Isolated posterior cruciate ligament tears: an update of management

PCL injury following high energy trauma: associated injuries and postoperative complications "insights from a national registry study"

PURPOSE

The posterior cruciate ligament (PCL) is a vital knee stabilizer. While PCL injuries are rare, high-energy traumas can lead to total ruptures, with accompanying injuries requiring surgery. This study aims to investigate the demographics, concomitant injuries, and postoperative complications of patients who underwent PCL reconstruction due to high-energy trauma in a large patient sample.

METHODS

Patients who underwent PCL reconstruction from 2016 to 2022 were retrospectively evaluated using data from a nationwide personal health recording system. Patient demographics, injury mechanisms, associated fractures, soft tissue injuries, and postoperative complications were collected from patient notes, clinical visits, and surgical notes. Individuals with a PCL injury following high-energy trauma (car accident, falls from height, motorcycle accident) with a minimum follow-up of 1 year were included in the study.

RESULTS

The study included 416 patients with a mean age of 32.4 years. Isolated PCL injuries (n = 97, 23.3%) were observed less frequently than multiple-ligament injuries (n = 319, 76.7%). Most cases were treated with single-stage surgery (86.8%), while staged surgeries were performed in a minority of cases (13.2%). There was no relationship between trauma mechanisms and multiple-ligament involvement, accompanying injuries, or postoperative complications. Surgeries following car accidents were more likely to occur as staged surgeries (p = 0.014). Additionally, the complication rates for staged surgeries and younger patients (≤ 18 years) were significantly higher (p = 0.009).

CONCLUSION

High-energy trauma-induced PCL injuries are often associated with severe concurrent knee injuries with multiple ligament involvement. PCL reconstructions following car accidents are more likely to be staged. These findings highlight the importance of careful consideration in managing these cases to minimize complications, particularly in younger age groups.

LEVEL OF EVIDENCE

Level III.

Epidemiology of cruciate ligament reconstruction in the Australian Defence Force and predictors of outcome

BACKGROUND

The ability to predict the risk of poor outcome following knee cruciate ligament reconstruction in the Australian Defence Force (ADF) population would help direct individual rehabilitation programmes and workforce planning. This study describes the epidemiology of cruciate ligament reconstruction in the ADF and demonstrates the use of Bayesian networks (BN) to predict the likelihood of fitness for ongoing service under different scenarios.

METHODS

Members who had knee cruciate ligament reconstruction through ADF were identified from billing data and matched to electronic medical records to extract demographic and clinical data. Outcome measure was medical fitness for ADF service up to 24 months after reconstruction. BN models were used to compare outcomes between (1) age groups according to military service, and (2) sexes according to body mass index (BMI).

RESULTS

From November 2012 to June 2019, a total of 1199 individuals had knee cruciate ligament reconstruction (average 169 reconstructions/year). Following reconstruction and rehabilitation, 89 (7.4%) were medically unfit for service. Scenario analysis using a tree-augmented naïve BN model showed that, compared with Navy and Air Force, Army members had a higher probability of being unfit in those aged <35 years and a lower probability in those aged ≥35 years. In both sexes, those with obese BMI had the greatest probability of being unfit.

CONCLUSION

While most ADF members were fit for ongoing military service following cruciate ligament reconstruction, service type, age, sex and BMI influenced outcome. BNs provided an interactive and intuitive method to demonstrate the impact of different variables on the outcome.

Functional and MRI results after a 7.5 year follow-up of 35 single-stage ACL and PCL reconstructions using gracilis and semitendinosus tendon grafts and LARS artificial ligaments

PURPOSE

The aim of this study was to evaluate the long-term functional and MRI results of 35 patients who underwent bicruciate ligament reconstruction combining an ACL autograft using the gracilis and semitendinosus tendons and double-bundle PCL reconstruction using the LARS artificial ligament.

METHODS

The outcomes were measured using the Lysholm score, the Tegner activity level scale and the International Knee Documentation Committee form (IKDC 2000). KT-1000 was used to assess the clinical anterior knee laxity. Radiographs and Magnetic Resonance Imaging (MRI) was used to evaluate osteoarthritis, the continuity and integrity of ACL autograft and LARS.

RESULTS

This retrospective study examined 35 patients who underwent single-stage bicruciate ligament reconstruction between May 2005 and January 2017 with a follow-up period ranging from 3 to 15 years (a mean of 7.5 years). The mean Lysholm score was 74, mean IKDC 2000 was 71. There was a statistically significant difference with a higher Lysholm score (78.9) in early versus delayed surgical intervention (p = 0.023). Using the Kellgren Lawrence osteoarthritis classification system, radiographic findings showed stage II or III in 83% of the sample population. The MRI results revealed a rupture rate of 22% of the anterior autografted ligament and 28% of the posterior LARS artificial ligament. However, there were no long-term artificial ligament-induced complications. There was no correlation between artificial ligament rupture and poor functional results (Lysholm < 65).

CONCLUSION

The results of this study with a mean follow-up of 7.5 years show satisfactory functional scores considering the initial trauma. It seems reasonable to propose early surgical treatment with double reconstruction of the cruciate ligaments within the first 21 days of the trauma. Post-traumatic osteoarthritis is inevitable in multi-ligament knee injuries despite anatomical reconstruction. The use of a LARS artificial ligament appears to be a valid alternative for PCL reconstruction in the context of multi-ligament injury and in the absence of sufficient autologous transplants.

