END OF SEM ANATOMY MASTER REVISION

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1 CONTENTS: END OF SEM ANATOMY MASTER REVISION 1. KNEE & LEGS 2. ANKLE & FOOT 3. VERTEBRAL COLUMN 4. CERVICAL SPINE 5. THORACOLUMBAR SPINE & PELVIS 6. DIAPHRAGM, PELVIC FLOOR & ABDOMINALS KNEE KNEE JOINT COMPLEX TIBIOFEMORAL Joint (femoral condyles + tibial plateau) Hinge Joint = Predominantly Uniaxial (limited rotation) Great Stability in E w/ Screw Home Mechanism F/E along Sagittal Plane on Coronal Axis Mobility in F (allow foot clearance & optimal orientation of foot) Poor degree of interlocking joint surfaces (dependent on active & passive structures such as ligaments, menisci & muscles) Large Lever Arms (therefore, predisposed to injury due to long bones) Femoral Articular Surface > Tibial Articular Surface (due to differences in condyle size) *5 o of HE is critically important for knee function *Can t rotate tibia & fibula voluntarily *Recurvatum = hyperextension of kneecap Knee Alignment Q Angle (between axis of tibia & femur): Measured along ASIS Patella (centre)/ Tibial Tuberosity 14 o = Men 17 o = Women 5 o Genu Valgus: Tibia is laterally inclined in relation to femur; medial fem condyle extends slightly more distally. Alignment of the femoral condyles on the transverse plane determine the orientation of the F/ E axis of Knee Mechanical Axis of Lower Limb = 2-3 o Varus (tibial midline HOF) Shortens width of Base of Support to for better weight-bearing & gait Knee Tendon Attachment Semimembranosus Tendon attaches posteriorly to Tibial Medial Condyle, superior to Popliteus Sartorius, Gracilis & Semitendinosus (Medial Lateral) Oblique Popliteal Ligament blends in with Posterior Capsule Synovial Membrane Synovial surfaces surround all articular areas, capsule surrounds the entirety of joint An intracapsular extrasynovial space exists between menisci 1

2 Actively supported by: 1) Quad attachments 2) laterally by ITB 3) medially by Tibial Collateral Ligament 4) posteriorly reinforced by Oblique Popliteal ligament (restricts HE) 5) posterolaterally (pierced by popliteus) Tibial Meniscal Discs Circular fibrocartilage pieces that articular contact & congruency, compression stress & protect articular cartilage After total meniscectomy, contact areas ~75% & peak local contact stress ~235% Medial Menisci (MM) AP length w/ thicker posterior horn (as the primary coverage over tibial plateau, it bears a large portion of the articular stress). Thus, the Screw Home Mechanism IR to the MM during Knee E for weight-bearing LM are narrower, more mobile compared to MM which is anchored to TCL SCREW HOME Mechanism Tibiofemoral Joint initiates screw home mechanism by slightly rotates during a primary action to tighten its ligaments (especially ACL & PCL) for stability, a contact area w/ MM Flexion + LR Extension + MR 20 o F 0 o E In terminal extension, this mechanism locks up the knee for greater stability, apart from tightening ligaments, interlocking between the joints If tibia is not fixed on the floor, it will LR for the screw home mechanism, if foot is fixed on the ground it will then femur will MR after posteriorly sliding Popliteus locks TFJ w/ femur IR, to unlock the extended leg it must ER femur during F Femoral/Tibial Gliding During movement, the kneecap has two directions of movement, sliding (AP) & rolling (of either the tibia or femur), both directions will not happen purely but in conjunction *ACL/PCL tightens during flexion or gliding, pulling femur back into a slide backwards or forwards For tibial extension, tibia will slide & roll anteriorly For femoral extension, it will slide backwards but still roll anteriorly To prevent excessive knee F, the ACL will tighten, forcing the femur into an anterior slide PATELLOFEMORAL Joint Patellar glides upon Patella Groove on the Femur Leverage of Quads by altering its LOA & distance from axis (thus moment arm). Net pull towards HOF (in a slightly valgus direction) Provides protection to the exposed cartilage of femoral condyles in Knee F Distributes forces & pressure placed on the femur Friction of Quads Tendon as it will rub upon the fem condyles w/o Patella Patella is most inclined to dislocate laterally even w/ the VMO s medial pull resistance and the greater height of the lateral portion of the Patella Groove Patellectomy = Quads Moment Arm, Knee ROM, Anterior Instability & Loss of Trochlea Protection Patella glides distally permitted by the unfolding of the Suprapatellar Pouch Translations Glides distally on femur during Knee F 2

