Chapter 6Assessment of AcuteKnee Injuries

Objectives

Discuss the anatomical structures of the knee

Identify and discuss the common acute injuries to the knee

Review the following components of injury assessment related to the acute knee injuries

Mechanism of injury

Signs

Symptoms

Bones

Femur* Tibia* Fibula Patella

*articulating surface covered with a smooth layer of articular cartilage (also referred to as hyaline cartilage)

Bones

Femur* Tibia* Fibula Patella*

*articulating surface covered with a smooth layer of articular cartilage (also referred to as hyaline cartilage)

Joints

Tibiofemoral Proximal tibiofibular patellofemoral

Ligaments

Joint capsule Medial collateral ligament (MCL)Medial collateral ligament (MCL)

Protects against lateral forcesProtects against lateral forces Lateral collateral ligament (LCL)Lateral collateral ligament (LCL)

Protects against medial forcesProtects against medial forces

Joint capsule Medial collateral ligament (MCL)Medial collateral ligament (MCL)

Protects against lateral forcesProtects against lateral forces Lateral collateral ligament (LCL)Lateral collateral ligament (LCL)

Protects against medial forcesProtects against medial forces

Ligaments

Joint capsule Anterior cruciate ligament (ACL)Anterior cruciate ligament (ACL)

Prevents the tibia from moving Prevents the tibia from moving forward or the femur from moving forward or the femur from moving backwardbackward

Posterior cruciate ligament (PCL)Posterior cruciate ligament (PCL) Prevents the tibia from moving Prevents the tibia from moving

backward or the femur from movingbackward or the femur from movingforwardforward

Joint capsule Anterior cruciate ligament (ACL)Anterior cruciate ligament (ACL)

Prevents the tibia from moving Prevents the tibia from moving forward or the femur from moving forward or the femur from moving backwardbackward

Posterior cruciate ligament (PCL)Posterior cruciate ligament (PCL) Prevents the tibia from moving Prevents the tibia from moving

backward or the femur from movingbackward or the femur from movingforwardforward

Menisci (Cartilage)

Medial meniscus (C-shaped) Injured more frequently

Less mobile Attaches to MCL ligament

Menisci (Cartilage)

Lateral meniscus (O-shaped)Lateral meniscus (O-shaped) Injured less frequently

more mobile

Menisci (Cartilage)

FunctionFunction Provide stability Provide shock absorbency Lubricate, reduce friction

Muscles

Quadriceps (anterior) Hamstrings (posterior) Adductors (medial) Iliotibial band (lateral)

Muscles

Patellar Tendon

Common Acute Knee Injuries

Contusion Meniscal injury Sprain Strain Chondral lesion Fracture Dislocation

Contusions to the Knee

MOI

Signs

Symptoms

Meniscal Injuries

MOI

Signs

Symptoms

Meniscal Injuries

Meniscal Injuries

Flap tearFlap tear

Meniscal Injuries

Meniscal Injuries

Sprains to the Knee

Medial (tibial) collateral (MCL) Lateral (fibular) collateral (LCL) Anterior cruciate (ACL) Posterior cruciate (PCL)

Posterior ViewPosterior View

Anterior ViewAnterior View

MCL Sprains

MOI

Signs

Symptoms

LCL Sprains

MOI

Signs

Symptoms

ACL Sprains

MOI

Signs

Symptoms

PCL Sprains

MOI

Signs

Symptoms

Patellofemoral Syndrome

MOI

Signs

Symptoms

Patellar Tendinitis

MOI

Signs

Symptoms