Excessive tibial rotation during high-demand activities is not restored by anterior cruciate ligament reconstruction

Anterior Cruciate Ligament Reconstruction Using Lateral Extra-Articular Procedures: A Systematic Review

Background and Objectives: The present systematic review investigated the efficacy of lateral extra-articular tenodesis (LET) and anterolateral ligament (ALL) as lateral extra-articular procedures (LEAPs) for anterior cruciate ligament (ACL) reconstruction. ACL reconstruction using LEAP may reduce graft rupture and rotatory laxity and allow a quicker return to sports. The outcomes of interest were patient-reported outcome measures (PROMs), return to sport, laxity, failure rate, and safety profile. Materials and Methods: The present systematic review followed the 2020 PRISMA guidelines. In December 2024, PubMed, EMBASE, and Web of Science were accessed without constraints. All clinical investigations evaluating LEAP for ACL reconstruction were considered. Only studies that considered LET and ALL as LEAP were considered. Only studies using a hamstring tendon autograft associated with LET or ALL were considered. Results: Data from 27 clinical studies (3423 patients) were retrieved. The mean length of follow-up was 61.8 ± 39.5 months. ACL reconstruction using LEAP led to a statistically significant improvement in the Lysholm score (p < 0.01) and IKDC (p < 0.01). The mean joint laxity, as measured by the arthrometer, was 1.5 ± 1.8 mm. Finally, 72.3% (623 of 668) of patients returned to their pre-injury level of sport at a mean of 6.3 ± 4.4 months. At the last follow-up, the LET group showed greater IKDC (p = 0.04). On the other hand, there was a statistically significant greater rate of patients positive to the Lachman test (p < 0.01), return to sport (p < 0.01), and reoperation (p = 0.01). No significant differences were found in Lysholm scores (p = 0.6), Tegner scores (p = 0.2), arthrometer measurements (p = 0.2), Pivot shift test results (p = 0.1), time to return to sport (p = 0.3), and failure rates (p = 0.7). Conclusions: LEAP for ACL reconstructions seems to be effective and safe. Most patients returned to their pre-injury level of sport after a mean of 6 months. LET-based ACL reconstruction may be associated with greater clinical outcomes and a higher reoperation rate compared to ALL-based reconstruction.

The Role of Isolated Lateral Extra-Articular Tenodesis in Managing Residual Pivot Shift After Primary Anterior Cruciate Ligament Reconstruction and a New Medial Meniscal Tear

Background

Persistent mildly abnormal knee kinematics after anterior cruciate ligament (ACL) reconstruction (ACLR) is an ongoing clinical problem.

Purpose

To compare the clinical outcomes of revision ACLR (rACLR), rACLR and lateral extra-articular tenodesis (LET), or isolated LET in patients with a grade ≥2 pivot shift after ACLR with an intact or partially torn graft and a new, symptomatic medial meniscal tear.

Study Design

Cohort study; Level of evidence, 3.

Methods

A retrospective review of all patients with a new, symptomatic medial meniscal tear diagnosed after a primary ACLR was performed. Patients were included if they demonstrated a grade ≥2 pivot shift on physical examination with an intact or partially torn ACL graft. Exclusion criteria included complete graft rupture. The senior author's management evolved in a practice change design from rACLR to rACLR with LET, to isolated LET over the study period. The primary outcomes were the International Knee Documentation Committee (IKDC), Lysholm, and Tegner patient-reported outcomes (PROs) at 2 years postoperatively.

Results

A total of 47 patients, with 16 in the rACLR group, 12 in the rACLR and LET group, and 19 in the isolated LET group were included. Baseline characteristics between groups were similar. At 2 years, the rACLR group IKDC score was 86.1 ± 6.6 and was lower than the rACLR and LET group (91.9 ± 4.4; P = .009; 95% CI, -10.4 to -1.2) and the isolated LET group scores (91.7 ± 3.0; P = .004; 95% CI, -9.7 to -1.6). The Lysholm score was lower in the rACLR group (85.8 ± 6.3) when compared with the rACLR and LET group (91.8 ± 4.6; P = .03; 95% CI, -11.8 to -0.39). There was no difference in any Tegner scores at 2 years (P = .09).

Conclusion

In patients with grade ≥2 pivot shift after an ACLR with an intact or partially torn graft and a new, symptomatic medial meniscal tear, the addition of an LET with or without rACLR led to improved PROs compared with an isolated rACLR. An isolated LET in this patient population should be considered an acceptable treatment option.

Sensor-based technologies for motion analysis in sports injuries: a scoping review

BACKGROUND

Insightful motion analysis provides valuable information for athlete health, a crucial aspect of sports medicine. This systematic review presents an analytical overview of the use of various sensors in motion analysis for sports injury assessment.

METHODS

A comprehensive search of PubMed/MEDLINE, Scopus, and Web of Science was conducted in February 2024 using search terms related to "sport", "athlete", "sensor-based technology", "motion analysis", and "injury." Studies were included based on PCC (Participants, Concept, Context) criteria. Key data, including sensor types, motion data processing methods, injury and sport types, and application areas, were extracted and analyzed.

RESULTS

Forty-two studies met the inclusion criteria. Inertial measurement unit (IMU) sensors were the most commonly used for motion data collection. Sensor fusion techniques have gained traction, particularly for rehabilitation assessment. Knee injuries and joint sprains were the most frequently studied injuries, with statistical methods being the predominant approach to data analysis.

CONCLUSIONS

This review comprehensively explains sensor-based techniques in sports injury motion analysis. Significant research gaps, including the integration of advanced processing techniques, real-world applicability, and the inclusion of underrepresented domains such as adaptive sports, highlight opportunities for innovation. Bridging these gaps can drive the development of more effective, accessible, and personalized solutions in sports health.

Comparison of bilateral ligaments after unilateral anterior cruciate ligament reconstruction: Based on magnetic resonance imaging analysis

OBJECTIVE

This study quantitatively assessed postoperative changes in graft inclination angle and femorotibial position after ACL reconstruction using MRI, to identify reliable indicators for evaluating knee stability.

METHODS

A retrospective analysis of 50 cases of ACL reconstruction from June 2019 to June 2020 included clinical outcome measures. MRI assessed graft/ACL inclination angles, medial/lateral anterior tibial translation (ATT), and femoral/tibial rotation angles on both surgical and contralateral sides. Femorotibial angle (FTA) and rotational tibial subluxation (RTS) were calculated for comparing MRI results.

RESULTS

Following ACL reconstruction, graft inclination angles, ATT, and FA/TA were significantly greater than those of the contralateral knee joint (P<0.05). FTA and RTS did not differ significantly between sides, but exhibited significant correlation.

CONCLUSIONS

Graft inclination angles could not fully recover to normal levels post-ACL reconstruction, while notable medial/lateral ATT occurred on the surgical side. Additionally, a significant correlation was observed between FTA and RTS, suggesting their potential as combined clinical indicators for assessing knee joint rotation stability.

Combined Anterior Cruciate Ligament and Anterolateral Ligament Reconstruction Using the Superficial Layer Quadriceps Tendon Graft: Surgical Technique Description

We present a technique for the combined anterior cruciate ligament (ACL) and anterolateral ligament (ALL) reconstruction using the superficial layer quadriceps tendon graft. Anatomic reconstruction is achieved with outside-in femoral tunnel drilling. The femoral drill guide has an intra-articular placement at the femoral footprint of the ACL and an extra-articular placement at the femoral ALL attachment. This surgical technique does not need any special instruments and consists of 3 bone tunnels. The long length and customized superficial quadriceps tendon graft is harvested in a minimally invasive manner and allows an accessible and low-cost reconstruction of both ligaments.

Modified Lemaire Lateral Extra-Articular Tenodesis Using an Inlay Technique and All-Suture Knotless Anchor Fixation

Appreciation of persistent anterolateral rotatory instability and graft failure after anterior cruciate ligament (ACL) reconstruction procedures has led surgeons to adopt the addition of lateral extra-articular tenodesis (LET) in both the revision and primary setting. Multiple techniques have been shown to eliminate anterolateral rotatory instability and reduce forces on the ACL graft, which has translated to lower re-rupture rates and improved patient outcomes. The risk of ACL/LET tunnel convergence can potentially compromise the fixation of one or both graft reconstructions. This article describes a technique for LET fixation which minimizes the depth of the LET femoral bone socket and utilizes low-profile implants thus mitigating this risk.

Comparison of ACL and Anterolateral Ligament Reconstruction With Isolated ACL Reconstruction Using Hamstring Autograft: Outcomes in Young Female Patients With High-Grade Pivot Shift

Background

Inferior return to sports (RTS) and functional outcomes have been reported in women after anterior cruciate ligament reconstruction (ACLR).

Purpose/Hypothesis

The purpose was to evaluate the results of combined ACLR and anterolateral ligament reconstruction (ALLR) in young women with a high-grade pivot shift (grade ≥2). It was hypothesized that combined ACLR and ALLR would result in better RTS and rotational stability than isolated ACLR.

Study Design

Cohort study; Level of evidence, 3.

Methods

Two groups were retrospectively evaluated and compared. Group I (n = 39; mean age, 31.1 ± 5.7 years) underwent isolated ACLR using hamstring autografts; group C (n = 39; mean age, 30.4 ± 6.1 years) underwent combined ACLR and ALLR. Subjective outcome measures included the International Knee Documentation Committee subjective form, Lysholm, Tegner, and ACL-Return to Sport after Injury (ACL-RSI). Objective tests included a KT-2000 arthrometer stress test, a pivot-shift test, an isokinetic strength test, a Y-balance test, and a single-leg hop test. A postoperative questionnaire was administered to determine the rates and types of RTS, quality of sports performance, and reinjury and satisfaction rates. Subjective scores and clinical tests were performed at 2 years. Magnetic resonance imaging and second-look arthroscopy were conducted during the 1- and 2-year follow-ups, respectively.

Results

The mean follow-up for groups I and C were 30.4 ± 3.9 and 29.3 ± 3.5 months, respectively (P = .194). Patients in group C had better anteroposterior (P = .001) and rotational (P = .005) stability and higher ACL-RSI scores (P = .025) than those in group I. Group C had higher composite and posteromedial reach scores on the Y-balance test than group I (P = .014 and P = .010, respectively). A total of 26 (66.7%) patients in group C and 17 (43.6%) in group I returned to their prior level of sports (P = .040). Rerupture of the ACL graft and contralateral ACL rupture occurred in 2 (5.1%) and 2 (5.1%) patients in group I, respectively, compared with no rerupture or contralateral ACL rupture in group C.

