURPOSE/HYPOTHESIS

The purpose was to determine the medium-term survival of the ACL graft and the contralateral ACL (CACL) after primary ACLR with the use of an LDHT graft from a parent in those aged less than 18 years and to identify factors associated with subsequent ACL injuries. It was hypothesized that ACLR with the use of an LDHT provides acceptable midterm outcomes in pediatric patients.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Between 2005 and 2014, 247 (of 265 eligible) consecutive patients in a prospective database, having undergone primary ACLR with the use of an LDHT graft and aged less than 18 years, were included. Outcomes were assessed at a minimum of 2 years after surgery including data on ACL reinjuries, International Knee Documentation Committee (IKDC) scores, and current symptoms, as well as factors associated with the ACL reinjury risk were investigated.

RESULTS

Patients were reviewed at a mean of 4.5 years (range, 24-127 months [10.6 years]) after ACLR with an LDHT graft. Fifty-one patients (20.6%) sustained an ACL graft rupture, 28 patients (11.3%) sustained a CACL rupture, and 2 patients sustained both an ACL graft rupture and a CACL rupture (0.8%). Survival of the ACL graft was 89%, 82%, and 76% at 1, 2, and 5 years, respectively. Survival of the CACL was 99%, 94%, and 86% at 1, 2, and 5 years, respectively. Survival of the ACL graft was favorable in patients with Tanner stage 1-2 at the time of surgery versus those with Tanner stage 3-5 at 5 years (87% vs 69%, respectively; hazard ratio, 3.7; P = .01). The mean IKDC score was 91.7. A return to preinjury levels of activity was reported by 59.1%.

CONCLUSION

After ACLR with an LDHT graft from a parent in those aged less than 18 years, a second ACL injury (ACL graft or CACL injury) occurred in 1 in 3 patients. The 5-year survival rate of the ACL graft was 76%, and the 5-year survival rate of the CACL was 86%. High IKDC scores and continued participation in sports were maintained over the medium term. Importantly, there was favorable survival of the ACL graft in patients with Tanner stage 1-2 compared with patients with Tanner stage 3-5 over 5 years. Patients with Tanner stage 1-2 also had a significantly lower incidence of second ACL injuries over 5 years compared with those with Tanner stage 3-5, occurring in 1 in 5 patients. Thus, an LDHT graft from a parent is an appropriate graft for physically immature children.

Prevalence of Posttraumatic Stress Disorder Symptoms Among Young Athletes After Anterior Cruciate Ligament Rupture

Background:

The risk of depression and the fear of reinjury were documented in recent investigations of patients after anterior cruciate ligament (ACL) ruptures. The extent of psychological trauma accompanying these injuries among young athletes, however, has never been assessed.

Hypothesis:

Posttraumatic stress disorder (PTSD) symptoms after ACL injury are present among young athletes with high athletic identities.

Study Design

Case series; Level of evidence, 4.

Methods:

Patients ≤21 years of age who had suffered an acute ACL rupture were consecutively recruited at a tertiary care center. Patients completed the Horowitz Impact of Event Scale - Revised (IES-R) to analyze for PTSD symptomatology, the Athletic Identity Measurement Scale, and an athlete specialization instrument created at the authors’ institution.

Results:

A total of 24 patients were consecutively recruited. The mean patient age was 14.5 ± 2.7 years, and 50% of patients were male. More than 87.5% of patients experienced avoidance symptoms, 83.3% acknowledged symptoms of intrusion, and 75% had symptoms of hyperarousal. Patients aged 15 to 21 years incurred a higher severity of PTSD symptoms than younger patients (P = .033). Female patients experienced greater emotional trauma than male patients (P = .017). Finally, patients with high athletic identities experienced greater emotional trauma than those with lesser athletic identities, but this finding was not statistically significant (P = .14).

Conclusion:

Following ACL rupture, young athletes experience significant emotional trauma, including symptoms of avoidance, intrusion, and hyperarousal. High school and college athletes, female athletes, and patients with high athletic identities may be most susceptible.

Criteria for return to running after anterior cruciate ligament reconstruction: a scoping review

Objective

To describe the criteria used to guide clinical decision-making regarding when a patient is ready to return to running (RTR) after ACL reconstruction.

Design

Scoping review.

Data sources

The MEDLINE (PubMed), EMBASE, Web of Science, PEDro, SPORTDiscus and Cochrane Library electronic databases. We also screened the reference lists of included studies and conducted forward citation tracking.

