Surgical management of PCL injuries: indications, techniques, and outcomes

All-inside posterior cruciate ligament reconstruction - A systematic review of current practice

Purpose

The All-Inside PCL Reconstruction is a surgical technique which overcomes some of the key challenges faced with traditional PCL Reconstruction, and is becoming more relevant as the rate of PCL reconstruction increases.The purpose of this study is to review the technical practices of the all-inside PCL reconstruction since it was first introduced, with respect to the various key components involved in the surgical technique, to provide more information to the surgeon of the various surgical options available in practice.

Materials and methods

A systematic review was performed by the authors in January 2023 as per Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines to identify all studies outlining the all-inside surgical technique in the past decade. The predetermined eligibility criteria were applied in the screening of the literature in Pubmed, Cochrane and Google Scholar databases.

Results

A total of 14 studies were included in the final review, 9 technical studies, 2 case series, 2 book chapters and 1 review. An allograft was the preferred choice in 9 of the 14 studies. The semitendinosus was preferred when an autograft was chosen. Quadruple folding of the graft was the preferred configuration in 11 studies with the graft diameters from 8 to 12 mm and length ranging from 60 to 150 mm. The femur socket length ranged from 15 to 35 mm and the tibia socket length ranged from 20 to 70 mm. All the studies reported the use of at least 3 portals and up to 6 portals was also reported. 13 studies reported the graft docking first into tibia socket followed by the femoral socket. 7 studies reported the graft entry via the AM portal and 6 studies used a lateral portal. 9 studies used augmentation such as suture anchors (6 studies) and suture tape (3 studies). The 30° and 70° arthroscopic lenses were used alternatingly in 8 studies and fluoroscopy was utilized in 10 studies.

Conclusion

The current literature review of all-inside PCL reconstruction consisted mainly technical studies and more clinical outcomes studies are needed to determine its efficacy. It observed a trend to use an allograft, at least 3 portals and docking the graft in the tibia socket first. There is no obvious preference of portal for graft entry.

Open Repair of Posterior Cruciate Ligament Tibial Bony Avulsion With Metal Anchor: A Case Report

Introduction: The posterior cruciate ligament (PCL) is the largest and strongest intra-articular ligament of the knee joint and the primary posterior stabilizer. PCL injuries are less frequent than other knee ligament injuries and are typically combined with meniscal and chondral injuries or in the context of multiligamentous injuries. It is critical to properly diagnose and treat these lesions in order to avoid the risk of PCL insufficiency, subsequent knee instability, and early osteoarthritis. Surgical management can vary, and the ideal fixation device is still debated. Suture anchors are an unusual mean of fixation of PCL tibial bony avulsion. We report on two patients treated with open anchor fixation for PCL tibial bony avulsion with a follow-up of 3 years. Case Presentation: A 15-year-old male and a 65-year-old male were treated with open anchor fixation for bony tibial avulsion of the PCL. Surgical treatment was performed at 5 weeks and 3 weeks after the trauma, respectively. Diagnosis was made with an X-ray followed by CT and MR scans. Repair was achieved by reinserting the PCL bony fragment to its posterior tibial eminence with suture anchors through an open posterior approach. Both patients recovered full knee stability and a pain-free full range of motion (ROM) within 4 months and returned to their previous activities with a high satisfaction. The patient has been followed up for 3 years, and no complications were observed. Conclusion: PCL bony avulsions are rare, and their optimal treatment remains a significant subject of debate, particularly in the skeletally immature patient. We believe that open repair with metal anchors could be a good choice to repair PCL bony tibial avulsion in patients without concomitant intra-articular lesions and immature growth plates or severe fragmentation.

Management of pediatric posterior cruciate ligament avulsion fractures: a systematic review

PURPOSE

Both open and arthroscopic surgical techniques have been used for PCL avulsion fractures. The goal of this study is to evaluate the effectiveness and safety of the different management strategies proposed for PCL avulsion fractures in children.

METHODS

A systematic literature review was performed utilizing Medline, Scopus, and EMBASE databases from 1977 to the present. PRISMA guidelines were followed. Data were selected and extracted by two independent reviewers. Inclusion criteria were clinical studies reporting injuries in pediatric patients with PCL avulsion injuries. Exclusion criteria were combined PCL and ACL injuries and ligamentous injuries requiring reconstruction. A subgroup analysis was performed between open reduction and arthroscopic surgeries.

FINDINGS/RESULTS

Twenty-six studies were included in this systematic review. Patient sex was reported in 39 patients with a higher number of males (32/39). The age range was 7-18 years old. In the open group, 30/31 patients had clinical improvement or returned to pre-injury activity level with two complications. Lysholm scores ranged from 66 to 99. In the arthroscopic group, 11/12 patients experienced clinical improvement or returned to normal activity levels with only one complication. Lysholm scores ranged from 90 to 100 with a mean of 95. In the non-operative group, 3/3 recovered with evidence of fracture healing, full or near full knee range of motion. One Lysholm score was reported 14 months after injury and was 100/100.

CONCLUSIONS

Open reduction and arthroscopic surgeries are effective and safe treatment options for pediatric PCL avulsion fractures-97% of open reduction and 92% of arthroscopic patients significantly improved symptoms. The complication rates for the open and arthroscopic groups were 11 and 9%, respectively. All three non-operative made full or near full recovery of pre-injury knee status.

LEVEL OF EVIDENCE IV

Systematic review of Level-II-IV studies. Prospero Registration No CRD42021290899.

Modified arthroscopic repair of a posterior cruciate ligament tibial avulsion fracture improves IKDC and Lysholm score compared to open reduction

PURPOSE

The purpose of this study was to analyse the difference between arthroscopic fixation and open reduction internal fixation (ORIF) of posterior cruciate ligament (PCL) tibial avulsion fractures.

METHODS

This retrospective study analysed patients with an acute PCL tibial avulsion fracture who underwent surgical treatment at our hospital and follow-up for at least 24 months. Variables based on sex, age, Meyers-McKeever type, surgical method, meniscus tear, external fixation, labour or sports, Lysholm knee score, IKDC score, and KT-1000 value were also recorded. Multifactor unconditional logistic regression and Student's t test with 1:1 propensity score matching (PSM) to remove confounding factors were used for analysis.

RESULTS

Sixty-five cases achieved knee function graded as "good" or better, and 9 cases not. Single-factor analysis indicated that Meyers-McKeever type (χ2 = 4.669, P = 0.031) and surgical approach (χ2 = 9.428, P = 0.002) are related to functional outcomes. Multifactorial logistic regression analysis further confirmed that Meyers-McKeever typing (OR = 10.763, P = 0.036, [95% CI 1.174-98.693]) and surgical approach (OR = 9.274, P = 0.008, [95% CI 1.794-47.934]) are independent risk factors affecting prognosis. In addition, PSM verified significant differences in the Lysholm score (t = 3.195, P = 0.006), IKDC score (t = 4.703, P = 0.000) and A-KT/H-KT (t = 2.859, P = 0.012). However, the affected-side KT-1000 value (A-KT, mm, t = 1.225, P = 0.239) and healthy-side KT-1000 value (H-KT, mm, t = 1.436, P = 0.172) did not significantly differ between the two groups. The proportions of cases in which the Lysholm score, IKDC and A-KT/H-KT exceeded the minimal clinically important difference (MCID) were 62.5% (20/32), 62.5% (20/32) and 93.75% (30/32), respectively.

CONCLUSION

Compared with ORIF, an arthroscopic approach for PCL tibial avulsion fractures achieves better results.

LEVEL OF EVIDENCE

Retrospective cohort study; Level II.

Clinical Effectiveness of Arthroscopy-Assisted Fixation in the Treatment of Avulsed Posterior Cruciate Ligament Injuries

Avulsed posterior cruciate ligament (PCL) injuries are complex orthopedic challenges that require careful consideration and optimal management. Arthroscopy offers advantages, including smaller incisions, reduced soft tissue disruption, reduced postoperative pain, and improved visualization of intraarticular anatomy. Arthroscopy-assisted fixation results in superior clinical outcomes. Patient-specific factors, graft choice, and timing of surgery significantly impact outcomes. Rehabilitation is vital and requires a tailored approach to restore knee function. Biomechanically, arthroscopy-assisted fixation enhances joint stability and range of motion, reducing the risk of secondary injuries. Advancements in technology and surgical techniques further improve outcomes. Concomitant injuries and incorporation are essential considerations. Arthroscopy-assisted fixation is a recommended approach, but personalized care is crucial for successful recovery. Its precision in reattaching the PCL enhances joint stability and clinical results, aligning with outcomes seen in conventional procedures. Using biocompatible materials in fixation devices has significantly reduced the risk of allergic reactions or complications. This has allowed a faster and smoother recovery process for patients undergoing arthroscopy-assisted fixation. The incorporation of physical therapy and rehabilitation programs after surgery plays a vital role in restoring joint function and preventing muscle atrophy. The combination of advanced technology, surgical techniques, and personalized care has greatly improved the success rate of arthroscopy-assisted fixation procedures. Advancements in technology further improve patient outcomes, but each case should be individually assessed to determine the most appropriate treatment approach.

