What Is the Long-term Survivorship of Primary and Revision Cemented Distal Femoral Replacements for Limb Salvage of Patients With Sarcoma?

Abstract

Background Cemented endoprosthetic reconstruction after resection of primary bone sarcomas has been in common use for decades. Although multiple studies have reported the survivorship of primary endoprostheses, implant survivorship after revision surgery is less well established. Given that earlier advances in systemic therapy improved survival of patients with sarcoma, the usage of revision endoprostheses can be expected to increase and, as such, understanding revision implant survivorship will help to inform patient and surgeon expectations. Additionally, as new implants are developed that allow alternative reconstruction options, a normative dataset establishing accurate expectations for revision cemented endoprostheses is a critical benchmark by which to measure progress. Questions/purposes (1) What is the implant survivorship free of all-cause revision for primary and revision cemented distal femoral replacements (DFRs) used in the treatment of malignant or benign tumors? (2) What are the most common indications for revision of primary and revision DFRs in an oncology population with mean follow-up of more than 10 years? (3) How does the indication for revision of a primary DFR affect the subsequent risk for and type of revision DFR complication? (4) What patient, tumor, or implant characteristics are associated with improved survivorship free of revision in cemented DFRs used in patients treated initially for primary malignant or benign tumors? Methods This was a retrospective, comparative study using our institution's longitudinally-maintained database of 806 cemented endoprostheses starting in 1980 and assessed through December 31, 2018. In all, 365 DFRs were inserted during this time, but 14% (51 of 365) were placed for nonprimary bone tumors and 1% (5 of 365) were cementless reconstructions, leaving 309 cemented DFRs. Seventyone percent (218 of 309) were primary implants and 29 percent (91 of 309) were revision implants (used to revise a prior DFR in all patients). During this time period, our strong bias was to use cemented stems and, thus, nearly all of our patients had cemented stems. Six percent (13 of 218) of primary DFRs were implanted more than 2 years before the study end; however, they lacked 2 years of follow-up data and, thus, were considered lost to follow-up, leaving Each author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research® editors and board members are on file with the publication and can be viewed on request. Clinical Orthopaedics and Related Research® neither advocates nor endorses the use of any treatment, drug, or device. Readers are encouraged to always seek additional information, including FDA approval status, of any drug or device before clinical use.

CORR Insights®: What Is the Long-term Survivorship of Primary and Revision Cemented Distal Femoral Replacements for Limb Salvage of Patients With Sarcoma?

“…In the current study, Geiger et al [6] reported very long-term results using large-registry data about primary and revision cemented DFRs, which provided valuable information that would not easily be obtained in other ways. The authors found that revision DFR has poorer overall 15-year, 20-year, and 25-year implant survival than primary DFRs do.…”

“…In this study, Geiger et al [6] discovered that stem diameters less than 15 mm in revision cemented DFRs are associated with stem fatigue fractures and aseptic loosening resulting in another revision within 5 years. However, their competing-risk estimator curves showed that even with the use of a stem diameter ≥ 15 mm in revision DFRs, the mean time to implant revision is approximately 10 years, which is still noticeably less than the mean time to implant revision for primary DFRs (18 years).…”

“…However, the high proportion of structural complications in the revision DFR cohort (37%, which was higher than proportions ranging from 11% to 17% in other revision DFR studies [14, 16-18], even though this cohort had a higher proportion of implants with larger-diameter stems than the primary DFR cohort did) makes me wonder what the exact cause was and what we can do to prevent these complications. Unfortunately, most of the causes of structural complications in their revision DFR cohort could not be specified [6]; however, the findings of this study inform us that when performing revision DFRs, surgeons should be concerned about the common potential complications, including structural complications and aseptic loosening, regardless of the type of complication seen in the primary implant.…”

“…The authors found that revision DFR has poorer overall 15-year, 20-year, and 25-year implant survival than primary DFRs do. To my knowledge, Geiger et al [6] are the first to identify a stem diameter less than 15 mm as a factor associated with re-revision surgery for revision cemented DFRs, although the impact of implanting a smaller-diameter stem has been found to be associated with an increased risk of aseptic loosening in primary cemented and cementless DFRs [1, 5]. Geiger et al [6] also found that a porous collar, modularity, and custom cross-pin fixation were not associated with an improved risk of all-cause revision of cemented DFR implants.…”

Editorial Comment: Selected Proceedings From the 2021 Musculoskeletal Tumor Society Meeting

“…Prospective single-institution, longitudinal databases are useful to expand our understanding of factors associated with successful implant outcomes, despite variability among patients treated for bone tumors who underwent reconstruction with cemented distal femoral replacement [3]. The authors of this study showed that increased stem diameter was associated with improved outcomes, and they postulated that decreasing torsional moments around the stem may further improve cemented distal femoral replacement outcomes.…”