Why Does a Wrist Suddenly Drop? Discover the Surprising Cause

Nesredin Hassen Yesuf
21 hours ago
2 min read

By: Nesredin Hassen Yesuf

When the Wrist Won’t Stay Up

Sometimes, a person might notice that the back of their hand hangs loosely, and they can’t lift it no matter how hard they try. This sudden inability to extend the wrist is known as wrist drop. It can be shocking and worrying, especially if there was no clear injury beforehand.

The Pathway of Radial Nerve and its Innervation

The cause of this condition often traces back to a problem with a nerve deep inside the arm. Specifically, it’s the radial nerve — a vital nerve that controls the muscles helping us lift the wrist and fingers. When this nerve gets damaged or compressed, wrist drop can occur [1].

What is Radial Nerve Palsy?

Radial nerve palsy happens when the radial nerve is injured or compressed, disrupting the signals between the brain and the arm muscles. This leads to weakness, numbness, or the classic wrist drop. The radial nerve travels along the back of the upper arm, wrapping around the bone, which makes it vulnerable in certain injuries [2].

Even though it can look alarming, not all cases are permanent. Many people recover completely with time and care depending on the severity and cause of the injury [2].

What Causes It?

Several everyday events can injure the radial nerve. One of the most well-known causes is “Saturday night palsy”, which happens when someone sleeps with their arm draped over a chair or edge, pressing down on the nerve for hours [3].

Another major cause is a fracture of the humeral shaft (the middle part of the upper arm bone), which can directly damage or stretch the radial nerve due to its close contact with the bone [3]. This type of injury is common in falls, road accidents, or trauma.

Other causes include using crutches incorrectly, wearing tight casts, deep cuts to the arm, or even long-term pressure from leaning on hard surfaces. In rare cases, tumors or cysts may press on the nerve, leading to symptoms. Identifying the cause early helps in choosing the best treatment and avoiding long-term problems [3].

Recovery and What to Expect

In mild cases, the nerve heals on its own with rest, splints, and physical therapy. Therapy helps keep the muscles active, prevent stiffness, and speed up recovery. Splints can also support the wrist while the nerve regains function [4].

For more severe cases, doctors might suggest medications, nerve stimulation, or even surgery to repair the nerve or remove any object compressing it. Recovery time can vary. Some people improve in a few weeks, while others may need several months, depending on how early and how well the problem is managed [4].

References

1. Reddy, K. (2021). Understanding wrist drop and nerve injury. Basic NeuroClinics.

2. Sharma, M., & Jain, R. (2022). Radial Nerve Palsy: Anatomy and Causes. Clinical Neuro Review.

3. Al-Tahan, A., et al. (2020). Common upper limb nerve injuries: A simplified review. Journal of Orthopedic Health, 14(3), 212–216.

4. Lin, H. (2023). Recovery from Radial Nerve Palsy: What to Expect. PhysioMed Journal, 18(1), 44–48.

Assessed and Endorsed by the MedReport Medical Review Board