Cementing Osseointegration Implants Results in Loosening: Case Report and Review of Literature

Abstract

Skeletal transcutaneous osseointegration was performed on a 54-year-old female transfemoral amputee. None of the available osseointegration implants achieved press-fit stability, so an implant was cemented in position. Although initially stable, by six months the patient reported painful loading and radiographs revealed cement mantle lucency. The osseointegration implant was removed, antibiotics were delivered via implanted spacer and intravenously, and revision osseointegration three months later achieved appropriate immediate press-fit stability. Cemented transcutaneous osseointegration implants loosen within one year. Osseointegration is only successful when bone grows directly onto the implant.

Revision Amputation with Press-Fit Osseointegration for Transfemoral Amputees

“…Template and choose an implant with an optimal diameter that encroaches the inner cortex at the narrowest bone diameter; an implant that is too wide may not fit without causing a large fracture, and an implant that is too narrow may fall out. Do not cement the implant 7 .Ideally, the abutment of the implant should rest against a flat transverse bone end with cortical contact and leave the correct amount of room for the prosthetic knee so that it matches the height of the contralateral knee; avoid inserting an implant too distally or in too wide a metaphyseal flare.Gentle impaction pressure is necessary and small contained distal fractures are acceptable, but avoid causing a propagating fracture. Do not place cerclage cables or loose bone graft at these small fracture sites.Avoid the use of a tourniquet during intramedullary reaming to prevent potential heat-induced osteonecrosis.Nerve surgery such as targeted muscle reinnervation, if indicated, can be performed in the same surgical episode as the osseointegration.The muscles should be closed at the bone-implant interface with use of a tight purse string in order to provide a vascularized tissue barrier against bacterial ingress 8 .The skin surrounding the stoma should have unnecessary fat removed, but not excess removal leading to skin necrosis.…”

“… Template and choose an implant with an optimal diameter that encroaches the inner cortex at the narrowest bone diameter; an implant that is too wide may not fit without causing a large fracture, and an implant that is too narrow may fall out. Do not cement the implant 7 . Ideally, the abutment of the implant should rest against a flat transverse bone end with cortical contact and leave the correct amount of room for the prosthetic knee so that it matches the height of the contralateral knee; avoid inserting an implant too distally or in too wide a metaphyseal flare.…”

“…Template and choose an implant with an optimal diameter that encroaches the inner cortex at the narrowest bone diameter; an implant that is too wide may not fit without causing a large fracture, and an implant that is too narrow may fall out. Do not cement the implant 7 .…”

The Clinical History and Basic Science Origins of Transcutaneous Osseointegration for Amputees

“…Because recent literature recognizes TOFA is safe and effective, and the United States Food and Drug Administration (FDA) has approved one implant design [ 12 ], broader use and innovation is expected. Preventing future problems by considering prior knowledge is essential [ 13 , 14 ]. By providing a consolidated summary of the basic science and early clinical experiments preceding and facilitating modern TOFA, it is hoped that this article can help avoid preventable future problems.…”

Transcutaneous osseointegration for amputees

“…Cementing transcutaneous osseointegration implants is an obvious example: as Mooney et al 9 , 10 reported in the 1970s, this approach fails; when ITAP trials confirmed this, the failure data were withheld, 33 leading to a third generation committing the same error. 40 Awareness of and access to foundational knowledge, along with timely reporting of newly discovered problematic situations, could have prevented this patient’s and potentially future patients’ morbidity, because it is patients — not the surgeons or implant companies — who suffer the consequences of poor clinical outcomes. Recounting lessons is better than recalling implants.…”