Conclusion

Combined ACLR and ALLR in young women with a high-grade pivot shift was associated with better knee stability parameters, dynamic postural stability, and psychological readiness to RTS than isolated ACLR.

Review of Cha et al. (2005) on "Arthroscopic Double Bundle Anterior Cruciate Ligament Reconstruction: An Anatomical Approach"

This classic discusses the original publication 'Arthroscopic double-bundle anterior cruciate ligament reconstruction (ACL): An anatomical approach', the first detailed description of the surgical technique popularised by Dr Freddie Fu. The technique, in which the anteromedial and posterolateral bundles of the ACL are reconstructed individually using two grafts with independent bone tunnels, was designed to more closely recreate the function of the native ACL by more closely reproducing the functional anatomy. This reconstruction was biomechanically superior to single-bundle reconstruction, particularly with regards to rotational control, leading to great interest from ACL surgeons around the world. Clinical superiority was more difficult to demonstrate; however, and the technical difficulty of the procedure has limited its use. Nevertheless, the pursuit of improved patient outcomes through attention to functional anatomical detail continues. 'Recreating the functional anatomy of the intact ACL remains the cornerstone of ACL reconstruction'.

Combined Lateral Extra-Articular Tenodesis or Combined Anterolateral Ligament Reconstruction and Anterior Cruciate Ligament Reconstruction Improves Outcomes Compared to Isolated Reconstruction for Anterior Cruciate Ligament Tear: A Network Meta-analysis of Randomized Controlled Trials

PURPOSE

To conduct a network meta-analysis (NMA) comparing the results of randomized controlled trials (RCTs) among patients who underwent either isolated anterior cruciate ligament (ACL) reconstruction or combined lateral extra-articular tenodesis (LET) or anterolateral ligament reconstruction (ALLR).

METHODS

RCTs that compared isolated ACL reconstruction and combined LET or ALLR were included with minimum 12 months follow-up. Studies that used the double-bundle technique were excluded. Outcome assessment included the number of positive pivot shifts, amount of anterior tibial translation, and International Knee Documentation Committee (IKDC) subjective, Tegner, and Lysholm scores. Bayesian NMA and the surface under the cumulative ranking area (SUCRA) were evaluated.

RESULTS

A total of 1,077 patients from 11 RCTs were enrolled in this study. In NMA, the odds ratios (ORs) of positive pivot shift were significantly lower in ACL + ALLR (OR: 0.17; 95% CI: 0.027-0.67) than isolated ACL reconstruction, but no difference between ACL + ALLR and ACL + LET. There were no significant differences in anterior tibial translation among the techniques, but the IKDC subjective and Lysholm scores of ACL + ALLR and ACL + LET were significantly higher than isolated ACL reconstruction. ACL + ALLR were the most preferred in terms of residual pivot shift, anterior tibial translation, and IKDC subjective scores (SUCRA = 88.2%, 86.4%, and 93.1%, respectively). Additional lateral procedures resulted in significantly lower risk of graft failure (OR: 0.27; 95% CI: 0.1-0.71) than isolated ACL reconstruction.

CONCLUSIONS

ACL + ALLR were found to have significantly better outcomes in terms of knee rotational stability and graft failure rate than isolated ACL reconstructions, but the clinical outcomes were uncertain after a minimum 12 months follow-up. Considering the greatest probability of obtaining better knee rotational stability in this NMA, ACL + ALLR was found to be the most preferred technique for patients with ACL injury.

LEVEL OF EVIDENCE

Level II, network meta-analysis and systematic review of Level I and II studies.

Anatomy, Biomechanics, and Reconstruction of the Anterolateral Ligament of the Knee Joint

Despite remarkable advances in the clinical outcomes after anterior cruciate ligament reconstructions (ACLRs), residual rotational instability of the knee joint remains a major concern. Since the anterolateral ligament (ALL) on the knee joint has been “rediscovered”, the role of anterolateral structures, including ALL and deep iliotibial band, as secondary stabilizers of anterolateral rotatory instability has gained interest. This interest has led to the resurgence of anterolateral procedures combined with ACLRs to restore rotational stability in patients with anterior cruciate ligament (ACL) deficiencies. However, the difference in concepts between anterolateral ligament reconstructions (ALLRs) as anatomical reconstruction and lateral extra-articular tenodesis (LETs) as non-anatomical reinforcement has been conflicting in present literature. This study aimed to review the anatomy and biomechanics of anterolateral structures, surgical techniques, and the clinical outcomes of anterolateral procedures, including LET and ALLR, in patients with ACL deficiencies.

Magnetic resonance imaging does not reliably detect Kaplan fiber injury in the setting of anterior cruciate ligament tear

PURPOSE

There has been a continued effort to better understand the role Kaplan fiber injury plays in persistent instability following ACL tears. However, the prevalence of these injuries remains poorly understood. Therefore, the purpose of this study was to define the prevalence of Kaplan fiber injury in the setting of complete anterior cruciate ligament tear using a commonly used grading system for assessing ligament injuries. The inter-rater reliability of this commonly used grading system and the relationship between Kaplan fiber injury and injury to other structures commonly found in conjunction with ACL tears was also evaluated.

METHODS

All isolated, complete anterior cruciate ligament tears confirmed on magnetic resonance imaging within 90 days of injury between 2014 and 2020 at a single institution were included for analysis. Each scan was read by two, fellowship-trained musculoskeletal radiologists. Kaplan fiber injury was evaluated using a previously described grading scheme. Kappa, [Formula: see text], of inter-rater agreement was determined for all magnetic resonance image scans. Kruskal Wallis test was performed to assess for associations between Kaplan fiber injury and magnet strength (1.5 T vs. 3.0 T), patient gender, the presence of medial and/or lateral meniscal tears, and/or posterolateral tibial bone bruise.

RESULTS

Between 2014 and 2020, 131 patients (94 males, 37 females) with a complete anterior cruciate ligament tear were included in the final analysis. The mean age of the cohort was 27.8 ± 6.8 years. Kaplan fiber injuries were identified in 51 of 131 (38.9%, CI 31.0-47.5%) scans with complete anterior cruciate ligament injuries (Grade 1: 28, Grade 2: 18, and Grade 3: 5). Inter-rater agreement for Kaplan fiber injury was fair ([Formula: see text] with 43 (32.8%) scans requiring third reviewer adjudication. There were no significant associations between Kaplan fiber injury and gender, magnet strength, meniscal tears, or posterolateral tibial bone bruise.

CONCLUSION

The prevalence of Kaplan fiber injuries was comparable to previously described rates; however, the classification system used to report Kaplan fiber injury was associated with low inter-rater reliability. The presence of Kaplan fiber injury was not associated with other injuries commonly observed in conjunction with ACL tear. The previously proposed Kaplan fiber injury classification system is not reproducible nor is it likely to aid surgeons in distinguishing higher grades of rotatory knee instability.

LEVEL OF EVIDENCE

Level IV.

Anterior Cruciate Ligament Reconstruction Alone Versus With Lateral Extra-articular Tenodesis With Minimum 2-Year Follow-up: A Meta-analysis and Systematic Review of Randomized Controlled Trials

BACKGROUND

Lateral extra-articular tenodesis (LEAT) aims to improve anterolateral stability of the injured knee during anterior cruciate ligament reconstruction (ACLR) surgery. Inconclusive evidence surrounding the efficacy and safety of LEAT has propelled clinical interest and ongoing discussions.

PURPOSE

To establish level 1 evidence by assessing randomized controlled trials (RCTs) with minimum 2-year follow-up that directly compared ACLR with LEAT (LEAT group) and ACLR alone (non-LEAT group) in terms of clinical outcomes and complications.

STUDY DESIGN

Meta-analysis and systematic review; Level of evidence, 1.

METHODS

Meta-analysis was performed with a multidatabase search (Cochrane, EMBASE, OVID Medline, PubMed, and Web of Science) according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines on September 9, 2020. Data from published RCTs meeting inclusion criteria were extracted and analyzed with an inverse variance statistical model.

RESULTS

A total of 7 RCTs were included, consisting of 517 LEAT and 589 non-LEAT patients. Only autografts were used for ACLR and LEAT. A variety of LEAT techniques and autograft fixation methods were used. We found improved stability (residual positive pivot shift: risk ratio [RR], 0.59; 95% CI, 0.39-0.88; P = .01) and better clinical outcomes (International Knee Documentation Committee [IKDC] score: mean difference [MD], 2.31; 95% CI, 0.54-4.09; P = .01; and Lysholm score: MD, 2.71; 95% CI, 0.68-4.75; P = .009) in the LEAT than non-LEAT group. Graft rerupture rate was 3 times less likely (RR, 0.31; 95% CI, 0.17-0.58; P < .001) in the LEAT group than the non-LEAT group.

CONCLUSION

Good-quality evidence is available to support the efficacy of LEAT in improving anterolateral knee stability and reducing graft reruptures in primary ACLR. LEAT should be considered in patients with high risk factors. Although Lysholm and IKDC scores were statistically better in the LEAT group, these are unlikely to be clinically significant. Future studies should aim to identify patient populations that would best benefit from LEAT with ACLR.

ACL Reconstruction Combined With the Arnold-Coker Modification of the MacIntosh Lateral Extra-articular Tenodesis: Long-term Clinical and Radiological Outcomes

BACKGROUND

Interest in the role of lateral extra-articular tenodesis (LET) in preventing rotatory instability and the pivot-shift phenomenon after anterior cruciate ligament reconstruction (ACLR) has been recently renewed. Nevertheless, there is still concern about overconstraint of the lateral compartment of the knee and the risk of subsequent osteoarthritis (OA).

PURPOSE

The purpose of this retrospective study was to compare long-term subjective and objective outcomes and the rate of OA development between patients undergoing isolated ACLR (iACLR) with a hamstring tendon autograft and those with a combined Arnold-Coker modification of the McIntosh extra-articular procedure. Risk factors for long-term OA were evaluated.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

The study included 165 consecutive patients treated at a single center by ACLR. A total of 86 patients underwent iACLR (iACLR group) and 79 received combined intra- and extra-articular reconstruction (ACLR+LET). The International Knee Documentation Committee (IKDC), Lysholm, and Tegner activity scores were administered. Knee stability was tested through the Lachman test, the pivot-shift test, and the KT-1000 knee arthrometer test. A positive pivot-shift test (++/+++), laxity on the KT-1000, and referred giving-way episodes or revision ACLR were considered failures. Radiographic results were assessed according to the Fairbank, IKDC, and Kellgren-Lawrence scales. Radiographic evaluation included both the overall tibiofemoral joint and the medial and lateral compartment separately. A univariate and a multivariate logistic regression with penalized maximum likelihood was used to identify risks factors associated with long-term OA.

