Sports (2008-2019) Flashcards

Question

25. Which of the following is true about cruciate synovial cysts? 1. Cause pain during deep squatting 2. Are very rare and have no classification system 3. Are impossible to distinguish from synovial sarcoma on MRI/"are confused with" 4. Have a high risk of recurrence following arthroscopic excision

Answer 1

ANSWER - A 2014 Cysts about the Knee: Evaluation and Management. JAAOS August 2013 * B - Untrue: Prevalence of 0.2 to 1.9%, and classification is anterior to ACL, between ACL and PCL and posterior to PCL * A - True: Pain can be intermittent or constant, and often worse with exercise especially squatting (squeezing the cyst) * D - Untrue: Arthroscopic excision is the treatment of choice with “no” symptomatic recurrences * C - Untrue: Although the differential includes other ganglion cysts, hemangioma, synovial sarcoma and villonodular synovitis these pathologies should have unique MRI features that should lead to proper diagnosis

Answer 2

ANSWER: B 2011 * Oiestad (AJSM 2009) Knee osteoarthritis after anterior cruciate ligament injury * Predictors of OA: * Obesity * Chondrosis in medial compartment \> grade 2 * Prior medial menisectomy * Longer duration of follow up * Female * PF chondrosis * Prior lateral menisectomy

Answer 3

ANSWER: A 2011 JAAOS 1999 - Loss of extension after reconstruction of the ACL * Ideal place for the tunnel is 3mm posterior to the center of the origin of the ACL * Orthobullets * Tibial tunnel should be 10-11mm in front of the anterior border of PCL insertion

Answer 4

ANSWER: B 2011 JAAOS 1999 - Loss of extension after reconstruction of the ACL * Some biomechanical studies that there is a loss of extension with tightening in 30o * Areneja (Arthroscopy 2009) * No difference in a systematic review of papers tightening in full extension, 30o flexion, 10o flexion JAAOS 2012 – Graft tensionin during knee ligament reconstruction: * Some biomech studies say decrease extension if overtension at 30 degrees (most studies look at 30 degrees) * Consensus is that you can tension at full extension or 30 degrees (more common at Western) * Maximum tensioning at full extension OR submaximum loading/tensioning at 30 degrees (which is why we use the tensionometer)

Answer 5

ANSWER: A 2008 * Wheeless: * Hyper-extension * At 5o of hyperextension the ACL ligament forces range between 50 and 240 Newtons * Hyperextension of the knee develops much higher forces in ACL than in the PCL * ACL strain at 30o of knee flexion are significant higher than at 90o where the ligament remains unstrained * Frank (JBJS 1997) Current Concepts Review * Extensive in vitro and in vivo evidence has shown that the circumstances that cause the highest loads and strains on the ACL during daily function are quadriceps-powered extension of the knee, moving it from approximately 40o of flexion to full extension; hyperextension of the knee; excessive internal tibial rotation; or excessive varus or valgus stress on the tibia * 2018 - A Review on Biomechanics of Anterior Cruciate Ligament and Materials for Reconstruction * the highest shear forces on the anterior cruciate ligament occur during hyperextension/low flexion angles of the knee joint

Answer 6

ANSWER: C 2008 Frank (JBJS 1997) Current Concepts Review * ®Frank, JBJS, Current Concepts Review, 1997 - highest loads and strains during daily function on ACL are during quad powered extension from 40° to hyperextension * PCL * - Level Walking = 352 N * - Ascending Stairs = 641 N * - Descending Stairs = 262 N * - Ascending Ramp = 1215 N * - Descending Ramp = 449 N * ACL * - Level Walking = 169 N * - Ascending Stairs = 67 N * - Descending Stairs = 445 N * - Ascending Ramp = 27 N * - Descending Ramp = 93 N

