Practical assessment of different saw types for field amputation: A cadaver-based study.

Introduction: Field amputation can be life-saving for entrapped patients requiring surgical extrication. Under these austere conditions, the procedure must be performed as rapidly as possible with limited equipment, often in a confined space, while minimizing provider risk. The aim of this study was to determine the ideal saw, and optimal approach, through bone or joint, for a field amputation.

Methods: This was a prospective cadaver-based study. Four saws (Gigli, manual pruning, electric oscillating and electric reciprocating) were tested in human cadavers. Each saw was used to transect four separate long bones (humerus, ulna/radius, femur and tibia/fibula), previously exposed at a standardized location. The time required for each saw to cut through the bone, the number of attempts required to seat the saw when transecting the bone, slippage, quality of proximal bone cut and extent of body fluid splatter as well as the physical space required by each device during the amputation were recorded. Additionally, the most effective saw in the through bone assessment was compared to limb amputation using scalpel and scissors for a through joint amputation at the elbow, wrist, knee and ankle. Univariate analysis was used to compare the outcomes between the different saws.

Results: The fastest saw for the through bone amputation was the reciprocating followed by oscillating (2.1 [1.4-3.7] seconds vs 3.0 [1.6-4.9] seconds). The manual pruning (58.8 [25-121] seconds) was the slowest (p = 0.007). Overall, the oscillating saw was superior or equivalent to the other devices in number of attempts (1), slippage (0), quality of bone cut (100% good) and physical space requirements (4500 cm), and was the second fastest. In comparison, a through joint amputation (125.0 [50-147] seconds for scalpel and scissor; 125.5 [86-217] seconds for the oscillating saw) was significantly slower than through bone with the Gigli (p = 0.029), the oscillating (p = 0.029) and the reciprocal saw (p = 0.029).

Conclusions: The speed, precision, safety, space required, as well as the adjustable blade of the oscillating saw make it ideal for a field amputation. A Gigli saw is an excellent backup for when electrical tools cannot be used. Through bone amputation is faster than a through joint amputation.