Treatment of avulsion fracture of posterior cruciate ligament tibial insertion by minimally invasive approach in posterior medial knee

Objective

The study aims to explore the feasibility and clinical effect of posterior minimally invasive treatment of cruciate ligament tibial avulsion fracture.

Methods

Posterior knee minimally invasive approach was used to treat avulsion fracture of posterior cruciate ligament (PCL) tibia in 15 males and 11 females. The length of the incision, intraoperative blood loss, operation time, postoperative hospital stay, residual relaxation, and fracture healing time were analyzed to evaluate the curative effect, learning curve, and advantages of the new technology. Neurovascular complications were recorded. During the postoperative follow-up, the International Knee Joint Documentation Committee (IKDC), Lysholm knee joint score, and knee joint range of motion were recorded to evaluate the function.

Results

All 26 patients were followed up for 18-24 months, with an average of 24.42 ± 5.00 months. The incision length was 3-6 cm, with an average of 4.04 ± 0.82 cm. The intraoperative blood loss was about 45-60 ml, with an average of 48.85 ± 5.88 ml. The operation time was 39-64 min, with an average of 52.46 ± 7.64 min. The postoperative hospital stay was 2-5 days, with an average of 2.73 ± 0.87 days. All incisions healed grade I without neurovascular injury. All fractures healed well with an average healing time of 9.46 ± 1.33 weeks (range, 8-12 weeks). The Lysholm score of the affected knee was 89-98 (mean, 94.12 ± 2.49) at 12-month follow-up. The IKDC score was 87-95 with an average of 91.85 ± 2.19, and the knee range of motion was 129-148° with an average of 137.08 ± 5.59°. The residual relaxation was 1-3 mm, with an average of 1.46 ± 0.65 mm.

Conclusion

This minimally invasive method provides sufficient exposure for internal fixation of PCL tibial avulsion fractures without the surgical complications associated with traditional open surgical methods. The process is safe, less invasive, and does not require a long learning curve.

The effect of obesity on complications following isolated posterior cruciate ligament reconstruction

BACKGROUND

This study assessed the risk of 30-day complications for obese patients compared to non-obese patients undergoing isolated posterior cruciate ligament (PCL) reconstruction.

METHODS

From 2006 to 2019, the National Surgical Quality Improvement Program database was queried for patients undergoing isolated PCL reconstruction. Two patient cohorts were defined: patients with obesity (BMI ≥ 30.0 kg/m²) and patients without obesity (BMI < 30 kg/m²). Patients' baseline demographics and medical comorbidities were collected and compared between the cohorts. Postoperative outcomes were assessed using bivariate and multivariate analyses.

RESULTS

414 patients underwent PCL reconstruction. 258 patients (62.3%) were non-obese and 156 patients (37.7%) were obese. Obese patients were more likely to be older, have a higher American Society of Anesthesiologists classification, and have hypertension compared to non-obese patients (p < 0.05 for all). The rates of superficial surgical site infections, wound dehiscence, transfusion necessity, deep vein thrombosis, and re-operation were not significant between obese and non-obese patients. Following adjustment on multivariate analyses, relative to patients without obesity, those with obesity had an increased risk of admission to the hospital overnight (OR 1.66; p = 0.048).

CONCLUSIONS

To our knowledge, this is the first study to evaluate obesity on complications in isolated PCL reconstruction. Our results and the heterogeneity in the literature indicate that obesity significantly impacts the rates of hospital readmission for PCL reconstruction. Therefore, surgeons should carefully weigh the risks and benefits of operating on obese patients and plan accordingly as obese patients may require postoperative hospital admission after PCL reconstruction.

LEVEL OF EVIDENCE

III.

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.

Treatment of Posterior Cruciate Ligament Tibial Avulsion: A New Modified Open Direct Lateral Posterior Approach

The optimal operative technique for the treatment of the tibial-side avulsion injuries of the posterior cruciate ligament (PCL) is debatable. This study was aimed to evaluate the postoperative outcomes and complications if any after an open direct, posterolateral approach using cannulated cancellous screw fixation of a PCL tibial avulsion. From January 2016 to June 2018, 17 patients (14 males and 3 females) with PCL avulsion fraction treatment-who underwent open reduction and internal fixation using cannulated cancellous screws-were included in this prospective study. A direct posterolateral approach in the prone position was used in all cases. The Lysholm's knee score and International Knee Documentation Committee (IKDC) score were assessed preoperatively and during regular follow-up examinations for at least 1 year (12-20 months) postoperatively. All patients had fracture union and all of their knees were stable upon physical examination. No nerve or blood vessel injuries occurred. The mean Lysholm's scores and mean IKDC scores were improved significantly at the last follow-up. This study provides evidence that open direct posterolateral approach may be reliable for the treatment of tibial-sided bony PCL avulsion fractures. This approach can provide direct visualization of the posterior capsule and PCL avulsion site associated with good reduction and stable fixation, easy application of the screws directly from posterior to anteriorly without extensive soft tissue damage. Nevertheless, long-term follow-up is recommended.

Treatment of tibia avulsion fracture of posterior cruciate ligament with total arthroscopic internal fixation with adjustable double loop plate: A retrospective cohort study

AIM

To evaluate the effects of treating tibia avulsion fracture of the posterior cruciate ligament (PCL) by internal fixation with an adjustable double loop plate under the arthroscopic.

METHODS

Patients with a tibia avulsion fracture of the PCL were identified and were divided into two groups. X-ray, CT, and magnetic resonance imaging (MRI) were used to evaluate the injury and the fixation of the knee. The results of the range of motion (ROM), Lysholm score, International Knee Documentation Committee (IKDC) score, KT-1000, and other clinical parameters were checked and recorded, and compared through the study.

RESULTS

A total of 26 patients were identified in this study according to the inclusion and exclusion criteria. The initial fixation was achieved the fracture fragments were well fixed in all patients and the fracture healed at 3 months postoperatively. The demographics and baseline characteristics showed no differences. There were no differences between the experimental group and the control group in IKDC score (54.1±6.2 vs. 53.2±7.1, P = 0.812), Lysholm score (37.5±4.1 vs. 36.8±2.5, P = 0.636), KT-1000 score (9.8±0.6 mm vs. 9.6±0.4 mm, P = 0.401), and ROM (30±4.5˚ vs. 31±3.7˚, P = 0.723) before the surgery. Compared with the preoperative results, in the experimental group, the postoperative ROM (133.5±6.3˚, P<0.001), Lysholm scores (84.3±5.2, P = 0.001), and IKDC scores (4.5±5.1, P = 0.001) increased, and the postoperative KT-1000 scores (1.6±0.4, P = 0.001) declined, there was a significant difference. Accordingly, in the control group, the postoperative ROM (131±4.2˚, P<0.001), Lysholm scores (81.5±3.2, P = 0.001), and IKDC scores (83.6±3.7, P = 0.001) increased, and the KT-1000 scores (1.7±0.5, P = 0.001) decreased, with a significant difference. The postoperative outcomes, ROM, Lysholm scores, IKDC scores, and KT-1000 scores showed no significant differences between the two groups (P>0.799).

CONCLUSIONS

Compared with the conventional method, arthroscopic internal fixation with an adjustable double loop shows promise but requires further study.

Multi-Stage Platform for (Semi-)Automatic Planning in Reconstructive Orthopedic Surgery

Intricate lesions of the musculoskeletal system require reconstructive orthopedic surgery to restore the correct biomechanics. Careful pre-operative planning of the surgical steps on 2D image data is an essential tool to increase the precision and safety of these operations. However, the plan’s effectiveness in the intra-operative workflow is challenged by unpredictable patient and device positioning and complex registration protocols. Here, we develop and analyze a multi-stage algorithm that combines deep learning-based anatomical feature detection and geometric post-processing to enable accurate pre- and intra-operative surgery planning on 2D X-ray images. The algorithm allows granular control over each element of the planning geometry, enabling real-time adjustments directly in the operating room (OR). In the method evaluation of three ligament reconstruction tasks effect on the knee joint, we found high spatial precision in drilling point localization (ε<2.9mm) and low angulation errors for k-wire instrumentation (ε<0.75∘) on 38 diagnostic radiographs. Comparable precision was demonstrated in 15 complex intra-operative trauma cases suffering from strong implant overlap and multi-anatomy exposure. Furthermore, we found that the diverse feature detection tasks can be efficiently solved with a multi-task network topology, improving precision over the single-task case. Our platform will help overcome the limitations of current clinical practice and foster surgical plan generation and adjustment directly in the OR, ultimately motivating the development of novel 2D planning guidelines.

