The amount of displacement can determine non-operative treatment in posterior cruciate ligament avulsion fracture

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.

[Treatment of Injuries to the Posterior Cruciate Ligament]

Compared to the anterior cruciate ligament injury, the rupture of the posterior cruciate Ligament (PCL) is the rarer condition. A high healing potential is attributed to the PCL in the literature, which is why conservative therapy is also considered important in addition to surgical treatment 1. Posterior cruciate ligament rupture is often associated with concomitant injuries. Among other things, up to 70% of cases are associated with accompanying injuries to the posterolateral corner 2. The detection of concomitant injuries has a significant influence on the outcome, as isolated surgical PCL stabilization does not lead to satisfactory results in these cases.

Biomechanical study of posterior cruciate ligament tibial arrest avulsion fracture fixation with triple tibial channel net sutures

To investigate the biomechanical properties of posterior cruciate ligament avulsion fractures of the tibia fixed using four different methods, including triple tibial channel net suture fixation. In 40 porcine knees, a standardized bony avulsion of the posterior cruciate ligament was generated. Double tibial bone channel suture fixation was performed in group A, double-head hollow compression screw fixation was performed in group B, triple tibial bone channel net suture fixation was performed in group C, and cortical suspension EndoButton fixation was performed in group D. The constructs were cyclically loaded 500 times (10 to 100 N) to measure the initial displacement and stiffness values. Subsequently, loading to failure was performed, and the yield load and peak load were measured. The results were analysed by one-way ANOVA, with significance set at P < 0.05. The initial displacement in group D (1.00 ± 0.20 mm) was lower than that in group C (1.46 ± 0.33 mm, P = 0.000), group B (1.91 ± 1.71 mm, P = 0.000) and group A (3.91 ± 0.79 mm, P = 0.000), but there was no significant difference between groups B and C (P = 0.055). The initial stiffness in group A (50.59 ± 6.89 N/mm) was lower than that in group C (67.21 ± 12.80 N/mm, P = 0.001), group D (71.18 ± 9.20 N/mm, P = 0.000) and group B (78.67 ± 5.91 N/mm, P = 0.000). However, there was no significant difference between groups B and D or between groups C and D (P = 0.111 and P = 0.391). The yield load in group A (554.86 ± 71.43 N) was lower than that in group C (767.00 ± 34.53 N, P = 0.000), group D (777.62 ± 73.03 N, P = 0.000) and group B (837.50 ± 55.73 N, P = 0.000). There was no significant difference between groups C and D (P = 0.729). The peak load in group A (667.38 ± 61.54 N) was lower than that in group C (842.00 ± 26.20 N, P = 0.000), group D (867.63 ± 63.42 N, P = 0.000) and group B (901.25 ± 54.38 N, P = 0.000). There was no significant difference between groups C and D (P = 0.346). Different failure modes were found among the four groups. The triple tibial bone channel suture fixation group showed better initial stability and fixation strength, which was comparable to that in the cortical suspension EndoButton fixation group and double-head hollow compression screw fixation group and significantly stronger than that in the double tibial bone channel suture fixation group. This study analysed the dynamic and static indexes of posterior cruciate ligament tibial avulsion fractures fixed by four different fixation methods under cyclic loading tests and single failure loading tests, providing a theoretical basis for clinical treatment.

Systematic Review and Meta-analysis of Clinical Outcomes After Management of Posterior Cruciate Ligament Tibial Avulsion Fractures

Background

There is no consensus regarding the management of posterior cruciate ligament (PCL) avulsion fractures and the expected outcomes after treatment.

Purpose

To systematically review clinical outcomes and complications after management of tibial-sided avulsion fractures of the PCL.

Study Design

Systematic review; Level of evidence, 4.

Methods

A literature search of Scopus, PubMed, Medline, and the Cochrane Central Register for Controlled Trials was performed in accordance with the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Included were studies with evidence levels 1 to 4 that reported clinical outcomes after treatment of PCL tibial-sided avulsion fractures in humans. The quality of the included studies was performed using the Methodological Index for Non-Randomized Studies (MINORS) criteria. A meta-analysis was performed for patient-reported outcome measures using random-effects modeling with 95% CIs.

