Welcome back for another installment of Research Bites! For all of you who missed my research posts on my Instagram (@science_of_falling), you came to the right place. Every few weeks I will be posting a new set of five quick and dirty research reviews with the main findings, how it was performed, and my quick take on it.

The trick is, I only have the space of an Instagram caption (2200 characters) to dive in and extract main points. It makes for a fun challenge! If you want to see these posts sooner, head on over to Instagram and hit that follow button.

Enjoy that tasty research!

Study Details

🔸27 recreationally active men (21.9 +/- 1.9 years old) with no known injury or health issues
🔸IFM muscle thickness, cross sectional area (CSA), and muscle hardness obtained with B-mode ultrasonography and real-time tissue elastography (RTE)
-Thickness and CSA of abductor hallucis (AbH), flexor hallucis brevis (FHB), flexor digitorum brevis (FDB) taken
-Hardness of AbH, FHB, and FDB measured using RTE in which varying levels of tissue compression was administered, as hardness of tissue increased RTE score decreased
🔸Single-leg standing test performed on stabilometer with eyes closed for 30s
-data for postural sway taken
-trial was repeated if participant lost balance
🔸Dynamic postural stability index (DPSI) and maximum vertical ground reaction force (vGRFmax) measured using a force plate
-Postural stability after landing evaluated after 2-leg jump and 1-leg landing in the forward direction
-Standardized 30cm jump height with a normalized jump distance 40% of the participants height
-Instructed to jump and land on force plate, stabilize, and hold for 10s
🔸Toe flexor strength taken with toe grip dynamometer

Study Findings

🔹Larger FDB (-) correlated with DPSI, but (+) correlated with anteroposterior stability (APS)
🔹RTE of the AbH (-) correlated with APS
🔹RTE of FDB (+) correlated with DPSI, vGRFmax, and vertical stability (VS)
🔹Thickness and CSA not correlated with DPSI
🔹RTE (+) correlated with DPSI

My Take 🤔

Essentially this study says hardness (how much a muscle will compress) of the FDB is (+) correlated with increased dynamic balance. The more your FDB is able to resist compression the more likely you are to have good dynamic balance. Opposite to this is AbH which showed less dynamic balance ability when increased hardness was present. Hardness in my mind is essentially level of muscle tone. So if we could find a way to increase tone of FDB and decrease tone of the AbH dynamic balance may be improved after jump landings.

Study Details

🔸27 healthy subjects (age 21.4 +/- 1.8 years; 19 males/10 females)
-no current lower extremity injury or history of surgery
🔸During study all subjects wore the same type of running shoe (Nike Air Pegasus 30)
🔸Subjects performed single-leg drop landing off 0.3m step with a natural landing (except for heel landing)
-Landed on force platform in addition to 8 camera motion capture system gathering data
-Landed on dominant foot and were instructed to balance for at least 2 seconds after landing
-Underwent two trials with results being averaged
🔸The joint angle at IC, joint ROM, joint angular velocity, peak vertical ground reaction force (vGRF), time to peak vGRF, peak loading rate, joint moment, joint power and joint energy dissipation at ankle, knee and hip joints of the dominant leg during landing obtained

Study Findings

🔹IC ankle angle mean value -11.5 deg +/- 13.1 deg; IC angle range of all participants -27.8 deg to 27.8 deg
🔹Ankle angle at IC (+) correlated with ankle negative work
🔹Ankle angle at IC (-) correlated with hip negative work
🔹Knee negative work not correlated with ankle at IC
🔹Ankle angle at IC (+) correlated with total negative work and (-) correlation with peak loading rates

My Take 🤔

The brass tacks of this study essentially says that during a single-leg landing having your toes pointed down further (more plantarflexion) leads to more force absorption (negative work). At the same time this reduces the body's force absorption at the hip joint. Overall the more plantarflexion utilized during landing, the less peak forces the body needs to handle. This may be why the hip does not need to absorb as much force via negative work during landing. Thus utilizing a soft landing during a jump/fall by extending all the leg joints (starting with the foot), such as a spring, leads to better force absorption and thus less injury risk. This type of landing is commonly seen in the sport of parkour.

