Anterior cruciate ligament (ACL) injuries are the most common athletic knee injury requiring reconstruction. In this comprehensive orthopaedic masterclass, we cover everything from the classic non-contact pivot mechanism and clinical assessment to advanced surgical decision-making and graft selection. ⏱ Chapters 0:00 Intro 0:20 Mechanism 0:43 Essentials 1:10 Classification 1:49 Imaging 2:19 Staging 2:44 Algorithm 3:12 Tunnel 3:40 Numbers 4:07 Stability 4:44 Clinical reasoning — Pearls This video provides an in-depth exploration of ACL injuries, designed to build your understanding from essential anatomical principles through to complex operative planning. We delve into the biomechanics of the pivot shift, analyse pathognomonic radiographic signs and MRI kissing contusions, evaluate the pros and cons of bone-patellar tendon-bone versus hamstring and allograft reconstructionsand discuss the critical timing for surgery to prevent arthrofibrosis while optimising return to sport. 🦴 IN THIS VIDEO YOU'LL LEARN • How to identify the classic non-contact deceleration and valgus mechanism of an ACL rupture • The clinical application of Lachman, anterior drawerand pivot shift tests in diagnosing knee instability • Recognising the pathognomonic Segond fracture and deep lateral notch sign on knee radiographs • Interpreting direct and indirect MRI signs, including the posterolateral tibial and lateral femoral condyle kissing contusion pattern • Comparing bone-patellar tendon-bone, hamstring, quadricepsand allograft surgical options for various patient profiles • The importance of delaying surgical reconstruction to restore range of motion and reduce arthrofibrosis risk • The critical principle of anatomic femoral tunnel placement and avoiding the non-anatomic 'high noon' position • Understanding how pivot shift grading correlates with rotational instability and functional outcomes • Counselling patients on the statistical realities of re-injury risk, return to sport timelinesand long-term osteoarthritis development ⏱️ CHAPTERS 📌 KEY TAKEAWAYS ✔️ The ACL is the primary restraint to anterior tibial translation, with rupture causing both translational and rotational instability. ✔️ A Segond fracture on radiographs is pathognomonic for an ACL tear. ✔️ Bone-patellar tendon-bone autograft remains the gold standard for young pivoting athletes due to rapid bone-to-bone integration. ✔️ Avoid allografts in young patients (under 25), as they carry a four times higher failure rate compared to autografts. ✔️ Always restore full knee range of motion before surgery; the optimal surgical window is between four and twelve weeks post-injury. ✔️ Femoral tunnel placement must be anatomical at the centre of the native footprint to restore native knee kinematics. 👩⚕️ WHO THIS IS FOR This masterclass is essential for orthopaedic trainees, junior doctorsand medical students seeking a comprehensive understanding of sports knee injuries. Clinicians managing acute trauma and interested patients wanting to understand ACL reconstruction and recovery will also find it highly valuable. 📚 RELATED TOPICS: Segond Fracture and Anterolateral Ligament Complex Injuries · Bone-Patellar Tendon-Bone versus Hamstring Autograft Biomechanics · Pivot Shift Test Grading and Rotational Knee Instability · Anatomic ACL Reconstruction and Femoral Tunnel Landmarks · Arthrofibrosis Prevention and Postoperative ACL Rehabilitation · Acute Haemarthrosis Differential Diagnosis 🔗 More free orthopaedic teaching at Orthovellum.com — subscribe for weekly videos. 🎨 CREDITS • Original Orthovellum production. ⚠️ DISCLAIMER: Educational only — not individual medical advice. Always consult a qualified clinician for diagnosis and treatment. #orthopaedics #orthovellum #aclinjury #kneesurgery #sportsmedicine #aclreconstruction #kneeinstability #sportsinjury #acltear #orthopedicsurgery #kneepain #pivots