Eligibility criteria for selecting studies

Reported at least one criterion for permitting adult patients with primary ACL reconstruction to commence running postoperatively.

Results

201 studies fulfilled the inclusion criteria and reported 205 time-based criteria for RTR. The median time from when RTR was permitted was 12 postoperative weeks (IQR=3.3, range 5–39 weeks). Fewer than one in five studies used additional clinical, strength or performance-based criteria for decision-making regarding RTR. Aside from time, the most frequently reported criteria for RTR were: full knee range of motion or >95% of the non-injured knee plus no pain or pain <2 on visual analogue scale; isometric extensor limb symmetry index (LSI)>70% plus extensor and flexor LSI>70%; and hop test LSI>70%.

Conclusions

Fewer than one in five studies reported clinical, strength or performance-based criteria for RTR even though best evidence recommends performance-based criteria combined with time-based criteria to commence running activities following ACL reconstruction.

Increased incidence of anterior cruciate ligament revision surgery in paediatric verses adult population

PURPOSE

To evaluate the anterior cruciate ligament graft failure rate in a population of 1376 patients submitted to single-bundle anterior cruciate ligament reconstruction procedure. It was hypothesized that the younger the patient, the greater the chance of a new anterior cruciate ligament graft ligament injury.

METHODS

A retrospective chart review was performed on patients who had SB anterior cruciate ligament reconstruction between the years, 2001 and 2016, with a minimum post-operative follow-up period of 6 months. The patient population was divided into three groups, according to age: group 1-under 16 years old; group 2-between 16 and 18 years old; and group 3-older than 18 years old. Data collected included sex, laterality and graft choice data.

RESULTS

In group 1 (under 16 years old), there were 61 primary ACL surgeries performed and 15 (24.6%) revision ACL surgeries. In group 2 (between 16 and 18 years old), there was 57 primary ACL procedures, of which 10 (17.5%) were revisions. In the group 3 (older than 18 years of age), 1258 surgeries were done with 116 (9.2%) revisions.

CONCLUSION

The rate of ACL revision surgery in patients under 16 years of age was significantly higher than that found in patients older than 18 years old. When compared to the population between 16 and 18 years old, there were a higher number of failure cases, however, statistically non-significant.

LEVEL OF EVIDENCE

IV.

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.

Revision Anterior Cruciate Ligament Reconstruction Outcomes in Younger Patients: Medial Meniscal Pathology and High Rates of Return to Sport Are Associated With Third ACL Injuries

BACKGROUND

There are limited data evaluating the outcomes of revision anterior cruciate ligament (ACL) reconstruction surgery in younger patients despite recent reports that the rates of graft rupture are higher in young cohorts.

PURPOSE

To explore the outcomes of revision ACL reconstruction surgery in younger patients with the specific aims of determining the rates of third ACL injury and whether knee pathology at the time of revision surgery and return to sport were associated with further injury.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

The study cohort consisted of 151 consecutive patients who were aged 25 years or younger at the time of their first revision ACL reconstruction. The number of subsequent ACL injuries (graft rerupture or contralateral injury to the native ACL) was determined at a mean follow-up time of 4.5 years (range, 2-9 years). Surgical details were recorded, along with a range of sport participation outcomes. Contingency tables were used to assess the associations between subsequent ACL injury and return to sport, knee pathology, and the drilling of new femoral or tibial tunnels at revision surgery.

RESULTS

The follow-up rate was 85% (128/151). Graft reruptures occurred in 20 patients (16%) at a mean time of 2 years after revision surgery. Contralateral ACL injuries occurred in 15 patients (12%) at a mean time of 3.9 years. The total number of patients who had a third ACL injury was 35 (27%). There was a significant association between having medial meniscal pathology and sustaining a graft rerupture ( P = .03), but there was no association between graft rerupture and using the same tunnels from the primary procedure at revision surgery. After revision reconstruction, 68% of patients (95% CI, 55%-71%) returned to their preinjury level of sport, compared with 83% (95% CI, 69%-84%) after primary reconstruction in the same patients. Those who had a third ACL injury had a significantly higher rate of return to preinjury sport (83%) after the revision procedure than did the group that did not have further ACL injuries (62%, P = .02).

CONCLUSION

Younger patients are at significant risk of having multiple ACL injuries. The high rate of third ACL injuries presents a significant issue for future knee health in these young athletes. Medial meniscal pathology and returning to high-risk sport are factors that are significantly associated with the high multiple ACL injury rate in the young.

