Anterior cruciate ligament reconstruction: a new cortical suspension device for femoral fixation with transtibial and transportal techniques

Anterior cruciate ligament reconstruction learning curve study - Comparison of the first 50 consecutive patients of five orthopaedic surgeons during a 5-year follow-up

BACKGROUND

The goal of all surgical and orthopaedic training is to ensure necessary education and surgical skills without compromising the quality of operations or patient safety. Anterior cruciate ligament reconstruction (ACLR) is a common multi-staged orthopaedic surgical procedure with a learning curve. Previous studies focus mainly on learning or the learning curve of one surgeon and tunnel placements. The aims of this study were to define the learning curve in arthroscopic ACLRs, define the number of procedures needed before the surgical "knifetime" plateaus, examine the effect of experience on complications, and identify possible individual differences in the surgical learning curve.

METHODS

The study included the first 50 consecutive ACLR operations of five orthopaedic surgeons, thus, a total of 250 patients. For comparison and statistical analysis, patients were arranged into five groups, each comprising 50 patients (=order group). Order group 1 comprised the first 10 patients operated on by each of the five surgeons, group 2 patients 11-20, group 3 patients 21-30, group 4 patients 31-40, and group 5 the last 10 patients. The learning curve was defined with a LOESS curve. Surgical time and complications, including graft failure and postoperative knee instability, were analysed between order groups and between surgeons.

RESULTS

Median surgical time was 105 (interquartile range 82-124) min. The learning curve showed the first steep decline in surgical time and started to settle slowly after 20 reconstructions. Surgical time was significantly longer when order group 1 was compared with order group 2 (p = 0.031), and when order group 1 was compared separately with order groups 3, 4, and 5 (p < 0.001). Operation order alone explained only 17.1% of the alteration in surgical time. No significant difference emerged in graft failure rate between the order groups or the surgeons. Objective instability of the knee showed a significant difference when order group 1 was compared separately with order group 3 and with order group 4 (p = 0.004). Surgical time differed between surgeons (p < 0.001), and the shape of the learning curve showed great individual variability.

CONCLUSION

In the first 10 to 20 ACLR operations, the surgical time was longer and the complication rate higher, but thereafter both started to settle down. We recommend that first 10-20 ACLR operations should be supervised.

Anteromedial Portal Technique, but Not Outside-in Technique, Is Superior to Standard Transtibial Technique in Knee Stability and Functional Recovery After Anterior Cruciate Ligament Reconstruction: A Network Meta-analysis

PURPOSE

To compare the postoperative outcomes of 4 different femoral drilling techniques in anterior cruciate ligament reconstruction.

METHODS

Three databases were searched for randomized controlled trials comparing any 2 or more of the following femoral drilling techniques in anterior cruciate ligament reconstruction: standard transtibial (sTT), anteromedial portal (AMP), outside-in (OI), or modified transtibial (mTT) technique. A Bayesian network meta-analysis was performed to assess postoperative stability and functional recovery in terms of the side-to-side difference (measured by arthrometry), Lachman test, pivot-shift test, International Knee Documentation Committee subjective and objective scores, Lysholm score, and Tegner score. The Fisher exact probability test and χ2 test were used to compare the incidences of infection and graft rupture, respectively.

RESULTS

We included 20 randomized controlled trials involving 1,515 patients. The AMP technique showed a lower side-to-side difference (standardized mean difference, -0.33; 95% credible interval [CrI], -0.53 to -0.12), higher negative rate on the pivot-shift test (odds ratio, 2.19; 95% CrI, 1.38 to 3.44), and higher International Knee Documentation Committee objective score (odds ratio, 3.13; 95% CrI, 1.42 to 7.82) than the sTT technique. However, knee stability and functional outcomes did not differ significantly between the OI and sTT techniques. Safety outcomes of the mTT technique were unavailable. The incidence of graft rupture was 5.20% for the OI technique, 2.27% for the AMP technique, and 1.51% for the sTT technique. The OI technique had a significantly higher incidence of graft rupture than the sTT technique (χ2 = 4.421, P = .035). No significant difference in the incidence of infection was found between the sTT, AMP, and OI techniques (P = .281).

