Impacts of Segond Fractures on Anterior Cruciate Ligament Reconstruction Outcomes.

INTRODUCTION: Segond fractures, characterized by avulsion injuries at the lateral tibial condyle's anterolateral structure (ALS) attachment, often coincide with anterior cruciate ligament (ACL) injuries, potentially leading to knee instability. However, the influence of Segond fractures on knee stability after ACL reconstruction remains uncertain. Despite documented ALS reconstructions, there is a lack of consensus regarding the assessment of ALS failure and the criteria for surgical interventions. This study aimed to determine if Segond fracture presence impacts ACL reconstruction outcomes, utilizing patient-reported subjective assessments and healthcare providers' objective evaluations. MATERIALS AND METHODS: This retrospective study encompassed 639 patients (328 males, 311 females; mean age 26.9 years) who underwent ACL reconstruction, with a follow-up of at least one year. Subjects were divided into two groups: Segond fractures diagnosed through radiographic findings (Group S+, n = 17) and no Segond fractures (Group S-, n = 622). Clinical evaluation included the 36-item Short Form Survey (SF-36), Lysholm score, visual analog scale (VAS) for knee pain, knee injury and osteoarthritis outcome score (KOOS), and knee instability assessment via Telos SE (Telos Japan, Tokyo, Japan). Statistical comparisons were performed between the two groups. RESULTS: At the final follow-up, all SF-36 subscales improved in all eight subscales compared to before surgery, reaching national standard scores; no significant inter-group differences were evident. Lysholm scores were 93.0 ± 12.1 (Group S+) and 91.7 ± 10.9 (Group S-) (P = 0.62), VAS for knee pain was 10.0 ± 18.0 (Group S+) and 11.9 ± 16.9 (Group S-) (P = 0.62), total KOOS was 89.0 ± 17.4 (Group S+) and 90.7 ± 9.9 (Group S-) (P = 0.39), and anterior tibial translation differences were 2.8 ± 3.0 mm (Group S+) and 2.7 ± 2.9 mm (Group S-) (P = 0.73). All these values represent postoperative measurements. No significant discrepancies existed between groups across evaluation methods. CONCLUSIONS: This study's results suggest that Segond fractures have minimal impact on clinical ACL reconstruction outcomes, as assessed through both patient-reported subjective evaluations and objective healthcare provider evaluations. Segond fractures' significance in postoperative outcomes questions the necessity of ALS reconstruction.

Segond fracture: an indicator for increased risk of lateral meniscus injury in patients with acute anterior cruciate ligament ruptures.

PURPOSE: The purpose of this study was to investigate the incidence and anatomic distribution of meniscus injury in patients who have sustained acute ACL injuries with and without concomitant Segond fracture. We hypothesized that patients who have sustained a torn ACL with a concomitant Segond fracture would have a higher incidence of lateral meniscal injuries than patients with an isolated ACL injury. METHODS: Patients who underwent ACL reconstruction from 2012 to 2022 were retrospectively reviewed. Segond fractures were identified on knee radiographs. Inclusion criteria were age 18-40, injury during sports activity, and reconstruction within 90 days of injury. Sports activity, anatomic location of meniscus injury, and meniscus treatment were documented. Multivariable regression was used to identify predictors of meniscus injury/treatment. RESULTS: There were 25 of 603 (4.1%) patients who had an ACL tear with concomitant Segond fracture. The incidence of lateral meniscus injury in the Segond group (72%) was significantly higher than in the non-Segond cohort (49%; p = 0.024). A significantly smaller proportion of medial meniscus injuries among patients with Segond fractures were repaired (23.1%) compared to the non-Segond group (54.2%; p = 0.043). Multivariate analysis found patients with Segond fractures to have increased odds of lateral meniscus injury (OR 2.68; [1.09, 6.60], p = 0.032) and were less likely to have medial meniscus injuries repaired (OR 0.35; [0.15, 0.81], p = 0.014). Additionally, males had increased odds of lateral meniscus injury (OR 1.54; [1.08 - 2.91], p = 0.017), which were more likely to require repair (OR 1.48; [1.02, 2.14], p = 0.038). CONCLUSIONS: Among acute ACL injuries, the incidence of lateral meniscus injury is greater among patients with Segond fractures. Patients with Segond fracture were less likely to undergo repair of medial meniscal injuries.

Lateral meniscal injury without medial meniscal injury indicates the existence of the Segond fracture in ACL-deficient knees.

