Tadashi Ito

The Relationship between Physical Function and Postural Sway during Local Vibratory Stimulation of Middle-aged People in the Standing Position

[Purpose] The purpose of this study was to examine the relationship between physical function and postural sway during local vibratory stimulation of middle-aged subjects in an upright position. [Subjects] The subjects were 25 healthy community-dwelling middle-aged people. [Methods] We measured postural sway using a Wii board while vibratory stimulations of 30, 60, or 240 Hz were applied to the subjects’ lumbar multifidus or gastrocnemius muscles. Physical function was evaluated by 5-m usual gait speed and grip strength. [Results] Gait speed was strongly correlated to the anteroposterior body sway in the upright position during 30 Hz gastrocnemius muscles vibration (GMV). [Conclusion] Postural sway during 30 Hz GMV was strongly associated with gait speed and showed a posterior displacement. These findings show that the lower leg’s response to balance control under 30 Hz proprioceptive stimulation might be a good indicator of declining gait function.

Relationship between paraspinal muscle cross-sectional area and relative proprioceptive weighting ratio of older persons with lumbar spondylosis.

[Purpose] The purpose of this study was to examine the relationship between the paraspinal muscle cross-sectional area and the relative proprioceptive weighting ratio during local vibratory stimulation of older persons with lumbar spondylosis in an upright position. [Subjects] In all, 74 older persons hospitalized for lumbar spondylosis were included. [Methods] We measured the relative proprioceptive weighting ratio of postural sway using a Wii board while vibratory stimulations of 30, 60, or 240 Hz were applied to the subjects’ paraspinal or gastrocnemius muscles. Back strength, abdominal muscle strength, and erector spinae muscle (L1/L2, L4/L5) and lumbar multifidus (L1/L2, L4/L5) cross-sectional areas were evaluated. [Results] The erector spinae muscle (L1/L2) cross-sectional area was associated with the relative proprioceptive weighting ratio during 60Hz stimulation. [Conclusion] These findings show that the relative proprioceptive weighting ratio compared to the erector spinae muscle (L1/L2) cross-sectional area under 60Hz proprioceptive stimulation might be a good indicator of trunk proprioceptive sensitivity.

Postural Sway Response to Local Vibratory Stimulation in Young, Middle-aged and Elderly People in Standing Position

We investigated the postural sway in response to local vibratory stimulation applied to young, middle-aged and elderly people in the standing position. For this purpose we developed a variable-frequency vibratory stimulation device and measured the postural sway using a gravicorder. As a result, when the vibratory stimulation was applied to the gastrocnemius muscles, the center of pressure moved backward in all subject groups. We found that elderly people with low back pain may perform balance control using their trunks more than their lower legs.

Development of rehabilitation support system for lower limbs for recovery and quantitative evaluation of proprioception

Proprioception should be necessary for the trunk balance and skillful movement. However, proprioception deteriorates due to aging and spinal cord injury. Training for the recovery of proprioception is required because of the ADL and prevention of overturning. We have developed a new rehabilitation support system for “sensory training”. The purpose of this study is to perform clinical trials with 2 patients by using our system and discuss the results of clinical trials by analyzing the experimental data. In our system, video games are prepared as test programs for the proposed system. The measurements are performed one time before the operation and once or more until subjects are discharged from the hospital after the operation. In experiments, as the comparison studies, conventional quantitative evaluation tests, namely gravicorder test and 10 meter walking test are performed. As a result, this system plays a role of helping the patient with deteriorated proprioception to control lower limb as useful training tool based on the vision information feedback.

Identification and purification of Ca2+/calmodulin-dependent protein kinase V from human gastric carcinoma.

We previously purified a novel Ca2+/calmodulin-dependent protein kinase (CaM kinase) V, which has proven to be a member of the CaM kinase I family. Immunohistochemical staining of surgically-resected specimens from human subjects using specific antibody which reacts with CaM kinases I and V demonstrated heterogeneous distribution of CaM kinase I/V in normal gastric mucosa. The kinase was located mainly at the bottom of foveoral epithelium and in the gastric gland (< 25% immunopositive). In contrast, this kinase was abundant in various types of gastric carcinomas (> 75%), but not in gastric adenomas. Preferential and consistent presence of this kinase was confirmed by immunoblot analysis of gastric carcinoma and human gastric cancer cell lines, Kato-III and MKN-45. CaM kinase I/V was co-purified with CaM kinase II from resected gastric carcinoma using anion-exchange chromatography followed by calmodulin-affinity chromatography. The two kinases were finally separated by HPLC-based gel filtration. Purified CaM kinase I/V from gastric carcinoma did not possess detectable autophosphorylating activity, in contrast to CaM kinase II. The findings suggest CaM kinase I/V may possess abnormal biochemical properties in human gastric carcinoma, and the kinase could participate in cell growth of the carcinoma.

Correlation between the Gait Deviation Index and skeletal muscle mass in children with spastic cerebral palsy

[Purpose] This study aimed to identify a simple and useful muscle parameter for use with the Gait Deviation Index in assessment of ambulatory children with unilateral and bilateral spastic cerebral palsy. [Participants and Methods] Twenty-eight patients (aged 6 to 18 years; 16 females and 12 males) participated in this cross-sectional study. Outcome measurements included the Gait Deviation Index, grip strength, 5-repetition chair stand test, upper limb skeletal muscle mass index, and lower limb skeletal muscle mass index. [Results] By multiple regression analysis, significant independent correlations were observed between the Gait Deviation Index and 5-repetition chair stand test and the Gait Deviation Index and lower limb skeletal muscle mass index, but not between the Gait Deviation Index and grip strength or upper limb skeletal muscle mass index. [Conclusion] The Gait Deviation Index was correlated with lower limb muscle mass in children with spastic cerebral palsy. Determination of lower limb muscle mass may be useful gait evaluation.

Proprioceptive change impairs balance control in older patients with low back pain

[Purpose] This study aims to determine the specific proprioceptive control strategy used during postural balance in older patients with low back pain (LBP) and non-LBP (NLBP) and to assess whether this strategy is related to proprioceptive decline and LBP. [Subjects and Methods] Pressure displacement center was determined in 47 older persons with LBP and 64 older persons with NLBP during upright stance on a balance board without vision. Gastrocnemius (GS) and lumbar multifidus muscle (LM) vibratory stimulations of 60 and 240-Hz, respectively, were applied to evaluate the relative contributions of different proprioceptive signals (relative proprioceptive weighting ratio, RPW) used in postural control. Age, height, weight, back muscle strength, L1/2 and L4/5 lumbar multifidus cross section area ratio, skeletal muscle mass index, sagittal vertical axis, and Roland-Morris disability questionnaire (RDQ) were evaluated. [Results] Compared with older patients with NLBP, those with LBP showed a lower RPW 240-Hz, lower L4/5 lumbar multifidus cross-sectional area ratio, and a significantly higher age and RDQ. Logistic regression analysis showed that RPW 240-Hz and age were independently associated with LBP, after controlling for confounding factors. [Conclusion] Older patients with LBP decreased their reliance on GS (RPW 240-Hz) proprioceptive signals during balance control.