Biomechanical evaluation of a novel transtibial posterior cruciate ligament reconstruction using high-strength sutures in a porcine bone model

Background:

Multiple techniques are commonly used for posterior cruciate ligament (PCL) reconstruction. However, the optimum method regarding the fixation of PCL reconstruction after PCL tears remains debatable. The purpose of this study was to compare the biomechanical properties among three different tibial fixation procedures for transtibial single-bundle PCL reconstruction.

Methods:

Thirty-six porcine tibias and porcine extensor tendons were randomized into three fixation study groups: the interference screw fixation (IS) group, the transtibial tubercle fixation (TTF) group, and TTF + IS group (n = 12 in each group). The structural properties of the three fixation groups were tested under cyclic loading and load-to-failure. The slippage after the cyclic loading test and the stiffness and ultimate failure load after load-to-failure testing were recorded.

Results:

After 1000 cycles of cyclic testing, no significant difference was observed in graft slippage among the three groups. For load-to-failure testing, the TTF + IS group showed a higher ultimate failure load than the TTF group and the IS group (876.34 ± 58.78 N vs. 660.92 ± 77.74 N [P < 0.001] vs. 556.49 ± 65.33 N [P < 0.001]). The stiffness in the TTF group was significantly lower than that in the IS group and the TTF + IS group (92.77 ± 20.16 N/mm in the TTF group vs. 120.27 ± 15.66 N/m in the IS group [P = 0.001] and 131.79 ± 17.95 N/mm in the TTF + IS group [P < 0.001]). No significant difference in the mean stiffness was found between the IS group and the TTF + IS group (P = 0.127).

Conclusions:

In this biomechanical study, supplementary fixation with transtibial tubercle sutures increased the ultimate failure load during load-to-failure testing for PCL reconstruction.

Posterolateral Complex Reconstruction With Distal Femoral Varus Opening-Wedge Osteotomy for Unstable Neglected Multiligamentous Knee Injury With Valgus Malalignment

We presented a case of a 25-year-old woman with early posttraumatic degenerative change to the articular cartilage accompanied with valgus malalignment despite receiving anterior cruciate ligament reconstruction after a multiligamentous injury sustained 2 years earlier. Rapid deteriorating valgus malalignment may result from chronic instability and intra-articular bone loss. Simultaneous distal femoral varus osteotomy and posterolateral complex reconstruction were performed during a single surgery. Six months after the surgery, the patient could walk briskly and climb stairs without any discomfort. Salvage procedures and biological reconstruction could be the primary choice for young patients to recover their knee function while avoiding joint replacement.

[Comparative study on effectiveness of posterior-posterior triangulation technique and anteroposterior approach for arthroscopic posterior cruciate ligament reconstruction]

Objective

To investigate the effectiveness of the posterior-posterior triangulation technique for arthroscopic posterior cruciate ligament (PCL) reconstruction by comparing with the anteroposterior approach.

Methods

Retrospective analysis was performed on 40 patients who underwent arthroscopic PCL reconstruction between February 2016 and February 2020. The PCLs were reconstructed via anteroposterior approach in 20 patients (anteroposterior approach group) and posterior-posterior triangulation technique in 20 patients (posterior-posterior triangulation technique group). There was no significant difference in gender, age, cause of injury, injury side, disease duration, preoperative International Knee Documentary Committee (IKDC) score, and Lysholm score between the two groups ( P>0.05). The operation time, surgical complications, and postoperative posterior drawer test, Lysholm score, and IKDC score were recorded and compared between the two groups.

Results

The operation time was (65.25±10.05) minutes in the anteroposterior approach group and (56.15±8.15) minutes in the posterior-posterior triangulation technique group, and the difference was significant ( t=3.145, P=0.003). All incisions healed by first intention, and there was no complication such as vascular and nerve injuries or infection. Patients were followed up (27.05±11.95) months in the anteroposterior approach group and (21.40±7.82) months in the posterior-posterior triangulation technique group, with no significant difference ( t=1.770, P=0.085). At last follow-up, the posterior drawer tests were positive in 4 cases (3 cases of stageⅠand 1 case of stage Ⅱ) of the anteroposterior approach group and in 1 case (stageⅠ) of the posterior-posterior triangulation technique group, showing no significant difference between the two groups ( P=0.342). At last follow-up, Lysholm score and IKDC score in both groups were significantly higher than those before operation ( P<0.05). The above functional scores in the posterior-posterior triangulation technique group were significantly higher than those in the anteroposterior approach group ( P<0.05). Imaging reexamination showed that the position, shape, and tension of the grafts were well in both groups, and the grafts were covered with the synovium in the posterior-posterior triangulation technique group, the meniscofemoral ligaments were well preserved. There was no re-rupture of the reconstructed ligament during follow-up.

Conclusion

Compared to the anteroposterior approach, the posterior-posterior triangulation technique provides a clearer view under arthroscopy, no blind spot, sufficient operating space, and relative safety. Moreover, it is easier to retain the remnant and the meniscofemoral ligaments, and can obtain good short-term effectiveness.

Conversion rates and timing to total knee arthroplasty following anterior cruciate ligament reconstruction: a US population-based study

PURPOSE

To define the rate of subsequent TKA following ACLR in a large US cohort and to identify factors that influence the risk of later undergoing TKA after ACLR.

METHODS

The California's Office of Statewide Health Planning and Development (OSHPD) database was queried from 2000 to 2014 to identify patients who underwent primary ACLR (ACL group). An age-and gender-matched cohort that underwent appendectomy was selected as the control group. The cumulative incidence of TKA was calculated and ten-year survival was investigated using Kaplan-Meier analysis with failure defined as conversion to arthroplasty. Univariate and multivariate analyses were performed to explore the risk factors for conversion to TKA following ACLR.

RESULTS

A total of 100,580 ACLR patients (mean age 34.48 years, 66.1%male) were matched to 100,545 patients from the general population. The ACL cohort had 1374 knee arthroplasty events; conversion rate was 0.71% at 2-year follow-up, 2.04% at 5-year follow-up, and 4.86% at 10-year follow-up. This conversion rate was higher than that of the control group at all time points, with an odds ratio of 3.44 (p<0.001) at 10-year follow-up. Decreasing survivorship following ACLR was observed with increasing age, female gender, and worker's compensation insurance, while increased survivorship was found in patients of Hispanic and Asian Pacific Islander racial heritage and those who underwent concomitant meniscal repair.

CONCLUSIONS

In this US statewide study, the rate of TKA after ACLR is higher than reported elsewhere, with significantly increased odds when compared to a control group. Age, gender, concomitant knee procedures and other socioeconomic factors influence the rate of conversion to TKA following ACLR.

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.

Evolving evidence in the treatment of primary and recurrent posterior cruciate ligament injuries, part 2: surgical techniques, outcomes and rehabilitation

Isolated and combined posterior cruciate ligament (PCL) injuries are associated with severe limitations in daily, professional, and sports activities as well as with devastating long-term effects for the knee joint. As the number of primary and recurrent PCL injuries increases, so does the body of literature, with high-quality evidence evolving in recent years. However, the debate about the ideal treatment approach such as; operative vs. non-operative; single-bundle vs. double-bundle reconstruction; transtibial vs. tibial inlay technique, continues. Ultimately, the goal in the treatment of PCL injuries is restoring native knee kinematics and preventing residual posterior and combined rotatory knee laxity through an individualized approach. Certain demographic, anatomical, and surgical risk factors for failures in operative treatment have been identified. Failures after PCL reconstruction are increasing, confronting the treating surgeon with challenges including the need for revision PCL reconstruction. Part 2 of the evidence-based update on the management of primary and recurrent PCL injuries will summarize the outcomes of operative and non-operative treatment including indications, surgical techniques, complications, and risk factors for recurrent PCL deficiency. This paper aims to support surgeons in decision-making for the treatment of PCL injuries by systematically evaluating underlying risk factors, thus preventing postoperative complications and recurrent knee laxity. LEVEL OF EVIDENCE: V.