Background/Objective: The purpose of this study was to find factors indicating the occurrence of the Segond fracture, a specific type of anterolateral ligament injury. Methods: From January 2015 to December 2017, we retrospectively reviewed the medical records of patients diagnosed with acute anterior cruciate ligament (ACL) injury who underwent reconstruction within 90 days of injury. Diagnosis of the Segond fracture was determined either by magnetic resonance imaging or plain radiographs. Factors examined were: age at surgery, sex, body mass index (kg/m2), status of menisci, and activities led to ACL injury. After univariate screening, multivariate logistic regression analyses were performed. Patients were divided into four groups based on the presence of lateral meniscal (LM) and/or medial meniscal (MM) injuries and compared with respect to the occurrence of Segond fractures. Results: A total of 375 patients were included (163 males, 212 females), with mean age 25.8 years old. Among them, 22 of 375 (5.9 %) had a Segond fracture. We identified injured lateral menisci (adjusted odds ratio (aOR), 3.029; 95 % Confidence Interval (CI), 1.206-7.609; P = 0.018), intact medial menisci (aOR, 0.229; 95 % CI, 0.065-0.810; P = 0.022), and higher body mass index (aOR, 1.102; 95 % CI, 1.008-1.205; P = 0.034) as factors indicative of the occurrence of Segond fracture. LM injury without MM injury suggested the existence of a Segond fracture. Conclusion: LM injury without a MM injury indicated the occurrence of a Segond fracture. Higher body mass index also increased the risk for Segond fracture occurrence.

Localizing the position of the Segond fracture bed under CT measurements to determine the functional tibial insertion of an anterolateral ligament.

Background: Many studies have confirmed the existence of ligament structures in the anterolateral region of the knee that maintain rotational stability of the knee joint, namely, the anterolateral ligament (ALL). Most scholars believe that knee joint reconstruction should be considered during revision surgery and a high level of pivot displacement test (stage 2 or 3). During ALL reconstruction, the choice of ligament reconstruction sites affects the success rate and prognosis of the operation. Therefore, the choice of ligament reconstruction sites is particularly important. There is little research on the lateral ALL tibia insertion point, and most clinicians use the midpoint Gerdy's tubercle and fibular head as insertion points. However, the reconstruction effect is not ideal. Objective: This study aims to measure the position of the Segond fracture bed on CT images to determine the ALL position of the tibia. Method: To determine the position of the Segond fracture bone bed, the CT AM Volume Share 2 system was used to manually measure the position of bone fragments in 23 Segond fracture patients. Using the highest point of Gerdy's tubercle in the CT axial slices and the outermost point of the fibular head in the CT axial slices as reference points, the direction and angle of the CT slices were adjusted to ensure that the highest point of the Gerdy tubercle, the outermost point of the fibular head, and the center of Segond fracture bed were in the same sagittal slice. A CT sagittal slice measures the vertical distance from the center of the Segond fracture bed to the Gerdy-fibular line segment (G-F line segment), which is the line connecting the highest point of the segment to the outermost point of the fibula. The distance from the vertical point at the center of the Segond fracture bed of the G-F line to the highest point of the Gerdy tubercle was measured. All measurements were performed using the same measurement standard and were expressed as a percentage of the length of the G-F line. The measured results were statistically analyzed using SPSS 25.0 descriptive statistical research methods. Results: The average length of the G-F segment measured on CT images was 39.6 ± 2.0 mm, and the average vertical length from the center of the Segond fracture bed to the G-F segment was 13.1 ± 1.1 mm, accounting for 33.2% ± 2.1% of the length of the G-F segment. The length from the vertical point of the fracture bed on the G-F line segment to the highest point of the Gerdy tubercle was 14.7 ± 1.3 mm, accounting for 37.1% ± 2.9% of the length of the G-F segment. Conclusion: Through the study of the CT measurement of the Segond fracture location, we obtained the location of the functional tibial insertion of ALL, which is different from the anatomical insertion of ALL and is more inclined to the Gerdy tubercle and above, which has reference value for the treatment of recovering the function of anterolateral ligament after reconstruction.

Clinical Outcomes After Anterior Cruciate Ligament Reconstruction in Patients With a Concomitant Segond Fracture: A Systematic Review.