Results

A total of 58 studies published between 1999 and 2022 were identified. The mean MINORS score was 9.90 ± 4.12, indicating overall low-quality evidence with high risk of bias. The studies comprised 1440 patients (mean age, 32.59 ± 5.69 years; 75.2% males) with a mean follow-up of 26.9 ± 19.6 months (range, 5.3-126 months). Most patients were treated with open surgery (63.6%), followed by arthroscopic surgery (29.7%) and nonoperative treatment (6.7%). All patients reported significant posttreatment improvement in both subjective and objective outcomes (P < .05 for all). Arthroscopic surgery was associated with lower postoperative posterior tibial translation compared with open surgery (range, 0.6-3.2 vs 1.7-3.1 mm), greater preoperative to postoperative improvement in Lysholm score (54.6 vs 48.8; P < .0001), higher postoperative Tegner score (6.64 ± 1.03 vs 6.14 ± 2.29; P = .0448), and a higher rate of return to sport (100% vs 89.5%; P = .009). Nonoperative management was associated with a significantly lower fracture union rate (87% vs 99.1%; P < .0001) and greater postoperative side-to-side posterior translation (4.9 ± 4.3 mm) when compared with operative management.

Conclusion

Although nonoperative and surgical management of PCL tibial avulsion fractures resulted in high rates of fracture union and improvement in functional outcome scores and a low incidence of complications, nonoperative treatment yielded a high side-to-side posterior displacement (>4 mm) with a lower rate of fracture union compared to surgical treatment.

Effect of Posterior Tibial Slopes on Graft Survival Rates at 10 Years After Primary Single-Bundle Posterior Cruciate Ligament Reconstruction

BACKGROUND

Recent biomechanical studies have reported that stress on the posterior cruciate ligament (PCL) graft increases as the posterior tibial slope (PTS) decreases (flattened) in knees with single-bundle (SB) and double-bundle PCL reconstruction. Clinical studies of SB PCL reconstruction have shown that a flattened PTS is associated with a lesser reduction in posterior tibial translation. There is no long-term study on the clinical outcomes and graft survival rates of SB PCL reconstruction based on the medial and lateral PTSs measured on magnetic resonance imaging.

HYPOTHESIS

Flattened medial and lateral PTSs are associated with poor clinical outcomes and graft survival rates at a minimum 10-year follow-up after SB PCL reconstruction.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

In this cohort study, we retrospectively reviewed 46 patients (mean age, 28.8 ± 9.9 years) who underwent primary SB PCL reconstruction between 2000 and 2009. They were followed up for a minimum of 10 years. The medial and lateral PTSs were measured on preoperative magnetic resonance imaging. As a previous study reported that a steeper medial or lateral PTS showed a higher risk of anterior tibial translation at thresholds of 5.6° and 3.8°, respectively, the patients were divided into 2 groups based on the cutoff values of both the medial (≤5.6° vs >5.6°) and lateral (≤3.8° vs >3.8°) PTSs. Clinical scores (International Knee Documentation Committee subjective score, Lysholm score, and Tegner activity score), radiological outcomes (side-to-side difference [SSD] on stress radiography and osteoarthritis progression), and graft survival rates were compared between the groups at the last follow-up.

RESULTS

All clinical scores and the progression of osteoarthritis demonstrated no significant difference between the 2 subgroups of both the medial and lateral PTS groups. The mean SSD on stress radiography after SB PCL reconstruction was significantly greater in patients with a medial PTS ≤5.6° than in patients with a medial PTS >5.6° (8.4 ± 3.9 vs 5.1 ± 2.9 mm, respectively; P = .030), while the lateral PTS subgroups after SB PCL reconstruction demonstrated no significant difference. The minimum 10-year graft survival rate was significantly lower in patients with a medial PTS ≤5.6° (68.4% vs 92.6%, respectively; P = .029) and a lateral PTS ≤3.8° (50.0% vs 91.7%, respectively; P = .001).

CONCLUSION

A flattened medial PTS (≤5.6°) was associated with an increased SSD on stress radiography, and both flattened medial (≤5.6°) and lateral (≤3.8°) PTSs resulted in lower graft survival rates at a minimum 10-year follow-up after primary SB PCL reconstruction.

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.

Morphological Risk Factors for Posterior Cruciate Ligament Tear and Tibial Avulsion Injuries of the Tibial Plateau and Femoral Condyle

BACKGROUND

Identification of morphological risk factors associated with the knee that threaten ligaments is important for understanding injury mechanisms and prevention. However, the morphological risk factors for posterior cruciate ligament (PCL) lesions are not clearly understood.

