Archive for the ‘Patella or reflex hammer’ Category

There are a number of different designs of these instruments.

They are used to test deep tendon reflexes in the body. You may have seen a doctor ask someone to sit down and cross their legs then with the hammer tap them just below the patella, the knee bone. When all is well the leg will jump. You can do it without crossing the legs. I have seen them used with the pointed end to test reflexes of the bottom of the feet, plantar reflexes, for people who are unconscious.

Below are a number of different designs, in the UK the most common one is the Queen’s square or National hospital pattern. This was designed for the National hospital for nervous diseases in Queen’s square, London. It was modelled on one designed by Henry Vernon of the Great Northern Hospital in the UK in 1858.

It consists of a fairly flexible nylon shaft about a foot long with a pointed end and a head of chromed brass with a rubber ring around it. The pointed end is used for plantar reflexes while the other end is used to test other reflexes. I have seen early versions that had a cane shaft, they also came with a bamboo shaft.

The head is screwed on to the nylon shaft, sometimes this breaks where the shaft joins the head. tease out the nylon remaining in the head, use two small screw drivers, dig them in and twist, then tap a new thread, 1/4 Whitworth or 1/4 UNC (both these are just about the same) and in a soft material like nylon, it won’t make any difference, on to the shaft, re-connect. Over time the rubber ring will perish, you can buy official replacements.

Queens square

Here are some other designs.

This one is a Taylor’s or Tomahawk hammer designed by John Taylor in 1888 in the USA.


This one is called a Buck hammer. There is no point on the end but if you unscrew the end cap it should contain a pin and a brush, they are for doing other tests.


This one is a Babinski’s patella hammer, much the same as the Queen’s square hammer but with a metal shaft, sometimes they are telescopic.


Never seen one of these but it is a Berliner reflex hammer. Not named after the city in Germany but after Herr Bernhard Berliner a German neurologist who designed it around 1910.


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