3 Glides medially during 0-30 o F then lateral during o F Rotations Laterally tilts during flexion Contact Area w/ increasing knee flexion, the patella moves proximally to contact area Patella Bursae & Spaces Bursae Suprapatellar Subcutaneous Prepatellar Subcutaneous Infrapatellar Deep Infrapatellar Infrapatellar Fat Semimembranosus Subsartorial (pes anserinus) Location Above patellar, deep to the patellar tendon Superficial to patellar Superficial to patellar tendon, below patellar Inferior to patellar, deep to patellar tendon Deep to Infrapatellar bursae Behind femorotibial joint On medial side of the tibia Fat Pad separates Quads Tendon from Femur ( moment arm) Articular Genus pulls Suprapatellar Bursae back from being pinched during Knee E Bursae promotes frictionless Knee movement, but pain sensitive and susceptible to inflammation Knee Movement Range Motion Range o Gait: o o Stairs: >110 o o Sitting: 93 o o Shoe Tying: 106 o Loading o Level Ground: 3x BW o Stairs: 4.25x BW Movement Range Flexion 140 o Hyperextension 5 o Accessory Movements AP Glide Medial/ Lateral Rotation Medial/ Lateral (Transverse) Glide ABD/ADD Superior Tibiofibular Joint Arthrodial (Plane) Joint 3

4 KNEE MUSCLE COMPLEMENT Action Muscles Extension Quads Flexion Hamstrings (weak contribution from gastro, soleus & sartorius) Internal Rotation Semitendinosus, Semimembranosus, Popliteus, Gracilis & Sartorius External Rotation Biceps Femoris & TFL *popliteus unlocks knee from screw mechanism as well as assisting the PCL w/ resisting anterior gliding Muscle Origin Insertion Innervation Function Anterior Compartment (Knee E) Rectus Femoris (deep to satorius) Vastus Medialis Vastus Intermedius (deep to RF) Vastus Lateralis AIIS Medial Lip of Linea Aspera & Intertrochanteric Line Anterior surface of femur Greater Trochanter & Lateral Lip of Linea Aspera Patellar via Quadriceps Tendon Femoral N (L2-4) Sartorius ASIS Pes Anserinus Femoral N (L2-3) Medial Compartment (Adduction) Adductor Longus (anterior) Adductor Brevis (superior) Adductor Magnus (posterior, largest) Gracilis Pectineus Superior Ramus of Pubis Pectineal Line & Inferior Pubic Ramus Inferior Ramus & Ischiopubic Ramus & Ischial Tuberosity Inferior Pubic Ramus & Pubic Symphysis Pecten Pubis (like superior pubic ramus) Posterior Compartment (Knee Flexion) Biceps Femoris *Long Head (left) *Short Head (right) Semitendinosus (lateral, more posterior to semimembranosus) Semimembranosus Long: Ischial Tuberosity Short: Lateral Lip of Linea Aspera Ischial Tuberosity *posterior thigh muscles are biarticular (crosses two joints) KNEE LIGAMENT STRUCTURES Linea Aspera Linea Aspera & Adductor Tubercle Obturator N (L2-4) Obturator N (L2-4) & Tibial N (L4) Knee E Hip F Knee E Hip F, ADD & LR Knee MR Hip ADD & F (Hip E 90 o F) Pes Anserinus Obturator N (L2-3) Hip ADD Pectineal Line Head of Fibula & Lateral Condyle of Tibia Pes Anserinus Medial Condyle of Tibia Femoral N (L2-3) & Obturator N (L3-4) Tibial N (L5-S2) Hip ADD, F & MR Knee F & LR Hip E (long head only) *Tibial ER Knee F & MR Hip E *Tibial IR Ligament Attachments Resists Anterior Cruciate Ligament (ACL) Anterior Tibial Head Posteriorly Posterolateral Band (PLB): largest, tightest in E below Lateral Menisci Anteromedial Band (AMB): tightens in F Posterior Cruciate Ligament Posterior Tibial Head > Anteriorly (PCL) below Medial Menisci Anterior Gliding (during Tibial/ Femoral E) Medial Femoral Condyle Midline of Superficial (longer): Valgus Force (throughout Tibial (medial) Collateral Ligament Medial Tibia F) (TCL) Medial Femoral Condyle Posterior Edge of Medial Tibial Condyle Deep (shorter): Anterior Displacement of Tibia Anterolateral Ligament (ALL) Posterior Edge of Lateral Condyle Lateral Head of Tibia Tibial 30 o F + Anterolateral Stability Fibular (lateral) Collateral Ligament Posterior Edge of Lateral Condyle (FCL) Head of Fibula Varus Force 4

