Feasibility of low contrast volume and low injection flow rate in CT pulmonary angiography.

BACKGROUND: Computed Tomography Pulmonary Angiography (CTPA) is currently the gold standard for diagnosing Pulmonary Embolism (PE), with a high flowrate (>4.5ml/s) for contrast media (CM) administration recommended for sufficient pulmonary artery opacification. However, this may not be achievable for patients with challenging IV access. AIM: To determine if a low volume CM, low flowrate (LVLF) CTPA protocol produces images of similar image quality compared to a standard protocol in two aspects, in terms of peak arterial enhancement through the quantitative measurement of Hounsfield unit (HU) and based on subjective overall image quality. METHODS: Retrospective collection of 151 patients who underwent CTPA via 320 slice multi-detector CT due to clinical suspicion of PE. 80 patients underwent the standard protocol, with a fixed flowrate of 4.5ml/s and 50ml of CM, while 71 patients underwent the LVLF protocol with up to a 37% and 30% reduction in flowrate and CM administered, respectively. Two independent radiographers measured the attenuation of multiple pulmonary arteries in HU, with ≥200HU being considered diagnostic. Overall image quality was also reviewed using a 5-point close-ended questionnaire by two independent radiologists. RESULTS: There was no significant difference in terms of attenuation measured in HU for the seven regions of interest (main pulmonary trunk, right and left pulmonary arteries, right and left lobar arteries, and right and left subsegmental arteries (RSA and LSA)) between the LVLF and standard CTPA protocol. Similarly, there were no significant differences in the overall image quality score obtained from standard and LVLF protocols reported by both radiologists. CONCLUSION: The LVLF protocol can achieve similar enhancement and subjective image quality as the standard CTPA protocol, potentially allowing for further optimisation in the CM dosage.

The Influence of Kinesio Tape and an Ankle Brace on the Lower Extremity Joint Motion in Fatigued, Unstable Ankles during a Lateral Drop Landing.

BACKGROUND: An unstable ankle along with plantar flexor muscle fatigue may exacerbate landing performance. External support may be an option to control the ankle motion and protect joints from injuries. Research goal: To investigate the immediate changes in the joint motion of a lower extremity under ankle plantar flexors fatigue conditions in athletes with unstable ankles using different external supports. METHODS: A total of 44 participants were allocated to a control (Cn) group, an ankle brace (AB) group, and a kinesio tape (KT) group, and were asked to perform a lateral drop landing before and after a fatigue protocol. The outcome measures were fatigue-induced changes in the maximal joint angle and changes in the angle ranges of the hip, knee, and ankle. RESULTS: Smaller changes in the maximal hip abduction were found in the AB group (p = 0.025), and the KT group exhibited smaller changes in the maximal ankle dorsiflexion (p = 0.009). The AB group landed with a smaller change in the range of hip flexion and knee flexion (p = 0.008 and 0.006). The Cn group had greater fatigue-induced changes in the COM range than AB and KT group (p = 0.002 and 0.028). SIGNIFICANCE: Despite the beneficial effect in the postural control in the frontal plane, the use of AB might constrain the distal joint motion which might lead to an extended knee landing posture resulting in secondary injuries to the knee joint. Therefore, the use of AB in conjunction with an additional training of landing strategy might be recommended from the injury prevention perspective.

Effects of Different Ankle Supports on the Single-Leg Lateral Drop Landing Following Muscle Fatigue in Athletes with Functional Ankle Instability.

BACKGROUND: Ankle support has been utilized for athletes with functional ankle instability (FAI), however, its effect on the landing performance during muscle fatigue is not well understood. This study aimed to examine the effects of ankle supports (ankle brace vs. Kinesio tape) on athletes with FAI following fatigued single-leg landing. METHODS: Thirty-three young FAI athletes (CAIT scores < 24) were randomly allocated to control (Cn), ankle brace (AB) and Kinesio tape (KT) groups. All athletes performed single-leg lateral drop landings following ankle fatigue protocol. The fatigue-induced changes in kinetic parameters were measured among three groups. RESULTS: A significant increase in peak vertical ground reaction force (vGRF) was found in the AB group (0.12% body weight (BW)) compared to that of the KT (0.02% BW) and Cn (median = 0.01% BW) groups. Significant decrease in both COP medial-lateral (ML) and anterior-posterior (AP) ranges were also found in the KT group (median = -0.15% foot width (FW) & median = -0.28% foot length (FL)) than those of the Cn group (median = 0.67% FW& median = 0.88% FL). CONCLUSIONS: Ankle braces might hamper the ability to absorb the impact force during landing. On the other hand, Kinesio tape might be beneficial for the postural control during landing.

Accuracy of a modified axiolateral radiographic hip projection in suspected cases of hip fracture: experience and results from a regional trauma centre.

Conventional radiographs play an important role as a first line imaging modality in the assessment for suspected hip fractures in the majority of trauma centres. The routinely performed radiographic projections in our emergency department for patients with clinically suspected hip fractures include antero-posterior (AP) and cross-table lateral views of the affected hip. Certain clinical scenarios which include the presence of significant pain of the injured lower limb, a large patient habitus, as well as pre-existing patient morbidity which would limit the range of motion of the lower limbs, for example the presence of prior joint replacement surgery or lower limb contractures, may however preclude proper positioning of the patient to obtain an optimal cross-table lateral view of the affected hip. The objective of this study is to investigate whether a modified axiolateral hip projection would be a feasible alternative to the cross-table lateral projection in the initial radiographic assessment of suspected cases of hip fracture.

Fatigue-Induced Changes in Movement Pattern and Muscle Activity During Ballet Releve on Demi-Pointe.

Fatigue in ballet dancers may lead to injury, particularly in the lower extremities. However, few studies have investigated the effects of fatigue on ballet dancers' performance and movement patterns. Thus, the current study examines the effect of fatigue on the balance, movement pattern, and muscle activities of the lower extremities in ballet dancers. Twenty healthy, female ballet dancers performed releve on demi-pointe before and after fatigue. The trajectory of the whole body movement and the muscle activities of the major lower extremity muscles were recorded continuously during task performance. The results show that fatigue increases the medial-lateral center of mass (COM) displacement and hip and trunk motion, but decreases the COM velocity and ankle motion. Moreover, fatigue reduces the activities of the hamstrings and tibialis anterior, but increases that of the soleus. Finally, greater proximal hip and trunk motions are applied to compensate for the effects of fatigue, leading to a greater COM movement. Overall, the present findings show that fatigue results in impaired movement control and may therefore increase the risk of dance injury.

Fatigue-Induced Changes in Movement Pattern and Muscle Activity During Ballet Releve on Demi-Pointe.

Fatigue in ballet dancers may lead to injury, particularly in the lower extremities. However, few studies have investigated the effects of fatigue on ballet dancers' performance and movement patterns. Thus, the current study examines the effect of fatigue on the balance, movement pattern, and muscle activities of the lower extremities in ballet dancers. Twenty healthy, female ballet dancers performed releve on demi-pointe before and after fatigue. The trajectory of the whole body movement and the muscle activities of the major lower extremity muscles were recorded continuously during task performance. The results show that fatigue increases the medial-lateral center of mass (COM) displacement and hip and trunk motion, but decreases the COM velocity and ankle motion. Moreover, fatigue reduces the activities of the hamstrings and tibialis anterior, but increases that of the soleus. Finally, greater proximal hip and trunk motions are applied to compensate for the effects of fatigue, leading to a greater COM movement. Overall, the present findings show that fatigue results in impaired movement control and may therefore increase the risk of dance injury.