Posteromedial versus direct posterior approach for posterior cruciate ligament avulsion – A comparative study

Background/Purpose:

Open reduction of acute avulsion of posterior cruciate ligament (PCL) fragment may be achieved through direct posterior approach or posteromedial approach. The aim of our study was to compare these two techniques for fixation of avulsed PCL fragment. Our primary study objective was to study that which of the above techniques provides a better screw placement on post-operative radiographs. The secondary objectives were to study any statistically significant differences in surgical time, blood loss, incidence of neurovascular injury, bone union and functional knee scores in the above two techniques.

Materials and methods:

This is a prospective, comparative, interventional, single tertiary referral centre-based study from November 2014 to May 2019. Patients in the direct posterior group were treated with the approach described by Abbott and Carpenter, and patients in the posteromedial group were treated with the approach described by Burks and Schaffer. Screw placement was assessed on anteroposterior (AP) and lateral knee X-rays. Blood loss was studied using haemoglobin balance method. Functional scores were recorded preoperatively and at 1-year follow up using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) knee scores.

Results:

The posterior group showed better screw placement angle compared to the posteromedial group. In the AP plane, the mean angle of screw placement and fracture line was 83° compared to 59° in the posteromedial group. Average fracture union time, post-operative range of motion and post-operative WOMAC scores were not statistically different in both groups. There were no cases of neurovascular complication, deep vein thrombosis and superficial or deep surgical site infection in any group.

Conclusion:

Direct posterior approach to PCL avulsion provides better screw placement angle compared to the posteromedial approach, which might result in better interfragmentary compression at the avulsion site. However, the two approaches did not differ statistically in terms of functional scores of patients reported at 1 year.

Microstructural and Mechanical Properties of Grafts Commonly Used for Cruciate Ligament Reconstruction

BACKGROUND

Injuries to the anterior cruciate ligament and posterior cruciate ligament are common, and often are treated with reconstruction. Limited quantitative data are available describing material properties of grafts used for reconstructions such as the bone-patellar tendon-bone (BPTB), hamstring tendon (HS), and quadriceps tendon (QT). The purpose of this study was to quantify and compare microstructural and mechanical properties of BPTB, HS, and QT grafts.

METHODS

Forty specimens (13 BPTB, 13 HS, and 14 QT grafts) from 24 donors were used. Specimens were subjected to preconditioning, stress relaxation, and ramp to failure. Mechanical parameters were calculated for each sample, and polarization imaging was used to evaluate the direction and strength of collagen fiber alignment during testing.

RESULTS

QT had the largest modulus values, and HS had the smallest. BPTB exhibited the least disperse collagen organization, while HS were the least strongly aligned. Microstructural properties showed more strongly aligned collagen with increasing load for all grafts. All tissues showed stress relaxation and subtle microstructural changes during the hold period.

CONCLUSIONS

The mechanical and microstructural properties differed significantly among BPTB, HS, and QT grafts. QT exhibited the largest moduli and greatest strength of collagen alignment, while HS had the smallest moduli and least strongly aligned collagen.

CLINICAL RELEVANCE

This study identified mechanical and microstructural differences among common grafts and between these grafts and the cruciate ligaments they replace. Further research is needed to properly interpret the clinical relevance of these differences.

[Modified arthroscopic technique to replace the posterior cruciate ligament in multiligament knee injuries : Results compared to open tibial inlay technique]

BACKGROUND

There is no standard procedure regarding surgical treatment of multiligament knee injuries involving rupture of the posterior cruciate ligament.

OBJECTIVE

Does the modified and purely arthroscopic operation technique show similarly good results compared to the familiar open tibial inlay technique?

METHODS

A total of four patients were surgically treated using the open tibial inlay technique (group A) and seven using the modified arthroscopic approach (group B). The prospectively designed follow-up examination comprised the Lysholm score, the subjective questionnaire of the International Knee Documentation Committee (IKDC) score as well as the specifically extended Orthopedic Working Group Knee (OAK) score for clinical assessment. Tests on translational movability of the knee joint were performed with the Rolimeter®. The level of statistical significance alpha was set at 5%.

RESULTS

The follow-up examination took place on average 28.5 ± 19.60 months and 30.6 ± 26.26 months postoperatively in groups A and B, respectively. Groups A and B recorded mean 70.3 ± 5.32 and 69.6 ± 19.82 points in the Lysholm score, respectively. In the subjective IKDC score group A showed 67.3 ± 7.76 points and group B 65.9 ± 12.35 points. The OAK score was 77.5 ± 6.10 points in group A and 75.3 ± 11.31 points in group B. The side difference in the posterior drawer test was 1.75 ± 1.192 mm in group A and 2.50 ± 2.160 mm in group B. In the reverse Lachman test differences of 2.37 ± 2.175 mm and 3.22 ± 2.059 mm were measured in groups A and B, respectively. All values showed no significant differences between the two evaluated groups.

CONCLUSION

The results of the two operation techniques were not significantly different. The arthroscopic approach is therefore regarded as the preferred method in this institute.

Revision of failed-posterior cruciate ligament (PCL) reconstruction due to tibial tunnel misplacement: A case report

Introduction

Posterior cruciate ligament (PCL) reconstruction failure is a rare condition found. The failure caused by some factors, including improper graft tunnel placement. Although the proper tibial tunnel placement in PCL reconstruction is still controversial, make the tunnel placement anatomically essential to decrease the risk of failure. The use of PCL jig only to guide the direction of tibial tunnel does not always give good results.

Presentation of case

We report a case of 29 year old male with total rupture of ACL and PCL that underwent reconstruction for both ligaments. We found the failure of the PCL graft 2 years after the surgery was related to the tibial tunnel placement which was placed not in proper anatomical site. We performed revision PCL surgery with transseptal portal technique to ensure the tibial tunnel is placed in appropriate position.

Discussion

The cause of failure was associated with misposition of tibial tunnel. The tibial tunnel performed in previous surgery was too anterior than the anatomical foot print. This condition might be caused by surgical technique which depending only on PCL jig to guide the tibial tunnel direction and location. We performed transseptal portal technique get better visualization on the posterior aspect of the knee to achieve the proper direction of tibial tunnel.

Conclusion

The use of PCL jig as the only tools for guiding tibial tunneling should be avoided. Additional tool such as transseptal portal is required to ensure the proper anatomical tibia tunnel in order to achive good PCL graft placement.

All-Arthroscopic Posterior Cruciate Ligament Distal Reattachment With Extracortical Fixation

Avulsion fractures of the posterior cruciate ligament (PCL) are a rare, but serious, knee pathology. Early surgical treatment is regarded as necessary to maintain knee stability. Recommended management involves open reduction with internal fixation through a posterior approach. However, open surgeries are associated with a greater risk of complications. Current data suggest excellent outcomes for arthroscopic-assisted fixation, with a low complication rate. The purpose of this technical note is to present an all-arthroscopic PCL distal reattachment with extracortical fixation technique. This technique provides precise fracture reduction, is easily reproducible, and is relatively safe to treat PCL tibial avulsion fractures.

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.

Outcome of screw post fixation of neglected posterior cruciate ligament bony avulsions

BACKGROUND

Contrary to acute posterior cruciate ligament (PCL) bony tibial avulsions, surgical management of chronic injuries is technically challenging and appears to be controversial. We sought to assess the outcome of a novel screw post augmentation technique in neglected cases.

METHODS

16 patients were followed up in a tertiary single-center retrospective study. The bony fragment was fixed using a lag screw with a spiked washer and an additional screw post through an open posterior approach. The pre- and postoperative knee range of movement (ROM), laxity, and modified Tegner-Lysholm (TL) scores were compared.

RESULTS

The median time from injury to surgery was 10 weeks (range, 3-260). The mean clinical follow-up time was 24.25 ± 9.21 months. At the final follow-up, the mean knee ROM flexion was 130° ± 11.55° with no extension lag. 3 patients had grade 1 laxity. The TL grade was predominantly excellent, and the overall median score improved from 76 preoperatively to 95 postoperatively (p < 0.0004). Bony union was achieved in all cases.

CONCLUSION

The described screw post fixation technique results in an excellent outcome for these rare injuries.

LEVEL OF EVIDENCE

Level IV, case series.

Effect of Activity at Time of Injury and Concomitant Ligament Injuries on Patient-Reported Outcome After Posterior Cruciate Ligament Reconstruction

Background:

The outcomes after posterior cruciate ligament reconstruction (PCLR) have been shown to be inferior to those of anterior cruciate ligament reconstruction. There is a lack of knowledge regarding prognostic factors of PCLR outcomes.