CONCLUSIONS

The AMP technique, but not the OI technique, was superior to the sTT technique in knee stability and functional recovery. The OI technique had a higher incidence of graft rupture than the sTT technique. There was no significant difference between the AMP and OI techniques or between the mTT technique and any other femoral drilling technique.

LEVEL OF EVIDENCE

Level II, meta-analysis of Level I and II studies.

Transportal versus all-inside techniques of anterior cruciate ligament reconstruction: a systematic review

Background

Transportal (TP) and all-inside techniques (AIT) are the most commonly used anterior cruciate ligament (ACL) reconstruction procedures in current clinical practice. However, there is an ongoing debate over which procedure is superior. Therefore, the purpose of this systematic review was to evaluate and compare the clinical outcomes and complications of these two techniques to propose recommendations for future application. Our primary hypothesis was that AIT is a superior ACLR technique compared to TP.

Methods

A systematic literature review, using PRISMA guidelines, was conducted using PubMed, Medline, Google Scholar, and EMBASE, up to February 2021 to identify studies focusing on AIT and TP techniques of ACL reconstruction. We excluded animal experiments, cadaveric studies, retrospective studies, case reports, technical notes, and studies without quantitative data. Patients’ characteristics, surgical technical features, along with postoperative follow-up and complications were extracted and reported accordingly. Methodological quality of the included studies was assessed using the Modified Coleman Methodology Score (MCMS).

Results

A total of 44 studies were selected for this review, of which four were comparative studies. A total of 923 patients underwent AIT and 1678 patients underwent the TP technique for ACLR. A single semitendinosus graft was commonly used in the AIT compard to combined semitendinosus and gracilis graft in the TP group. The postoperative increase in International Knee Documentation Committee (IKDC), Lysholm, KT-1000, and Short Form-12 (physical and mental) scores were similar in the AIT group and the TP group. Contrastingly, the VAS pain score was significantly lower in the AIT group compared to the TP group. Furthermore, the pooled complication rates from all studies were similar between the two groups (AIT: 54 patients, 8.26% vs. PT: 55 patients, 6.62%). However, the four studies that prospectively compared AIT and TP techniques showed lesser complications in the AIT group than the TP group.

Conclusion

Since the future trend in orthopedic surgery is toward less invasive and patients’ satisfaction with good outcomes, AIT is a good alternative method considering preserving bony tissue and gracilis tendon with less post-operative pain, along with more knee flexor strength and equal outcomes compared to conventional ACL reconstruction surgery.

Level of Evidence II.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-021-02872-x.

Comparison of Clinical Outcomes between Anteromedial and Transtibial Techniques of Single-Bundle Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-Analysis

This study compared clinical outcomes obtained after single-bundle anterior cruciate ligament (ACL) reconstruction using the anteromedial (AM) and transtibial (TT) techniques, which comprise the conventional transtibial (cTT) and modified transtibial (mTT) techniques. This study included clinical randomized controlled trials and prospective and retrospective controlled trials with AM and TT techniques from the PubMed and Embase databases and the Cochrane Library. All databases were searched from January 2010 to July 2020. Two independent evaluators verified the quality of the included studies using the Cochrane Collaboration's risk of bias tool and the Newcastle-Ottawa Scale (NOS). Outcome measures analysed included the Lachman test, pivot-shift test, side-to-side difference (SSD), Lysholm score, Tegner activity scale, International Knee Documentation Committee (IKDC) grade and score. Ten randomized controlled trials (RCTs) and 16 prospective and retrospective controlled trials were included with a total of 2202 patients. There were 1180 patients and 1022 patients in the AM and TT groups, respectively. Compared to the cTT group, superior postoperative results were observed in the AM group based on the negative rate of the Lachman test and the pivot-shift test, IKDC grade and score, Lysholm score, Tegner activity scale and SSD (p < 0.05). However, there was no significant difference between the AM and mTT groups (p > 0.05). Compared to the conventional TT technique, the AM technique exhibited superior clinical outcomes. Nevertheless, the modified TT and AM techniques had comparable results. With neither of the techniques (mTT or AM) producing significantly superior outcomes, surgeons can choose either of them depending on their preferences.

