Ninety-day complication rate based on 532 Latarjet procedures in Dutch hospitals with different operation volumes.

BACKGROUND: In this study, we aimed to provide insight into the 90-day complication rates following the Latarjet procedure. Data from 2015 were collected from multiple hospitals in the Netherlands, with different volumes of Latarjet procedures. Our second aim was to examine which patient and surgical factors were associated with complications. METHODS: We conducted a retrospective chart review of 13 hospitals between 2015 and 2022. Data regarding complications within 90 days of Latarjet procedures were extracted. The effect of sex, age, body mass index (BMI), smoking, previous shoulder operations, fixation material, hospital volume, screw size, and operation time on the complication rate was assessed by multivariable logistic regression analysis. RESULTS: Of the 532 included patients, 58 (10.9%) had complications. The most common complications were material failure (n = 19, 3.6%) and nerve injury (n = 13, 2.4%). The risk of complications was lower for male patients than for female patients (odds ratio, 0.40; 95% confidence interval, 0.21-0.77; P = .006). Age, BMI, smoking, previous shoulder operations, type of fixation material, hospital volume, screw size, and operation time were not associated with complications. CONCLUSION: The 90-day complication rate after the Latarjet procedure was 10.9% and was higher in female patients than in male patients. Age, BMI, smoking, previous shoulder operations, type of fixation material, hospital volume, screw size, and operation time did not affect complication rates. We advise setting up a national registry to prevent under-reporting of complications.

Early migration in unicompartmental knee arthroplasty: a radiostereometric study of 26 patients with 24 months of follow-up.

BACKGROUND AND PURPOSE: Aseptic loosening, mainly caused by migration, is one of the most common indications for revisions in unicompartmental knee arthroplasty (UKA). In this study, we investigated the early migration of the Persona Partial Knee (PPK, Zimmer Biomet, Warsaw, IN), a cemented medial fixed-bearing unicompartmental knee prosthesis, and evaluated the clinical results. PATIENTS AND METHODS: 26 primary PPKs were implanted. Radiographs were obtained direct postoperatively, at 6 weeks, 6, 12 and 24 months postoperatively. Migration of the femoral and tibial component was calculated using model-based radiostereophotogrammetric analysis (mRSA) in terms of translations and rotations. Patient-reported outcome measures (PROMs) were also registered. RESULTS: At 24 months postoperatively, we found low migration of both the femoral and tibial component in the first 6 months, after which both components stabilized. Only the rotation of the tibial component about the z-axis did not stabilize. All PROMs improved after 24 months compared with preoperative PROMs. CONCLUSION: The Persona Partial Knee shows low migration of both the femoral and tibial component and PROMs were improved at 24 months follow-up. Long-term follow-up is needed to investigate the performance of the prosthesis compared with other prostheses.

No effect of fixation type on early and late mortality after total knee arthroplasty: a Dutch arthroplasty register study.

PURPOSE: Postoperative mortality is commonly reported as outcome measurement after total knee arthroplasty (TKA). Mortality might be influenced by multiple factors including cementation of the prosthesis. Until now, the influence of cementation on early and late mortality after TKA is unknown. The aim of the present study was to determine the effect of fixation on early and late mortality after primary TKA. METHODS: All patients in the Dutch Arthroplasty Register (LROI) with a primary TKA for osteoarthritis were eligible for inclusion. Data collected from 2007 to 2014 with follow-up until January 2020 were used. Survival analysis was performed by using Kaplan-Meier and Cox survival analysis to determine the mortality rate according to fixation. Adjustments were made for age at time of surgery, gender, American Society of Anaesthesiologists class, and year of surgery. RESULTS: In total 108,687 TKA were included for analysis, which comprised 95,857 cemented, 6,140 cementless and 6,690 hybrid TKA. The early and late mortality rate in cemented TKA was statistically not different compared to cementless or hybrid TKA at 30 days, 31-90 days, 91 days-1 year and 1-5 years. The hazard ratio at 30 days was 1.05 (CI 0.49-2.25) for hybrid fixation, and 1.46 (CI 0.74-2.90) for cementless fixation compared to cemented fixation. The 1-5 years hazard ratio was 1.06 (CI 0.96-1.17) and 0.97 (CI 0.87-1.08), respectively. CONCLUSION: Based on register data, method of fixation does not influence early mortality after primary TKA. This suggests that there is no preferred fixation technique for primary TKA based on the mortality rates. LEVEL OF EVIDENCE: IV.

