Kenneth Bo Foreman

Testing balance and fall risk in persons with Parkinson disease, an argument for ecologically valid testing

INTRODUCTION Despite clear deficits in postural control, most clinical examination tools lack accuracy in identifying persons with Parkinson disease (PD) who have fallen or are at risk for falls. We assert that this is in part due to the lack of ecological validity of the testing. METHODS To test this assertion, we examined the responsiveness and predictive validity of the Functional Gait Assessment (FGA), the Pull test, and the Timed up and Go (TUG) during clinically defined ON and OFF medication states. To address responsiveness, ON/OFF medication performance was compared. To address predictive validity, areas under the curve (AUC) of receiver operating characteristic (ROC) curves were compared. Comparisons were made using separate non-parametric tests. RESULTS Thirty-six persons (24 male, 12 female) with PD (22 fallers, 14 non-fallers) participated. Only the FGA was able to detect differences between fallers and non-fallers for both ON/OFF medication testing. The predictive validity of the FGA and the TUG for fall identification was higher during OFF medication compared to ON medication testing. The predictive validity of the FGA was higher than the TUG and the Pull test during ON and OFF medication testing. DISCUSSION In order to most accurately identify fallers, clinicians should test persons with PD in ecologically relevant conditions and tasks. In this study, interpretation of the OFF medication performance and use of the FGA provided more accurate prediction of those who would fall.

The 9-hole PEG test of upper extremity function: Average values, test-retest reliability, and factors contributing to performance in people with Parkinson disease

Background and Purpose: Pegboard tests of hand dexterity are commonly used in clinical settings to assess upper extremity function in various populations. For individuals with Parkinson disease (PD), the clinical utility of pegboard tests has not been fully evaluated. Our purpose was to examine the commercially available 9-Hole Peg Test (9HPT) using a large sample of individuals with PD to determine average values, test-retest reliability, and factors predictive of 9HPT performance. Methods: A total of 262 participants with PD (67% men, Hoehn & Yahr stage = 2.3 ± 0.7) completed the 9HPT along with a battery of other tests including the Movement Disorder Society Unified PD Rating Scale—Motor Subscale III and Freezing of Gait Questionnaire. Results: Average time to complete the 9HPT was 31.4 ± 15.7 s with the dominant and 32.2 ± 12.4 s with the nondominant hand. Test-retest reliability of 2 trials performed with the same hand was high (dominant ICC2,1 = 0.88, nondominant ICC2,1 = 0.91). Women performed the test significantly faster than men, and nonfreezers significantly faster than freezers. For either hand, age, bradykinesia, and freezing of gait scores individually predicted significant portions of the variance in 9HPT time. Sex also was a significant predictor, but for the nondominant hand only. Tremor and rigidity did not predict performance. Discussion and Conclusions: The 9HPT appears to be a clinically useful measure for assessing upper extremity function in individuals with PD. The 9HPT has advantages over previously used methods including standardization, known normative values for healthy controls, commercial availability, transportability, and ease of administration.

Charting the progression of disability in parkinson disease: study protocol for a prospective longitudinal cohort study

BackgroundPeople with Parkinson disease (PD), even in the presence of symptomatic relief from medical, surgical, and rehabilitative interventions, face a persistent worsening of disability. This disability is characterized by diminished quality of life, reduced functional mobility, declining performance in activities of daily living and worsening neurological impairments. While evidence has emerged supporting the clinically meaningful benefits of short-term exercise programs on these underlying factors, assertions regarding the effects of sustained programs of exercise and physical activity on the trajectory of disablement in PD are made in the absence of direct evidence. Indeed, the natural decline in quality of life and functional mobility in people diagnosed with PD is poorly understood. Moreover, outcome measures commonly used in clinical exercise trials typically do not capture the full spectrum of disability as defined by the World Health Organization (WHO).Methods/DesignThe objective of this multicenter prospective study will be to examine the 2-year trajectory of disablement in a cohort of persons with PD. Two hundred sixty participants will be recruited to produce an expected final sample size of 150 individuals. Participants will be included if they are greater than 40 years of age, have a neurologist confirmed diagnosis of idiopathic PD, and are at Hoehn and Yahr stages 1 through 4. Data will be collected every 6 months during the study period. Primary outcome measures reflecting a broad spectrum of disablement will include, but will not be limited to, MDS-UPDRS, Timed Up and Go, Berg Balance Test, Nine Hole Peg Test, PDQ-39, and directly monitored ambulatory activity. Self-reported exercise and physical activity data also will be recorded. Statistical analyses will be used to characterize the trajectory of disablement and examine the influence of its underlying contributing factors.DiscussionTertiary prevention is an important component of contemporary healthcare for individuals living with degenerative disease. For individuals with PD, there is growing recognition that exercise and/or physical activity efforts to slow the rate of functional mobility decline, in particular, may be critical for optimizing quality of life. By describing the natural trajectory of disablement, exercise habits, and physical activity in a cohort of persons with PD, this investigation will establish an important foundation for future intervention research. Specifically, through the evaluation of the influence of sustained exercise and physical activity on disablement, the study will serve as a preliminary step toward developing a randomized controlled trial of long-term exercise in persons with PD.

