Total knee arthroplasty and periprosthetic distal femoral fracture: looking beyond the osteoporosis to previous osteoporotic fracture.

Osteoporosis increases the risk of periprosthetic distal femoral fractures after TKA, especially in patients with a history of osteoporotic fractures. Therefore, careful assessment and proper treatment of osteoporosis need and the importance of taking osteoporotic medication needs to be recognized by the patients following primary TKA. PURPOSE: Osteoporosis is a risk factor for fractures, including those of the hip, vertebrae, and distal radius; however, the association between osteoporosis and periprosthetic fractures after total knee arthroplasty (TKA) has not been much investigated. Therefore, we aimed to investigate the association of the presence of systemic osteoporosis with periprosthetic fractures after TKA. METHODS: This study included 34 patients with periprosthetic fractures following primary TKA and 106 controls matched for age and sex. Bone mineral density was evaluated at the femoral neck, total hip, and lumbar spine using dual X-ray absorptiometry. Medical records were reviewed for age; sex; body mass index; smoking; rheumatoid arthritis, endocrine diseases, and cardiovascular diseases; history of glucocorticoid use; medication for osteoporosis; and history of previous osteoporotic fracture. In addition, anterior femoral notching after TKA was evaluated. Univariable and multivariable logistic regression analysis were used to determine factors associated with periprosthetic fracture. RESULTS: The prevalence of osteoporosis in the fracture group was higher than that in the control group (61.8% vs. 40.6%, p=0.045). The rate of medication for osteoporosis was significantly low in the fracture group (47.6 % vs 76.7%, p=0.026). History of previous osteoporotic fracture (odds ratio [OR], 9.1; p=0.015) and osteoporosis (OR, 3.6; p=0.013) were significant risk factors for periprosthetic fractures after TKA. Medication for osteoporosis could decrease the risk of periprosthetic fracture (OR 0.3; p=0.020). CONCLUSION: Osteoporosis is a major risk factor for periprosthetic distal femoral fractures after TKA. Therefore, careful assessment and proper treatment of osteoporosis need and the importance of taking osteoporotic medication needs to be recognized to the patients following primary TKA, especially in patients with a history of osteoporotic fracture. LEVEL OF EVIDENCE: Prognostic study, level III.

Osteonecrosis of the hip in Korean patients with systemic lupus erythematosus: risk factors and clinical outcome.

OBJECTIVE: The objective of this paper is to identify the risk factors for development of symptomatic osteonecrosis (ON) and predictors of total hip replacement (THR) among systemic lupus erythematosus (SLE) patients in Korea. METHODS: The medical records of 1051 patients with SLE were reviewed, and 73 patients with symptomatic ON were identified. Among them, 64 patients were eligible for the analysis. Sixty-four age- and sex-matched SLE patients without apparent ON were included as disease controls. The risk factors for development of symptomatic ON were identified by logistic regression analyses. The predictors of THR were determined by Cox proportional hazards regression analyses. RESULTS: Among 64 patients with ON, 59 had ON of the hip and 36 underwent THR. Independent risk factors for development of symptomatic ON included Cushingoid body habitus (OR 21.792 (95% confidence interval (CI) 2.594-183.083)), use of cyclophosphamide (OR 2.779 (95% CI 1.106-6.981)) and azathioprine (OR 2.662 (95% CI 1.143-6.200)). In the Cox proportional hazards model, only advanced radiological stage of ON (Association for Research on Osseous Circulation (ARCO) stage) was a statistically significant predictor of THR. In subgroup analysis with stage I-III ON, multivariate Cox regression analysis showed neuropsychiatric SLE (NPSLE) (HR 6.295 (95% CI 2.178-18.192)) and cumulative prednisolone dose in the first six months after ON diagnosis > 0.9 g (HR 3.238 (95% CI 1.095-9.58)) to be independent predictors. CONCLUSIONS: Advanced ARCO stage at the onset of ON is an independent risk factor for THR in SLE patients with ON. In ARCO stage I-III ON, patients with NPSLE and those receiving > 0.9 g prednisolone during the first six months after the ON diagnosis are likely to require THR.

Fulminant amoebic colitis mimicking intestinal vasculitis in a patient with systemic lupus erythematosus.

Colitis in patients with systemic lupus erythematosus (SLE) is quite rare. It can be caused by intestinal vasculitis, mesenteric vascular thrombosis, concomitant inflammatory bowel disease or infectious colitis. It is important to make an accurate and early diagnosis as the treatments for each condition differ and a delayed diagnosis can result in life-threatening complications. However, non-specific gastrointestinal symptoms make a timely diagnosis challenging. Amoebic colitis is a rare condition in patients with SLE. Here we present a case of fulminant amoebic colitis in a patient with SLE which was initially misdiagnosed as ischemic colitis due to intestinal vasculitis. Her colitis was complicated with multiple intestinal perforations, disseminated intravascular coagulation and acute respiratory distress syndrome; but in the end, the patient was successfully treated with metronidazole and paromomycin.