Effects of porous tantalum on periprosthetic bone remodeling around metaphyseal filling femoral stem: a multicenter, prospective, randomized controlled study

Abstract

Periprosthetic bone loss due to adaptive bone remodeling is an important unresolved issue in cementless total hip arthroplasty (THA). The use of porous tantalum on the proximal surface of the femoral stem is expected to decrease postoperative bone loss around the prosthesis through early fixation. We conducted a multicenter randomized controlled study to determine if porous tantalum could reduce periprosthetic bone loss after THA. From October 2012 to September 2014, 118 patients (mean age, 61.5 years; 107 females and 11 males) were prospectively enrolled and were randomly allocated at a ratio of 1:1 to either a metaphyseal filling stem with a proximal porous tantalum coating (Trabecular Metal) or a conventional metaphyseal filling stem with fiber mesh coating (VerSys). Patients underwent dual-energy x-ray absorptiometry scans within 1 week after surgery (baseline) and at 6, 12, and 24 months after surgery to assess periprosthetic bone mineral density (BMD) in the 7 Gruen zones. In addition, the Japanese Orthopaedic Association hip score was assessed before surgery and at 6, 12, and 24 months after surgery. In the proximal periprosthetic region (zones 1 and 7), the Trabecular Metal group had significantly smaller reductions in BMD than the VerSys group throughout the study period. In the VerSys group, significant reductions in BMD compared to baseline were seen at each measurement point in all regions, except in zone 6 at 24 months. In the Trabecular Metal group, no significant reductions in BMD relative to baseline were seen in zones 1, 5, or 6 throughout the study period. Both groups demonstrated similar improvement in Japanese Orthopaedic Association hip scores over the study period. This study demonstrated that a proximally coated stem with porous tantalum has superior results over a conventional stem with titanium fiber mesh in terms of periprosthetic bone remodeling.

Effect of femoral stem surface coating on clinical and radiographic outcomes of cementless primary total hip arthroplasty: a patient-matched retrospective study

“…Level of evidence: level III, retrospective cohort study studies have investigated the effect of other stem coatings on the clinical and radiographic outcomes of THA [11][12][13].…”

Tantalum as Trabecular Metal for Endosseous Implantable Applications

“…The study in [ 95 ] examined the effects of porous Ta on surrounding periprosthetic remodeling around the femoral stem in a group of 118 patients; they randomly received a cementless Ti6Al4V femoral stem for metaphyseal fixation or a conventional titanium stem with fiber mesh coating. Following hip replacement surgery, the periprosthetic bone mineral density (BMD) was monitored by densitometry 1 week after surgery, and 6, 12, and 24 months later.…”

Nanomechanical behavior, adhesion and wear resistance of tin oxide coatings for biomedical applications

“…Indeed, in some cases where wear particles appear as a result of friction, the application of a biomaterial will be limited. In fact, they can lead to periprosthetic bone loss in the tissues surrounding the implant, causing unpleasant tissue reactions such as inflammation [6][7][8]. Biomaterials must, therefore, have a low friction coefficient and high wear resistance.…”