Measurement of Medial Tibial Eminence Dimensions for the Clinical Evaluation of ACL-Injured Knees: A Comparison between CT and MRI

Anterior cruciate ligament (ACL) injuries commonly lead to translational and rotational tibiofemoral instability. The morphology of the medial tibial eminence (MTE) has received increased attention regarding its role in tibiofemoral stability in ACL-injured knees. Therefore, quantification of MTE dimensions on clinical imaging may help clinicians predict knee stability after ACL injury. Although magnetic resonance imaging (MRI) is routinely obtained in patients with ACL injuries, whether the dimensions of the MTE can be accurate quantified on MRI is unknown. The purpose of this study was to assess the degree of correlation between measurements of MTE height and width on computed tomography (CT) versus MRI. An institutional picture archiving and communication system imaging database was used to identify patients aged between 15 and 60 years who received concurrent MRI and CT of the same knee within a 1-year interval. Knees with significant arthrosis, deformity, intraarticular fracture, or hardware-related artifact that obscured visualization of the MTE were excluded. Mean differences and interstudy agreement between CT and MRI MTE measurements were compared using concordance correlation coefficient (r c) and Bland–Altman analysis. A total of 41 knees in 38 patients (mean age, 37 years; 82% male) were analyzed. Interrater reliability for CT and MRI measurements was high (intraclass correlation coefficient = 0.740–0.954). On coronal CT and MRI, mean MTE height measurements were 10.4 ± 1.9 and 10.4 ± 1.8 mm, respectively; mean MTE width measurements were 14.6 ± 3.6 and 14.2 ± 3.0 mm, respectively. On sagittal CT and MRI, mean MTE height measurements were 11.6 ± 1.7 and 11.7 ± 1.7 mm, respectively; mean MTE width measurements were 36.5 ± 4.8 and 36.2 ± 5.0 mm, respectively. Good agreement was observed between CT and MRI measurements of MTE height and width on coronal and sagittal planes (r c = 0.947–0.969). Measurements of MTE height and width were similar on MRI relative to CT on both coronal and sagittal planes. MRI may be suitable for characterizing the dimensions of the MTE when clinically evaluating patients with ACL injuries, potentially allowing for individualized patient care.

Clinical Effect of Day-case Arthroscopic Surgery of Tibial Eminence Fracture using the Button Plates for Treatment in Adults

Background: The aim of this paper is to evaluate the early clinical efficacy and complications of arthroscopic treatment of tibial eminence fracture (TEF) with button plates.Methods: Retrospective analysis of patients with TEF fracture treated by arthroscopic surgery was performed. Clinical subjective evaluation included the International Knee Documentation Committee (IKDC) scores, Lysholm knee score, and visual analog scale (VAS). The knee joint scores were evaluated according to the Lysholm score. Clinical objective assessment included the Lachman test, anterior drawer test (ADT), IKDC, and the range of motion. The patient's quality of life was measured using a life summary table. Assessment of fracture healing and internal fixation was performed on lateral X-rays of the knee joint. The patients’ satisfaction was measured and evaluated at the last follow-up in accordance with Marsh criteria. RESULTS: There were 22 patients (22 knees) with a mean age of 33.64 ± 8.60 years. The mean follow-up was 28.36 ± 2.79 months. The difference in Lachman test and ADT before and after the operation was statistically significant. According to the IKDC classification, there were 11 cases with type A, 9 cases with type B, and 2 cases with type C. According to the intra-articular button position classification, the rate of ideal position was 100%. The satisfaction rate was 81.8%.CONCLUSIONS: Day surgery using double-button plates to treat TEF can achieve anatomical reduction, power and stability, and good clinical efficacy.

Fraturas da Eminência da Tíbia na Infância – Descrição de Abordagem Artroscópica e Resultados Funcionais

Pediatric fractures of the tibial eminence are relatively rare, equivalent to the anterior cruciate ligament rupture in the adult. Severely displaced tibial eminence fractures should be treated surgically. Arthroscopy is preferred as it allows for accurate diagnosis and treatment of associated lesions and reduction and fixation of all types of tibial spine fractures while reducing the morbidity associated with open techniques. We report the clinical and radiological results of two cases with displaced tibial eminence fractures, submitted to surgical treatment and the arthroscopic technique of internal fixation with absorbable suture. After a follow-up of 18 months both patients had great improvement. Radiographic exams confirm complete fracture healing at 6 weeks of follow-up. The International Knee Documentation Committee subjective score were excellent (96 and 98 points) and the range of motion of the injured knees were also similar to the no-injured knees. This arthroscopic technique is simple, reproducible and very useful in dealing with these fractures, allowing to obtain excellent functional results.