BACKGROUND: The Segond fracture can be observed in patients with an anterior cruciate ligament (ACL) tear. It is unclear whether the Segond fracture affects clinical outcomes after ACL reconstruction. PURPOSE: To investigate whether the presence of a concomitant Segond fracture affects clinical outcomes after ACL reconstruction and to compare clinical outcomes when a Segond fracture is repaired surgically or left unrepaired. STUDY DESIGN: Systematic review; Level of evidence, 4. METHODS: Three databases (PubMed, Embase, Cochrane Library) were searched in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines on July 27, 2020. Relevant studies regarding ACL injury with concomitant Segond fracture treated by primary ACL reconstruction were screened in duplicate. Data regarding patient characteristics and clinical outcomes were extracted. Descriptive data are presented, and a random-effects model was used to pool amenable data. RESULTS: A total of 5 studies examining 2418 patients (987 female; 40.8%), mean age 25.4 years, were included in this study. There were 304 patients with a Segond fracture (mean age, 28.1 years; 35.9% female) and 2114 patients without a Segond fracture (mean age, 25.1 years; 41.5% female). Four studies directly compared outcomes between patients with an unrepaired Segond fracture and no Segond fracture. One study reported 12 patients who underwent ACL reconstruction and repair of a Segond fracture. Among 4 studies, 11 of 292 (3.8%) graft failures/revision surgeries were reported in the groups that had Segond fracture, whereas 145 of 2114 (6.9%) graft failures/revision surgeries were reported in groups that did not have Segond fracture. No significant difference was observed in the risk of graft failure between the 2 groups, with a pooled risk ratio of 0.59 (95% CI, 0.32-1.07; P = .08; I2 = 0%). No clinically significant differences were observed with regard to International Knee Document Committee score, Lysholm score, Tegner activity scale, and postoperative knee laxity between the group with Segond fracture and those without. CONCLUSION: An unrepaired Segond fracture does not appear to have any significant negative effect on postoperative stability or risk of graft failure or revision surgery after ACL reconstruction. Future prospective studies may be warranted to confirm the finding that patients with combined ACL injury and Segond fracture may have outcomes comparable with those of ACL-injured patients without a Segond fracture when isolated ACL reconstruction is performed.

Ipsilateral ACL injured patients with Segond fractures demonstrate increased posterior tibial slope.

BACKGROUND: The anterolateral complex has been demonstrated to assist with rotational stability and prevention of anterior tibial translation during the pivot shift. In this study the Segond fracture is used as a surrogate for an anterolateral complex injury to determine if there is an association between Segond fracture and increased posterior tibial slope. METHODS: Patients' charts and radiographs were analyzed retrospectively for the presence of Segond fractures on injury radiographs. These patients, the Segond cohort, were then age and gender matched to a control cohort. Demographic as well MRI measurements of medial and lateral posterior tibial slope and lateral-to-medial slope asymmetry were collected for each cohort. Secondary outcome of anterior cruciate ligament reconstruction failure data was also collected. RESULTS: The Segond group demonstrated a statistically significantly greater lateral posterior tibial slope (8.42° versus 6.55°, P = 0.003) as well as medial posterior tibial slope (6.57° versus 5.34° degrees, P = 0.045). There was no significant differences between lateral-to-medial asymmetry (2.18°versus 1.83°, P = 0.246). CONCLUSION: Patients with Segond fractures at the time of anterior cruciate ligament injury have increased medial and lateral posterior tibial slope. This may relate to increased rotational and translational instability associated with anterolateral complex injuries. Surgeons treating these patient may use this information to counsel their patients on the risks of associated pathology at the time of arthroscopy such as lateral meniscal posterior root tears.

Prevalence of Segond fractures associated with anterior cruciate ligament injuries and their influence on knee joint stability; A case-control study.

BACKGROUND: The purpose of this study was to determine the prevalence of Segond fractures and to compare knee stability between patients undergoing primary anterior cruciate ligament (ACL) reconstruction with and without Segond fractures pre- and postoperatively. METHODS: A total of 712 patients who underwent primary ACL reconstruction between 2014 and 2019. Exclusion criteria included patients with multi-ligament knee injuries, skeletally immature patients, osteoarthritis in the knee, combined surgery of high tibial osteotomy, lack of data, and loss to follow-up for at least 2 years. Segond fractures were confirmed using plain radiography, computed tomography (CT), and magnetic resonance imaging (MRI). Patients with Segond fractures were classified into Group S and without Segond fractures into Group N. Pre- and postoperative Lachman grades, pivot-shift grades, and assessment of side-to-side differences in anterior stability were evaluated. RESULTS: Five hundred and forty patients included in this study. There were 22 patients with Segond fractures. Of these, all 22 cases (4.1%) were identified on CT, but only 20 cases (3.7%) were identified on MRI and 18 cases (3.3%) on plain radiographs. There was no significant difference in preoperative Lachman grade or pivot-shift grade between Groups S and N (p = 0.662, p = 0.677, respectively). There was no significant difference in postoperative Lachman grade or pivot-shift grade between Groups S and N (p = 0.685, p = 0.390, respectively). There were no significant differences in preoperative (p = 0.398) or postoperative (p = 0.546) side-to-side differences of anterior stability between Groups S and N. CONCLUSIONS: Segond fractures were confirmed in 4.1% of the cases on CT scans among patients undergoing primary ACL reconstruction. Segond fractures did not affect preoperative or 2-year follow-up evaluations of knee stability. From these results, we concluded that Segond fractures did not affect the clinical outcomes of the primary ACL reconstruction and that it may not be necessary to treat Segond fractures.

Deep learning detection of subtle fractures using staged algorithms to mimic radiologist search pattern.

