If you’ve heard the popular phrase, a “knee-jerk” reaction, then you probably know it’s a descriptive adjective for a predictable, natural, or non-thinking response to a situation. The “knee-jerk” description has deep roots in the medical field, and the reasoning involves the nature of human reflexes.

Long before the days of developed diagnostic imaging, physicians focused on visible cues outside of the body to determine what exactly was occurring on the inside. Ergo, the idea of innate reflexes has been around since the 19th century. Marshall Hall—an English physician—developed the concept of the reflex arc, a neural routeway that facilitates all of the body’s reflexes.

Not long after, other professionals in the field came to realize the diagnostic value of specific deep tendon reflexes. Medical tools came to be—a.k.a. percussion hammers—that evaluated reflexive responses during physical exams. If you’re curious about how these specialty hammers influenced the healthcare industry from invention to modern day, here is everything you should know about medical reflex hammers.

What Are Human Reflexes?

Reflexes are any unconscious, quick, and involuntary responses to stimuli. Every human being performs a number of these reflexes each day, such as sneezing, blinking at bright lights, jumping at loud or unexpected sounds, and vocally reacting in moments of pain. These common types of human reflexes are instinctively fast for one reason: they don’t require thinking or routing through the brain.

Instead, receptor neurons in nerve cells respond to sensed stimuli—such as light, heat, noise, or touch—by sending critical information to sensory neurons. Neurons are key information messengers between the brain and nervous system. These initial receptor neurons further transmit the info to neurons in the spinal cord, which connect to motor neurons and produce a quick movement or response.

Why Reflex Reponses Matter

Various reflexes occur within the human body; some are significant enough to provide critical information on the health and wellness of an individual. Medical professionals use reflex hammers for activating deep reflex tendons. For this reason, understanding the diagnostic nature of these “knee-jerk” responses offers clarity and meaning in the medical community.

During an examination, testing the core reflexes and muscle stretches of the body evaluates the health of the central and peripheral nervous systems. Physicians can keep an eye out for underactive or overactive reflexive responses. An abnormal reflexive response can be a warning sign of an underlying disease or medical problem.

The History of Medical Percussion Hammers

Something significant you should know about medical reflex hammers is the historical timeline of these diagnostic tools. A reflex hammer is one of the most resilient pieces of medical equipment in human history. This invaluable instrument has been around since the 19th century and is still widely used throughout modern medical practice.

Instrument Design: The Initial Originators

After the German physicians Wilhelm Heinrich Erb and Carl Friedrich Otto Westphal uncovered the nature of deep tendon reflexes in the late 1800s, the medical community realized the significant utility of the phenomenon for diagnostic purposes. Erb and Westphal understood that striking a specific tendon with a finger naturally activates the muscle stretch reflex.

Erb suggested a percussion hammer as the preferred instrument for stimulating deep tendon reflexes. At the time, light and small-headed percussion hammers already existed for gentle tapping on chests. Yet, the same is not true for tendon examination.

Experts worked on custom-building reflex hammers to elicit a suitable response. History notes John Madison Taylor as the first inventor of a triangular reflex hammer designed specifically for testing tendon reflexes during medical care.

A Hallmark for Today’s Healthcare Professionals

Numerous variations followed the original design of the instrument, but even advanced technology has not changed the configuration or use of reflex hammers in our modern era. These days, you still see reflex hammers in almost every physical exam or office for diagnosing muscular or nervous system disorders. In the fast-paced world of the 21st century, that’s a remarkable feat for a simple and modest medical device.

How To Use Different Types of Reflex Hammers

The modern medical marketplace is full of percussion hammers used to test a patient’s reflexes, such as the classic triangular Taylor hammer, circular Babinski hammer, and Wartenburg pinwheel neurological hammer.

These products perform similarly to achieve the same results during deep tendon reflex testing. Using a reflex hammer requires few steps: choosing a hammer, holding it firmly, ensuring a relaxed muscle group, and striking the tendon with a single stroke.

You’ll find differences in hammer designs that vary due to location and prevalent practices. Here are the most common models to know more about.

Triangular Reflex Instruments

A Taylor hammer features a pyramidal rubber spearhead attached to a flat metal handle for steady handling. Many professionals like this design for its striking surface that is similar to an extended hand. However, using this American-based hammer requires the right balance and learned skills.

Circular Reflex Instruments

With a rubber ring or Queen’s Square style head attached to a sturdy handle, circular reflex hammers are a solid option for professional use. This familiar design of European hammers is heavier, but proves to be springy, flexible, and painless for testing various tendon reflexes.

Pinwheel Reflex Instruments

As a precision medical device for neurological testing, a traditional Wartenburg pinwheel has a rotating spur with an attached textured handle for secure gripping. Medical professionals use this alternative testing option for evaluating nerve sensitivity, damage, or dysfunction.

Considerations for Purchasing Medical Hammers

No matter the type, investing in a quality reflex hammer is essential for clinical and educational purposes. Consider the best option for your purposes when purchasing a medical hammer.

Remember, a reflex response depends on the velocity, strength, and duration of concentration, alongside the amount of force from the hammer. Examine the mass and length of the hammer to determine the right choice for peak tap force during an examination.

Choose Cascade Health

Are you currently searching for medical-grade healthcare products or specialized supplies? At Cascade Health Care, we understand the significant role of the humble reflex hammer in modern medicine. We carry a selection of reflex hammers for use during a patient’s neurological or diagnostic exams. Browse our high-quality selection to add to your professional diagnostic kit today. Our expert team is here to answer any questions or assist with finding the right medical equipment for your purposes.