Chronic Systemic Metal Ion Toxicity from Wear on a Revised Cobalt-chromium Trunnion.

INTRODUCTION: Metal toxicity secondary to corrosion and wear has been reviewed in the arthroplasty literature with evidence supporting dermatologic, neurologic, and cardiac involvement. This is the first report of a novel case with the occurrence of systemic pathology with only mildly elevated serum cobalt (Co) and chromium (Cr) levels due to trunnion wear in a metal-on-polyethylene articulation. CASE REPORT: A 45-year-old female who had undergone a revision total hip arthroplasty developed concerning dermatologic, neurologic, and cardiac symptoms. Symptoms were initially attributed to an unknown autoimmune etiology. She had mildly elevated cobalt and chromium levels and subsequently underwent a second revision, this time with complete exchange of the cobalt/chromium components. By her 2-month follow-up, she reported partial resolution of symptoms. She continues to improve more than a year postoperatively. CONCLUSION: Consideration should be given to metal ion toxicity due to trunnion wear in patients with cobalt/chromium femoral components, even with relatively low ion levels.

Obesity Impacts Swelling of Ankle and Foot Joints in Early Rheumatoid Arthritis Patients.

OBJECTIVE: The evaluation of disease activity in obese rheumatoid arthritis (RA) patients presents challenges particularly in the clinical assessment of swollen joints. This study examines the effect of obesity on the American College of Rheumatology (ACR) core set measures used in assessing RA disease activity with specific focus on the swollen joint count (SJC). METHODS: We examined a cross-sectional cohort of 323 early seropositive RA patients (symptom duration ≤15 months). Patients were biologic-naive with equal to or more than 6/44 SJC and equal to or more than 9/44 tender joint count. The ACR core set measures, components of Disease Activity Score (DAS) 44/erythrocyte sedimentation rate (ESR), DAS28/ESR4 item, Clinical Disease Activity Index (CDAI), and body mass index (BMI) were collected. Disease activity measures were compared between BMI categories. Multivariable linear regression models assessed the relationship between high BMI (≥30 kg/m) and lower-extremity (LE) SJC and SJC44 while accounting for other ACR measures. RESULTS: Disease Activity Score 44/ESR4 item, Health Assessment Questionnaire Disability Index, physician global, and SJC44 differed across BMI categories (p < 0.05). Of the SJC44, metacarpophalangeal joints and LE joints (knees, ankles, metatarsophalangeal joints) were associated with increased swelling in all BMI groups (P < 0.05). Obesity was significantly associated with LE SJC after adjusting for ACR core set measures. CONCLUSIONS: There is a direct association between increased BMI and increased swelling of LE joints in RA patients. Increases in DAS44-measured disease activity are higher in obese RA patients because of increased LE swollen joints. Disease Activity Score 28 and Clinical Disease Activity Index, which emphasize upper-extremity joint assessment, are not significantly influenced by obesity.

Contagious weakness in an elderly couple with neurologic emergencies.

We present an unusual neurologic emergency in an elderly male patient. Given his presentation and risk factors, we presumed the initial symptoms to be secondary to a cerebrovascular accident. As the case evolved, however, it became apparent that a more unusual pathology was present. This case report showcases a rare condition masquerading as a common neurologic emergency.