Chapter 4, Problem 3RQ

a.

Summary Introduction

To determine: Whether the humerus moves on the scapula or the scapula moves on the humerus when starting in the anatomical position and moving the shoulder into flexion.

Introduction: Shoulder flexion and extension are the osteokinematic type of motion. This is because the shoulder joint movement is under the voluntary control and osteokinematic motion involves when a bone swings through a range of motion around the axis in a joint such as with extension, abduction, flexion, and rotation.

b.

Summary Introduction

To determine: Whether the proximal end of the humerus is a concave or convex joint surface.

c.

Summary Introduction

To determine: Whether the glenoid fossa of the scapula has a concave or convex joint surface.

d.

Summary Introduction

To determine: Whether the concave surface glides on a fixed convex surface, or a convex surface glides on a fixed concave surface when starting in the anatomical position and moving the shoulder into flexion.

e.

Summary Introduction

To determine: Whether the joint surface glides in the same or in the opposite direction as the distal end of the moving bone.