First-ever ankle arthrodesis with the Capanna technique in an infected open fracture

Although bone transport by means of distraction osteogenesis has become the standard of care for massive segmental bone defects, the technique faces limitations such as the lengthy period of time during which patients must wear an external fixator. Thus, other techniques may be more appropriate in certain circumstances. Capanna developed a combination of vascularized fibular grafts and strut allografts in a way that the strut allograft provides with significant initial mechanical stability, which facilitates incorporation of a vascularized fibular graft and promotes long-term survival of the reconstruction. The case presented in this report is the first in the medical literature where a circular external fixator is used as a stabilization method in a patient with a structural bone deficiency treated by means of the Capanna technique. It is also one of the few reported cases where the underlying condition does not originate in a tumor and where the joint is involved.

Differential diagnosis between Parkinson's disease and essential tremor using the smartphone's accelerometer

Background

The differential diagnosis between patients with essential tremor (ET) and those with Parkinson’s disease (PD) whose main manifestation is tremor may be difficult unless using complex neuroimaging techniques such as ¹²³I-FP-CIT SPECT. We considered that using smartphone’s accelerometer to stablish a diagnostic test based on time-frequency differences between PD an ET could support the clinical diagnosis.

Methods

The study was carried out in 17 patients with PD, 16 patients with ET, 12 healthy volunteers and 7 patients with tremor of undecided diagnosis (TUD), who were re-evaluated one year after the first visit to reach the definite diagnosis. The smartphone was placed over the hand dorsum to record epochs of 30 s at rest and 30 s during arm stretching. We generated frequency power spectra and calculated receiver operating characteristics curves (ROC) curves of total spectral power, to establish a threshold to separate subjects with and without tremor. In patients with PD and ET, we found that the ROC curve of relative energy was the feature discriminating better between the two groups. This threshold was then used to classify the TUD patients.

Results

We could correctly classify 49 out of 52 subjects in the category with/without tremor (97.96% sensitivity and 83.3% specificity) and 27 out of 32 patients in the category PD/ET (84.38% discrimination accuracy). Among TUD patients, 2 of 2 PD and 2 of 4 ET were correctly classified, and one patient having PD plus ET was classified as PD.

Conclusions

Based on the analysis of smartphone accelerometer recordings, we found several kinematic features in the analysis of tremor that distinguished first between healthy subjects and patients and, ultimately, between PD and ET patients. The proposed method can give immediate results for the clinician to gain valuable information for the diagnosis of tremor. This can be useful in environments where more sophisticated diagnostic techniques are unavailable.