Does a Delay in Anterior Cruciate Ligament Reconstruction Increase the Incidence of Secondary Pathology in the Knee? A Systematic Review and Meta-Analysis

Influence of time from injury to surgery on knee biomechanics during walking in patients with anterior cruciate ligament reconstruction

The pilot study aimed to determine whether the time from injury to surgery influences on postoperative knee biomechanics during walking in patients with anterior cruciate ligament reconstruction (ACLR). Thirty-two patients with unilateral ACLR (early, 10 patients; delayed, 22 patients) and 30 control subjects participated in this study. All examinations for patients with ACLR were performed preoperatively and at 12 months postoperatively and comprised passive knee joint laxity, knee muscle strength, and knee kinematics and kinetics during walking. At both time points, there were no significant differences in passive knee joint laxity and knee muscle strength between the early ACLR and delayed ACLR groups. Preoperatively, both the early ACLR and delayed ACLR patients exhibited significantly reduced knee extension movement from midstance to terminal stance compared to the control subjects. Moreover, the delayed ACLR patients exhibited significantly decreased peak external knee flexion moment compared to the control subjects. At 12 months postoperatively, the early ACLR patients showed significant improvement in knee extension movement from midstance to terminal stance compared to pre-ACLR, while the delayed ACLR patients did not show significant improvement in this knee extension movement. It can be concluded that early ACLR may be more beneficial to improve knee biomechanics during walking.

Effect of Age and Body Mass Index on Time to Advanced Imaging and Surgery in Young Athletes With Anterior Cruciate Ligament Injury

Background

In young athletes with anterior cruciate ligament (ACL) injury, increased times from injury to magnetic resonance imaging (MRI) and injury to surgery can lead to the accrual of new injuries over time.

Purpose

To determine the patient characteristics associated with differences in timing between injury, MRI, and surgery in young athletes with ACL tears.

Study Design

Case-control study; Level of evidence, 3.

Methods

We reviewed the electronic medical records of patients aged 13 to 25 years who underwent isolated primary ACL reconstruction between January 2017 and June 2020 at a single orthopaedic surgery department. The times from injury to MRI, MRI to surgery, and injury to surgery were documented. Patient demographic data (age, sex, body mass index [BMI], race and ethnicity, and insurance type) were recorded. Multivariable analysis was used to determine if any patient characteristic had a significant association with increased time to MRI or surgery.

Results

A total of 369 patients (mean age, 18.0 years; 56% female) were included. Both age and BMI were found to be significantly associated with timing of care while holding all other predictors constant. For every 1-year increase in patient age, time from injury to MRI increased by 9.6 days (95% CI, 1.8-17.4 days; P = .02), time from MRI to surgery increased by 7.4 days (95% CI, 4.4-10.5 days; P < .001), and time from injury to surgery increased by 17.0 days (95% CI, 8.4-25.6 days; P < .001). Compared with patients with normal BMI, overweight patients (BMI range, 25-29.9 kg/m2) had an MRI-to-surgery time that was on average 37.2 days (95% CI, 11.7-62.7 days; P < .004) longer and an injury to surgery time that was on average 71.8 days (95% CI, 0.5-143.0 days; P = .048) longer. Obese patients (BMI ≥30 kg/m2) did not demonstrate a significant relationship with the studied time intervals.

Conclusion

Increasing age and elevated BMI were found to be associated with increased time to MRI and surgical care in young athletes with ACL injuries.

IL-6 induces periostin production in human ACL remnants: a possible mechanism causing post-traumatic osteoarthritis

OBJECTIVE

Perostin (POSTN) and IL-6 consistently elevated after ACL injury, and ACL has been proposed as the major source of POSTN. However, there is a lack of evidence whether IL-6 induces ACL remnants to produce POSTN. This study aimed to investigate the effect of IL-6 on POSTN production in ACL fibroblasts, which may help us understand more about the mechanism of PTOA after ACL injury and ACL reconstruction.

METHODS

ACL remnants were harvested from 27 patients undergoing ACL reconstruction. Quantitative real-time polymerase chain reaction (PCR) was performed to examine the POSTN gene expression of ACL fibroblasts after treatment of different concentrations of IL-6. The POSTN protein production of ACL fibroblasts was determined using western blot analysis. The blockers of possible signaling pathways, including PI3K/Akt, Ras/MAPK, and JAK/STAT pathways, were added to test whether the effect of IL-6 on ACL fibroblast could be attenuated. ACL fibroblast and chondrocyte co-culture was carried out to determine the influence of ACL and IL-6 on chondrocytes.