Purpose:

To explore the effect of injury mechanism and concomitant ligament injuries on patient-reported outcomes at 2-year follow-up after PCLR.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

A total of 373 patients who underwent primary PCLR and who were registered in the Norwegian Knee Ligament Registry were included. The Knee injury and Osteoarthritis Outcome Score (KOOS) was used as the patient-reported outcome measure. At 2-year follow-up, 252 patients (68%) had completed the KOOS. Multiple regression analysis was used to evaluate the effects of injury activity and multiligament injuries on the KOOS outcomes.

Results:

In the adjusted and unadjusted regression analyses, patients injured during sports reported significantly better outcome at 2-year follow-up after PCLR than patients injured during other activities (P < .001) according to all KOOS subscales. Adjusted analysis was as follows for the KOOS subscales: Symptoms (regression coefficient [β], 7.0; 95% CI, 1.9-12.2), Pain (β, 13.4; 95% CI, 8.0-18.9), Activities of Daily Living (β, 12.6; 95% CI, 7.1-18.1), Sport/Recreation (β, 15.3; 95% CI, 8.0-22.5), and Quality of Life (β, 13.5; 95% CI, 7.1-20.0). In the unadjusted analysis, patients with isolated PCL injuries reported higher scores in the Sport/Recreation subscale (β, –7.9; 95% CI, –15.5 to –0.3). The difference was not significant in the adjusted analysis. No other significant differences in KOOS outcomes were found between isolated and multiligament injuries.

Conclusion:

Patients injured in sports reported better outcomes at 2 years after PCLR as compared with patients injured in other activities. Multiligament injuries involving the PCL do not seem to predict a worse outcome than for isolated PCL injuries.

Acute posterior cruciate ligament injuries: effect of location, severity, and associated injuries on surgical management

OBJECTIVE

To correlate MRI findings of patients with posterior cruciate ligament (PCL) injury and surgical management.

MATERIALS AND METHODS

A retrospective search yielded 79 acute PCL injuries (36 ± 16 years old, 21 F, 58 M). Two independent readers graded PCL tear location (proximal, middle, or distal third) and severity (low-grade or high-grade partial/complete) and evaluated injury of other knee structures. When available, operative reports were examined and the performed surgical procedure was compared with injury grade, location, and presence of associated injuries.

RESULTS

The most commonly injured knee structures in acute PCL tears were posterolateral corner (58/79, 73%) and anterior cruciate ligament (ACL) (48/79, 61%). Of the 64 patients with treatment information, 31/64 (48%) were managed surgically: 12/31 (39%) had PCL reconstruction, 13/31 (42%) had ACL reconstruction, 10/31 (32%) had posterolateral corner reconstruction, 9/31 (29%) had LCL reconstruction, 8/31 (26%) had meniscectomy, and 8/31 (26%) had fixation of a fracture. Proximal third PCL tear and multiligamentous injury were more commonly associated with surgical management (P < 0.05). Posterolateral and posteromedial corner, ACL, collateral ligament, meniscus, patellar retinaculum, and gastrocnemius muscle injury, and fracture were more likely to result in surgical management (P < 0.05). Patients with high-grade partial/complete PCL tear were more likely to have PCL reconstruction as a portion of surgical management (P < 0.05).

CONCLUSIONS

Location of PCL tear and presence of other knee injuries were associated with surgical management while high-grade/complete PCL tear grade was associated with PCL reconstruction. MRI reporting of PCL tear location, severity, and of other knee structure injuries is important for guiding clinical management.

Fabrication of alignment polycaprolactone scaffolds by combining use of electrospinning and micromolding for regulating Schwann cells behavior

In the present study, a new approach for fabricating micropatterned polycaprolactone (PCL) scaffolds with ridge/groove structure on the surface was developed by combining use of electrospinning and micromolding method. A series of physicochemical properties, including morphology, wettability, component, crystal pattern and mechanical properties, of prepared PCL scaffolds were characterization, respectively. Stability of the micropatterned PCL scaffolds was measured using phosphate buffer solution immersion for a certain period. Then, the regulating effects of the micropatterned PCL scaffolds on attachment, orientation and normal biological function of Schwann cells were evaluated. And the protein adsorption behavior in various PCL scaffolds was also detected. The results showed that the micropatterned PCL scaffolds demonstrated a porous micro/nano complex structure with enhanced hydrophobicity and mechanical properties as a function of electrospun flow-rate of PCL solution. The micropatterned PCL scaffolds possessed good stability and could effectively regulate the attachment and orientation of Schwann cells at the early stage after cell culture. Importantly, the electrospun flow-rate of PCL solution was found to play an important role in scaffold properties, cell behavior and protein adsorption. The micropatterned scaffolds with a flow-rate of PCL solution at 0.12 mL h^-1 demonstrated the better regulation on Schwann cells attachment and alignment without negatively affect the normal biological function of the cells. To the best of our knowledge, this is the first report of combining use of electrospinning and micromolding method for preparing artificial nerve implants. The study is anticipated to have potential application in peripheral nerve and other tissue engineering. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 3123-3134, 2018.

REHABILITATION FOLLOWING ISOLATED POSTERIOR CRUCIATE LIGAMENT RECONSTRUCTION: A LITERATURE REVIEW OF PUBLISHED PROTOCOLS

BACKGROUND

Surgical outcomes following isolated posterior cruciate ligament reconstruction (PCLR) have been noted to be less satisfactory than the anterior cruciate ligament. Limited understanding of optimal rehabilitation has been implicated as a contributing factor.

HYPOTHESIS/PURPOSE

The purpose of this review was to gather the literature related to isolated PCLR rehabilitation, extract and summarize current rehabilitation guidelines, identify timeframes and functional measurements associated with common rehabilitation topics and provide recommendations for future research.

STUDY DESIGN

Literature review.

METHODS

A literature review was performed for scientific publications that include a detailed rehabilitation program following isolated PCLR, published between January 2005 and March 2018. Data related to weight-bearing, knee range of motion (ROM), brace usage, specific exercise recommendations and suggestions for return to running and sport activities were extracted and categorized.

RESULTS

A total of 44 articles met inclusion criteria. Post-operative weight-bearing was discussed in 35 articles with recommendations ranging from no restriction to 12 weeks of limitations. Forty-two articles recommended the use of immediate post-operative bracing, the majority of which positioned the knee in full extension, with duration of use ranging from one to 12 weeks post-operatively. Although 30 articles offered detailed descriptions of ROM activity, there was significant variability in timing of initiation, angular excursion and progression of range of motion. Suggested timeframes for returning to sports activity ranged from four to 12 months, with only four articles providing specific objective strength or functional performance criteria necessary for progression.

CONCLUSIONS

There is substantial variation in nearly all aspects of published descriptors of rehabilitation following isolated PCLR. Most protocols are based upon biomechanical principles and clinical expertise, relying solely on timeframe from surgery to support rehabilitation decision making. Evidence to compare patient outcomes with specific loading, ROM progression and exercise strategies is currently lacking. Only a small number of protocols incorporate the use of specific objective performance goals to facilitate return to sport decision making.

Graft Considerations in Posterior Cruciate Ligament Reconstruction

PURPOSE OF REVIEW

To highlight current and established concepts regarding PCL injury and reconstruction.

RECENT FINDINGS

Recent biomechanical and clinical studies have brought attention to improved surgical techniques and clinical outcomes of PCL reconstruction. In contrast to anterior cruciate ligament (ACL) injuries, isolated posterior cruciate ligament (PCL) injuries occur much less frequently and have traditionally been treated non-operatively. Even when a PCL injury meets operative indications, outcomes of PCL reconstruction historically do not match the success rates of ACL reconstruction procedures. As such, there remains controversy regarding appropriate indications and techniques for surgical repair leading to a paucity of conclusive data regarding surgical outcomes. Recently, however, there has been an increase in focus on the role of the PCL in proper knee biomechanics and negative long-term sequelae of chronic PCL insufficiency. This improved understanding has led to advancements in surgical technique and graft options for PCL reconstruction.

Autograft Versus Allograft for Posterior Cruciate Ligament Reconstruction: An Updated Systematic Review and Meta-analysis

BACKGROUND

Multiple studies have demonstrated a higher risk of graft failure after anterior cruciate ligament reconstruction with allograft, but limited data are available comparing outcomes of posterior cruciate ligament reconstruction (PCLR) with autograft versus allograft.

PURPOSE

To compare the clinical outcomes of autograft versus allograft for primary PCLR.

STUDY DESIGN

Systematic review.