5 Posterior Tibiofibular Ligament (PTL) Inferior Posterior Tibia Fibula Stability of TFJ Oblique Popliteal Ligament (OPL) Lateral Femoral Epicondyle Medial Tibial Condyle Knee HE Transverse Ligament Connects Anterior Lateral & Medial Menisci Coronary Ligaments Inferior edges of LM & MM Knee Capsule Posterior Meniscofemoral Posterior Horn of LM Femur??? *TCL tends to be part of capsule while the FCL is more prominently outside the capsule Anterior Gliding of Anterior Menisci Horns (as they are somewhat mobile & being pinched by the femur OR tibia) Anchors four points onto the tibia ANTERIOR CRUCIATE LIGAMENT Resists anterior translation of tibia on femur Resists posterior translation of femur on tibia rotation stability Resists valgus forces terminal E (but not main restraint) 10 o IR & 30 o ER Injury Large valgus moment that creates excessive knee ABD & tibial ER Commonly caused by pivoting sports w/ females being 3-5x more likely to suffer from this injury ACL Deficiency Test: Lachman s Test 15 o knee F) & Anterior Drawer Test (@ 90 o knee F) done by gliding the tibia in an AP manner, lack of resistance = compromised ACL POSTERIOR CRUCIATE LIGAMENT Resists posterior translation of tibia on femur Resists anterior translation of femur on tibia Injury Throw against dashboard during car crash Hyperflexion or HE PCL Deficiency Test: Sag Test by placing the 90 o F, if there is a deficiency than the knee should have a slight backwards bend to it (meaning that the tibia is gliding posteriorly & the femur is anterior translating) 5

6 ANKLE ANKLE JOINT COMPLEX Stability & Mobility Demands Support of Entire Body Weight Control of Leg & Stabilisation over Foot Adjustment over irregular surfaces Elevation of Body Shock Absorption *function is dependent upon 3 intrinsic foot arches, ligament support & dynamic muscle contractions 3 Axes of Movement Dorsiflexion (30 0 )/ Plantarflexion ( ) only talocrucial joint (sagittal plane) ABD/ADD forefoot (transverse plane) Inversion/Eversion (40 o total ROM, may be more on one side than other) happens at subtalar joint (on coronal plane) Pronation (DF + Eversion + ABD)/ Supination (PF + Inversion + ADD) (triplanar movement, requires all three joints) Close-Packed Positions Ankle DF (end feel is firm) Tarsal Joints full inversion Metatarsophalangeal (MTP) extension Interphalangeal (IP) extension Force Transfer Largest distally & proximally, force transfer thru tibia Anterior Tibia under tension forces Posterior Tibia under compression forces 90% of Tibial Stress Fractures is located posteromedial o External Tibial Torsion Navicular Stress Fractures the central zone of force between the medial & intermediate cuneiform whereupon medial & lateral compressive forces are directed thru 1 st & 2 nd Ray, this can cause hypovascularity (lack of blood supply) FIBULA Muscle Attachment Talocrural Joint Stability Ligament Attachment *not a structural bone, only for the attachments of important active structures Regions of Foot Rearfoot (talus & calcaneal) Midfoot (navicular, cuboid, lateral, intermediate & medial cuneiform) Forefoot (phalanges) 1 st, 2 nd & 3 rd Ray: corresponding cuneiform w/ phalange 4 th & 5 th Ray: just 4 th & 5 th phalange *2 nd ray is least mobile while 1 st ray provides stable medial side for push-off during gait 6