Innovative knee surgery: arthroscopic double bundle U-DOS reverse Technique for PCL tears

The Double Bundle U-DOS Reverse Technique for posterior cruciate ligament (PCL) tears is a novel arthroscopic technique that combines two well-known procedures: the mono-tunnel approach and the medial-portal approach, provides better posterior stability, improved functional outcomes, and a reduced risk of posterior tibial subluxation. This technique allows for the simultaneous treatment of anterolateral and posteromedial bundles and has been successfully performed on 16 patients, with follow-up showing sufficient support and resistance to posterior tibial subluxation or excessive displacement, resulting in a stable knee joint.

Tissue Augmentation Techniques in the Management of Ligamentous Knee Injuries

Despite early reports of high failure rates in knee ligament repair techniques resulting in favor of reconstruction, newer advances in surgical technology have shifted the attention back to repair with the addition of various tissue augmentation techniques. Ligament repair preserves proprioceptors in the native ligament and avoids autograft tendon harvest, minimizing the complications associated with donor site ruptures in reconstruction techniques. Tissue augmentation has been successfully used in knee ligamentous and tendon repair procedures, as well as in some upper extremity procedures. This study provides a clinical update on the surgical techniques, biomechanics, and outcomes with the application of various tissue augmentation techniques in the ligaments surrounding the knee joint.

Outcome Analysis of Posterior Cruciate Ligament Injuries: A Narrative Review

The primary posterior stabilizer of the knee is the posterior cruciate ligament (PCL), the largest intra-articular ligament in the human knee. One of the four primary ligaments of the knee joint, the PCL, serves to support the tibia on the femur. An extreme force applied anteriorly to the proximal tibia of the flexed knee results in trauma to the PCL. Dashboard injuries, which occur when the knee is driven into the dashboard after a collision with a motor vehicle, are frequent causes. Grade 1 and 2 acute injuries are often addressed conservatively due to the PCL's natural capacity for mending. If a grade 3 injury occurs, a cautious trial can be conducted on elderly or low-demand patients. When standard treatment for isolated grade 3 injuries has failed, surgery is advised. Single-bundle or double-bundle techniques using either transtibial tunnel or tibial inlay techniques are among the reconstruction approaches. Restoring the natural kinematics of the knee and forestalling persistent posterior and mixed rotatory knee laxity are the ultimate goals of treating PCL injuries through a personalized strategy. These injuries may become more common in the future as more people participate in sports. As a result of ongoing instability, discomfort, diminished function, and the emergence of inflammatory and degenerative disorders of joints, PCL rips are becoming more well-acknowledged as a cause of morbidity and decreased function.

Outcome of Arthroscopic All-Inside Posterior Cruciate Ligament Reconstruction Using the Posterior Trans-Septal Approach

Introduction

Posterior Cruciate Ligament (PCL) reconstruction is a complex surgical procedure and often challenging. The newer posterior trans-septal portal technique is thought to make tibial tunnel preparation easier with better visualization of the tibial attachment site. It is also thought to lower the risk of neurovascular injuries. The aim of this study was to evaluate the functional and clinical outcomes of patients who underwent arthroscopic all-inside PCL reconstruction using the posterior trans-septal portal at our institute.

Methods

This was a retrospective study with prospectively collected data between 2016 and 2020. Data collected were age, gender, types of graft used, range of movement, posterior drawer test grade, KOOS score, Lysholm knee scoring scale, and post-operative complications. All patients underwent pre- and post-operative PCL rehabilitation.

Results

A total of 36 patients (26 males and 10 females) were identified from our database. The mean age was 35.2 years. Mean time from injury to surgery was 20 months. Mean follow-up was 41.2 months (range, 13-72 months). Twenty cases involved multi-ligament injuries and another 16 patients had isolated PCL injury. Post-operative mean posterior drawer test grade improved from 2.7 to 0.7 (p < 0.001). Knee range of movement was 116.3 degrees pre-operatively and 115.6 degrees postoperatively (p = 0.814). Lysholm knee scoring scale improved from 50.9 to 91.0 (p < 0.001). KOOS score improved from 65.1 to 77.2 (p = 0.196). One patient required manipulation under anesthesia for stiffness. No patients needed any additional surgical procedures. All PCLs were clinically intact at the final follow-up.

Conclusion

Greater visualization of the PCL tibial attachment minimizes the 'killer turn' giving a huge advantage to this technique. Arthroscopic all-inside PCL reconstruction using the posterior trans-septal portal technique is a safe, reliable and reproducible procedure. From our study, it shows that post-operative clinical and functional outcomes improved significantly.

Posterior cruciate ligament repair seems safe with low failure rates but more high level evidence is needed: a systematic review

PURPOSE

To discuss recent literature on posterior cruciate ligament (PCL) repair and report on the clinical and radiological outcomes.

METHODS

A systematic review was conducted according to the PRISMA guidelines. In August 2022, three databases (PubMed, Scopus, and Cochrane Library) were searched for studies on PCL repair by two independent reviewers. Articles published between January 2000 and August 2022 focussing on the clinical and/or radiological outcomes, following PCL repair, were included. Patient demographic data, clinical evaluations, patient‑reported outcome measures, post-operative complications and radiological outcomes were extracted.

