Case 3: Daniel Gatto

Joints

Connection between bones

Joint Types

Synovial

Cartilaginous

Fibrous

Synovial Joints

Freely movable (diarthrosis)

Connected by intraarticular space with articular cavity

• Contain synovial fluid = Reduce friction

Synovial Joints: Bone Articulation

Articular Head: Convex bone end moving in socket joint

Socket Joint: Concave bone end containing articular head

Synovial Joints: Joint Capsule

Surround joint

Fibrous Membrane: Dense connective tissue

Synovial Membrane: Synovial cells (synoviocytes)

• Type A: Macrophage-like cells remove debris

• Type B: Fibroblast-like cells produce glycoproteins → Synovial fluid

Synovial Joint Types

Ball and socket

• Acetabulofemoral

• Glenohumeral

Condyloid

Saddle

Hinge

Pivot

Modified hinge

Plane

• Patellofemoral

Cartilaginous Joints

Slightly movable (amphiarthrosis)

Connected by cartilage

Ex:

• Tibiofibular

• Carpus

• Tarsus

Fibrous Joints

Fixed (synarthrosis)

Connected by connective tissue (usually collagen)

Ex:

• Skull sutures

• Between ulna + radius

• Between tibia + fibula

Joint Menisci

Fibrocartilaginous discs in joints

Absorb force + prevent abnormal movement

In:

• Knee

• Wrist

• Acromioclavicular

• Sternoclavicular

• Temporomandibular

Joint Cruciate Ligaments

Ligaments crossing in X shape

In knee only

Joint Collateral Ligaments

Ligaments on side of joint

In many joints

Knee: Description

Synovial hinge joint

2 articulations

• Tibiofemoral: Between tibia + femur

• Patellofemoral: Between femur + patella

Knee: Movements

Flexion/extension

External/internal rotation

Knee: Bones

Femur: Superior

Tibia: Inferior

• Fibula: Not part of knee joint

Patella: Kneecap

Knee: Menisci

Medial: On medial tibia

• C-shaped

• Attached to MCL

Lateral: On lateral tibia

• Circular

Knee: Ligaments

Cruciate:

• Anterior (ACL)

• Posterior (PCL)

Collateral:

• Medial (MCL)

• Lateral (LCL)

Popliteofibular (popliteal)

Transverse

Anterolateral

Knee Cruciate Ligament: ACL

Anterior tibia → Lateral femur

Prevent anterior tibia/femur displacement

Prevent hyperextension

Knee Cruciate Ligament: PCL

Posterior tibia → Medial femur

Thicker than ACL

Prevent posterior tibia/femur displacement

Prevent hyperflexion

Knee Collateral Ligament: MCL

Medial femur → Medial tibia

Prevent medial tibia/femur displacement

Limit abduction

Knee Collateral Ligament: LCL

Lateral femur → Fibula head

Prevent lateral tibia/femur displacement

Limit extension + adduction

Knee Popliteofibular Ligament

Popliteus tendon → Fibula head

Stabilize posterolateral knee

Knee Transverse Ligament

Between menisci

Stabilize + decrease pressure on menisci

Knee Anterolateral Ligament

Lateral femur → Tibia

Stabilize tibia during internal rotation

Knee: Tendons

Quadriceps femoris tendon: Superior

• Connect 4 quad muscles to patella

Patellar tendon/ligament: Inferior

• Connect patella to tibia

Popliteus tendon: Posterolateral

Biceps femoris tendon: Lateral

Pes anserinus tendon: Medial

Knee: Bursae

Decrease friction between muscles, tendons, and bones

Elbow: Description

3 synovial hinge joints

1. Humeroulnar: Between humerus + ulna

2. Humeroradial: Between humerus + radius

3. Proximal radioulnar: Between radius + ulna

Elbow: Movements

Flexion/extension

Pronation/supination (radioulnar joint)

Elbow: Bones

Humerus: Superior

Ulna + Radius: Inferior

Elbow: Ligaments

Collateral:

• Ulnar

• Radial

Annular

Elbow: Ulnar Collateral Ligament

Medial humerus → Ulna + annular ligament

(Medial ligament)

Elbow: Radial Collateral Ligament

Lateral humerus → Ulna + olecranon

(Lateral ligament)

Elbow: Annular Ligament

Around radius head (radioulnar joint)

Anchor radius head to ulna radial notch

Elbow: Tendons

Anterior:

• Biceps tendon

• Brachialis tendon

Posterior: Triceps tendon

Medial: Common flexor tendon

Lateral: Common extensor tendon

Wrist: Description

4 joint types

1. Radiocarpal: Synovial ellipsoid

• Between radius + proximal carpal bones (not pisiform)

2. Midcarpal: Synovial

• Between proximal + distal carpal bones

3. Intercarpal: Amphiarthroses

• Between carpal bones

3. Carpometacarpal (CMC)

• 2nd-5th: Amphiarthroses

  • Between carpal + metacarpal bones

• Thumb: Synovial saddle

  • Between trapezium + 1st metacarpal bone

Wrist: Movements

Flexion/extension

Abduction/adduction

Thumb CMC: Opposition + circumduction

Wrist: Bones

8 carpals

2 rows: Lateral to medial (Some Lovers Try Positions That They Can’t Handle)

• Proximal:

  • Scaphoid (deep to anatomical snuff box)

