Objectifying the Pivot Shift Test

Young men undergoing anterior cruciate ligament reconstruction with patellar tendon autograft and anteromedial drilling outperform at 5- to 10-year follow-up in terms of graft stability and activity levels compared to those undergoing reconstruction with hamstring autograft and transtibial drilling

OBJECTIVE

To compare 5- to 10-year outcomes of anterior cruciate ligament (ACL) reconstruction in young men performed with bone-patellar tendon bone (BPTB) autograft and anteromedial portal to reconstruction with hamstring autograft and transtibial technique. It was hypothesised that in young adult men, at 5- to 10-year follow-up, superior restoration of knee laxity and activity levels would be demonstrated using BPTB autograft and anteromedial portal technique.

METHODS

Ninety-four men who had ACL reconstruction with BPTB autograft and anteromedial portal were eligible for comparison to 106 men who had reconstruction with hamstring autograft and transtibial technique. Inclusion criteria were: (1) age 18-35 years, (2) ACL tear caused by sports trauma only, (3) no concomitant ligament reconstruction and (4) 5- to 10-year follow-up. Outcome measures compared between the two groups included Lachman and pivot shift tests, KT side-to-side difference, Tegner and Marx scores, International Knee Documentation Committee (IKDC)-subjective score, Knee Osteoarthritis Outcome Scale (KOOS), Short Form (SF)-36, and single hop test for distance. P value ​< ​0.05 indicated statistical significance.

RESULTS

Forty-five patients with BPTB and 55 patients with hamstring ACL reconstruction were available for in-person assessment at 5-10 years after surgery. Outcomes in the BPTB group compared to the hamstring group showed KT difference 1.4 ​± ​1.9 mm vs. 2.8 ​± ​2.3 mm (p ​< ​0.01), pivot shift grade 2-3 in 4% vs. 34% (p ​< ​0.01), return to preinjury Tegner level in 51% vs. 36% (p ​= 0.1) and to preinjury Marx score in 29% vs. 11% (p ​= 0.02), and IKDC-subjective 88 ​± ​10 vs. 82 ​± ​13 vs (p ​< ​0.01), respectively. Statistically significant inter-relationships were found between KT side-to-side difference and the Tegner, Marx and IKDC-subjective scores at follow-up (r ​= ​-0.314, p ​< ​0.01; r ​= ​-0.263, p ​< ​0.01; r ​= ​-0.218, p ​= ​0.03, respectively).

CONCLUSION

Young men undergoing ACL reconstruction with patellar tendon autograft and anteromedial drilling outperform at 5- to 10-year follow-up in terms of graft stability and activity levels compared to young men undergoing reconstruction with hamstring autograft and transtibial drilling.

LEVEL OF EVIDENCE

III (Retrospective cross-sectional comparative study).

Combining an Anterolateral Complex Procedure With Anterior Cruciate Ligament Reconstruction Reduces the Graft Reinjury Rate and Improves Clinical Outcomes: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND

Anterior cruciate ligament (ACL) reconstruction (ACLR) is a well-established surgical procedure, but it may not always restore complete rotational knee stability. Interest is increasing in anterolateral complex (ALC) procedures, lateral extra-articular tenodesis (LET) and anterolateral ligament reconstruction (ALLR), in association with ACLR to overcome this problem. The better ALC procedure, LET or ALLR, remains controversial to date.

PURPOSE

To analyze the patient-reported outcome measures and ACL reinjury rate after ACLR with an ALC procedure compared with after isolated ACLR, as well as to analyze the clinical results and graft failure rate of the LET group versus the ALLR group.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 2.

METHODS

A PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) flowchart was used to conduct a comprehensive search of 5 databases: Scopus, MEDLINE, Embase, PubMed, and the Cochrane Database of Systematic Reviews. Only randomized controlled trials were included. Eligible articles were classified according to the levels of evidence of the Oxford Centre for Evidence-Based Medicine. A methodological quality assessment of randomized controlled trials was performed using the Risk of Bias 2 tool. The present systematic review and meta-analysis was registered on PROSPERO.

RESULTS

A total of 14 clinical trials were included in the final analysis, with 1830 patients. Isolated ACLR or a combined procedure with LET or ALLR was performed, with several characteristics described, including the surgical technique, additional torn knee structures and their management, graft failure, complications, clinical outcomes, clinical and instrumental examinations to assess knee stability, and postoperative protocols. Regarding clinical outcomes, pivot-shift tests and reduced graft failure, a significant difference was found in the superiority of the combined ACLR associated with the ALC procedure compared with an isolated ACLR (P < .05). No statistically significant difference was found between the 2 ALC procedures.

CONCLUSION

This systematic review and meta-analysis reported on the importance of combined ACLR and ALC procedures in patients with a high-grade rotational laxity, as both procedures, LET or ALLR, without superiority of one over the other, are associated with improved pivot-shift tests, patient-reported outcome measures, and reduced graft failure rates.

