Successful bony integration of a porous tantalum implant despite longlasting and ongoing infection: Histologic workup of an explanted shoulder prosthesis

Abstract

Infection associated with an implant is a complication feared in surgery, as it leads to loosening and dysfunction. This report documents an unexpected good bony integration of a porous tantalum shoulder prosthesis despite infection. A shoulder prosthesis with a porous tantalum glenoidal base plate was retrieved after 3 years of ongoing infection with Staphylococcus spp. Methyl-methacrylate embedded sections of the retrieved glenoidal component were analyzed by optical and scanning electron beam microscopy (SEM). Bone ongrowth and ingrowth were quantified. Bone had formed at the implant surface and within the open cell structure of the porous tantalum. The bone implant contact index was 32%. The bone ingrowth or relative bone area within the open structure was 8.2%, respectively 11.9% in the outer 50% of the thickness. Due to the section thickness, bone ongrowth could best be documented in SEM. Despite long-lasting and ongoing infection, the glenoidal base plate of the prosthesis showed good bony integration upon removal. The bone ingrowth into the porous tantalum was comparable to the values previously reported for the undersurface of retrieved proximal humerus resurfacing implants. Good integration of the implant however did not solve the problem of infection, and related morbidity. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2924-2931, 2018.

Porous Tantalum and Titanium in Orthopedics: A Review

“…At least, early to midterm survivorship and clinical outcomes of this TM Glenoid were reported to be reliable. , As for reverse TSA, the TM glenoid base plate was illustrated to be safe and effective in the medium-term . However, different views were presented since no antibacterial property was found in TM glenoid in a revision case with long-lasting infection (Figure e to i) . What’s more, TM glenoid had 25% rate of radiographic metal debris and osteolysis during a minimum 2-year follow-up, to which doctors should pay close attention .…”

“…84 However, different views were presented since no antibacterial property was found in TM glenoid in a revision case with long-lasting infection (Figure 1e to i). 87 What's more, TM glenoid had 25% rate of radiographic metal debris and osteolysis during a minimum 2-year follow-up, to which doctors should pay close attention. 88 TM is not a panacea without a flaw, and complications should be avoided based on these experiences.…”

“…(a, b, c) Section and stereoview of glenoidal component. (d) Overview of the section in low magnification optical microscopy. , High magnification is from e to i. Reproduced with permission from ref . Copyright [2018] [P. Wahl] from John Wiley and Sons.…”

The Clinical Application of Porous Tantalum and Its New Development for Bone Tissue Engineering

“…Nevertheless, it should be noted that the monoblock porous Ta glenoid component may cause trouble when revision TSA is to be performed, for it would be difficult to be removed due to the stable bone–implant interlocking and substantial bone ingrowth even associated with infected host bone [ 128 ], and may subsequently result in central osseous defect or scapular fracture [ 125 ]. Still, accumulated metallic debris deposition derived from the porous Ta component with a time-dependent pattern can still be found after anatomic shoulder arthroplasty, which means that mechanical failure remains a threat in terms of long-term survival rate, and that regular radiographic follow-up should be implemented to verify the stability of the porous Ta glenoid component [ 129 ].…”

The Clinical Application of Porous Tantalum and Its New Development for Bone Tissue Engineering

“…Nevertheless, it should be noted that the monoblock porous Ta glenoid component may cause trouble when revision TSA is to be performed, for it would be difficult to be removed due to stable bone-implant interlocking and substantial bone ingrowth even associated with infected host bone [114] and may subsequently result in central osseous defect or scapular fracture [111]. Still, accumulated metallic debris deposition derived from porous Ta component with a time-depending pattern can still be found after anatomic shoulder arthroplasty, which means mechanical failure remains a threat for long-term survival rate and regular radiographic follow-up should be implemented to verify the stability of the porous Ta glenoid component [115].…”