RESULTS

Nine studies met the inclusion criteria, covering 226 patients with a mean age ranging from 22.4 to 38.8 years and mean follow-up periods ranging from 14 to 78.6 months. Seven studies (77.8%) were level IV and two studies (22.2%) were level III. Arthroscopic PCL repair was performed in four studies (44.4%) while the remaining five studies (55.6%) described open PCL repair. In four studies (44.4%) additional suture augmentation was applied. Arthrofibrosis affected a combined total of 24 patients (11.7%; range 0-21.0%) making it the most common complication and the overall failure rate was 5.6%, ranging from 0 to 15.8%. Two studies (22.2%) performed post-operative MRI and confirmed PCL healing.

CONCLUSION

This systematic review indicates that PCL repair can be a safe procedure with an overall failure rate of 5.6%, ranging from 0% to 15.8%. However, more high quality research is necessary before widespread clinical implementation is warranted.

LEVEL OF EVIDENCE

IV.

Allografts as alternative to autografts in primary posterior cruciate ligament reconstruction: a systematic review and meta-analysis

PURPOSE

Following posterior cruciate ligament (PCL) rupture, autografts and allografts are routinely used for its reconstruction. This study investigated the efficacy and safety of allografts for primary PCL reconstruction, comparing them to autografts in terms of patient-reported outcome measures (PROMs), functional tests, and complications.

METHODS

This study followed the PRISMA guidelines. PubMed, Web of Science, Google Scholar, Embase, and Scopus were accessed in October 2022. All the clinical studies investigating the outcomes of primary PCL reconstruction using allografts, or comparing the outcomes of allografts versus autografts, were accessed. The outcomes of interests were: instrumental laxity, range of motion (ROM), Telos stress radiography, drawer test, International Knee Documentation Committee (IKDC), Tegner Activity Scale, and the Lysholm Knee Scoring Scale. Data on complications were also recorded.

RESULTS

A total of 445 patients were included. The mean follow-up was 45.2 ± 23.8 months. The mean age of the patients was 30.6 ± 2.2 years. The time span between the injury and surgical intervention was 12.9 ± 10 months. Overall, 28% (125 of 445 patients) were women. Good baseline comparability was found between the two cohorts. No difference was found in terms of Lysholm Score, ROM, Tegner Scale, IKDC, arthrometer laxity, drawer test, and Telos stress radiography. No difference was found in the rates of anterior knee pain and revision.

CONCLUSION

Allografts can be considered a suitable alternative to autografts for PCL reconstruction.

LEVEL OF EVIDENCE

III.

Return to Play after Posterior Cruciate Ligament Injuries

PURPOSE OF REVIEW

Posterior cruciate ligament injuries can be treated conservatively with a structured rehabilitation program or with surgical reconstruction. Treatment algorithms are based on a variety of factors including the patient's presentation, physical exam, and desired level of activity. The goal is to return the patient to their athletic pursuits with a stable and pain-free knee. Return to play and activities should be individualized based on the patient's injury and progression through rehabilitation. This article provides a review of the current treatments for posterior cruciate ligament injuries and the respective rehabilitation protocols, outcomes after each treatment option, and specific return to play criteria.

RECENT FINDINGS

Current research shows excellent outcomes and return to play with conservative treatment of isolated posterior cruciate ligament injuries. Return to play algorithms stress the importance of quadriceps strengthening throughout the recovery process and emphasize inclusion of plyometrics and sport-specific training. Rehabilitation plays a critical role in the outcome after posterior cruciate ligament injury and the ability to return to athletics. The primary focus of post-injury or post-operative rehabilitation is to restore function, as it relates to range of motion, strength, and proprioception, while mitigating swelling and pain. The patients' desired sport and level of play dictate return to play timelines. The literature supports the use of non-operative management of isolated PCL injuries in athletes and non-athletes with excellent functional and patient-reported 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.

Ligament Advanced Reinforcement System (LARS) synthetic graft for PCL reconstruction: systematic review and meta-analysis

INTRODUCTION

Several strategies are available for posterior cruciate ligament (PCL) reconstruction.

SOURCE OF DATA

Recently published literature in PubMed, Google Scholar and Embase databases.

AREAS OF AGREEMENT

The Ligament Advanced Reinforcement System (LARS) is a scaffold type artificial ligament, which has been widely used for ligament reconstruction of the knee.

AREAS OF CONTROVERSY

Current evidence on the reliability and feasibility of LARS for primary isolated PCL reconstruction is limited.

GROWING POINTS

The primary outcome of interest of the present work was to investigate the outcomes of PCL reconstruction using the LARS. The secondary outcome of interest was to compare the LARS versus four-strand hamstring tendon (4SHT) autograft for PCL reconstruction.

AREAS TIMELY FOR DEVELOPING RESEARCH

LARS for primary isolated PCL reconstruction seems to be effective and safe, with results comparable to the 4SHT autograft.

Clinical Accuracy of the Lateral-Anterior Drawer Test for Diagnosing Posterior Cruciate Ligament Rupture

BACKGROUND

Commonly used clinical posterior cruciate ligament (PCL) tests present with diagnostic weaknesses requiring alternative clinical tests. The Lateral-Anterior Drawer test (LAD-test) is a suggested alternative that previously demonstrated concurrent validity in situ. Further in vivo LAD-test clinical accuracy examination is required prior to any recommendation for clinical adoption. Thus, this case-control study aims to (1) investigate the LAD-test's in vivo interrater and intra-rater reliability; (2) establish LAD-test concurrent validity against MRI as the reference standard; and (3) examine the correspondence between examiners' professional working experience and LAD-test diagnostic accuracy.