RESULTS

Quantitative real-time PCR showed that IL-6 time-dependently and dose-dependently increased POSTN gene expression of ACL fibroblast. Western blot analysis also revealed that IL-6 dose-dependently induced POSTN protein production. Regarding the chronicity of ACL injury, the POSTN protein production was comparable between ACL remnants which were derived within 3 months of injury and at least 6 months after injury. PI3K/Akt blockers could attenuate the effect of IL-6 on ACL remnants, whereas Ras/MAPK and JAK/STAT did not decrease POSTN production. The coexistence of ACL and IL-6 induced more MMP-13 and ADAMTS-4 by chondrocytes.

CONCLUSIONS

IL-6 induced ACL remnants to produce POSTN. This effect could be attenuated by the PI3K/Akt blocker. Coexistence of IL-6 and ACL remnants may accelerate post-traumatic arthritis.

Efficacy and safety of early versus delayed reconstruction for anterior cruciate ligament injuries: A systematic review and meta-analysis

OBJECTIVE

To critically evaluate the efficacy and safety of early versus delayed anterior cruciate ligament reconstruction (ACLR) for anterior cruciate ligament (ACL) injuries based on the different cut-off values of the timing of operation.

METHODS

PubMed, Medline, Embase, Cochrane library, China National Knowledge Infrastructure, Chinese Biomedical Literature, and Wanfang Digital Periodical database were searched from inception to November 2022 without language restrictions. Randomized controlled trials (RCTs) and cohort studies (CSs) comparing early ACLR with delayed ACLR for ACL injuries were included.

RESULTS

Twenty-four studies (10 RCTs and 14 CSs) were included. According to the information from included studies, 3 weeks, 4 weeks, 6 weeks, 6 months, and 12 months after ACL injuries were considered as the cut-off values of early and delayed ACLR. When 4 weeks were considered as the cut-off value, early ACLR could significantly improve Lysholm score, IKDC score and VAS score at 6 and 12 months postoperatively and decrease the incidence of adverse events compared with delayed ACLR (P < 0.05). However, no statistically significant difference in positive rate of Lachman test and incidence of meniscus injuries and chondral lesions between the two groups when 3 weeks, 6 weeks, 6 months or 12 months after ACL injuries were considered as the cut-off values of early and delayed ACLR (P > 0.05).

CONCLUSION

The present study suggests that early ACLR, especially conducted within 3-4 weeks after ACL injuries, may be more effective for improving knee function and relieving pain compared with delayed ACLR. More high-quality RCTs are warranted.

Effect of Delayed Anterior Cruciate Ligament Reconstruction on Repair of Concomitant Medial Meniscus Tears in Young Athletes

BACKGROUND

Delayed anterior cruciate ligament (ACL) reconstruction (ACLR) is associated with an increased risk of meniscal injury. Limited data are available regarding the relationship between surgical delay and meniscal repairability in the setting of ACLR in young patients.

PURPOSE

To determine whether time from ACL injury to primary ACLR was associated with the incidence of medial and/or lateral meniscal repair in young athletes who underwent meniscal treatment at the time of ACLR.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Records were retrospectively reviewed for patients aged 13 to 25 years who underwent primary ACLR between January 2017 and June 2020 by surgeons from a single academic orthopaedic surgery department. Demographic data were collected, and operative reports were reviewed to document all concomitant pathologies and procedures. Univariable and multivariable logistic regression analyses were used to determine factors associated with meniscal repair, including time elapsed from ACL injury to surgery.

RESULTS

Concomitant meniscal tears were identified and treated in 243 of 427 patients; their mean age was 17.9 ± 3.3 years, and approximately half (47.7%) of patients were female. There were 144 (59.3%) medial tears treated and 164 (67.5%) lateral tears treated; 65 (26.7%) patients had both medial and lateral tears treated. Median time from ACL injury to ACLR was 2.4 months (interquartile range, 1.4-4.7 months). Adjusted univariate analysis showed a statistically significant correlation between medial meniscal repair and time to surgery, with a 7% decreased incidence of medial meniscal repair per month elapsed between injury and surgery (odds ratio, 0.93 per month; 95% CI, 0.89-0.98; P = .006). No similar relationship was found between lateral meniscal repair and time to surgery (odds ratio, 1.02; 95% CI, 0.99-1.06; P = .24).

CONCLUSION

In the setting of concomitant ACL and meniscal injuries, surgical delay decreased the incidence of medial meniscal repair in young athletes by 7% per month from time of injury.

Early ACLR and Risk and Timing of Secondary Meniscal Injury Compared With Delayed ACLR or Nonoperative Treatment: A Time-to-Event Analysis Using Machine Learning

BACKGROUND

Surgical and nonoperative management of anterior cruciate ligament (ACL) injuries seek to mitigate the risk of knee instability and secondary meniscal injury. However, the associated risk and timing of secondary meniscal tears have not been completely elucidated.

