Athletic injuries of the extensor carpi ulnaris subsheath: MRI findings and utility of gadolinium-enhanced fat-saturated T1-weighted sequences with wrist pronation and supination

Purpose: To report the magnetic resonance imaging (MRI) findings in athletic injuries of the extensor carpi ulnaris (ECU) subsheath, assessing the utility of gadolinium-enhanced (Gd) fat-saturated (FS) T1-weighted sequences with wrist pronation and supination. Methods and Materials: Sixteen patients (13 males, 3 females; mean age 30.3 years) with athletic injuries of the ECU subsheath sustained between January 2003 and June 2009 were included in this retrospective study. Initial and follow‑up 1.5-T wrist MRIs were performed with transverse T1-weighted and STIR sequences in pronation, and Gd FS T1-weighted sequences with wrist pronation and supination. Two radiologists assessed the type of injury (A to C), ECU tendon stability, associated lesions and rated pulse sequences using a three-point scale: 1 = poor, 2 = good and 3 = excellent. Results: Gd-enhanced FS T1-weighted transverse sequences in supination (2.63) and pronation (2.56) were most valuable, compared with STIR (2.19) and T1 weighted (1.94). Nine type A, one type B and six type C injuries were found. There were trends towards diminution in size, signal intensity and enhancement of associated pouches on follow‑up MRI and tendon stabilisation within the ulnar groove. Conclusion: Gd-enhanced FS T1-weighted sequences with wrist pronation and supination are most valuable in assessing and follow‑up athletic injuries of the ECU subsheath on 1.5-T MRI.

Athletic injuries of the extensor carpi ulnaris subsheath: MRI findings and utility of gadolinium-enhanced fat-saturated T1-weighted sequences with wrist pronation and supination.

OBJECTIVE: To report the magnetic resonance imaging (MRI) findings in athletic injuries of the extensor carpi ulnaris (ECU) subsheath, assessing the utility of gadolinium-enhanced (Gd) fat-saturated (FS) T1-weighted sequences with wrist pronation and supination. METHODS: Sixteen patients (13 male, three female; mean age 30.3 years) with athletic injuries of the ECU subsheath sustained between January 2003 and June 2009 were included in this retrospective study. Initial and follow-up 1.5-T wrist MRIs were performed with transverse T1-weighted and STIR sequences in pronation, and Gd FS T1-weighted sequences with wrist pronation and supination. Two radiologists assessed the type of injury (A to C), ECU tendon stability, associated lesions and rated pulse sequences using a three-point scale: 1=poor, 2=good and 3=excellent. RESULTS: Gd-enhanced FS T1-weighted transverse sequences in supination (2.63) and pronation (2.56) were most valuable, compared with STIR (2.19) and T1-weighted (1.94). Nine type A, one type B and six type C injuries were found. There were trends towards diminution in size, signal intensity and enhancement of associated pouches on follow-up MRI and tendon stabilisation within the ulnar groove. CONCLUSION: Gd-enhanced FS T1-weighted sequences with wrist pronation and supination are most valuable in assessing and follow-up athletic injuries of the ECU subsheath on 1.5-T MRI.

The use of weightbearing radiographs to assess the stability of supination-external rotation fractures of the ankle

Isolated lateral malleolar fractures usually result from a supination-external rotation (SER) injury and may include a deltoid ligament rupture. The necessity of operative treatment is based on the recognition of a relevant medial soft-tissue disruption. Currently used tests to assess ankle stability include manual stress radiographs and gravity stress radiographs, but seem to overestimate the need for fracture fixation.

Hindfoot joint pressure in supination sprains

Hindfoot trauma including ankle and subtalar sprains may be followed by osteochondral lesions and persisting pain originating from posttraumatic arthritis.

Fracture Of Distal Humerus: Mipo Technique With Visualization Of The Radial Nerve.

To evaluate the outcomes in patients treated for humerus distal third fractures with MIPO technique and visualization of the radial nerve by an accessory approach, in those without radial palsy before surgery. The patients were treated with MIPO technique. The visualization and isolation of the radial nerve was done by an approach between the brachialis and the brachiorradialis, with an oblique incision, in the lateral side of the arm. MEPS was used to evaluate the elbow function. Seven patients were evaluated with a mean age of 29.8 years old. The average follow up was 29.85 months. The radial neuropraxis after surgery occurred in three patients. The sensorial recovery occurred after 3.16 months on average and also of the motor function, after 5.33 months on average, in all patients. We achieved fracture consolidation in all patients (M=4.22 months). The averages for flexion-extension and prono-supination were 112.85° and 145°, respectively. The MEPS average score was 86.42. There was no case of infection. This approach allowed excluding a radial nerve interposition on site of the fracture and/or under the plate, showing a high level of consolidation of the fracture and a good evolution of the range of movement of the elbow. Level of Evidence IV, Case Series.