METHODS

Three examiners with different professional experience levels, blindfolded during testing, and blinded from subjects' identity, medical history, and reference test outcome performed all LAD-testing twice per subject. Reliability analyses included percent agreement, Fleiss' kappa and Cohen's kappa coefficients with 95% Confidence Intervals (CIs) and prevalence-adjusted bias-adjusted kappa (PABAK) calculations. Validation parameters included sensitivity, specificity, likelihood ratios (LR + ; LR-), and predictive values (PPV; NPV) each accompanied by 95%CIs; each tester's percent agreement with the MRI; and their Youden Index.

RESULTS

The study sample was comprised of 31 subjects of which 14 had a history of unilateral full-thickness PCL-rupture. Their 14 contralateral knees and both knees of 17 healthy subjects served as controls. In vivo LAD-test performance did not produce any negative ramifications for the tested subjects. Interrater reliability was moderate (test-1: Fleiss'κ = 0.41; 95% CI 0.40;0.41; test-2:Fleiss'κ = 0.51; 95% CI 0.50;0.51). Pairwise examiner's LAD-test outcome agreement ranged from 74 to 89%. Pairwise interrater reliability was fair-to-substantial (κ = 0.27 to κ = 0.65) with moderate-to-substantial PABAK (0.48-0.77). Intra-rater reliability was substantial-to-almost perfect (PABAK 0.65-0.97). Sensitivity and specificity ranged from 57 to 86% and 83 to 98%, respectively. The advanced and novice clinicians' Youden Indexes were acceptable. The same examiners' positive likelihood ratios revealed important and relative important effects, respectively. Positive predictive values were considerable for the advanced and novice clinicians, while negative predictive values were high for all examiners.

CONCLUSION

Overall, the study results suggested LAD-test practicability. In vivo LAD-test performance did not produce any negative ramifications for the tested subjects. In subjects presenting with a chronic PCL-deficiency (i.e., > 3 months since initial injury), the LAD-test's clinical accuracy was comparable-to-superior to other commonly used clinical PCL-tests. Future studies to establish the LAD-test's usefulness in isolation as well as in combination with other clinical tests for acute PCL-rupture diagnostics are warranted.

TRIAL REGISTRATION NUMBER

DRKS00013268 (09. November 2017).

Standardized Rehabilitation or Individual Approach?—A Retrospective Analysis of Early Rehabilitation Protocols after Isolated Posterior Cruciate Ligament Reconstruction

(1) Background: Isolated posterior cruciate ligament (PCL) tears represent a severe type of injury. In hospitals, PCL reconstruction (PCL-R) is less frequently performed than other types of knee surgery. It is unclear whether there is consensus among surgeons on how to perform rehabilitation after PCL-R or if there are different, more individual approaches in daily routines. (2) Methods: Rehabilitation protocols and their main criteria (the progression of weight bearing and range of motion, the use of knee braces, rehabilitation training, and sports-specific training) were retrospectively analyzed after PCL-R. (3) Results: Only 33 of 120 (27.5%) analyzed institutes use rehabilitation protocols after PCL-R. The applied protocols showed vast differences between the individual rehabilitation criteria, especially with regard to the progression of weight bearing and the range of motion. The only standardized recommendations were the obligatory use of knee braces and the general restriction of weight bearing and range of motion immediately post-surgery. Therefore, because of the lack of a consensus about a standardized rehabilitation protocol after PCL-R, no recommendation can be made on one particular protocol. (4) Conclusion: There is no acknowledged standardized rehabilitation protocol after PCL-R. In clinical practice, recommendations are influenced by, i.a., surgeons’ opinions and experience. The lack of scientific evidence on a particular standardized rehabilitation protocol after PCL-R suggests that rehabilitation protocols need to be tailored to the individual patient.

Open reduction and internal fixation of the tibial avulsion fracture of the posterior cruciate ligament: which is better, a hollow lag screw combined with a gasket or a homemade hook plate?

OBJECTIVE

To compare the clinical results of homemade hook plates and hollow lag screws combined with spacers in the treatment of posterior cruciate tibial ligament avulsion fractures.

MATERIALS AND METHODS

This was a retrospective clinical cohort study that included 64 patients with PCL tibial avulsion fractures. Thirty-two of them were fixed with a homemade hook plate (hook plate group), and 32 were fixed with a hollow lag screen combined with a gasket (hollow lag screen group). By reviewing the medical record data and follow-up results, the operation time, postoperative drainage, fracture healing time, surgical complications, knee mobility, recovery of joint function, and whether postoperative gastrocnemius muscle strength changed in the two groups were compared.

RESULTS

All patients had successful wound and fracture healing. No adverse events, such as bone nonunion, infection, wound haematoma, or joint stiffness, occurred in either group. There were no patients with decreased gastrocnemius muscle strength in either group. Internal fixation failure occurred in 2 cases in the hollow lag screen group but not in the hook plate group. There were no significant differences between the two groups in terms of operative time, postoperative drainage, fracture healing time, knee mobility at the last follow-up, or Lysholm score.