PURPOSE

To investigate whether the medial tibial depth (MTD), medial and lateral posterior tibial slope, asymmetry of the medial and lateral slopes, radius of the sagittal plane medial femoral condyle, coronal tibial slope, and notch width index (NWI) were risk factors for PCL intrasubstance tearing (PCLIT) and tibial avulsion fractures (PCLAF).

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Between January 2015 and March 2022, 82 patients with isolated PCLIT, 68 patients with isolated PCLAF, and 82 controls without any ligamentous or meniscal pathologic findings as determined via physical examination and magnetic resonance imaging were included. Values were compared among the 3 groups. Logistic regression analysis was performed to confirm the risk factors. Receiver operating characteristic curves were defined for the morphological indicators and combination of risk factors.

RESULTS

Logistic regression analysis revealed (1) MTD, lateral minus medial posterior tibial slope, radius of the posterior circle of the medial femoral condyle, and NWI as significant independent predictors for PCLIT and (2) MTD and NWI for PCLAF. The areas under the curve combining the 4 indicators for PCLIT and noncontact PCLIT were 0.79 (95% CI, 0.72-0.86) and 0.90 (95% CI, 0.85-0.96), respectively. The area under the curve for the combination of MTD and NWI for PCLAF was 0.78 (95% CI, 0.70-0.86).

CONCLUSION

Decreased MTD and NWI were associated with an increased incidence of PCLIT and PCLAF. Increased asymmetry of the medial and lateral slopes and the radius of the posterior circle of the medial femoral condyle were associated with the presence of PCLIT. In addition, the model of a combination of risk factors showed good predictive ability for noncontact PCLIT. These findings may aid clinicians in identifying patients at risk for PCL lesions. Further studies are warranted for identifying the effect of these factors on biomechanical mechanisms.

Homemade pin-hook for surgical treatment of posterior cruciate ligament avulsion fractures

Background

How to treat the posterior cruciate ligament (PCL) tibial insertion small and comminuted avulsion fracture is still challenging. Our study evaluated the clinical and radiological outcomes after ORIF of PCL tibial insertion avulsion fractures through the inverted L-shaped postero-medial approach using a homemade pin-hook.

Methods

Between January 2009 and December 2020, twenty-four patients with isolated PCL tibial insertion bony avulsion were enrolled. There were 16 males and 8 females. The age range was 18-48 (32.5 ± 9.3) years. The time from injury to surgery was 1-10 (4.4 ± 2.8) days. There were 11 cases in the left knee and 13 cases in the right knee. The patients received anticoagulant therapy to prevent thrombosis. Preoperative standard X-ray, computerized tomography (CT) and magnetic resonance imaging (MRI) were performed. According to the Meyers-McKeever classification, there were 8 cases of type II and 16 cases of type III.

Results

The operation time was 60-120 (89.6 ± 19.8) min. Postoperative follow-up ranged from 3 to 18 months. The average follow-up was 11.4 ± 4.3 months. In all patients, one or two homemade pin-hooks were used to fix different sizes of fracture segments. X-ray or CT scans taken after surgery revealed fracture union. The fractures healed in 9-16 (11.8 ± 1.7) weeks. At the last follow-up, the patients were able to fully straighten. The ROM (132.6° ± 3.9°), the Tegner-Lysholm score (96.2 ± 2.3) and the IKDC scores (95.5 ± 1.6) were all significantly improved compared with the preoperative values (77.5° ± 13.1°, 46.8 ± 8.9, 36.2 ± 7.9). The posterior drawer test was negative. The gastrocnemius muscle strength did not diminish. No internal fixation migration was observed during the follow-up. No neurovascular bundle- or hardware-related complications were reported.

Conclusions

The inverted L-shaped postero-medial approach with homemade pin-hook fixation for the treatment of PCL avulsion fractures produces acceptable clinical and radiological results. Moreover, the homemade pin-hook made of K-wires is affordable and reduces patient costs. It is a practical application and worth recommending, especially for community hospitals.

Minimally invasive versus traditional inverted "L" approach for posterior cruciate ligament avulsion fractures: a retrospective study

Purpose

To evaluate the clinical efficacy of a minimally invasive arthroscopic approach and to compare it with the traditional inverted "L" approach for the treatment of posterior cruciate ligament (PCL) avulsion fractures.