Medial meniscal and chondral pathology at the time of revision anterior cruciate ligament reconstruction results in inferior mid-term patient-reported outcomes

PURPOSE

Anterior cruciate ligament (ACL) injuries are frequently not isolated injuries and damage to the menisci and articular cartilage surfaces is common. The concomitant presence of meniscal and chondral damage has the potential to influence patient outcomes following ACL reconstruction surgery and especially following revision ACL reconstruction where these findings are more common. However, study results regarding the mid-term outcome have been inconsistent. The purpose of this study was to compare mid-term patient-reported outcomes and return to sport in patients with and without meniscal and chondral pathology at the time of revision ACL reconstruction surgery.

METHODS

A cohort of 180 patients (131 males, 49 female) with a mean age of 25.3 (SD 7.8) years participated at an average follow-up time of 4.6 (SD 1.3) years after revision ACL reconstruction surgery. All patients completed the IKDC Subjective, Marx Activity, KOOS-Quality of Life (QOL) and Single Numerical Assessment (SANE) scores. In addition, patients were asked to indicate the highest level of sport to which they had returned following their revision surgery. Any further injuries to either knee were also documented. Patients were grouped according to whether or not they had medial or lateral meniscal pathology at the time of revision surgery; and whether or not they had > 50% depth chondral damage (ICRS 3 or 4). All outcomes were compared between these groupings.

RESULTS

Patients with medial meniscal pathology had significantly lower Marx, KOOS-QOL and SANE scores than patients without. There were no differences in any outcome score between patients with and without lateral meniscal pathology. Patients with ICRS 3 or 4 chondral pathology had significantly lower scores on all patient-reported outcomes as well as a lower rate of return to the same level of pre-injury sport.

CONCLUSION

The presence of more severe chondral damage at the time of revision ACL reconstruction has a negative impact on functional outcomes, activity levels and return to sport rates. In addition, the presence of medial meniscal pathology was associated with significantly lower functional and quality of life scores than patients without pathology. These findings provide important clinically relevant data on the outcomes following revision ACL reconstruction with concomitant chondral and meniscal injury.

LEVEL OF EVIDENCE

III.

Anterior cruciate ligament revision with Achilles tendon allograft in young athletes

BACKGROUND

Return to sport after revision ACL reconstruction is a controversial topic, several studies reported the results of different techniques and graft in sportsman, presenting an incredibly wide range of return to the same pre-injury activity level, from 0% to 100%. The purpose of this study was to evaluate the clinical outcomes and return to sport rate in young athletes after non anatomic double-bundle revision ACL reconstruction with Achilles allograft.

HYPOTHESIS

The present revision technique was effective in terms of stability, return to sport and functional outcomes.

MATERIAL AND METHODS

All the athletes undergone Revision ACL reconstruction with non-irradiated Achilles tendon allograft with a non-anatomical double-bundle technique were included in the study. A split Achilles tendon allograft was used to reproduce the anteromedial (AM) bundle using the over-the-top position, while the posterolateral (PL) bundle was reconstructed through a femoral tunnel located in the anatomical PL footprint. Sport activity, knee function with Lysholm score, knee laxity and re-injury or re-operations were evaluated.

RESULTS

Twenty-six athletes (23 males, three females) with a mean age of 23.4±3.6 years were evaluated at a mean follow-up of 6.0±1.6 years. Overall 69% of patients returned to sport both at elite (44%) or county level (56%) after a mean 6.7±1.5 (3-9 range) months. The mean Lysholm score showed a significant improvement from 64.4±8.1 at pre-operative status to 83.8±11.3 at final follow-up (P<.0001). Seven patients (30%) were rated as excellent, nine (39%) as good, five (22%) as fair and 2 (9%) as poor. Three patients (12%) experienced a further graft rupture after a mean 2.6 years, (3.5 months-48 months range) and two had >5mm side-to-side difference at KT-1000. Therefore, the overall survival rate at mean six years follow-up was 81%.

CONCLUSION

The ACL revision with a double-bundle technique using Achilles tendon allograft was successful in 81% of athletes at six years mean follow-up.

TYPE OF STUDY AND LEVEL OF EVIDENCE

Retrospective case series, level IV.