Comparable mid-term revision rates of primary cemented and cementless total knee arthroplasties in 201,211 cases in the Dutch Arthroplasty Register (2007-2017).

PURPOSE: Long-term failure of total knee arthroplasty (TKA) is mostly due to loosening of the prosthesis. In this study, the short- and mid-term revision rates of cemented vs cementless TKAs were investigated. Comparable short- and mid-term survival rates of both fixation methods were expected. METHODS: Data on all cemented and cementless TKAs performed between 2007 and 2017 were retrieved from the Dutch Arthroplasty Register. The cumulative crude incidence of revision of cemented and cementless TKA was calculated. Death was considered a competing risk. Revision rates were compared using multivariable Cox proportional hazard regression analysis. The associations between fixation method and type of revision or reason for revision were tested using logistic regression analyses. RESULTS: In total, 190,651 (94.8%) cemented and 10,560 (5.3%) cementless TKAs were evaluated. Both groups had comparable case characteristics. Cemented TKAs were inserted more often in cases with previous knee surgery compared to cementless TKAs (32% vs 27%). The cumulative incidence of revision after 9 years was 5.5% (CI 5.3-5.6%) for cemented and 5.8% (CI 5.2-6.4%) for cementless TKAs (p = 0.2). Cementless TKAs were more often revised due to loosening of the tibial (27% vs 18%; p < 0.001) or the femoral component (7% vs 5%; p = 0.005) than cemented TKAs. Cemented TKAs were more often revised due to infection (17% vs 9%; p = 0.004) than cementless TKAs. CONCLUSION: In conclusion, cemented and cementless TKAs have comparable short- and mid-term revision rates based on a nationwide register study. LEVEL OF EVIDENCE: III.

Treatment of metatarsalgia based on claw toe deformity through soft tissue release of the metatarsophalangeal joint and resection of the proximal interphalangeal joint: Evaluation based on foot kinematics and plantar pressure distribution.

INTRODUCTION: This study investigated the effect of operative claw toe correction with release of the metatarsophalangeal (MTP) joint, repositioning of the plantar fat pad and resection of the proximal interphalangeal joint on foot kinematics, plantar pressure distribution and Foot Function Index (FFI). METHODS: Prospective experimental study with pretest-posttest design. The plantar pressure, 3D foot kinematics and the FFI of 15 patients with symptomatic claw toes were measured three months before and 12months after surgery. Mean pressure, peak pressure and pressure time integral per sensor and various foot angles were calculated for the pre- and posttest and compared to a control group (N=15). RESULTS: Claw toe patients have increased pressure under the distal part of the metatarsal head and less pressure under the proximal part of the metatarsal heads compared to healthy controls. After surgery, there was a redistribution of pressure, resulting in a significant decrease of pressure under the distal part and an increase under the proximal part of the metatarsal head, providing a more equal plantar pressure distribution. Except for some small areas under the forefoot, heel and toes, there were no significant differences in pressure distribution between the operated feet and controls. Small, but significant differences between the pre- and postoperative condition were found for the lateral arch angle, calcaneus/malleolus supination and tibio-talar flexion. The score on the FFI improved statistically significant. DISCUSSION: These findings imply that the present operative procedure results in a more equal distribution of the plantar pressure under the forefoot and decrease of pain and offers successful treatment of metatarsalgia based on claw toe deformity.

Diminished Dynamic Physical Performance Is Associated With Orthostatic Hypotension in Geriatric Outpatients.