Dynamic radiostereometry can objectively quantify the kinematic laxity patterns and rotation instability of the knee during a pivot-shift test

PURPOSE

The pivot-shift test is used to clinically assess knee instability in patients with anterior cruciate ligament (ACL) lesions; however, it has low interobserver reliability. Dynamic radiostereometry (dRSA) is a highly precise and noninvasive method for the objective evaluation of joint kinematics. The purpose of this study was to quantify precise knee kinematics during a pivot-shift test using dRSA imaging.

METHOD

Eight human donor legs, including hemipelvises, were evaluated. Arthroscopic intervention was performed inducing ligament lesions in the ACL, and anterolateral ligament (ALL) section was performed as a capsular incision. The pivot-shift test was recorded with dRSA on knees with intact ligaments, ACL-deficient and ACL + ALL-deficient knees.

RESULTS

A pivot-shift pattern was identifiable after ligament lesion, as a change in tibial posterior drawer velocity from 7.8 mm/s (95% CI: 3.7; 11.9) in ligament intact knees to 30.4 mm/s (95% CI 23.0; 38.8) after ACL lesion to 35.1 mm/s (95% CI 23.4; 46.7) after combined ACL-ALL lesion. The anterior-posterior drawer excursion increased from 2.8 mm (95% CI 2.1; 3.4) in ligament intact knees to 7.2 mm (95% CI 5.5; 8.9) after ACL lesion to 7.6 mm (95% CI 5.5; 9.8) after combined lesion. A statistically significant increase in tibial external rotation towards the end of the pivot-shift motion was observed when progressing from intact to ACL + ALL-deficient knees (p < 0.023).

CONCLUSION

This experimental study demonstrates the feasibility of dRSA to objectively quantify the kinematic laxity patterns of the knee during the pivot-shift test. The dynamic parameters obtained through dRSA revealed the kinematic changes from ACL to combined ACL-ALL ligament lesion.

LEVEL OF EVIDENCE

Not applicable.

Anterior Cruciate Ligament Rupture Combined with Complete Radial Tear of the Posterior Horn of the Lateral Meniscus: Suture or Resection?

Anterior cruciate ligament (ACL) rupture often presents with a tear of the posterior horn of the lateral meniscus. There is no clear preference between ACL reconstruction with suture and resection of the meniscus. We aimed to compare the clinical efficacy of ACL reconstruction with suture versus resection in patients presenting with arthroscopic ACL rupture and radial complete tear of the posterior corner of the lateral meniscus. We retrospectively analyzed 157 patients with ACL rupture and complete radial tear of the posterior horn of the lateral meniscus. Between May 2010 and April 2015, 86 of 157 patients underwent ACL reconstruction and meniscus suture (study group, 54.78%) and 71 of 157 patients underwent ACL reconstruction and meniscus resection (control group, 45.22%) in our department. All patients were monitored over the 12 to 72-month follow-up period. The primary evaluation indices were the Lysholm scores, the International Knee Documentation Committee (IKDC) scores, pivot shift test, the Barret criteria, and magnetic resonance imaging (MRI) findings of meniscal healing. The majority of 157 patients were relatively young men (29.64 ± 7.79 years) with low body mass index (BMI) (23.79 ± 2.74). The postoperative Lysholm and IKDC scores of the two groups were significantly improved over the corresponding preoperative scores (p < 0.05). The clinical results and excellent and good rates were significantly better for the study group than for the control group (both, p < 0.05). MRI showed that the meniscal healed rate of the study group was 96.51%. There was no significant difference in BMI between subgroups for any functional outcome. For patients with ACL rupture and complete radial tear of the posterior horn of the lateral meniscus, ACL reconstruction and both simultaneous suture and resection of the posterior horn of the lateral meniscus were found to be safe and effective. There was no association between outcomes and BMI. However, the former was associated with a superior long-term clinical effect and may restore the integrity of the meniscus and is particularly recommended for young patients.

Platelet-rich plasma augmentation in anterior cruciate ligament reconstruction: Evidence is still too scattered. A scoping review of randomised controlled trials

PURPOSE

Platelet-rich plasma (PRP) augmentation has been proposed to improve the results of anterior cruciate ligament reconstruction (ACLR). The present study aims to quantify the available evidence to support the use of PRP as biological augmentation in ACLR surgery.

METHODS

A systematic literature search was conducted on the PubMed, Cochrane, Web of Science and Embase databases on 10 March 2023. Inclusion criteria were randomised controlled trials (RCTs), written in English, addressing PRP augmentation in ACLR surgery, with no time limitation. A scoping review was performed to map the body of literature by examining the evidence related to specific aspects of patients' treatment and evaluation. Risk of bias evaluation was performed with the Cochrane risk-of-bias tool for randomised trials Version 2 (RoB 2), while the quality assessment was performed with the use of the Coleman Score.