Superior Postoperative Stability and Functional Outcomes With Anteromedial Versus Transtibial Technique of Single-Bundle Autologous Hamstring Anterior Cruciate Ligament Reconstruction: A Meta-analysis of Prospective Randomized Controlled Trials

PURPOSE

The aim of this meta-analysis was to compare the postoperative stability and functional outcomes of anteromedial (AM)- and transtibial (TT)-based single-bundle hamstring anterior cruciate ligament (ACL) reconstruction techniques.

METHODS

A meta-analysis comparing the outcomes of single-bundle hamstring ACL reconstruction using the AM and TT techniques was performed. Prospective randomized controlled trials identified from searches of PubMed, Cochrane, and Embase were included in this review. The outcome measures analyzed included postoperative Lachman test and pivot-shift test results, side-to-side difference, International Knee Documentation Committee (IKDC) score, Lysholm score, and Tegner activity score.

RESULTS

A total of 7 randomized controlled trials (654 patients) were included in this review. The AM technique, compared with the TT technique, resulted in superior postoperative stability based on the negative Lachman test rate (risk ratio [RR], 1.12; 95% confidence interval [CI], 1.01 to 1.24; P = .03; 95% prediction interval [PI], 0.32 to 3.46), negative pivot-shift test rate (RR, 1.16; 95% CI, 1.06 to 1.28; P = .002; 95% PI, 0.40 to 2.88), and side-to-side difference (weighted mean difference [WMD], -0.32 mm; 95% CI, -0.48 to -0.16; P < .0001; 95% PI, -0.55 to -0.09). Likewise, the AM technique contributed to superior postoperative functional outcomes based on the proportion of IKDC grade A findings (RR, 1.16; 95% CI, 1.02 to 1.32; P = .03; 95% PI, 0.40 to 2.83) and the Lysholm score (WMD, 0.82; 95% CI, 0.23 to 1.41; P = .007; 95% PI, -0.22 to 1.86). However, the AM and TT techniques had comparable subjective IKDC scores (WMD, 0.98; 95% CI, -0.91 to 2.88; P = .31; 95% PI, -3.18 to 5.14) and Tegner activity scores (WMD, 0.32; 95% CI, -0.23 to 0.86; P = .25; 95% PI, -3.84 to 4.48).

CONCLUSIONS

The AM method of single-bundle hamstring ACL reconstruction results in superior postoperative stability and functional outcomes compared with the TT method.

LEVEL OF EVIDENCE

Level I, systematic review of Level I studies.

A comparative study of a new "off-centre:off-centre" technique of transtibial ACL reconstruction with "centre:centre" transportal ACL reconstruction

BACKGROUND & INTRODUCTION

A Single Bundle ACL Reconstruction aims at placing Tibial and Femoral attachment sites of graft from Centre of Native Tibial Foot-print to Centre of Native Femoral Footprint. In tibial tunnel independent Transportal Reconstruction, where the two points are chosen separately, the objective is easily achievable. In Tibial tunnel dependent Transtibial ACL reconstruction, Capture of Centre of femoral tunnel is dictated by Trajectory of Tibial Tunnel. Heming et al. remarked that a TT technique could produce tunnel centred in the both the tibial and femoral footprint but only if a starting point "prohibitively close" to the joint line with a correspondingly short tibial tunnel were used. A new technique wherein authors aim to place the mouths of Tibial & Femoral tunnel at off-centre location, taking care to contain these tunnels still within native footprints to achieve a tunnel which is of adequate length and does not come too close to the joint and saves MCL from violation.

OBJECTIVE

To study the clinic-radiological outcome of a new "Off-centre to Off-centre" method of Transtibial Reconstruction and compare the results with "centre to centre" method of Transportal reconstruction.

