What Factors Are Associated With Failure of Compressive Osseointegration Fixation?

Abstract

Background Compressive osseointegration is as an alternative to traditional intramedullary fixation. Two-to 10-year survivorship and modes of failure have been reported; however, as a result of relatively small numbers, these studies are limited in their ability to identify risk factors for failure. Questions/purposes (1) What is survivorship free from aseptic mechanical and survivorship free from overall failure of compressive osseointegration fixation? (2) What patient factors (age, sex, body mass index [BMI], anatomic location of reconstruction, indication for reconstruction, radiation, chemotherapy) are associated with increased risk of failure?Methods Between 2006 and 2014, surgeons at one center treated 116 patients with 137 Compress 1 implants for lower extremity oncologic reconstructions, revision arthroplasty, and fracture nonunion or malunion. One hundred sixteen implants were available for review with a minimum of 2-year followup (mean, 4 years; range, 2-9 years). Kaplan-Meier survival plots were produced to examine survivorship and Cox regression modeling was used to generate hazard ratios (HRs) for potential risk factors for failure. Patient factors (age, sex, BMI, anatomic location of reconstruction, indication for reconstruction, radiation, chemotherapy) were obtained from chart review and an institutional database. Results Survivorship free from aseptic mechanical failure was 95% (95% confidence interval [CI], 91%-99%) at 18 months and 93% (95% CI, 86%-99%) at 4 years. Survivorship free from overall failure was 82% (95% CI, 75%-89%) at 18 months and 75% (95% CI, 66%-84%) at 4 years. Risk of overall failure was increased with reconstruction of the proximal tibia (HR, 4.42;) and distal femur (HR, 1.74; 95% CI, 0.50-6.09) compared to the proximal femur (HR, 1; referent; p = 0.049). Risk of aseptic mechanical failure was increased with reconstruction of the proximal tibia (HR, 1; referent) and distal femur (HR, 0.37; 95% CI, 0.08-1.77) compared with the proximal femur (HR, 0, p = 0.048). Radiation was associated with increased risk of overall failure (HR, 3.85; 95% CI, 1.84-8.02; p \ 0.003), but not aseptic mechanical failure. Age, sex, BMI, chemotherapy, and surgical indication were not associated with increased risk of aseptic or overall failure. Conclusions This study questions the use of age as a contraindication for the use of this technology and suggests this technology may be considered in proximal femoral reconstruction and for patients with indications other than

Is there a time delay to achieve stable compressive osseointegration fixation?

“…Due to the nature of this retrospective review, we were unable to accurately assess or measure patients' adherence to weight-bearing recommendations, or to study differing weight-bearing restrictions in matched cohorts as would be ideal in a randomized controlled trial. Other modes of failure of compressive osseointegration fixation include periprosthetic fracture around a stable implant, infection, or progression of oncologic disease [4,23,27,28,31] , all of which are clinically relevant but outside the scope of this study.…”

“…A previous study found that risk of overall failure of proximal tibia and distal femur reconstructions was increased compared to the proximal femur with the Compress® device [27] .…”

“…This technology uses a spring-loaded device to generate an axially-directed compressive force across the bone-implant interface. This self-adjusting compressive force is continuously applied promoting biologic fixation by inducing bone hypertrophy and osseointegration at the implant interface [4,5,15,21,[24][25][26] which has the potential to decrease the rate of aseptic mechanical failure [19,27] . Other advantages of the Compress® device include the ability to use it for short-segment fixation and it prohibits loss of bone stock [4,19,20,25,28,29] if later revision surgeries are required [4] .…”

“…Other advantages of the Compress® device include the ability to use it for short-segment fixation and it prohibits loss of bone stock [4,19,20,25,28,29] if later revision surgeries are required [4] . Aseptic mechanical failure of compressive osseointegration fixation occurs when stable bony integration at the bone-implant interface fails to develop in the absence of infection, potentially leading to implant loosening at the spindle or fracture around the anchor plug [15,23,24,27,28,30,31] . Current manufacturer recommendations include 6 weeks of restricted weight bearing to allow for osseointegration to occur; however, the time delay to achieve stable fixation has yet to be established.…”

AE-Beitrag: Megaimplantate am proximalen Femur: aktuelle Evidenz, Systemunterschiede und Portfolioempfehlung

“…Zum Impaction Grafting beim proximalen Femurersatz liegen nach aktuellem Kenntnisstand keine wegweisenden Studien vor. [20,21]. Klinisch konnte gezeigt werden, dass durch das Compress-System Überlebensraten der Femurfixation von 88 % nach 5 Jahren erzielt werden können.…”