Periprosthetic fractures associated with pin placement in robot- or navigation-assisted total knee arthroplasty: a systematic review and meta-analysis.

The adoption of robotic and computer navigation technologies in total knee arthroplasty (TKA) has expanded rapidly, introducing new device-related complications. Among these, fractures occurring at tracker pin insertion sites have raised increasing clinical concern. This systematic review and meta-analysis evaluated the incidence, observed associations, and clinical outcomes of periprosthetic fractures associated with pin placement in robotic- and navigation-assisted TKA.

Methods

A systematic review and meta-analysis was conducted according to PRISMA 2020 guidelines and prospectively registered in PROSPERO (CRD420261325067). Studies involving adult patients undergoing primary robotic- or navigation-assisted TKA that reported periprosthetic fractures attributable to tracker pin sites were included. Extracted data encompassed study design, navigation or robotic platform, pin configuration, fracture characteristics, and clinical outcomes. A random-effects meta-analysis was performed to estimate the pooled fracture incidence and its 95% confidence interval (CI). Prespecified subgroup analyses examined the influence of pin diameter, cortical engagement, and anatomical pin location.

Results

Seventeen studies encompassing 13,217 robotic- or navigation-assisted TKA procedures met the inclusion criteria. The pooled incidence of pin-related periprosthetic fracture was 0.11% (95% CI, 0.06–0.21%), with moderate heterogeneity (I² = 48%). Increased fracture risk was consistently observed with diaphyseal pin positioning and bicortical fixation compared with metaphyseal or unicortical placement. Additional observed associations included larger pin diameters (≥ 4 mm) and multiple drilling attempts. No evidence of significant publication bias was identified. In reported cases, fracture management led to successful union and satisfactory functional recovery.

Conclusions

Tracker pin–associated periprosthetic fractures are uncommon but clinically meaningful complications of robotic and navigation-assisted TKA. Risk mitigation strategies may include placing metaphyseal unicortical pins, minimizing drilling attempts, and selecting smaller-diameter pins. Heightened caution is warranted in patients with compromised bone quality or elevated body mass index.