Search results for "tibia"
showing 10 items of 212 documents
Cerebral potentials elicited by mechanical stimuli to the human leg: influence of artifacts
1992
Mechanical stimulation with a reflex hammer was applied to the quadriceps muscle tendon of healthy volunteers and patients. The time-locked electrical signals were recorded from the scalp. In all cases, reproducible potentials could be recorded, with latencies in a range of 20 ms to 100 ms. The potentials recorded in patients under complete spinal anesthesia were similar to those derived before the anesthesia. In brain dead patients who showed absence of median nerve or posterior tibial nerve SEP, reproducible potentials after mechanical stimuli could be recorded as well. The results suggest that the hammer taps lead to mechanical shock waves which are propagated along the body producing ti…
Analysis of F response in upper motoneurone lesions
2009
The F response can provide a measure of motoneurone excitability (MNE) and so it may be used to investigate upper motoneurone disorders. This report studies the F-wave configuration in patients with stroke to evaluate the changes of the central excitability of the motoneurones at different times after an acute cerebral insult. Various parameters of the F response, including amplitude (absolute and F%/M), duration, and persistence have been determined in 26 patients with unilateral hemiplegia and in 32 healthy subjects of both sexes in the same age range. The investigation was carried out applying a series of 20 supramaximal stimuli at 0.5 Hz on tibial and ulnar nerves bilaterally. In all pa…
Autologous Iliac Bone Graft Compared with Biphasic Hydroxyapatite and Calcium Sulfate Cement for the Treatment of Bone Defects in Tibial Plateau Frac…
2019
Background Bone-graft substitutes are commonly used for the augmentation of traumatic bone defects in tibial plateau fractures. However, their clinical performance compared with that of autologous bone-grafting, the gold standard in bone defect reconstruction, still remains under debate. This study investigates the differences in quality of life, pain, and radiographic outcomes in the treatment of tibial plateau fracture-associated bone defects with either autologous bone grafts or a bioresorbable hydroxyapatite and calcium sulfate cement (CERAMENT BONE VOID FILLER [CBVF]; BONESUPPORT). Methods In this study, 135 patients with acute depression and split-depression fractures of the proximal …
Median and tibial nerve somatosensory evoked potentials: middle-latency components from the vicinity of the secondary somatosensory cortex in humans
1997
The topography of the middle-latency N110 after radial nerve stimulation suggested a generator in SII. To support this hypothesis, we have tried to identify a homologous component in the tibial nerve SEP (somatosensory evoked potential). Evoked potentials following tibial nerve stimulation (motor + sensory threshold) were recorded with 29 electrodes (bandpass 0.5-500 Hz, sampling rate 1000 Hz). For comparison, the median nerve was stimulated at the wrist. Components were identified as peaks in the global field power (GFP). Map series were generated around GFP peaks and amplitudes were measured from electrodes near map maxima. With median nerve stimulation, we recorded a negativity with a ma…
Evidence for early activation of primary motor cortex and SMA after electrical lower limb stimulation using EEG source reconstruction
2006
Compared to median nerve somatosensory evoked potentials (SEP), less is known about activity evoked by nerve stimulation of the lower limb. To understand the mechanisms and the physiology of sensor- and motor control it is useful to investigate the sensorimotor functions as revealed by a standardized functional status. Therefore, we investigated SEPs of the lower limb in 6 healthy male volunteers. For each side, tibial and peroneal nerves were stimulated transcutaneously at the fossa poplitea. The tibial nerves were also stimulated further distally at the ankle joint. Source localization was applied to 64-EEG-channel data of the SEPs. In contrast to somatosensory areas, which are activated …
Sensitivity of laser-evoked potentials versus somatosensory evoked potentials in patients with multiple sclerosis
2003
Somatosensory evoked potentials (SEPs) play a less important role in the diagnosis of multiple sclerosis (MS) than visually evoked potentials. Since standard SEPs only reflect the dorsal column function, we now investigated spinothalamic tract function in patients with MS using laser-evoked potentials (LEPs).LEPs to thulium laser stimuli (3ms, 540 mJ, 5mm diameter) were recorded from 3 midline positions (Fz, Cz, Pz) in 20 patients with MS, and 6 patients with possible but unconfirmed MS. Peak latencies and peak-to-peak amplitude of the vertex potential negativity (N2) and positivity (P2) were evaluated and compared with normative values from 22 healthy control subjects. Median and tibial ne…
Abnormal Somatosensory Evoked Potentials Indicate Compressive Cervical Myelopathy in Mucopolysaccharidoses
2000
Compressive myelopathy at the cranio-cervical junction is a complication of mucopolysaccharidoses (MPS). To detect cervical myelopathy we recorded median and posterior tibial nerve SEPs in 15 patients aged 2.4 - 33.4 years (median 8.8 years) with MPS I-S (n = 3), MPS IVA (n = 8) and MPS VI (n = 4). In addition to the cortical waveforms we recorded the subcortical median nerve SEPs N13b and P13 generated near the cranio-cervical junction and the lemniscal P30 after posterior tibial nerve stimulation. MRI studies in 13 subjects revealed spinal cord compression at the cranio-cervical junction in 10 patients; 5 patients had an increased signal intensity on the T2-weighted initial MRI indicating…
The challenges of monoaxial bone transport in orthopedics and traumatology
2017
Background. Bone defects represent the main challenging problem for the orthopedic surgeon and, consequently, they increase the duration of hospitalization, risk of complications and health expenditures. The aim of our observational, descriptive and retrospective study is to evaluate the outcomes of patients treated with a monolateral external fixator for bone defects greater than 3 cm. Material and methods. Between January 2003 and January 2013, 21 patients were treated at our center by bone transfer with a monolateral external fixator. The main etiologies were trauma in 17 cases (80.9%) and tumors in 4 cases (19.1%). Mean follow-up was 5 years for non-union and 3 years for tumors. Our cl…
Meniscal ramp lesions: diagnostic performance of MRI with arthroscopy as reference standard
2021
Abstract Background The posteromedial meniscal region is gaining interest among orthopedic surgeons, as lesions of this area has been reported to be significantly associated with anterior cruciate ligament tears. The current imaging literature is unclear. Purpose To evaluate the diagnostic performance of MR in the detection of meniscal ramp lesions having arthroscopy as reference standard. Materials and methods We retrospectively included 56 patients (mean age of 25 ± 7 years; 14 females) from January to November 2017 with a arthroscopically proved ACL tear and posterior meniscocapsular separation. On preoperative MRI, two radiologists with 13 and 2 years’ experience in musculoskeletal imag…
High-energy extracorporeal shock wave treatment of nonunions.
2001
Forty-three consecutive patients who did not have healing of tibial or femoral diaphyseal and metaphyseal fractures and osteotomies for at least 9 months after injury or surgery were examined prospectively for use of high-energy extracorporeal shock waves. Former treatment modalities (cast, external fixator, plate osteosynthesis, limitation of weightbearing) remained unchanged. In all cases a 99m Technetium dicarboxyphosphonate regional two-phase bone scintigraphy was performed before one treatment with 3000 impulses of an energy flux density of 0.6 mJ/mm 2 . Radiologic and clinical followups were done at 4-week intervals starting 8 weeks after shock wave treatment. The success criterion wa…