Epidemiology of Tibial Fractures in Professional American Football Athletes From 2013 to 2019

Background: Lower extremity injuries occur with high frequency in National Football League (NFL) athletes and cause high burden to players and teams. Tibial fractures are among the most severe lower extremity injuries sustained in athletes and are associated with prolonged time loss from sport. Purpose: To determine the number of tibial fractures in NFL athletes from the 2013 to 2019 NFL seasons and describe athlete demographics, fracture characteristics, and details of injury onset. Study Design: Case series; Level of evidence, 4. Methods: A retrospective review of the NFL injury database was performed to identify all NFL athletes sustaining tibial fractures over the 2013 to 2019 NFL seasons. Athlete characteristics, injury characteristics, days missed, and treatment (operative vs nonoperative) were examined. Descriptive statistics were used to calculate means, standard deviations, ranges, and percentages. Results: A total of 64 tibial fractures were identified in 60 athletes, resulting in a median loss of 74 days. Defensive secondary athletes had the highest number of injuries (n = 10; 16%), followed by running backs (n = 9; 14%), while 61% of these injuries occurred during NFL regular-season games, primarily between weeks 13 and 17. The most commonly reported activity during injury was athletes being tackled, with a direct impact to the tibia being the most common mechanism of injury. Lateral tibial plateau fractures were the most frequently reported, while distal tibial fractures resulted in the greatest number of days lost. The median time lost for injuries requiring surgery was 232 days compared with 56 days for injuries treated using conservative management. Conclusion: The highest proportion of tibial fractures were injuries to defensive secondary athletes and athletes being tackled while sustaining a direct impact to the leg, primarily to the lateral tibial plateau. Tibial fracture injuries were commonly sustained during NFL regular-season games, primarily during the final 4 weeks of the NFL regular season. Further investigations examining performance and career longevity in athletes sustaining tibial fractures are warranted to help improve the health and safety of NFL athletes.

Reliability of Plain Radiographs Versus Magnetic Resonance Imaging to Measure Tibial Slope in Sports Medicine Patients: Can They Be Used Interchangeably?

Background: The slope of the tibial plateau has been proposed as a reason for failure of anterior cruciate ligament reconstruction. Purpose: To evaluate the interobserver reliability of measurements of tibial slope on radiographs versus magnetic resonance imaging (MRI) scans and to assess whether the modalities can be used interchangeably for this purpose. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: This retrospective study included 81 patients aged 18 to 30 years who were evaluated in a sports medicine setting for knee pain and who had lateral knee radiographs as well as knee MRI scans on file. Medial and lateral tibial plateau slope measurements were made by 3 blinded reviewers from the radiographs and MRI scans using graphic overlay software. The paired t test was used to compare measurements of the medial tibial plateau slope (MTPS) and lateral tibial plateau slope (LTPS) from radiographs and MRI scans. Intraclass correlation coefficients (ICCs) were calculated to determine intra- and interobserver reliability of measurements within each imaging modality, and Pearson correlation coefficients were calculated to determine the relationship between measurements on radiographs versus MRI scans. Results: Imaging from 81 patients were included. The average MTPS was significantly larger on radiographs compared with MRI scans (8.7° ± 3.6° vs 3.7° ± 3.4°; P < .001), and the average LTPS was also significantly larger on radiographs compared with MRI scans (7.9° ± 3.4° vs 5.7° ± 3.7°; P < .001). ICC values indicated good to excellent intraobserver agreement for all imaging modalities (ICC, 0.81-0.97; P ≤ .009). The ICCs for interobserver reliability of MTPS and LTPS measurements were 0.92 and 0.85 for radiographs, 0.87 and 0.83 for MRI based off the subchondral bone, and 0.86 and 0.71 for MRI based off the cartilage, respectively ( P < .001). Medium correlation was noted between radiographic and MRI measurements; Pearson correlation coefficients for radiographic versus subchondral MRI measurements were 0.30 and 0.37 for MTPS and LTPS, respectively. Conclusion: The average MTPS and LTPS were significantly larger on radiographs compared with MRI scans. Although tibial slope measurements using radiography and those using MRI are reliable between individuals, the measurements from radiographs and MRI scans cannot be used interchangeably, and caution should be used when interpreting and comparing studies using measurements of the tibial slope.

Lateral Extra-articular Tenodesis Alters Lateral Compartment Contact Mechanics under Simulated Pivoting Maneuvers: An In Vitro Study