RESULTS

Out of 983 articles retrieved, 23 RCTs on 943 knees were included in this scoping review. PRP was administered in a liquid form in nine studies and clotted in 11 studies, while in three studies both liquid and clotted PRP were used. Hamstring auto/allografts were used in 14 studies, patellar tendon auto/allografts were used in eight studies and one study described ACLR with peroneus longus allografts. The map of the evidence documented high heterogeneity also in terms of surgical technique, objective and subjective outcome measures and radiological assessment, as well as follow-up times ranging from 1 day to 2 years, with virtually no overlapping data among studies neither in terms of treatments nor evaluations. Risk of bias evaluation showed an overall low quality of the included studies.

CONCLUSIONS

The available literature addressing PRP augmentation in ACLR is largely scattered. PRP was produced and applied following different procedures, and high variability was detected across the included studies for every aspect of ACLR surgery and evaluation. Currently, a meaningful comparison of the available studies is not possible as the quantification of the literature results is biased by their heterogeneity. Future studies should provide more standardisation to investigate the benefits of biological augmentation in ACL surgery and confirm the promising yet weak evidence of PRP potential as well as the most suitable application modality, before routine use in clinical practice.

LEVEL OF EVIDENCE

Levels I and II, scoping review.

Study on the use of 3D printed guides in the individualized reconstruction of the anterior cruciate ligament

OBJECTIVE

Evaluation of the accuracy and effectiveness of 3D printed guides to assist femoral tunnel preparation in individualised reconstruction of the anterior cruciate ligament.

METHODS

Sixty patients who attended the Affiliated Hospital of Binzhou Medical College for autologous hamstring single bundle reconstruction of the anterior cruciate ligament from October 2018 to October 2020 were selected and randomly divided into two groups, including 31 cases in the 3D printing group (14 males and 17 females, mean age 41.94 ± 10.15 years) and 29 cases in the control group (13 males and 16 females, mean age 37.76 ± 10.34 years). Patients in both groups were assessed for intraoperative femoral tunnel accuracy, the number of intraoperative positioning and the time taken to prepare the femoral tunnel, the length of the anteromedial approach incision, the pre-planned bone tunnel length and intraoperative bone tunnel length in the 3D printed group, IKDC score and Lysholm score preoperatively and at 3, 6 and 12 months postoperatively, the Lachman、pivot-shift test preoperatively and at 6 months postoperatively, gait analysis to assess internal and external rotation in flexion of the knee at 12 months postoperatively and postoperative complications in both groups.

RESULTS

There was no statistical difference in functional knee scores and anteromedial approach incision length between the 3D printed and control groups (p > 0.05), while there was a statistical difference in the accuracy of tunnel positioning, the time taken to prepare the femoral bone tunnel and the degree of external rotation of the knee in flexion between the two groups (p < 0.05). There was no statistical difference between the preoperative planning of the bone tunnel length and the intraoperative bone tunnel length (p > 0.05).

COMPLICATIONS

One case in the 3D printing group developed intermuscular vein thrombosis in the affected lower limb after surgery, which disappeared after treatment, while three cases in the control group developed intermuscular vein thrombosis in the affected lower limb. No complications such as bone tunnel rupture, deep vein thrombosis in the lower limb and infection occurred in either group.

CONCLUSION

3D printed guides assisted with individualized ACL reconstruction may improve the accuracy of femoral tunnel positioning, which is safe and effective, while reducing the operative time and the number of intraoperative positioning, without increasing the length of incision, and may obtain higher functional scores and rotational stability of the knee joint, which is in line with the concept of individualized ACL reconstruction.

Factors Associated With Residual Pivot Shift After ACL Reconstruction: A Quantitative Evaluation of the Pivot-Shift Test Preoperatively and at Minimum 12-Month Follow-up

Background

Postoperative residual rotatory laxity remains despite improvement in surgical techniques for anterior cruciate ligament (ACL) reconstruction (ACLR).

Purpose

To evaluate factors associated with residual pivot shift after ACLR by quantitative measurement of the pivot shift before and after surgery.

Study Design

Case-control study; Level of evidence, 3.

Methods

A total of 97 patients who underwent primary double-bundle ACLR between June 2016 and March 2021 and underwent surgery to remove staples, with at least 12 months of follow-up evaluation, were enrolled. Quantitative measurements were performed under general anesthesia immediately before ACLR (preoperatively), after temporary fixation of the ACL graft (intraoperatively), and immediately before staple removal (postoperatively). The laxity of pivot shift was assessed using inertial sensors to measure acceleration and external rotational angular velocity (ERAV). Descriptive data were assessed for associations with postoperative acceleration and ERAV in a univariate analysis. A multiple linear regression analysis was performed to identify factors associated with postoperative acceleration and ERAV.

Results

Anterior tibial translation, acceleration, and ERAV increased from intra- to postoperatively (P < .05). Factors significantly associated with postoperative acceleration were age (β = -0.238; P = .021), lateral posterior tibial slope (PTS) (β = 0.194; P = .048), and preoperative acceleration (β = 0.261; P = .008). Factors significantly affecting postoperative ERAV were age (β = -0.222; P = .029), ramp lesions (β = 0.212; P = .027), and preoperative ERAV (β = 0.323; P = .001).

