A joint is the location at which A joint is the location at which bones connect. They are bones connect. They are constructed to allow movement constructed to allow movement (except for skull bones) and (except for skull bones) and provide mechanical support, and provide mechanical support, and are classified structurally and are classified structurally and functionallyfunctionally

Structural classification :Structural classification :

fibrous jointfibrous joint

cartilaginous jointcartilaginous joint

synovial jointsynovial joint

Functional classification:Functional classification:

SynarthrosisSynarthrosis

Amphiarthrosis Amphiarthrosis

diarthrosisdiarthrosis

Bones of the lower limb:Bones of the lower limb:

Hip boneHip bone

PatellaPatellaFemurFemur

Tibia & FibulaTibia & FibulaThe FootThe Foot

the hip bone:the hip bone:

• At birth 3 separate bones that fuse at puberty.

• Ilium• Ischium• Pubis

Ischium

Ilium

Pubis

Acetabulum

Acetabular Notch

The Femur (ant. view)The Femur (ant. view)

Head

Neck

Greater

& Lesser Trochanters

Intertrochanteric Line

The Femur (post. view)The Femur (post. view)

1. Intertrochanteric Crest

2. Quadrate Tubercle

3. Gluteal Tuberosity

4. Pectineal Line

Approx. 125o

•The angle of inclination is measured in the frontal plane and typically ranges from 115 to 140 degrees.

Coxa VaraCoxa Vara • An angle between femoral neck and shaft less than 115°; increases stress on femoral neck.

• This:1. shortens the limb;2. decreases the

effectiveness of the abductors;

3. increases the load on the femoral neck;

4. reduces the load on the femoral head.

Coxa ValgaCoxa Valga • An angle between femoral neck and shaft greater than 140°; increases pressure into the joint

• This:

1. lengthens the limb;

2. mimics contracture of the hip abductors;

3. reduces the load on the femoral neck;

4. increases the load on the femoral head.

Type: Type:

Synovial Ball-and-Socket JointSynovial Ball-and-Socket Joint

Type: Type:

Synovial Ball-and-Socket JointSynovial Ball-and-Socket Joint

Articular Surfaces :Articular Surfaces :

Femoral head and Acetabulum

The femoral head and acetabulum have large amounts of spongy, trabecular bone to help attenuate forces applied to joint.

Approx. 70% of the femoral head articulates with the acetabulum

only only horseshoe horseshoe shaped lunate shaped lunate artic. surface artic. surface is covered by is covered by articular articular cartilage.cartilage.

Fibrous Capsule:Fibrous Capsule: Proximally - 5-6 mm. Medial to Proximally - 5-6 mm. Medial to acetabulumacetabulum

Distally – Distally – AntAnt. Intertrochanteric . Intertrochanteric line; line; PostPost. Halfway along femoral . Halfway along femoral neckneck

Transverse Acetabular Lig.Ligament of the

Head of the Femur (Lig. Teres)

Ligament NameLocationMain Function *

Iliofemoral “Y”Ant. Surf. CapsulePrevents hyperextension during standing

PubofemoralAnt. & Inf. Surf. Cap.

Limits abduction and extension

IschiofemoralPosterior Surf. Capsule

Prevents hyperextension

Lig. of HeadIntracapsular - betw. fem. head and acetab. notch

Weak, contains artery, may limit

adduction

Transverse Acetab.

Continuation of acetab. labrum over notch

Helps hold head in acetabular fossa

*note: no ligaments limit hip flexion

(psoas bursa).

Med. & Lat. Fem. Circumflex a.

Acetabular a.

Acetabular

pierce capsule at femoral attachment and proceed along femoral neck toward head beneath synovial

membrane.

Motion of the Hip Joint

Extension

Hyperextension

Flexion Abduction

Adduction

Motion of the Hip Joint cont.

Medial Rotation Lateral Rotation

- The Knee Joint is the largest & most complicated joint in the body .

- It consists of 3 Joints within a single synovial cavity :

Medial Condylar Joint : Between the medial condyle “of the femur” & the medial condyle “of the tibia” .

Latral Condylar Joint : Between the lateral condyle “of the femur” & the lateral condyle “of the tibia” .

Patellofemoral Joint : Between the patella & the patellar surface of the femur .

- The fibula is NOT directly involved in the joint .

1 Capsule : Surrounds the sides & posterior aspect of the joint… On the frontal side , the capsule is

absent.

On each side of the patella , the capsule is strengthened by the tendons of Vastus Lateralis & Vastus Medialis .

communicates with:

- suprapatellar bursa, - popliteus bursa, - semimembranosus burse, - gastrocnemius bursa.

