Discrimination between Malignant and Benign Vertebral Fractures Using Magnetic Resonance Imaging

STUDY DESIGN: Retrospective analysis using magnetic resonance imaging (MRI). PURPOSE: To identify MRI features that could discriminate benign from malignant vertebral fractures. OVERVIEW OF LITERATURE: Discrimination between benign and malignant vertebral fractures remains challenging, particularly in patients with osteoporosis and cancer. Presently, the most sensitive means of detecting and assessing fracture etiology is MRI. However, published reports have focused on only one or a few discriminators. METHODS: Totally, 106 patients were assessed by MRI within six weeks of sustaining 114 thoracic and/or lumbar vertebral fractures (benign, n=65; malignant, n=49). The fractures were pathologically confirmed if malignant or clinically diagnosed if benign and were followed up for a minimum of six months. Seventeen features were analyzed in all fractures' magnetic resonance images. Single parameters were analyzed using the chi-square test; a logit model was established using multivariate logistic regression analysis. RESULTS: The chi-square test revealed 11 malignant and 4 benign parameters. Multivariate logistic regression analysis selected (i) posterior wall diffuse protrusion (odds ratio [OR], 48; 95% confidence interval [CI], 4.2–548; p=0.002), (ii) pedicle involvement (OR, 21; 95% CI, 2.0–229; p=0.01), (iii) posterior involvement (OR, 21; 95% CI, 1.5–21; p=0.02), and (iv) band pattern (OR, 0.047; 95% CI, 0.0005–4.7; p=0.19). The logit model was expressed as P=1/[1+exp (x)], x=−3.88×(i)−3.05×(ii)−3.02×(iii)+3.05×(iv)+5.00, where P is the probability of malignancy. The total predictive value was 97.3%. The only exception was multiple myeloma with features of a benign fracture. CONCLUSIONS: Although each MRI feature had a different meaning with a variable differentiation power, combining them led to an accurate diagnosis. This study identified the most relevant MRI features that would be helpful in discriminating benign from malignant vertebral fractures.

Calcar Femorale in Patients with Osteoarthritis of the Hip Secondary to Developmental Dysplasia

BACKGROUND: We investigated whether the calcar femorale, a cortical septum in the region of the lesser trochanter of the femur, correlates with results of femoral stem implantation in patients with osteoarthritis of the hip secondary to developmental dysplasia using computed tomography. METHODS: This retrospective study included 277 hips (41 males and 236 females; age, 37 to 92 years) of patients who had presented to Okayama Medical Center with hip pain. Of these, a total of 219 hips (31 males and 188 females) had previously undergone total hip arthroplasty. According to the Crowe classification, 147 hips were classified as Crowe grade I, 72 hips as Crowe grade II–IV, and 58 hips as normal. RESULTS: The calcar femorale was identified in 267 hips (96.4%). The calcar femorale was significantly shorter and more anteverted in Crowe grade II–IV hips than in Crowe grade I or normal hips. Significant differences in the shape of the calcar femorale were found according to the severity of hip deformity. Three stem designs were analyzed: single-wedge (59 hips), double-wedge metaphyseal filling (147 hips), and modular (13 hips). Single-wedge stems were inserted more parallel to the calcar femorale rather than femoral neck anteversion, while other types of stems scraped the calcar femorale. CONCLUSIONS: The angle of the calcar femorale differs according to the severity of hip deformity, and the calcar femorale might thus serve as a more useful reference for stem insertion than femoral neck anteversion in total hip arthroplasty using a single-wedge stem.

Comparison of Continuous Epidural Analgesia, Patient-Controlled Analgesia with Morphine, and Continuous Three-in-One Femoral Nerve Block on Postoperative Outcomes after Total Hip Arthroplasty

BACKGROUND: Postoperative pain relief can be achieved with various modalities. However, there are only few reports that have analyzed postoperative analgesic techniques in total hip arthroplasty patients. The aim of this retrospective study was to compare the postoperative outcomes of three different analgesic techniques after total hip arthroplasty. METHODS: We retrospectively reviewed the influence of three analgesic techniques on postoperative rehabilitation after total hip arthroplasty in 90 patients divided into three groups (n = 30 patients per group). Postoperative analgesia consisted of continuous epidural analgesia (Epi group), patient-controlled analgesia with morphine (PCA group), or a continuous femoral nerve block (CFNB group). We measured the following parameters relating to postoperative outcome: visual analog scale scores, the use of supplemental analgesia, side effects, length of the hospital stay, plasma D-dimer levels, and the Harris hip score. RESULTS: Each group had low pain scores with no significant differences between the groups. The PCA group had a lower frequency of supplemental analgesia use compared to the Epi and CFNB groups. Side effects (nausea/vomiting, inappetence) and day 7 D-dimer levels were significantly lower in the CFNB group (p < 0.05). There were no significant differences between the groups in terms of the length of the hospital stay or the Harris hip score. CONCLUSIONS: Although there were no clinically significant differences in outcomes between the three groups, the CFNB provided good pain relief which was equal to that of the other analgesics with fewer side effects and lower D-dimer levels in hospitalized patients following total hip arthroplasty.