The question of whether pigs have shoulders often arises from the distinction between their anatomy and culinary terms. Pigs do have anatomical structures that serve as shoulders, functionally equivalent to those in humans. This perceived difference often stems from a pig’s quadrupedal stance and how their meat is prepared.
Pig Shoulder Anatomy
A pig’s shoulder is formed by a complex of bones and muscles, primarily involving the scapula (shoulder blade) and the humerus (upper foreleg bone). The scapula is a flat, well-developed bone with a prominent spine that divides its surface. It connects to the humerus at the glenoid cavity, forming a ball-and-socket joint for forelimb movement.
Numerous muscles attach to these bones, creating a robust structure that supports the pig’s body and facilitates movement. Key muscles include the deltoid, supraspinatus, infraspinatus, subscapularis, and various pectoralis muscles, all working together to move the forelimb. Unlike humans, pigs lack a prominent clavicle (collarbone), with their shoulder girdle connected to the body largely by muscle. This muscular arrangement is important for their locomotion and for bearing a significant portion of their body weight.
Pork Shoulder Cuts
In culinary terms, “pork shoulder” refers to a primal cut of meat from the pig’s foreleg and shoulder area. This larger cut is typically divided into two distinct sub-primal cuts: the Boston butt and the picnic shoulder.
The Boston butt, despite its name, comes from the upper part of the shoulder, located above the pig’s foreleg and behind its head. This cut is known for its rich marbling of fat, making it suitable for slow-cooking methods like braising or for making pulled pork.
The picnic shoulder is positioned directly below the Boston butt and extends down to include the foreleg. It is generally leaner than the Boston butt but still contains ample connective tissue, necessitating low and slow cooking to achieve tenderness. The historical term “Boston butt” originated from colonial New England, where butchers would pack less expensive cuts of pork, including shoulder meat, into specialized barrels called “butts.”
Comparing Pig and Human Shoulders
A primary anatomical difference between pig and human shoulders is the clavicle. Humans possess a well-developed clavicle that rigidly connects the shoulder blade to the sternum, enabling a wide range of motion and stability for the arm. Pigs, however, either lack a clavicle entirely or have only a rudimentary, fibrous remnant.
This absence means a pig’s shoulder is primarily connected to its torso by a “muscular sling,” which limits its rotational capabilities compared to human anatomy. Human shoulders are adapted for bipedalism and the intricate manipulation of objects, allowing for extensive arm movements. In contrast, a pig’s quadrupedal stance requires its forelimbs to primarily serve in weight bearing and forward-backward locomotion. Their shoulder structure is specialized for stability and efficient movement along a more restricted plane, rather than broad rotation.