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Surface landmarks around the hip and gluteal region
length.
• The anterior superior iliac spine is a prominent landmark at the
• The fibular head is palpable laterally (Fig. 52.4). The shaft of the
anterior end of the iliac crest.
fibula is mostly covered but is subcutaneous for the terminal 10 cm.
• The greater trochanter of the femur lies approximately a hands- • The subcutaneous border of the tibia is palpable throughout its
breadth below the iliac crest. It is made more prominent by adducting • The popliteal pulse is difficult to feel as it lies deep to the tibial nerve
the hip. and popliteal vein. It is best felt by palpating in the popliteal fossa with
• The ischial tuberosity is covered by gluteus maximus when the hip the patient prone and the knee flexed.
is extended. It can be palpated in the lower part of the buttock with the
hip flexed. Surface landmarks around the ankle
• The femoral pulse (Fig. 52.1) is most easily felt halfway between • The medial and lateral malleoli are prominent at the ankle. The lat-
the anterior superior iliac spine and the symphysis pubis (mid-inguinal eral is more elongated and descends a little further than the medial.
point). The femoral head lies deep to the femoral artery at the mid- • When the foot is dorsiflexed the tendons of tibialis anterior, extensor
inguinal point. The femoral vein lies medial, and the femoral nerve lat- hallucis longus and extensor digitorum are visible on the anterior
eral, to the artery at this point. aspect of the ankle and the dorsum of the foot.
• The femoral canal (Fig. 52.1) lies medial to the femoral vein within • The tendons of peroneus longus and brevis pass behind the lateral
the femoral sheath. The sac of a femoral hernia passes through the canal malleolus.
to expand below the deep fascia. The hernial sac always lies below and • Passing behind the medial malleolus lie: the tendons of tibialis pos-
lateral to the pubic tubercle (cf. the neck of an inguinal hernia which is terior and flexor digitorum longus, the posterior tibial artery and its
always situated above and medial to the tubercle). The risk of strangula- venae comitantes, the tibial nerve and flexor hallucis longus (Fig.
tion is high in femoral herniae as the femoral canal is narrow and blood 52.3).
flow to viscera within the hernial sac can easily be impaired.
• The great saphenous vein pierces the cribriform fascia in the saph- Surface landmarks around the foot (Fig. 52.5)
enous opening of the deep fascia to drain into the femoral vein 4 cm • The head of the talus is palpable immediately anterior to the distal
below and lateral to the pubic tubercle (Fig. 43.2). tibia.
• In thin subjects the horizontal chain of superficial inguinal lymph • The base of the 5th metatarsal is palpable on the lateral border of
nodes is palpable. It lies below and parallel to the inguinal ligament. the foot. The tendon of peroneus brevis inserts onto the tuberosity on
• The sciatic nerve has a curved course throughout the gluteal region. the base.
Consider two linesaone connects the posterior superior iliac spine and • The heel is formed by the calcaneus. The tendocalcaneus (Achilles)
the ischial tuberosity and the other connects the greater trochanter and is palpable above the heel. Sudden stretch of this can lead to rupture.
the ischial tuberosity (Fig. 52.2). The nerve descends the thigh in the When this occurs a gap in the tendon is often palpable.
midline posteriorly. The division of the sciatic nerve into tibial and • The tuberosity of the navicular can be palpated 2.5 cm anterior to
common peroneal components occurs usually at a point a handsbreadth the medial malleolus. It receives most of the tendon of tibialis posterior.
above the popliteal crease but is highly variable. Sciatic nerve damage • The peroneal tubercle of the calcaneum can be felt 2.5 cm below
is occasionally caused by badly placed intramuscular injections. The the tip of the lateral malleolus.
safest site for intramuscular injection is consequently the upper outer • The sustentaculum tali can be felt 2.5 cm below the medial malleo-
quadrant of the buttock. lus. The tendon of tibialis posterior lies above the sustentaculum tali
• The common peroneal nerve winds superficially around the neck of and the tendon of flexor hallucis longus winds beneath it.
the fibula. In thin subjects it can be palpated at this point. Footdrop can • The dorsalis pedis pulse is located on the dorsum of the foot be-
result from fibular neck fractures where damage to this nerve has tween the tendons of extensor hallucis longus and extensor digitorum.
occurred. • The posterior tibial pulse is best felt halfway between the medial
malleolus and the heel.
Surface landmarks around the knee • The dorsal venous arch is visible on the dorsum of the foot. The
• The patella and ligamentum patellae are easily palpable with the small saphenous vein drains the lateral end of the arch and passes pos-
limb extended and relaxed. The ligamentum patellae can be traced to its terior to the lateral malleolus to ascend the calf and drain into the
attachment at the tibial tuberosity. popliteal vein. The great saphenous vein passes anterior to the medial
• The adductor tubercle can be felt on the medial aspect of the femur malleolus to ascend the length of the lower limb and drain into the
above the medial condyle. femoral vein. This vein can be accessed consistently by ‘cutting down’
• The femoral and tibial condyles are prominent landmarks. With the anterior to, and above, the medial malleolus following local anaesthe-
knee in flexion the joint line, and outer edges of the menisci within, are sia. This is used in emergency situations when intravenous access is
palpable. The medial and lateral collateral ligaments are palpable on difficult but required urgently.
either side of the knee and can be followed to their bony attachments.

Surface anatomy of the lower limb 119