Posterior Cruciate Ligament Injuries of the Knee at the National Football League Combine: An Imaging and Epidemiology Study

All-Inside PCL Reconstruction, Double Bundle, With Internal Brace Augmentation

PCL reconstructive techniques are constantly evolving, and further clinical studies are needed to definitively understand the potential benefits of internal brace augmentation and anatomic double-bundle PCL reconstruction. This Technical Note reports an arthroscopic all-inside anatomic double-bundle PCL reconstruction with internal brace augmentation that is effective and reproducible.

Clinical, patient-reported, radiographic and magnetic resonance imaging findings 11 years after acute posterior cruciate ligament injury treated non-surgically

BACKGROUND

Long-term consequences of posterior cruciate ligament (PCL) injury such as persistent posterior tibial translation and risk of osteoarthritis development are unclear. Additionally, little data is available describing the natural history of structural morphology of the ruptured PCL. The purpose of the study was to determine the long-term outcome after non-operatively treated PCL injury.

METHODS

Over 6-years, all acute knee injuries were documented by subacute MRI (median 8 days [5-15, 25th - 75th percentile] from injury to MRI). Twenty-six patients with acute PCL injury were identified of whom 18 (69%) participated in the long-term follow-up after 11 years. Follow-up included radiographic posterior tibial translation (RPTT) determined using the Puddu axial radiograph. weight-bearing knee radiographs, MRI and KOOS (Knee injury and Osteoarthritis Outcome Score).

RESULTS

On subacute MRI, 11 knees displayed total and 7 partial ruptures. At 11 (SD 1.9) years, the median RPTT was 3.7 mm (1.5-6.3, 25th - 75th percentile). Seven knees displayed radiographic osteoarthritis approximating Kellgren-Lawrence grade ≥ 2. All follow-up MRIs displayed continuity of the PCL. Patients with more severe RPTT (> 3.7 mm), had worse scores in the KOOS subscales for symptoms (mean difference 14.5, 95% CI 7-22), sport/recreation (30, 95% CI 0-65) and quality of life (25, 95% CI 13-57) than those with less severe RPTT (≤ 3.7 mm). This was also the case for the KOOS₄ (22, 95% CI 9-34).

CONCLUSION

Acute PCL injuries treated non-surgically display a high degree of PCL continuity on MR images 11 years after injury. However, there is a large variation of posterior tibial translation with higher values being associated with poorer patient-reported outcomes.

Decreased lateral posterior tibial slope and medial tibial depth are underlying anatomic risk factors for posterior cruciate ligament injury: a case-control study

Objectives

To research whether medial PTS, lateral PTS and MTD were different between the PCL injury group and the PCL intact group.

Design

Retrospective case–control study, level of evidence III.

Methods

Fifty patients with PCL rupture from 2015 to 2020 in our hospital, and 50 patients matched by age and sex with intact PCL were enrolled in our study. The intraclass correlation coefficient (ICC) was used to assess the reliability of each parameter. The independent t-test was conducted to identify the differences in tibial morphometric characteristics between the PCL-injured and PCL-intact individuals, including the posterior tibial slope (PTS), meniscal slope (MS), medial tibial depth (MTD). A binary logistic regression model was established to evaluate the roles of those anatomic parameters of interest play in PCL injuries.

Results

The interobserver reliability of each parameter showed excellent agreement. Significant differences in the medial (P = .023) and lateral (P = .009) PTS were found between the PCL-injured group (3.68 ± 2.70 and 4.55 ± 3.19, respectively) and the controls (5.00 ± 2.73 and 6.39 ± 3.29, respectively). And the MTD was 1.98 ± 0.64 mm in the PCL-injured group and 2.37 ± 0.55 mm in the control group (P = 0.007). Binary logistic regression analysis showed that smaller lateral PTS and MTD were directly associated with PCL injury, with an OR of 1.17 and OR of 3.14, respectively. The medial PTS was independent to PCL injures.

Conclusion

Decreased lateral PTS and MTD were underlying anatomic risk factors for PCL injury.