Conclusion

Greater preoperative laxity in the pivot shift was the factor having the most significant association with residual pivot shift after ACLR using quantitative measurements under general anesthesia. Younger age, higher lateral PTS, and concomitant ramp lesions were significant predictors of residual pivot shift. These findings can help pre- and intraoperative decision-making regarding whether an anterolateral structure augmentation should be added.

Though five-strand hamstring autografts demonstrate greater graft diameter, postoperative outcomes are equivocal to four-strand hamstring autograft preparations: a systematic review and meta-analysis of level I and II studies

PURPOSE

To compare graft dimensions, functional outcomes, and failure rates following anterior cruciate ligament reconstruction (ACLR) with either five-strand or four-strand hamstring autograft options.

METHODS

Three databases (MEDLINE, PubMed, and EMBASE) were searched from inception to 22 April 2023 for level I and II studies comparing five- and four-strand hamstring autografts in ACLR. The authors adhered to the PRISMA and R-AMSTAR guidelines as well as the Cochrane Handbook for Systematic Reviews of Interventions. Data on demographics, surgical details and rehabilitation, graft diameter, patient-reported outcome measures (PROMs), and rates of positive Lachman test, positive pivot shift test, and graft rupture were extracted. PROMs included Knee Osteoarthritis and Outcome Score (KOOS) subscales, Lysholm, and International Knee Documentation Committee (IKDC).

RESULTS

One randomized controlled trial (RCT) and four prospective cohort studies with 572 patients were included. Graft diameters were larger in the five-strand group with a mean difference of 0.93 mm (95% CI 0.61 to 1.25, p < 0.001, I2 = 66%). The five-strand group reported statistically higher KOOS ADL subscale and Lysholm scores with a mean difference of 4.85 (95% CI 0.14 to 9.56, p = 0.04, I2 = 19%) and 3.01 (95% CI 0.48 to 5.53, p = 0.02, I2 = 0%), respectively. There were no differences in KOOS symptoms, pain, quality of life, or sports subscales, or IKDC scores. There were no differences in rates of positive Lachman test, positive pivot shift test, or graft rupture with pooled odds ratios of 0.62 (95% CI 0.13 to 2.91, n.s., I2 = 80%), 0.94 (95% CI 0.51 to 1.75, n.s., I2 = 31%), and 2.13 (95% CI 0.38 to 12.06, n.s., I2 = 0%), respectively.

CONCLUSIONS

Although five-stranded hamstring autografts had significantly larger graft diameters compared to four-stranded grafts with a mean difference of 0.93 mm, similar graft rupture rates and clinical laxity assessments were identified following ACLR. While some PROMs were statistically superior in the five-stranded hamstring groups, the threshold for the minimal clinical important difference was not reached indicating similar clinical outcomes overall.

LEVEL OF EVIDENCE

Level II.

What it takes to have a high-grade pivot shift-focus on bony morphology

PURPOSE

Variations in femoral and tibial bony morphology have been associated with higher clinical grading and increased quantitative tibial translation, but not tibial acceleration, during the pivot shift test following anterior cruciate ligament (ACL) injury. The purpose of this study was to determine the impact of femoral and tibial bony morphology, including a measurement influenced by both parameters (the Lateral Tibiofemoral Articular Distance (LTAD)), on the degree of quantitative tibial acceleration during the pivot shift test and rates of future ACL injury.

METHODS

All patients who underwent primary ACL reconstruction from 2014 to 2019 by a senior orthopedic surgeon with available quantitative tibial acceleration data were retrospectively reviewed. All patients underwent a pivot shift examination under anesthesia with a triaxial accelerometer. Measurements of femoral and tibial bony morphology were performed by two fellowship-trained orthopedic surgeons using preoperative magnetic resonance imaging and lateral radiographs.

RESULTS

Fifty-one patients were included at a mean follow-up of 4.4 years. The mean quantitative tibial acceleration during the pivot shift was 13.8 m/s2 (range: 4.9-52.0 m/s2). A larger Posterior Condylar Offset Ratio (r = 0.30, p = 0.045), smaller medial-to-lateral width of the medial tibial plateau (r = - 0.29, p = 0.041), lateral tibial plateau (r = - 0.28, p = 0.042), and lateral femoral condyle (r = - 0.29, p = 0.037), and a decreased LTAD (r = - 0.53, p < 0.001) significantly correlated with increased tibial acceleration during the pivot shift. Linear regression analysis demonstrated an increase in tibial acceleration of 1.24 m/s2 for every 1 mm decrease in LTAD. Nine patients (17.6%) sustained ipsilateral graft rupture and 10 patients (19.6%) sustained contralateral ACL rupture. No morphologic measurements were associated with rates of future ACL injury.