7 Tendons 2 sesamoid bones in tendons of FHB under 1 st MTP prevents weightbearing from compressing the tendon & aligns tendon fibularis tendon sulcus on lateral calcaneus facilitates passing of the fibularis tendons DISTAL TIBIOFIBULAR Joint (DTFJ) Fibrous Syndesmosis Joint Stability of Distal Tibiofibular Joint is crucial for the stability of the Talocrural Joint Consists of: o Anterior Tibiofibular Ligament (ATL) o Posterior Tibiofibular Ligament (PTL) o Interosseous Membrane (IOM) TALOCRUCAL Joint Synovial Hinge Widest part of the talus firmly fits into the mortise (inverted cup formed by the tibia & fibular) in DF, if ER of the foot is experienced the talus s widest side is angled & jammed into the mortise, possibly causing separation of the distal fibula & tibia OR tearing anterior tibiofibular ligament OR fractures fibula OR fractures at the corners of the talar dome DF is the close-packed position of the talocrural joint, providing most stability In PF, the talus s narrow part is moved into the mortise SUBTALAR (Talocalcaneal) Joint (STJ) 3 articular facets between talus & calcaneus, vital for supination & pronation Translates movements of the foot to the leg, i.e. foot pronation = tibial IR Inclined ~45 o anterior to posterior, slightly medial to the long axis of the foot Transverse Tarsal Joint = Talonavicular & Calcaneocuboid forms joint between rearfoot & midfoot Calcaneocuboid Saddle Joint (Convex Debate between function Talonavicular Concave)/ Plane Joint of joint & its actual range Talocalcaneonavicular Ball & Socket Joint *rest are plane joint* Arches of the Foot - Medial Longitudinal Arch (stabilised by fibularis longus, abductor hallucis, TA & TP) - Lateral Longitudinal Arch (stabilised by fibularis brevis) - Transverse Arch *arches serve as shock absorbers & energy returners (during gait) *arches protect the blood vessels, neural & musculoskeletal structures underneath the foot during weight-bearing *the medial arch can be tested w/ the Navicular Drop Test, comparing the differences in height between the arch and the floor when load is placed on the foot Arch Medial Arch Lateral Arch Transverse Arch Muscular Support - TA, TP, FHL, FDL & Fibularis Longus, - Fibularis Longus & Brevis, FDL - Fibularis Longus, TP & Adductor Hallucis Plantar Aponeurosis, Long & Short Plantar Ligament + Spring Ligament (for medial arch) ANKLE MUSCLE COMPLEMENT Action Muscles Inversion TA/ TA Eversion FB & FL Dorsiflexion TA/ EHL & ED Plantarflexion Triceps Surae (Gastro, Soleus, Popliteus, Plantaris) 7

8 Muscle Origin Insertion Innervation Action Anterior Compartment (DF & Inversion) Tibialis Anterior Extensor Hallucis Longus Extensor Digitorum Longus Lateral Tibia Condyle Fibula & Interosseous Membrane Lateral Tibia Condyle + Interosseous Membrane Posterior Compartment (PF & Knee Flexion) Medial Cuneiform & 1 st MT Base of Distal Phalanx of 1 th Digit Distal Phalanges of 2 nd -5 th Digit Deep Fibular N (L4-5) Deep Fibular N (L5-S1) DF (agonist) Midfoot Inversion (contributes) Popliteus Lateral Femoral Condyle Posterior Tibia Tibial N (L4-S1) Knee MR & F Tibialis Posterior Gastrocnemius Soleus (deep to plantaris) Plantaris (deep to Gastrocnemius) Flexor Digitorum Longus Flexor Hallucis Longus Lateral Compartment (Eversion) Fibularis Brevis Fibularis Longus Intrinsic Foot (supports arches) Extensor Hallucis Brevis (medial to EDB) Extensor Digitorum Brevis Flexor Digitorum Brevis Flexor Hallucis Brevis Flexor Digiti Minimi Brevis Abductor Hallucis Adductor Hallucis Flexor Digiti Minimi Abductor Digiti Minimi (lateral to FDB) Lumbricals Posterior Interosseous Membrane Lateral & Medial Femoral Condyles Posterior Head of Fibula Posterior Lateral Femoral Condyle Posterior Tibia Interosseous Membrane & Posterior of Fibula Lateral Fibula Superolateral surface of Calcaneus Navicular Tuberosity, All Cuneiforms & 2 nd -4 th MT Calcaneal Tendon (Archimedes tendon) Plantar 2 nd -5 th DP Base of Distal 1 st Phalanx 5 th MT Tuberosity Base of 1 st MT (wraps underneath foot) Dorsal 1 st MTP Dorsal 2 nd -4 th PIP Tibial N (L4-5) Tibial N (S1-2) Tibial N (S2-3) Superficial Fibular N (L5-S2) Deep Fibular N (L5-S1) PF Inversion (agonist) & PF (slight contribution) PF (agonist) & Inversion (small contribution as it is aligned medially) (Knee F only for Gastro) PF (agonist) Eversion (agonists) PF (small contribution) 1 st Ray E 2 nd -4 th Ray E Calcaneal Tuberosity & Plantar Aponeurosis Plantar 2 nd -4 th MP 2 nd -5 th Ray F Plantar Cuboid, Lateral Cuneiform & medial 1st Plantar 1 st PP 1 Medial Plantar N Ray F MTT (S2-3) Base of 5 th MT 5 th PP 5 th Ray F Medial Calcaneal Tuberosity Oblique: Base of MT Transverse: 2 nd -4 th MTP Plantar 5th MMT Calcaneal Tuberosity & Plantar Aponeurosis Medial side of FDL Tendons Dorsal 1 st MTP Lateral Base of 1 st PP Plantar 5th MTP Medial side of MTP Lateral Plantar N (S2-3) Medial & Lateral Plantar N (S3) 1 st Ray ABD 1 st Ray ADD 5th Ray F 5th Ray ABD IP E while MTP F Assists FDL w/ F (also Calcaneal Tuberosity & Quadratus Plantae Tendon of FDL realigns angle of FDP Long Plantar Ligament pull) Lateral Plantar N Plantar Interossei Medial side of 3 rd -5 th MT Medial Side of 3 rd -5 th PP ADD 2 (S2-3) nd 4 th Ray Dorsal Interossei Between all MT Both sides of 2 nd PP, but only on lateral side of 3 rd & 4 th PP ABD 2 nd 4 th Ray 8