METHODS

A prospective randomised comparative study of consecutive 75 clinico-radiological cases of ACL tear with definitive clinical symptoms of knee instability who underwent arthroscopic ACL reconstruction by Same Arthroscopy Surgeon was conducted between 2016 and 2018. A modification, as described herein below, was used in Transtibial technique with placement of centre of mouth of internal opening of tibial tunnel "off-centre" that allowed a predictable capture of Femoral Footprint in "off-centre" location without tunnel being too close to joint line. Only those cases were included in which the mouths of tunnel were completely contained within footprints. Capture of footprints was verified during arthroscopy. 11 cases were excluded because either the native footprint was not clearly delineated, or surgeon failed to completely contain the mouth of tunnel/socket within the delineated footprint of tibia or femur. Hence 64 patients, 32 each in Transtibial & Transportal group were enrolled into the study. The results were analysed with the objective to arrive at recommendations for improving capture of anatomical footprints at both ends by Transtibial technique.

RESULTS

There were no statistically significant differences in Clinical outcome scores. However there were statistically significant differences in length of Femoral Tunnel, Obliquity of Femoral tunnel as well as Femoral Tunnel Placements. Likewise, Tibial Tunnel Angle in AP & Lateral View as well as Tibial tunnel placement were also significantly different.

CONCLUSION

It is concluded that tunnels follow much different trajectories in the bones in two techniques and trying to apply "Centre of Tibial footprint to Centre of Femoral footprint" philosophy of Transportal technique may be imprudent for Transtibial Technique. An "Off-centre to Off-centre but contained within Footprints" may afford a more predictable and reliable capture of anatomical foot prints without any adverse effect on outcomes.

Femoral tunnel position in chronic anterior cruciate ligament rupture reconstruction: randomized controlled trial comparing anatomic, biomechanical and clinical outcomes

PURPOSE

The aim of this study was to compare the outcomes between anteromedial (AM) and transtibial (TT) femoral tunnel positioning techniques for the reconstruction of chronic anterior cruciate ligament (ACL) rupture.

MATERIALS AND METHODS

It is a randomized prospective study of 106 patients who underwent ACL reconstruction because of a chronic ACL rupture (55 AMT, 51 TT). Minimum follow-up was 2 years. Demographic, clinical and radiological data, including MRI grafts' anatomy and biomechanics intraoperative navigation system evaluation, were analyzed. Also, International Knee Documentation Committee score, Tegner Knee score, Lysholm Knee Score, Short-Form Health Survey and 4-point Likert Scale were evaluated.

RESULTS

The AM technique achieves a more anatomic graft than TT technique in both sagittal and coronal plane (6° approximately). Immediate postoperative biomechanical evaluation of the graft showed both techniques significantly improved translational and rotational laxity (p = 0.000). AMT showed superiority only in controlling internal rotation (p = 0.016). Both techniques reported significant improvement in all evaluated score scales, without differences between techniques. Independently of the femoral tunnel positioning technique, patients with cartilage lesion had worse clinical outcomes.

CONCLUSIONS

Our findings suggest that AMT achieves a more anatomical and biomechanically accurate graft allowing better control over internal rotation laxity; however, this does not lead to better clinical outcomes if we compare with TT in the reconstruction of chronic ACL rupture. Patients with chronic ACL rupture and cartilage lesion had worse clinical outcomes, independently the femoral tunnel positioning technique.

Bridge-Enhanced Anterior Cruciate Ligament Repair: Two-Year Results of a First-in-Human Study

Background

Bridge-enhanced anterior cruciate ligament repair (BEAR) combines suture repair of the anterior cruciate ligament (ACL) with a specific extracellular matrix scaffold (the BEAR scaffold) that is placed in the gap between the torn ends of the ACL to facilitate ligament healing.

Purpose/Hypothesis

The purpose of this study was to report the 12- and 24-month outcomes of patients who underwent the BEAR procedure compared with a nonrandomized concurrent control group who underwent ACL reconstruction (ACLR) with an autograft. We hypothesized that the BEAR group would have physical examination findings, patient-reported outcomes, and adverse events that were similar to those of the ACLR group.

Study Design

Cohort study; Level of evidence, 2.