Patients with isolated posterior cruciate ligament rupture had a higher posterior intercondylar eminence

Background

To evaluate the anatomic geometry of the posterior intercondylar eminence and its association with PCL injury risk.

Methods

Patients who underwent primary PCL reconstruction from 2015 to 2018 were retrospectively analyzed. The control group included inpatients diagnosed with ACL rupture because of a sports-related accident during the same period, matched by age, gender, height, weight, and side of injury. Measurements of the height of the apex of the posterior intercondylar eminence (HPIE), the slope length (SLPIE) and the slope angle (SAPIE) of the posterior intercondylar eminence were performed using conventional MRI scans assessed by 2 blinded, independent raters. Intraclass correlation coefficients (ICCs) was used to evaluate the consistency of measurement results. Independent sample t tests, Chi-square tests, and logistic analyses were used to compare the two group, with P < 0.05 considered statistically significant.

Results

Fifty-five patients with PCL rupture met the inclusion criteria and 55 PCL-intact matched controls were included. There were no significant differences between the groups in gender (P = 1.000), limb side (P = 0.848), age (P = 0.291), BMI (P = 0.444) or height (P = 0.290). Inter-observer reproducibility was excellent agreement in HPIE, SLPIE and SAPIE of case and control groups (ICC: HPIE = 0.81, SLPIE = 0.77, SAPIE = 0.85). Patients with PCL rupture had significantly greater HPIE, SAPIE (both P < 0.001), and SLPIE (P < 0.05) than PCL-intact patients. The multivariable analysis showed that HPIE (OR, 1.62 [95% CI, 1.24–2.11], P < 0.001) and SAPIE (OR, 1.17 [95% CI, 1.05–1.31], P < 0.001) were independent factors associated with PCL rupture.

Conclusion

Through this retrospective observational study, we found that patients with PCL rupture may have a higher posterior intercondylar eminence compared to PCL-intact patients.

Level of evidence

III.

Epidemiology of Posterior Cruciate Ligament Reconstructions in Italy: A 15-Year Study

Background: The posterior cruciate ligament (PCL) is an essential element in knee stability. PCL reconstructions represent an under-investigated topic in the literature due to the rarity of this type of knee injury. This study aims to investigate the incidence of PCL reconstructive surgeries in Italy, following their trend during a 15-year period. Methods: The National Hospital Discharge records (SDO) collected by the Italian Ministry of Health between January 2001 and October 2015 were analyzed. The database reports anonymous data comprising patients’ ages, genders, International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes for diagnosis and intervention, census regions, regions of hospitalization, lengths of hospitalization and types of reimbursement. Results: The overall incidence of PCL reconstructions in the Italian population during the study period was 0.46 surgeries per 100,000 inhabitants/year, ranging from 0.32 to 0.54. The median patient’s age was 30 years old, and the male:female ratio was 5.3. PCL lesions were isolated in 39.7% of patients, while anterior cruciate ligament injuries were the most frequently associated lesions (31.1%). Conclusions: The incidence of PCL reconstruction in Italy was low and stable during the study period. Young men are the category at the highest risk for these procedures. Given the paucity of epidemiological data on PCL reconstructions, this data may represent a reference for the current and foreseeable needs in PCL surgeries for countries sharing similar cultural context.

Biomechanical evaluation of PCL reconstruction with suture augmentation

PURPOSE

The purpose of this study was to compare kinematics and patellofemoral contact pressures of all inside and transtibial single bundle PCL reconstructions and determine if suture augmentation further improves the biomechanics of either technique.

METHODS

Cadaveric knees were tested with a posterior drawer force, and varus, valgus, internal and external moments at 30, 60, 90, and 120° of flexion. Displacement, rotation, and patellofemoral contact pressures were compared between: Intact, PCL-deficient, All-Inside PCL reconstruction with (AI-SA) and without (AI) suture augmentation, and transtibial PCL reconstruction with (TT-SA) and without (TT) suture augmentation.

