Step 1: Understanding the Concept:
Postural deformities are abnormal alignments of the skeletal system. Scoliosis and Lordosis are spinal deformities, while Knock-knees and Flat Foot affect the lower limbs.
Step 2: Detailed Differentiation (Scoliosis vs Lordosis):

Step 3: Corrective Measures for Knock-knee and Flat Foot:
Step 4: Final Answer:
Scoliosis is a sideways curve, while Lordosis is a forward lower-back curve. Corrective measures involve specific exercises like Padmasana for Knock-knees and toe-strengthening exercises for Flat Foot.