Neuromuscular-skeletal constraints upon the dynamics of unimanual and bimanual coordination

In the first of three experiments, 11 participants generated pronation and supination movements of the forearm, in time with an auditory metronome. The metronome frequency was increased in eight steps (0.25 Hz) from a base frequency of 1.75 Hz. On alternating trials, participants were required to coordinate either maximum pronation or maximum supination with each beat of the metronome. In each block of trials, the axis of rotation was either coincident with the long axis of the forearm, above this axis, or below this axis. The stability of the pronate-on-the-beat pattern, as indexed by the number of pattern changes, and the time of onset of pattern change, was greatest when the axis of rotation of the movement was below the long axis of the forearm. In contrast, the stability of the supinate-on-the-beat pattern was greatest when the axis of rotation of the movement was above the long axis of the forearm. In a second experiment, we examined how changes in the position of the axis of rotation alter the activation patterns of muscles that contribute to pronation and supination of the forearm. Variations in the relative dominance of the pronation and supination phases of the movement cycle across conditions were accounted for primarily by changes in the activation profile of flexor carpi radialis (FCR) and extensor carpi radialis longus (ECR). In the Final experiment we examined how these constraints impact upon the stability of bimanual coordination. Thirty-two participants were assigned at random to one of four conditions, each of which combined an axis of rotation configuration (bottom or top) for each limb. The participants generated both inphase (both limbs pronating simultaneously, and supinating simultaneously) and antiphase (left limb pronating and right limb supinating simultaneously, and vice versa) patterns of coordination. When the position of the axis of rotation was equivalent for the left and the right limb, transitions from antiphase to inphase patterns of coordination were Frequently observed. In marked contrast, when the position of the axis of rotation for the left and right limb was contradistinct, transitions From inphase to antiphase patterns of coordination occurred. The results demonstrated that when movements are performed in an appropriate mechanical context, inphase patterns of coordination are less stable than antiphase patterns.

The acquisition of movement skills: Practice enhances the dynamic stability of bimanual coordination

During bimanual movements, two relatively stable inherent patterns of coordination (in-phase and anti-phase) are displayed (e.g., Kelso, Am. J. Physiol. 246 (1984) R1000). Recent research has shown that new patterns of coordination can be learned. For example, following practice a 90 degrees out-of-phase pattern can emerge as an additional, relatively stable, state (e.g., Zanone & Kelso, J. Exp. Psychol.: Human Performance and Perception 18 (1992) 403). On this basis, it has been concluded that practice leads to the evolution and stabilisation of the newly learned pattern and that this process of learning changes the entire attractor layout of the dynamic system. A general feature of such research has been to observe the changes of the targeted pattern's stability characteristics during training at a single movement frequency. The present study was designed to examine how practice affects the maintenance of a coordinated pattern as the movement frequency is scaled. Eleven volunteers were asked to perform a bimanual forearm pronation-supination task. Time to transition onset was used as an index of the subjects' ability to maintain two symmetrically opposite coordinated patterns (target task - 90 degrees out-of-phase - transfer task - 270 degrees out-of-phase). Their ability to maintain the target task and the transfer task were examined again after five practice sessions each consisting of 15 trials of only the 90 degrees out-of-phase pattern. Concurrent performance feedback (a Lissajous figure) was available to the participants during each practice trial. A comparison of the time to transition onset showed that the target task was more stable after practice (p = 0.025). These changes were still observed one week (p = 0.05) and two months (p = 0.075) after the practice period. Changes in the stability of the transfer task were not observed until two months after practice (p = 0.025). Notably, following practice, transitions from the 90 degrees pattern were generally to the anti-phase (180 degrees) pattern, whereas, transitions from the 270 degrees pattern were to the 90 degrees pattern. These results suggest that practice does improve the stability of a 90 degrees pattern, and that such improvements are transferable to the performance of the unpractised 270 degrees pattern. In addition, the anti-phase pattern remained more stable than the practised 90 degrees pattern throughout. (C) 2001 Elsevier Science B.V. All rights reserved.

