Host response - Orthopaedic Biomaterials in Research and Practice - page 355

Concern was first raised about immune response to metals with
regard to THR arthroplasty when it was proposed that, by producing
local microvascular blockade and bone necrosis, it might play a role in
loosening of high-release-rate MOM prostheses. Several studies have
supported this view, whereas others show either a modest degree or an
absence of association between preoperative sensitization and loosening.
However, of greater interest is the finding that postoperative sensitiza-
tion could occur, owing to the continued release of metal, the formation
of hapten complexes, and the possibility, increasing with postoperative
(implantation) time, of the patient encountering a sensitizing episode
(exposure to various drugs, heat stress, etc.). This has been seen in stud-
ies of sensitivity in patients with metal-on-polymer prostheses, but with
no apparent association to loosening yet demonstrated. Some clinical
series are summarized in Table 14.5. One specific reaction, termed asep-
tic lymphocyte-dominated vascular associated lesion (ALVAL) has seen
continued presentation with, most commonly, MOM THA components,
and is described in more detail below.

Table 14.5 sensitivity to implantation or other exposure
(epicutaneous testing)

% Sensitive to

Subject description Ni Co Cr PMMA

THR patients (metal-on-polymer) (42)
No symptoms (29) 6.9 3.5 nt 21

“Loose” (13) 0 0 nt 100

(Clementi et al. 1980)

THR patients (metal-on-polymer) (64)
No symptoms (28) 3.6 0 0 nt

“Loose” (36) 2.3 5.6 13.9 nt

(Grosshoff et al. 1984)

Schoolgirls (960)
Pierced ears (687) 13 nt nt nt

Unpierced ears (273) 1 nt nt nt

(Larsson-Stymie et al. 1985)

Cobalt-alloy metal workers (853)
Male (485) 0 1.9 0 nt

Female (368) 2.7 8.2 0.8 nt

(Fischer et al. 1983)

Sources: Clementi, D. et al., Ital J Orthop Traumatol 6:97-104, 1980. Fischer,
T., Rystedt, I., Contact Dermatitis 9:115-121, 1983. von Grasshoff, H.
et al., Beitr Orthop Tramatol 31:299-304, 1984. Larsson-Styme, B.,
Widstrom, L., Contact Dermatitis 13:289-293, 1985.
Note: nt, Not tested.