Biomechanical Comparison of Single-Bundle and Double-Bundle Posterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-Analysis

Altered knee kinematics after posterior cruciate ligament single-bundle reconstruction-a comprehensive prospective biomechanical in vivo analysis

Purpose: Passive tibiofemoral anterior-posterior (AP) laxity has been extensively investigated after posterior cruciate ligament (PCL) single-bundle reconstruction. However, the PCL also plays an important role in providing rotational stability in the knee. Little is known in relation to the effects of PCL single-bundle reconstruction on passive tibiofemoral rotational laxity. Gait biomechanics after PCL reconstruction are even less understood. The aim of this study was a comprehensive prospective biomechanical in vivo analysis of the effect of PCL single-bundle reconstruction on passive tibiofemoral rotational laxity, passive anterior-posterior laxity, and gait pattern. Methods: Eight patients undergoing PCL single-bundle reconstruction (seven male, one female, mean age 35.6 ± 6.6 years, BMI 28.0 ± 3.6 kg/m2) were analyzed preoperatively and 6 months postoperatively. Three of the eight patients received additional posterolateral corner (PLC) reconstruction. Conventional stress radiography was used to evaluate passive translational tibiofemoral laxity. A previously established rotometer device with a C-arm fluoroscope was used to assess passive tibiofemoral rotational laxity. Functional gait analysis was used to examine knee kinematics during level walking. Results: The mean side-to-side difference (SSD) in passive posterior translation was significantly reduced postoperatively (12.1 ± 4.4 mm vs. 4.3 ± 1.8 mm; p < 0.01). A significant reduction in passive tibiofemoral rotational laxity at 90° knee flexion was observed postoperatively (27.8° ± 7.0° vs. 19.9° ± 7.5°; p = 0.02). The range of AP tibiofemoral motion during level walking was significantly reduced in the reconstructed knees when compared to the contralateral knees at 6-month follow-up (16.6 ± 2.4 mm vs. 13.5 ± 1.6 mm; p < 0.01). Conclusion: PCL single-bundle reconstruction with optional PLC reconstruction reduces increased passive tibiofemoral translational and rotational laxity in PCL insufficient knees. However, increased passive tibiofemoral translational laxity could not be fully restored and patients showed altered knee kinematics with a significantly reduced range of tibiofemoral AP translation during level walking at 6-month follow-up. The findings of this study indicate a remaining lack of restoration of biomechanics after PCL single-bundle reconstruction in the active and passive state, which could be a possible cause for joint degeneration after PCL single-bundle reconstruction.

A Comprehensive Meta-analysis of Clinical and Biomechanical Outcomes Comparing Double-Bundle and Single-Bundle Posterior Cruciate Ligament Reconstruction Techniques

BACKGROUND

Posterior cruciate ligament (PCL) reconstruction techniques have historically focused on single-bundle (SB) reconstruction of the larger anterolateral bundle without addressing the codominant posteromedial bundle. The SB technique has been associated with residual laxity and instability, leading to the development of double-bundle (DB) reconstruction techniques.

PURPOSE

To perform a meta-analysis of comparative clinical and biomechanical studies to differentiate the pooled outcomes of SB and DB PCL reconstruction cohorts.

STUDY DESIGN

Meta-analysis and systematic review: Level of evidence, 3.

METHODS

Six databases were queried in February 2022 for literature directly comparing clinical and biomechanical outcomes for patients or cadaveric specimens undergoing DB PCL reconstruction against SB PCL reconstruction. Biomechanical outcomes included posterior tibial translational laxity, external rotational laxity, and varus laxity at 30° and 90° of knee flexion. Clinical outcomes included the side-to-side difference in posterior tibial translation during postoperative stress radiographs, risk of a major complication, and the following postoperative patient-reported outcome measures: Lysholm, Tegner, and International Knee Documentation Committee (IKDC) subjective and objective scores. A random-effects model was used to compare pooled clinical and biomechanical outcomes between the cohorts.

RESULTS

Fifteen biomechanical studies and 13 clinical studies were included in this meta-analysis. The DB group demonstrated significantly less posterior tibial translation at 30° and 90° of knee flexion (P < .00001). Additionally, the DB group demonstrated significantly less external rotation laxity at 90° of knee flexion (P = .0002) but not at 30° of knee flexion (P = .33). There was no difference in varus laxity between the groups at 30° (P = .56) or 90° (P = .24) of knee flexion. There was significantly less translation on stress radiographs in the DB group (P = .02). Clinically, there was no significant difference between the groups for the Lysholm score (P = .95), Tegner score (P = .14), or risk of a major complication (P = .93). DB PCL reconstruction led to significantly higher odds of achieving "normal" or "near normal" objective IKDC outcomes for the included prospective studies (P = .04) and higher subjective IKDC scores (P = .01).

CONCLUSION

DB PCL reconstruction leads to superior biomechanical outcomes and clinical outcomes relative to SB PCL reconstruction. Re-creating native anatomy during PCL reconstruction maximizes biomechanical stability and clinical outcomes.