Extensor carpi ulnaris (ECU) subsheath: Normal MRI appearance and findings in athletic injuries : 40

Purpose: First, to report ECU subsheath's normal MRI appearance and the findings in athletic injuries. Second, to determine the best MRI sequence for diagnosis. Methods and materials: Sixteen patients (13 males, 3 females, mean age 30.3 years) with ECU subsheath's athletic injuries sustained between January 2003 and June 2009 were retrospectively reviewed. Wrist MRI studies were performed on 1.5-T units and consisted of at least transverse T1 and STIR sequences in pronation, and FS Gd T1 in pronation and supination. Two radiologists assessed the following items, in consensus: injury type (A to C according to Inoue), ECU tendon stability, and associated lesions (ulnar head oedema, extensor retinaculum injury, ECU tendinosis and tenosynovitis). Then, each reader independently rated the sequences' diagnostic value: 0 = questionable, 1 = suggestive, 2 = certain. Follow-up studies were present in 8 patients. ECU subsheath's normal visibility (medial, central and lateral parts) was retrospectively evaluated in 30 consecutive control MRI studies. Results: FS Gd T1 sequences in supination (1.63) and pronation (1.59) were the most valuable for diagnosis, compared to STIR (1.22) and T1 (1). The study group included 9 type A, 1 type B and 6 type C injuries. There were trends towards diminution in pouches' size, signal intensity and enhancement in follow-up studies, along with tendon stabilization within the ulnar groove. In control studies, ECU subsheath's visibility in medial, central and lateral parts were noted in 66.7-80%, 63.3-80% and 30-50% respectively. Conclusion: ECU subsheath's athletic injuries are visible on 1.5-T MRI studies. FS Gd T1 sequences in supination and pronation are the most valuable.

Fracturas inestables de radio distal. Nuestra experiencia en osteosíntesis con placa volar de ángulo variable

OBJECTIVE: assess the functional, subjective and radiological results obtained in patients treated with variable-angle locking plate for unstable distal radius fracture and compare these results with current studies. PATIENTS AND METHOD: From October of 2008 to July of 2011, 20 patients were included who had undergone intervention using the volar approach to the Flexor Carpi Radialis. The average follow up was 18 months. Both clinical and radiological results were analyzed. The Mayo Wrist Score and DASH questioner were used. RESULTS: The average age was 50 years; 50% men and 50% women. The consolidation of the fracture was verified in all cases. An average volar angle was obtained of 5º, radial inclination of 19º, radial height of 10.5 mm, and ulnar variance of -1 mm. The clinical assessment revealed an average dorsal flexion of 75º, palm flexion of 70º, supination of 75º and pronation of 73 º. The results for the DASH questionnaire showed an average of 17.8 and 82.7 for the Mayo Wrist Score. CONCLUSIONS: Our experience has provided some good results, both in functional and subjective as well as radio logical terms, similar to those found in studies with implants from the same generation.

Validity of the "Drift without pronation" sign in conversion disorder.

BACKGROUND: Conversion disorder (CD) is a psychiatric disorder, yet the diagnosis cannot be established without the expertise of a neurologist, as distinguishing a functional from an organic symptom relies on careful bedside examination. Joseph Babinski considered the absence of pronator drift as a 'positive sign' for hysterical paresis but the validity of this sign has never been evaluated. The aim of this study was to examine the sensitivity and specificity of the "drift without pronation" sign. METHODS: Twenty-six patients with unilateral functional upper limb paresis diagnosed with CD (DSM-IV) and a control group of 28 patients with an organic neurological condition were consecutively included. The arm stabilisation test was performed with arms stretched out in full supination, fingers adducted, eyes closed for 10 seconds. A positive "drift without pronation" sign was defined by the presence of a downward drift without pronation. RESULTS: All CD subjects (100%) displayed a positive sign when only 7.1% of organic subjects did (Fisher's p < 0.001). The sign yielded a sensitivity of 100% (95% CI:84%-100%) and a specificity of 93% (95% CI:76%-98%). CONCLUSION: The observation of a "drift without pronation" sign is specific for Conversion Disorder and can be of help in making a quick distinction between organic and functional paresis at the bedside.

The characteristics of gait in Charcot-Marie-Tooth disease types I and II.