  • Lunate

  • Triquetrum

  • Pisiform

• Distal:

  • Trapezium

  • Trapezoid

  • Capitate

  • Hamate

Wrist: Ligaments

Collateral:

• Ulnar

• Radial

Retinaculum:

• Flexor (Transverse Carpal Ligament)

• Extensor (Dorsal Carpal Ligament)

Radiocarpal:

• Palmar

• Dorsal

Wrist: Ulnar Collateral Ligament

Ulna → Triquetrum

Medial wrist stability

Wrist: Radial Collateral Ligament

Radius → Scaphoid

Lateral wrist stability

Wrist: Flexor Retinaculum

Pisiform + hamate (medial carpals) → Scaphoid + trapezium (lateral carpals)

Anchor flexor tendons (palmar)

Roof of carpal tunnel

Wrist: Extensor Retinaculum

Pisiform + triquetrum → Radius

Anchor extensor tendons (dorsal)

Wrist: Radiocarpal Ligaments

Stabilize wrist + constrain carpal bone motion

Palmar: Radius → Lunate + capitate

Dorsal: Distal radius → Dorsal carpal bones

Wrist: Tendons

Flexor Tendons: Palmar

Extensor Tendons: Dorsal

Wrist: Channels

Carpal tunnel

Ulnar/guyon canal

Wrist: Carpal Tunnel

Passage for:

• Median n.

• Tendons

  • Flexor pollicis longus

  • Flexor digitorum profundus

  • Flexor digitorum superficialis

Borders:

• Medial: Pisiform + hamate

• Lateral: Scaphoid + trapezium

• Superior: Flexor retinaculum

• Inferior: Carpal groove (between carpal bones)

Wrist: Guyon Canal

Passage for ulnar nerve + artery

Borders:

• Medial: Pisiform

• Lateral: Hamate

• Superior: Palmar carpal ligament

• Inferior: Flexor retinaculum + hypothenar muscles

Finger Joints: Description

3 synovial joints

Metacarpophalangeal (MCP): Between metacarpals + proximal phalanges

Interphalangeal (IP):

• Proximal (PIP): Between proximal + middle phalanges

• Distal (DIP): Between middle + distal phalanges

Finger Joint: Movements

Flexion/extension

MCP: Abduction/adduction

Finger Joint: Ligaments

Collateral

Volar plate

Finger Joint: Collateral Ligaments

Surround + stabilize joints

Finger Joint: Volar Plate

Fibrocartilaginous structure on palm side of each joint

Prevent hyperextension

Knee Joint Lesions: Description

Meniscus Tear: Rupture/tear to meniscus

Cruciate Tear: ACL/PCL injury

Collateral Tear: MCL/LCL injury

Patellofemoral Pain Syndrome (PFPS): Pain behind/around patella aggravated by weight-bearing activities (squatting, running, climbing stairs)

Meniscus Tear: Pathogenesis

Traumatic: Excess external force (twisting/pivoting planted foot or hard landing) = Damage meniscus

Degenerative: Overuse/chronic stress = Damage meniscus

Cruciate Tear: Pathogenesis

ACL: Knee extension + valgus force (foot out, knee in)

• Usually non-contact injury

PCL: Knee hyperflexion + excess force on foot = Drive tibia posterior

• Usually contact injury

Collateral Tear: Pathogenesis

MCL: Force on outer knee = Valgus force + external rotation

LCL: Force on inner knee = Varus force (foot in, knee out) + internal rotation

PFPS: Pathogenesis

Muscle/tendon weakness = Abnormal patella tracking over femur condyles = Overload patellofemoral joint = Pain

Knee Joint Lesions: Investigations

Trauma vs no trauma

Physical exam

Imaging

Knee Joint Lesion Investigations: Physical Exam

Meniscus Tear:

• Thessaly test

• McMurray’s test

• Apley’s test

Cruciate Tear:

• ACL

  • Lachman test

  • Anterior drawer test

  • Pivot shift test

• PCL

  • Posterior drawer test

  • Posterior sag test

  • Quadriceps active test

Collateral Tear:

• MCL: Valgus stress test

• LCL: Varus stress test

PFPS:

• Clarke test

• Patellar apprehension/displacement test

• Patellar tilt test

Knee Joint Lesion Investigations: Imaging

XR:

• Ottawa Criteria: Needed if 1 of…

  • ≥ 55 years

  • Patella/fibula head tenderness

  • Flexion < 90º

  • Cannot bear weight

US:

• Effusions

• Assess bursa

CT:

• Fractures

• Trauma

MRI

Knee Joint Lesions: Management

Conservative

Surgery

Knee Joint Lesions: Conservative Management

Initial management

Rest

Ice

Elevate

NSAIDs

Knee brace

Physical therapy + strength training

Knee Joint Lesions Management: Surgery

Meniscus Tear:

• Indication: Complex traumatic tear

• Contraindication: Degenerative tear

• Method:

  • Repair/reconstruct meniscus

  • Partial menisectomy

Cruciate/Collateral Tear:

• Indication:

  • Recurrent tears

  • Dysfunction (lax knee)

• Methods:

  • Reconstruction: Graft from tissue

  • Repair: Suture torn ligament to bone

PFPS: Management

POLICE principles

• P: Protection (rest)

• OL: Optimal loading

  • Physical therapy + strength training

  • Low-impact activities

• I: Ice

• C: Compression

• E: Elevation