CONCLUSION

Increased convexity and smaller bony morphology of the lateral femur and tibia were significantly associated with increased tibial acceleration during the pivot shift. Additionally, a measurement, termed the LTAD, was found to have the strongest association with increased tibial acceleration. Based on the results of this study, surgeons can utilize these measurements to preoperatively identify patients at risk of increased rotatory knee instability.

LEVEL OF EVIDENCE

Level IV.

Bone-patellar tendon-bone versus two- and four-strand hamstring tendon autografts for ACL reconstruction in young adults: a Bayesian network meta-analysis

Bone-patellar tendon-bone (BPTB), two- and four-strand hamstring tendon (4SHT and 2SHT, respectively) are the most common autografts used for anterior cruciate ligament (ACL) reconstruction. The present study compared BPTB, 2SHT, and 4SHT for ACL reconstruction in terms of joint laxity, patient reported outcome measures (PROMs), rate of failure and anterior knee pain (AKP). The time to return to sport and the peak torque between the autografts were also compared. Finally, prognostic factors leading to worse outcomes were also investigated. It was hypothesized that all grafts yield similar proprieties in terms of joint laxity, patient reported outcome measures (PROMs) and rate of failure, but that the BPTB autograft causes a greater rate of anterior knee pain (AKP). The literature search was conducted. All clinical trials comparing BTPB and/or 2SHT, and/or 4SHT were accessed. Grafts other than BTPB and/or 4SHT and/or 2SHT were not considered. Articles reporting outcomes of allografts or synthetic grafts were not eligible, nor were those concerning revision settings. Articles reporting ACL reconstruction in patients with multi-ligament damage were also not eligible. Data from 95,575 procedures were retrieved. The median length of follow-up was 36 months. The median age of the patients was 27.5 years. With regard to joint laxity, similarity was found in terms of Lachman and Pivot shift tests between all three autografts. The BPTB demonstrated the greatest stability in terms of instrumental laxity. BPTB demonstrated the greatest PROMs. BPTB demonstrated the greatest rate of AKP, while AKP in 2SHT and 4SHT was similar. Concerning failure, statistically significant inconsistency was found (P = 0.008). The 4SHT demonstrated the quickest return to sport, followed by BPTB, and 2SHT. There was evidence of a negative association between the time span between injury to surgery, Lysholm score (P = 0.04), and Tegner scale (P = 0.04). Furthermore, there was evidence of a weak positive association between the time span between injury to surgery and return to sport (P = 0.01). BPTB may result in lower joint laxity, greater PROMs, and greater peak flexion torque compared to 2SHT and 4SHT autografts. On the other hand, BPTB reported the lowest peak extension torque and the greatest rate of AKP. Finally, a longer time span between injury and surgery negatively influences outcome.

Navigation in anterior cruciate ligament reconstruction: State of the art

Computer navigation (CN) for anterior cruciate ligament (ACL) surgery has been used mainly for two purposes: to enhance the accuracy of tunnel position and to evaluate the kinematics of the ACL reconstruction (ACLR) and the stability achieved by different surgical techniques. Many studies have shown that navigation may improve the accuracy of anatomical tunnel orientation and position during ACL reconstructive surgery compared with normal arthroscopic tunnel placement, especially regarding the femoral side. At the same time, it has become the gold-standard method for intraoperative knee kinematic assessment, as it permits a quantitative multidirectional knee joint laxity evaluation. CN in ACL surgery has been associated with diverse problems. First, in most optic systems additional skin incisions and drill holes in the femoral bone are required for fixation of a reference frame to the femur. Second, additional radiation exposure and extra medical cost to the patient for preoperative planning are usually needed. Third, CN, due to additional steps, has more opportunities for error during preoperative planning, intraoperative registration, and operation. Fourth, soft tissues, including the skin and subcutaneous tissues, are usually not considered during the preoperative planning, which can be a problem for kinematic and stability assessment. Many studies have concluded that ACLR using a CN system is more expensive than conventional surgery, it adds extra time to the surgery and it is not mitigated by better clinical outcomes. This, combined with costs and invasiveness, has limited the use of CN to research-related cases. Future technology should prioritize less invasive intra-operative surgical navigation.

Preoperative quantitative pivot shift does not correlate with in vivo kinematics following ACL reconstruction with or without lateral extraarticular tenodesis

PURPOSE

Quantitative pivot shift (QPS) testing using PIVOT technology can detect high- and low-grade rotatory knee instability following anterior cruciate ligament injury or reconstruction (ACLR). The aim of this project was to determine if preoperative QPS correlates with postoperative knee kinematics in the operative and contralateral, healthy extremity following ACLR with or without lateral extraarticular tenodesis (LET) using a highly precise in vivo analysis system. A positive correlation between preoperative QPS and postoperative tibial translation and rotation following ACLR with or without LET in the operative and healthy, contralateral extremity was hypothesized.

