You can understand a great deal about the basic structure and function of the lower limb if you learn some basic concepts. Obviously, many of the concepts are the same as those that applied to the upper limb. Some of them might seem painfully obvious, but if you keep them in mind it will save you alot of memorization.
The concept of compartmentalization - The limb is divided into compartments that have common functions on joints and a common innervation - this is the concept of myotomes. This means you don't have to memorize the innervation of each and every muscle. Related to the concept of compartmentalization is the concept of preaxial and postaxial muscles.
Related to the concept of myotomes is the concept of dermatomes. Very important clinically!
Remember, any muscle that crosses a joint, acts on that joint. Refresh your understanding of agonists, antagonists, synergists.
Joints of the lower limb are designed for weight-bearing and locomotion.
A joint receives its innervation from any nerve crossing that joint.
Muscles receive their blood supply from any vessel in the vicinity.
Muscles tend to receive their innervation proximally.