BACKGROUND AND PURPOSE: Orthostatic hypotension (OH), a blood pressure drop after postural change, is a highly prevalent and disabling syndrome in older adults. Yet, the association between physical performance and OH is not clearly established. The aim of this study was to determine whether different types of physical performance are associated with OH in a clinically relevant population of geriatric outpatients. METHODS: This cross-sectional study included 280 geriatric outpatients (mean age: 82.2 years, standard deviation: 7.1). Orthostatic hypotension was determined using intermittently measured blood pressure and continuously measured blood pressure in a random subgroup of 58 patients. Physical performance was classified into a dynamic type (4-m Walk Test, Chair Stand Test, and Timed Up and Go test) and a static type (standing balance tests, handgrip strength). Associations were analyzed using logistic regression models with adjustments for age, sex, weight, and height. RESULTS: Diminished physical performance on the Chair Stand Test was associated with OH measured intermittently. Diminished physical performance on all dynamic physical domains (4-m Walk Test, Chair Stand Test, and Timed Up and Go test) was associated with OH measured continuously. Static physical performance was not significantly associated with OH. CONCLUSION: Dynamic physical performance tests with a substantial postural change and center of mass displacement were significantly associated with OH. The influence of physical performance on OH in daily routine activities should be further explored to establish counteracting interventions.

The Reliance on Vestibular Information During Standing Balance Control Decreases With Severity of Vestibular Dysfunction.

The vestibular system is involved in gaze stabilization and standing balance control. However, it is unclear whether vestibular dysfunction affects both processes to a similar extent. Therefore, the objective of this study was to determine how the reliance on vestibular information during standing balance control is related to gaze stabilization deficits in patients with vestibular dysfunction. Eleven patients with vestibular dysfunction and twelve healthy subjects were included. Gaze stabilization deficits were established by spontaneous nystagmus examination, caloric test, rotational chair test, and head impulse test. Standing balance control was assessed by measuring the body sway (BS) responses to continuous support surface rotations of 0.5° and 1.0° peak-to-peak while subjects had their eyes closed. A balance control model was fitted on the measured BS responses to estimate balance control parameters, including the vestibular weight, which represents the reliance on vestibular information. Using multivariate analysis of variance, balance parameters were compared between patients with vestibular dysfunction and healthy subjects. Robust regression was used to investigate correlations between gaze stabilization and the vestibular weight. Our results showed that the vestibular weight was smaller in patients with vestibular dysfunction than in healthy subjects (F = 7.67, p = 0.011). The vestibular weight during 0.5° peak-to-peak support surface rotations decreased with increasing spontaneous nystagmus eye velocity (ρ = -0.82, p < 0.001). In addition, the vestibular weight during 0.5° and 1.0° peak-to-peak support surface rotations decreased with increasing ocular response bias during rotational chair testing (ρ = -0.72, p = 0.02 and ρ = -0.67, p = 0.04, respectively). These findings suggest that the reliance on vestibular information during standing balance control decreases with the severity of vestibular dysfunction. We conclude that particular gaze stabilization tests may be used to predict the effect of vestibular dysfunction on standing balance control.

Evidence in Support of the Independent Channel Model Describing the Sensorimotor Control of Human Stance Using a Humanoid Robot.

The Independent Channel (IC) model is a commonly used linear balance control model in the frequency domain to analyze human balance control using system identification and parameter estimation. The IC model is a rudimentary and noise-free description of balance behavior in the frequency domain, where a stable model representation is not guaranteed. In this study, we conducted firstly time-domain simulations with added noise, and secondly robot experiments by implementing the IC model in a real-world robot (PostuRob II) to test the validity and stability of the model in the time domain and for real world situations. Balance behavior of seven healthy participants was measured during upright stance by applying pseudorandom continuous support surface rotations. System identification and parameter estimation were used to describe the balance behavior with the IC model in the frequency domain. The IC model with the estimated parameters from human experiments was implemented in Simulink for computer simulations including noise in the time domain and robot experiments using the humanoid robot PostuRob II. Again, system identification and parameter estimation were used to describe the simulated balance behavior. Time series, Frequency Response Functions, and estimated parameters from human experiments, computer simulations, and robot experiments were compared with each other. The computer simulations showed similar balance behavior and estimated control parameters compared to the human experiments, in the time and frequency domain. Also, the IC model was able to control the humanoid robot by keeping it upright, but showed small differences compared to the human experiments in the time and frequency domain, especially at high frequencies. We conclude that the IC model, a descriptive model in the frequency domain, can imitate human balance behavior also in the time domain, both in computer simulations with added noise and real world situations with a humanoid robot. This provides further evidence that the IC model is a valid description of human balance control.

Blood pressure change does not associate with Center of Pressure movement after postural transition in geriatric outpatients.

