Repetitive shock wave therapy improves muscular microcirculation.

BACKGROUND: Extracorporeal shock wave therapy (ESWT) is mainly applied in tendon as well as bone problems based on stem-cell activation and healing acceleration. The effect of ESWT on muscle tissue is much less understood to date. However, from a clinical perspective, muscle injuries are of distinct interest especially in elite athletes such as soccer players. MATERIAL AND METHODS: A total of 26 rats were randomized into two groups. Group A received a single application of high-energetic focused ESWT (0.3 mJ/mm(2), 4 Hz, 1000 impulses, 10 J), whereas group B underwent the same procedure every 10 min for three sessions (3 × 0.3 mJ/mm(2), 4 Hz, 3 × 1000 impulses, totaling 30 J). Blood flow at a depth of 8 mm was measured continuously and noninvasively by a combined Laser-Doppler-Imaging and photospectrometric technique (Oxygen-to-see, O2C, LEA Medizintechnik, Germany). RESULTS: One minute after the application of high-energy ESWT blood flow in group A increased by 16.5% (P = 0.007). Thereafter, it decreased from minute 2 after application and remained significantly unchanged to baseline value until the end of the measuring period at 50 min (P = 0.550). Group B showed a similar significant increase in blood flow of 16.4% (P = 0.049) and a decrease afterward, too. After the second focused ESWT blood flow was boosted to 26.6% (P = 0.004), remaining significantly elevated until the third application was initiated. Muscular blood flow was increased to 29.8% after the third focused ESWT (P < 0.001), remaining significantly increased for another 10 min. CONCLUSIONS: Focused ESWT enhances blood flow in the muscle of rats. Moreover, repetitive ESWT extended this beneficial effect.

Deeper Cochlear Implant Electrode Insertion Angle Improves Detection of Musical Sound Quality Deterioration Related to Bass Frequency Removal.

BACKGROUND: Cochlear implant (CI) electrode arrays typically do not reach the most apical regions of the cochlea that intrinsically encode low frequencies. This may contribute to diminished implant-mediated musical sound quality perception. The objective of this study was to assess the effect of varying degrees of apical cochlear stimulation (measured by angular insertion depth) on musical sound quality discrimination. HYPOTHESIS: Increased apical cochlear stimulation will improve low-frequency perception and musical sound quality discrimination. METHODS: Standard (31.5 mm, n = 17) and medium (24 mm, n = 8) array Med-EL CI users, and normal hearing (NH) listeners (n = 16) participated. Imaging confirmed angular insertion depth. Participants completed a musical discrimination task in which they listened to a real-world musical stimulus (labeled reference) and provided sound quality ratings to versions of the reference, which included a hidden reference and test stimuli with increasing amounts of low-frequency removal. Scores for each CI users were calculated on the basis of how much their ratings differed from NH listeners for each stimulus version. RESULTS: Medium array and standard users had significantly different insertion depths (389.4 ± 64.5 and 583.9 ± 78.5 degrees, respectively; p <  .001). A significant Pearson's correlation was observed between angular insertion depth and the hidden reference scores (p < 0.05). CONCLUSION: CI users with greater apical stimulation made sound quality discriminations that more closely resembled those of NH controls for stimuli that contained low frequencies (< 200 Hz of information). These findings suggest that increased apical cochlear stimulation improves musical low-frequency perception, which may provide a more satisfactory music listening experience for CI users.

Impact of diabetes and peripheral arterial occlusive disease on the functional microcirculation at the plantar foot.

BACKGROUND: Plastic and reconstructive surgeons are commonly faced with chronic ulcerations and consecutive wound infections of the feet as complications in patients with diabetes and/or peripheral arterial occlusive disease (PAOD). Microcirculatory changes seem to play an important role. However, the evaluation of functional changes in the soft tissue microcirculation at the plantar foot using combined Laser-Doppler and Photospectrometry System has not yet been performed in patients with DM or PAOD. METHODS: A prospective, controlled cohort study was designed consisting of a total of 107 subjects allocated to 1 of 3 groups-group A: healthy subjects (57% males, 63.3 y); group B: patients with diabetes mellitus (DM) (53% males, 59.4 y); and group C: patients with PAOD (81% males, 66.1 y). Microcirculatory data were assessed using a combined Laser-Doppler and Photospectrometry System. RESULTS: Global cutaneous oxygen saturation microcirculation at the plantar foot of healthy individuals was 8.4% higher than in patients with DM and 8.1% higher than in patients with PAOD (both P = 0.033). Patients with diabetes did not show significant differences in global cutaneous blood flow when compared with either healthy subjects or patients suffering from PAOD. CONCLUSIONS: Functional microcirculation at the plantar foot differs between healthy subjects and patients suffering from diabetes or PAOD of the same age. Patients with either diabetes or PAOD demonstrate deteriorated cutaneous oxygen saturation with equivalent blood perfusion at the plantar foot. More clinical studies have to be conducted to evaluate therapeutical methods that might ameliorate cutaneous oxygen saturation within diabetic foot disease and PAOD.

Analysis of hereditary and medical risk factors in Achilles tendinopathy and Achilles tendon ruptures: a matched pair analysis.

OBJECTIVE: In Achilles tendon injuries, it is suggested that a pathological continuum might be evident from the healthy Achilles tendon to Achilles tendinopathy to Achilles tendon rupture. As such, risk factors for both tendinopathy and rupture should be the same. HYPOTHESIS: Hereditary and medical risk factors for Achilles tendinopathy and Achilles tendon rupture are the same to a similar extent in a matched pair analysis. DESIGN: Matched pair study; level of evidence: 3. SETTING: Recreational sportsmen as well as athletes on national level. PATIENTS: 566 questionnaires were analysed. 310 subjects were allocated to 3 groups (A, B, C) after matching the pairs for age, weight, height and gender: (A) healthy Achilles tendons (n = 89, age 39 ± 11 years, BMI 25.1 ± 3.9, females 36%), (B) chronic Achilles tendinopathy (n = 161, age 41 ± 11 years, BMI 24.4 ± 3.7, females 34%), (C) acute Achilles tendon rupture (n = 60, age 40 ± 9 years, BMI 25.2 ± 3.2, females 27%). RESULTS: We found a positive family history of Achilles tendinopathy as a risk factor for Achilles tendinopathy (OR: 4.8, 95% CI: 1.1-21.4; p = 0.023), but not for Achilles tendon rupture (OR: 4.0, 95% CI 0.7-21.1, p = 0.118). Smoking and cardiac diseases had a lower incidence in Achilles tendinopathy than in healthy subjects (both p = 0.001), while cardiovascular medication did not change the risk profile. CONCLUSION: Identifying risk factors associated with Achilles tendon disorders has a high clinical relevance regarding the development and implementation of prevention strategies and programs. This cross-sectional study identified a positive family history as a significant solitary risk factor for Achilles tendinopathy, increasing the risk fivefold. However, in this matched pair analysis excluding age, weight, height and gender as risk factors no further factor necessarily increases the risk for either Achilles tendinopathy or Achilles tendon rupture.