Prelab Images - Anterior Leg & Foot

Prelab Images - Anterior Leg & Foot

Prelab should consist of reading the lab manual and dissector answers and viewing the dissection video. To begin your study, you may find it useful to look over the Netter's or LWW Atlas images listed below.
Step 1. Review the bony landmarks. (Play movie)
The tibia (condyles, tuberosity, soleal line, anterior border, and medial malleolus) and the fibula (head and lateral malleolus) are shown in plate N513 or TG3-08 and TG3-09. The tarsals (calcaneus, talus, navicular, cuboid, and three cuneiform bones), metatarsal, and phalanges are shown in plates N523 or TG3-40 and N524 or TG3-41. Plate N524 or TG3-41 shows that the tarsals are arched both medially and laterally. If you view a foot as it is shown in the bottom picture of plate N523 or TG3-41 you will see that the foot also has a transverse arch (arched in the medial-lateral direction). The tuberosity of the calcaneus and the sustentaculum tali are labeled in plate N525 or TG3-40. The tarsal sinus is shown in plates N523 or TG3-41 and 524. The subtalar joint (joint between the talus and calcaneus) is shown in plates 524 or TG3-60 and N525. The transverse tarsal joint is shown in plates N523 or TG3-41A and 523 or TG3-41B.
Step 2. Remove the remaining subcutaneous tissue from the leg and foot and identify the various specializations of the fascia of the leg and foot. (Play movie)
Remove any remaining skin and subcutaneous tissue from the leg and foot. Be careful while skinning the foot because it is easy to damage the neurovasculature there. Plates N529 or TG3-35 and N530 or TG3-36 show the extensor, flexor, and fibular (peroneal) retinacula. Plate N522 or TG3-32 examines the compartments you will be dissecting.
Step 3. Open the lateral compartment of the leg and identify its muscles. (Play movie)
Plate N521 or TG3-36 shows the fibularis longus and brevis. Plate N535 or TG3-52 shows the tendons of the two muscles in the foot, which you will see later.
Step 4. Open the anterior compartment of the leg and identify the muscles within it; follow their tendons into the foot. (Play movie)
Plate N519 or TG3-37 shows the muscles of the anterior compartment (fibularis tertius is a small muscle that is closely associated with extensor digitorum longus - its tendon is labeled in plate N519 or TG3-37 and N521 or TG3-36 attaching to the fifth metatarsal). Plate N530 or TG3-45 shows the tendons of these muscles in the foot, synovial sheaths, and extensor expansions
Step 5. Trace the vessels and nerves into the lateral and anterior compartments of the leg. (Play movie)
Plate N518 or TG3-35 (and N512 or TG3-38) shows the division of the popliteal artery into anterior and posterior tibial arteries. Plate N518 or TG3-38 also shows the inferior lateral and medial genicular arteries. Plate N518 or TG3-38 shows the anterior tibial artery giving off the posterior tibial recurrent artery and then entering the anterior compartment. Plate N520 or TG3-38 shows the artery in the anterior compartment and giving off the anterior tibial recurrent artery (also see plate N512 or TG3-62). Plate N520 or TG3-62 also shows the anterior medial and lateral malleolar branches of the anterior tibial artery at the ankle (the lateral communicates with the perforating branch of the fibular artery, which will be dissected next). Plate N531 or TG3-47 shows the anterior tibial artery continuing as the dorsalis pedis artery and giving off the arcuate artery (has digital branches) and the deep plantar artery, which dives to the plantar side of the foot to help form the plantar arch (plate N536 or TG3-53). Plate N518 or TG3-38 shows the posterior tibial artery giving off the fibular (peroneal) artery, which has a perforating branch at the ankle that continues into the anterior leg (N520 or TG3-38). Later, you will follow the posterior tibial artery into the foot where it divides into medial and lateral plantar arteries (N534 or TG3-50). The lateral plantar artery and deep plantar artery form the plantar arch that gives off plantar metatarsal branches (N536 or TG3-53). Plate N520 or TG3-39 shows the origin of fibularis longus cut to trace the common fibular (peroneal) nerve. Plate N542 or TG3-65 traces the superficial and deep fibular nerves into the foot and shows their motor and cutaneous distribution (TG3-65C). Plate N518 or TG3-35 shows the tibial nerve in the leg, plate N529 or TG3-39 at the medial malleolus, and plate N535 or TG3-51 shows it dividing into medial and lateral plantar nerves in the foot. Plate N541 or TG3-66AB, TG3-67A, TG3-67B, and TG3-67C shows all the muscle and skin innervated by the tibial nerve in the leg and foot. Once again, plate N522 or TG3-32 shows the leg compartments and plate N512 or TG3-62 shows the collateral blood supply to the knee.