RESULTS

The mean follow-up was 15.7 years. There were no statistically significant differences in subjective scores between the 2 groups. A side-to-side difference >5 mm on the KT-1000 arthrometer evaluation was found in 8 patients in the iACLR group and in 1 patient in the ACLR+LET group (P = .01). Nine cases of failure were found in the iACLR group and only 1 case was found in the ACLR+LET group (P = .0093). Patients in the iACLR group had a significantly higher OA grades than those in the ACLR+LET group for the overall tibiofemoral joint and the lateral compartment of the knee. No differences were found in the medial compartment. A higher level of lateral compartment OA was found in patients who received partial lateral meniscectomy in the iACLR group compared with those in the ACLR+LET group. Univariate and multivariate analysis results demonstrated that meniscectomy was the most significant factor for long-term OA development.

CONCLUSION

A significantly higher risk of long-term OA was found with iACLR than with ACLR combined with the Arnold-Coker modification of the McIntosh extra-articular procedure. Knees with combined ACLR also had a significantly lower OA grade after partial lateral meniscectomy. Additionally, those undergoing combined ACLR had better knee stability and lower graft rupture rates at the long-term follow-up. Partial meniscectomy was the main risk factor negatively associated with OA changes.

Medial meniscus ramp and lateral meniscus posterior root lesions are present in more than a third of primary and revision ACL reconstructions

PURPOSE

The purpose of this study was (1) to describe the meniscus tear pattern in anterior cruciate ligament (ACL)-injured patients, with a special focus on medial meniscus (MM) ramp lesions and lateral meniscus (LM) root tears and (2) to determine whether patient and injury characteristics were associated with meniscus tear patterns.

METHODS

Data from 358 cases of ACL primary and revision reconstruction surgeries were extracted from a center-based registry. During arthroscopy, the presence of associated meniscus lesions was documented by systematically inspecting the anterior and posterior tibiofemoral compartments. With a special focus on MM ramp lesions and LM root tears, groups of different injury tear patterns were formed. Chi-square tests were used to determine whether these groups differed with respect to various patient and injury characteristics, including gender, previous ipsilateral ACL injuries, the injury's relation to sport, person contact during injury and the type of ACL tear. Median age at surgery and body mass index were compared between groups using the Kruskal-Wallis test. Significance was set at p < 0.05.

RESULTS

Two hundred and thirty-nine ACL injuries (67%) showed additional meniscal injuries, of which 125 (52%) involved the MM ramp and/or the LM root. Ramp lesions were more frequent in males (23% vs 12% in females, p < 0.01), in contact injuries (28% vs 16% in non-contact, p < 0.05) and in complete ACL tears (21% vs 5% in partial, p < 0.05). Combined injuries of the MM ramp and the LM root showed a higher percentage of contact injuries compared to non-contact injuries (10% vs 4%, p < 0.05).

CONCLUSION

Two-thirds of all ACL injuries showed a concomitant meniscus injury, of which half involved the biomechanically relevant, but previously often undiagnosed RLMM or the PRLM. These findings provide evidence that until recently about half of ACL-associated meniscus injuries were not properly identified. Ramp lesions were more frequent in males, contact injuries and in complete ACL tears. These findings stress the need for a systematic assessment and a better understanding of the pathomechanism of these specific injuries which may have an important impact on knee biomechanics and the outcome of ACL reconstruction.

LEVEL OF EVIDENCE

III.

Cortical Motor Planning and Biomechanical Stability During Unplanned Jump-Landings in Males With ACL-Reconstruction

CONTEXT

Athletes with anterior cruciate ligament (ACL) reconstruction exhibit increased cortical motor planning during simple sensorimotor tasks compared to healthy controls. This may interfere with proper decision-making during time-constrained movements elevating the re-injury risk.

OBJECTIVE

To compare cortical motor planning and biomechanical stability during jump-landings between participants with ACL-reconstruction and healthy individuals.

DESIGN

Cross-sectional exploratory study.

SETTING

Laboratory patients or other participants: Ten males with ACL-reconstruction (28±4 yrs., 63±35 months post-surgery) and 17 healthy males (28±4 yrs.) completed pre-planned (landing leg shown before take-off; n=43±4) and unplanned (visual cue during flight; n=51±5) countermovement-jumps with single-leg-landings.

MAIN OUTCOME MEASURES

Movement-related cortical potentials (MRCP) and frontal theta frequency power before the jump were analyzed using electroencephalography. MRCP were subdivided into three successive 0.5 sec epochs (readiness potential 1 and 2; RP and negative slope; NS) relative to movement onset (higher values indicative of more motor planning). Theta power was calculated for the last 0.5 sec prior to movement onset (higher values indicative of more focused attention). Biomechanical landing stability was measured via vertical peak ground reaction force, time to stabilization, and center of pressure.

RESULTS

Both conditions evoked MRCP at all epochs in both groups. During the unplanned condition, the ACL-reconstructed group exhibited slightly, but not significantly higher MRCP (RP-1:p=0.651, d=0.44, RP-2:p=0.451, d=0.48; NS:p=0.482, d=0.41). The ACL-reconstructed group also showed slightly higher theta power values during the pre-planned (p=0.175, d=0.5) and unplanned condition (p=0.422, d=0.3) reaching small to moderate effect sizes. In none of the biomechanical outcomes, both groups differed significantly (p>0.05). No significant condition and group interactions occurred (p>0.05).

CONCLUSIONS

Our jump-landing task evoked MRCP. Although not significant between groups, the observed effect sizes provide first indication that males with ACL-reconstruction may persistently rely on more cortical motor planning associated with unplanned jump-landings. Confirmatory studies with larger sample sizes are warranted.

TRIAL REGISTRY

clinicalTrials.gov (NCT03336060).

Editorial Commentary: Knee Anterolateral Ligament Cadaveric, Biomechanical Analysis Should Include Tensioning of All Knee Dynamic Structures

Although most reports in the literature suggest that the knee anterolateral structures contribute to the anterolateral rotational stability of the knee, the extent of its contribution is still controversial. There are many dynamic structures that also affect the stability of the knee joint, including the iliotibial band and quadriceps muscle. Although not all of the dynamic structures surrounding the knee influence stability associated with the anterior cruciate ligament, we recommend that cadaveric, biomechanical analysis of the knee anterolateral ligament and related structures include tensioning of all knee dynamic structures to avoid potential biases.

Anterolateral ligament reconstruction improves the clinical and functional outcomes of anterior cruciate ligament reconstruction in athletes

PURPOSE

To compare the outcomes of anterior cruciate ligament (ACL) reconstruction with those of combined ACL and anterolateral ligament (ALL) reconstruction in ACL-deficient knees. The objective of this study was to improve knowledge regarding the treatment of ACL-deficient knees with combined ACL and ALL reconstruction. Combined ACL and ALL reconstruction has been hypothesized to result in better clinical and functional outcomes than isolated ACL reconstruction (ACLR).

METHODS

One-hundred and seven adult male athletes with ACL tears and high-grade pivot shifts were randomized into two groups. Those in group A (n = 54) underwent ACLR, while those in group B (n = 53) underwent combined ACL and ALL reconstruction. The median age was 26 (18-40) and 24 (18-33) years in groups A and B, respectively, and the median follow-up was 60 (55-65) months. Physical examination findings, instrumented knee laxity tested using a KT-1000 arthrometer, and International Knee Documentation Committee Scale (IKDC) scores were used to evaluate the outcomes.

RESULTS

One-hundred and two patients were available for follow-up: 52 in group A and 50 in group B. Postoperatively, the pivot shift was normal in 43 (82.7%) and 48 (96%) patients in groups A and B, respectively (p < 0.001). The median instrumented knee laxity was 2.5 ± 0.7 (1.2-6.1) mm in patients in group A and 1.2 ± 0.7 (1.2-3.2) mm in patients in group B (p < 0.001). Additionally, 44 (84.6%) patients in group A had normal IKDC scores and 3 (5.8%) had nearly normal scores, while 48 (96.0%) patients in group B had normal IKDC scores and 2 (4%) had nearly normal scores (p < 0.001).

CONCLUSION

Combined ACL and ALL reconstruction, compared with isolated ACLR resulted in favourable clinical and functional outcomes, as demonstrated by decreased rotational instability and instrumented knee laxity, a lower graft rupture rate and better postoperative IKDC scores.

LEVEL OF EVIDENCE

1.

Femoral and tibial bone bruise volume is not correlated with ALL injury or rotational instability in patients with ACL-deficient knee

PURPOSE

Some researchers have suggested that bone bruises are evidence of rotational instability. The hypothesis was that the extent of lateral bone edema is correlated with the presence of an anterolateral ligament (ALL) injury. The main objective was to determine whether there was a correlation between the presence of an ALL injury the extent of bone bruises.

METHODS

A prospective diagnostic study enrolled all the patients who suffered an acute anterior cruciate ligament (ACL) who were operated on within 8 weeks. The extent of bone bruising according to the ICRS classification was measured on preoperative MRIs by two independent blinded raters twice with an interval of 4 weeks. Dynamic ultrasonography (US) to look for ALL injury and the pivot shift test were performed before the ACL surgery. The correlation between ALL injury and bone bruises, and the correlation between an ALL injury and a high-grade pivot shift test were determined.

RESULTS

Sixty-one patients were included; 52% of patients had an ALL injury on US. The extent of lateral bone bruise was not related to the presence of an ALL injury, nor related to the presence of a high-grade pivot shift. A grade 2 or 3 pivot shift was significantly correlated with an ALL injury (p < 0.0001). Inter- and intra-rater reliability for the bone bruise rating was excellent.

CONCLUSION

The extent of lateral bone bruise is not correlated with ALL injury or a high-grade pivot shift; thus, it is not correlated with rotational instability of the knee.

LEVEL OF EVIDENCE

II.

Risk of overconstraining femorotibial rotation after anatomical ACL reconstruction using bone patella tendon bone autograft

INTRODUCTION

Numerous studies have focused on the anteroposterior stability after anterior cruciate ligament (ACL) reconstruction, with less emphasis on rotational stability. It has been hypothesized that bone patella tendon bone (BTB) autograft for ACL reconstruction restores knee rotation closely to normal due to its comparable fiber orientation to the native ACL.

