[Characteristics of 200 patients with suspected implant allergy compared to 100 symptom-free arthroplasty patients]. / Charakteristika von 200 Patienten mit Verdacht auf Implantatallergie im Vergleich zu 100 beschwerdefreien Endoprothesenträgern.

BACKGROUND: Data on implant allergies are incomplete; therefore, we compared the data on allergy history, patch test (PT) and lymphocyte transformation test (LTT) results in a patient series from the Munich implant allergy outpatient department with symptom-free arthroplasty patients. PATIENTS AND METHODS: In this study 200 arthroplasty patients with complaints involving the prosthesis (130 female, 187 knee and 13 hip prostheses) and in parallel 100 symptom-free patients (75 female, 47 knee and 53 hip prostheses) were investigated. A questionnaire-aided history including implant type, cementing, intolerance of dental materials, atopy, cutaneous metal intolerance (CMI) and PT, including a standard series with Ni, Co, Cr, seven bone cement components, including gentamicin and benzoyl peroxide and LTT for Ni, Co and Cr. RESULTS: In the knee arthroplasty patients with complaints 9.1% showed dental material intolerance, 23.5% atopy, 25.7% CMI, 18.2% metal allergies, 7.4% gentamicin allergy and 27.8% positive metal LTT (mostly to Ni). In symptom-free patients 0% showed dental material intolerance, 19.1% atopy, 12.8% CMI, 12.8% metal allergy, 0% gentamicin allergy and 17% positive metal LTT. CONCLUSIONS: Characteristics of the patients with complaints were increased intolerance of dental materials, higher rates of atopy, CMI, metal and gentamicin allergy and LTT reactivity.

[Long-term results of salvage procedures following intrapelvic migration of loosened total hip arthroplasties]. / Langzeitergebnisse nach Rettungsoperationen bei intrapelviner Migration gelockerter Hüftendoprothesen.

INTRODUCTION: Intrapelvic migrations of loosened total hip arthroplasties are rare. Primary objective of revision arthroplasty in these cases is the reconstruction of acetabular defects for example by acetabular reinforcement rings. Presenting 3 cases the possibilities and long-term results of Girdlestone situations or arthrodesis of the hip following intrapelvic migration of a total hip arthroplasty are described. PATIENTS AND METHODS: A Girdlestone procedure was performed in a 62-year-old female patient due to intrapelvic migration of a threaded cup and development of a false aneurysm of the iliac artery. 15 years later the patient was out of any complaints. In another patient an arthrodesis of the hip due to destruction of the acetabulum and central migration of a hemiprosthesis was performed. 15 years later, too, this patient was out of any complaints. In a third patient with a contralateral preexisting Girdlestone hip an arthrodesis of the hip due to excessive loosening and severe acetabular defects of a cemented total hip arthroplasty was performed on the other side. 13 years later both hips were stiff, nevertheless the patient was satisfied. CONCLUSION: Presenting these cases we come to the conclusion that even now a Girdlestone operation or an arthrodesis of the hip should be taken into account if reconstruction of acetabular defects is no more feasible. The long-term results are satisfactory.