Is the fracture pattern in periprosthetic fractures around the knee related with the anterior femoral notch?

INTRODUCTION: Periprosthetic fractures around the knee (PPF) are a devastating complication of total knee arthroplasty (TKA). Anterior femoral notching during TKA is considered a risk factor for PPF. The aim of this paper is to determine if an anterior femoral notch after total knee arthroplasty may affect the fracture pattern when a PPF appears postoperatively. MATERIAL AND METHODS: 50 patients diagnosed in our centre of a PPF from January 2010 to December 2013 were retrospectively enrolled. 100 patients who underwent a total knee arthroplasty without fracture were randomly obtained as a control group. Evidence of the notch was searched in both groups in postoperative X-rays. In the PPF group, distance from the shield of the femoral component to the most distal (d) and proximal (D) point of the fracture were measured. RESULTS: Two different groups were obtained: 1) d = 0 (33 out of 50 patients); the fracture is supposed to be related with the notch as it's a theoretically weaker area. 2) d > 0 (17 out of 50 patients); the fracture pattern has no relationship with the notch. Prevalence of patients suffering a fracture in the shield of the prosthesis (d = 0), was similar in both patients with notch (66,7%) and without it (68%). CONCLUSIONS: In conclusion, fracture pattern is not related with the existence of a femoral notch in the clinical setting.

Is obesity related with periprosthetic fractures around the knee?

PURPOSE: Periprosthetic fracture (PPF) is a devastating complication following primary total knee arthroplasty. Obesity is currently considered a risk factor for many complications in orthopaedics, but there is no evidence in literature about the relationship between obesity and PPF around the knee. The objective of this study was to determine whether obesity is associated with a higher incidence of PPF. METHODS: All patients diagnosed of a PPF around the knee from January 2010 to December 2013 were enrolled. Forty-nine PPF (47 women and 2 men) were included, and a total of 97 patients (80 women and 17 men) were randomly obtained as a control group. Body mass index (BMI) was obtained in both groups and classified as <25 (normal), overweight (25-29.9), obese (30-34.9), very obese (35-39.9), or morbid obesity (≥40). Both groups, were also divided into subpopulations depending on the age as follows: <70, 70-75, 75-80 and ≥80. Statistical analysis was performed to determine any difference in BMI ≥30 kg/m² distribution between groups. RESULTS: In the PPF group 61.22 % of the patients had a BMI over 30 kg/m² and likewise 62.88 % of the patients in the control group. No association was found between obesity and a higher risk of PPF (p < 0.05). CONCLUSION: As a conclusion, obesity (BMI ≥30 kg/m²) does not have any clinical relationship with the appearance of a periprosthetic fracture around the knee (p < 0.05).

The comparison of measurement accuracy among three different imaging modalities in evaluating elastofibroma dorsi. An analysis of 52 cases.

PURPOSE: Elastofibroma dorsi (ED) is a rare soft-tissue tumour. Diagnosis is made using imaging, mainly magnetic resonance due to its higher sensitivity and specificity in soft tissues. No agreement exists when deciding which imaging test must be used. Often multiple tests are made in the same patient, increasing time and costs. The aim of this paper is to compare the usual imaging exams and evaluate which one is the most accurate when diagnosing and measuring ED. METHODS: A retrospective review was made of those patients who were diagnosed and operated for ED since January 2006 to December 2013. Fifty-two ED were included (19 men, 25 women), and eight of them were bilaterally affected. They were divided into three different groups according to the imaging test used: ultrasound (US) computed tomography (CT) and magnetic resonance (MR). After surgery the pieces were sized and compared with the measurements made by imaging exams. RESULTS: Two hundred fourteen measures were analysed (40 US, 33 CT and 34 MR with their pathological equivalent). When CT group and its corresponding AP were analysed, no significant differences between them were founded (p > 0.05). Moreover, we analysed absolute differences between measures. In the US group a mean difference of 2.23 ± 1.87 cm was obtained. In the CT group, the mean difference was 1.22 ± 0.97 cm. Likewise, the difference of the MR group was 1.62 ± 1.15 cm. CONCLUSIONS: This study demonstrates that the CT obtains a higher correlation than MR when determining the size of ED.