MATERIALS AND METHODS

Twenty patients with unilateral ACL rupture and an uninjured contralateral knee were included in this study. The ACL was reconstructed using the medial third of the patellar tendon. Tunnel placement was controlled by fluoroscopy. Implant-free press-fit graft fixation was used on both femoral and tibial side. Bone blocks were carefully placed to restore fiber orientation of both the anteromedial and posterolateral bundle, similar to the native ACL. Rotatory laxity of both knees was measured at 0° and 25° of flexion pre- and post-surgery, using an active opto-electronical motion-analysis system (LUKOTRONIC AS 100^®). All measurements were performed under general anesthesia during surgery.

RESULTS

Knee rotation was reduced significantly in both 0°and 25° of flexion following ACL reconstruction (p < 0.001). The side to side difference (SSD) of the rotatory laxity in extension was greater in the ACL-deficient knee (14.9° ± 8.9°), but decreased significantly after ACL reconstruction (- 5.9° ± 7.7°, minus value means less than in the uninjured knee). There was a similar finding at 25° of knee flexion where greater rotation of the ACL-deficient knee (5.7° ± 10.3°) prior to surgery changed to lower degree of rotation after surgery (- 11.3° ± 8.4°) in comparison to the uninjured knee.

CONCLUSIONS

ACL reconstruction with a BTB graft in anatomical position using press-fit implant-free fixation is able to restore rotatory knee stability close to the intact contralateral knee. Despite the fact that the BTB graft offers fiber orientation close to the natural ACL, the surgeon should be aware of the potential risk of over-constraining the knee in terms of rotation.

LEVEL OF EVIDENCE

II.

ACL reconstruction with lateral extra-articular tenodesis using a continuous graft: 10-year outcomes of 50 cases

BACKGROUND

Persistence of pivot shift is the main problem after isolated intra-articular anterior cruciate ligament (ACL) reconstruction. Adding lateral extra-articular tenodesis (LET) to the ACL procedure increases the knee's stability by controlling rotational laxity. The aim of this study was to evaluate the long-term clinical and radiological outcomes of combined ACL reconstruction with LET using a continuous hamstring graft as a first-line procedure.

MATERIAL AND METHODS

Fifty patients were reviewed at 10 years postoperative. Subjective outcome scores -IKDC, Lysholm, KOOS and Tegner- were collected. A clinical and radiological assessment was done. The knees' anteroposterior laxity was measured with a rollimeter.

RESULTS

The mean IKDC subjective score was 85.5, the mean Lysholm score was 90.2 and 80% of patients had a score graded as good or very good. No pivot shift was present in 94% of patients and there was a firm endpoint in the Lachman test in 86% of patients. There was a flexion deficit>5° in 5 patients and an extension deficit of 10° in one patient. Most patients (56%) had resumed their physical activities at the same level as before the surgery. Signs of osteoarthritis were found in 26% of patients (16% were Ahlback stage 1 and 10% were stage 2). There was only one graft failure. These good outcomes are consistent with other published studies on combined ACL-LET. There was neither significant stiffness, nor a higher rate of secondary osteoarthritis relative to ACL reconstruction only, particularly in the lateral tibiofemoral compartment.

CONCLUSION

Adding primary LET to ACL reconstruction improves control of rotational laxity over time without increasing the complication rate.

LEVEL OF EVIDENCE

IV, retrospective study without control group.

Reconstruction of the anterior cruciate- and anterolateral ligament deficient knee with a modified iliotibial graft reduces instability more than with an intra-articular hamstring graft

PURPOSE

To compare knee kinematics before and after anterior cruciate ligament ACL reconstruction (ACL-R) using hamstring graft (HG) and a double-stranded iliotibial tract graft attached to Gerdy's tubercle (providing an extra-articular anterolateral tenodesis) (named the modified iliotibial tract graft = MIT).

METHOD

Eighteen cadaveric knees were tested in a 6 degree of freedom kinematics rig. An optical tracking system recorded kinematics of the knee from 0 to 80 degrees of flexion applying no load, internal/external rotation (IR/ER), valgus/varus rotation (VGR/VRR), simulated pivot shift (SPS), anterior translation (AT) and posterior translation loads. The knee was tested before and after resection of the ACL and the anterolateral ligament (ALL), respectively; then after HG-ACL-R and MIT-ACL-R. Grafts were fixed at 20° of flexion. Results were compared to the intact knee.

RESULTS

ACL resection resulted in a significant increase in AT (p < 0.05) over the entire range of motion, peaking at 20° of flexion, mean difference 6.6 ± 2.25 mm (p = 0.0007). ACL-R with HG-ACL and MIT-ACL restored AT. Resection of the ALL increased IR in the fully extended knee, mean difference 2.4 ± 2.1° (p = 0.024). When compared to the intact knee and the knee after HG-ACL-R, MIT-ACL-R knee reduced IR/SPS significantly (p < 0.05) in deep flexion angles (60°-80°), peaking at 80° of flexion. The MIT-ACL-R caused significantly less VRR at 80° flexion (p = 0.02).

CONCLUSION

MIT-ACL-R restored AT equally to the HG-ACL-R. The MIT-ACL-R reduced IR and SPS in deep flexion, resulting in overconstraint. MIT-ACL-R can be used as an alternative to standard reconstruction methods.

Landing Evaluation in Soccer Players with or without Anterior Cruciate Ligament Reconstruction

The purpose of this study was to evaluate landing biomechanics in soccer players following ACLR during two landing tasks. Eighteen soccer players with an ACLR and 18 sex-matched healthy control soccer players participated in the study. Planned landing included jumping forward and landing on the force-plates, whereas unplanned landing included jumping forward to head a soccer ball and landing on the force-plates. A significant landing×group interaction was found only for knee flexion angles (p=0.002). Follow-up comparisons showed that the ACL group landed with greater knee flexion during planned landing compared with unplanned landing (p<0.001). Significant main effects of landing were found. The unplanned landing showed reduction in hip flexion (p<0.001), hip extension moments (p<0.013), knee extension moments (p<0.001), and peak pressure (p<0.001). A significant main effect for group for gastrocnemius muscle was found showing that the ACL group landed with reduced gastrocnemius activity (p=0.002). Unplanned landing showed greater injury predisposing factors compared with planned landing. The ACL group showed nearly similar landing biomechanics to the control group during both landing tasks. However, the ACL group used a protective landing strategy by reducing gastrocnemius activity.

Single-leg hop mechanics are correlated with self-reported knee function early after anterior cruciate ligament reconstruction

BACKGROUND

Biomechanical changes that persist after anterior cruciate ligament (ACL) injury may impact short- and long-term outcomes. Understanding the relationship of biomechanics during a dynamic task and patient reported function can better identify patients who are most vulnerable to sub-optimal long-term outcomes, such as osteoarthritis (OA). The purpose of this study was to determine whether hip and knee biomechanics during single-leg hop landing were significantly correlated with the Knee injury and Osteoarthritis Outcome Score (KOOS), and whether symptomatic knees displayed altered biomechanics relative to asymptomatic knees.

METHODS

Hip and knee biomechanics during the landing phase of a single-leg hop of thirty subjects with ACLR were analyzed. Subjects were also classified as symptomatic or asymptomatic based on their KOOS results. Correlation analyses and group comparisons between symptomatic and asymptomatic subjects were conducted.

FINDINGS

KOOS Symptoms, Pain, and Sport subscales were significantly correlated with frontal and sagittal plane hip and knee biomechanics. Furthermore, those with symptomatic knees demonstrated greater hip and knee flexion angles, and greater hip flexion moments.

INTERPRETATION

These results indicate that biomechanics associated with ACLR during a single-leg hop are correlated with worse KOOS outcomes. However, these correlations may be due to symptoms of the recovery from ACLR rather than those of OA. The results of this study may help to identify rehabilitation opportunities for patients at risk for worse long-term outcomes after ACLR.

The Locations of Anterior Cruciate Ligament Tears in Pediatric and Adolescent Patients: A Magnetic Resonance Study

BACKGROUND

Recently, a resurgence of interest has been noted in anterior cruciate ligament (ACL) preservation in pediatric and adolescent patients. Different tear types, defined by their tear location, require different preservation techniques: proximal and distal avulsion tears can be treated with arthroscopic primary repair, whereas primary repair with biological scaffold has been proposed for midsubstance tears. The goal of this study was to assess the distribution of different tear types in pediatric and adolescent patients, as these are currently unknown.

METHODS

A retrospective search in an institutional radiographic database was performed for patients under 18.0 years undergoing knee magnetic resonance imaging (MRI) for ACL tears between June 2005 and June 2016. Patients with reports of chronic tears, partial tears, and multiligamentous injuries were excluded.Tear locations were graded using MRI as: proximal avulsion (distal remnant length >90% of total length; type I), proximal (75% to 90%; type II), midsubstance (25% to 75%; type III), distal (10% to 25%; type IV), and distal avulsion (<10%; type V).

RESULTS

A total of 274 patients (59% girls; mean±SD age, 15.1±2.1 y; range, 6.9 to 18.0 y) were included. Frequency of type I tears was 15%, type II 23%, type III 52%, type IV 1%, and type V 8% (of which 7% had bony avulsion).Prevalence of tear types varied with age. At age 6 to 10 years, 93% were type V (bony) avulsion tears. At age 11 to 13 years, 32% were type I, 16% type II, 32% type III, and 16% type V. At age 14 to 17 years, type III tears were more common (57%) than type I (14%), type II (25%) and type V (2%) tears.

CONCLUSIONS

It was noted that the ACL was torn at different locations depending on the patients' age. These data provide more information on the potential application for ACL preservation in pediatric and adolescent patients. Future studies correlating these findings with arthroscopy are needed before using MRI for preoperative planning of ACL preservation surgery.

LEVEL OF EVIDENCE

Diagnostic level III.

ACL reconstruction with lateral plasty reduces translational and rotatory laxity compared to anatomical single bundle and non-anatomical double bundle surgery: An in vivo kinematic evaluation with navigation system

BACKGROUND

Significantly better stability may be achieved with a Single Bundle Lateral Plasty (SBLP) reconstruction compared with the Single Bundle (SB) and Double Bundle (DB) procedures.

METHODS

The study included 42 patients who underwent ACL reconstruction. Patients were randomly selected for one of the following surgical procedure defining three study groups: Single-Bundle-Lateral-Plasty, Single-Bundle and Double-Bundle procedures. Laxity evaluation was performed with an intraoperative navigation system. Lachman test (AP30), Drawer test (AP90), Varus-Valgus stress test at 0° and 30° knee flexion (VV0, VV30), Internal-External rotation (IE30, IE90), and pivot shift (PS) test are the clinical test executed for the laxity evaluation. Laxity reduction was defined as the difference between laxity before the fixation of the graft used for the reconstruction and the laxity just after its fixation.

