Lateral femoral notch sign and posterolateral tibial plateau fractures and their associated injuries in the setting of an anterior cruciate ligament rupture

Introduction ACL injury is one of the most common injuries of the knee joint in sports. As accompanying osseous injuries of the ACL rupture a femoral impression the so-called lateral femoral notch sign and a posterolateral fracture of the tibial plateau are described. However, frequency, concomitant ligament injuries and when and how to treat these combined injuries are not clear. There is still a lack of understanding with which ligamentous concomitant injuries besides the anterior cruciate ligament injury these bony injuries are associated. Materials and methods One hundred fifteen MRI scans with proven anterior cruciate ligament rupture performed at our center were retrospectively evaluated for the presence of a meniscus, collateral ligament injury, a femoral impression, or a posterolateral impression fracture. Femoral impressions were described according to their local appearance and posterolateral tibial plateau fractures were described using the classification of Menzdorf et al. Results In 29 cases a significant impression in the lateral femoral condyle was detected. There was a significantly increased number of lateral meniscal (41.4% vs. 18.6% p = 0.023) and medial ligament (41.4% vs. 22.1%; p = 0.040) injuries in the group with a lateral femoral notch sign. 104 patients showed a posterolateral bone bruise or fracture of the tibial plateau. Seven of these required an intervention according to Menzdorf et al. In the group of anterior cruciate ligament injuries with posterolateral tibial plateau fracture significantly more lateral meniscus injuries were seen (p = 0.039). Conclusion In the preoperative planning of ACL rupture accompanied with a positive femoral notch sign, attention should be paid to possible medial collateral ligament and lateral meniscus injuries. As these are more likely to occur together. A posterolateral impression fracture of the tibial plateau is associated with an increased likelihood of the presence of a lateral meniscal injury. This must be considered in surgical therapy and planning and may be the indication for necessary early surgical treatment.

Extra-articular Medial Impression Fracture of the Talus: A Previously Undescribed Injury

Background: Peripheral fractures of the talus are uncommon. Almost all the literature regarding talar fractures consists of central intra-articular fractures, whereas studies about peripheral talar fractures are lacking. The aim of this study is to increase awareness in diagnosing an unusual peripheral extra-articular medial impression fracture of the talus. Methods: This study includes a retrospective case series of patients with an extra-articular medial impression fracture of the talus. Patient characteristics, trauma mechanism, diagnostics, fracture characteristics, and treatment were reported. Results: Eight consecutive patients with an extra-articular medial impression fracture of the talus were identified. In 80%, the trauma mechanism was a supination or inversion injury of the ankle and foot. An X-ray was obtained in all patients; in 7 (88%) patients, a computed tomography scan was done, and an additional magnetic resonance imaging was done in 3 (38%) patients. In 4 patients (50%), the correct diagnosis was missed at first presentation. The delay between injury and diagnosis was 0 to 180 days (of 36 days on average). Conclusion: This is the first case series to describe patients with a peripheral extra-articular medial impression fracture of the talus. Good clinical examination and judicious use of diagnostic imaging are a necessity to find the talar impression fractures in a timely manner, and treatment can be started immediately. Levels of Evidence: Level V

Lateral Clavicular Autograft for Repair of Reverse Hill-Sachs Defect

Posterior dislocations of the shoulder joint can result in an impression fracture over the anteromedial humeral head, termed the reverse Hill-Sachs lesion, the presence of which can contribute to recurrent dislocations. Methods described to repair this defect include using allografts, iliac crest and coracoid process autografts, and bone graft substitutes. We describe a novel technique using the lateral end of the ipsilateral clavicle as an autograft in a 78 year old man with a reverse Hill Sachs lesion. This graft can be harvested through the same incision and does not compromise the stability of the acromioclavicular joint or any future shoulder arthroplasty.