113.
Metal on metal articulation in total joint arthroplasty of the
trapeziometacarpal joint seems not to represent a major problem
Lene Dremstrup, Maiken Stilling, Torben Bæk Hansen
Department of Orthopaedics, Section of Hand Surgery, and The Orthopaedic
Research Unit Regional Hospital Holstebro, Denmark; Department of
Orthopaedics, Section of Hand Surgery, and The Orthopaedic Research Unit,
Regional Hospital Holstebro, Denmark.; Department of Orthopaedics, Section
of Hand Surgery, and The Orthopaedic Research Unit, Regional Hospital
Holstebro, Denmark.
Background:
Metal on metal articulation in hip resurfacing has lead to
problems with elevated chrome and cobalt blood levels and local reaction to
metal wear particles. Metal on metal articulation is also used in total joint
arthroplasty of the trapeziometacarpal (TMC) joint and in theory this could
also lead to wear problems with elevated serum chrome and cobalt and local
reaction to wear particles.
Purpose / Aim of Study:
We wanted to investigate serum chrome and cobalt
in patients with metal on metal articulation in total joint arthroplasty of the
TMC joint.
Materials and Methods:
Serum chrome and cobalt was measured in 26
patients with total joint arthroplasty of the TMC joint (15 Elektra prosthesis
and 11 Motec prosthesis) at a minimum of two years (mean 44 months (range
25-94))
after the operation and without clinical symptoms of metallosis.
Findings / Results:
In one Elektra patient we found slightly elevated values
(
chrome 10.9 nmol/l and cobalt 25.1 nmol/l). In three Motec patients we also
found slightly elevated values (chrome 25.4 nmol/l and cobalt 25.5 nmol/l;
chrome 13.0 nmol/l and cobalt 27.0 nmol/l; chrome 43.7 nmol/l and 27.0
nmol/l). In three of the four patients with elevated values the value were at a
level previous described in well functioning metal on polyethylene hip
articulation and may be caused by other factors than the implant. The last
patient with the highest values was exposed to metal dust almost daily, which
may be part of the explanation. In the remaining 14 Elektra patients and 7
Motec patients the chrome and cobalt values were normal.
Conclusions:
Metal on metal articulation in total joint arthroplasty of the
TMC joint seems not to represent a major problem. Local reaction to metal
wear particles cannot be excluded based on this study and the patients will be
followed to exclude long-term problems.
