Muscles of Gluteal Region:

Muscles of the gluteal region are divided into two groups. 

1: Superficial gluteal muscles 

Note: Greater trochanter of femur is site of insertion of gluteus Medius, minimums and piriformis. 

2: Deep gluteal muscles: 

Note: The piriformis muscle is an important landmark in the gluteal region. The superior gluteal nerve and vessels emerge into the gluteal region superiorly to the piriformis. Sciatic nerve enters the gluteal region directly inferior to the piriformis muscle.  

Clinical pearls: 

Trendelenburg Sign: Trendelenburg gait or waddling gait occurs when your hip abductor muscles are weakened. This muscle group includes the gluteus Medius and minimus innervated by superior gluteal nerve. The weakness of these muscles causes drooping of the pelvis to the contralateral side while walking. 

The Trendelenburg sign is produced when the patient is asked to stand without support on each leg. In a positive sign, pelvic drop will occur on the unsupported leg. For example, if the right gluteal muscles are weak, the left side of the pelvis will drop. 

Anterior compartment of thigh muscles:

Note: All the muscles of anterior compartment of thigh are flexors of thigh at hip joint, while quadriceps femoris is extensor of thigh at knee joint and Sartorius also flexes thigh at knee. 

Note:    Sartorius originates from anterior superior iliac spine 

• Rectus femoris originates from anterior inferior iliac spine. 

Medial Compartment of thigh muscles:

Medial compartment consists of five Indvidual muscles. 

All the muscles of medial compartment of thigh causes adduction of thigh at hip joint except obturator externus which causes lateral rotation of thigh at hip joint.  

Gracilis along with adduction at hip joint also assist in flexion at knee joint. 

Posterior thigh muscles:

Also known as hamstrings, consists of three individual muscles. 

Note: All the muscles of posterior compartment of thigh are extensors of thigh at hip and flexors at knee joint. While Biceps femoris is also lateral rotator of thigh at hip joint and Semitendinosus and Semimembranosus also medial rotators of thigh at hip joint 

 Clinical pearls: All the muscles of the posterior thigh originate from the ischial tuberosity of the pelvis. In some cases, mostly in young athletes, sudden and forceful contraction of the hamstring muscles can result in an avulsion fracture of the ischial tuberosity. It can also be associated with sciatic nerve damage. 

Muscles in the anterior compartment of leg:

Anterior leg consists of four muscles. 

Clinical pearls: Foot Drop (Discussed in nerves of the lower limb) 

Muscles in the Posterior compartment of leg:

Consists of seven muscles divided into superficial and deep groups. All are innervated by tibial nerve 

Superficial group: Mnemonic (GPS)

Deep muscles in the posterior leg:

Clinical pearls: 

Ruptured calcaneal tendon: Tear of calcaneal tendon occurs during forceful plantarflexion of the foot. Patients will be unable to plantarflex the foot and affected foot will be permanently dorsiflexed. 

Muscles in the lateral compartment of leg:

Consists of two muscles, fibularis longus and brevis also called peroneus longus and peroneus brevis. 

Muscles of the Sole of foot: 

Muscles of sole of foot. (4 layers) = Must remember highlighted one 

• First layer: Abductor hallucis, flexor digitorum brevis & abductor digitorum minimi 
• Second layer: flexor digitorum accessorius, 4 lumbricals and tendons of flexor hallucis longus and flexor digitorum longus 
• Third layer: flexor hallucis brevis, flexor digitorum minimi brevis & adductor hallucis 
• Fourth layer: Plantar and dorsal interossei muscles, Two long tendons of extrinsic muscles – tibialis posterior and fibularis longus. 

Note: Plantar arteries and nerves lie within the first and second layer of the sole of foot.