METHODS

A systematic review was performed by searching PubMed, the Cochrane Library, and EMBASE to locate studies (level of evidence I-III) comparing clinical outcomes of autograft versus allograft in patients undergoing primary PCLR with the conventional transtibial technique. Search terms used were "posterior cruciate ligament," "autograft," and "allograft." Patients were evaluated based on graft failure rate, examination of knee laxity, and patient-reported outcome scores (Lysholm, Tegner, subjective International Knee Documentation Committee [IKDC], and objective IKDC scores).

RESULTS

Five studies (2 level II, 3 level III) were identified that met inclusion criteria, including a total of 132 patients undergoing PCLR with autograft (semitendinosus-gracilis or bone-patellar tendon-bone) and 110 patients with allograft (tibialis anterior, Achilles tendon, or bone-patellar tendon-bone). No patients experienced graft failure. Average anteroposterior (AP) knee laxity was significantly higher in allograft patients (3.8 mm) compared with autograft patients (3.1 mm) ( P < .01). Subjective IKDC, Lysholm, and Tegner scores improved for both groups across studies, without a significant difference in improvement between groups except in one study, in which Lysholm scores improved to a significantly greater extent in the autograft group ( P < .01).

CONCLUSION

Patients undergoing primary PCLR with either autograft or allograft can be expected to experience improvement in clinical outcomes. Autograft patients experienced less AP knee laxity postoperatively, although the clinical significance of this is unclear and subjective outcomes improved substantially and to a similar degree in both groups.

Management of Posterior Cruciate Ligament Tibial Avulsion Injuries: A Systematic Review

BACKGROUND

Tibial-sided avulsion injuries of the posterior cruciate ligament (PCL) generally require surgical intervention. No consensus exists concerning the optimal surgical treatment approach for these injuries.

PURPOSE

To perform a systematic review investigating the open and arthroscopic surgical treatment modalities, outcomes, and complications of PCL tibial-sided bony avulsions.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

The authors performed a systematic review of the literature utilizing PubMed and EMBASE from 1975 to present outlining open versus arthroscopic surgical repair of PCL bony avulsion injuries and comparing subjective and objective postoperative patient-reported outcomes, including Tegner, IKDC (International Knee Documentation Committee), and Lysholm scoring systems, as well as rates of patient complications. The quest was performed in June 2016, and searched terms included posterior cruciate ligament, PCL, bony, avulsion(s), tibial-sided, open, and arthroscopic. Inclusion criteria included English-language studies involving surgical fixation strategies for PCL tibial-sided bony avulsions. Exclusion criteria included non-English language, case studies/case series, and subject matter not pertaining to PCL bony avulsions.

RESULTS

Twenty-eight articles comprising 637 patients met the criteria and were included in the final review. PCL injuries with a tibial-sided avulsion were the result of motor vehicle accidents in 68.4% of patients, with 59.0% of these injuries resulting from motorcycle accidents. The arthroscopic group had better IKDC grade A scores (78.9%), indicating a normal knee postoperatively, as compared with the open group (65.9%). The postoperative Lysholm scores were similar between the groups, with a mean of 95.0 in the arthroscopic group and 92.8 in the open group. The arthroscopic group also reported 100% return to preinjury level of activity, compared with 86.2% in the open group. The most common complication in both groups was arthrofibrosis, which was reported more often in the arthroscopic group (0%-35%) versus the open treatment group (0%-25%).

CONCLUSION

In patients with displaced tibial-sided PCL avulsion fractures treated operatively, surgical approaches render similar outcomes and risks. While the arthroscopic group had somewhat higher subjective and objective knee outcome scores, it demonstrated a slightly higher rate of arthrofibrosis. The clear advantage of the arthroscopic approach is that concomitant intra-articular injuries seen on preoperative magnetic resonance imaging, such as meniscal tears or osteochondral loose fragments, can be addressed at the time of the index operation.

A Posterior Approach to Open Reduction and Internal Fixation of Displaced Posterior Cruciate Ligament Tibial Osseous Avulsions

Background

The true prevalence of displaced tibial-sided avulsion injuries of the posterior cruciate ligament (PCL; Video 1) is unknown, and the majority of data regarding management has been published in areas other than the Western world, such as China and India (perhaps due to the higher prevalence of two-wheeler motorcycle accidents in these areas). Despite the rarity of data, a better understanding of the approach, fixation techniques, and outcomes is necessary to provide quality patient care. These injuries generally require surgical intervention as nonoperative management leads to complications-specifically, knee arthrofibrosis^1,2. There is no consensus regarding the optimal surgical approach for these injuries. A recent systematic review demonstrated that both open and arthroscopic surgical treatment provide satisfactory complication rates and outcomes in the majority of cases³. However, the arthroscopic approach can be performed by only a highly skilled arthroscopist; thus, in this article we focus on the open approach to reach a broader audience of capable surgeons.

Description

The principal steps for open reduction and internal fixation of the tibial avulsion fracture include the following:Place the patient in a prone position and utilize a curvilinear L-shaped incision with the longitudinal portion over the medial head of the gastrocnemius muscle and the transverse portion starting distal to the joint line and extending laterally past the midline.Develop the interval between the semimembranosus and medial gastrocnemius muscles, as originally described by Burks and Schaffer⁴. Lateral retraction of the gastrocnemius muscle exposes the posterior aspect of the capsule, allowing for a vertical capsular incision to adequately visualize the avulsed osseous fragment.Prepare the osseous bed and remove hematoma and/or debris.Reduce the avulsed fragment and obtain provisional fixation with Kirschner wires.Confirm reduction under fluoroscopy with emphasis on sagittal plane alignment.Obtain definitive fixation with the method dictated by the fracture orientation. Options include screw(s) with or without a washer, sutures, Kirschner wires, staples, and toothed plates^2,5-7.

Alternatives

An arthroscopic approach can be performed, with results that are similar to those of an open procedure, but considerable expertise is required to perform this procedure arthroscopically. Nonsurgical management is not recommended as it frequently leads to loss of knee motion.

Rationale

The exact operative indications for PCL injuries remain in question, but we believe that displaced tibial avulsion injuries at the PCL attachment always require operative treatment.

Protruding anterior medial meniscus-An indirect sign of posterior cruciate ligament deficiency

BACKGROUND

to examine if PROTruding of the Anterior Medial Meniscus (PROTAMM) could be an indirect sign of PCL deficiency by comparing PROTAMM to passive posterior tibial sagging (PSS) for chronic PCL rupture on routine MRI.

METHODS

Patients with PCL reconstruction between 2011 and 2016 were included in a case control study. Primarily cases with combined ACL/PCL injury were excluded. Secondary exclusion criteria were bony fractures, medial meniscus pathology and poor quality MRIs. Three (blinded) observers reviewed the pre-operative MRIs according to a pre-defined protocol.

RESULTS

After applying the inclusion and primary exclusion criteria 16 patients were identified in the PCL rupture group. The control group consisted of 15 patients. After reviewing the MRIs, 6 were excluded due to secondary exclusion criteria. Mean PPS measured 4.8 mm (± 4.4 mm) in the PCL rupture group and 1.8 mm (±2.9 mm) in the control group, p = 0.05. Mean PROTAMM was 3.6 mm (±0.6 mm) in the PCL rupture group and 0.7 mm (±0.9 mm) in the control group, p = 0.004.

CONCLUSION

We found a mean PROTAMM of 3.6 mm in patients with PCL rupture. We suggest that this sign, after knee injury in an otherwise normal medial meniscus, is a promising indirect sign of PCL deficiency compared to PPS. Implementation of this sign in clinical practice may improve the sensitivity of routine non-weight bearing MRI in identifying PCL deficient knees.

Long-term outcomes after arthroscopic single-bundle reconstruction of the posterior cruciate ligament: A 7-year follow-up study

Objective

Arthroscopy is the most popular technique in posterior cruciate ligament (PCL) reconstruction surgery. However, no consensus on long-term outcomes after arthroscopic PCL reconstruction has been reached. This study was performed to evaluate the long-term outcomes after arthroscopic autologous hamstring or allogeneic tendon single-bundle reconstruction of the PCL.

Methods

Fifty-eight patients who underwent arthroscopic PCL reconstruction in Anhui, China from 2007 to 2009 were included. The follow-up period ranged from 56 to 83 months. During the follow-up, the Lysholm knee score and Tegner activity score were used to assess knee function. The KT-2000 arthrometer (MEDmetric Corp., San Diego, CA, USA) was used to assess the stability of the reconstructed PCL.