Comparison of Posterior Cruciate Ligament Reconstruction Using an All-Inside Technique With and Without Independent Suture Tape Reinforcement

Background

Biomechanical studies support the use of suture tape reinforcement for limiting graft elongation and increasing strength in knee ligament reconstructions.

Purpose

To compare posterior cruciate ligament (PCL) laxity, complication and reoperation rates, and patient-reported outcomes (PROs) after all-inside single-bundle PCL reconstruction (PCLR) with versus without independent suture tape reinforcement.

Study Design

Cohort study; Level of evidence, 3.

Methods

A retrospective cohort study of consecutive patients who underwent primary, all-inside allograft single-bundle PCLR with and without independent suture tape reinforcement at a single academic institution from 2012 to 2019. Medical records were reviewed for patient characteristics, additional injuries, and concomitant procedures. PRO scores (including the International Knee Documentation Committee [IKDC], Tegner activity scale, and Lysholm scores), bilateral comparison kneeling radiographs, and physical examination findings were collected at a minimum of 2 years postoperatively.

Results

Included were 50 patients: 19 with suture tape reinforcement (mean age 30.6 ± 2.9 years) and 31 without suture tape reinforcement (control group; mean age 26.2 ± 1.6 years). One PCLR graft in the suture tape group failed. Posterior drawer examination revealed grade 1+ laxity in 4 of 19 (21%) of the suture tape cohort versus 6 of 31 (19%) of the control cohort (P > .999). Bilateral kneeling radiographs showed similar side-to-side differences in laxity between the groups (suture tape vs control: mean, 1.9 ± 0.4 vs 2.6 ± 0.6 mm; P = .361). There were no statistically significant differences between the groups in postoperative IKDC (suture tape vs control: 79.3 vs 79.6; P = .779), Lysholm (87.5 vs 84.3; P = .828), or Tegner activity (5.6 vs 5.7; P = .562) scores.

Conclusion

All-inside single-bundle PCLR with and without independent suture tape reinforcement demonstrated low rates of graft failure, complications, and reoperations, with satisfactory PROs at a minimum 2-year follow-up. Radiographic posterior tibial translation was comparable between the 2 groups.

Single versus double bundle in posterior cruciate ligament (PCL) reconstruction: a meta-analysis

Posterior cruciate ligament (PCL) reconstruction can be performed using single bundle (SB) and double bundle (DB) techniques. The present study investigated whether DB PCL reconstruction is superior to SB reconstruction in terms of patient reported outcome measures (PROMs) and joint stability. In December 2021 Embase, Google Scholar, Pubmed, Scopus databases were accessed. All clinical trials comparing SB versus DB reconstruction to address PCL insufficiency in skeletally mature patients were considered. Data from 483 procedures were retrieved. The mean follow-up was 31.0 (28.0 to 107.6) months, and the mean timespan between injury and surgery was 11.3 (6 to 37) months. The mean age of the patients was 29.3 ± 3.8 years. 85 of 483 patients (18%) were women. At a mean of 31.0 months post reconstruction, ROM (P = 0.03) was slightly greater in the SB group, while the Tegner score (P = 0.03) and the Telos stress (P = 0.04) were more favorable in the DB cohort. Similarity was found in instrumental laxity (P = 0.4) and Lysholm score (P = 0.3). The current evidence does not support the use of DB techniques for PCL reconstruction. Both methods could restore knee stability and motion with satisfactory short term patient reported outcome measures. Further high quality clinical trials are required to validate these results on a larger scale.

Four-Tunnel Double-Bundle Anatomical Posterior Cruciate Ligament Reconstruction Without Remnant Preservation

Double-bundle posterior cruciate ligament (PCL) reconstruction has long been attempted to obtain better clinical results than single-bundle PCL reconstruction. In most previous reports regarding double-bundle PCL reconstruction, one tibial tunnel and various kinds of grafts were used. We introduce a two-tibial tunnel, double-bundle PCL reconstruction technique with ultra-strong grafts. The critical points of this technique are proper creation of the tibial tunnels and the protection of the posterior neurovascular structures. Our clinical experience indicates this technique can lead to satisfactory stable outcomes. We believe that this technique will provide a reasonable choice for PCL reconstruction without remnant preservation.

Controversies in acute multiligamentary knee injuries (MLKI)

Multiligament injuries of the knee (MLKI), remain an infrequent pathology especially in developed countries compared to mono-ligament lesions. In Colombia, MLKI is frequent due to the high accident rate on motorcycles. In the city of Bogota alone, about 160 motorcycle accidents have been estimated daily, being one of the cities that proportionately use this means of transport less compared to small cities. The term MLKI, include all ruptures of two or more major ligaments and therefore it has a broad spectrum of clinical presentation which creates a great challenge for the orthopedists and the surgeons envolved in this topic. The literature is rich in studies level IV but very poor in level I and level II, which generates controversies and little consensus in the diagnosis and treatment of this pathology. However there has been a gradual and better understanding of all factors involved in the treatment of MLKI that has improved the functional results of these knees in our patients, in fact we currently are more precise to achieve accurate diagnosis, evolved from not surgical approach to operate most, applying new anatomical and biomechanical concepts, with specialized and skill surgical techniques with more stable and biocompatible fixation implants, which allow in most cases to initiate an early integral rehabilitation program. Nevertheless due to the complexity and severity of the lesions, in some patients the functional results are poor. The goal of this revision is to identify the most frequent controversies in the diagnosis and treatment of MLKI, defining which of them are agreed according to what is reported in the literature and share some concepts based from the experience of more than 25 years of the senior author (MM) in the management of these injuries. LEVEL OF EVIDENCE: V - Expert Opinion.