Effect of Skeletal Maturity on Fixation Techniques for Tibial Eminence Fractures

Background: Several fixation methods have been reported for the operative treatment of tibial eminence fractures. Previous biomechanical studies have demonstrated that suture fixation may be a stronger construct; however, the maturity status of these specimens was not scrutinized. Purpose: To examine if suture fixation remains a biomechanically superior fixation method to screw fixation in both skeletally mature and immature specimens. Study Design: Controlled laboratory study. Methods: Sixteen total matched porcine (Yorkshire) knees (8 skeletally immature knees and 8 skeletally mature knees) were procured, and a standardized tibial eminence fracture was created. In each age-matched group of knees, 4 knees underwent randomization to fixation with 2 screws while 4 knees were randomized to fixation using a dual-suture technique. Once fixation was complete, the specimens underwent cyclic loading (200 cycles) in the anteroposterior plane of the tibia and load-to-failure testing, both with the knee positioned at 30° of flexion. Relevant measurements were recorded, and data were analyzed. Results: Among mature specimens, load to failure was 1.9 times higher in the suture fixation group compared with the screw fixation group (1318.84 ± 305.55 vs 711.66 ± 279.95 N, respectively; P = .03). The load to failure was not significantly different between the groups in immature specimens (suture: 470.00 ± 161.91 N vs screw: 348.79 ± 102.46; P = .08). Conclusion: These findings suggest that suture fixation may represent a better construct choice for fixation of tibial eminence fractures in the skeletally mature population. However, in the skeletally immature population, fixation with screws or suture may be equivalent. Displacement after cyclic loading did not appear to differ by fixation method, nor did stiffness. Clinical Relevance: A stronger fixation construct may be beneficial and allow for earlier range of motion to help potentially decrease postoperative stiffness. Clinical studies are warranted to see if these results may be replicated in humans.

ARE SEGOND FRACTURES OF THE TIBIA PATHOGNOMONIC FOR ACL TEARS IN THE PEDIATRIC AND ADOLESCENT POPULATION?

Background: Segond fractures (avulsion fractures of the proximal lateral tibia) are considered to be pathognomonic for anterior cruciate ligament (ACL) tears in adult patients. Purpose: To describe the largest case series of pediatric Segond fractures and associated intra-articular injuries of the knee to determine if these fractures are pathognomonic for ACL tears in young patients. Methods: IRB-approved retrospective study of patients under 20 years who presented with Segond fracture to a tertiary children’s hospital between 2009-2019. Demographics, clinical data, imaging features, associated injuries, and treatment information were collected. Results: 55 patients (46 males, 9 females) with mean age 15.2 years (11.8-19.1) with Segond fractures of the proximal tibia on radiology imaging were identified (Fig.1.2). Diagnosis of associated injuries was established based on clinical examination, radiology report and findings during arthroscopy. Average Segond fracture size was 2.7 x 9.5mm as measured on standard knee radiographs. Magnetic resonance imaging (MRI) was obtained in 49/55(89%) patients. Associated injuries included anterior cruciate ligament (ACL) tears (39 patients, 70.9%), tibial eminence fractures (9, 16.4%), and all other injuries (7, 12.7%) (Table 1.1). Among Segond fractures found with ACL tears, 12 (30.8%) were contact injuries, 30 (76.9%) were sports injuries. In associated tibial spine fractures, 7 (78%) injuries were contact in nature and were sports related. When age was compared between the patient group with ACL tears (mean 15.7 years) to the ones with tibial spine fractures ( mean 13.9 years), there was a statistically significant difference(p=0.007). 12/55 (21.8%) had associated articular cartilaginous injuries, 3 of which required surgical intervention. 37/55 (67.3%) patients had meniscal injury. 3 (5.5%) patients suffered multi-ligament injuries. Overall, 87.2% of the patients required surgical management for associated intra-articular injuries of the knee. Conclusion: The Segond (tibial avulsion) fracture is associated with intra-articular injuries the pediatric population, most commonly ACL tears and meniscus tears. However, the largest case series in the pediatric population suggests that they are not pathognomonic for ACL tears as a notable proportion of patients, especially the ones who are younger in age, have tibial eminence fractures or no ACL tears. [Table: see text][Figure: see text]

ANTERIOR CRUCIATE LIGAMENT TEAR FOLLOWING SURGICAL TREATMENT OF PEDIATRIC TIBIAL EMINENCE FRACTURE IN A MULTICENTER COHORT