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10 ANKLE LIGAMENT STRUCTURES Ligament Attachments Resists Fibular Ligaments Anterior Tibiofibular Ligament (ATL) Distal Anterior Tibia Distal Anterior Fibula (consists of 2 separate superior & inferior bands) Separation & Stability of TFJ Distal Posterior Tibia Distal Posterior Posterior Tibiofibular Ligament (PTL) Fibula Interosseous Membrane (IOM) Within the Tibiofibular Joint Anterior Talofibular Ligament (ATFL) Lateral Posterior Lateral Talus Posterior Distal Fibula Posterior Talofibular Ligament (PTFL) Lateral Anterior Talus Anterior Distal TCJ Stability & Excessive Inversion Fibula Calcaneofibular Ligament (CFL) Lateral Calcaneus Apex of Fibula Intrinsic Ligaments Flexor Retinaculum Medial Malleolus Calcaneus Creates the Tarsal Tunnel, anchors flexor & TP tendons Talocalcaneal Interosseous Lateral Anterior Calcaneus Lateral Anterior Talus (w/ sinus tarsi) Talar Calcaneal Stability Dorsal Calcaneonavicular Dorsal Calcaneus Posterior Lateral Bifurcated Ligaments Navicular Calcaneus Navicular Stability Dorsal Calcaneocuboid Dorsal Calcaneus Cuboid (x3 bands) Calcaneus Cuboid Stability Cervical Ligament Calcaneus Talus (much like CFL but Resists Inversion & Stability of Calcaneus/ anterior) Talus Long Plantar Ligament Base of 4 th & 5 th MT Plantar Calcaneus Short Plantar Ligament Plantar Lateral Cuneiform Plantar Maintains Lateral Arch Calcaneus Plantar Calcaneonavicular (Spring) Ligament Plantar MTP Capsules Plantar Calcaneus (medial side) Stores energy during gait & releases energy as a spring during push-off phase 2x tensile strength of plantar ligaments, Plantar Fascia Plantar PIP Plantar Medial Calcaneal rich in proprioceptors, maintains rigid foot Tuberosity during step-off in gait (during MTP HE & PF pushes calcaneal tuberosity posteriorly Tibial Ligaments (Deltoid Ligaments) Anterior Tibiotalar Ligament (ATTL) Anterior Distal Tibia Anterior Talar Posterior Tibiotalar Ligament (PTTL) Posterior Distal Tibia Posterior Talar Tibiocalcaneal (& Tibiospring) Excessive Inversion Medial Distal Tibia Medial Calcaneal Ligament Tibionavicular Ligament Distal Tibia Dorsal Navicular 10

11 Ankle Osteology Subtalar joint is formed by posterior, lateral & anterior talar articular surfaces between the calcaneus & talus Sustentaculum Tali is a shelf between the lateral & posterior articular surfaces Tarsi Sinus is the cavity created between the calcaneus & talus 11