Predictors of gait speeds and the relationship of gait speeds to falls in men and women with Parkinson disease.

Gait difficulties and falls are commonly reported in people with Parkinson disease (PD). Reduction in gait speed is a major characteristic of Parkinsonian gait, yet little is known about its underlying determinants, its ability to reflect an internal reservation about walking, or its relationship to falls. To study these issues, we selected age, disease severity, and nonmotor factors (i.e., depression, quality of life, balance confidence, and exercise beliefs and attitudes) to predict self-selected (SELF), fast-as-possible (FAST), and the difference (DIFF) between these walking speeds in 78 individuals with PD. We also examined gender differences in gait speeds and evaluated how gait speeds were related to a retrospective fall report. Age, disease severity, and balance confidence were strong predictors of SELF, FAST, and, to a lesser extent, DIFF. All three parameters were strongly associated with falling. DIFF was significantly greater in men compared to women and was significantly associated with male but not female fallers. The results supported the clinical utility of using a suite of gait speed parameters to provide insight into the gait difficulties and differentiating between fallers in people with PD.

Does Dopamine Replacement Medication Affect Postural Sequence Learning in Parkinson’s Disease?

The aim of this study was to examine (1) the temporal structures of variation in rowers’ (natural) ergometer strokes to make inferences about the underlying motor organization, and (2) the relation between these temporal structures and skill level. Four high-skilled and five lower-skilled rowers completed 550 strokes on a rowing ergometer. Detrended Fluctuation Analysis was used to quantify the temporal structure of the intervals between force peaks. Results showed that the temporal structure differed from random, and revealed prominent patterns of pink noise for each rower. Furthermore, the high-skilled rowers demonstrated more pink noise than the lower-skilled rowers. The presence of pink noise suggeststhat rowing performance emerges from the coordination among interacting component processes across multiple time scales. The difference in noise pattern between high-skilled and lower-skilled athletes indicates that the complexity of athletes’ motor organization is a potential key characteristic of elite performance.Deficits in sequence-specific learning (SSL) may be a product of Parkinsons disease (PD) but this deficit could also be related to dopamine replacement. The purpose of this study was to determine whether dopamine replacement affected acquisition and retention of a standing Continuous Tracking Task in individuals with PD. SSL (difference between random/repeated Root Mean Square Error across trials) was calculated over 2 days of practice and 1 day of retention for 4 groups; 10 healthy young (HY), 10 healthy elders, 10 individuals with PD on, 9 individuals with PD off their usual dosage of dopamine replacement. Improvements in acquisition were observed for all groups; however, only the HY demonstrated retention. Therefore, age appeared to have the largest effect on SSL with no significant effect of medication. Additional research is needed to understand the influence of factors such as practice amount, task difficulty, and dopamine replacement status on SSL deficits during postural tasks.

Improved Dynamic Postural Task Performance without Improvements in Postural Responses: The Blessing and the Curse of Dopamine Replacement.

Introduction. Dopamine-replacement medications may improve mobility while not improving responses to postural challenges and could therefore increase fall risk. The purpose of this study was to measure reactive postural responses and gait-related mobility of patients with PD during ON and OFF medication conditions. Methods. Reactive postural responses to the Pull Test and performance of the Functional Gait Assessment (FGA) were recorded from 15 persons with PD during ON and OFF medication conditions. Results. Persons with PD demonstrated no significant difference in the reactive postural responses between medication conditions but demonstrated significantly better performance on the FGA when ON medications compared to OFF. Discussion/Conclusion. Dopamine-replacement medications alone may improve gait-related mobility without improvements in reactive postural responses and therefore could result in iatrogenic increases in fall risk. Rehabilitation providers should be aware of the side effects and limitations of medication treatment and implement interventions to improve postural responses.

