Changes in static balance during pregnancy and postpartum: A systematic review

The role of waddling gait in balance control during pregnancy

BACKGROUND

Pregnant people experience many physical changes which might affect their walking pattern. Waddling gait is a common gait pattern pregnant individuals adopt. It is unknown whether waddling gait is a sign of poor balance or a protective mechanism against loss of balance, so the aim of this study was to understand why some pregnant individuals adopt this gait pattern.

METHODS

We assessed twenty-three pregnant individuals longitudinally in 4-week intervals between 18 and 34 weeks of gestation. Participants completed a quiet standing balance trial and a walking trial. We measured spatiotemporal variables and body center of mass motion, from which we derived measures of balance and gait energetics. Forward-step multiple linear regression analyses were used to explore the correlation between step width (as a measure of waddling) and the other variables.

RESULTS

We found a positive correlation between change in step width average and change in lateral motion of the center of mass during walking (R2=0.624, P<0.001) and change in step width standard deviation and change in minimum center of gravity distance to the lateral border (R2=0.339, p=0.004), suggesting wider steps help recapture balance during pregnancy. Surprisingly, no significant relationship was found between change in step width and changes in energy recovery (p=0.341) or mechanical work (p=0.482), indicating that taking wider steps is not inefficient. A negative correlation between change in step width and change in standing anteroposterior center of mass motion (R2=0.315, p=0.005) suggests better balance control among people that adopt a waddling gait pattern.

SIGNIFICANCE

This study suggests that waddling gait is a protective mechanism during pregnancy. Clinicians and prosthetists can use this insight to promote step width during walking among pregnant individuals to increase their safety.

Postural control patterns in gravid women-A systematic review

BACKGROUND

Postural stability is essential for functional independence in the pregnant population. The contradictions between existing studies and the lack of consistent characteristics in the strategies used by pregnant women for postural control demonstrate the need for further investigation.

OBJECTIVES

The aim was to review the available literature on postural strategies throughout pregnancy in both static and dynamic conditions and to provide an assessment of the quality of these studies in terms of methodological issues to identify the reasons for the inconsistencies in findings between research centers.

METHODS

Literature searches were conducted using PubMed and EBSCOhost Research Databases. The latest search was performed on September 01, 2024. The review was restricted to longitudinal, cross-sectional, case-control, and descriptive studies focused on the effect of pregnancy on the stability of future mothers, with the following criteria: healthy pregnant women and singleton pregnancies. Trials were excluded if they were restricted to multiple pregnancies or considered various kinds of interventions. The methodological quality was evaluated using the criteria proposed by Downs and Black. Data items such as information on study design, characteristics of the study sample, equipment used, stability task performance, and outcome measures were presented.

RESULTS

The final analysis comprised 22 articles, including a total of 641 pregnant and 296 nonpregnant women. Research results in both static and dynamic conditions are inconclusive, showing either a decrease, no change, or improvement in postural equilibrium as pregnancy advances. Importantly, the results indicate that women in advanced pregnancy may be at increased risk of falling when their vision is compromised.

DISCUSSION

A lack of homogeneity in the study groups and a small number of longitudinal analyses were observed. The methodologies applied and the postural indices used to measure body sway varied across the studies. Our findings can serve as basic data for health promotion programs to encourage safe daily activities in pregnant women.

Balance in obese and normal weight pregnant women: A longitudinal study

INTRODUCTION

Pregnancy's physiological changes and weight gain can decrease balance control, increasing the risk of falls and impacting quality of life. The effect of obesity on balance control in pregnant women needs further investigation.

OBJECTIVE

Investigate the effect of obesity during pregnancy on center of pressure (COP) control under sensory disturbances at different gestational age.

METHODS

The COP (95% ellipse area, mean velocity and total length) of 23 pregnant women classified as normal weight (CG: n = 12) and obese (OG: n = 11) was evaluated at three gestational-age week times (T1 = 16th, T2 = 24th, T3 = 32nd week) on a force platform on standing position (SP) and under three disturbances: 1) visual disturbance (eyes closed), 2) proprioceptive disturbance (over an unstable surface) and, 3) vestibular disturbance (head movement). A mixed ANOVA (3 repeated measures vs. 2 groups) and LSD post-hoc was applied to examine main effects and interactions. Effect sizes were assessed using generalized eta squared (η2).

RESULTS

As main effect, in SP, COP area increased from T2 to T3 for both groups (P = 0.021, η2 = 0.193). One interaction was observed, under visual disturbance, the area increased from T2 to T3 only in the CG group (P = 0.020, η2 = 0.195).

CONCLUSION

The progression of pregnancy negatively impacts postural stability throughout its course. Visual disturbance only affected the balance of the CG. Hence, obesity combined with pregnancy does not appear to alter COP variables.

