Tibiotalocalcaneal Arthrodesis: A Biomechanical Analysis of the Rotational Stability of the Biomet Ankle Arthrodesis Nail

Abstract

We hypothesized that the posterior-to-anterior (PA) calcaneal interlocking screw of the Biomet Ankle Arthrodesis Nail would increase rotational stability secondary to increased bone purchase compared with the standard lateral-to-medial (transverse) screw. Each of 10 fresh human cadaver lower limbs (five matched pairs) were stabilized with a nail inserted retrograde through the calcaneus, talus, and tibia according to standard technique. One limb of each pair was fixed with a transverse calcaneal screw; the contralateral limb, with a PA calcaneal screw. Each limb was then subjected to torsional testing on an MTS Mini Bionix load frame. The PA screw construct was significantly stiffer than the transverse screw construct: 1.96 and 1.41 Nm/E, respectively (P < 0.036).

Tibiotalocalcaneal arthrodesis with a triple-bend intramedullary nail (A3)—2-year follow-up in 60 patients

“…Intracalcaneal fixation has been shown to be an important factor affecting stability [18,20,27]. Mann et al concluded that the posterior-to-anterior routing of a calcaneal locking screw significantly enhances stability [18]. Muckley et al demonstrated the superiority of angle-stable over non-anglestable intracalcaneal locking [20].…”

“…Many of the patients considered for TTCA have multiple comorbidities affecting bony stability [6][7][8]27]. Intracalcaneal fixation has been shown to be an important factor affecting stability [18,20,27]. Mann et al concluded that the posterior-to-anterior routing of a calcaneal locking screw significantly enhances stability [18].…”

“…The first biomechanical studies in the literature investigated first-generation retrograde (femoral) nails without foot and ankle specific locking options [14][15][16][17]. Secondgeneration nails with foot and ankle specific locking options such as anteroposterior locking within the calcaneus and/or optional compression were designed to increase stability [18][19][20]. In 2010, another system with a triple-bend retrograde intramedullary nail (A3, Stryker, Airview Boulevard, MN, USA) was introduced [1].…”

Tibiotalocalcaneal Arthrodesis with lateral compression Plate

“…In addition to biomechanical stability, factors that may contribute to successful outcomes after TTC arthrodesis include maintenance of anatomic alignment, techniques that are easily reproducible, and preservation of surrounding soft tissues and blood supply (2,7) . Unfortunately, nonunion rates of 15% and higher have been reported in the literature following TTC arthrodesis (2,8) .…”

“…A critical factor when performing these types of salvage procedures is achieving stable fixation with compression of the subtalar and ankle joint (8) . There are many described fixation methods for performing the TTC arthrodesis, including crossed compression screws, intramedullary (IM) fixation, blade plate and locking plates (1,(7)(8)(9)(10) . However, the use of lateral locking plate for TTC fusion has not been described with a specific plate design that conforms to the lateral portion of the tibiotalocalcaneal surface.…”