Morphometry of the lower lumbar intervertebral discs and endplates: comparative analyses of new MRI data with previous findings

PurposeVariability of the human lower lumbar geometry is related to complications of disc arthroplasty surgery. Accurate morphometric descriptions are essential for the design of artificial intervertebral discs to ensure good prothesis-vertebra contact and better load distribution, and can improve spinal biomechanics. Unfortunately, current knowledge of the lower lumbar geometry is limited either in the representativeness of sample populations or the accuracy and comprehensiveness of measurements. The objective of this study was to establish an accurate and reliable measurement protocol, provide a comprehensive database of lower lumbar geometry, and compare and summarize geometric data as reported in the literature.MethodsT2-weighted magnetic resonance imaging (MRI) scans of lower lumbar spine (L3–S1), taken from 109 adult subjects, were anonymized from the digital archive of a local hospital. A total of 318 intervertebral discs and 590 endplates met the inclusion criteria and were studied. Linear and planar measurements were performed using OsiriX software, and analyzed using split plot factorial (SPF) analysis of variance (ANOVA), independent student t tests, paired sample t tests, and Tukey’s honest significant difference (HSD) post hoc tests.ResultsExcellent intra- and inter-observer reliabilities were achieved using the proposed measurement protocol. The results of this study indicated that male subjects had significantly larger geometric dimensions. L5/S1 discs had the smallest geometric dimensions compared to the discs at other two levels. Significant craniocaudal differences were found in endplate morpohometry. The error associated with using ellipsoid methods was quantified at each lower lumbar level. A large comprehensive database compiling lower lumbar geometry from many studies was established. This study provides geometric data for the female subjects at the L5/S1 level, previously lacking in the literature.ConclusionThis study demonstrates the potential of using MRI data to establish a standard measurement protocol for morphometric quantification of the lower lumbar intervertebral discs and vertebral endplates. These results are invaluable in characterizing comprehensive lower lumbar morphometry, which may provide crucial information for planning spinal surgeries, designing artificial intervertebral discs, and for biomechanical modeling of the low lack.

Quadriceps weakness preferentially predicts detrimental gait compensations among common impairments after total knee arthroplasty: QUADRICEPS WEAKNESS INFLUENCES JOINT MECHANICS

Patients with total knee arthroplasty (TKA) have large deficits in physical performance in comparison to their healthy age‐matched peers. Limb asymmetry stemming from less relative load borne by the surgical limb during daily mobility is associated with diminished performance and worsens with greater mobility demands. How common targets of postoperative care, such as muscle weakness, lower limb extension power, residual knee pain, and poor balance confidence can influence asymmetrical limb loading remains unclear. Forty‐six patients with unilateral TKA underwent testing of impairments and motion analysis during 10° decline walking at 3 and 6 months postoperatively. At 3 months, only quadriceps femoris strength asymmetry was found to be significantly related to both total support moment (MT) (β = 0.431; p < 0.001) and knee extensor moment (MK) (β = 0.493; p < 0.001) asymmetry. Again at 6 months, only quadriceps strength asymmetry was related to MT (β = 0.432; p < 0.001) and MK (β = 0.534; p < 0.001) asymmetry. Quadriceps strength significantly improved over time in both limbs, however, deficits between limbs remained. Persistent quadriceps weakness is a key factor associated with walking compensation patterns that are limiting the capacity for greater physical performance of patients with TKA. The pronounced asymmetry in limb and knee loading at 3 months remains unchanged until at least 6 months after surgery, and its association with quadriceps strength asymmetry does not substantially change over time. While other factors may also prompt gait compensations, emphasis on improved quadriceps strength should be a focus of efforts to resolve gait compensations and enhance physical performance outcomes.

Validity and Reliability of Two-Dimensional Motion Analysis for Quantifying Postural Deficits in Adults With and Without Neurological Impairment.

Frequently, clinical balance outcome measures are limited by floor or ceiling effects and provide insufficient resolution to determine subtle deficits. Detailed assessment of postural control obtained through posturography may be cost‐prohibitive or logistically infeasible in some clinical settings. Two‐dimensional (2D) motion analysis may provide a clinically feasible means of obtaining detailed quantification of balance deficits. Forty‐five participants aged 18–80 years, with and without Parkinson disease, performed the Push and Release (PR) test, sit‐to‐stand (STS), and timed single leg stance (SLS). Performance was captured simultaneously using a three‐dimensional (3D) (10‐camera laboratory‐based 3D motion capture system and 3D motion analysis software) and 2D (two commercially available video cameras and 2D motion analysis software) system. Agreement was excellent between 2D and 3D systems for all outcomes of the PR and SLS (intraclass correlation coefficients [ICC2,1] 0.96–0.99, 95% CIs 0.92–0.98 to 0.99–1.0), and ranged from fair to excellent for STS outcomes (ICC2,1 0.59–0.93, 95% CIs 0.36–0.75 to 0.87–0.96). Test–retest reliability (ICC3,1 0.89–1.0, 95% CIs 0.76–0.96 to 1.0–1.0) and inter‐rater reliability (ICC2,1 0.77–1.0, 95% CIs 0.61–0.87 to 1.0–1.0) of the 2D obtained outcomes were excellent. A technology package of commonly available video cameras and 2D motion analysis software was a valid and reliable method for quantifying outcomes of postural control tasks in people with a range of balance abilities. Two‐dimensional analysis can be used in clinical practice to provide balance assessments as a cost‐effective alternative to 3D motion capture. Anat Rec, 299:1165–1173, 2016.