Underappreciated Factors to Consider in Revision Anterior Cruciate Ligament Reconstruction: A Current Concepts Review

Primary anterior cruciate ligament (ACL) reconstructions (ACLRs) are being performed with increasing frequency. While many of these will have successful outcomes, failures will occur in a subset of patients who will require revision ACLRs. As such, the number of revision procedures will continue to rise as well. While many reviews have focused on factors that commonly contribute to failure of primary ACLR, including graft choice, patient factors, early return to sport, and technical errors, this review focused on several factors that have received less attention in the literature. These include posterior tibial slope, varus malalignment, injury to the anterolateral ligament, and meniscal injury or deficiency. This review also appraised several emerging techniques that may be useful in the context of revision ACL surgery. While outcomes of revision ACLR are generally inferior to those of primary procedures, identifying these potentially underappreciated contributing factors preoperatively will allow the surgeon to address them at the time of revision, ideally improving patient outcomes and preventing recurrent ACL failure.

Injury Recurrence Among High School Athletes in the United States: A Decade of Patterns and Trends, 2005-2006 Through 2015-2016

Background

As participation in high school athletics increases, so does the number of adolescents experiencing sports-related injury. Understanding injury patterns is an important component to developing and evaluating prevention and rehabilitation programs.

Purpose

To analyze recurrent injury rates and patterns among high school athletes, to compare recurrent injuries with new injuries, and to evaluate injury trends over time.

Study Design

Descriptive epidemiology study.

Methods

High school sports injury data on 24 sports were collected from 2005-2006 through 2015-2016 via the High School RIO (Reporting Information Online) surveillance system. Injury rates were calculated as number of injuries per 10,000 athletic exposures (AEs). Injury rate ratios and injury proportion ratios (IPRs) were calculated to compare differences among subgroups.

Results

Overall, 78,005 injuries were sustained during 40,195,806 AEs, for an injury rate of 19.41 per 10,000 AEs. Of these, 69,821 (89.5%) were new injuries, and 8184 (10.5%) were recurrent. The ankle was the most commonly injured body part among recurrent injuries, while the head/face was the most common body part that sustained new injuries. Ligament sprains were more often recurrent, while concussions were more commonly diagnosed as new, although concussions represented 16.7% of recurrent injuries. Trends for recurrent injuries over time were relatively stable. The proportion of athletes who had >3 weeks of time loss or medical disqualification (15.8% vs 13.3%; IPR, 1.19; 95% CI, 1.13-1.26) or who voluntarily withdrew from sport (2.5% vs 1.1%; IPR, 2.33; 95% CI, 2.00-2.73) was significantly greater for recurrent injuries than new injuries. Furthermore, a greater proportion of recurrent injuries resulted in surgery (8.1% vs 6.0%; IPR, 1.34; 95% CI, 1.24-1.46).

Conclusion

Although only 10.5% of all injuries were recurrent, they more frequently resulted in missing >3 weeks of playing time and were more often managed surgically when compared with new injuries. The rate of recurrent injuries has not increased over the past decade.

Clinical Outcomes in Revision Anterior Cruciate Ligament Reconstruction: A Meta-analysis

PURPOSE

The purpose of this meta-analysis was to determine overall objective graft failure rate, failure rate by graft type (allograft vs autograft reconstruction), instrumented laxity, and patient outcome scores following revision anterior cruciate ligament (ACL) reconstruction. Outcomes of interest were collected for all studies meeting the study inclusion criteria, but lower-level studies (level III/IV) were not pooled for quantitative synthesis due to high levels of heterogeneity in these study populations.

METHODS

A comprehensive search strategy was performed to identify studies reporting outcomes of revision ACL reconstruction. The primary outcome reported was graft failure. A meta-analysis comparing rate of failure by graft type was conducted using a random effects model. Studies also reported patient clinical outcome scores, including International Knee Documentation Committee (IKDC), Lysholm, and knee injury and osteoarthritis outcome scores (KOOS) and graft laxity.

RESULTS

Eight studies with 3,021 patients (56% male, 44% female) with an average age of 30 ± 4 years and mean follow-up time of 57 months were included. The overall objective failure rate was 6% (95% confidence interval [CI], 1.8%-12.3%). Mean instrumented laxity as side-to-side difference was 2.5 mm (95% CI, 1.9-3.1 mm). Mean IKDC subjective score was 76.99 (95% CI, 76.64-77.34), mean KOOS symptoms score was 76.73 (95% CI, 75.85-77.61), and mean Lysholm score was 86.18 (95% CI, 79.08-93.28). The proportion of patients with IKDC grade A or B was 85% (95% CI, 77%-91%). When the available data for failure rate were analyzed by graft type, autograft reconstruction had a failure rate of 4.1% (95% CI, 2.0%-6.9%), similar to allograft reconstruction at 3.6% (95% CI, 1.4%-6.7%).

