Chapter 13 - Section 13.2 - Study Guide - Assess Your Learning Outcomes - Page 504: 11

Here's a breakdown of the nerves that arise from each of the five major spinal nerve plexuses and the body regions or structures to which each nerve provides sensory innervation, motor innervation, or both: **1. Brachial Plexus**: - **Nerves**: - **Axillary Nerve**: Provides motor innervation to the deltoid muscle and sensory innervation to the skin over the deltoid. - **Musculocutaneous Nerve**: Provides motor innervation to the muscles in the anterior arm (e.g., biceps brachii) and sensory innervation to the lateral forearm. - **Radial Nerve**: Supplies motor innervation to the posterior arm and forearm muscles (e.g., triceps brachii) and sensory innervation to the posterior arm, forearm, and dorsal hand. - **Median Nerve**: Provides motor innervation to some forearm and hand muscles and sensory innervation to the palmar aspect of the hand and fingers (except the pinky) and dorsal tips of the first three fingers. - **Ulnar Nerve**: Supplies motor innervation to hand muscles and sensory innervation to the palmar and dorsal aspects of the pinky and part of the ring finger. **2. Lumbosacral Plexus**: - **Nerves**: - **Femoral Nerve**: Provides motor innervation to the quadriceps muscles and sensory innervation to the anterior thigh and medial leg. - **Obturator Nerve**: Innervates the adductor muscles of the thigh and provides sensory innervation to the medial thigh. - **Sciatic Nerve**: The sciatic nerve is a major nerve of the lower limb, composed of the tibial and common fibular (peroneal) nerves. It provides motor innervation to the posterior thigh and leg muscles and sensory innervation to the posterior thigh, leg, and most of the foot. - **Pudendal Nerve**: Innervates the perineal muscles and provides sensory innervation to the perineum, external genitalia, and anal region. **3. Cervical Plexus**: - **Nerves**: - **Phrenic Nerve**: Supplies motor innervation to the diaphragm, which is crucial for breathing, and provides sensory innervation to the central diaphragm and parts of the parietal pleura. **4. Sacral Plexus**: - **Nerves**: - **Tibial Nerve**: Provides motor innervation to most posterior leg muscles and sensory innervation to the posterior leg and sole of the foot. - **Common Fibular (Peroneal) Nerve**: Innervates the muscles of the anterior and lateral leg and provides sensory innervation to the anterior leg and dorsum of the foot. **5. Coccygeal Plexus**: - **Nerves**: - **Coccygeal Nerve**: This plexus is very small and typically contributes to the innervation of a small area around the coccyx, including sensory fibers. Please note that while these are the major nerves originating from each plexus and their primary functions, there are also numerous smaller branches and cutaneous nerves that play additional roles in innervating specific regions within the body. The information provided here highlights the main nerves and their functions associated with each plexus.

Here's a breakdown of the nerves that arise from each of the five major spinal nerve plexuses and the body regions or structures to which each nerve provides sensory innervation, motor innervation, or both: **1. Brachial Plexus**: - **Nerves**: - **Axillary Nerve**: Provides motor innervation to the deltoid muscle and sensory innervation to the skin over the deltoid. - **Musculocutaneous Nerve**: Provides motor innervation to the muscles in the anterior arm (e.g., biceps brachii) and sensory innervation to the lateral forearm. - **Radial Nerve**: Supplies motor innervation to the posterior arm and forearm muscles (e.g., triceps brachii) and sensory innervation to the posterior arm, forearm, and dorsal hand. - **Median Nerve**: Provides motor innervation to some forearm and hand muscles and sensory innervation to the palmar aspect of the hand and fingers (except the pinky) and dorsal tips of the first three fingers. - **Ulnar Nerve**: Supplies motor innervation to hand muscles and sensory innervation to the palmar and dorsal aspects of the pinky and part of the ring finger. **2. Lumbosacral Plexus**: - **Nerves**: - **Femoral Nerve**: Provides motor innervation to the quadriceps muscles and sensory innervation to the anterior thigh and medial leg. - **Obturator Nerve**: Innervates the adductor muscles of the thigh and provides sensory innervation to the medial thigh. - **Sciatic Nerve**: The sciatic nerve is a major nerve of the lower limb, composed of the tibial and common fibular (peroneal) nerves. It provides motor innervation to the posterior thigh and leg muscles and sensory innervation to the posterior thigh, leg, and most of the foot. - **Pudendal Nerve**: Innervates the perineal muscles and provides sensory innervation to the perineum, external genitalia, and anal region. **3. Cervical Plexus**: - **Nerves**: - **Phrenic Nerve**: Supplies motor innervation to the diaphragm, which is crucial for breathing, and provides sensory innervation to the central diaphragm and parts of the parietal pleura. **4. Sacral Plexus**: - **Nerves**: - **Tibial Nerve**: Provides motor innervation to most posterior leg muscles and sensory innervation to the posterior leg and sole of the foot. - **Common Fibular (Peroneal) Nerve**: Innervates the muscles of the anterior and lateral leg and provides sensory innervation to the anterior leg and dorsum of the foot. **5. Coccygeal Plexus**: - **Nerves**: - **Coccygeal Nerve**: This plexus is very small and typically contributes to the innervation of a small area around the coccyx, including sensory fibers. Please note that while these are the major nerves originating from each plexus and their primary functions, there are also numerous smaller branches and cutaneous nerves that play additional roles in innervating specific regions within the body. The information provided here highlights the main nerves and their functions associated with each plexus.