Results

The mean Lysholm score, mean Tegner score, and mean forward and backward displacements were not significantly different between the final follow-up and 1 year after the surgery. Additionally, no significant differences were observed in any of the above-mentioned parameters between autologous and allogeneic reconstruction at the final follow-up.

Conclusion

Both autologous and allogeneic reconstruction had few complications and satisfactory long-term outcomes.

Isolated posterior cruciate ligament tears: an update of management

Isolated posterior cruciate ligament (PCL) tears are much less frequent than anterior cruciate ligament (ACL) tears.

Abrupt posterior tibial translation (such as dashboard impact), falls in hyperflexion and direct hyperextension trauma are the most frequent mechanisms of production.

The anterolateral bundle represents two-thirds of PCL mass and is reconstructed in single-bundle techniques.

The PCL has an intrinsic capability for healing. This is the reason why, nowadays, the majority of isolated PCL tears are managed non-operatively, with rehabilitation and bracing.

Recent studies have focused on double-bundle reconstruction techniques, as they seem to restore knee kinematics.

No significant clinical differences have been established between single versus double-bundle techniques, autograft versus allograft, transtibial tunnel versus tibial inlay techniques or remnant-preserving versus remnant-release techniques.

Cite this article: EFORT Open Rev 2017;2:89-96. DOI: 10.1302/2058-5241.2.160009

Optimal management of posterior cruciate ligament injuries: current perspectives

Background

The optimal management of posterior cruciate ligament (PCL) injuries is debated by orthopedic surgeons. A natural history study (NHS) of acute, isolated PCL tears in patients with a mean follow-up of 14.3 years was previously published. The purpose of this study was to compare and contrast the results of the NHS study with those of other studies with similar follow-up time after operative and nonoperative management of isolated PCL tears.

Material and methods

With reviewing the literature, six operative management and six nonoperative management studies were found for treating isolated PCL injuries. We analyzed the subjective and objective outcomes of these 12 studies and compared them to the results of the NHS to determine optimal management of PCL injuries.

Results

Final follow-up times ranged from a mean of 6.2 to 15 years in the nonoperative studies and 6.3 to 12 years in the operative studies. Side-to-side differences in laxity following surgical management ranged from 1.1 to 7 mm on KT-1000 arthrometer testing and 2.8 to 4.7 mm on Telos stress testing. Tegner scores at final follow-up ranged from 6.6 to 7.7 in nonoperative studies and 5.7 to 7.4 in operative studies. International Knee Documentation Committee scores were 73.4, 82.7, and 84 in nonoperative studies and 65 and 87 in the operative studies. Lysholm scores were 85.2 in the nonoperative study and ranged from 81 to 92.1 in operative studies. Osteoarthritis was reported with ranges from 17% to 88% in nonoperative studies and 13.3% to 63.6% in operative studies.

Conclusion

We found that the subjective and objective results in the NHS compare favorably to those of outcomes for PCL reconstruction. Unless a technique is found that can completely restore knee stability, it is unlikely that simply reducing posterior laxity will improve outcomes or prevent the development of osteoarthritis.

What Role Does Low Bone Mineral Density Play in the "Killer Turn" Effect after Transtibial Posterior Cruciate Ligament Reconstruction?

OBJECTIVE

To explore the mechanism of the "killer turn", which is reported to be a reason for postoperative residual laxity after transtibial posterior cruciate ligament (PCL) reconstruction, in a low bone mineral density (BMD) condition.

METHODS

A total of 80 skeletally mature female New Zealand white rabbits were included for biomechanical evaluation after transtibial PCL reconstructions. The subjects were equally divided into low BMD (n = 40) and control groups (n = 40). Rabbits in the low BMD group were treated with surgery and drug injection to establish an osteoporotic model. Rabbits in the control group received sham surgeries and no injection. All assignments were conducted randomly according to random numbers generated by a computer. All grafts were then subjected to biomechanical testing with an MTS model-858 Mini Bionix servohydraulic materials testing machine (MTS Systems, Minneapolis, Minnesota, USA). The experimental outcomes were the increment of total graft displacement, tunnel inlet enlargement, graft elongation, stiffness and failure load of the two groups, and the comparison between them.

RESULTS

Among the 80 subjects, 1 subject of the low BMD group failed at the 30th cycle by proximal tibial fracture and 1 subject of the control group failed at the 20th cycle for the same reason. As a result, 39 subjects of the low BMD group and 39 subjects of the control group survived the cyclic loading test. Compared with the control group, the low BMD group demonstrated significantly larger total graft displacement ( P = 0.006) and tunnel inlet enlargement ( P = 0.041) than the control group. The number of subjects with less than 10% enlargement was significantly greater (57.1%) in the control group than in the low BMD group ( P = 0.004). In the load-to-failure test, 26 (66.7%) subjects in the low BMD group failed by proximal tibial fracture (around the tunnel), 6 (15.4%) at the mounting site, 5 (12.8%) at the fixation site, and only 2 (5.1%) failed at the "killer turn." In the control group, 20 (51.3%) failed at the "killer turn," 9 (23.1%) at the proximal tibia (around the tunnel), 5 (12.8%) at the mounting site, and 5 (12.8%) at the fixation site. There were significantly fewer failures (10.0%) at the "killer turn" ( P = 0.000) and 155.6% more for the para-tunnel fracture ( P = 0.000) in the low BMD group compared with the control group.

CONCLUSIONS

The low BMD group demonstrated an inferior biomechanical outcome to the control group with the transtibial technique. With low BMD, the "killer turn" effect compromises the posterior tibial cortex by enlarging the tunnel inlet.

MRI analysis of tibial PCL attachment in a large population of adult patients: reference data for anatomic PCL reconstruction

Background

Consistent reference data used for anatomic posterior cruciate ligament (PCL) reconstruction is not well defined. Quantitative guidelines defining the location of PCL attachment would aid in performing anatomic PCL reconstruction. The purpose was to characterize anatomic parameters of the PCL tibial attachment based on magnetic resonance imaging (MRI) in a large population of adult knees.

Methods

The PCL tibial attachment site was examined in 736 adult knees with an intact PCL using 3.0-T proton density–weighted sagittal MRI. The outcomes measured were the anterior-posterior diameter (APD) of the tibial plateau; angle between the tibial plateau and the posterior tibial ‘shelf’ (the slope where the PCL tibial attachment site was) (PTS); length of the PTS; proximal, central, and distal PCL attachment positions as well as the width of the PCL attachment site; and vertical dimension of the PCL attachment site inferior from the tibial plateau.

Results

The average APD of the tibia plateau was 33.6 ± 3.5 mm, yielding significant differences between males (35.5 ± 3.0 mm) and females (31.6 ± 2.7 mm), P <.05, and there was a significantly decreasing trend with increasing age in males (P <.05). Mean angle between the tibial plateau and the PTS was 122.4° ± 8.1°, and subgroup analysis showed that the young group had a differently smaller angle (120.9° ± 7.5°) than the middle-aged (123.7° ± 8.2°) and the old (123.4° ± 7.7°) in males population, while there were no significant differences between sexes (P >.05). The proximal, central positions and width of the PCL attachment site were 13.4 ± 3.0 mm, 17.8 ± 3.0 mm and 9.6 ± 2.4 mm along the PTS, with significant differences between males and females (P <.05), and accounted for 60.0 % ± 9.1 %, 80.0 % ± 4.6 % and 43.3 % ± 9.7 % of the PTS respectively, with no significant differences between sexes and among age groups (all P >.05).

Conclusions

This study provides reference data of the tibial PCL attachment based on MRI in the sagittal orientation. In analysis of retrospective data from a large population of adult patients, the quantitative values can be used as references to define the inserted angle and depth of the drill guide, and the exact position and size of the tibial PCL tunnel for performing arthroscopic anatomic PCL reconstruction.

Management of Posterior Cruciate Ligament Injuries: An Evidence-Based Review

Isolated injuries of the posterior cruciate ligament are uncommon, are often caused by a posteriorly directed force to the proximal tibia, and result in abnormal knee kinematics and function. A thorough clinical evaluation, including history, physical examination, and imaging, is required to rule out a concomitant structural knee injury. No clear prognostic factors predict outcomes, and ideal management remains uncertain. Nonsurgical management is advocated for isolated grade I or II posterior cruciate ligament injuries or for grade III injuries in patients with mild symptoms or low activity demands. Surgical management is reserved for high-demand athletes or patients in whom nonsurgical management has been unsuccessful. Although biomechanical studies have identified differences between single-bundle, double-bundle, transtibial, and tibial inlay reconstruction techniques, the optimal surgical technique has not been established. No high-quality evidence is available regarding immobilization, weight-bearing, bracing, or rehabilitation protocols for patients treated either nonsurgically or surgically. Additional long-term clinical studies with homogeneous patient populations are needed to identify the ideal management of these injuries.