METHODS

Twenty patients with ACL injury and high-grade rotatory knee instability were randomized to undergo anatomic ACLR with or without LET as part of a prospective randomized trial. At 6 and 12 months postoperatively, in vivo kinematic data were collected using dynamic biplanar radiography superimposed with high-resolution computed tomography scans of patients' knees during downhill running. Total anterior-posterior (AP) tibial translation and internal-external tibial rotation were measured during the gait cycle. Spearman's rho was calculated for preoperative QPS and postoperative kinematics.

RESULTS

In the contralateral, healthy extremity, a significant positive correlation was seen between preoperative QPS and total AP tibial translation at 12 months postoperatively (r_s = 0.6, p < 0.05). There were no additional significant correlations observed between preoperative QPS and postoperative knee kinematics at 6 and 12 months postoperatively in the operative and contralateral, healthy extremity for combined isolated ACLR and ACLR with LET patients as well as isolated ACLR patients or ACLR with LET patients analyzed separately.

DISCUSSION

The main finding of this study was that there was a significant positive correlation between preoperative QPS and total AP tibial translation at 12 months postoperatively in the contralateral, healthy extremity. There were no significant correlations between preoperative QPS and postoperative in vivo kinematics at 6 and 12 months following ACLR with or without LET. This suggests that QPS as measured with PIVOT technology does correlate with healthy in vivo knee kinematics, but QPS does not correlate with in vivo kinematics following ACLR with or without LET.

Anterior Tibial Subluxation of Lateral Compartment Is Associated With High-Grade Rotatory Instability for Acute But Not Chronic Anterior Cruciate Ligament Injuries: An Magnetic Resonance Imaging Case-Control Study

PURPOSE

To investigate whether anterior tibial subluxation obtained from magnetic resonance imaging (MRI) could be a predictor of high-grade rotatory instability for anterior cruciate ligament (ACL) injuries, including acute and chronic cases.

METHODS

From September 2016 to August 2018, we retrospectively investigated 163 patients with ACL injuries who subsequently underwent primary ACL reconstruction. Among them, 30 patients with high-grade rotatory instability (grade II/III pivot shift) were included in the high-grade group, and their age and sex were matched 1:2 to low-grade cases (<grade II pivot shift). On preoperative MRI, we measured anterior tibial subluxation, posterior tibial slope, as well as the time from injury to surgery. Meniscal lesions were documented from arthroscopy. Multivariable logistic regression was used to determine predictors of high-grade rotatory instability. Furthermore, subgroup comparisons between 2 groups were divided into acute (≤3 months) and chronic (>3 months) phases.

RESULTS

The high-grade group had a larger anterior tibial subluxation of lateral compartment (8.1 mm vs 5.9 mm; P =.004) than the low-grade group, whereas no significant difference was found in anterior tibial subluxation of medial compartment (P > .05). Moreover, high-grade anterior tibial subluxation of lateral compartment (≥6 mm) was found to be an independent predictor (odds ratio, 12.992; P = .011) associated with concomitant meniscal tears after ACL injuries. Anterior tibial subluxation of lateral compartment demonstrated statistical significance between the two groups when comparing subgroups within 3 months but not beyond 3 months.

CONCLUSION

In ACL-injured patients, high-grade anterior tibial subluxation of lateral compartment (≥6 mm) could be a unique predictor of high-grade knee rotatory instability for acute but not chronic injuries. Prolonged time from injury to surgery and lateral meniscus tears were risk factors for high-grade rotatory laxity in chronic patients.

LEVEL OF EVIDENCE

Level III, retrospective prognostic trial.

Superior rotational stability and lower re-ruptures rate after combined anterolateral and anterior cruciate ligament reconstruction compared to isolated anterior cruciate ligament reconstruction: a 2-year prospective randomized clinical trial

PURPOSE

The purpose of the current prospective randomized clinical trial (RCT) was to compare the clinical outcomes of combined anterior cruciate ligament (ACL) and anterolateral ligament (ALL) reconstruction with those of isolated ACL reconstruction and evaluate the re-rupture rate between the two study groups.

METHODS

This prospective RCT included 58 patients (43 men and 15 women) who underwent ACL reconstruction, either isolated (Group I: 26 patients) or combined with the ALL reconstruction (Group II: 32 patients). Preoperatively, the two groups differed in age and rate of medial meniscal injuries. The patients were evaluated preoperatively and postoperatively during the time points corresponding to 6 (T₁) weeks, 12 (T₂) weeks, 6 (T₃) months, 12 (T₄) months, and 24 (T₅) months. The evaluation included the clinical examination (comprising Lachman test, Pivot Shift test, Range of Motion, and Rolimeter differential anterior laxity), the objective clinical score (Objective IKDC [The International Knee Documentation Committee] score), and the subjective clinical scores (comprising Subjective IKDC score, Lysholm score, and Tegner activity score). The postoperative complications of all the patients were recorded.

RESULTS

Both the groups reported a significant improvement in clinical scores during the final follow-up as compared to the preoperative value (p < 0.05). The only differences between the two groups were observed with respect to the pivot shift test during each follow-up, wherein more patients from group I reported a pivot shift test grade I as compared to group II (p < 0.05). Three patients from group I reported a re-rupture of the operated knee, whereas no patients from group II reported new ruptures (p = 0.041).