Bursae related to the knee joint:1 -Anterior to the knee:

1 .supra-patellar bursa 2 .prepatellar bursa

3 .superficial infra-patellar bursa 4 .deep infrapatellar bursa

2 -Posterior to the knee: 1 .popliteus bursa

2 .semimembrenosus bursa 3 .semitendinosus bursa

4 .gastrocnemius bursa 5 .gracilis bursa 6 .biceps bursa

7 .sartorius bursa

2) Ligaments : Extracapsular Ligaments : - Ligamentum Patellea ((a continuation of the

Quariceps Femoris muscle ))

- Lateral Collateral Lig. - Medial Collateral Lig. - Oblique Popliteal Lig(( derived from the

Semimembranosus muscle )).

Structures inside the knee jointStructures inside the knee joint::

The medial and lateral menisci are 2 C-shaped sheets of fibrocartilage between the tibial & femoral condyles

- Their peripheral border is thick & attached to the capsule ,

their inner border is thin & forms a free edge .

- Each meniscus is attached to the upper surface of the tibia by anterior & posterior horns .

Intracapsular Ligaments : Cruciate Ligaments : 2 strong ligaments that cross each

other within the joint cavity .

Anterior Cruciate Ligament (ACL) :

• Attached to the anterior intercondylar area of the tibia , passes upward , backward & laterally to get attached to the lateral femoral condyle .

• Prevents posterior displacement of the femur (( With the knee joint flexed , the ACL prevents the tibia from being pulled anteriorly)) .

Posterior Cruciate Ligament (PCL) : •Attached to the posterior intercondylar area of the tibia , passes upward , forward , & medially to get attached to the medial femoral condyle .

•Prevents anterior displacement of the femur (( With the knee joint flexed , the PCL prevents the tibia from being pulled posteriorly )) .

Thick, circular-triangular bone which articulates with the femur and covers and protects the anterior articular surface of the knee joint.

It is the largest sesamoid bone .

Anterior surfaceIt can be divided into three parts:

The upper third is coarse, flattened, and rough; it serves for the attachment of the tendon of the quadriceps and often has exostoses.

The middle third has numerous vascular canaliculi.

The lower third includes the distal apex which serves as the origin of the patellar ligament.

Posterior surfaceThe upper three-quarters

articulates with the femur and is subdivided into a medial and a lateral facet by a vertical ledge which varies in shape.

It is attached to the tendon of the quadriceps femoris muscle, which contracts to extend/straighten the knee. The vastus intermedialis muscle is attached to the base of patella. The vastus lateralis and vastus medialis are attached to lateral and medial borders of patella respectively.

gliding joint, between the patella and the patellar surface of the femur

the fibula is not directly involved in the joint.

Popliteal Fossadiamond-shaped intermuscular space situated at the back of the knee.The fossa contains

the popliteal vessels,

the small saphenous vein,

the common peroneal and tibial nerves,

the posterior cutaneous nerve of the thigh,

the genicular branch of the obturator nerve,

connective tissue, and lymph nodes.

Boundaries

•Laterally: The biceps femoris above and the lateral head of the gastrocnemius and plantaris below

•Medially: The semimembranosus and semitendinosus above and the medial head of the gastrocnemius below

Proximal Tibiofibular JointArticulation is between the lateral condyle of the tibia and the head of the fibula.The articular surfaces are flattened and covered by hyaline cartilage.This is a synovial, plane, gliding joint.

LigamentsAnterior and posterior ligaments strengthen the capsule. The interosseous membrane Capsule and Synovial Membrane attached to the line of the articular surface.

The common peroneal nerve supplies the joint.Movements

A small amount of gliding movement takes place during movements at the ankle joint.

Distal Tibiofibular Joint

ArticulationArticulation is between the fibular notch at the lower end of the tibia and the lower end of the fibula.

TypeThe distal tibiofibular joint is a fibrous joint.

CapsuleThere is no capsule

Ankle Joint

The ankle joint consists of a deep socket formed by the lower ends of the tibia and fibula, into which is fitted the upper part of the body of the talus.

ArticulationArticulation is between the lower end of the tibia, the two malleoli, and the body of the talus.

TypeThe ankle is a synovial hinge joint.

CapsuleThe capsule encloses the joint and is attached to the bones near their articular margins.

LigamentsThe medial, or deltoid, ligament

The lateral ligament is weaker than the medial ligament and consists of three bands.

The anterior talofibular ligament

The calcaneofibular ligament The posterior talofibular ligament

Synovial MembraneThe synovial membrane lines the capsule.

Nerve SupplyDeep peroneal and tibial nerves supply the

ankle joint.

Synovial MembraneThe synovial membrane lines the capsule.

Nerve SupplyDeep peroneal and tibial nerves supply the ankle joint.

MovementsDorsiflexion (toes pointing upward) and plantar flexion (toes pointing downward) are possible. The movements of inversion and eversion take place at the tarsal joints and not at the ankle joint.