Background: There is concern that utilization of lateral extra-articular tenodesis (LET) in conjunction with anterior cruciate ligament (ACL) reconstruction (ACLR) may disturb lateral compartment contact mechanics and contribute to joint degeneration. Hypothesis: ACLR augmented with LET will alter lateral compartment contact mechanics in response to simulated pivoting maneuvers. Study Design: Controlled laboratory study. Methods: Loads simulating a pivot shift were applied to 7 cadaveric knees (4 male; mean age, 39 ± 12 years; range, 28-54 years) using a robotic manipulator. Each knee was tested with the ACL intact, sectioned, reconstructed (via patellar tendon autograft), and, finally, after augmenting ACLR with LET (using a modified Lemaire technique) in the presence of a sectioned anterolateral ligament and Kaplan fibers. Lateral compartment contact mechanics were measured using a contact stress transducer. Outcome measures were anteroposterior location of the center of contact stress (CCS), contact force from anterior to posterior, and peak and mean contact stress. Results: On average, augmenting ACLR with LET shifted the lateral compartment CCS anteriorly compared with the intact knee and compared with ACLR in isolation by a maximum of 5.4 ± 2.3 mm ( P < .001) and 6.0 ± 2.6 mm ( P < .001), respectively. ACLR augmented with LET also increased contact force anteriorly on the lateral tibial plateau compared with the intact knee and compared with isolated ACLR by a maximum of 12 ± 6 N ( P = .001) and 17 ± 10 N ( P = .002), respectively. Compared with ACLR in isolation, ACLR augmented with LET increased peak and mean lateral compartment contact stress by 0.7 ± 0.5 MPa ( P = .005) and by 0.17 ± 0.12 ( P = .006), respectively, at 15° of flexion. Conclusion: Under simulated pivoting loads, adding LET to ACLR anteriorized the CCS on the lateral tibial plateau, thereby increasing contact force anteriorly. Compared with ACLR in isolation, ACLR augmented with LET increased peak and mean lateral compartment contact stress at 15° of flexion. Clinical Relevance: The clinical and biological effect of increased anterior loading of the lateral compartment after LET merits further investigation. The ability of LET to anteriorize contact stress on the lateral compartment may be useful in knees with passive anterior subluxation of the lateral tibia.

Anatomical basis of the support of fibula to tibial plateau and its clinical significance

Background The fibula is only indirectly involved in the composition of the human knee joint and has therefore been neglected in the research on knee osteoarthritis. Nonuniform settlement of the proximal tibia plateau is clinically defined as when the height of the medial tibial plateau is lower than that of the lateral side in medial compartment knee osteoarthritis (KOA). The non-uniform settlement of the proximal tibia plateau may be caused by fibular support on the lateral side. Orthopedic surgeons practice partial fibulectomy based on the clinical manifestation of nonuniform settlement, and this technique has been shown to reduce pain and improve function in patients with medial compartment KOA. However, this hypothesis of the mechanism of nonuniform settlement lacks an anatomical basis. Methods The P45 polyester plastination technique was used to prepare sections of the proximal tibiofibular joint to investigate the distribution of the bone trabeculae in the region of the lateral tibial plateau. Results There was uneven distribution of trabeculae in the lateral condyle of the tibia and the head and neck of the fibula. The fibula and the posterolateral cortex of the shaft of the tibia united to form an arch beam via the tibiofibular joint. Many thick, dense trabeculae were present in a longitudinal direction above the tibiofibular arch. Conclusions The fibula supports the lateral tibial plateau, and the trabeculae were concentrated above the tibiofibular arch.

Comparison of outcomes of ORIF versus bidirectional tractor and arthroscopically assisted CRIF in the treatment of lateral tibial plateau fractures: a retrospective cohort study

Background Lateral tibial plateau fractures (TPFs) are often treated with conventional open reduction and internal fixation (ORIF) through standard anterolateral sub-meniscal arthrotomy. There has been increasing support for “bidirectional rapid redactor” device-assisted closed reduction and internal fixation (CRIF) for treating TPFs. The aim of the present study is to compare the clinical and radiological outcomes between CRIF and ORIF procedures. Methods We performed a retrospective cohort study of 55 lateral TPF patients (Schatzker types I–III) who accepted surgical treatment at our trauma level 1 center between January 2016 and January 2018. They were divided into the CRIF group (32 patients) and the ORIF group (23 patients) based upon the different surgical protocols. The patients’ clinical outcome analysis was evaluated by using the Knee Society Score (KSS) and Rasmussen’s clinical score. For radiological assessment, changes in tibial plateau width (TPW), articular depression depth (ADD), medial proximal tibial angle (MPTA), and posterior tibial slope angle (PTSA) were evaluated using radiographs and computed tomography (CT) scan. Results The CRIF group had a mean follow-up of 28.9 months, and the ORIF group had a mean follow-up of 30.7 months (p>0.05). Furthermore, there was no statistically significant difference in terms of age, gender, injury mechanism, follow-up time, time interval from injury to surgery, and Schatzker classification in the two groups. With respect to the clinical outcomes including the KSS score and Rasmussen’s clinical score, there was also no significant difference (p>0.05). Nevertheless, the CRIF group had lower intra-operative blood loss, shorter hospitalization days, and better range of movement of the knee joint than the ORIF group (p<0.05). Furthermore, CRIF had better radiological results when compared to the ORIF group using Rasmussen’s radiological score (p<0.05), although no significant difference was observed in TPW, ADD, MPTA, and PTSA between the two groups (p>0.05). Conclusion The present study showed that CRIF could achieve comparable clinical outcomes and better radiological results for treating lateral TPFs as compared with conventional ORIF.