CONCLUSIONS

Combined ACL and ALL reconstruction has proven to be more effective in obtaining a high grade of rotational knee stability during mid-term follow-up as compared to isolated ACL reconstruction along with a significantly lower rate of re-ruptures.

LEVEL OF EVIDENCE

Level I: Randomized Clinical Trial.

REGISTRATION

researchregistry5873: www.researchregistry.com.

The presence of high-grade pivot shift test preoperatively is associated with inferior functional outcomes

BACKGROUND

The effect of high-grade preoperative pivot shift test on outcomes of anterior cruciate ligament (ACL) reconstruction surgery is not very well established. The present study was conducted to study the factors associated with high-grade pivot shift test and effect of high-grade preoperative pivot shift test on functional outcomes after ACL reconstruction surgery.

METHODS

Three hundred and sixty-two patients who underwent primary ACL reconstruction surgery were enrolled in the study. The pivot shift test was performed preoperatively under anesthesia in all patients. Side of the meniscal tear, if present at the time of ACL reconstruction, was documented. Patients were divided into two groups depending upon the grade of pivot shift test: group H, high-grade pivot shift (n = 84/362; 23%); and group L, low-grade pivot shift (n = 278/362; 77%). Patients were further divided into two groups depending upon the duration of injury: acute (<6 months) and chronic (>6 months). The functional assessment was done using Lysholm score and Tegner activity scale.

RESULTS

The presence of lateral meniscus tear (27/84 vs. 53/278) or both menisci tear (29/84 vs. 60/278) was associated with high-grade pivot shift (p < 0.05). Chronic ACL tears were also observed to be associated with high-grade pivot shift (p = 0.03). The mean Lysholm score in group H and group L patients was 93.8 ± 5.1 and 95.2 ± 5.3, respectively (p = 0.04). The mean post-op Tegner activity scale in group H was 6.8 and in group L was 7.3 (p = 0.0001). Also, 181/253 (71.5%) patients returned to same or higher level of sports activity in group L as compared to 33/72 (46%) patients in group H. The incidence of graft failure in groups H and L was 6.5% (5/77) and 1.6% (4/257; p = 0.03), respectively.

CONCLUSIONS

The high-grade pivot shift is associated with chronic ACL tear (>6 months) and concomitant lateral meniscus tear. The presence of high-grade pivot shift preoperatively is associated with inferior clinical outcomes and lower rate of return to sports.

LEVEL OF EVIDENCE

Level IV, case-control study.

Grade III pivot shift as an early sign of knee decompensation in chronic ACL-injured knees with bimeniscal tears

PURPOSE

To analyse possible associations between the preoperative pivot shift (PS) test and both patient and injury characteristics in anterior cruciate ligament (ACL)-injured knees, considering previously neglected meniscal injuries such as ramp and root tears. The hypothesis was that a preoperative grade III PS was associated with the amount of intra-articular soft-tissue damage and chronicity of the injury.

METHODS

The cohort involved 376 patients who underwent primary ACL reconstruction (239 males/137 females; median age 26). Patients were examined under anesthesia before surgery, using the PS test. During arthroscopy, intra-articular soft-tissue damage of the injured knee was classified as: (1) partial ACL tear; (2) complete isolated ACL tear; (3) complete ACL tear with one meniscus tear; and (4) complete ACL and bimeniscal tears. Chi-square and Mann-Whitney U tests were used to evaluate whether sex, age, body mass index, sport at injury, mechanism of injury, time from injury and intra-articular damage (structural damage of ACL and menisci) were associated with a grade III PS. Intra-articular damage was further analyzed for two sub-cohorts: acute (time from injury ≤ 6 months) and chronic injuries (> 6 months).

RESULTS

A grade III PS test was observed in 26% of patients. A significant association with PS grading was shown for age, time from injury and intra-articular soft-tissue damage (p < 0.05). Further analyses showed that grade III PS was associated with intra-articular damage in chronic injuries only (p < 0.01). In complete ACL and bimeniscal tears, grade III PS was more frequent in chronic (53%) than in acute knee injuries (26%; p < 0.01). Patients with chronic complete ACL and bimeniscal tears had a grade III PS 3.3 [1.3-8.2] times more often than patients in the acute sub-cohort.

CONCLUSION

In ACL-injured patients, a preoperative grade III PS was mainly associated with a higher amount of intra-articular soft-tissue damage and chronicity of the injury. Patients with complete chronic ACL injuries and bimeniscal tears were more likely to have a preoperative grade III PS than their acute counterparts. This suggests that grade III PS may be an early sign of knee decompensation of dynamic rotational knee laxity in chronic ACL-injured knees with bimeniscal lesions.

LEVEL OF EVIDENCE

Level III.

