The impact of device fixation strategies on 9 cervical disc arthroplasty designs

This study characterizes biomechanical complications reported across 9 Food and Drug Administration (FDA)-approved cervical disc arthroplasty (CDA) devices, stratified by fixation strategy.

Data from the FDA's Manufacturer and User Facility Device Experience (MAUDE) database were reviewed to characterize revision surgical procedures involving 4 primary cervical disc fixation strategies: spike based (PCM, Mobi-C, and Discover), keel based (Prodisc-C, Secure-C, and Prestige-LP), spike-keel combination (M6-C and Simplify), and press-fit (Bryan). Biomechanical complications included migration, heterotopic ossification (HO), subsidence, and osteolysis. Revision surgical procedures were further categorized on the basis of whether cases necessitated repeat arthroplasty or conversion to fusion.

A total of 393 revision cases with biomechanical complications were identified across 4 cervical disc fixation strategies. Migration was the most frequently observed complication (n = 160 [41%]), particularly in spike-based (n = 97 [60.6%]) and keel-based (n = 41 [25.6%]) fixations. Spike-keel hybrids showed 5 cases (3.1%) of migration but displayed the highest rate of osteolysis (n = 35 [77.8%]) and implant breakage over time (n = 17 [47.2%]). HO was particularly observed in spike-based (n = 22 [50%]) and keel-based (n = 15 [34.1%]) devices. Subsidence was also prominent in these groups, affecting 18 cases (41.9%) in spike-based and 20 cases (46.5%) in keel-based devices. Spike based was the only group where revision arthroplasty (n = 203 [76.6%]) exceeded conversion to fusion.

This study characterizes complication patterns across CDA devices with differing fixation strategies, noting variation in the types of biomechanical failures reported in revision cases. Spike- and keel-based devices accounted for the majority of reported cases involving migration, HO, and subsidence, whereas spike-keel hybrid designs may demonstrate improved primary stability and a tendency toward osteolysis. Spike-based fixation was the only method in which revision arthroplasty was more frequent than conversion to fusion, potentially due to reduced bone modification, which may better preserve endplate integrity and enhance the feasibility of arthroplasty reimplantation. These data underscore the importance for further biomechanical and clinical studies to better optimize fixation strategy and complication avoidance in CDA.