Methods

Ten patients underwent BEAR, and 10 underwent ACLR with a 4-stranded hamstring autograft. At 24 months, 9 of the 10 BEAR patients and 7 of the 10 ACLR patients completed a study visit. Outcomes reported included International Knee Documentation Committee (IKDC) subjective and objective results, knee anteroposterior (AP) laxity findings via an arthrometer, and functional outcomes.

Results

There were no graft or repair failures in the first 24 months after surgery. The IKDC subjective scores in both groups improved significantly from baseline (P < .0001) at 12 and 24 months, to 84.6 ± 17.2 in the ACLR group and to 91.7 ± 11.7 in the BEAR group. An IKDC objective grade of A (normal) was found in 44% of patients in the BEAR group and in 29% of patients in the ACLR group at 24 months; no patients in either group had C (abnormal) or D (severely abnormal) grades. Arthrometer testing demonstrated mean side-to-side differences in AP laxity that were similar in the 2 groups at 24 months (BEAR, 1.94 ± 2.08 mm; ACLR, 3.14 ± 2.66 mm). Functional hop testing results were similar in the 2 groups at 12 and 24 months after surgery. Hamstring strength indices were significantly higher in the BEAR group compared with the ACLR group (P = .0001).

Conclusion

In this small, first-in-human study, BEAR produced similar outcomes to ACLR with a hamstring autograft. BEAR may result in knee stability and patient-reported outcomes at 2 years sufficient to warrant longer term studies of efficacy in larger groups of patients.

An animal model of reconstruction of single femoral tunnel with single bone bi-quadruple ACL and internal fixation

We introduced several variables in an animal model of anterior cruciate ligament (ACL) reconstruction to determine the best parameters for surgery in humans. We divided 130 LYD pigs into two groups depending on whether the femoral tunnel goes through the medial tibial tunnel or through the medial fossa of the knee joint. Each subgroup was further divided. Four weeks after surgery the knee specimens were examined for passive flexion and extension test. No group showed a creep effect. In the biomechanical tests, we recorded maximal strength, maximum load, and stiffness parameters. The 100° + 1.0 mm, 1.5 mm, and 2.0 mm positions of the tibial tunnel group, and 10.5 (1.5) + 1.0 mm, 1.5 mm, and 2.0 mm positions of the knee joint cavity group had better biomechanical effects, histocompatibility and revascularization in ACL reconstruction. Overall, these results demonstrated significant differences in the effectiveness of ACL reconstruction based on several surgical parameters, which should contribute to establishing a gold standard for ACL surgery in patients.

Anteromedial versus transtibial technique in single-bundle autologous hamstring ACL reconstruction: a meta-analysis of prospective randomized controlled trials

BACKGROUND

The aim of this study was to compare the clinical outcome and postoperative complication between single-bundle anterior cruciate ligament (ACL) reconstruction with an anteromedial (AM) technique and a transtibial (TT) technique.

METHODS

The study includes clinical randomized controlled trials comparing the clinical outcomes of ACL reconstruction using the autologous hamstring tendon with an AM method and a TT method published up to September 2017 were retrieved from PubMed, Cochrane Library, and Embase databases. Relevant data were extracted and the Physiotherapy Evidence Database (PEDro) scale was used to assess the methodological quality. Stata/SE 12.0 was used to perform a meta-analysis of the clinical outcome.

RESULTS

Five RCTs were included, with a total of 479 patients: 239 patients and 240 patients in the AM group and the TT group, respectively. Assessing postoperative stability, better results were found in the AM group for the negative rate of the Lachman test (P < 0.05), the negative rate of the pivot-shift test (P < 0.05) and the side-to-side difference (P < 0.05). Assessing postoperative functional outcome, the AM group yielded superior results in proportion with International Knee Documentation Committee (IKDC) grade A (P < 0.05) and the Lysholm scores (P < 0.05) but had a comparable IKDC score (P > 0.05). In terms of postoperative complication, no significant difference was found between the AM group and the TT group (P > 0.05).

