The Athlete’s Knee

The Athlete’s Knee
Presentation by:
John R. (Trey) Green, III, MD
University of Washington
Sports Medicine Clinic
206-543-1552

Anterior Knee Anatomy
* Superficial fascia
* Quadriceps muscle group
* Patella
* Synovium / plicae
* Bursae

Anterior Knee Anatomy
* Quadriceps muscle group
o Rectus femoris
o Vastus medialis
o Vastus lateralis
o Vastus intermedius

Quadriceps Muscle Group
* Vastus medialis
o Larger, and more distal insertion than vastus lateralis
o Oblique distal fibers (VMO)

Patella Articular Surface

* Thickest articular cartilage in the body (5mm)
* 25% non articular (inferior pole)

Anterior Knee Anatomy

* Bursae
o Occur to assist tissue gliding
o Variable location

Patellofemoral Biomechanics

* Patella function
o Act as a fulcrum to increase the lever arm of the quadriceps muscle

Resultant Force on the Patella

* Compression
* 2-3 x body weight
* Maximum force at 70-80 degrees of flexion

Q Angle

* Angle between the quadriceps tendon and patella tendon in full extension

Anterior Knee Pain History
* Pain
* Instability
* Catching
* Crepitation
* Weakness
* Swelling

Physical Examination

* Gait

Physical Examination

* Limb length

Physical Examination
* Compartment assessment (crepitation)
* Observation
Effusion
Prepatellar Bursal Fluid
* Range of Motion (ROM)
* Anterior knee
* Patellar position
* Patellar tracking
* Muscle tone/bulk
* Thigh circumference
* Sitting
* Lying
* Hip abductor strength
* Prone quadriceps tightness

Radiologic Examination
Rosenberg View
Merchant View
Measuring Merchant’sView
Anterior Knee Pain Treatment
* Rehab with therapist
Anterior Knee Pain Treatment
* Refer to Orthopaedist

Assessment of Meniscus, Ligament and Articular Cartilage Injuries
* Most require orthopaedic consultation
History
Pain Location
Meniscus Tears
* Meniscus tears are common
* Rapid flexion with rotation is most common mechanism
* A history of mechanical symptoms and joint line pain and tenderness suggests meniscal tear
Meniscus Tear Types
Meniscus Tears
* Arthroscopy is the gold standard for diagnosis and treatment
* Basic principles of meniscus surgery are:
o Conserve meniscal tissue
o Remove abnormal tissue
o Prevent further tear propagation
o Repair when possible
Articular Cartilage Injury
* Limited intrinsic repair capability
* Likely to eventually progress to arthrosis
* History of pain with recurrent effusions may indicate cartilage lesion
Articular CartilageTreatment Options
Medial Collateral Ligament
Beware Co-existing ACL or PCL Injury
Lateral Sided Ligament Injury
ACL Tear
PCL Tears
Knee Physical Exam
Physical Examination
Collateral Ligament Testing

The Athlete’s Knee.ppt

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Blood Brain Barrier: Structure, Function and Bypass by Microorganisms

Discovery
What is the Blood Brain Barrier?
Structure of Blood Brain Barrier
Integrity of BBB
Astrocyte end feet
Tight Junctions between BMEC
Claudin
Occludin
Barrier Function of Occludin and Claudin
Junction Adhesion Molecules:
BMEC intercellular space
Barrier function of JAM
Cytoplasmic accessory proteins
Membrane associated guanylate kinase-like proteins (MAGUKS)
Adherens Junction
Pericytes
Astrocyte end feet
Circumventricular organs
Circumventricular organ functions:
Normal BBB transport
Factors produced by astrocytes
Glutamate,
Aspartate
Taurine
ATP
Endothelin-1
NO
MIP-2
Tumor necrosis factor alpha TNF-α
Interleukin beta IL-β
Bradykin
5HT
Histamine
Thrombin
UTP
UMP
Substance P
Qionolonic acid
Platelet activating factor
Free radicals
E. Coli model
Physical damage of BBB
Ligand receptor interactions followed by host cell actin cytoskeletal rearrangements
Transcellular transport while maintaining integrity of BMEC
Physcial damage of BBB
Conclusion
References



Blood Brain Barrier: Structure, Function and Bypass by Microorganisms Download

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Cool NUCLEUS 3D Medical Animation

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