Answer 7

ANSWER: C (prob best answer) or D (also say histologic evidence of chondrocyte damage in 35%) * A: False Bone bruising on lateral side of femur and tibia. Middle 1/3 of lateral femoral condyle and posterior 1/3 of lateral tibial plateau. The plateau comes forward under the femur during injury and impact in the middle third of the femur. * B: False M- ore than 80% * Graf, Am J Sp Med, 1993 - middle third of the lateral femoral condyle and the posterior third of the lateral tibial plateau, no correlation with position or location of meniscus injury, 48% had bone bruising * Treatment of ACL Injuries, Part I; Vol.33,No.10,2005; p.1583 “Several investigators reported 80% or more of ACL injuries were associated with bone bruises in the lateral compartment.” * Mair, Am J Sp Med, 2004 – PCL injury with 83% isolated injury of PCL and at least one bruise * Costa-paz, Arthroscopy, 2001 – f/u MRI with ACL and bone bruise after recon, 24 to 64 months post op, 71% gone, 29% retained suggesting OC injury * Davies, Clinical Radiology, 2004 – bone bruises persist longer than 12 to 14 weeks, more than previously thought, 67% had ACL injuries, 23% collateral injuries, 10% no assoc lig injury, no correlation in bruise size or location with type of or lack of injury

Answer 8

ANSWER: B Grade 3 MCL gets residual laxity, not a functional problem. Controversial what to do for combined but some suggest trial nonop. 2008 * Combined anterior and posterior cruciate and medial collateral ligament injury: nonsurgical and delayed surgical treatment (ICL 2003) * "anterior cruciate ligament injuries in combination with medial collateral ligament and/or PCL injury can initially be treated nonsurgically and reconstructed later as dictated by patient symptoms and activity level." * Medvecky M (Sports Med and Arthrosc Revew 2015) Management of Acute combined ACL-Medial and posteromedial instability of the knee * There is fairly uniform consensus in the literature that non-operative management of first-degree and second-degree injuries is appropriate. With regard to acute third-degree medial-sided injuries, some controversy does exist regarding non-operative versus operative intervention. However, most studies advocate non-operative treatment of medial-sided injury * Recommend short term immobilization in extension * Previous answer (2008 toronto and 2008 UWO) is grade 3 MCL gets residual laxity. All agree that isolated grade 3 gets nonop initially but highly controversial if treat nonop or op for combined ACL and grade 3. Would try non-op and brace first.

Answer 9

ANSWER - D * Treatment of Medial Collateral Ligament Injuries. JAAOS 2009 * Most commonly a rupture at the femoral insertion, however an avulsion with bony fragment is an indication for acute fixation. * Pellegrini-Stieda Syndrome is recalcification at the femoral insertion * Return to Sport: * Serscheid and Garrick (AJSM 1981) * Grade II: In high school football series average return in 19.5 days * Grade I: In high school football average return in 10.6 days * Jones (Clin Orthop 1986): * Grade III injuries in high school players average return in 34 days * ACL tears comprise up to 95% of associated injuries; 20% are with grade I MCL injuries, 52% are with grade II MCL injuries, 78% are with grade III injuries * Should be able to pick up on MR or clinical exam * Kim C (Clin Sport Med 2016) Return to Play after MCL Injury * Not great evidence, review article * Conservative management - 5-7 weeks to return to play * Operative - 6-9 months * Definitely some injury severity bias * JAAOS 2017 - Physical examination of knee ligament injuries * Agree MCL usually tears from femoral side - check for point tenderness at medial epicondyle * Valgus stress should be done at both 0deg and 30deg; 30deg helps isolate sMCL

Answer 10

ANSWER - A 2011, 2014 * From: The knee meniscus: Structure-function, pathophysiology, current repair techniques, and prospects for regeneration. E.A. Makris et al. / Biomaterials 32 (2011) 7411-7431 * “The biomechanical properties of the knee meniscus are appropriately tuned to withstand the forces exerted on the tissue. Many studies have helped to quantify the properties of the tissue both in humans and in animal models. According to these studies, the meniscus resists axial compression with an aggregate modulus of 100-150 kPa. The tensile modulus of the tissue varies between the circumferential and radial directions; it is approximately 100-300 MPa circumferentially and 10-fold lower than this radially.” * From The meniscus: Review of basic principles with application to surgery and rehabilition (J Athl Train 2001) * Three collagen fiber layers are specifically arranged to convert compressive loads into circumferential or “hoop” stresses (Figure (Figure4).4). In the superficial layer, the fibers travel radially, serving as “ties” that resist shearing or splitting. In the middle layer, the fibers run parallel or circumferentially to resist hoop stress during weight bearing. Lastly, there is a deep layer of collagen bundles that are aligned parallel to the periphery * 70% water, 30% organic; Type II collagen is main component, GAGs 1%