CONCLUSION

It is safe and effective to use a homemade hook plate to fix PCL tibial avulsion fractures through an inverted L-shaped posterior medial approach. A homemade hook plate may have potential advantages over a hollow lag screen combined with gasket fixation.

Outcomes of tibial avulsion fracture of the posterior cruciate ligament treated with a homemade hook plate

OBJECTIVE

To compare the clinical effects of an inverted L-shaped postero-medial approach with a homemade hook plate and arthroscopic fixation with Endobutton for tibial avulsion fractures of the posterior cruciate ligament.

METHODS

The clinical data of 36 patients with PCL tibial avulsion fractures from January 2012 to December 2019 were analyzed retrospectively. The fractures were classified into Meyers-McKeever types II and III. Among them, 20 cases were treated with a homemade hook plate through an inverted L-shaped postero-medial approach (incision group), and 16 cases were treated with Endobutton under arthroscopy (arthroscopic group). The operative time, fracture union time, operative complications and range of motion of the knee joint were compared between the two groups. The stability of the knee joint was tested by the posterior drawer test, the functional recovery of the knee joint was evaluated by the Lysholm score, and the gastrocnemius muscle strength of the incision group was tested by performing heel raises with a single leg stance.

RESULTS

There were no adverse events, such as fracture nonunion, infection, deep-vein thrombosis, abnormal hematoma or joint stiffness, in either group. The operative time was shorter in the incision group, and the difference was statistically significant (P < 0.05). There was no significant difference in fracture union time between the two groups (P > 0.05). At the last follow-up, there was no significant difference in range of motion or the Lysholm score between the two groups. There was no decrease in gastrocnemius muscle strength in the incision group.

CONCLUSIONS

The fixation of PCL tibial avulsion fractures with a homemade hook plate through an inverted L-shaped postero-medial approach is safe and effective. It showed almost the same satisfactory outcomes as arthroscopic Endobutton fixation.

Nanoscopic-Assisted Anterior Cruciate Ligament-Posterior Cruciate Ligament Reconstruction

Knee arthroscopy has allowed us to continue performing surgeries that are minimally invasive and allow patients to have a quick recovery. Multiligamentous knee reconstruction with regards to the anterior cruciate ligament and posterior cruciate ligament can be done in a minimally invasive matter. Visualization is an issue during this surgery, especially looking in the posterior compartment of the knee. The NanoScope (Arthrex, Naples, FL) continues to provide increased possibilities for orthopaedic surgeons. Our technique provides a less-invasive way to observe the posterior compartment to assist the drilling of the tibial tunnel during the posterior cruciate ligament reconstruction. This technique provides distinct advantages over other treatments.

Anatomy and Biomechanics of the Posterior Cruciate Ligament

Posterior cruciate ligament (PCL) injuries are often encountered in the setting of other knee pathology and sometimes in isolation. A thorough understanding of the native PCL anatomy is crucial in the successful treatment of these injuries. The PCL consists of two independent bundles that function in a codominant relationship to perform the primary role of resisting posterior tibial translation relative to the femur. A secondary role of the PCL is to provide rotatory stability. The anterolateral (AL) bundle has a more vertical orientation when compared with the posteromedial (PM) bundle. The AL bundle has a more anterior origin than the PM bundle on the lateral wall of the medial femoral condyle. The tibial insertion of AL bundle on the PCL facet is medial and anterior to the PM bundle. The AL and PM bundles are 12-mm apart at the center of the femoral origins, while the tibial insertions are more tightly grouped. The different spatial orientation of the two bundles and large distance between the femoral centers is responsible for the codominance of the PCL bundles. The AL bundle is the dominant restraint to posterior tibial translation throughout midrange flexion, while the PM bundle is the primary restraint in extension and deep flexion. Biomechanical testing has shown independent reconstruction of the two bundles that better reproduces native knee biomechanics, while significant differences in clinical outcomes remain to be seen. Stress X-rays may play an important role in clinical decision-making process for operative versus nonoperative management of isolated PCL injuries. Strong understanding of PCL anatomy and biomechanics can aid surgical management.

Arthroscopic Primary Repair of the Posterior Cruciate Ligament

The posterior cruciate ligament (PCL) is one of the four major stabilizers of the knee joint and functions as the primary restraint to posterior tibial translation. PCL tears rarely occur in isolation and most commonly presents in the setting of multiligamentous knee injuries. Several treatment strategies for these injuries have been proposed over the last decades, including ligament reconstruction and primary repair. Arthroscopic primary PCL repair has the potential to preserve native tissue using a more minimally invasive approach, thereby avoiding donor-site morbidity and allowing early mobilization. While arthroscopic PCL repair is certainly not an effective surgical approach for all patients, this procedure may be a reasonable and less morbid alternative to PCL reconstruction in selected patients treated for proximal or distal avulsion tears, with low failure rates, good knee stability, and good to excellent subjective outcomes. The surgical indications, surgical techniques, postoperative management, and outcomes for arthroscopic primary repair of proximal and distal PCL tears will be discussed in this review.

Posterior Cruciate Ligament Reconstruction With Independent Suture Tape Reinforcement: An In Vitro Biomechanical Full Construct Study

Background:

Posterior cruciate ligament (PCL) reconstruction is commonly performed to restore joint stability and prevent posterior tibial translation at higher flexion angles. However, persistent knee laxity after reconstruction is often reported.

Purpose:

To biomechanically evaluate the effect of independent suture tape (ST) reinforcement on different PCL reconstruction techniques.