Editor's-Choice Symposium: The Anatomical Record Replaces Wonder With Knowledge: Editor's Choice Editorial

Ever since my (KA, first author of this Editorial) reading of Jules Verne’s “Twenty Thousand Leagues Under the Sea” (1872) and Herman Melville’s “Moby Dick” (“The Whale”) (1851), I wondered about whales. However, growing up in suburban Chicago, most of my childhood wonders were landlocked. Instead, I grew to learn about the alewife (Alosa pseudoharengus), a nonnative relative of the lowly, North American shad that invaded the cold waters of Lake Michigan. My memory from the 1970s is stench caused by mass deaths of these alien fish owing to their population explosion during the 1960s. Indeed, our 1975 honeymoon was befouled by the gag-inducing odor of thousands of dead alewives pushed ashore by the waves along Sheboygan, Wisconsin’s shoreline. So off-putting was the odor that flooded the Lake Michigan cabin at which we stayed that we eschewed romantic lakeside walks, instead fleeing to the local movie theaters to watch the new summer block-Buster, “The Apple Dumpling Gang,” starring “legends” Don Knots, Bill Bixby, Susan Clark, Tim Conway, Slim Pickens among others. Ah, the memorable moments of initial married life! Over the years, we shifted our viewing interest to whales in the oceans of the world. We touched newborn California gray whales that were pushed up by their mothers from the birthing waters of San Ignacio Lagoon, in Baja Sur, Mexico. We connected with Melville’s epic story by watching and listening to sperm whales surface from the fathoms to exhale and take fresh breathes, with giant squid tentacles still wriggling from the whales’ mouths, all from the vantage point above the edge of the continental shelf that is about a mile off-shore of Kaikoura, New Zealand. We also whale-watched from Hermanus, South Africa, where we watched Southern Right whales at play. These experiences whet our appetite but left us wanting more knowledge to enhance our youthful wonder. The Anatomical Record brought an amazing, handson, learning experience for coauthors of this editorial when, in April of 2012, chance-opportunity knocked at our and the Journal’s doors. While at the annual meeting of Experimental Biology in San Diego, a call came out that the head of a neonatal female California gray whale (Eschrichtius robustus; SDNHM 24307) was to be dissected at San Diego State University. The neonate stranded at Moss Landing, Monterey County, CA. Veterinarians determined that the neonatal whale would not survive if returned to the ocean so decision was made to humanely euthanize it. The scientific opportunity to study anatomy of the neonatal gray whale was important because access to neonatal whales is rare. Whale experts Drs. Annalisa Berta, Eric Ekdale, and Ted Cranford from San Diego State University, Tom Dem er e from the San Diego Natural History Museum, and Joy Reidenberg from Mt. Sinai School of Medicine, along with a handful of the rest of us, participated in dissection of the whale’s head. From this unique, hands-on opportunity to dissect the head came a Thematic Papers issue of The Anatomical Record that has six papers reporting the discoveries made (Berta et al., 2015a; Laitman, 2015). Observations are described on the external anatomy of the head (Berta et al., 2015b), oral anatomy (Kienle et al., 2015), tongue vasculature (Ekdale and Kienle, 2015), temporomandibular joint and muscles that act on the joint (El Adli and Demere, 2015), vasculature of the palate (Ekdale et al., 2015), and morphometrics of complete baleen racks (Young et al., 2015). These unique reports add to the rich tradition of whale papers that are regularly published in the Journal (Laitman and Albertine, 2015), including a most notable 2007 Special Issue on Anatomical Adaptations of Aquatic Mammals, guest edited Joy Reidenberg. These experiences led to an idea: members of the editorial board of The Anatomical Record should have similar opportunity to replace wonder with knowledge by having a scientific activity during the editorial board’s annual meeting. Our concept’s implementation is dubbed “Editor’s-Choice Symposium” at the editorial board’s annual meeting and from which thematic articles are recruited for the Journal. To our knowledge, such a scientific scholarly activity embedded in an annual editorial board meeting is another “first” by The Anatomical Record. The venue for this, the inaugural, Editor’s-Choice Symposium was the Strait of Georgia west of Vancouver, BC. We took a whale-watch cruise to observe orcas and possibly humpback whales. Embarkation was from the nearby port town of Richmond (Steveston). We recruited local whale THE ANATOMICAL RECORD 300:1917–1929 (2017)