PURPOSE

To compare risk and timing of secondary meniscal injury between patients receiving nonoperative management, delayed ACL reconstruction (ACLR), and early ACLR using a machine learning survival analysis.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A geographic database was used to identify and review records of patients with a diagnosis of ACL rupture between 1990 and 2016 with minimum 2-year follow-up. Patients undergoing ACLR were matched 1:1 with nonoperatively treated controls. Rate and time to secondary meniscal tear were compared using random survival forest algorithms; independent models were developed and internally validated for predicting injury-free duration in both cohorts. Performance was measured using out-of-bag c-statistic, calibration, and Brier score. Model interpretability was enhanced using global variable importance and partial dependence curves.

RESULTS

The study included 1369 patients who underwent ACLR and 294 patients who had nonoperative treatment. After matching, no significant differences in rates of secondary meniscal tear were found (P = .09); subgroup analysis revealed the shortest periods of meniscal survival in patients undergoing delayed ACLR. The random survival forest algorithm achieved excellent predictive performance for the ACLR cohort, with an out-of-bag c-statistic of 0.80 and a Brier score of 0.11. Significant variables for risk of meniscal tear for the ACLR cohort included time to return to sports or activity ≤350 days, time to surgery ≥50 days, age at injury ≤40 years, and high-impact or rotational landing sports, whereas those in the nonoperative cohort model included time to RTS ≤200 days, visual analog scale pain score >3 at consultation, hypermobility, and noncontact sports.

CONCLUSION

Delayed ACLR demonstrated the greatest long-term risk of meniscal injury compared with nonoperative treatment or early ACLR. Risk factors for decreased meniscal survival after ACLR included increased time to surgery, shorter time to return to sports or activity, older age at injury, and involvement in high-impact or rotational landing sports. Pending careful external validation, these models may be deployed in the clinical space to provide real-time insights and enhance decision making.

Acute and subacute anterior cruciate ligament reconstructions are associated with a higher risk of revision and reoperation

PURPOSE

(1) Report concomitant cartilage and meniscal injury at the time of anterior cruciate ligament reconstruction (ACLR), (2) evaluate the risk of aseptic revision ACLR during follow-up, and (3) evaluate the risk of aseptic ipsilateral reoperation during follow-up.

METHODS

Using a United States integrated healthcare system's ACLR registry, patients who underwent primary isolated ACLR were identified (2010-2018). Multivariable Cox proportional-hazards regression was used to evaluate the risk of aseptic revision, with a secondary outcome evaluating ipsilateral aseptic reoperation. Outcomes were evaluated by time from injury to ACLR: acute (< 3 weeks), subacute (3 weeks-3 months), delayed (3-9 months), and chronic (≥ 9 months).

RESULTS

The final sample included 270 acute (< 3 weeks), 5971 subacute (3 weeks-3 months), 5959 delayed (3-9 months), and 3595 chronic (≥ 9 months) ACLR. Medial meniscus [55.4% (1990/3595 chronic) vs 38.9% (105/270 acute)] and chondral injuries [40.0% (1437/3595 chronic) vs 24.8% (67/270 acute)] at the time of ACLR were more common in the chronic versus acute groups. The crude 6-year revision rate was 12.9% for acute ACLR, 7.0% for subacute, 5.1% for delayed, and 4.4% for chronic ACLR; reoperation rates a 6-year follow-up was 15.0% for acute ACLR, 9.6% for subacute, 6.4% for delayed, and 8.1% for chronic ACLR. After adjustment for covariates, acute and subacute ACLR had higher risks for aseptic revision (acute HR 1.70, 95% CI 1.07-2.72, p = 0.026; subacute HR 1.25, 95% CI 1.01-1.55, p = 0.040) and aseptic reoperation (acute HR 2.04, 95% CI 1.43-2.91, p < 0.001; subacute HR 1.31, 95% CI 1.11-1.54, p = 0.002) when compared to chronic ACLR.

CONCLUSIONS

In this cohort study, while more meniscal and chondral injuries were reported for ACLR performed ≥ 9 months after the date of injury, a lower risk of revision and reoperation was observed following chronic ACLR relative to patients undergoing surgery in acute or subacute fashions.

Does Surgery for Cruciate Ligament and Meniscus Injury Increase the Risk of Comorbidities at 2 Years in the Military System?

