Chapter 8, Problem 1IP

INTRODUCTORY PROBLEMS

1. Construct a chart listing all muscles crossing the hip joint according to whether they are anterior, posterior, medial, or lateral to the joint center. Note that some muscles may fall into more than one category. Identify the action or actions performed by the muscles listed in the four categories.

Summary Introduction

To construct: Chart listing all muscles crossing the hip joint according to whether they are anterior, posterior, medial or lateral to the joint center and identify the actions performed by the muscles listed in the four categories.

Concept introduction: Muscles are soft tissues. Muscles are classified as skeletal muscle, cardiac muscle, and smooth muscle. Skeletal muscles contract and relax with the bones and they help in locomotion, gait and respiration. The articulating connection also known as the joint is the connection between two bones that help both the bones to perform the same function in synchronized fashion.

Explanation of Solution

The muscles of the hip joint help in the movement of the hip. Hip movement is required for locomotion, specialized sports and gait. They are divided into four groups namely: gluteal group, lateral rotator group, adductor group and iliopsoas group.

The following chart shows the muscles of the hip joint, their location and function:

Muscle Group	Hip joint muscles	Location	Function
Gluteal group	Gluteal maximus	Posterior	Involved in hip extension and lateral rotation
	Gluteal medius	Posterior	Involved in abduction and medial rotation of the hip.
	Gluteal minimus	Posterior	Involved in abduction and medial rotation of the hip.
	Tensor fasciae latea	Anterior	Involved in flexion, abduction, and lateral rotation of the hip
Adductor group	Adductor brevis	Anterior Lateral Medial	Involved in adduction and lateral rotation
	Adductor longus	Anterior Lateral Medial	Involved in adduction and flexion of the hip
	Adductor magnus	Anterior Medial	Involved in adduction and lateral rotation
	Pectineus	Anterior Medial	Involved in adduction, medial rotation, and flexion of the hip
	Gracilis	Anterior	Involved in adduction
Iliopsoas group	Iliacus	Anterior	Involved in flexion of hip joint
	Psoas major	Anterior	Involved in flexion of hip joint
Lateral rotator group	Externus obturators	Posterior Medial	Involved in hip outward rotation
	Internus obturators	Posterior	Involved in hip outward rotation
	Piriformis	Anterior Posterior	Involved in hip outward rotation
	Superior gemelli	Posterior	Involved in hip outward rotation
	Inferior gemelli	Posterior	Involved in hip outward rotation
	Quadratus femoris	Posterior	Involved in hip outward rotation
Other muscles Note: They are majorly involved in knee flexion than hip flexion.	Rectus femoris	Anterior	Involved in hip flexion
	Sartorius	Anterior Medial	Involved in hip flexion