The Knee Knee Joint “Modified” Hinge Joint Movement in flexion/extension Some internal/external tibia rotation Synovial Joint Fibrous joint capsule Filled with synovial fluid Bones • Femur • Tibia • Fibula • Patella (Sesamoid Bone) • Reduces tendon friction, enhances mechanical advantage of the joint. Ligaments Cruciate ACL/PCL Collateral MCL/LCL Ligament Stress Normal Adducted/Varus Abducted/Valgus Adducted /Varus: LCL Abducted/Valgus: MCL Ligament Stress PCL Injury ACL Injury Posterior translation of Tibia on Anterior Translation of Femur Tibia on Femur Cartilage Articular Provides frictionless surface Fibrous “Fibrocartilage” Meniscus- shock absorbing Deepen articular facets Medial Meniscus C –shaped Lateral Meniscus O-shaped Meniscal Blood Supply Red Zone: Outer 1/3rd of the meniscus that receives good blood supply & is repairable and easier to heal Red-White Zone: Area in between the Red & White Zones of the meniscus where there is some blood supply, and becomes harder to repair and heal White Zone: Inner 2/3rds of the meniscus that receives little to no blood supply and is harder to repair and rarely heals. Bursae Fluid filled sacs Synovial in nature Purpose: Reduce friction in mobile areas (muscle and tendon movement over joint) Musculature: Quadriceps Rectus Femoris Action: Extends leg, flexes thigh Origin: Illium & Iliac Spine Insertion: Tibial Tuberosity vis quadriceps/patella tendon Vastus Lateralis Action: Extends leg Origin: Greater Trochanter Insertion: Tibial Tuberosity vis quadriceps/patella tendon Musculature: Quadriceps Vastus Medialis Action: Extends leg Origin: Lesser Trochanter Insertion: Medial Patella, Tibial Tuberosity vis quadriceps/patella tendon Vastus Intermedius Action: Extends Leg Origin: Proximal Femur Insertion: Tibial Tuberosity vis quadriceps/patella tendon Musculature: Hamstrings Biceps Femoris Action: Flexes leg, Extends thigh Origin: Ischial Tuberosity, Sacrum Insertion: Lateral Fibula Head, Lateral Tibia Condyle Semitendinosus Action: Flexes Leg Origin: Ischial Tuberosity Insertion: Medial Tibial Shaft Semimembranosus Action: Flexes Leg Origin: Ischial Tuberosity Insertion: Medial Condyle Of Tibia Musculature: Abductors Gluteus Maximus Action: Abducts thigh, External Rotation of hip Origin: Illium, Sacrum, Coccyx Insertion: Gluteal Tuberosity Gluteus Medius Action: Abducts thigh, Internal Rotation of hip Origin: Illium, Illiac Crest Insertion: Greater Trochanter Gluteus Minimus Action: Abducts thigh, Internal Rotation of hip Origin: Illium Insertion: Greater Trochanter Musculature: Abductors Tens or Fa s c i a e Latae Action: Abducts thigh Origin: Illiac Crest Insertion: Lateral Tibial Condyle, IT Band Sartorius Action: Abducts thigh, flexes knee, externally rotates hip Origin: Illium Insertion: Medial proximal tibia Musculature: Adductors Gracilis Action: Adducts thigh, Flexes knee Origin: Pubis Insertion: Medial Shaft of Tibia Adductor Longus Action: Adducts thigh Origin: Pubis Insertion: Shaft of Femur Musculature: Adductors Adductor Brevis Action: Adducts thigh Origin: Pubis Insertion: Lesser Trochanter Adductor Magnus Action: Adducts thigh Origin: Pubis Insertion: Posterior Medial Condyle of Femur Prevention Proper hamstring to quadriceps strength ratio There needs to be equal amounts of force muscular strength between the hamstrings & quadriceps Flexibility of hamstrings, quadriceps, hip flexor, and lower leg musculature Agility & Proprioceptive Training Bracing Injuries Ligament Sprains: Grade Characteristics Grade 1 Fibers stretched, minimal to no laxity, minimal swelling, pain Grade 2 Some fibers torn, noticeable laxity and or instability, moderate swelling, increased pain Grade 3 Complete rupture, severe laxity and or instability, severe swelling, severe pain that dissipates Ligament Sprains: MOI/Treatment ACL MOI Non-contact: Foot planted with pivoting at thigh Axial load (rotational) with tibial internal