BACKGROUND: Orthostatic hypotension (OH), a blood pressure drop after postural change, is associated with impaired standing balance and falls in older adults. This study aimed to assess the association between blood pressure (BP) and a measure of quality of standing balance, i.e. Center of Pressure (CoP) movement, after postural change from supine to standing position in geriatric outpatients, and to compare CoP movement between patients with and without OH. METHODS: In a random subgroup of 75 consecutive patients who were referred to a geriatric outpatient clinic, intermittent BP measurements were obtained simultaneously with CoP measurements in mediolateral and anterior-posterior direction directly after postural change during 3 min of quiet stance with eyes open on a force plate. Additional measurements of continuous BP were available in n = 38 patients. Associations between BP change during postural change and CoP movement were analyzed using Spearman correlation. Mann-Whitney-U tests were used to compare CoP movement between patients with OH and without OH, in which OH was defined as a BP drop exceeding 20 mmHg of systolic BP (SBP) and/or 10 mmHg of diastolic BP (DBP) within 3 min after postural change. RESULTS: OH measured intermittently was found in 8 out of 75 (11%) and OH measured continuously in 22 out of 38 patients (57.9%). BP change did not associate with CoP movement. CoP movement did not differ significantly between patients with and without OH. CONCLUSIONS: Results do not underpin the added value of CoP movement measurements in diagnosing OH in a clinical setting. Neither could we identify the role of CoP measurements in the understanding of the relation between OH and impaired standing balance.

A Sensitivity Analysis of an Inverted Pendulum Balance Control Model.

Balance control models are used to describe balance behavior in health and disease. We identified the unique contribution and relative importance of each parameter of a commonly used balance control model, the Independent Channel (IC) model, to identify which parameters are crucial to describe balance behavior. The balance behavior was expressed by transfer functions (TFs), representing the relationship between sensory perturbations and body sway as a function of frequency, in terms of amplitude (i.e., magnitude) and timing (i.e., phase). The model included an inverted pendulum controlled by a neuromuscular system, described by several parameters. Local sensitivity of each parameter was determined for both the magnitude and phase using partial derivatives. Both the intrinsic stiffness and proportional gain shape the magnitude at low frequencies (0.1-1 Hz). The derivative gain shapes the peak and slope of the magnitude between 0.5 and 0.9 Hz. The sensory weight influences the overall magnitude, and does not have any effect on the phase. The effect of the time delay becomes apparent in the phase above 0.6 Hz. The force feedback parameters and intrinsic stiffness have a small effect compared with the other parameters. All parameters shape the TF magnitude and phase and therefore play a role in the balance behavior. The sensory weight, time delay, derivative gain, and the proportional gain have a unique effect on the TFs, while the force feedback parameters and intrinsic stiffness contribute less. More insight in the unique contribution and relative importance of all parameters shows which parameters are crucial and critical to identify underlying differences in balance behavior between different patient groups.

Standing Up Slowly Antagonises Initial Blood Pressure Decrease in Older Adults with Orthostatic Hypotension.

BACKGROUND: Orthostatic hypotension (OH) is common in older adults and associated with increased morbidity and mortality, loss of independence and high health-care costs. Standing up slowly is a recommended non-pharmacological intervention. However, the effectiveness of this advice has not been well studied. OBJECTIVES: The aim of this study was to investigate whether standing up slowly antagonises posture-related blood pressure (BP) decrease in a clinically relevant population of geriatric outpatients. METHODS: In this cross-sectional study, 24 community-dwelling older adults referred to a geriatric outpatient clinic and diagnosed with OH were included. BP was measured continuously during 3 consecutive transitions from supine to standing position during normal, slow and fast transition. RESULTS: The relative BP decrease at 0-15 s after slow transition was significantly lower than after normal transition (p = 0.003 for both systolic BP and diastolic BP) and fast transition (p = 0.045 for systolic BP; diastolic BP: non-significant). The relative diastolic BP decrease at 60-180 s after normal transition was significantly lower than after fast transition (p = 0.029). CONCLUSION: Standing up slowly antagonises BP decrease predominantly during the first 15 s of standing up in a clinically relevant population of geriatric outpatients diagnosed with OH. Results support the non-pharmacological intervention in clinical practice to counteract OH.

Reliability of System Identification Techniques to Assess Standing Balance in Healthy Elderly.