OBJECTIVE: To develop and evaluate a two-stage deep convolutional neural network system that mimics a radiologist's search pattern for detecting two small fractures: triquetral avulsion fractures and Segond fractures. MATERIALS AND METHODS: We obtained 231 lateral wrist radiographs and 173 anteroposterior knee radiographs from the Stanford MURA and LERA datasets and the public domain to train and validate a two-stage deep convolutional neural network system: (1) object detectors that crop the dorsal triquetrum or lateral tibial condyle, trained on control images, followed by (2) classifiers for triquetral and Segond fractures, trained on a 1:1 case:control split. A second set of classifiers was trained on uncropped images for comparison. External test sets of 50 lateral wrist radiographs and 24 anteroposterior knee radiographs were used to evaluate generalizability. Gradient-class activation mapping was used to inspect image regions of greater importance in deciding the final classification. RESULTS: The object detectors accurately cropped the regions of interest in all validation and test images. The two-stage system achieved cross-validated area under the receiver operating characteristic curve values of 0.959 and 0.989 on triquetral and Segond fractures, compared with 0.860 (p = 0.0086) and 0.909 (p = 0.0074), respectively, for a one-stage classifier. Two-stage cross-validation accuracies were 90.8% and 92.5% for triquetral and Segond fractures, respectively. CONCLUSION: A two-stage pipeline increases accuracy in the detection of subtle fractures on radiographs compared with a one-stage classifier and generalized well to external test data. Focusing attention on specific image regions appears to improve detection of subtle findings that may otherwise be missed.

Anterolateral complex injuries occur in the majority of 'isolated' anterior cruciate ligament ruptures.

PURPOSE: The anterolateral soft tissue envelope of the knee is frequently injured at the time of ACL rupture. This study aims to investigate the MRI injury patterns to the Anterolateral complex and their associations in patients with acute 'isolated ligament' ACL ruptures. METHODS: Professional athletes who underwent ACL reconstruction for complete ACL rupture between 2015 and 2019 were included in this study. Patients' characteristics and intraoperative findings were retrieved from clinical and surgical documentation. Preoperative MRIs were evaluated and the injuries to respective structures of the Anterolateral complex and their associations were recorded. RESULTS: Anterolateral complex injuries were noted in 63% of cases. The majority of injuries were to Kaplan Fibre (39% isolated injury and 19% combined with Anterolateral ligament injury). There was a very low incidence of isolated Anterolateral ligament injuries (2%). Kaplan Fibre injuries are associated with the presence of lateral femoral condyle bone oedema, and injuries to the superficial MCL, deep MCL, and ramp lesions. High grade pivot shift test was not associated with the presence of Kaplan Fibre or Anterolateral ligament injuries. Patients with an intact Anterolateral complex sustained injury to other knee structures (13% to medial ligament complex, 14% to medial meniscus, and 16% to lateral meniscus). CONCLUSION: There is a high incidence of concomitant Anterolateral complex injuries in combination with ACL ruptures, with Kaplan Fibre (and therefore the deep capsulo-osseous layer of the iliotibial band) being the most commonly injured structure. Anterolateral ligament injuries occur much less frequently. These findings reinforce the importance of considering the presence of, and if necessary, treating injuries to structures other than the ACL, as a truly isolated ACL injury is rare.

The relationship between a Segond fracture and meniscus injury in patients with anterior cruciate ligament tears.

BACKGROUND: Segond fracture may be identified when an anterior cruciate ligament (ACL) tear is diagnosed, and it has historically been considered a sign of significant knee trauma indicating intra-articular injury. There are few studies on the correlation between a Segond fracture and meniscus injury. The purpose of this study was to evaluate the relationship between a Segond fracture and meniscus injury in patients with ACL tears. METHODS: A retrospective review of all patients undergoing acute ACL reconstruction (less than 1 month from the time of injury) between 2013 and 2020 was performed. The absence or presence of a Segond fracture was confirmed using preoperative radiographs. Demographic data (age, sex and body mass index), injury variables (time from injury and mechanism of injury) and arthroscopic features (meniscal or chondral injury) were analysed to investigate the relationship between a Segond fracture and meniscus injury. RESULTS: A total of 427 patients were included in the study. The incidence of Segond fractures was 12.4%. Among the patients with a Segond fracture, 15 patients were injured playing soccer (28.3%), 11 patients were injured playing basketball (20.8%), eight patients sustained the injury during racquet sports (15.1%), five patients (9.4%) were injured during less popular sports (such as skiing, ice-skating and boxing), and 14 patients (26.4%) were injured by contact mode of injury. A Segond fracture was a significant risk factor for lateral meniscus tears in patients with ACL tears (adjusted odds ratio, 1.938; 95% confidence interval, 1.078-3.481; P = 0.027). CONCLUSION: The incidence of Segond fractures in patients with acute ACL tears was higher than that reported in previous studies. A Segond fracture could increase the risk of a lateral meniscus tear in patients with an ACL tear.