RESULTS

Sectioning the PCL increased posterior tibial translation (PTT) from intact at 60° to 120° of flexion, p < 0.001. AI PCL reconstruction improved stability from the deficient-state but had greater PTT than intact at 90° of flexion, p < 0.05. Adding suture augmentation to the AI reconstruction further reduced PTT to levels that were not statistically different from intact at all flexion angles. TT reconstructed knees had greater PTT than intact knees at 60, 90, and 120° of flexion, p < 0.01. Adding suture augmentation (TT-SA) improved posterior stability to PTT levels that were not statistically different from intact knees at 30, 60, and 120° of flexion. Patellofemoral pressures were highest in PCL-deficient knees at increased angles of flexion and were reduced after reconstruction, but this was not significant.

CONCLUSION

In this time-zero study, both the all-inside and transtibial single bundle PCL reconstructions effectively reduce posterior translation from the deficient-PCL state. In addition, suture augmentation of both techniques provided further anterior-posterior stability.

Athletes With Musculoskeletal Injuries Identified at the NFL Scouting Combine and Prediction of Outcomes in the NFL: A Systematic Review

Background:

Prior to the annual National Football League (NFL) Draft, the top college football prospects are evaluated by medical personnel from each team at the NFL Scouting Combine. On the basis of these evaluations, each athlete is assigned an orthopaedic grade from the medical staff of each club, which aims to predict the impact of an athlete’s injury history on his ability to participate in the NFL.

Purpose:

(1) To identify clinical predictors of signs, symptoms, and subsequent professional participation associated with football-related injuries identified at the NFL Combine and (2) to assess the methodological quality of the evidence currently published.

Study Design:

Systematic review; Level of evidence, 3.

Methods:

A systematic review was conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. We reviewed all studies that examined musculoskeletal injuries identified among athletes at the NFL Combine and associated outcomes. Data on signs, symptoms, and subsequent NFL participation were collected, and the methodological quality of the studies was assessed.

Results:

Overall, 32 studies, including 30 injury-specific studies, met the inclusion criteria. Twenty studies analyzed data collected at the NFL Combine from 2009 and later. When compared with matched controls, athletes with a history of a cervical or lumbar spine injury, rotator cuff repair, superior labrum anterior-posterior repair, anterior cruciate ligament reconstruction, full-thickness chondral lesions of the knee, or Lisfranc injury played in significantly fewer games early in their NFL careers. Additionally, athletes with a history of a cervical or lumbar spine injury, rotator cuff repair, and navicular injury had decreased career lengths versus controls. Defensive players and linemen were found to have decreased participation in the NFL for several injuries, including prior meniscectomy, anterior cruciate ligament reconstruction, and shoulder instability. Career length follow-up, measures of athletic participation, and matching criteria were highly variable among studies.

Conclusion:

For medical professionals caring for professional football athletes, this information can help guide orthopaedic grading of prospects at the NFL Combine and counseling of athletes on the potential impact of prior injuries on their professional careers. For future studies, improvements in study methodology will provide greater insight into the efficacy of current treatments and areas that require further understanding.

Single Versus Double-Bundle PCL Reconstruction: Scientific Rationale and Clinical Evidence

PURPOSE OF REVIEW

The goal of this paper is to review the biomechanical and clinical rationale for single-bundle versus double-bundle posterior cruciate ligament (PCL) reconstruction. The primary question is whether there has been demonstrated any clear biomechanical or clinical superiority of a double-bundle reconstruction over a single-bundle reconstruction.

RECENT FINDINGS

There is some recent evidence demonstrating biomechanical superiority of double-bundle versus single-bundle reconstruction; however, this is not definitive. Clinical superiority has not been clearly demonstrated as of yet. The primary question which served as the basis of this review remains unanswered. There is recent biomechanical data to suggest a potential benefit of double-bundle versus single-bundle reconstruction, but not all studies are in agreement. Furthermore, the possible biomechanical advantages have not yet been borne out in clinical studies. At this point, we cannot clearly recommend one technique versus another and the decision should be left to the treating surgeon.