Long-term gait analysis in patients after total knee arthroplasty: A systematic review and meta-analysis

BACKGROUND

Gait abnormalities have been described in patients after total knee arthroplasty (TKA), leading to the development of inter-joint coordination abnormalities and increased risk of falling. Such impairments have been reported to persist in the long-term, although the majority of studies assessed gait pattern especially in the first months after TKA.

RESEARCH QUESTION

What are the long-term gait impairments in patients after TKA compared to healthy age-matched subjects?

METHODS

A systematic search was conducted on MEDLINE/PubMed, EMBASE, CENTRAL and Scopus databases. Observational studies or randomized controlled trials investigating gait spatial-temporal, kinematic and kinetics parameters in a time-window longer than 6 months in patients with TKA compared to healthy age-matched subjects were included. Methodological quality was assessed using the modified Downs and Black (D&B) checklist and participants' characteristics, surgical procedures details and outcome measures were extracted. Pooled or un-pooled findings were categorized into "6 months - 1 year" and "more than 1 year" timepoint categories.

RESULTS

Twenty-eight studies (976 patients) were included. Overall quality was fair with a mean modified D&B score of 63.5 %. Reduced speed, stride length, cadence and longer stance phase were found in patients when compared to healthy individuals at "6 months - 1 year" follow-up. Spatial-temporal parameters deficits were also found at more than 1 year after TKA, where lower single-limb support and longer double-limb support durations were detected. These impairments occurred in concomitance with decreased knee range of motion along the sagittal and frontal planes and altered kinetic parameters. Hip kinematic and kinetic long-term impairments were also detected after TKA.

SIGNIFICANCE

These findings highlighted long-term gait pattern alterations in patients with TKA compared to age-matched healthy subjects. Future studies should identify interventions able to reduce long-term gait pattern alterations and improve function in patients after TKA.

Sensory integration and segmental control of posture during pregnancy

BACKGROUND

Approximately 25% of pregnant people fall, yet the underlying mechanisms of this increased fall-risk remain unclear. Prior studies examining pregnancy and balance have utilized center of pressure analyses and reported mixed results. The purpose of this study was to examine sensory and segmental contributions to postural control throughout pregnancy using accelerometer-based measures of sway.

METHODS

Thirty pregnant people (first trimester: n = 10, second trimester: n = 10, third trimester: n = 10) and 10 healthy, nonpregnant control people stood quietly for one minute in four conditions: eyes open on a firm surface, eyes closed on a firm surface, eyes open on a foam pad, and eyes closed on foam. Postural sway was quantified using the root mean square accelerations in the anterior-posterior and medial-lateral directions from an inertial sensor at the lumbar region. Sensory sway ratios, segmental coherence and co-phase, were calculated to assess sensory contributions and segmental control, respectively.

FINDINGS

Pregnant people did not display greater sway compared to healthy, nonpregnant controls. There were no group differences in vestibular, visual, or somatosensory sway ratios, and no significant differences in balance control strategies between pregnant and nonpregnant participants across sensory conditions.

INTERPRETATION

The small effects observed here contrast prior studies and suggest larger, definitive studies are needed to assess the effect of pregnancy on postural control. This study serves as a preliminary exploration of pregnant sensory and segmental postural control and highlights the need for future to hone the role of balance in fall risk during pregnancy.

Clinical and exercise professional opinion of return-to-running readiness after childbirth: an international Delphi study and consensus statement

Female athletes have identified a lack of guidance as a barrier to successfully returning to running postpartum, and existing guidelines are vague. Our aim was to define the current practice of determining postpartum run-readiness through a consensus survey of international clinicians and exercise professionals in postpartum exercise to assist clinicians and inform sport policy changes.A three-round Delphi approach was used to gain international consensus from clinicians and exercise professionals on run-readiness postpartum. Professionals who work with postpartum runners participated in an online survey to answer open-ended questions about the following postpartum return-to-running topics: definitions (runner and postpartum), key biopsychosocial milestones that runners need to meet, recommended screening, timeline to initiate running, support items, education topics and factors that contribute to advising against running. Consensus was defined as ≥75% participant agreement.One hundred and eighteen professionals participated in round I, 107 participated in round II (response rate 90.6%) and 95 participated in round III (response rate 80.5%). Responses indicated that, following a minimum 3-week period of rest and recovery, an individualised timeline and gradual return to running progression can be considered. Screening for medical and psychological concerns, current physical capacity, and prior training history is recommended prior to a return to running.This study proposes recommendations for the initial guidance on return-to-running postpartum, framed in the context of current research and consensus from professionals. Future research is needed to strengthen and validate specific recommendations and develop guidelines for best practice when returning-to-running after childbirth.