Background: While operative treatment of displaced pediatric tibial eminence fractures has generally been shown to be safe, post-operative complications including arthrofibrosis, infection, fixation failure, and postoperative ipsilateral ACL injuries remain prevalent. The purpose of this study was to describe the prevalence of and risk factors for post-operative ACL tears in a cohort of patients surgically treated for tibial eminence fracture. Methods: We performed a retrospective review of children undergoing treatment of a tibial eminence fracture at 10 tertiary children’s hospitals.. The primary outcome was subsequent ACL rupture. Patients with 2 year follow up data and those that had met the primary outcome within the 2 year period, were analyzed for demographics, risk factors and survival analyses Results: 385 pediatric patients were reviewed. Overall, 46 patients had either 2 year follow up data or met the primary outcome measure of an ACL tear prior to the 2 year mark. Mean age was 11.2 years old (SD 2.8), and the median follow time was 36.4 months (SD 17.7 months) There was a 21.7% incidence of subsequent ACL tear in the cohort analyzed. Subsequent ACL tears occurred at a median of 10.2 months (SD 19.5 months) postoperatively. There was a statistically significant association with higher Myers & McKeever grade tibial spine fractures (Type III and IV) and subsequent ACL rupture ( p=0.006). Subsequent ACL tears occurred in patients who were older when they had their original tibial eminence fracture, 13.4 years old versus 11.3 years old ( p=0.035). There was no statistically significant relationship between ipsilateral ACL tear and body mass index, operative time, fixation method used, postoperative weight bearing status, type of postoperative immobilization, contact versus non-contact injury mechanism, type of post-operative physical therapy protocol based on chi-squared or t-test ( p>0.05). Conclusion: Subsequent ipsilateral ACL tears following operatively treated pediatric tibial eminence fractures in a large multicenter cohort occurred at a rate of 21.7%. They were associated with completely displaced (Type III or IV) tibial eminence fractures, and older patients. Clinicians should therefore continue to follow patients for at least 2 years after treatment of pediatric tibial eminence fractures in order to track this potential complication. [Table: see text]

A New Arthroscopic Tightrope Suture-Button Fixation Procedure for Tibial Eminence Avulsion Fracture

This case-series outcome study presents a new arthroscopic technique for tibial eminence avulsion fracture (TEAF) with double-tunnel using two tightrope suture buttons. From May 2017 to July 2020, we performed a new arthroscopic technique for TEAF with double tunnels, using two tightrope suture buttons on 13 patients. Clinical assessments included anterior drawer, Lachman, and pivot shift tests, the International Knee Documentation Committee (IKDC), Lysholm knee scores, visual analog scale (VAS) scores, and range of motion (ROM). An independent observer noted conditions before surgery and during the last follow-up. The patients had an average follow-up of 26.2 months, ranging from 15 to 37 months. During the last postsurgical follow-up, the anterior drawer, Lachman, and pivot shift tests were negative in all the cases. According to the IKDC, Lysholm, and VAS final scores, all patients presented a significant knee function improvement at last follow-ups compared with preoperatively. The study shows that satisfactory results about an anatomic reduction of the fragment, knee stability, function, and strength can be achieved with the new arthroscopic technique for TEAF with double tunnels using two tightrope suture buttons. This study is a therapeutic case series and its level of evidence is IV.

Reliable ligamentous stability and high return-to-sport rates after arthroscopic reduction and internal fixation of tibial eminence fractures

Purpose To investigate functional and clinical outcomes, and physical activity after arthroscopic suture fixation of tibial eminence fractures with regard to postoperative stability, range of motion (ROM), complications, and return to sports. Methods Patients undergoing arthroscopic reduction and internal fixation (ARIF) of tibial eminence fractures using a suture fixation technique were included. Outcome was evaluated retrospectively after a minimum follow-up of 24 months using KT-1000 arthrometer measurements, clinical examination, outcome scores (Lysholm score, Tegner Activity Scale), and a questionnaire about sport activities. Results A total of 23 patients (44% male, 57% female) with a mean age of 25 ± 15 years were included. Mean follow-up was 57 ± 25 months. KT-1000 arthrometer measurements of anterior tibial translation revealed a mean side-to-side difference of 0.9 ± 1.0 mm. Clinical examination showed 100% normal or nearly normal anterior translation of the tibia. Two patients (9%) received an ACL reconstruction due to traumatic ACL re-instability and were, therefore, considered as failures. An extension deficit concerning hyperextension occurred in 29% of patients postoperatively. Further postoperative complications occurred in 14% of patients and included postoperative stiffness with ROM limitations and secondary dislocation of a fragment. Mean postoperative Lysholm score was 89 ± 14. Comparing pre- and postoperative values, no significant change of the Tegner Activity Scale was observed. All patients (failures excluded) returned to high impact sports activities after ARIF. Conclusion Excellent reliable ligamentous stability and high rates of return to high impact sports can be expected after ARIF using a suture fixation technique for type II–IV tibial eminence fractures. Complications, such as limitations in ROM, commonly occur in up to 30% after ARIF. Therefore, regular follow-up examinations remain important in this usually young patient cohort. Level of Evidence Level IV.