FINDINGS

For all the analyzed surgical techniques, the pre-reconstruction laxity values were statistically higher (P < 0.05) than the post-reconstruction values for all the analyzed tests. The analysis of the Drawer test and Internal-External rotation at 30° and 90° of knee flexion, highlighted a significant difference at time zero after surgery among the three study groups. The results showed that the SBLP technique had the highest reduction values compared to SB (P_IE90 = 0.001) and DB (P_AP90 = 0.012; P_IE30 = 0.021; P_IE90 = 0.003) techniques.

INTERPRETATION

SBLP technique showed significantly superior results in terms of antero-posterior and internal-external laxity reduction at time-zero after ACL reconstruction.

Tibiofemoral joint structural change from 2.5 to 4.5 years following ACL reconstruction with and without combined meniscal pathology

Background

People who have had anterior cruciate ligament reconstruction (ACLR) are at a high risk of developing tibiofemoral joint (TFJ) osteoarthritis (OA), with concomitant meniscal injury elevating this risk. This study aimed to investigate OA-related morphological change over 2 years in the TFJ among individuals who have undergone ACLR with or without concomitant meniscal pathology and in healthy controls. A secondary aim was to examine associations of baseline TFJ cartilage defects and bone marrow lesions (BML) scores with tibial cartilage volume change in ACLR groups.

Methods

Fifty seven ACLR participants aged 18–40 years (32 isolated ACLR, 25 combined meniscal pathology) underwent knee magnetic resonance imaging (MRI) 2.5 and 4.5 years post-surgery. Nine healthy controls underwent knee MRI at the ~ 2-year intervals. Tibial cartilage volume, TFJ cartilage defects and BMLs were assessed from MRI.

Results

For both ACLR groups, medial and lateral tibial cartilage volume increased over 2 years (P <  0.05). Isolated ACLR group had greater annual percentage increase in lateral tibial cartilage volume compared with controls and with the combined group (P = 0.03). Cartilage defects remained unchanged across groups. Both ACLR groups showed more lateral tibia BML regression compared with controls (P = 0.04). Baseline cartilage defects score was positively associated with cartilage volume increase at lateral tibia (P = 0.002) while baseline BMLs score was inversely related to medial tibia cartilage volume increase (P = 0.001) in the pooled ACLR group.

Conclusions

Tibial cartilage hypertrophy was apparent in ACLR knees from 2.5 to 4.5 years post-surgery and was partly dependent upon meniscal status together with the nature and location of the underlying pathology at baseline. Magnitude and direction of change in joint pathologies (i.e., cartilage defects, BMLs) were less predictable and either remained stable or improved over follow-up.

Electronic supplementary material

The online version of this article (10.1186/s12891-019-2687-9) contains supplementary material, which is available to authorized users.

Effectiveness of Reconstruction of the Anterior Cruciate Ligament with Quadrupled Hamstrings and Bone-Patellar Tendon-Bone Autografts

Background

The 2 most frequently used autografts for anterior cruciate ligament reconstruction are the bone-patellar tendon-bone and the quadrupled hamstrings tendon.

Hypothesis

Hamstring tendon graft is superior to patellar tendon graft in restoring tibial rotation during highly demanding activities because of its superiority in strength and linear stiffness and because it is closer morphologically to the anatomy of the natural anterior cruciate ligament.

Study Design

Case control study; Level of evidence, 3.

Methods

Eleven patients with patellar tendon graft anterior cruciate ligament reconstruction, 11 patients with hamstring tendon graft anterior cruciate ligament reconstruction, and 11 controls were assessed. Kinematic data were collected (50 Hz) with a 6-camera optoelectronic system while the subjects descended stairs and, immediately after, pivoted on their landing leg. The dependent variable examined was the tibial internal-external rotation during pivoting. All patients in both groups were also assessed clinically and with the use of a KT-1000 arthrometer to evaluate anterior tibial translation.

Results

The results demonstrated that reconstructions with either graft successfully restored anterior tibial translation. However, both anterior cruciate ligament reconstruction groups had significantly increased tibial rotation when compared with the controls, whereas no differences were found between the 2 reconstructed groups.

Conclusion

The 2 most frequently used autografts for anterior cruciate ligament reconstruction cannot restore tibial rotation to normal levels.

Clinical Relevance

New surgical techniques are needed that can better approximate the actual anatomy and function of the anterior cruciate ligament.

A non-invasive biomechanical device to quantify knee rotational laxity: Verification of the device in human cadaveric specimens

BACKGROUND

Biomechanical measurement tools have been developed and widely used to precisely quantify knee anterior-posterior laxity after anterior cruciate ligament (ACL) injury. However, validated objective device to document knee rotational laxity, though being developed by different researchers, are not yet widely used in the daily clinical practice. A new biomechanical device was developed to quantify knee internal and external rotations.

METHODS

The reliability of the new biomechanical device which measures knee rotations were tested. Different torques (1-10Nm) were applied by the device to internally and externally rotate human cadaveric knees, which were held in a flexion angle of 30°. The rotations were measured by the device in degrees. There were two independent testers, and each tester carried out three trials. Intra-rater and inter-rater reliability were quantified in terms of intraclass correlation (ICC) coefficient among trials and between testers. The device was verified by the comparison with a computer assisted navigation system. ICC was measured. Mean, standard deviation and 95% confident interval of the difference as well as the root mean square difference were calculated. The correlations were deemed to be reliable if the ICC was above 0.75.

RESULTS

The intra-rater and inter-rater reliability achieved high correlation for both internal and external rotation, ranged from 0.959 to 0.992. ICC between the proposed meter and the navigation system for both internal and external rotation was 0.78. The mean differences were 2.3° and 2.5° for internal and external rotation respectively.

CONCLUSIONS

A new knee rotational laxity meter was proposed in this study. Its reliability was verified by showing high correlation among trials. It also showed good correlation to a gold standard of measurement. It might be used to document knee rotational laxity for various purposes, especially after ACL injury, after further validation of the device in human subjects.

An Abnormal Tibial Position Is Associated With Alterations in the Meniscal Matrix: A 3-Year Longitudinal Study After Anterior Cruciate Ligament Reconstruction

Background:

An altered tibial position is still present despite anterior cruciate ligament (ACL) reconstruction. It has been demonstrated that an abnormal tibial position after an ACL injury may play a role in subsequent injuries to the meniscus, which can lead to early cartilage degeneration.

Purpose:

To determine changes in both the tibial position and the meniscal matrix present before and after ACL reconstruction as well as to evaluate the association between these 2 variables in ACL-injured knees 3 years after reconstruction.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

Bilateral knee magnetic resonance imaging (MRI) of 32 patients with unilateral ACL injuries was performed before reconstruction; 13 control participants also underwent MRI. Follow-up MRI was performed up to 3 years after surgery. Tibial position, internal tibial rotation, and T1ρ and T2 values of the menisci were calculated using an in-house MATLAB program. Student t tests and multiple linear regression were used to compare differences between injured, uninjured, and control knees as well as to assess correlations between the tibial position at 3 years and 3-year changes in quantitative MRI meniscal relaxation values.

Results:

The tibial position of injured knees was more anterior than that of uninjured knees at baseline, 6 months, and 1, 2, and 3 years (P < .05 for all). The T1ρ and T2 values of the menisci of injured knees were greater than those of uninjured and control knees in the posterior lateral and posterior medial horns up to 1 and 2 years after surgery, respectively (P < .05 for all). The tibial position at 3 years was associated with increased T2 values from baseline to 3 years in the posterior medial horn (β = 0.397; P = .031) and anterior medial horn (β = 0.360; P = .040).

Conclusion:

Results of the current study indicate that there is a persistently altered tibial position after ACL reconstruction. Initial preoperative meniscal abnormalities show prolonged but gradual improvement. Additionally, correlations between the tibial position and changes in the medial meniscal matrix suggest that the tibial position may play a role in the increased susceptibility to medial meniscal tears seen after reconstruction. The development of newer surgical techniques must address a persistently altered tibial position. Quantitative MRI is an effective instrument to evaluate meniscal matrix changes and can serve as an early radiological tool for meniscal injuries.

Clinical Results of Lateral Extra-Articular Tenodesis

In the anterior cruciate ligament (ACL) deficient knee, excellent outcomes are achieved in many patients with an isolated, intra-articular ACL reconstruction. Some patients, however, have ongoing instability or suffer graft rupture. Failure after ACL reconstruction is multifactorial, but residual anterolateral rotatory laxity is 1 potential contributing factor. Lateral extra-articular procedures are a heterogenous group of operations that were initially described as isolated treatments for the ACL deficient knee, and subsequently used in combination with intra-articular reconstructions. Initial observational studies were encouraging, however, comparative studies were less flattering and lead to a general abandonment of these procedures. With improved understanding of the anatomy and biomechanics of the anterolateral capsuloligamentous complex there has been a renewed interest in these procedures. Recent systematic reviews suggest efficacy of these procedures in improving rotational control, though data showing improved patient reported outcomes or reduced graft rupture rates are lacking. Preliminary results from ongoing clinical trials are supportive for lateral extra-articular tenodesis when used as an augment to modern, intra-articular ACL reconstructions in targeted, high-risk patients.

Risk factors for residual pivot shift after anterior cruciate ligament reconstruction: data from the MAKS group

PURPOSE

To investigate the risk factors for residual pivot shift test after anterior cruciate ligament (ACL) reconstruction based on a multicenter prospective cohort study.

METHODS

This study included patients who were registered in the Multicenter Arthroscopic Knee Surgery Study, a prospective longitudinal multicenter cohort study, and who underwent primary ACL reconstruction using autologous hamstring tendon graft between 2013 and 2016. The exclusion criteria included prior injuries or surgeries in the contralateral knee, prior ligamentous injuries in the involved knee, grade 2 or 3 concomitant ligament injuries, and inflammatory or other forms of osteoarthritis. Data from the preoperative period and at 1-year follow-up were used for further analysis, and patients with incomplete data, re-injury and loss to follow-up were also excluded. Logistic regression analysis was conducted with age, gender, Lachman test, pivot shift test, KT measurement, hyperextension, single-bundle vs. double-bundle, meniscus injury sites, and meniscus treatments as the independent variables, and postoperative pivot shift test was used as the dependent variable.

