MOPEC’s Dual Blade SawBones

According to the MOPEC’s booklet, the dual blade SawBones, “is ideal for femoral, humeral or other round bone specimens.” My experience can confirm this statement. The device is safe while processing.

However, bone specimens in a laboratory with an intensive surgical pathology activity, including orthopedic, are not always round. There is a variety of bone configurations. Often, bones are not big enough to be securely placed between the serrated clamps. The space between the clamps is 10 mm. If the specimen is less than 15 mm, it slides down or crashes under the pressure of the saw. The same problem occurs if the specimen is fragile. And last, but not least, the margins of bone resection, sometimes the main goal of the diagnosis, cannot be examined by a cut in the middle of the specimen.

However, if a hard-pressed paking carton is placed above the serrated clamps, many disadventages can be solved. The specimen can placed on the carton mold which could be more or less adjasted to the specimen’s configuration.

Two main areas of improvement of the SawBones use can be suggested: first, the specimen’s immobilization, second, the employment of the saw.

Immobilization

Many of the problems can be solved if the specimen is placed on a cradle like hard-pressed carton mold that rests on the teeth of the base. The upper jaws hold the specimen. In this situation, the size and especially the configuration of the specimen does not matter substantially because the mold can support specimens of different size and shapes. The saw cuts through the specimen along with the carton. Even the margins can be cut if the specimen is placed eccentrically and is held only by one of the upper jaws. If the specimen is bigger than the space between the base and the upper jaw(s), the latter can be taken away and the specimen rests in the carton mold that is pressed into the teeth of the base.

The mold can be easily cut from a hard-pressed packing carton or a disposable carton cafeteria tray. The latter is very convenient because the cup holder can be adjusted to different shapes of the bone specimen.

Saw

The SawBones’s saw has a convenient design. It is easy to change the blade. It is reliable while cutting. The 10 cm space between the blade and the frame is an advantage if the b specimen is thick, especially if soft tissue is attached.

However, the saw is too heavy if the specimen is fragile. For example, even a femoral head with a fracture, especially in a pathological one, crashes under the pressure of the heavy (750 grams) saw. The heavy saw is not appropriate in a case of avascular necrosis of the femoral head due to the fragmentation of the detached cartilage.  Needless to say that such a heavy saw is not suitable for a thin rib.

I placed a MOPEC’s dual blade with 18 or 24 TIN in a standard hack saw frame. Although the SawBones’ saw is STANLEY, the STANLEYhack saw’s frame cannot be used for some technical reasons. A 3-1/8 Great Neck hack saw is appropriate if it is used in the 12 inch blade variant. The Great Neck hack saw with a double blade weighs 395 grams.

In general, the SawBones is a useful instrument. The proposed suggestions can make the device more universal for a pathology laboratory with a high volume of different bone specimens.

Confession

I like my wooden and hard pressed carton devises a little more because I have used them for many years. It seems that they are easier to clean or … discard.

 

 

 

 

 

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