Study Details

🔸593 preschool children, 303 girls and 290 boys, age 4.31 +/- 0.99 years (3-6 yo)
🔸No pathology noted in participants
🔸Underwent testing using the BBT
-BBT is a test of dynamic balance
-Subject walks on a 4cm x 12cm x 2.5m wood beam without shoes
-Subject walks from one end to the other and timed
-If the subject falls off, they resume from where they fell until task is completed
-Two trials performed with best trial taken as data
-Test score included: run time, steps performed, distance achieved
🔸Subjects also underwent a Stork test to evaluate static balance and convergent validity
-Stood without shoes, one foot balance, hands on hips, opposite foot placed on their knee
-Attempted to balance for up to one minute in this position
-Two attempts each leg with best score for each leg taken

Study Findings

🔹No significant differences found between sexes
🔹Age had positive effects on BBT performance in terms of distance and number of steps performed (showing better DB)
🔹Body height and body mass showed significant correlations with improved BBT performance as well, BUT did not correlate with BMI directly
🔹BBT showed good reliability and validity in the children 3-6 yo to monitor development of DB
🔹Norms for each age group in regards to distance, number of steps, and time available in study for those who wish to use this testing modality

My Take 🤨

If I had to boil this study down to one overarching finding it would be that balance control improves as children mature. In younger children postural adaptive strategies are not fine tuned, or even in place yet, that allow a child to control selective hip and trunk movements effectively. As a child ages, the ability to control these body regions independently may develop to a higher and more sophisticated degree leading to improved DB. The BBT may be a good tool to monitor a childs DB development as they mature.

Study Details

🔸62 patients with unilateral idopathic BPPV
-All had posterior or horizontal canal BPPV
-35 female/27 male, Avg age 45.3 yo
🔸Diagnosis of BPPV and side of lesion confirmed via patient history, Dix-Hallpike test, and head-roll test
-51 participants posterior canal BPPV, 11 lateral canal BPPV
-Only patients with straight forward unilateral BPPV allowed to partake in study
🔸FST performed prior to diagnostic testing
-Patient marched in one place with eyes closed for 50-100 steps
-Deviation from midline of about 45 degrees indicates a (+) test
-Patients split into two groups: Group 1 (G1) showed (+) FST test (33 participants), Group 2 (G2) showed (-) FST test (29 participants)
🔸After FST and diagnostic confirmation, patients underwent canalith repositioning manuevers (CRMs) to treat BPPV
-All patients examined once a week and CRM re-performed to those with no improvement
-Control examination and CRMs repeated until symptoms disappered
-Return of BPPV after 3 months of symptom free labeled as a recurrence

Study Findings

🔹No significant demographic differences between two groups
🔹In G1 No significant relation between (+) FST deviation side and BPPV side found
🔹G1 and G2 compared on number of CRMs to treat participants
-G1 had 33.3% treated with one CRM, and 67.7% needed multiple CRMs
-G2 had 68.9% treated with one CRM, and 31.3% needed multiple CRMs
🔹Need for multiple CRMs higher in (+) FST group (G1)
🔹G1 also had significantly higher recurrence rates of 57.6% vs. G2 of 31.1%

My Take 🤓

The FST was once thought to be a valuable part of diagnosing the side of a unilateral vestibular dysfunction. As this study shows, in concert with many other published studies, that may not be the case as there appears to be no defined pattern of (+) FST in relation to BPPV. What this study does show is that a (+) FST test may be indicative of a stubborn BPPV case that may require more CRMs and may reoccur.

Study Details

🔸Secondary data analysis of a cross-sectional study that assessed the risk factors of falls in older adults with diabetes
🔸Included older adults aged 65-80 years old with Type 2 diabetes from endocrine clinics in Taiwan
-total of 240 subjects: 147 female/93 male, mean age 70.85 yo
🔸Demographic and illness data collected including: age, sex, BMI, duration of illness, comorbiditys present, fall history, insulin treatment, any hypoglycemic events in the past year
🔸Chinese versions of the following questionnaires administered: Falls Efficacy Scale-International (FES-I), Problem Areas in Diabetes Scale (PADS) [Used to determine level of "diabetes distress"], Mini-Mental State Examination (MMSE), SARC-F (Strength, assistance with walking, rising from a chair, climbing stairs, and falls questionnaire)
🔸Physical testing included: Handgrip strength testing with dominant hand, Timed Up and Go (TUG), one legged standing balance time,

Study Findings

🔹Sex, age, lower education level, duration of diabetes, undergoing insulin treatment, HbA1c levels, experiencing a hypoglycemic episode in the past year, and fall history all were correlated with increased FoF
🔹Declining cognitive function, decreased handgrip strength, and decreased one-legged standing times, increased sarcopenia, slower TUG test, and higher levels of diabetes distress all associated with higher FoF
-Diabetes distress, sarcopenia levels, TUG test score, and HbA1c levels "explained 14%, 9%, 4%, and 2% of the variance in FoF respectiviely"

My Take 🤔

This study reports that poor coping skills, age related muscle loss, decreased dynamic balance, and poor blood sugar levels contribute to a higher fear of falling. The most significant contributor was the poor coping skills known as diabetes distress. This finding implies that not only should diabetic patients undergo physical training, but they should also recieve psychological therapy to increase coping skills to inversely decrease overall diabetes distress and thus lower FoF.

Thanks for reading the tenth volume of Research Bites! I hope you learned a tidbit or two. Be sure to follow my Instagram account to see these research bites right away, and comment below on what you think about the findings above.

Happy Falling!