RESULTS

Three hundred and sixty-eight patients were included in the study. Hyperextension knee (P = 0.025) and a preoperative pivot shift test under anesthesia (P = 0.040) were identified as risk factors for a postoperative pivot shift via logistic regression analysis. There were no statistically significant differences in the other variables.

CONCLUSIONS

The results from a multicenter cohort study indicated that knee hyperextension and greater preoperative pivot shift under anesthesia were risk factors for residual pivot shift at 1 year after ACL reconstruction. In cases with a preoperative high-grade pivot shift and knee hyperextension, additional anterolateral structure augmentation might be considered in order to eliminate pivot shift and eventually obtain better outcomes after ACL reconstruction.

LEVEL OF EVIDENCE

II.

Is anterolateral ligament rupture a reason for persistent rotational instability after anterior cruciate ligament reconstruction?

BACKGROUND

The aim of the present study was to evaluate the clinical role of anterolateral ligament (ALL) rupture and its impact on rotational stability by comparing the clinical results and rotational stability between reconstructed anterior cruciate ligament (ACL) with intact ALL knees and reconstructed ACL with ALL injured knees.

METHODS

A total of 69 patients who had undergone surgery for ACL reconstruction and had received a minimum of two years of follow-up were included. Patients were divided into two groups with respect to the presence of ALL rupture on knee magnetic resonance imaging. Patients were assessed preoperatively and at final follow-up with physical examination findings and functional outcomes. Rotational stability was measured by a non-invasive rotameter-like device at the final follow-up at different torque values of 5 Nm (newton metres), 10 Nm and 15 Nm, and compared between the two groups.

RESULTS

The ALL was considered to be ruptured in 45 cases, named Group I (65.2%). The ALL was considered to be intact in 24 cases, named Group II (34.8%). No significant difference was found between the groups regarding the improvement of the clinical scores and physical examination findings (P > 0.05). Group I showed significantly higher internal rotation difference compared with Group II in all torque values (P < 0.05).

CONCLUSION

The difference found on rotational measurement is possibly under the value of minimal clinical important difference and does not have a clinical effect, therefore ALL reconstruction is not recommended as a standard treatment in all patients.

Modified Lemaire extra-articular stabilisation of the knee for the treatment of anterolateral instability combined with diffuse pigmented villonodular synovitis: a case report

Background

Diffuse pigmented villonodular synovitis (PVNS) of the knee is a rare proliferative joint disease associated with high recurrence rates following surgical treatment. Intra-articular joint instability in conjunction with PVNS implies complex reconstructive strategies due to the destructive nature of the disease.

Case presentation

Here, we present the case of a young patient with refractory PVNS and a chronic ipsilateral anterior cruciate ligament (ACL) rupture. Clinically, the patient presented with a grade 3 pivot shift phenomenon, indicating anterolateral rotational instability. Usually, PVNS implies a contraindication for ACL reconstruction due to the degenerative and pro-inflammatory joint microenvironment that is induced and maintained by PVNS. Therefore, we have performed a modified Lemaire extra-articular stabilization resulting in significant clinical improvement and subjective joint stability. In the latest follow-up examination at 12 months, the patient reported subjective joint stability and no swelling. In the clinical examination, the patient showed dynamic joint stability during walking. Additionally, the patient presented with grade 0 in pivot-shifting compared to the contralateral knee. The Lachman test exhibited no increased side-to-side difference and a firm endpoint.

Conclusions

Extra-articular anterolateral stabilisation of the knee in patients having anterolateral knee instability combined with PVNS is a safe and efficient surgical treatment option yielding significant clinical improvement as well as subjective joint stability.

No clinical differences between anteromedial portal and transtibial technique for femoral tunnel positioning in anterior cruciate ligament reconstruction: a prospective randomized, controlled trial

PURPOSE

The anteromedial (AMP) portal technique was introduced to position the femoral tunnel in anterior cruciate ligament (ACL) reconstruction to more closely replicate the original ACL footprint compared to the transtibial (TT) approach. Few randomized trials have evaluated differences in these techniques with respect to clinical outcomes. The purpose of this study was to determine if there are any differences in clinical outcome between the AMP and TT approaches.

METHODS

This is a single-blinded, prospective, randomized controlled trial. Participants were randomized to undergo ACL reconstruction using the AMP or TT approach. The primary outcome measure was the ACL quality of life (ACL-QOL), and secondary outcomes were the IKDC knee assessment, side-to-side difference in anterior-posterior knee laxity (KT-1000) and tunnel orientation (X-ray findings) at preoperative, 3, 6, 12, and 24 months postoperative. Statistical comparisons were performed using a series of t tests for independent groups with equal variance.

RESULTS

Ninety-six participants were consented and randomized between 2007 and 2011 with eight excluded postrandomization. Mean (SD) preoperative ACL-QOL was 33 (13) for TT and 36 (17) for AMP and improved significantly (p < 0.001) in both groups to 79 (18) and 78 (18) at 24 months postoperative, respectively. The preoperative median IKDC grade for both groups was C and improved similarly in both groups at 24 months (n.s.). There was no side-to-side difference in knee laxity based on KT-1000 measurements with a mean (SD) 1 (3) mm between affected and unaffected limbs in the TT group compared to 1 (3) mm for the AMP group. A significant difference was found in femoral tunnel orientation with the AMP group at 43° (7) and the TT group 58° (8) in the coronal plane (p < 0.001).

CONCLUSION

No differences in clinical outcome were found when comparing AMP to TT in primary ACL reconstruction using a STG graft. This prospective randomized controlled trial suggests surgeons can use either method without significantly compromising clinical outcome.

LEVEL OF EVIDENCE

I.

Curve analyses reveal altered knee, hip, and trunk kinematics during drop-jumps long after anterior cruciate ligament rupture

BACKGROUND

Anterior cruciate ligament (ACL) ruptures may lead to knee dysfunctions later in life. Single-leg tasks are often evaluated, but bilateral movements may also be compromised. Our aim was to use curve analyses to examine double-leg drop-jump kinematics in ACL-reconstructed, ACL-deficient, and healthy-knee cohorts.

METHODS

Subjects with unilateral ACL ruptures treated more than two decades ago (17-28years) conservatively with physiotherapy (ACL_PT, n=26) or in combination with reconstructive surgery (ACL_R, n=28) and healthy-knee controls (n=25) performed 40-cm drop-jumps. Three-dimensional knee, hip, and trunk kinematics were analyzed during Rebound, Flight, and Landing phases. Curves were time-normalized and compared between groups (injured and non-injured legs of ACL_PT and ACL_R vs. non-dominant and dominant legs of controls) and within groups (between legs) using functional analysis of variance methods.

RESULTS

Compared to controls, ACL groups exhibited less knee and hip flexion on both legs during Rebound and greater knee external rotation on their injured leg at the start of Rebound and Landing. ACL_R also showed less trunk flexion during Rebound. Between-leg differences were observed in ACL_R only, with the injured leg more internally rotated at the hip. Overall, kinematic curves were similar between ACL_R and ACL_PT. However, compared to controls, deviations spanned a greater proportion of the drop-jump movement at the hip in ACL_R and at the knee in ACL_PT.

CONCLUSIONS

Trunk and bilateral leg kinematics during double-leg drop-jumps are still compromised long after ACL-rupture care, independent of treatment. Curve analyses indicate the presence of distinct compensatory mechanisms in ACL_PT and ACL_R compared to controls.

Hip and Knee Kinematics and Kinetics During Landing Tasks After Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-Analysis

OBJECTIVE

  To evaluate the current evidence concerning kinematic and kinetic strategies adopted during dynamic landing tasks by patients with anterior cruciate ligament reconstruction (ACLR).

DATA SOURCES

  PubMed, Web of Science.

STUDY SELECTION

  Original research articles that evaluated kinematics or kinetics (or both) during a landing task in those with a history of ACLR were included.

DATA EXTRACTION

  Methodologic quality was assessed using the modified Downs and Black checklist. Means and standard deviations for knee or hip (or both) kinematics and kinetics were used to calculate Cohen d effect sizes and corresponding 95% confidence intervals between the injured limb of ACLR participants and contralateral or healthy matched limbs. Data were further stratified by landing tasks, either double- or single-limb landing. A random-effects-model meta-analysis was used to calculate pooled effect sizes and 95% confidence intervals.

DATA SYNTHESIS

  The involved limbs of ACLR patients demonstrated clinically and significantly lower knee-extension moments during double-legged landing compared with healthy contralateral limbs and healthy control limbs (Cohen d range = -0.81 to -1.23) and decreased vertical ground reaction forces when compared with healthy controls, regardless of task (Cohen d range = -0.39 to -1.75).

CONCLUSIONS

  During single- and double-legged landing tasks, individuals with ACLR demonstrated meaningful reductions in injured-limb knee-extension moments and vertical ground reaction forces. These findings indicate potential unloading of the injured limb after ACLR, which may have significant implications for secondary ACL injury and long-term joint health.

Rotational Laxity Control by the Anterolateral Ligament and the Lateral Meniscus Is Dependent on Knee Flexion Angle: A Cadaveric Biomechanical Study

BACKGROUND

Injury to the anterolateral ligament (ALL) has been reported to contribute to high-grade anterolateral laxity after anterior cruciate ligament (ACL) injury. Failure to address ALL injury has been suggested as a cause of persistent rotational laxity after ACL reconstruction. Lateral meniscus posterior root (LMPR) tears have also been shown to cause increased internal rotation of the knee.

QUESTIONS/PURPOSES

The purpose of this study was to determine the functional relationship between the ALL and LMPR in the control of internal rotation of the ACL-deficient knee. Specifically: (1) We asked if there was a difference in internal rotation among: the intact knee; the ACL-deficient knee; the ACL/ALL-deficient knee; the ACL/LMPR-deficient knee; and the ACL/ALL/LMPR-deficient knee. (2) We also asked if there was a difference in anterior translation among these conditions.

METHODS

Sixteen fresh frozen cadaveric knee specimens (eight men, mean age 79 years) were potted into a hip simulator (femur) and a 6 degree-of-freedom load cell (tibia). Rigid optical trackers were inserted into the proximal femur and distal tibia, allowing for the motion of the tibia with respect to the femur to be tracked during biomechanical tests. A series of points on the femur and tibia were digitized to create bone coordinate systems that were used to calculate internal rotation and anterior translation. Biomechanical testing involved applying a 5-Nm internal rotation moment to the tibia from full extension to 90° of flexion. Anterior translation was performed by applying a 90-N anterior load using a tensiometer. Both tests were performed in 15° increments tested sequentially in the following conditions: (1) intact; and (2) ACL injury (ACL-). The specimens were then randomized to either have the ALL sectioned (3) first (M+/ALL-); or (4) the LMPR sectioned first (M-/ALL+) followed by the other structure (M-/ALL-). A one-way analysis of variance was performed for each sectioning condition at each angle of knee flexion (α = 0.05).