Unusual combination of posterior cruciate ligament tibial avulsion fracture and Segond fracture: A case report.

INTRODUCTION AND IMPORTANCE: Posterior cruciate ligament (PCL) avulsion fracture is an uncommon entity, but it poses significant morbidity to patient's knee and activities. A combination of PCL avulsion fracture with Segond fracture is rare and has not been described much before in known literature. In this case report, we present a rare case of a combination of these two injuries. CASE PRESENTATION: A 16-year-old cyclist who sustained left knee injury after a high-velocity fall while cycling. He fell with his anteromedial side of his left knee hitting the ground in flexion. After the fall, he felt excruciating pain and unable to bear weight. Examination revealed severe joint effusion, tenderness on posterior and lateral side of the left knee, no vascular injury and neurological deficit present. Radiographic examination revealed PCL avulsion fracture and Segond fracture. Five days after the injury, the avulsed PCL fragment and the lateral tibial plateau fragment were reduced and fixed with 3.5 mm cortical screw and washers. On the follow up, the patient stated that there is no pain on weightbearing position and after evaluated with Knee injury and Osteoarthritis Outcome Score (KOOS), the result is 90%. CLINICAL DISCUSSION: Although the combination of PCL avulsion fracture and Segond fracture is rare, this pattern of injury could happen and could be considered when evaluating knee injuries. CONCLUSION: Both fractures need to be addressed and managed adequately to restore knee stability and prevent early joint degeneration.

Lateral collateral ligament and anterolateral ligament of the knee - A morphological analysis with orthopedic significance.

BACKGROUND: The lateral collateral ligament (LCL) is the chief stabilizer of the lateral aspect of the knee to varus forces. Studies have confirmed the function of the anterolateral ligament (ALL), which improves the lateral knee stability by preventing excessive internal tibial rotation. Clinically, a persistent instability following anterior cruciate ligament reconstruction may be due to damage to the anterolateral structures. The finding has created a novel interest in anterolateral extra-articular operations. METHODS: This observational, cross-sectional study involved 42 dissected adult knees. The variations in morphology and morphometry of the LCL were identified and classified. The prevalence and the variabilities in the ALL were also noted. RESULTS: The variations in the shape of the LCL were classified into four types: (1) cord, (2) band, (3) mixed, and (4) inverted Y shaped, with a frequency of 69.04, 26.20, 2.38, and 2.38% of specimens, respectively. The cord type measured 50.4 ± 2.7 mm in length and 5 ± 0.9 mm in width. In comparison, the band type measured 50.1 ± 4.2 mm in length and 9 ± 1.6 mm in width. The ALL was identified in four (9%) of the specimens with a mean length of 35 ± 0.9 mm. Two types of ALL were observed, membranous wideband and distinct cord-like ALL. CONCLUSION: The anatomy of the lateral structures of the knee is inconsistent. The study has attempted to classify the different shapes of the LCL along with the frequency and prevalence of the ALL. Orthopedic surgeons and radiologists must note the LCL morphology and prevalence of the ALL due to their clinical implications.

Timing of magnetic resonance imaging affects the accuracy and interobserver agreement of anterolateral ligament tears detection in anterior cruciate ligament deficient knees.

PURPOSE: We aimed to identify the anterolateral ligament (ALL) tears in anterior cruciate ligament (ACL)-deficient knees using standard 1.5-Tesla magnetic resonance imaging (MRI). METHODS: We included all patients who underwent primary ACL reconstruction at our center between 2012 and 2015. Exclusion criteria included patients with multiple ligament injuries, lateral collateral ligament, posterolateral corner, and infections, and patients who underwent MRI more than 2 months after their injury. All patients (n = 148) had ACL tears that were subsequently arthroscopically reconstructed. The magnetic resonance (MR) images of the injured knees performed within 2 months of injury were reviewed by a musculoskeletal radiologist and an orthopedic surgeon. The patients were divided into two groups. The first group of patients had MRI performed within 1 month of injury. The second group of patients had MRI performed 1-2 months after the index injury. Both assessors were blinded and the MR mages were read separately to assess the presence of ALL, presence of a tear and the location of the tear. Based on their readings, interobserver agreement (kappa statistic (K)), sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were compared. RESULTS: The ALL was identified in 100% of the patients. However, there was a discrepancy of up to 15% in the identification of tear of the ALL. In the first group in which MRI scans were performed within 1 month of injury, the ALL tear was identified by the radiologist in 92% of patients and by the surgeon in 90% of patients (Κ = 0.86). In the second group in which MRI scans were performed within 1-2 months of the injury, the ALL tear was identified by the radiologist in 78% of patients and by the surgeon in 93% of patients (K = 0.62). CONCLUSION: The ALL can be accurately identified on MRI, but the presence and location of ALL tear and its location cannot be reliably identified on MRI. The accuracy in identification and characterization of a tear was affected by the interval between the time of injury and the time when the MRI was performed. LEVEL OF EVIDENCE: Diagnostic, level IIIb, retrospective.