Study Design:

Controlled laboratory study.

Methods:

PCL reconstruction using porcine bones and quadrupled bovine tendons was performed using 2 techniques: (1) an all-inside method using suspensory adjustable loop devices (ALDs) in the tibia and femur and (2) a method using an interference screw on the tibial and an ALD on the femoral site. Both were tested with and without an additional ST for 4 groups (n = 8 per group). Each construct underwent biomechanical testing involving 3000 loading cycles in 3 stages. After position-controlled cycles simulating full range of motion, force-controlled loading from 10 to 250 N and then from 10 to 500 N were performed before pull-to-failure testing. Elongation, stiffness, and ultimate strength were evaluated.

Results:

The highest ultimate load (1505 ± 87 N), a small total elongation (2.60 ± 0.97 mm), and stiffness closest to the native human ligament (156.3 ± 16.1 compared with 198.9 ± 33.5 N/mm; P = .192) was seen in the all-inside technique using ST. Intragroup comparison revealed that reinforcement with ST produced a smaller total elongation for the screw fixation (Screw-ALD, 6.06 ± 3.60 vs Screw-ALD ST, 2.50 ± 1.28 mm; P = .018) and all-inside techniques (ALD-ALD, 4.77 ± 1.43 vs ALD-ALD ST, 2.60 ± 0.97 mm; P = .077), albeit the latter was not significantly different. Elongation for constructs without ST increased more rapidly at higher loads compared with elongation for ST constructs. The ultimate strength was significantly increased only for constructs using the all-inside technique using ST (ALD-ALD, 1167 ± 125 vs ALD-ALD ST, 1505 ± 87 N; P = .010).

Conclusion:

Adding an independent ST to PCL reconstruction led to improvement in the studied metrics by reducing the total elongation and increasing the ultimate strength, independent of the technique used.

Clinical Relevance:

PCL reconstruction using additional ST reinforcement was biomechanically favorable in this study. ST reinforcement in the clinical setting could decrease knee laxity after PCL reconstruction, providing better joint stability and improved functional outcomes.

Quadriceps tendon autograft is an effective alternative graft for posterior cruciate ligament reconstruction in isolated or multiligament injuries: a systematic review

IMPORTANCE

High-grade posterior cruciate ligament (PCL) tears can be a significant cause of patient morbidity and knee instability. The graft of choice for operative repair remains controversial, although recently there has been increased interest in quadriceps tendon (QT) as an autologous graft option.

OBJECTIVE

The purpose of this study was to perform a systematic review to assess reported clinical outcomes of PCL reconstructions using QT autografts.

EVIDENCE REVIEW

A comprehensive review of clinical studies was performed evaluating PCL reconstruction with QT autograft including a systematic search of PubMed, Scopus, Cochrane and Google Scholar databases, and reference lists of relevant papers. Clinical results, stability results, functional outcomes, range-of-motion outcomes, complications and morbidity, and the conclusions of each study were evaluated.

FINDINGS

Seven studies were included in the review of clinical results, including 145 subjects undergoing PCL reconstructions with QT autograft. All studies evaluated quadriceps tendon bone (QT-B) grafts. Among these seven studies, two included isolated PCL reconstruction while five included multiligamentous knee injury reconstruction. These studies suggest that QT-B autograft offers a viable graft option for primary PCL reconstruction with generally favourable patient-reported outcomes, knee stability and range of motion reported along with relatively low complication rates.

CONCLUSIONS AND RELEVANCE

Use of the QT-B autograft may be a reasonable graft option for PCL reconstruction. However, high-quality prospective studies are required to evaluate the long-term safety, efficacy and functional outcomes.

LEVEL OF EVIDENCE

Level IV (Systematic review of Level IV studies).

Promising clinical and magnetic resonance imaging results after internal bracing of acute posterior cruciate ligament lesions in multiple injured knees

PURPOSE

The purpose of this study was to evaluate the clinical and radiological outcomes of acute posterior cruciate ligament (PCL) lesions in multiple injured knees that were surgically treated with internal bracing.

METHODS

Acute complete PCL lesions in multiple injured knees with subsequent internal-bracing treatment within 21 days between 2014 and 2016 were eligible for inclusion. At final follow-up, patients were assessed with Tegner, Lysholm, and IKDC scores. PCL stability and healing were verified with KT-2000, stress radiography and magnetic resonance imaging (MRI).

RESULTS

Fourteen patients [mean age 37.4 (± 17.8; SD) years] were evaluated after a mean follow-up of 19.9 (± 7.7; SD) months. Thirteen patients suffered complete lesions of the PCL with concomitant ligamentous injuries (Schenck I: six cases, Schenck III M: five cases, Schenck IV N: one case, Schenck V: one case). Median Tegner, mean Lysholm and mean IKDC scores at follow-up were 4 (2-7; interquartile range), 69.1 (± 16.6; SD) and 68.9 (± 18.1; SD) respectively. Posterior translation averaged 5.8 (± 2.2; SD) mm with the KT 2000 and stress radiography showed a mean posterior tibial translation of 5.5 (± 4.1; SD) mm in the side to side comparison. MRI showed adequate PCL healing.

CONCLUSIONS

Internal bracing as treatment for acute PCL ruptures in multiple injured knees showed adequate restoration of posterior tibial translation in a single-centre study including 14 cases.