RESULTS

At 0° of flexion there was an effect of tissue sectioning such that internal rotation of the M-/ALL- condition was greater than ACL- by 1.24° (p = 0.03; 95% confidence interval [CI], 0.16-2.70) and the intact condition by 2.5° (p = 0.01; 95% CI, 0.69-3.91). In addition, the mean (SD) internal rotations for the M+/ALL- (9.99° [5.39°]) and M-/ALL+ (12.05° [5.34°]) were greater by 0.87° (p = 0.04; 95% CI, 0.13-3.83) and by 2.15°, respectively, compared with the intact knee. At 45° the internal rotation for the ACL- (19.15° [9.49°]), M+/ALL- (23.70° [7.00°]), and M-/ALL- (18.80° [8.27°]) conditions was different than the intact (12.78° [9.23°]) condition by 6.37° (p = 0.02; 95% CI, 1.37-11.41), 8.47° (p < 0.01; 95% CI, 3.94-13.00), and 6.02° (p = 0.01; 95% CI, 1.73-10.31), respectively. At 75° there was a 10.11° difference (p < 0.01; 95% CI, 5.20-15.01) in internal rotation between the intact (13.96° [5.34°]) and the M+/ALL- (23.22° [4.46°]) conditions. There was also a 4.08° difference (p = 0.01; 95% CI, 1.14-7.01) between the intact and M-/ALL- (18.05° [7.31°]) conditions. Internal rotation differences of 6.17° and 5.43° were observed between ACL- (16.28° [6.44°]) and M+/ALL- (p < 0.01; 95% CI, 2.45-9.89) as well as between M+/ALL- and M-/ALL- (p = 0.01; 95% CI, -8.17 to -1.63). Throughout the range of flexion, there was no difference in anterior translation with progressive section of the ACL, meniscus, or ALL.

CONCLUSIONS

The ALL and LMPR both play a role in aiding the ACL in controlling internal rotation laxity in vitro; however, these effects seem to be dependent on flexion angle. The ALL has a greater role in controlling internal rotation at flexion angles > 30^o. The LMPR appears to have more of an effect on controlling rotation closer to extension.

CLINICAL RELEVANCE

Injury to the ALL and/or LMPR may contribute to high-grade anterolateral laxity after ACL injury. The LMPR and the ALL, along with the iliotibial tract, appear to act in concert as secondary stabilizers of anterolateral rotation and could be considered as the "anterolateral corner" of the knee.

Anatomic Reconstruction of the Anterior Cruciate Ligament of the Knee With or Without Reconstruction of the Anterolateral Ligament: A Randomized Clinical Trial

BACKGROUND

Rotational instability of the knee remains an issue after anterior cruciate ligament (ACL) reconstruction. Hypothesis/Purpose: The purpose was to evaluate the subjective and objective outcomes of combined reconstruction of the ACL and anterolateral ligament (ALL) of the knee. The hypothesis was that favorable outcomes can be achieved with this surgical procedure compared with isolated anatomic reconstruction of the ACL.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 2.

METHODS

One hundred ten patients with a unilateral ACL injury and high-grade pivot shift were randomly assigned to undergo either combined ACL and ALL reconstruction (group A) or isolated ACL reconstruction (group B). Preoperative and postoperative evaluations of the patients were conducted by obtaining history details, recording physical examination findings, measuring knee laxity using the KT-1000 arthrometer, and using validated outcome scores for the knee. P < .05 was considered as the cut-off level of statistical significance. The Fisher exact and Mann-Whitney U tests were used to assess statistical significance.

RESULTS

At a mean follow-up of 27 months, 53 and 50 patients in groups A and B, respectively, were available for analysis. No statistically different outcomes were found between the 2 groups except for the KT-1000 arthrometer values. The median KT-1000 arthrometer result for combined ACL and ALL reconstruction was 1.3 mm, while the median result for isolated ACL reconstruction was 1.8 mm ( P < .001). None of the patients (n = 0; 0.0%) who underwent combined ACL and ALL reconstruction had anterior translation of greater than 5 mm at maximum pulling strength compared with their normal knees at final follow-up. On the other hand, 3 (6.0%) patients who underwent isolated ACL reconstruction had anterior translation of more than 5 mm. No serious complications were found in both groups.

CONCLUSION

Combined ACL and ALL reconstruction was found to be effective in improving subjective and objective outcomes. Nevertheless, these findings were not significantly superior to isolated ACL reconstruction except for the instrumented knee laxity testing results. This might indicate that ALL reconstruction should not be performed routinely for patients undergoing ACL reconstruction.

Combined Anatomic Reconstruction of the Anterior Cruciate and Anterolateral Ligaments Using Hamstring Graft Through a Single Femoral Tunnel and With a Single Femoral Fixation

Patients with complete anterior cruciate ligament (ACL) injury have different degrees of rotational (internal rotation) laxity. A residual pivot shift has been found to be positive in more than 15% of cases after an accurate ACL reconstruction. Improved understanding of the existence, function, and biomechanical role of the anterolateral ligament (ALL) in controlling rotational instability of the knee has redirected and refocused attention on a supplemental extra-articular reconstruction of the ALL in conjunction with the intra-articular ACL reconstruction so as to restore normal kinematics of the knee. This Technical Note describes a technique that allows for a combined ACL and ALL reconstruction using autogenous hamstring graft (semitendinosus and gracilis tendons). One femoral tunnel is used connecting the anatomic femoral attachment of the ALL on the lateral wall of the lateral femoral condyle to the anatomic femoral ACL footprint on the medial wall of the lateral femoral condyle. The remaining part of the graft is fixed to the proximal tibia midway between Gordy's tubercle and the head of the fibula. This Technical Note describes a technique of both ACL and ALL reconstruction with a continuous hamstring graft.

Anterior cruciate ligament reconstruction and knee osteoarthritis

Anterior cruciate ligament (ACL) injury is a traumatic event that can lead to significant functional impairment and inability to participate in high-level sports-related activities. ACL reconstruction is considered the treatment of choice for symptomatic ACL-deficient patients and can assist in full functional recovery. Furthermore, ACL reconstruction restores ligamentous stability to normal, and, therefore, can potentially fully reinstate kinematics of the knee joint. As a consequence, the natural history of ACL injury could be potentially reversed via ACL reconstruction. Evidence from the literature is controversial regarding the effectiveness of ACL reconstruction in preventing the development of knee cartilage degeneration. This editorial aims to present recent high-level evidence in an attempt to answer whether ACL injury inevitably leads to osteoarthritis and whether ACL reconstruction can prevent this development or not.

Functional Bracing After Anterior Cruciate Ligament Reconstruction: A Systematic Review

INTRODUCTION

The purpose of this study was to evaluate the current literature on the use of functional knee braces after anterior cruciate ligament (ACL) reconstruction with respect to clinical and in vivo biomechanical data.

METHODS

A systematic search of both the PubMed and Embase databases was performed to identify all studies that reported clinical and/or in vivo biomechanical results of functional bracing versus nonbracing after ACL reconstruction. Extracted data included study design, surgical reconstruction techniques, postoperative rehabilitation protocols, objective outcomes, and subjective outcomes scores. The in vivo biomechanical data collected included kinematics, strength, function, and proprioception. Subjective clinical outcomes scores were collected when available. Quality appraisal analyses were performed using the Cochrane Collaboration tools for randomized and nonrandomized trials to aid in data interpretation.

RESULTS

Fifteen studies met the selection criteria (including 3 randomized trials [level II], 11 nonrandomized trials [level II], and 1 retrospective comparative study [level III]), with follow-up intervals ranging from 3 to 48 months. Most studies were designed to compare the effects of functional bracing versus nonbracing on subjective and objective results in patients who underwent previous primary ACL reconstruction. Functional bracing significantly improved kinematics of the knee joint and improved gait kinetics, although functional bracing may decrease quadriceps activation without affecting functional tests, range of motion, and proprioception. Four studies reported no differences in subjective outcomes scores with brace use; however, one study reported increased patient confidence with brace use, whereas another study reported decreased pain and quicker return to work when the brace was not used.

CONCLUSIONS

The effectiveness of postoperative functional bracing following ACL reconstruction remains elusive. Some data suggest that functional bracing may have some benefit with regard to in vivo knee kinematics and may offer increased protection of the implanted graft after ACL reconstruction without sacrificing function, range of motion, or proprioception. However, limited evidence exists supporting the use of routine functional bracing to decrease the rate of reinjury after ACL reconstruction.

Biomechanical Comparison of Anterolateral Procedures Combined With Anterior Cruciate Ligament Reconstruction

BACKGROUND

Anterolateral soft tissue structures of the knee have a role in controlling anterolateral rotational laxity, and they may be damaged at the time of anterior cruciate ligament (ACL) ruptures.

PURPOSE

To compare the kinematic effects of anterolateral operative procedures in combination with intra-articular ACL reconstruction for combined ACL plus anterolateral-injured knees.

STUDY DESIGN

Controlled laboratory study.

METHODS

Twelve cadaveric knees were tested in a 6 degrees of freedom rig using an optical tracking system to record the kinematics through 0° to 90° of knee flexion with no load, anterior drawer, internal rotation, and combined loading. Testing was first performed in ACL-intact, ACL-deficient, and combined ACL plus anterolateral-injured (distal deep insertions of the iliotibial band and the anterolateral ligament [ALL] and capsule cut) states. Thereafter, ACL reconstruction was performed alone and in combination with the following: modified MacIntosh tenodesis, modified Lemaire tenodesis passed both superficial and deep to the lateral collateral ligament, and ALL reconstruction. Anterolateral grafts were fixed at 30° of knee flexion with both 20 and 40 N of tension. Statistical analysis used repeated-measures analyses of variance and paired t tests with Bonferroni adjustments.

RESULTS

ACL reconstruction alone failed to restore native knee kinematics in combined ACL plus anterolateral-injured knees ( P < .05 for all). All combined reconstructions with 20 N of tension, except for ALL reconstruction ( P = .002-.01), restored anterior translation. With 40 N of tension, the superficial Lemaire and MacIntosh procedures overconstrained the anterior laxity in deep flexion. Only the deep Lemaire and MacIntosh procedures-with 20 N of tension-restored rotational kinematics to the intact state ( P > .05 for all), while the ALL underconstrained and the superficial Lemaire overconstrained internal rotation. The same procedures with 40 N of tension led to similar findings.

