SEM401: Lower Extremity 2

• 2 BONES IN THE LEG
• Tibia


  90% weight bearing
• Tibia


  • Medial
  • UE counterpart: ulna
• Fibula


  10% weight bearing
• Fibula


  • Lateral
  • UE counterpart: radius
• Tibia


  • Most common site of stress fractures in runners secondary to microtrauma
  • Most common site of nonunion fracture in the body, specifically at the distal ⅓ of the tibia due to lack of blood supply
  • 5 Parts: Tibial plateau (condyles), Tibial tuberosity, Tibial crest, Tibial plafond, Medial malleolus
• Fibula


  • 4 parts: Head, Neck, Shaft, Lateral malleolus
• Tibial plateau (condyles)


  Corresponds to the medial femoral condyle, looks like a plate with slight convexity, knee joint is incongruent so the purpose of menisci is to make it deeper
• Tibial tuberosity (TT)


  Clinically significant, Osgood-Schlatter Disease: inflammation, aka "Jumper's Knee", MOI: Repetitive jumping, M > F, boys 10-14 years old, self-limiting condition which is osGOOD because it heals on its own with rest and no WB, bilateral affectation because we jump with both limbs, contraindicated: ultrasound, as deep heating modalities can stunt growth
• Tibial crest


  Sharp (matalim siya) which is why there are no muscular compartments at the medial tibia
• Tibial plafond


  90% WB from above, "Tibial plafond fractures"
• Medial malleolus


  Cannot receive weight bearing
• Fibula head


  • Clinically significant
  • Most common LE PNI entrapment is the Common Peroneal Nerve (CPN), which can result from crossed leg palsy, fracture head of fibula, bedridden patient leg ER,
  • perform trochanter rolls to prevent ER of patient,
  • Patellar Tendon Bearing Cast (PTB) - pressure tolerant areas can WB, pressure sensitive areas can't WB (head of fibula), prolonged icing in the LE: icing of the lateral knee is contraindicated as it can cause neuropraxia = foot drop deformity
• Foot drop deformity


  DF weakness, AKA foot slap, steppage gait pattern, gait compensation: increased hip and knee flexion during swing phase
• Medial malleolus


  • Shorter, anterior
• Lateral malleolus


  • Longer because INV > EV, posterior, inversion 0-35°, eversion 0-15°, INV EV ROM 2:1 = INV sprain is more common, normal out toeing angle of the foot AKA "fick angle" 10-15 degrees
• Superior tibiofibular joint


  UE CP PRU joint, AKA "forgotten joint" because it can cause knee pain, but is often not assessed, type: plane / gliding joint, important to complete ankle DF: during DF, the Sup. T-F joint glides up
• Inferior tibiofibular joint


  UE CP DRU joint, type: syndesmosis / fibrous tissue, ligament here can tear in severe ankle sprains
• Leg muscle compartments


  • Anterior compartment
  • Lateral compartment
  • Posterior compartment
• Anterior compartment muscles


  • "Tom Dick Harry Potter" - Tibialis anterior m., ext. Digitorum longus m., ext. Halucis longus m., Peroneus tertius m., innervation: Deep Peroneal Nerve (DPN) (aka Anterior Tibial N.), action: DF, primary DF = TA m. has very good leverage, if (+) TA m. weakness, all other three can substitute, MC Anterior Compartment Syndrome secondary to trauma or fracture, 5Ps of compartment syndrome: Pain, Paresthesias, Pallor, Pulselessness (in the dorsalis pedis artery, aka dorsal pedal pulse), Paralysis, +1 (6th P) "Polar" Poikilothermia
• Lateral compartment muscles


  • Peroneus longus m., Peroneus brevis m., AKA "fibularis longus/brevis m." since their origin is the fibula, innervation: Superficial Peroneal Nerve (aka Musculocutaneous N.), action: Eversion (Primary Evertors)
• Posterior compartment muscles

  • Superficial: Gastrocnemius, Soleus, Plantaris, innervation: Tibial nerve, action: PF, primary PF - "Triceps Surae" (3 heads configuration of G-S), these muscles form the calf leg (nagpabilog), MMT: isolation technique - to test for the triceps surae: have the px stand, put his hand on the wall, and do 20 tiptoes per L/R leg, to test for only the soleus: have the px bend his knee while tiptoeing (flexing knee during PF → uses the Active Insufficiency principle, wherein the 2-jointed muscle was pre-shortened), Deep: Tibialis posterior, flex. Digitorum longus, flex. Hallucis longus, Popliteus, innervation: Tibial nerve (except popliteus), action: Inversion, all posterior compartment muscles are PF except for popliteus because it only passed through the knee and didn't reach the ankle, (+) Calcaneal gait (Pes Calcaneus) indicates weak PF (heel gait, DF lang yung gumagana), nerve involved in Pes Calcaneus - tibial nerve
• Muscle action in combination

