Ligamentous and Meniscal Injuries: Diagnosis and Management Daniel K Williams, MD Franciscan Physician Network Orthopedic Specialists September 29, 2017
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INTRODUCTION Overview of pertinent anatomy Osseous anatomy Muscular anatomy Ligamentous anatomy Meniscal anatomy Applied physical examination Common topics and pearls
KNEE ANATOMY--OVERVIEW Comprised of four bones Distal femur Proximal tibia Proximal fibula Patella Femur converges toward midline to meet nearly vertical tibia Anatomical axis Meet around 5-12 degrees
MUSCLE GROUPS Quadriceps muscle group Rectus femoris Vastus lateralis Vastus medialis Vastus intermedius Quadriceps tendon Superior portion of extensor mechanism
Hamstrings Biceps femoris Semimembranosus Semitendinosus Primary knee flexors Hamstrings Sartorius Gracilis Popliteus gastrocnemius MUSCLE GROUPS
KNEE LIGAMENTS Medial collateral ligament Lateral collateral ligament Anterior cruciate ligament Posterior cruciate ligament Medial patellofemoral ligament
MCL Composed of superficial/deep portions Superficial MCL Proximal: posterior aspect of medial femoral condyle Distal: metaphyseal region of tibia Primary valgus restraint depending on flexion At 25º flexion, 80% restraint At 5º flexion, 60% restraint Deep MCL Separated by bursa Attaches directly into edge of tibial plateau and meniscus Does not contribute to valgus restraint
LCL Proximal: posterior lateral condyle Distal: lateral base of fibular head Conjoint tendon BFT Primary restraint to varus stress at 5º and 25º of flexion At full extension, resists 55% of varus load Isolated injury uncommon
ANTERIOR CRUCIATE LIGAMENT Femoral side: arises from posteromedial corner of medial aspect of lateral femoral condyle Tibial side: in fossa anterior and lateral to tibial spine Two bundles: named for tibial insertion Anteromedial tight in flexion Posterolateral tight in extension Provides anterior and rotational restraint of the tibia in relation to the femur
POSTERIOR CRUCIATE LIGAMENT Technically extraarticular Broad femoral origin at PL medial condyle Insertion centrally on posterior tibia Primary restraint to posterior tibial translation Secondary restraint to external tibial rotation
MEDIAL PATELLOFEMORAL LIGAMENT Distinct condensation of capsular fibers Originates from medial epicondyle and MCL Deep to VMO to attach to superior aspect of patella Provides 50% to 80% restraining force to lateral patella dislocation
MENISCI Medial and lateral Semilunar fibrocartilaginous disks Interposed b/t femoral and tibial condyles Counteract hoop stress with weight bearing Dissipates load to articular cartilage and subchondral bone Knee extension: 50% of axial load Knee flexion: 85% of axial load Joint stability/congruity Only 10% to 30% peripheral vascularized: lateral and medial genicular arteries
PHYSICAL EXAM Observation/alignment ROM Active Passive Normal ROM -5º to 143º in women Normal ROM -6º to 140º in men Palpation Tendonitis Joint line pain etc Strength Gait Specific physical exam maneuvers
OBSERVATION
ANTERIOR/POSTERIOR INSTABILITY Lachman s Test Anterior drawer Tibial drop back test Posterior drawer test
LACHMAN S TEST Assess ACL Knee 15º flexion Stabilize distal femur, anteriorly translate proximal tibia Quantify displacement in mm Soft vs hard endpoint Clinically Mild 0-5mm displacement Moderate 6-10 mm displacement Severe 11-15 mm displacement
Assess ACL ANTERIOR DRAWER Flex knee to 80º Stabilize foot in neutral rotation Anterior force applied to tibia Compare to nl side
TIBIAL DROP BACK TEST Compare prominence of proximal tibia to femoral condyles with knees flexed 80º In nl knee, tibia 1 cm anterior to condyles Assess PCL
POSTERIOR DRAWER Most accurate for PCL integrity Knee flexed to 90 w/ posterior force on tibia Normal plateau 1 cm anterior to condyle Grade I: excessive translation but maintenance of anterior step-off Grade II: 5-10mm translation but not posterior to condyle Grade III: >10mm translation/posterior to condyle