Step 6. Dissect the dorsum of the foot. (Play movie)
Plate N530 or TG3-45 shows the tendons of extensor digitorum and extensor hallucis longus in the foot. Underneath these tendons in the same plate the extensor digitorum brevis and extensor hallucis brevis are labeled. Plates N531 or TG3-46 and N536 or TG3-47 show the anterior tibial artery continuing into the foot as the dorsalis pedis artery and have the deep plantar and arcuate branches labeled. Plate N531 or TG3-47 follows the deep fibular nerve into the foot as it innervates extensor digitorum brevis and extensor hallucis brevis. Plate N542 or TG3-65B and TG3-65C shows the cutaneous distribution of the deep and superficial fibular nerves.
Step 7. Remove the skin and subcutaneous tissue from the plantar foot. (Play movie)
Plate N532 or TG3-48 shows the plantar aspect of the foot after the skin and subcutaneous tissue is removed. Medial and lateral plantar fascia is identified over the medial and lateral compartments. You will also see some branches of the medial and lateral plantar nerves (plate N534 or TG3-50 shows the nerves).
Step 8. Identify and dissect the medial, lateral and central compartments of the foot, identifying fascia, ligaments, muscles, vessels and nerves. (Play movie)
Remove the fascia over abductor hallucis and flexor hallucis brevis (plate N533 or TG3-49). Next, carefully cut through the flexor retinaculum in plate N529or TG3-34. Plates N529 and N534 or TG3-50 and TG3-51 show two different views of the tendons of tibialis posterior, flexor digitorum longus, and flexor hallucis longus passing into the foot with the tibial nerve, posterior tibial artery, and posterior tibial vein. Plates N534 or TG3-50 and N535 or TG3-51 show the division into medial and lateral plantar arteries and nerves and flexor hallucis longus tendon going to the great toe. Plate N532 or TG3-48 shows the calcaneometatarsal ligament and plate N534 or TG3-50 shows the flexor and abductor digiti minimi as well as the lateral plantar artery and nerve. Cut through the middle of the plantar aponeurosis and reflect each half (one half distally toward the toes, the other proximally toward the calcaneus). This should expose a view similar to plate N533 or TG3-49 after all the fascia is cleaned from flexor digitorum brevis.
Step 9. Dissect the adductor-interosseous compartment of the foot, identifying fascia, ligaments, muscles, vessels and nerves. (Play movie)
Next, cut flexor digitorum brevis from its origin on the calcaneus to expose a view like plate N534 or TG3-50. This will allow you to dissect quadratus plantae, the tendons of flexor digitorum longus, the lumbrical muscles, and trace the medial and lateral plantar nerve and artery (plate N534 or TG3-50). Trace the plantar arterial arch underneath quadratus plantae so you do not destroy it when you cut through this muscle. Next, (plate N534 or TG3-50) cut through the middle of quadratus plantae and the flexor digitorum longus tendons and reflect each half (one distally the other proximally). This should allow you to see the two heads of adductor hallucis like in plate N535 or TG3-51. Cutting through the middle of the oblique head of adductor hallucis and reflecting one half medially and the other lateral exposes the interosseous muscles (see plates N535 or TG3-51, N536 or TG3-52, and N537). Plate N536 or TG3-53 shows the plantar arterial arch and the arterial supply to the foot. Plates N534 or TG3-50 and N535 or TG3-51 show the lateral plantar artery dividing into deep and superficial branches. Plates N541 or TG3-53 and N542 or TG3-65 review the motor and cutaneous innervation of the foot. Plate N528 or TG3-61 shows the insertion of tibialis posterior. Once again, plate N515 or TG3-30, TG3-42 or TG3-43 reviews the origins and insertions of all the muscles in this lab.