Certain typical gait characteristics such as foot-drop and foot supination are well described in Charcot-Marie-Tooth disease. These are directly related to the primary disease and due to the weakness of ankle dorsiflexors and everters characteristic of this hereditary neuropathy. We analysed 16 subjects aged 8-52 years old (11 with type I, 5 with type II Charcot-Marie-Tooth disease) using three-dimensional gait analysis and identified kinematic features previously unreported. These patients showed a combination of tight tendo achillei, foot-drop, failure of plantar flexion and increased foot supination, but also presented with excessive internal rotation of the knee and/or tibia, knee hyperextension in stance, excessive external rotation at the hips and decreased hip adduction in stance (typical of a broad based gait). These proximal features could have been an adaptation to or consequence of the disrupted ankle and foot biomechanics, however a direct relation to the neuropathy is also possible since sub-normal muscle power was observed at the proximal levels in most subjects on both manual testing and kinetic analysis. Gait analysis is a useful tool in defining the characteristic gait of patients with Charcot-Marie-Tooth disease.

Effects of isometric elbow flexion on electromyographic spike analysis

The main objective of this research was to examine the relationship between surface electromyographic (SEMG) spike activity and force. The secondary objective was to determine to what extent subcutaneous tissue impacts the high frequency component of the signal, as well as, examining the relationship between measures of SEMG spike shape and their traditional time and frequency analogues. A total of96 participants (46 males and 50 females) ranging in age (18-35 years), generated three 5-second isometric step contractions at each force level of 40, 60, 80, and 100 percent of maximal voluntary contraction (MVC). The presentation of the contractions was balanced across subjects. The right arm of the subject was positioned in the sagittal plane, with the shoulder and elbow flexed to 90 degrees. The elbow rested on a support in a neutral position (mid pronation/mid supination) and placed within a wrist cuff, fastened below the styloid process. The wrist cuff was attached to a load cell (JR3 Inc., Woodland, CA) recording the force produced. Biceps brachii activity was monitored with a pair of Ag/AgCI recording electrodes (Grass F-E9, Astro-Med Inc., West Warwick, RI) placed in a bipolar configuration, with an interelectrode distance (lED) of 2cm distal to the motor point. Data analysis was performed on a I second window of data in the middle of the 5-second contraction. The results indicated that all spike shape measures exhibited significant (p < 0.01) differences as force increase~ from 40 to 100% MVC. The spike shape measures suggest that increased motor unit (MU) recruitment was responsible for increasing force up to 80% MVC. The results suggested that further increases in force relied on MU III synchronization. The results also revealed that the subcutaneous tissue (skin fold thickness) had no relationship (r = 0.02; P > 0.05) with the mean number of peaks per spike (MNPPS), which was the high frequency component of the signal. Mean spike amplitude (MSA) and mean spike frequency (MSF) were highly correlated with their traditional measures root mean square (RMS) and mean power frequency (MPF), respectively (r = 0.99; r = 0.97; P < 0.01).

The impact of drug-induced dyskinesias on rapid alternating movements in patients with Parkinson's disease

We investigated the likelihood that hypokinesia/bradykinesia coexist with druginduced dyskinesias (DID) in patients with Parkinson's disease (PD). The influence of dyskinesias on rapid alternating movements (RAM) was investigated in ten dyskinetic patients (DPD). Their motor performance was compared to that of ten age/gendermatched non-dyskinetic patients (NDPD) and ten healthy control subjects. Whole-body magnitude (WBM) and fast pronation-supination at the wrist were recorded using 6- degrees of freedom magnetic motion tracker and forearm rotational sensors, respectively. Subjects were asked to pronate-supinate their dominant hand for 10s. Pre- and postmeasures were taken in a neutral position for 20s. RANGE (measure of hypokinesia), DURATION (measure of bradykinesia). VELOCITY (measure of bradykinesia) and IRREGULARITY (measure of fluctuations in movement amplitude) were used to assess RAM performance. Results showed that DPD patients had greater WBM than NDPD and control groups during rest and RAM performance. There were no differences in performance between NDPD and DPD groups for RANGE, DURATION and VELOCITY, despite significant longer disease duration for the DPD group (DPD = 15.5 ± 6.2 years versus NDPD = 6.6 ± 2.6 years). However, both the NDPD and DPD groups showed lower RANGE, longer DURATION, and reduced VELOCITY compared to controls,, suggesting the presence of bradykinesia and hypokinesia. In the case of IRREGULARITY, DPD patients showed clear fluctuations in movement amplitude compared to the NDPD and control groups. However, the lack of correlation between WBM and IRREGULARITY within the DPD group (Spearman's rank order, Rho - 0.31, p > 0.05), suggests that DID was not the primary cause of the fluctuating movementamplitude observed in that group. In conclusion, these findings suggest that DID may coexists with bradykinesia and hypokinesia, but that they are not inevitably accompanied with worsening motor performance.