A shoulder injury due to an abnormal force may lead to what complication if untreated?

The correct answer highlights the potential for shoulder abduction weakness as a complication following an untreated shoulder injury from an abnormal force. When the shoulder sustains trauma, especially from a high-impact or awkward force, the muscles and tendons that contribute to the shoulder's range of motion can be affected.

In particular, the deltoid muscle, which is essential for shoulder abduction, may experience strain or injury. If an injury is not properly addressed, it can lead to weakness in this muscle over time. This weakness can manifest as difficulty or an inability to raise the arm away from the body, which is a crucial aspect of shoulder function. Understanding the relationship between trauma and muscle function is pivotal, as neglecting to treat shoulder injuries can lead to long-term mobility issues.

Shoulder dislocation, rotator cuff tear, and arthritis are also potential complications of shoulder injuries. However, they focus more on structural damage or degenerative changes rather than directly causing weakness in the specific motion of abduction. Deltoid and other related musculature's integrity is fundamental for this particular motion, making shoulder abduction weakness a pertinent consequence of untreated injury in this context.