LEVEL OF EVIDENCE

IV.

Changes in hamstring strength after anterior cruciate ligament reconstruction with hamstring autograft and posterior cruciate ligament reconstruction with tibialis allograft

Aim

The aim of this study was to evaluate the changes in hamstring strength both after anterior cruciate ligament reconstruction (ACLR) with hamstring autograft followed by early rehabilitation and posterior cruciate ligament reconstruction (PCLR) with tibialis allograft followed by delayed rehabilitation.

Methods

Isokinetic strengths of the quadriceps and hamstring muscles and endurances were compared between a group of 20 patients undergoing PCLR using a tibialis anterior allograft and a 1:2 matched control group of 40 patients undergoing ACLR using a hamstring autograft at 2 years after the operations. Clinical results were also compared using stability tests and the Lysholm and the International Knee Documentation Committee scores.

Results

At 2 years after the operations, the torque deficit of the hamstring muscle in the involved leg compared to the uninvolved leg at both 60°/s and 120°/s was greater in the PCLR group than in the ACLR group (60°/s, 21.8 ± 14.0% versus 1.9 ± 23.9%, P = 0.0171; 120°/s, 15.3 ± 13.7% versus −0.7 ± 17.4%, p = 0.012, respectively). The peak torque of the hamstring muscle at 120°/s was significantly lower in the involved leg than in the uninvolved leg only in the PCLR group (71.3 ± 31.9 N∙m versus 81.9 ± 27.8 N∙m, P = 0.005). There was no significant difference in the clinical results between the groups except for a side-to-side difference in the tibial translation on Telos stress radiographs.

Conclusion

The strength of the hamstring of the PCLR leg with allograft was significantly weaker than that of the unoperated leg after 2 years, whereas that of the ACLR leg with hamstring autograft maintained a similar level of strength compared to that of the uninvolved leg.

Level of evidence

Level III, case–control study.

Double-bundle posterior cruciate ligament reconstruction: No differences between two types of autografts in isolated or combined lesions

BACKGROUND

To demonstrate and compare results obtained with the transtibial double-bundle posterior cruciate ligament (PCL) reconstruction technique using two types of autografts in isolated and combined PCL lesions.

METHODS

Fifty-two patients with isolated or combined PCL injuries underwent double-bundle PCL reconstruction and were retrospectively evaluated. Among them, 34 were reconstructed using ipsilateral quadriceps and semitendinosus tendon grafts, and 18 were reconstructed using bilateral hamstring tendon grafts. The criteria for outcome evaluation were: objective International Knee Documentation Committee (IKDC) score, Lysholm score, posterior stability (posterior drawer test and KT-1000TM), and rate of complications, comparing the two types of grafts and comparing isolated PCL and combined lesions. The minimum follow-up was two years.

RESULTS

Significant improvements were found in all evaluation methods between the pre- and postoperative periods (all P < .05), with no observed differences between the graft type that was used (all P > .05). The whole sample had the following results: objective IKDC score, 96.2% classified as A/B; Lysholm score, 98.1% rated as good or excellent; and KT-1000, 98.1% with a side-to-side difference of up to five millimeters (65.4% with 0 to two millimeters). The complication rate was 9.6%, with no differences between the graft type that was used (P = .585). No significant difference was observed when comparing the results between isolated PCL injuries and combined injuries (all P > .05).

CONCLUSIONS

The proposed PCL reconstruction technique presented satisfactory results in both isolated and combined PCL lesions, and there were no differences between different types of autografts used.

LEVEL OF EVIDENCE

Level III.

Posterior cruciate ligament reconstruction implemented by the Ligament Advanced Reinforcement System over a minimum follow-up of 10 years

PURPOSE

This study evaluated the long-term clinical follow-up results of patients who underwent double-bundle posterior cruciate ligament (PCL) reconstruction using the Ligament Advanced Reinforcement System (LARS).

METHODS

Patients were assessed using clinical scores that included the Tegner activity level scale, the Lysholm score, and the International Knee Documentation Committee (IKDC) score. KT-1000 was adopted to assess stability. Radiographs and magnetic resonance imaging (MRI) were used to evaluate osteoarthritis and LARS condition.

RESULTS

This study examined 38 patients, of which follow-up procedures were completed for 33 patients, resulting in a follow-up rate of 86.8%. The average follow-up period was 11.9 ± 1.2 years (range: 10.3-14.2 years). The median scores of the clinical scales were as follows: Tegner activity score, 6 (range: five to seven); Lysholm score, 90 (range: 67-100); and IKDC score, 89.7 (range: 46-100). The median of the side-to-side difference (SSD) was four millimeters (range: 0-10 mm). In radiographs, the moderate OA rate was 6.9%. MRI results revealed that 26 patients exhibited ingrowth and 11 patients exhibited partial rupture of the LARS. With SSD ≤ 3 mm set as the standard for successful knee stabilization, the optimal cutoff point of LARS midsubstance thickness in the receiver operating characteristic (ROC) curve analysis was 14.3 mm.

CONCLUSIONS

Long-term follow-up of the studied patients demonstrated the durability of LARS. However, clinical outcomes showed no enhancement using LARS, so it is not recommended for routine use in PCL reconstruction.

LEVEL OF EVIDENCE

IV.