The mechanism of "killer turn" causing residual laxity after transtibial posterior cruciate ligament reconstruction

Background

The residual laxity after transtibial posterior cruciate ligament (PCL) reconstruction has been reported by several authors. The sharp angle where the graft exits the tibial tunnel, which is known as "killer turn", is believed to be the main reason. The purpose of this study was to reveal the mechanism of "killer turn" and its effect on both graft and tunnel inlet.

Methods

A total of 60 New Zealand white rabbits were included. All transtibial PCL reconstructions were performed in vitro using Achilles tendon autograft. The cyclic loading tests were conducted when reconstructed knees were subjected to 1500 cycles of tensile force of 50 N with the angle of pull at 45° to the tibial plateau. The tunnel inlet enlargement, graft elongation, stiffness, graft displacement, load to failure, and failure site were all recorded and analysed.

Results

Fifty-eight New Zealand white rabbits were available for biomechanical evaluation. The subjects had significant graft elongation and tunnel enlargement. The graft displacement increased by a mean of 0.92 ± 0.36 mm (16.70%). At the 1500^th cycle, the grafts were significantly elongated by 5.59 ± 4.98%, and the tunnel inlet diameter was also significantly enlarged by 12.08 ± 4.31%. There was a linear correlation between total graft displacement and the two variables (R2 = 0.402, F = 18.515, p < 0.001). The coefficient for tunnel inlet enlargement was 0.419 (p = 0.006), and for graft elongation was 0.583 (p = 0.002). At the load-to-failure test, the failure load was 81.19 ± 20.13 N. Of the 58 grafts, 31 (53.45%) failed at the "killer turn", 13 (22.41%) for the para-tunnel fracture, seven (12.07%) for the graft pull-out, and the remaining seven (12.07%) for the rupture at the mounting site.

Conclusion

The mechanism of "killer turn" compromising posterior stability was that the repetitive friction between graft and tunnel inlet not only attenuated the graft, but also enlarged the tunnel inlet, leading to the displacement of the graft.

Emerging Updates on the Posterior Cruciate Ligament: A Review of the Current Literature

The posterior cruciate ligament (PCL) is recognized as an essential stabilizer of the knee. However, the complexity of the ligament has generated controversy about its definitive role and the recommended treatment after injury. A proper understanding of the functional role of the PCL is necessary to minimize residual instability, osteoarthritic progression, and failure of additional concomitant ligament graft reconstructions or meniscal repairs after treatment. Recent anatomic and biomechanical studies have elucidated the surgically relevant quantitative anatomy and confirmed the codominant role of the anterolateral and posteromedial bundles of the PCL. Although nonoperative treatment has historically been the initial treatment of choice for isolated PCL injury, possibly biased by the historically poorer objective outcomes postoperatively compared with anterior cruciate ligament reconstructions, surgical intervention has been increasingly used for isolated and combined PCL injuries. Recent studies have more clearly elucidated the biomechanical and clinical effects after PCL tears and resultant treatments. This article presents a thorough review of updates on the clinically relevant anatomy, epidemiology, biomechanical function, diagnosis, and current treatments for the PCL, with an emphasis on the emerging clinical and biomechanical evidence regarding each of the treatment choices for PCL reconstruction surgery. It is recommended that future outcomes studies use PCL stress radiographs to determine objective outcomes and that evidence level 1 and 2 studies be performed to assess outcomes between transtibial and tibial inlay reconstructions and also between single- and double-bundle PCL reconstructions.

Anatomical study of the posterior cruciate ligament with the knee flexed at 90°

OBJECTIVE

To study the anatomy of the posterior cruciate ligament (PCL) and define anatomical parameters with the knee flexed at 90°.

METHODS

Eight knees from cadavers were dissected in order to make measurements from the center of the anterolateral band to the roof (AL1), from the center of the anterolateral band to the anterior cartilage (AL2), from the center of the posteromedial band to the roof (PM1), from the center of the posteromedial band to the anterior cartilage (PM2), from the center of the tibial insertion to the medial region of the tibia (TIM), from the center of the tibial insertion to the lateral region of the tibia (TIL), from the center of the medial insertion to the medial meniscus (IMM) and the width of the origin of the PCL (WO). To obtain the results from each anatomical structure, the means and standard deviations of the measurements were calculated.

RESULTS

The measurements in millimeters that were found were AL1, 6.2; AL2, 4.9; PM1, 11.7; PM2, 5.5; TIM, 32.5; TIL, 40.6; IMM, 9.4; and WO, 32.5.

CONCLUSIONS

The PCL has an extensive origin. The center of the anterolateral band is 6 mm from the roof and 5 mm from the anterior cartilage of the knee. The tibial insertion is slightly medial and 10 mm distal to the posterior cornu of the medial meniscus.

Displaced avulsion fractures of the posterior cruciate ligament: Treated by stellate steel plate fixation

BACKGROUND

The open reduction with internal fixation is an effective approach for treatment of avulsion fracture of posterior cruciate ligament. The previously used internal fixation materials including hollow screws, absorbable screw, tension bands and sutures have great defects such as insufficient fixation strength, susceptibility to re-fracture, etc. Stellate steel plate is novel material for internal fixation which has unique gear-like structure design. We used stellate steel plate for treatment of displaced avulsion fractures of posterior cruciate ligament in this study.

MATERIALS AND METHODS

14 patients (9 men, 5 women; aged, 19-35 years; mean age, 28 years) with displaced avulsion fractures of the tibial insertion of the posterior cruciate ligament were retrospectively analyzed between June 2009 and June 2011. The mean duration from injury to the operation was 8.3 days (range 6-15 days). All the patients were treated with open reduction and internal fixation of a stellate steel plate (DePuy, Raynham, MA 02767, USA). The Lysholm-Tegner knee function score criteria were used to analyze results.

RESULTS

The mean followup was 24.6 months (range 18-32 months). After 6 months, all the fractures healed and knee joint activity was normal, with no knee stiffness or instability. The Lysholm-Tegner scores were 97.1 ± 1.7 points at the final followup.

CONCLUSION

Owing to its unique gear structure, the stellate steel plate design can effectively fix an avulsion fracture block and it is a simple operation with short postoperative rehabilitation time and firm fixation.

Comparison of single-bundle and double-bundle isolated posterior cruciate ligament reconstruction with allograft: a prospective, randomized study

PURPOSE

The purpose of this study was to evaluate whether posterior cruciate ligament reconstruction with the double-bundle (DB) technique improved stability of the knee compared with the single-bundle (SB) technique.

METHODS

This prospective study included 50 patients who were randomized to undergo posterior cruciate ligament reconstruction by use of tibialis anterior grafts with either the SB technique (25 patients) or DB technique (25 patients). The group assignment was concealed before allocation with the use of sealed envelopes. Posterior stability was evaluated with the KT-1000 arthrometer (MEDmetric, San Diego, CA), and clinical outcomes were assessed with the Lysholm score, Tegner activity score, and International Knee Documentation Committee score (both objective and subjective).

RESULTS

There were 22 patients in the SB group and 24 patients in the DB group with a minimum follow-up period of 2 years. No differences were found between the 2 groups regarding patient demographic data and the duration from injury to operation (P > .05). The Lysholm score was 88.0 ± 4.2 (range, 83 to 93) in the SB group and 89.8 ± 3.8 (range, 86 to 95) in the DB group, and there was no significant difference between the 2 groups (P = .447). The Tegner activity score improved significantly to 6.2 ± 0.9 (range, 5 to 8) in the SB group and 6.8 ± 1.2 (range, 5 to 9) in the DB group. The side-to-side difference in posterior translation decreased to 4.1 ± 1.3 mm (range, 5.5 to 2.5 mm) in the SB group and 2.2 ± 1.3 mm (range, 4.5 to 2.0 mm) in the DB group, and there was a significant difference between the 2 groups (P < .05). According to the International Knee Documentation Committee (both objective and subjective), the DB group had a better grade distribution (P < .05) and had a statistically higher grade (71.6 ± 6.7; range, 63 to 80) than the SB group (65.5 ± 7.8; range, 56 to 75) (P < .05).

CONCLUSIONS

Although both techniques resulted in similar patient satisfaction as measured by outcome assessment, the DB procedure significantly improved knee stability.

LEVEL OF EVIDENCE

Level II, lesser-quality randomized controlled trial.