Tibia, Fibula and Patella Flashcards
Tibia general
- Second longest, second strongest bone in the body
- Longer than the fibula
- Differences by sex: males are nearly vertical while females have the distal end located more medial (a little bow-legged)
- Inferior surface is called the tibial plafond
Proximal tibia
- Superior surface is called the tibial plateau
- Greatly enlarged
- Tibial plateau is oval shaped (wider side-to-side) and contains medial and lateral condyles (flattened)
- Central portion of condyles articulate with femoral condyles
- Medial and lateral menisci overly peripheral portions (outer portions) of the condyles
Medial condyle
- Larger, with larger articular surface
- Medial surface is roughened for attachment of the tibial (medial) collateral ligament
Non articular intercondylar ridge
- Located between condyles
- Not part of the articular surface of the knee joint
- Located between medial and lateral condyles
- Contains 3 structures
3 structures of the intercondylar ridge
- Anterior intercondylar fossa (contains 3 “anterior” structure attachments)
- Intercondylar eminence
- Posterior intercondylar fossa (contains 3 “posterior” structure attachments)
Hand trick to remember what is attached where
- Hold hands in two C’s
- The right hand is medial, left hand is lateral
- The fingers are posterior, thumbs are anterior
- The right hand (medial) is the “big C” and the left hand (lateral) is the “little C”
- Touch your fingers together (posterior)
- Hold your thumbs apart (anterior)
Order of attachments from posterior to anterior
- PCL
- Posterior horn of medial meniscus
- Posterior horn of lateral meniscus
- Anterior horn of lateral meniscus
- ACL
- Anterior horn of medial meniscus
Intercondylar eminence
- Located between the anterior and posterior fossas
- Consists of a bony ridge with 2 tubercles (medial and alteral intercondylar tubercles)
- Covered with articular cartilage that is continuous with the tibial condyles
Tibial tuberosity
- Triangular prominence of bone with the apex directed inferiorly
- Attachment site of the patellar ligament is a continuation of quadratus femoris tendon
- Palpable
Fibular facet
Facet closest to the face (the inferior articulation is considered fibular notch)
- Oval shaped
- Posterolateral depression on the lateral tibial condyle
- Proximal articulation to the tibia and fibula (tib-fib joint)
3 borders of the shaft of the tibial
- Anterior
- Medial
- Lateral
Anterior border of shaft of tibia
- “Shin” is subcutaneous and palpable
- Rotates medially to become the anterior border of medial malleolus (starts at tibial tuberosity)
- This is the attachment site for crural fascia (deep fascia of the leg)
Medial border of shaft of tibia
- Extends from below the medial condyle and rotates medially to become the posterior border of the medial malleolus
- This is the attachment site for 4 structures
4 structures that attach to medial border of tibia
- Medial collateral ligament
- Popliteus muscle
- Soleus muscle
- Flexor digitorum longus
Lateral border of shaft of tibia
- AKA “interosseous crest”
- Extends from articular fibular facet, divides into anterior and posterior borders of fibular notch inferiorly
- Attachment site for posterior (inferior) tibiofibular ligament
3 surfaces of shaft of tibia
- Medial
- Lateral
- Posterior
Medial surface of shaft of tibia
- Smooth, convex
- Located between anterior and medial borders
- 3 muscles attach superiorly and have a common aponeurosis (pes anserinus)
- Pes anserinus = SGT (say grace before tea)
- S = sartorius
- G = gracilis
- T = semitendinosus
- Also, there is a roughened area superiorly for attachment of the tibial collateral ligament
- Inferiorly, the medial surface is subcutaneous and the crural fascial attaches along the medial surface of teh tibial shaft
Lateral surface of shaft of tibia
- Narrow surface with just one muscle attachment - tibialis anterior
- Tibialis anterior attaches on the upper 1/2 to 2/3
- Lateral surface is grooved by this muscle origin
- There are 4 tendons which cover the distal portion (medial to lateral)
- These include tibialis anterior, extensor hallucis longus, extensor digitorum longus, peroneus tertius
Posterior surface of shaft of tibia
- The soleal line is an oblique ridge from superolateral to inferomedial and is a partial origin of the soleus muscle
- The vertical line extends inferior from the soleal line
Muscle attachments in relation to vertical line on posterior surface of shaft of tibia
Lateral to vertical line
- Tibialis posterior (partial origin)
- Nutrient foramen
Medial to vertical line
- Flexor digitorum longus
Distal portion of posterior surface of shaft of tibia
- Smooth
- Covered by tendons (flexor digitorum longus, tibialis posterior, flexor hallucis longus)
NOTE: FDL is medial, TP is deep, FHL is lateral
Position of tendons at distal portion of tibial
REMEMBER
- At the distal portion of the psoterior surface of the tibia, the FDL and FHL are in opposite positions of what you would think
- Hallucis is more lateral, digitorum is more medial
- They cross at the heel
(anterior) Tom, Dick, Very Nervous Harry (posterior)
Nutrient foramen of tibial
- Blood supply from a branch of the posterior tibial artery
- Located just distal to the soleal line and lateral to the vertical line
- Points directly away from the growing end of the tibia (which is the proximal end)
- LARGEST nutrient foramina
Distal tibia
- Larger than shaft, smaller than proximal part
- 5 surfaces: anterior, posterior, lateral, medial, inferior
Anterior distal tibia
- Continuous with the lateral surface of the shaft of the tibia
- Distal portion contains a transverse groove for attachment of the ankle joint capsule
- Smooth except for this attachment site
Posterior distal tibia
- Continuous with posterior surface of shaft
- Continuous with posterior aspect of medial malleolus
- Grooves for 2 tendons are present here: tibialis posterior (deep to FDL) and flexor hallucis longus
Lateral distal tibia
- Fibular NOTCH (not facet) for articulation with fibula
- Attachment of 2 ligaments along margins (anterior tibiofibular ligament and posterior tibiofibular ligament)
Medial surface of distal tibia
Continuous with medial malleolus
Inferior surface of tibia
- AKA tibial plafond
- Quadrilateral shaped
- Wider anteriorly
- Concave anteroposteriorly
- Convex side to side
Medial malleolus
- Pyramidal shaped
- Extends inferiorly beyond rest of tibia
- Lateral surface articulates with talus
- Comma shaped facet for talar articulation
- Lateral surface is continuous superiorly with the tibial plafond
- Medial surface is subcutaneously palpable
Inferior surface of medial malleolus
- Inferior surface has 2 slight elevations (“hills”)
- These are the anterior and posterior colliculi
- The deltoid ligament attaches to both of these colliculi as well as the intercollicular sulcus, anterior border of medial malleolus, posterior border of medial malleolus