Bay11-7082 facilitates wound healing by antagonizing mechanical injury- and TNF-α-induced expression of MMPs in posterior cruciate ligament

Purposes: To investigate the ability of synoviocytes (SCs) in regulating MMPs expression in the posterior cruciate ligament fibroblasts (PCLfs) after TNF-α treatment, to test whether a specific inflammation inhibitor Bay11-7082 can antagonize the expression of MMPs in PCLfs after injury. Methods: The microenvironment of knee joint cavity after PCL injury was mimicked in an in vitro co-culture system. The effects of TNF-α treatment on the expression of MMPs in PCL fibroblasts (PCLfs) were studied. The expression of MMPs mRNA and protein was detected by qRT-PCR and western blot. For the in vivo study, the Bay11-7082 inhibitor was injected into the knee joint cavity after injury, and then were performed on histological analysis. Results: In the mono-culture conditions, 6% mechanical injury upregulated the expression of MMP-2, whereas downregulated MMP-1 and -3, additionally 12% mechanical injury were upregulated all. However, in co-culture conditions, 6% and 12% both significantly increased MMPs expressions. Stretch injury and TNF-α treatment significantly upregulated expression of MMPs mRNA and protein levels in mono-cultured PCLfs. This effect was more significant in PCLfs Plus SCs co-culture system, in which the cells were treated by combination of stretch injury and TNF-α. In addition, Bay11-7082, a specific inflammation inhibitor, could significantly decrease the expression of MMPs induced by stretch injury and/or TNF-α treatment. Less infiltrated inflammatory cells and more integrated tissues were detected in injury PCL 2 weeks after Bay11-7082 treatment, compared to injury group. Immunofluorescent staining showed very low expression levels of MMPs in PCL of Bay11-7082-treated group, compared to the injury groups. Conclusions: SCs sever as the supporting cells that aggravate the TNF-α-induced MMPs accumulation in PCLfs. Inhibition of the expression of MMPs by Bay11-7082 is a promising way to facilitate the self-healing of PCL.

Clinics in diagnostic imaging (196). Complete PCL tear

A 21-year-old man presented with left knee pain and instability that persisted three months after a road traffic accident. Physical examination revealed a positive posterior drawer test. Anterior drawer and pivot tests were negative. Magnetic resonance imaging of the knee demonstrated a complete tear of the posterior cruciate ligament (PCL). Recognition of the normal and injured appearances of the PCL is useful to aid the reader in the detection and characterisation of PCL injuries. Isolated acute PCL tears are usually managed conservatively. However, an active search for associated injuries is essential, as their presence may upstage the patients for surgical management.

Ultrasound anatomy of the normal stifle in the sheep

Though the ovine stifle is commonly used as a model in research, there is no description of its anatomy at ultrasonography (US). The objective of this study was to provide reference US images of the ovine stifle that are relevant in musculoskeletal research. Four pairs of hindlimbs were scanned, whilst four other pairs were frozen and cut in different planes to compare gross anatomy to US scans. In another pair, the synovial compartments of the stifle were injected and scanned. This study demonstrated that US could be used to assess the ovine stifle. Several structures of clinical interest could be identified with cranial, lateral and medial approaches, such as (a) the tendons of m. quadriceps femoris, m. gluteobiceps, m. popliteus, (b) the common tendon of m. peroneus tertius-extensor longus digitorum-extensor digiti III proprius, (c) the patellar ligament, (d) the medial and lateral collateral ligaments, (e) the cranial horn and middle segment of medial and lateral meniscus, and (f) the synovial recesses. However, the caudal approach was not successful to identify caudal anatomical structures of the joint, due to the muscular mass, that is the caudal aspects of the articular surfaces of the femoral and tibial condyles, the caudal horns of the menisci and the supracondylar synovial recesses. In addition, US remained challenging to assess the internal structures such as cruciate ligaments and articular surfaces. The feasibility of US needs to be tested in vivo.

Arthroscopic repair of the meniscus: Surgical management and clinical outcomes

From the biomechanical and biological points of view, an arthroscopic meniscal repair (AMR) should always be considered as an option. However, AMR has a higher reoperation rate compared with arthroscopic partial meniscectomy, so it should be carefully indicated.

Compared with meniscectomy, AMR outcomes are better and the incidence of osteoarthritis is lower when it is well indicated.

Factors influencing healing and satisfactory results must be carefully evaluated before indicating an AMR.

Tears in the peripheral third are more likely to heal than those in the inner thirds.

Vertical peripheral longitudinal tears are the best scenario in terms of success when facing an AMR.

‘Inside-out’ techniques were considered as the gold standard for large repairs on mid-body and posterior parts of the meniscus. However, recent studies do not demonstrate differences regarding failure rate, functional outcomes and complications, when compared with the ‘all-inside’ techniques.

Some biological therapies try to enhance meniscal repair success but their efficacy needs further research. These are: mechanical stimulation, supplemental bone marrow stimulation, platelet rich plasma, stem cell therapy, and scaffolds and membranes.

Meniscal root tear/avulsion dramatically compromises meniscal stability, accelerating cartilage degeneration. Several options for reattachment have been proposed, but no differences between them have been established. However, repair of these lesions is actually the reference of the treatment.

Meniscal ramp lesions consist of disruption of the peripheral attachment of the meniscus. In contrast, with meniscal root tears, the treatment of reference has not yet been well established.

Cite this article: EFORT Open Rev 2018;3:584-594. DOI: 10.1302/2058-5241.3.170059