This study aims to determine whether surgery for cruciate ligament (anterior or posterior) or meniscus injury increased risks of subsequent comorbidities in beneficiaries of the Military Health System. The study was a retrospective case-control design in which individuals with cruciate or meniscus injuries were divided into two groups (surgery or none). Data were pulled 12 months prior and 24 months following each respective event and presence of comorbidities were compared between the two groups. Bivariate analyses and logistic regression were used to determine if surgery increased the odds of comorbidities. Participants included 1,686 with a cruciate ligament injury (30.1% treated surgically) and 13,146 with a meniscus injury (44.4% treated surgically). Bivariate comparisons of surgery versus nonsurgical treatment found multiple significant differences. After adjusting for covariates, a significant (p < 0.05) protective effect was seen only for meniscus surgery for concussion, insomnia, other mental health disorders, depression, and substance abuse. Surgery had no increased/decreased risk of comorbidities for cruciate ligament injuries. For meniscus injuries, surgery demonstrated a protective effect for six of the comorbidities we assessed. The treatment approach (surgery vs. nonsurgical) did not change the risk of comorbidities in those with a cruciate ligament injury. It is noteworthy that three of the six comorbidities involved mental health disorders. Although the study design does not allow for determination of causation, these findings should compel future prospective study designs that could confirm these findings.

[Consequences of anterior cruciate ligament rupture: a systematic umbrella review]

INTRODUCTION

 The treatment of an anterior cruciate ligament rupture is still controversial. In particular, this applies to the question of conservative versus surgical treatment. The answer to this question is often based on consequential damage such as the development of posttraumatic osteoarthritis, secondary damage to the meniscus or cartilage, and participation in sports. If there are significant differences in these parameters between the individual treatment options, the results will be of great importance for the development of evidence-based treatment pathways. Therefore, the aim of this work was to evaluate the development of knee osteoarthritis after rupture of the anterior cruciate ligament and the corresponding treatment (conservative or surgical).

MATERIAL AND METHODS

 To answer the above question, a systematic literature search was conducted in Medline via Pubmed, the Cochrane Library and in CINAHL. Only systematic reviews with a minimum follow-up period of 10 years were included. The search was conducted in January 2020 and updated in January 2021. Investigated cohorts included patients with a rupture of the anterior cruciate ligament who had undergone either conservative or surgical treatment. Osteoarthritis was diagnosed either radiologically (recognized scores) or clinically (pain and impaired function). Appropriate reviews were qualitatively evaluated using the AMSTAR-2 questionnaire.

RESULTS

 The literature research initially identified n = 42 reviews from which 14 reviews were included. After full-text review and qualitative evaluation, only n = 2 systematic reviews remained for evaluation. The results of both papers show imprecise data with a high variability. However, it can be assumed with high probability that the development of osteoarthritis of the knee is increased after a rupture of the anterior cruciate ligament. There is no evidence that the incidence of joint degeneration may be reduced by reconstruction of the anterior cruciate ligament, nor is there a difference when comparing conservative and surgical treatment directly.

CONCLUSION

 Patients with an anterior cruciate ligament rupture are likely to be at a greater risk of developing progressive joint degeneration. A protective effect of cruciate ligament surgery has not been found in the evaluated studies. A general argument in favour of cruciate ligament surgery aiming to achieve a protective effect on hyaline articular cartilage seems obsolete based on the results and should therefore not be used in patient education in the future.

Evidence for the effects of prehabilitation before ACL-reconstruction on return to sport-related and self-reported knee function: A systematic review

Study design

Systematic review.

Background and objectives

Preoperative neuromuscular function is predictive for knee function and return to sports (RTS) after reconstruction of the anterior cruciate ligament (ACL). The aim of this review was to examine the potential benefits of prehabilitation on pre-/postoperative objective, self-reported and RTS-specific outcomes.

Methods

A systematic search was conducted within three databases. From the 1.071 studies screened, two randomized control trials (RCTs), two control trials (CTs) and two cohort studies (CS) met the inclusion criteria. Methodological quality rating adopted the PEDro- (RCT, CT) or Newcastle-Ottawa-Scale (CS).

Results and conclusions

Methodological quality of the included studies was moderate (PEDro score: 6.5 ± 1.7; range 4 to 9). Two studies reported higher increases of the maximal quadriceps torque from baseline to pre-reconstruction: one study in the limb symmetry index (LSI), and one in both legs of the prehabilitation group compared to the controls. At 12-weeks post-reconstruction, one study (from two) indicated that the prehabilitation group had a lesser post-operative decline in the single-leg-hop for distance LSI (clinically meaningful). Similar findings were found in terms of quadriceps strength LSI (one study). At both pre-reconstruction (three studies) and two-year post-surgery (two studies), the prehabilitation groups reached significantly higher self-reported knee function (clinically meaningful) than the controls. RTS tended to be faster (one study). At two years post-surgery, RTS rates (one study) were higher in the prehabilitation groups. The results provide evidence for the relevance of prehabilitation prior to ACL-reconstruction to improve neuromuscular and self-reported knee function as well as RTS. More high quality confirmatory RCTs are warranted.

Registration number

PROSPERO 2017: CRD42017065491.