CONCLUSION

In a combined ACL plus anterolateral-injured knee, ACL reconstruction alone failed to restore intact knee kinematics. The addition of either the deep Lemaire or MacIntosh tenodesis tensioned with 20 N, however, restored native knee kinematics.

CLINICAL RELEVANCE

The current study indicates that unaddressed anterolateral injuries, in the presence of an ACL deficiency, result in abnormal knee kinematics that is not restored if only treated with intra-articular ACL reconstruction. Both the modified MacIntosh and modified deep Lemaire tenodeses (with 20 N of tension) restored native knee kinematics at time zero.

Cartilage morphology at 2-3 years following anterior cruciate ligament reconstruction with or without concomitant meniscal pathology

PURPOSE

To examine differences in cartilage morphology between young adults 2-3 years post-anterior cruciate ligament reconstruction (ACLR), with or without meniscal pathology, and control participants.

METHODS

Knee MRI was performed on 130 participants aged 18-40 years (62 with isolated ACLR, 38 with combined ACLR and meniscal pathology, and 30 healthy controls). Cartilage defects, cartilage volume and bone marrow lesions (BMLs) were assessed from MRI using validated methods.

RESULTS

Cartilage defects were more prevalent in the isolated ACLR (69 %) and combined group (84 %) than in controls (10 %, P < 0.001). Furthermore, the combined group showed higher prevalence of cartilage defects on medial femoral condyle (OR 4.7, 95 % CI 1.3-16.6) and patella (OR 7.8, 95 % CI 1.5-40.7) than the isolated ACLR group. Cartilage volume was lower in both ACLR groups compared with controls (medial tibia, lateral tibia and patella, P < 0.05), whilst prevalence of BMLs was higher on lateral tibia (P < 0.001), with no significant differences between the two ACLR groups for either measure.

CONCLUSIONS

Cartilage morphology was worse in ACLR patients compared with healthy controls. ACLR patients with associated meniscal pathology have a higher prevalence of cartilage defects than ACLR patients without meniscal pathology. The findings suggest that concomitant meniscal pathology may lead to a greater risk of future OA than isolated ACLR.

LEVEL OF EVIDENCE

III.

The Influence of Meniscal and Anterolateral Capsular Injury on Knee Laxity in Patients With Anterior Cruciate Ligament Injuries

BACKGROUND

The role of the anterolateral capsule (ALC) as a secondary restraint to quantitative rotatory laxity of patients with an anterior cruciate ligament (ACL) injury is currently debated.

PURPOSE/HYPOTHESIS

The purpose was to determine the influence of concomitant ALC injuries as well as injuries to other soft tissue structures on rotatory knee laxity in patients with an ACL injury. It was hypothesized that a concomitant ALC injury would be associated with increased rotatory knee laxity as measured during a quantitative pivot-shift test.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Forty-one patients with an ACL injury (average age, 23 ± 6.9 years) were enrolled. Two blinded musculoskeletal radiologists reviewed magnetic resonance imaging (MRI) scans for the presence of ACL injuries and concomitant soft tissue injuries including the ALC, medial collateral ligament, lateral collateral ligament, posterolateral corner, medial meniscus, and lateral meniscus. A standardized pivot-shift test was performed under anesthesia, and rotatory laxity was quantified according to anterior translation of the lateral tibial compartment during the pivot-shift maneuver. The Student t test was used to analyze the data. Statistical significance was set at P < .05.

RESULTS

A complete ACL rupture was confirmed in all of the patients. MRI evidence of an ALC injury was observed in 21 (51%) of the patients. Patients with MRI evidence of an ALC injury had significantly higher rotatory knee laxity (3.6 ± 1.5 mm) compared with those without an ALC injury (2.7 ± 1.5 mm; P = .04). Lateral and medial meniscus injuries were detected in 17 (41%) and 19 (46%) patients, respectively. Patients with MRI evidence of either a medial meniscus injury or lateral meniscus injury had significantly higher rotatory knee laxity compared with patients without these injuries (medial meniscus: 3.7 ± 1.4 mm vs 2.7 ± 1.6 mm, respectively; lateral meniscus: 3.7 ± 1.7 mm vs 2.7 ± 1.3 mm, respectively) (P = .03 for both).

CONCLUSION

MRI evidence of a concomitant injury to the ALC, medial meniscus, or lateral meniscus is associated with increased knee rotatory laxity in patients with an ACL injury. These structures may function as important secondary stabilizers in an ACL-injured knee. Careful assessment and proper treatment of injuries to these secondary stabilizers should be considered, especially in knees with a high level of the pivot shift.

Three-dimensional kinematic and kinetic analysis of knee rotational stability in ACL-deficient patients during walking, running and pivoting

Background

Anterior cruciate ligament (ACL) deficiency leads to altered stability of the knee. The purpose of this study was to compare the dynamic, rotational stability of the knee, expressed as rotational stiffness, between anterior cruciate ligament-deficient (ACLD) knees, their contralateral intact knees (ACLI) and a knee healthy control group during walking, running and 90° pivoting. We hypothesized a larger tibial internal rotation, a smaller knee joint external moment and a lower rotational stiffness in the ACLD group compared to the ACLI and the control group.

Methods

Kinematic and kinetic data were collected from both legs of 44 ACLD patients and 16 healthy controls during walking, running and a pivoting maneuver (descending a staircase and immediately pivoting 90° on the landing leg). Motion data were captured using 8 high-speed cameras and a force-plate. Reflective markers were attached to bony landmarks of the lower limb and rigid clusters on the shank and thigh (CASH model). Maximum internal tibial rotation and the corresponding rotational moment were identified for all tasks and groups and used to calculate rotational stiffness (= Δmoment /Δrotation) of the knee.

Results

The tibial internal rotation of the ACLD knee was not significantly different from the ACLI knee during all three tasks. During walking and running, the tibial rotation of the control group was significantly different from both legs of the ACL-injured patient. For pivoting, no difference in tibial rotation between knees of the ACLD, ACLI and the control group was found. Knee joint external moments were not significantly different between the three groups during walking and pivoting. During running, the moments of the ACLI group were significantly higher than both the knees of the ACLD and the control group. Rotational stiffness did not differ significantly between groups in any of the three tasks.

Conclusion

A high-intensity activity combining stair descent and pivoting produces similar angular rotations, knee joint external moments and rotational stiffness in ACLD knees compared to ACLI knees and the control group. During running, the ACLI knee displayed a higher external moment than the ACLD and the healthy control group. This could indicate some type of protective strategy or muscular adaptation in the ACL-injured patients.

Geometric Risk Factors Associated With Noncontact Anterior Cruciate Ligament Graft Rupture

BACKGROUND

Anterior cruciate ligament (ACL) graft rupture occurs at a high rate, especially in young athletes. The geometries of the tibial plateau and femoral intercondylar notch are risk factors for first-time ACL injury; however, little is known about the relationship between these geometries and risk of ACL graft rupture.

HYPOTHESIS

The geometric risk factors for noncontact graft rupture are similar to those previously identified for first-time noncontact ACL injury, and sex-specific differences exist.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Eleven subjects who suffered a noncontact ACL graft rupture and 44 subjects who underwent ACL reconstruction but did not experience graft rupture were included in the study. Using magnetic resonance imaging, the geometries of the tibial plateau subchondral bone, articular cartilage, meniscus, tibial spines, and femoral notch were measured. Risk factors associated with ACL graft rupture were identified using Cox regression.

RESULTS

The following were associated with increased risk of ACL graft injury in males: increased posterior-inferior-directed slope of the articular cartilage in the lateral tibial plateau measured at 2 locations (hazard ratio [HR] = 1.50, P = .029; HR = 1.39, P = .006), increased volume (HR = 1.45, P = .01) and anteroposterior length (HR = 1.34, P = .0023) of the medial tibial spine, and increased length (HR = 1.18, P = .0005) and mediolateral width (HR = 2.19, P = .0004) of the lateral tibial spine. In females, the following were associated with increased risk of injury: decreased volume (HR = 0.45, P = .02) and height (HR = 0.46, P = .02) of the medial tibial spine, decreased slope of the lateral tibial subchondral bone (HR = 0.72, P = .01), decreased height of the posterior horn of the medial meniscus (HR = 0.09, P = .001), and decreased intercondylar notch width at the anterior attachment of the ACL (HR = 0.72, P = .02).

CONCLUSION

The geometric risk factors for ACL graft rupture are different for males and females. For females, a decreased femoral intercondylar notch width and a decreased height of the posterior medial meniscus were risk factors for ACL graft rupture that have also been found to be risk factors for first-time injury. There were no risk factors in common between ACL graft injury and first-time ACL injury for males.

Bracing can partially limit tibial rotation during stressful activities after anterior crucial ligament reconstruction with a hamstring graft

BACKGROUND

Hamstring graft has substantial differences with BPTB graft regarding initial mechanical strength, healing sequence, and vascularization, which may imply that a different approach during rehabilitation period is required. The purpose of this study was to investigate the influence of knee bracing on tibial rotation in ACL-reconstructed patients with a hamstring autograft during high loading activities. The hypothesis was that there would be a decrease in tibial rotation in the ACL-reconstructed braced knee as compared to the unbraced knee.

METHODS

Twenty male patients having undergone unilateral ACL reconstruction with a semitendinosus/gracilis autograft were assessed. Kinematic data were collected with an eight-camera optoelectronic system during two stressful tasks: (1) descending from a stair and subsequent pivoting; and (2) landing from a platform and subsequent pivoting. In each patient, three different experimental conditions were evaluated: (A) wearing a prophylactic brace (braced condition); (B) wearing a patellofemoral brace (sleeved condition); (C) without brace (unbraced condition). The intact knee without brace served as a control.

RESULTS

Tibial rotation was significantly lower in the intact knee compared to all three conditions of the ACL-reconstructed knee (P≤0.01 for both tasks). Presence of a brace or sleeve resulted in lower tibial rotation than in the unbraced condition (p=0.003 for descending/pivot and P=0.0004 for landing/pivot). The braced condition resulted in lower rotation than the sleeved condition for descending/pivoting (P=0.031) while no differences were found for landing/pivoting (P=0.230).

CONCLUSION

Knee bracing limited the excessive tibial rotation during pivoting under high loading activities in ACL-reconstructed knees with a hamstring graft. This partial restoration of normal kinematics may have a potential beneficial effect in patients recovering from ACL reconstruction with a hamstring autograft.

LEVEL OF EVIDENCE

Level III, case-control therapeutic study.