Abstracts Posters SICOT-SOF meeting Gothenburg 2010 _2_

Poster
Topic: Arthroplasty - Hip
Abstract number: 25380
HYPERSENSITIVITY AGAINST METAL AFTER TOTAL HIP ARTHROPLASTY
Ryo MIYAGI, Syunji NAKANO, Tateaki SHIMAKAWA
Tokushima City Hospital, Tokushima (JAPAN)
Background: Aseptic lymphocytic vasculitis-associated lesion (ALVAL), a
complication of metal-on-metal arthroplasty, is a late hypersensitivity reaction
mimicking infection. Case: A 71-year-old woman who underwent metal-on-metal total
hip arthroplasty (THA) for hip osteoarthritis (OA) complained of hip pain aggravated
during walking and consequent difficulty in walking at 6 months postoperatively. The
left hip motion was limited to 65° flexion and -40° extension. Radiography revealed a
well-seated metal-on-metal total hip prosthesis without any loosening, osteolysis, or
implant failure. Magnetic resonance imaging showed no abscess formation or liquid
retention. The C-reactive protein level was 23 mg/L; white blood cell count, 5.2 ×
103/mm3 (eosinophil; 4.6%). A skin patch test against cobalt chromium was positive.
A revision surgery performed for severe, 8-month-long pain showed thickened scar
tissue over the implants, suggesting chronic inflammation. Since we suspected metal
hypersensitivity, we replaced the metal liner with a polyethylene liner and inner head.
Pathological examination of the scar revealed lymphocytic infiltration with granuloma,
which is consistent with metal hypersensitivity. Culture examination was negative.
Five months after the second operation, she can walk with a cane without pain.
Discussion: Hypersenstivity reactions are being reported as an important
complication of metal-on-metal arthroplasty in Caucasians but rarely in the Japanese,
probably because this disease entity is not widely acknowledged in the Japanese.
Conclusion: We report a Japanese case of metal hypersensitivity after a metal-onmetal
THA. Metal hypersensitivity should be taken into account when unexplained
pain after metal-on-metal THA is observed.
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