The Mechanics and Biology of Intramedullary Fracture Fixation

Comparison of mechanical rigidity between plate augmentation leaving the nail in situ and interlocking nail using cadaveric fracture model of the femur

“…Tarr and Wiss [14] reported that although plates were strong under torsional force, they were weak under bending forces due to stress concentration through the screw hole. However, intramedullary nails were strong against axial compressive forces and bending forces but were weak against torsional force.…”

“…Fracture healing can be achieved by the formation of peripheral callus since acceptable motion is present at the fracture site. Complications such as shortening, angulation, and rotation, especially in complex fractures, can be minimised with interlocking screws, which may be inserted transversely and/or obliquely through the nail proximal and distal to the fracture site [6,14]. However, as the interlocking intramedullary nails are not canal-filling in the distal shaft or comminuted fractures of the femur, the ability to resist rotational and bending force is limited.…”

Materials in Fracture Fixation

“…This design allowed for elastic compression, strength, stiffness, and the ability of the nail to adapt to the canal. 75,76 Condylocephalic nails enter the bone in the condyles of the metaphysis and usually reach the opposite end of the metaphyseal-epiphyseal area. Examples of condylocephalic nails include Ender and Hackenthall pins.…”

300 Years of Intramedullary Fixation – from Aztec Practice to Standard Treatment Modality

“…Regardless of the implants employed, the universal goal of internal fixation methods has always been to induce bony union after fracture by stabilizing the fracture fragments and maintaining their alignment while permitting the transfer of load across the fracture site during functional activities [54]. The development of aseptic conditions, anesthesia, antibiotics as well as the equipment and implants necessary to employ internal fixation techniques made surgical intervention a viable alternative to conventional fracture treatment methods.…”

“…The development of aseptic conditions, anesthesia, antibiotics as well as the equipment and implants necessary to employ internal fixation techniques made surgical intervention a viable alternative to conventional fracture treatment methods. In fact, internal fixation methods are often regarded as being superior to conventional treatment modalities such as casting, because they allow for a more rapid mobilization of the limb and, thus, an earlier return to physiological activities [41,42,54].…”