[Damage of the knee posterior cruciate ligament: biomechanics, basic diagnostics, treatment and secondary osteoarthritis prevention directions]

The analysis of literature data was performed on the pathogenesis, diagnosis and treatment of injuries of the posterior cruciate ligament (PCL) of the knee joint. PCL is the largest intra-articular ligament of the knee joint, can withstand the maximum loads compared with other ligaments. It was noted that, in general, in cases of damage to the PCL, it is necessary to use a set of diagnostic methods, and the basic principles for the choice of optimal treatment plan for this patient. It considered the results of the conservative treatment of PCL partial ruptures, and it is indicated that this approach increases the risk of degenerative anatomical structures and functional disorders of the joint. It was noted that it is advisable to conduct surgical treatment to restore the stability of the knee joint and normalize function, while a number of methods for the reconstruction of PCL have been proposed to date. The usage of chondroprotectors for prevention of the secondary osteoarthrosis of the knee joint affected by posterior cruciate ligament rupture was analyzed in the literature data.

Clinical Outcome of Arthroscopic Posterior Cruciate Ligament Reconstruction with Adjustable-Loop Femoral Cortical Suspension Devices

BACKGROUND

Incidence of isolated posterior cruciate ligament (PCL) injury is lower than PCL rupture is associated with other knee injuries. Adjustable loop femoral cortical suspension device is commonly used for femoral graft fixation during PCL reconstruction.

AIM

This study purpose is to describe the functional outcome of PCL reconstruction using an adjustable loop femoral cortical suspension device.

METHODS

This study used prospective design with consecutive sampling. All patients underwent PCL reconstruction with adjustable loop femoral cortical suspension devices using peroneus longus tendon autograft. Patients were evaluated at 6 months after surgery using posterior drawer test and functional outcome scoring system (Lysholm knee score, Cincinnati Score and International Knee Documentation Committee (IKDC) score).

RESULTS

20 patients were enrolled in this study with a mean age of 27.65 ± 9.78. Lysholm knee means the score was improved from 59.80 ± 18.73 pre-operative and 80.55 ± 11.72 post-operative (p < 0.05). Cincinnati mean score was improved from 52.01 ± 20.29 pre-operative to 72.95 ± 15.26 post-operative (p < 0.05). IKDC mean score was improved from 48.36 ± 13.18 at pre-operative to 72.5 ± 13.13 post-operative (p < 0.05).

CONCLUSION

PCL reconstruction using adjustable loop femoral cortical suspension device using peroneus longus tendon autograft showed good clinical outcome and knee functional outcome (Lysholm, Cincinnati, and IKDC score) at 6 months follow-up.

The use of allograft tissue in posterior cruciate, collateral and multi-ligament knee reconstruction

PURPOSE

Currently both autograft and allograft tissues are available for reconstruction of posterior cruciate, collateral and multi-ligament knee injuries. Decision-making is based on a complex interplay between anatomical structures, functional bundles and varying biomechanical requirements. Despite theoretically better biological healing and reduced risk of disease transmission autografts are associated with donor site morbidity as well as being limited by size and quantity. The use of allografts eliminates donor-site morbidity but raises cost and issues of clinical effectiveness. The purpose of this paper is to review current concepts and evidence for the use of allografts in primary posterior cruciate, collateral and multi-ligament reconstructions.

METHODS

A narrative review of the relevant literature was conducted for PCL, collateral ligament and multi-ligament knee reconstruction. Studies were identified using a targeted and systematic search with focus on recent comparative studies and all clinical systematic reviews and meta-analyses. The rationale and principles of management underpinning the role of allograft tissue were identified and the clinical and functional outcomes were analysed. Finally, the position of postoperative physiotherapy and rehabilitation was identified.

RESULTS

The review demonstrated paucity in high quality and up-to-date results addressing the issue especially on collaterals and multi-ligament reconstructions. There was no significant evidence of superiority of a graft type over another for PCL reconstruction. Contemporary principles in the management of posterolateral corner, MCL and multi-ligament injuries support the use of allograft tissue.

CONCLUSION

The present review demonstrates equivalent clinical results with the use of autografts or allografts. It remains, however, difficult to generate a conclusive evidence-based approach due to the paucity of high-level research. When confronted by the need for combined reconstructions with multiple grafts, preservation of synergistic muscles, and adapted postoperative rehabilitation; the current evidence does offer support for the use of allograft tissue.

LEVEL OF EVIDENCE

IV.