Figure 7. Three-dimensional model compares the amount of disruption of the cancellous bone surface between interfragmentary lag screws and memory compression staples in first metatarsophalangeal arthrodesis.

Figure 7A shows a large amount of disruption caused by a lag screw passing directly through the first metatarsophalangeal joint. Figure 7B shows that memory compression staples can provide dynamic compression to the first metatarsophalangeal joint without any contact to the cancellous bone surface of the joint.