CONCLUSIONS

The outcome of single-bundle ACL reconstruction with the AM technique is better than that with the TT technique in terms of postoperative stability and functional recovery of the knee.

The influence of femoral tunnel length on graft rupture after anterior cruciate ligament reconstruction

Background

For ACL reconstruction, the minimum length of the femoral tunnel and the flexor tendon graft length needed within the tunnel for proper integration have not been defined. The aim of this study was to assess whether a short tunnel is a risk factor for poor prognosis and re-rupture by comparing the outcomes of patients with short femoral tunnels to those of patients with longer tunnels.

Materials and methods

A retrospective observational study of 80 patients who underwent ACL reconstruction using flexor tendons via the medial transportal or transtibial technique was performed. Patients were categorized according to the amount of graft within the tunnel: ≤1.5 versus >1.5 cm; ≤2 versus >2 cm; ≤2.5 versus >2.5 cm; and ≤1.5 versus >2.5 cm. Patients were evaluated 2 years after surgery by performing a physical examination (Lachman, pivot shift and anterior drawer tests), using a KT1000 arthrometer, calculating objective and subjective International Knee Documentation Committee scores, conducting the Lysholm score, and recording re-ruptures.

Results

Of the 80 operated patients, nine were lost to follow-up. Comparative assessment of the patients with different amounts of graft within the tunnel indicated no significant differences in the evaluated outcomes, except for positive Lachman test results, which were more frequent in patients with tunnels with ≤2 cm of graft than in those with tunnels with >2 cm of graft.

Conclusion

The amount of graft within the femoral tunnel does not appear to be a risk factor for clinical instability of the knee or re-rupture of the graft. Level of evidence: case series, level IV.

Level of evidence

Case series, level IV.

Current Trends in Anterior Cruciate Ligament Reconstruction: A Review

Anterior cruciate ligament reconstruction (ACLR) is an accepted and established surgical technique for anterior cruciate ligament (ACL) injuries and is now being practiced across the globe in increasing numbers. Although most patients get good to excellent results in the short-term after ACLR, its consequences in the long-term in prevention or acceleration of knee osteoarthritis (OA) are not yet well-defined. Still, there are many debatable issues related to ACLR, such as the appropriate timing of surgery, graft selection, fixation methods of the graft, operative techniques, rehabilitation after surgery, and healing augmentation techniques. Most surgeons prefer not to wait long after an ACL injury to do an ACLR, as delayed reconstruction is associated with secondary damages to the intra- and periarticular structures of the knee. Autografts are the preferred choice of graft in primary ACLR, and hamstring tendons are the most popular amongst surgeons. Single bundle ACLR is being practiced by the majority, but double bundle ACLR is getting popular due to its theoretical advantage of providing more anatomical reconstruction. A preferred construct is the interference fixation (Bio-screw) at the tibial site and the suspensory method of fixation at the femoral site. In a single bundle hamstring graft, a transportal approach for creating a femoral tunnel has recently become more popular than the trans-tibial technique. Various healing augmentation techniques, including the platelet rich plasma (PRP), have been tried after ACLR, but there is still no conclusive proof of their efficacy. Accelerated rehabilitation is seemingly more accepted immediately after ACLR.

Enhanced Bone-Tendon-Bone Approach for Open Anterior Cruciate Ligament Replacement With Conservation of the Joint Capsule

Arthroscopic procedures for ruptured anterior cruciate ligament (ACL) tears are a common standard. However, there are strong alternatives to this standard. The purpose of this study is to present a precise, fast, and minimally invasive but open procedure for reconstruction of the ruptured ACL. The torn ACL is substituted by a widely used bone-patellar tendon-bone (BPTB) autograft. After the BPTB graft has been harvested, the Hoffa body is exposed and mobilized ventrally. The surgeon then has a free view of the remnants of the torn ACL, which are to be removed completely. Through the tibial and femoral footprints of the ACL, a tunnel is drilled under a direct view, thus ensuring optimal anatomic positioning of the BPTB graft. The described approach is simple in handling and advantageous because all steps are performed under a direct view, which improves overall precision and intraoperative functional control.