The Segond fracture occurs at the site of lowest sub-entheseal trabecular bone volume fraction on the tibial plateau.

In a series of human cadaveric experiments, Dr. Paul Segond first described the avulsion injury occurring at the anterolateral tibial plateau that later took his name. The fracture is thought to arise as a consequence of excessive tibia internal rotation which often also elicits damage to other connective tissue of the knee. The exact mechanism behind the avulsion is, however, unclear. A number of ligamentous structures have been proposed in separate studies to insert into the Segond fragment. Suggestions include the iliotibial band (ITB), biceps femoris and the controversial 'anterolateral ligament' (ALL). Despite increasing knowledge of tibial plateau bony microarchitecture in both healthy and disease states, no studies have yet, to our knowledge, considered the role of tibial sub-entheseal bone structure in pathogenesis of the Segond fracture. The goal of this study was thus to elucidate the differences in trabecular properties at regions across the tibial plateau in order to provide an explanation for the susceptibility of the anterolateral region to avulsion injury. Twenty human tibial plateaus from cadaveric donors were dissected and imaged using a Nikon-XTH225-µCT scanner with <80 µm isotropic voxel size. Scans were reconstructed using MicroView 3D Image Viewer and Analysis Tool. Subsequent virtual biopsy at ten anatomically defined regions of interest (ROI) generated estimates of bone volume fraction ('bone volume divided by total volume' (BV/TV)). The overall mean BV/TV value across all 20 tibiae and all 10 ROIs was 0.271. Univariate repeated-measurements ANOVA demonstrated that BV/TV values differed between ROIs. BV/TV values at the Segond site (Sα, Sß or Sγ) were lower than all other ROIs at 0.195, 0.192 and 0.193, respectively. This suggests that, notwithstanding inter- and intra-specimen variation, the Segond site tends to have a lower trabecular bone volume fraction than entheseal sites elsewhere on the tibia. Since BV/TV correlates with tensile and torsional strength, the lower BV/TV at the Segond site could equate to a region of local weakness in certain individuals which predisposes them to an avulsion injury following the application of force from excessive internal rotation. The low BV/TV recorded at the Segond site also challenges the idea that the fracture occurs due to pull from a discrete 'anterolateral ligament', as the tension exerted focally would be expected to elicit a hypertrophic response in line with Frost's Mechanostat hypothesis. Our data would instead agree with the aforementioned reports of the fibrous band at the Segond site being part of a broader insertion of an 'anterolateral complex'.

The anterolateral ligament in acute knee trauma: patterns of injury on MR imaging.

OBJECTIVE: To delineate the spectrum of traumatic knee injuries associated with injury of the anterolateral ligament of the knee (ALL). MATERIALS AND METHODS: A retrospective review of 200 MRI scans undertaken for acute knee trauma was performed. In each scan, the ALL was scored as normal, sprained or torn. The menisci, ligaments and tendons of each knee were also assessed. RESULTS: The mean age was 27.4 years (range, 9-69 years), and 71.5% (n = 143) of the patients were male. The anterolateral ligament (ALL) was graded as ruptured in 17 cases (8.5%), sprained in 58 cases (29%), normal in 116 cases (58%) and not visible in 9 cases (4.5%). Of cases with injury of the ALL (n = 75), there was associated injury of the anterior cruciate ligament (ACL) in 61 cases, medial collateral ligament (MCL) in 51 cases, popliteofibular ligament (PFL) in 29 cases, medial meniscus in 29 cases, lateral meniscus in 24 cases, lateral collateral ligament in 9 cases, posterior cruciate ligament in 8 cases, biceps femoris in 5 cases, popliteus tendon in 4 cases and fluid or oedema was seen adjacent to the iliotibial band in 59 cases. No cases of isolated ALL injury were seen. CONCLUSIONS: ALL injury is not uncommon in acute knee trauma and is typically associated with significant internal derangement of the knee, especially anterior cruciate ligament rupture, ITB sprain, medial collateral ligament injury, meniscal tears and injury to the popliteofibular ligament.

Incidence and Prognostic Significance of the Segond Fracture in Patients Undergoing Anterior Cruciate Ligament Reconstruction.