Current trends in the anterior cruciate ligament part II: evaluation, surgical technique, prevention, and rehabilitation

Clinical evaluation and management of anterior cruciate ligament (ACL) injury is one of the most widely researched topics in orthopedic sports medicine, giving providers ample data on which to base their practices. The ACL is also the most commonly treated knee ligament. This study reports on current topics and research in clinical management of ACL injury, starting with evaluation, operative versus nonoperative management, and considerations in unique populations. Discussion of graft selection and associated procedures follows. Areas of uncertainty, rehabilitation, and prevention are the final topics before a reflection on the current state of ACL research and clinical management of ACL injury. Level of evidence V.

Intraoperative pivot-shift accelerometry combined with anesthesia improves the measure of rotatory knee instability in anterior cruciate ligament injury

Purpose

The knee stiffness acquired following an Anterior Cruciate Ligament (ACL) injury might affect clinical knee tests, i.e., the pivot-shift maneuver. In contrast, the motor effects of spinal anesthesia could favor the identification of rotatory knee deficiencies prior to ACL reconstruction. Hence, we hypothesized that the intra-operative pivot-shift maneuver under spinal anesthesia generates more acceleration in the lateral tibial plateau of patients with an injured ACL than without.

Methods

Seventy patients with unilateral and acute ACL rupture (62 men and 8 women, IKDC of 55.1 ± 13.8 pts) were assessed using the pivot-shift maneuver before and after receiving spinal anesthesia. A triaxial accelerometer was attached to the skin between Gerdys’ tubercle and the anterior tuberosity to measure the subluxation and reduction phases. Mixed ANOVA and multiple comparisons were performed considering the anesthesia and leg as factors (alpha = 5%).

Results

We found a higher acceleration in the injured leg measured under anesthesia compared to without anesthesia (5.12 ± 1.56 m.s^− 2 vs. 2.73 ± 1.19 m.s^− 2, p < 0.001), and compared to the non-injured leg (5.12 ± 1.56 m.s^− 2 vs. 3.45 ± 1.35 m.s^− 2, p < 0.001). There was a presence of significant interaction between leg and anesthesia conditions (p < 0.001).

Conclusions

The pivot-shift maneuver performed under anesthesia identifies better rotatory instability than without anesthesia because testing the pivot-shift without anesthesia underestimates the rotatory subluxation of the knee by an increased knee stiffness. Thus, testing under anesthesia provides a unique opportunity to determine the rotational instability prior to ACL reconstruction.

Effects of Anterolateral Structure Augmentation on the In Vivo Kinematics of Anterior Cruciate Ligament-Reconstructed Knees

BACKGROUND

Double-bundle anterior cruciate ligament (ACL) reconstruction (ACLR) is a well-known treatment that restores the stability of ACL-deficient knees. However, some isolated ACL-reconstructed knees ultimately show rotatory laxity and develop osteoarthritis. Whether combined ACLR with anterolateral structure (ALS) augmentation (ALSA) can provide better improvement in the in vivo knee rotational kinematics remains unknown.

HYPOTHESIS

When compared with isolated double-bundle ACLR, combined double-bundle ACLR with ALSA can improve knee in vivo rotational kinematics and provide better restoration of knee kinematics.

STUDY DESIGN

Controlled laboratory study.

METHODS

Sixteen patients with unilateral ACL injury were randomly divided into 2 groups to receive either combined double-bundle ACLR and ALSA (ALSA group) or isolated double-bundle ACLR (ACLR group). All patients performed a single-leg lunge using the operative and nonoperative/contralateral legs under dual-fluoroscopic imaging system surveillance during a hospital visit at a minimum 1 year (12-13 months) of follow-up to assess the 6 degrees of freedom knee kinematics. Functional evaluation using the Lysholm and Marx rating scales and clinical examinations were also performed.

RESULTS

From full extension to approximately 90° of knee flexion at 5° intervals, the mean ± SD internal rotation of the reconstructed knees in the ALSA group (1.5°± 0.9°) was significantly smaller than that of the contralateral knees (8.2°± 1.9°; P = .008). The ALSA group knees also showed significantly (P = .045) more medial translation than the contralateral knees. In the ACLR group, the mean internal rotation of the reconstructed knee (6.0°± 2.1°) was significantly smaller than that of the contralateral knees (8.9°± 0.6°; P < .001). At full extension, the tibia was significantly more externally rotated than that of the contralateral legs (0.5°± 7.4° vs 7.6°± 3.4°, P = .049).

CONCLUSION

When compared with isolated double-bundle ACLR, double-bundle ACLR augmented with ALS reconstruction resulted in anterolateral rotatory overconstraint during the lunge motion.

CLINICAL RELEVANCE

Additional ALSA of double-bundle ACL-reconstructed knees overconstrained rotatory stability. Therefore, the use of ALSA for ACL-reconstructed knees should be considered with caution for patients with ACL deficiency and anterolateral rotatory instability. Longer-term follow-up to evaluate long-term outcomes and altered kinematics over time is recommended.