Long-term results of a soft interface- (Proplast-) coated femoral stem

Abstract

Background Mid-term clinical results of uncemented femoral components with a Proplast coating have been unfavorable and the low modulus system was abandoned in the mid-1990s. There are, however, still substantial numbers of patients with a Proplast-coated prosthesis in situ. We evaluated the clinical and radiographic results in patients with 8-13 year follow-up.Methods We evaluated the survival rate, Harris Hip score and radiographic features of 82 hips in 69 patients. Mean age at operation was 58 (35-72) years.Results With respect to the Harris Hip score (HHS), 21% of the hips were considered to be clinical failures (HHS < 70) at final follow-up, mainly because of excessive thigh pain. Osteolysis was observed in one or more Gruen zones in one-third of the hips. According to the criteria of Engh, 79/82 stems were unstable. 11 hips were eventually revised due to aseptic loosening. Survival of the femoral component of the original cohort at final follow-up was 84% (95% CI: 75-93) in a standard-case scenario.Interpretation Extensive signs of loosening were observed in almost all hips, while not all hips were considered to be clinical failures. Thus, all patients should be thoroughly screened for radiographic progressive osteolysis or the occurrence of thigh pain. Thigh pain or progressive osteolysis warrants revision of the Proplastcoated femoral stem.

PEEK biomaterials in trauma, orthopedic, and spinal implants

“…The low-modulus, porous surface layer was employed in the hopes that it would promote cementless fixation [159]. Unfortunately, the polymer coating led to unacceptably high loosening rates and was ultimately abandoned in the 1990s [160], but unfortunately not before it had been implanted in hundreds of patients.…”

Chronic Infection Leading to Failure of a Composite Femoral Stem: A Report of Two Cases

“…There is a paucity of modern literature regarding composite femoral stem component failure in primary THA. It has been previously demonstrated that the results of the soft interface proplast-coated femoral stem were unfavorable, with reports demonstrating high rates of aseptic loosening and osteolysis [5]. [13].…”

“…There is a paucity of modern literature regarding composite femoral stem component failure in primary THA. It has been previously demonstrated that the results of the soft interface proplast-coated femoral stem were unfavorable, with reports demonstrating high rates of aseptic loosening and osteolysis [5]. Clinical results have been relatively successful to this point for the Epoch composite stem, as with the intermediate-term follow-up of the femoral implant by Akhavan et al, who demonstrated improvement in average Harris hip scores (56 to 97), no instances of component migration, and only one hip with osteolysis [1].…”

“…Human/Animal Rights: All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2008 (5).…”

Fixation and Bone Remodeling Around a Low Stiffness Stem in Revision Surgery

“…Numerous composite stems made of polymer materials reinforced by a central metallic core, carbon fiber, or a flexible metallic construct were tried in a few studies [7,12,17,21,27,29,30,38,41,43,51,52] and also in revisions [25,31]. Even if some of these stems reduced postoperative loss of proximal femoral bone mineral density (BMD), most of them failed clinically as a result of poor fixation.…”