BACKGROUND: The Segond fracture is an avulsion of the anterolateral tibia that can be found in patients with an anterior cruciate ligament (ACL) tear. It is currently unclear if the Segond fracture needs treatment or if it heals spontaneously and if it is associated with an increased risk of failure after ACL reconstruction. PURPOSE: To identify the incidence and spontaneous healing rate of Segond fractures in a consecutive cohort of patients undergoing ACL reconstruction and to examine the predictive value of the Segond fracture on the risk of undergoing revision surgery. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A retrospective review of a cohort undergoing isolated ACL reconstruction between 2002 and 2016 was performed. Radiographs from the time of injury and preoperative radiographs were evaluated for Segond fractures and healed Segond fractures. Descriptive data were extracted from an internal quality database. Statistical analyses were performed to investigate risk of revision surgery and to compare across subgroups of patients. RESULTS: A total of 1364 patients were included in the study. The incidence of Segond fractures was 7.4%. In addition, 10.4% of patients displayed signs of healed Segond fractures. In total, 15.2% of patients had either 1 or both findings. The overall healing response of the fracture was 35.6%. Those with Segond fractures were older (P = .014) and had a shorter interval from injury to surgery (P = .003) as compared with the rest of the cohort. The incidence of Segond fractures was significantly higher in those injured during downhill skiing as compared with other injury mechanisms (P = .04). The Segond fracture did not represent an increased risk of undergoing revision when compared with the control group (not significant). CONCLUSION: The incidence of conventional Segond fractures in patients with ACL injury was found to be in accordance with former studies. Accounting for the high incidence of healed Segond fractures, a much higher incidence (15%) was seen. Although the spontaneous healing rate from initial radiographs to preoperative imaging was only 36%, the presence of Segond fractures did not represent a higher risk of undergoing revision surgery.

¿Es útil fijar las fracturas de Segond para el manejo de la inestabilidad anterolateral de rodilla? A propósito de un caso / Is it worthwhile fixing Segond fractures for the management of anterolateral knee instability? A case report

Introducción El complejo anterolateral de la rodilla es un estabilizador secundario de la rotación tibial interna, su inserción distal esta localizada en el aspecto anterolateral de la tibia proximal y su avulsión es conocida como fractura de Segond, fue descrita hace mas de un siglo por el cirujano francés que le dio su nombre. Es frecuente la asociación de la lesión del ligamento cruzado anterior (LCA) con este complejo, tanto que en la actualidad se considera la fractura de Segond como un signo patognomónico de ruptura del cruzado anterior. Dada la importancia de brindar estabilidad rotacional desde la periferia de la articulación y las propiedades cada vez mas reconocidas de las estructuras anterolaterales, este artículo reporta un caso de fijación directa de la fractura de Segond, en el cual se buscó restituir la anatomía original de la rodilla. Métodos Revisión de la literatura relevante y reporte retrospectivo del caso de un paciente con lesión de LCA y fractura de Segond que fue llevado a reconstrucción de LCA con autoinjerto de HTH y reducción directa y fijación con sutura de anclaje de fractura de Segond por una incisión mínima, con un seguimiento clínico de 4 años. Se aplicaron escalas de valoración subjetiva previo al procedimiento y en el seguimiento postoperatorio. Resultados La inestabilidad anterior y anterolateral posterior al manejo quirúrgico presentó mejoría clínica pasando de tener Lachman IIB a negativo, y Pivot shift grado II a negativo. Las escalas de valoración subjetivas de Lysholm e IKDC mejoraron notablemente de resultados regulares previo al procedimiento a excelentes en el postoperatorio. No presentó complicaciones durante el procedimiento ni requirió reintervenciones. Discusión Aunque la fractura de Segond está descrita desde hace más de un siglo, y su asociación con lesiones de ligamento cruzado anterior se documentó hace mas de 20 años, aun no hay consenso en el manejo de esta fractura. Desde el punto de vista biomecánico, una estructura localizada en el centro de la rodilla como el LCA, de manera aislada, sería insuficiente para controlar la rotación tibial en relación al fémur. Por lo tanto, sería lógico pensar que una estructura localizada lejos del centro de rotación de la rodilla pueda ser más efectiva en controlar la rotación ya que ejerce un mayor control del torque rotacional. Reportamos resultados funcionales satisfactorios y estabilidad postoperatoria adecuada a 4 años de seguimiento, posterior a la fijación de la fractura de Segond asociada a reconstrucción de LCA; consideramos que puede ser una medida exitosa y segura para el manejo de la inestabilidad anterolateral de la rodilla.