CONCLUSIONS

In this meta-analysis, revision ACL reconstruction had failure rates similar to autograft or allograft reconstruction. Overall outcome scores for revision reconstruction have improved but appear modest when compared with primary ACL reconstruction surgery.

LEVEL OF EVIDENCE

Meta-analysis of Level II studies, Level II.

Combined Intra- and Extra-Articular Technique in Revision Anterior Cruciate Ligament Reconstruction

Purpose  The aim of the study was to evaluate the “over the top” (OTT) nonanatomical technique for revision of anterior cruciate ligament (ACL) reconstruction.

Methods  Twenty-four patients with a mean age of 31.9 ± 11.2 years underwent revision of ACL reconstruction using OTT technique. International Knee Documentation Committee (IKDC) score, Knee Injury and Osteoarthritis Outcome Score (KOOS), Lysholm score, Tegner score, Subjective Patient Outcome for Return to Sport (SPORTS) score, Anterior Cruciate Ligament-Return to Sport After Injury (ACL-RSI) scale, and KT-1000 evaluation were recorded at a mean follow-up of 30.7 ± 18.9 months.

Results  Postoperatively, the IKDC objective total score significantly improved ( p  = 0.0046). The KOOS, Lysholm, and Tegner scores also improved, but the results were not statistically significant (62.4 vs. 72.6, 6.5 vs. 75.8, and 4.1 vs. 6.0, respectively). The subjective IKDC evaluation score improved from an average of 51.1 points to 63.7 points at the last follow-up ( p  = 0.0027). The RTP prevalence was 81.8%, with 44.4% of the patients returning to the same preinjury level. According to the SPORTS score, 16.6% of patients played sport without limitations in activity and performance. The average ACL-RSI score was 52.1 ± 27.0. No major complications were reported. A total of 21.5% of patients underwent surgical removal of staples. The failure prevalence was 14.3% and the cumulative survivorship, calculated using the Kaplan–Meier method, was equal to 70% at 60 months of follow-up.

Conclusion  The OTT technique in the revision ACL reconstruction provided improvement in objective and subjective scores, good RTP prevalence, and acceptable rate of complication and failure. One of the advantages was the possibility to avoid the femoral tunnel.

Level of Evidence  Level IV, therapeutic case series.

A Retrospective Analysis of Concurrent Pathology in ACL-Reconstructed Knees of Elite Alpine Ski Racers

Background:

Anterior cruciate ligament (ACL) tear is the most frequent injury in alpine ski racing, and there is a high prevalence of ACL reinjury. Limited data exist on the concurrent pathology with primary ACL tears in elite alpine ski racers and the magnitude of injury progression after primary ACL reconstruction (ACLR).

Purpose:

To evaluate (1) the involvement of intra-articular and multiligament pathologies at the time of primary ACLR, (2) the subsequent progression in meniscal/chondral injuries, and (3) the occurrence of ACL reinjury in elite alpine ski racers.

Study Design:

Case series; Level of evidence, 4.

Methods:

Primary ACLR operative reports (n = 28) were obtained for 32 elite alpine ski racers along with the reports of 20 operative procedures that occurred subsequent to primary ACLR. Operative reports were evaluated to identify the presence/location of multiligament injury, meniscal tears, and chondral lesions.

Results:

At the time of primary ACLR, a majority of knees (82%; 23/28) demonstrated concurrent injury compared with isolated ACL tears; 32% of knees sustained multiligament injuries (9/28), and 8 involved the ipsilateral medial collateral ligament (MCL). Of the ACL-injured knees, 54% had chondral lesions, of which 73% were sustained in the lateral knee compartment, and 82% of meniscal tears (14/17) were complex in nature. Bilateral ACL tears were seen in 22% of the participants, and 28% underwent ACL revision. In the case of ACL revision or future meniscal/chondral surgery, 60% of meniscal tears and 80% of chondral lesions had worsened since the time of primary ACLR.

Conclusion:

Concurrent injury was common in this group of elite ski racers. Primary ACL tears were typically accompanied by lateral compartment chondral lesions and complex meniscal tears that worsened over time. ACL/MCL tears were the most common multiligament injury pattern.