rotation and valgus stress Contact: Hyperextension from blow to knee (damage to other structures) S/S Athlete feels a “pop” Immediate disability Rapid swelling “knee is shifting” Increased ligament/joint laxity Ligament Sprains: MOI/Treatment ACL Tx: Grade 1: RICE Immobilize 2-3 days Recovery: 1-3 weeks Grade 2: RICE Immobilize about 1 week Recovery: ≥ 3 weeks Evaluation: Grade 3: RICE • Anterior Drawer Surgery • Lachman’s Recovery up to 1 year • Pivot Shift Rehabilitation: • Lever’s Sign Post Surgery Extension ROM and Isometrics immediately ROM after immobilization Progressive strength training (focus on quads strengthening) Brace for first 6 weeks; Brace for RTP Ligament Sprains: MOI/Treatment PCL MOI: Blow to anterior tibia Fall on flexed knee “Dashboard injury” – car accident causing knee to hit dashboard forcing tibia posteriorly S/S: “pop” in posterior knee Posterior knee laxity Evaluation: Posterior Drawer Godfrey’s 90/90 Ligament Sprains: MOI/Treatment PCL Tx: Grade 1: RICE Immobilize 2-3 days Recovery: 1-3 weeks Grade 2: RICE Immobilize about 1 week Recovery: ≥ 3 weeks Grade 3: RICE Surgery? Recovery > 4 months Rehabilitation Post Surgery Immobilize for 6 weeks ROM/Strength after ROM/Progressive Strength Quad strengthening Ligament Sprains: MOI/Treatment MCL/LCL MOI: MCL: Valgus LCL: Varus stress S/S: MCL: Laxity on medial side Tenderness on medial side Swelling centralized on medial aspect Evaluation: LCL: Laxity on lateral side • MCL: Varus Stress Test • LCL: Valgus Stress Test Tenderness on lateral side Less common Ligament Sprains: MOI/Treatment Tx: Grade 1: RICE Immobilize 2-3 days Recovery: 1-3 weeks Grade 2: RICE Immobilize about 1 week Recovery: 4-6 weeks Grade 3: RICE Immobilize/brace 2-3 weeks Surgery? Recovery time varies Rehabilitation ROM after immobilization Strength – all knee musculature Balance & plyometrics Brace Meniscus Tear Meniscectomy Partial or complete removal of meniscus MOI: RTP 1-2 weeks but could lead to Plant and cut arthritis in long term Forced extension Int rotation of femur S/S: • Evaluation: Joint line pain • McMurray’s Test • Swelling Apley’s Compression & Distraction Test Locking/giving out • Thessaly Test Clicking Pain with squatting Tx: RICE NSAIDS Immobilize Refer-Surgery Red zone – Surgery, White zone –Not recommended IT Band Syndrome MOI: Frequent distance running Tight musculature Foot pronation S/S: Painful PPT at insertion site Tight ITB Tx: Stretching Hip strengthening Ice, Massage, etc. Osgood-Schlatter Disease Excessive calcification of tibial Tx: tuberosity (Apoyhysis) Decrease activity Common in young athletes Ice MOI: Isometric strengthening Repeated pulling of patellar 6 months – 1 yr to heal tendon on tibial tuberosity S/S Pain with kneeling, jumping, running Point tenderness over tubercle Enlarged tibial tubercle Patella Fracture MOI: Tx: Direct Trauma Immediate splint Forced quad contraction Possible surgery when knee is flexed. Immobilize for 2-3 months S/S: Regain ROM/strength Pain Can take several months Swelling Immobility Visible or palpable deformity Patellar Dislocation MOI: Tx: plant and cut in opposite Immobilize for ≥4 weeks direction of planted foot Regain ROM/strength Most occur laterally 1-2 months Caused by muscular Surgery if frequent imbalance dislocation S/S: Pain Swelling Immobility Visible misalignment Patellar Tendinitis MOI: Treatment ideas: “jumper’s knee” Ice, Switch to heat before Excessive jumping, activity , massage, running ultrasound Tight quads Stretching/ Strengthening S/S: Pain between patella and tibial tuberosity Stage 1: pain after activity Stage 2: pain during and after activity Stage 3: Pain during and long after activity Crepitus Patellar Tendon Rupture MOI: Tx: Chronic inflammation Surgically repair tendon Sudden quad contraction Recovery ≈ 4 months S/S: ROM/Strength Patella migrates superiorly Cannot extend knee Swelling Sharp pain that dissipates.