MCL COMPLEX INSTABILITY Valgus stress test at 0º Valgus stress test at 30º
VALGUS STRESS AT 0º Assess MCL/ multiligamentous injury Start with knee in extension Fingers over joint line Apply valgus stress Compare to nl side
VALGUS STRESS AT 30º Isolates MCL Similar technique as before
PATELLOFEMORAL TESTS Patellar grind test (Clarke s Sign) Zohler s Sign Lateral patellar apprehension test Medial patellar apprehension
PATELLAR GRIND TEST Patient relaxed with knee extended Examiner presses down onto patella with palm of hand Patient actively contracts quadriceps Test negative if no pain Repeat several times with increasing force
LATERAL PATELLAR APPREHENSION Knee fully relaxed, 45º flexion One hand stabilizes leg Lateral force on patella Amount of subluxation/translation graded based on 4 quadrants of patella Hypermobility >3 quadrants of translation
MENISCAL TESTS Palpation/joint line tenderness McMurray s Apley s Steinman s Spring Sign
MCMURRAY S TEST Patient s knee acutely/forcibly flexed Fingers placed on medial lateral joint line Tibia interanally/externally rotated and extended Positive if pain or feeling of a click
APLEY S TEST Patient prone with knee flexed to 90º Examiner stabilizes thigh Tibia compressed into knee with external rotation
STEINMANN S TEST Patient sitting at end of exam table Knee flexed to 90º Examiner internally/externally rotates foot Positive if internal rotation=lateral pain or external rotation=medial pain Repeat in various degrees of knee flexion
SPRING SIGN Patient supine on table Relaxed leg/knee in extension Examiner holds ankle with knee in extension Holds knee slightly flexed with other hand Release hold on knee and allow knee to fall into extension Positive if pain or knee springs back
Common Knee Pathology From PCPs My Experience and Personal Pearls Patellofemoral Pain ACL tears Meniscus Tears MCL Sprains Patella Instability/Dislocation Bursitis
Patellofemoral Pain My personal pain 2 finger sign Pain with stairs, sitting for long time, driving, etc. Sunrise view on plain xrays can be beneficial Usually from a kinematic imbalance/muscular group weakness Look at their feet For me, usually nonoperative PT, PT, and more PT Knee braces Shoe inserts Anti-inflammatories injections
ACL Tears Could have entire week of talks dedicated to this injury If you suspect it or have diagnosed it, then refer it Do all ACL tears need to be fixed? Nope Patient life style, activity level, amount of OA can help decide
Meniscus Tears Acute vs Chronic Joint Line Pain Sharp, mechanical pain Catching, giving, out Worse with pivoting/twisting Xrays, xrays, xrays!!!! MRI for some Conservative vs operative treatment surgeon/patient specific
MCL Injuries Hit from the lateral side of the knee Can be noncontact esp. when in combination with other injuries Xrays, Xrays, Xrays!!! MRI to confirm and r/o other injuries Grades 1 to 3 Most all isolated can be treated conservatively Hinged knee brace PT Few need surgical intervention
Patella Dislocation Twist with a clunk Some have to be reduced in ER Xrays, xrays, xrays!!!...esp sunrise view MRI As a general rule, most first time patella dislocators can be treated conservatively Lateral J brace PT
Prepatellar Bursitis Swelling anterior to patella Common in people on knees for work Conservative Treatment Rest, ice, anti-inflammatories Avoid kneeling Cushioned knee brace/pad Aspirate/injection Pes Anserine Bursitis Easy diagnosis Point tender over pes Conservative Treatment Ice, anti-inflammatories Injection PT
CONCLUSION Knee complicated anatomy Knowing anatomy=knowing diagnosis Multiple physical exam maneuvers Choose those most comfortable with and have been reliable in the past Always get xrays first!!!!
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