Methods

From January 2016 to January 2020, the clinical data from patients with PCL avulsion fracture of the tibial insertion were analyzed retrospectively. They were divided into two groups based on surgical approaches: minimally invasive approach group (n = 15) and traditional inverted "L" group (n = 15 cases). The operation time, incision length, intraoperative blood loss, hospitalization time and complications were all recorded and compared between the two groups. The fracture healing time, knee range of motion (ROM), and residual relaxation degree were compared between the two groups after regular follow-up. The International Knee Documentation Committee (IKDC) and Lysholm scores were used to assess knee joint function.

Results

There were no significant differences between the two groups in terms of gender, age, side, body mass index, cause of injury, Meyers McKeever classification and time from injury to operation (P > 0.05). The incision length and intraoperative bleeding in the minimally invasive group were significantly lower (P < 0.05) than those in the traditional group. There were no significant differences between the two groups in terms of operative time, fracture healing time, or residual relaxation (P > 0.05). The Lachman test and posterior drawer test were both negative, and there were no postoperative complications. The VAS pain score within 2 weeks and ROM within 4 weeks in the minimally invasive group were significantly better (P < 0.05) than those in the traditional inverted "L" approach group. The knee joint stability of both groups was good 12 months after surgery, and there were no significant differences in IKDC score, Lysholm score and ROM (P > 0.05) between the two groups.

Conclusion

The minimally invasive approaches for the treatment of PCL avulsion fractures provide adequate exposure without the surgical complications associated with traditional open surgical approaches. The procedure is safe, fast and minimally invasive, and does not need a long learning curve.

Clinical outcomes of rectangular tunnel technique in posterior cruciate ligament reconstruction were comparable to the results of conventional round tunnel technique

PURPOSE

To compare clinical outcomes between the conventional round and rectangular tunnel techniques in single-bundle posterior cruciate ligament (PCL) reconstruction.

METHODS

Twenty-seven and 108 patients who underwent PCL reconstructions using a rectangular dilator (Group 1) and rounded tunnel reamer (Group 2), respectively, were included. The exclusion criteria were having a concomitant fracture, osteotomy, subtotal or total meniscectomy, and no remnant PCL tissue. A 4:1 propensity score matching was performed. The knee laxity on stress radiography, International Knee Documentation Committee Subjective Knee Evaluation score, Tegner activity score and Orthopädische Arbeitsgruppe Knie score were evaluated.

RESULTS

No significant differences were found between the groups in terms of clinical scores. (n.s.) The mean posterior translations were also not significantly different between the Group 1 and 2 (3.6 ± 2.8 and 3.8. ± 3.1 mm, respectively; n.s.). However, 3 patients (11.1%) in Group 1 and 15 patients (13.8%) in Group 2 showed posterior translation of > 5 mm. The combined posterolateral corner sling technique was performed for 27 patients (100%) in Group 1 and for 96 patients (88.9%) in Group 2. We found no significant difference in rotational stability at the final follow-up. One patient was found to have a femoral condyle fracture during rectangular femoral tunnel establishment, which was healed after screw fixation, without laxity, during follow-up. The intra- and inter-observer reliabilities of the radiological measurements ranged from 0.81 to 0.89.

CONCLUSION

Arthroscopic anatomical remnant-preserving PCL reconstruction using a rectangular dilator showed satisfactory clinical results and stability as compared with PCL reconstruction using a conventional rounded reamer. Rectangular tunnel technique in PCL reconstruction could be a good treatment option with theoretical advantage to be anatomic.

LEVEL OF EVIDENCE

Level IV.

Arthroscopic Suture-to-Loop Fixation of Posterior Cruciate Ligament Tibial Avulsion Fracture

Avulsion fracture of the tibial insertion of the posterior cruciate ligament (PCL) receives constant concern. Arthroscopic procedures have long been attempted because of their minimally invasive nature, and various related techniques have been reported. However, the best arthroscopic method is still being pursued. In this article, we introduce an arthroscopic suture ligation and backup adjustable-loop fixation technique for PCL tibial avulsion fracture. The critical points of this technique are proper ligation of the PCL, proper location of the 2 tibial tunnels to create pulleys for posterior-inferior reduction of the bone fragment, and additional backup suture loop fixation. Our experience indicates that this technique is efficient and relatively simple. We consider that the introduction of this technique will provide a reasonable choice in the treatment of PCL tibial avulsion fracture.