  TA, TP, Pt, Pl/Pb, MMT: direction of resistance is opposite the direction of the muscle, if you want to strengthen your Tibialis Anterior muscles, use the D1 EXTENSION PNF pattern, to strengthen Pt, use the D2 FLEXION PNF pattern
• Ankle region


  Most commonly injured joint in sports because of ankle sprains, AKA "Talocrural joint" (talo = ankle, crural = cross), type: pure hinge joint (ginglymus joint), OPP: 10 PF, CPP: full DF, CP: PF > DF, 3 bones: Medial malleolus (from tibia), Lateral malleolus (from fibula), Talus, ankle mortise - socket formed by the MM and LM intended for the talus, plantarflexion = 0-50 degrees, dorsiflexion = 0-20 degrees, DF has more limited ROM due to the bottom of the talus hitting the ankle mortise, 2 Ligaments: MCL and LCL, MCL: "ANTATI POTATI CATI TINA", anything with "tibia" is MCL, LCL: same as the first 3 but change the "tibia" to "fibula", why is the LCL more famous than the MCL: LCL is weaker since it only has 3 ligaments, the ligaments are separated unlike the deltoid ligament, INV > EV, special tests: Anterior Drawer Test, Talar Tilt Test
• Foot


  • 26 bones in the foot (206 total in the body), Tarsals - 7, Metatarsals - 5, Phalanges - 14, Tarsals: Talus, Calcaneus, Cuboid, Navicular, (3) Cuneiforms, Talus vs. Calcaneus: Talus - aka "Astragalus", MC Tuberculosis of the foot, AVN of talus "Diaz Disease", no muscle attachment, Calcaneus - aka "Os Calcis", largest and first ossify, MC fractured because it's at the heel, Head of talus serve as proximal attachment of the spring ligament, (+) Sustentaculum Tali at the medial calcaneus to support the head of the talus, Metatarsals - forward projection: 2
• LCL


  Lateral Collateral Ligament, weaker than MCL since it only has 3 ligaments and the ligaments are separated unlike the deltoid ligament
• INV > EV


  Inversion is greater than eversion
• Anterior Drawer Test


  To assess the ATFL (Anterior Talofibular Ligament) integrity
• Talar Tilt Test


  To assess the CFL (Calcaneofibular Ligament) integrity
• Bones in the foot

  • 26 bones (206 total in the body)
  • Tarsals - 7
  • Metatarsals - 5
  • Phalanges - 14
• Talus


  Also known as "Astragalus", has no muscle attachment
• Calcaneus


  Also known as "Os Calcis", largest and first to ossify, most commonly fractured because it's at the heel
• Head of talus


  Serves as proximal attachment of the spring ligament
• Sustentaculum Tali


  At the medial calcaneus to support the head of the talus
• Metatarsals


  • Forward projection: 2 > 3 > 1 > 4 > 5
  • 1st MT: Shortest and stoutest
  • 2nd MT: Longest and thinnest, most stable with least mobility, Head - AVN Freiberg's Disease, Shaft - "MARCHSHAFT" March Fracture, stress fracture (MC affected)
  • 5th MT: Base - Jones Fracture, Iselin Disease - apophysitis or inflammation of the epiphysis of the child
• Normal weight bearing ratio of MT head

  • 2:1:1:1:1 (1st MT bears 2x the weight during weight bearing compared to the rest)
• 3 divisions of the foot

  • Hindfoot - talus and calcaneus (aka "real foot", 50% weight bearing)
  • Midfoot - navicular, cuboid, 3 cuneiforms
  • Forefoot - MT, phalanges (50% weight bearing)
• Real Foot Valgus


  Calcaneus moves out, posterior deformity
• Real Foot Varus


  Calcaneus moves in, Club Foot Deformity - MC congenital foot deformity in children; aka "Talipes Equinovarus" (TEV)
• Hallux Valgus


  Normal <15 degrees, MC in arthritis, Big toe