Introduction The anterolateral complex of the knee is a secondary stabiliser of the internal tibial rotation. Its distal insertion is located in the anterolateral aspect of the proximal tibia, and its avulsion is known as Segond fracture. This was described more than a century ago by the French surgeon who gave it his name. The combination of anterior cruciate ligament injury (ACL) with the anterolateral complex is so common in as much that Segond fracture is currently considered as a pathognomonic sign of rupture of the anterior cruciate. Given the importance of providing rotational stability from the periphery of the joint and the increasingly recognised properties of the anterolateral structures, this article reports a case of direct fixation of the Segond fracture, in which it was sought to restore the original anatomy of the knee. Methods Review of relevant literature and retrospective case report of a patient with ACL injury and Segond fracture who underwent ACL reconstruction with a host-to-host (HTH) autograft and direct reduction and fixation with Segond fracture anchor suture through a minimal incision. There was a clinical follow-up of 4 years. Subjective assessment scales were applied prior to the procedure and in the postoperative follow-up. Results Anterior and anterolateral instability after surgical management showed a clinical improvement, going from having Lachman IIB to negative, and from Pivot shift grade II to negative. The subjective rating scales of Lysholm and International Knee Documentation Committee (IKDC) improved markedly from regular results prior to the procedure to excellent in the postoperative period. There were no complications during the procedure and no reoperations were required Discussion Although the Segond fracture has been described for more than a century, and its association with anterior cruciate ligament injuries was documented more than 20 years ago, there is still no consensus on the management of this fracture. From the biomechanical point of view, a structure located in the centre of the knee like the ACL, in isolation, would be insufficient to control the tibial rotation in relation to the femur. Therefore, it would be logical to think that a structure located far from the centre of rotation of the knee can be more effective in controlling rotation, since it exerts a greater control of rotational torque. Satisfactory functional results are reported, together with an adequate postoperative stability at 4 years of follow-up, after the fixation of the Segond fracture associated with ACL reconstruction. It is considered that this can be a successful and safe measure for the management of anterolateral instability of the knee.

Joint Effusion and Bone Outlines of the Knee: Radiographic/MR Imaging Correlation.

Knee radiographs are widely used in clinical practice. Many features can be depicted when a systematic analysis of the different views is performed. This article focuses on different types of joint effusion and on the analysis of the bone outlines of the knee, particularly on the lateral view. Systematic analysis of these bone outlines and knowledge of several key points are particularly useful for the depiction of abnormal bone morphology or positioning, and of several conditions, such as trochlear dysplasia, patellar dislocation, impaction fractures, or ligament injuries and avulsion fractures.

Reverse Segond Fracture without Posterior Cruciate Ligament Injury - A report of Two Cases and Review of the Literature.

INTRODUCTION: Reverse Segond fracture is a cortical avulsion fracture off the medial tibial plateau of the knee, associated with tears of the posterior cruciate ligament (PCL), medial collateral ligament (MCL), medial meniscus, and probably the anterior cruciate ligament (ACL). Unlike Segond fracture, it is a very rare injury of the knee. CASE REPORT: Case one is a 24-year-old male with left tibial plateau and reverse Segond fracture with an magnetic resonance imaging (MRI) showing MCL avulsion, medial meniscus entrapped in fracture site and ACL tear but intact PCL. The second case is a 56-year-old female showing reverse Segond and lateral tibial plateau fracture confirmed by X-ray and computed tomography scan. MRI revealed intact PCL, detached medial meniscus from peripheral capsule and ACL injury. CONCLUSION: Based on this study and previous rare reports, reverse Segond fracture may not be accompanied by PCL injuries in all cases.

The anterolateral ligament of the knee and the lateral meniscotibial ligament - Anatomical phantom versus constant structure within the anterolateral complex.

BACKGROUND: Concerning the ongoing controversy about the existence and nature of the anterolateral ligament (ALL) of the knee joint, we reinvestigated the formation of the anterolateral part of its fibrous capsule in anatomic specimens. Furthermore, we wanted to clarify if the lateral meniscus has established a constant anchoring to the lateral tibial condyle via a lateral meniscotibial ligament (lmtl). METHODS: Forty paired embalmed lower extremities taken from 20 human body donors (15 men and five women) underwent exact macroscopic dissection. For the detailed evaluation of the lmtl, additionally 12 specially dissected joint specimens were used. In two of these specimens, the lmtl underwent further histological examination. RESULTS: In all specimens, the anterolateral part of the knee joint fibrous capsule was established by the iliotibial tract and the anterior arm of the aponeurosis of the biceps femoris muscle. According to their close connection and the fact that the anterolateral part of the fibrous capsule is exclusively assembled by these two aponeuroses, they do not leave any space for a distinct ALL connecting the lateral femoral epicondyle and the lateral tibial condyle. The constantly present lmtl was identified as a flat, rectangular bundle of collagen and also elastic fibers reinforcing the inner aspect of the fibrous capsule. Following an oblique direction, it connected the lateral face of the lateral meniscus with the superolateral margin of the lateral tibial condyle. The lmtl measured, on average, 17.1mm in longitudinal and 13mm in anteroposterior direction. CONCLUSION: Our results show that there is no evidence for the existence of an ALL in human knee joints. It is represented either by the iliotibial tract or - most likely - by the anterior arm of the short head of the biceps femoris muscle. On the other hand, the lmtl was found to be a constantly present structure.