Independent Risk Factors for Impaired Early Outcome after Isolated Ankle Fracture - A Multivariate Analysis and Prognostic Models. / Unabhängige Risikofaktoren für komplizierte Frühverläufe nach isolierter Sprunggelenksfraktur ­ eine multivariate Analyse und prognostische Modellierung.

BACKGROUND: Ankle fractures are common operative indications in orthopedic surgery. Their incidence is increasing. OBJECTIVES: To identify independent risk factors and to develop prognostic models for the prediction of prolonged length of hospital stay (LOS) and the onset of postoperative complications. MATERIALS AND METHODS: This is a single-center, retrospective, observational study analyzing data of 154 consecutive, isolated, surgically treated ankle fractures. Multivariate binary logistic regression analysis was applied to identify significant independent risk factors. The validity and clinical applicability of the developed prognostic models was assessed with ROC-curve analysis (ROC: Receiver Operating Characteristic). Internal validation of prognostic models was performed with randomized backwards bootstrapping. RESULTS: The median LOS was 7 days. 50 patients (33%) had a longer LOS. 13% of operated patients had a postoperative complication (n = 20). Independent preoperative risk factors for prolonged length of stay were leukocytosis (p = 0.020; OR: 1.211), an increased CRP-level (p = 0.005; OR: 1.901), as well as a bi- (p = 0.002; OR: 15.197) or trimalleolar (p = 0.001; OR: 10.678) fracture type. Immediate operative therapy was an independent beneficial factor (p < 0.001; OR: 0.070). The onset of complications was associated significantly with diabetes mellitus (p = 0.004; OR: 9.903) and an elevated ASA score (p = 0,004; OR: 3.574). The developed prognostic models for the prediction of prolonged LOS (AUROC: 0.736) and postoperative complications (AUROC: 0.724) had a good clinical validity and were internally validated. CONCLUSION: The current data pronounce the importance of preoperative laboratory works. Furthermore, co-morbidities play a major role in the prognosis of outcome. The developed prognostic models are able to reliably predict the outcome and enable the preoperative identification of high-risk patients.

Inflammatory low back pain: high negative predictive value of contrast-enhanced color Doppler ultrasound in the detection of inflamed sacroiliac joints.

OBJECTIVE: To determine the value of microbubble contrast agents for color Doppler ultrasound (CDUS) compared with magnetic resonance imaging (MRI) in the detection of active sacroiliitis. METHODS: An observational case-control study of 103 consecutive patients (206 sacroiliac [SI] joints) with inflammatory low back pain according to the Calin criteria and 30 controls (60 SI joints) without low back pain was conducted at the University Hospital of Innsbruck. All patients and controls underwent unenhanced and contrast-enhanced CDUS and MRI of the SI joints. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of unenhanced and contrast-enhanced CDUS were evaluated. RESULTS: Forty-three patients (41%) with 70 of 206 SI joints (34%) and none of the controls nor the 60 control SI joints demonstrated active sacroiliitis on MRI. Unenhanced CDUS showed a sensitivity of 17%, a specificity of 96%, a PPV of 65%, and an NPV of 72%; contrast-enhanced CDUS showed a sensitivity of 94%, a specificity of 86%, a PPV of 78%, and an NPV of 97%. Detection of vascularity in the SI joint was increased by contrast administration (P < 0.0001). Clustered receiver operating curve analysis demonstrated that enhanced CDUS (A(z) = 0.89) was significantly better than unenhanced CDUS (A(z) = 0.61) for the diagnosis of active sacroiliitis verified by MRI (P < 0.0001; 2-sided test). CONCLUSION: Microbubble contrast-enhanced CDUS is a sensitive technique with a high NPV for detection of active sacroiliitis compared with MRI.

Remitting seronegative symmetrical synovitis with pitting edema of the hands: ultrasound, color doppler ultrasound, and magnetic resonance imaging findings.

OBJECTIVE: To assess the value of gray-scale ultrasound (US), color Doppler ultrasound (CDUS), contrast-enhanced CDUS, and magnetic resonance imaging (MRI) in the diagnostic evaluation of the hands in patients with remitting seronegative symmetrical synovitis with pitting edema (RS3PE). METHODS: Eight patients (5 men, 3 women; mean +/- SD age 69.3 +/- 7.2 years) with clinical diagnosis of RS3PE syndrome underwent US, CDUS, contrast-enhanced CDUS, and MRI. US was performed with a linear array transducer operating at 12 MHz. The US contrast agent (SHU 508; Levovist, Schering, Germany) was intravenously infused in a concentration of 300 mg/ml at a rate of 1 ml/minute. RESULTS: All patients showed symmetric subcutaneous edema and synovitis of tendons and finger joints on both US and MRI. Vascularity was detected subcutaneously in tendon sheaths and in the joint synovia on CDUS and MRI. Detection of increased vascularity was improved after contrast administration compared with unenhanced CDUS (P < 0.01). CONCLUSION: Ultrasound, CDUS, contrast-enhanced CDUS, and MRI are valuable tools in the diagnostic evaluation of involved anatomic structures in patients with RS3PE. Contrast-enhanced CDUS is superior to CDUS in assessment of inflammatory edema, effusion, and synovitis.

Schwannoma of the brachial plexus: cross-sectional imaging diagnosis using CT, sonography, and MR imaging.

Primary brachial plexus tumors are rare, usually benign, and in general have a good prognosis after surgical excision. We present a case of a schwannoma in which sonography enabled the correct diagnosis of a probably benign brachial plexus tumor. Key to the diagnosis was the demonstration of a smooth-bordered, longish, and well-defined nodule along a brachial plexus nerve root. Cross-sectional imaging modalities that provide a high degree of soft tissue contrast and spatial resolution, such as sonography and MR imaging, were suitable methods to establish the correct preoperative diagnosis. Findings at CT, sonography, MR imaging, and surgery are discussed.

Finger pulley injuries in extreme rock climbers: depiction with dynamic US.

PURPOSE: To determine the ability of dynamic ultrasonography (US) to depict finger pulley injuries in extreme rock climbers. MATERIALS AND METHODS: Sixty-four extreme rock climbers (climbing levels 8-11 on a scale ranging from 1 to 11; Union Internationale des Associations d'Alpinisme) with finger injuries (75 symptomatic and 181 asymptomatic fingers) were examined by using US, with the transducer operating at 12 MHz. The distance between the flexor tendon and phalanx was evaluated in extension and forced flexion at the level of the A2 and A4 annular pulleys as an indicator of tendon bowstringing. A distance between the flexor tendon and phalanx greater than 1.0 mm was interpreted as positive for a pulley injury. US findings were compared with those of magnetic resonance imaging. Surgical correlation was available in seven cases. Statistical analysis was performed by using analysis of variance, the Student t test, and the Bonferroni method. RESULTS: US depicted 16 (100%) of 16 complete A2 pulley ruptures, nine (100%) of nine complete A4 pulley ruptures, six (86%) of seven surgically proved complete combined A2 and A3 pulley ruptures, and 15 (100%) of 15 incomplete A2 pulley ruptures. Measurement of distance between the flexor tendon and phalanx was significantly different among patient subsets without pulley ruptures and those with incomplete, complete, or complete combined pulley ruptures (P <.001). The sensitivity of US for depiction of finger pulley injuries was 98%, and specificity was 100%. CONCLUSION: Dynamic US allows excellent depiction of finger pulley injuries in extreme rock climbers.