OBJECTIVES: System identification techniques have the potential to assess the contribution of the underlying systems involved in standing balance by applying well-known disturbances. We investigated the reliability of standing balance parameters obtained with multivariate closed loop system identification techniques. METHODS: In twelve healthy elderly balance tests were performed twice a day during three days. Body sway was measured during two minutes of standing with eyes closed and the Balance test Room (BalRoom) was used to apply four disturbances simultaneously: two sensory disturbances, to the proprioceptive and the visual system, and two mechanical disturbances applied at the leg and trunk segment. Using system identification techniques, sensitivity functions of the sensory disturbances and the neuromuscular controller were estimated. Based on the generalizability theory (G theory), systematic errors and sources of variability were assessed using linear mixed models and reliability was assessed by computing indexes of dependability (ID), standard error of measurement (SEM) and minimal detectable change (MDC). RESULTS: A systematic error was found between the first and second trial in the sensitivity functions. No systematic error was found in the neuromuscular controller and body sway. The reliability of 15 of 25 parameters and body sway were moderate to excellent when the results of two trials on three days were averaged. To reach an excellent reliability on one day in 7 out of 25 parameters, it was predicted that at least seven trials must be averaged. CONCLUSION: This study shows that system identification techniques are a promising method to assess the underlying systems involved in standing balance in elderly. However, most of the parameters do not appear to be reliable unless a large number of trials are collected across multiple days. To reach an excellent reliability in one third of the parameters, a training session for participants is needed and at least seven trials of two minutes must be performed on one day.

Low cognitive status is associated with a lower ability to maintain standing balance in elderly outpatients.

BACKGROUND: Evidence is emerging that cognitive performance is involved in maintaining balance and thereby involved in falls in the elderly. OBJECTIVE: To investigate the association of cognitive status with measures of standing balance in elderly outpatients. METHODS: In a cross-sectional study, 197 community-dwelling elderly [mean age (SD) 81.9 (7.1) years] referred to a geriatric outpatient clinic were included and subsequently dichotomized into a group with low and normal cognitive status based on cut-off values of the Mini-Mental State Examination, Montreal Cognitive Assessment and Visual Association Test. The ability to maintain standing balance as well as the center of pressure (CoP) movement were assessed during 10 s of side-by-side, semi-tandem and tandem stance with eyes open and eyes closed. Logistic and linear regression were used to examine the association between cognitive status and measures of standing balance adjusted for age, gender and highest completed education. RESULTS: Low cognitive status in elderly outpatients was associated with a lower ability to maintain 10 s of balance in side-by-side stance with eyes closed [OR (95% CI): 3.57 (1.60; 7.97)] and in semi-tandem stance with eyes open and eyes closed [OR (95% CI): 3.93 (1.71; 9.00) and OR (95% CI): 2.32 (1.11; 4.82), respectively]. Cognitive status was not associated with CoP movement. CONCLUSION: Low cognitive status associates with a lower ability to maintain standing balance in more demanding standing conditions in elderly outpatients. This may have implications for routine geriatric screening strategies and interpretation of results of either standing balance or cognitive tests.

Walking speed in elderly outpatients depends on the assessment method.

Walking speed is shown to be an important indicator of the health status and function in older adults and part of the comprehensive geriatric assessment in clinical practice. The present study aimed to assess the influence of different assessment methods on walking speed and its association with the key aspects of poor health status, i.e., the presence of low cognitive performance and cardiopulmonary disease. In 288 community-dwelling elderly (mean age 82.2 ± 7.1 years) referred to a geriatric outpatient clinic, walking speed was assessed with the 4-m, 10-m, and 6-min walking tests. The mean walking speed assessed with the 10-m walking test was higher compared to the 4-m and 6-min walking tests (mean difference (95% CI) 0.11 m/s (0.10; 0.13) and 0.08 m/s (0.04; 0.13), respectively). No significant difference was found in the walking speed assessed with the 4-m compared to the 6-min walking test (mean difference (95% CI) -0.03 m/s (-0.08; 0.03)). ICCs showed excellent agreement of the 4-m with the 10-m walking test and fair to good agreement of the 6-min with the 4-m as well as 10-m walking test. The presence of low cognitive performance was negatively associated with walking speed, with the highest effect size for the 4-m walking test. The presence of cardiopulmonary disease was negatively associated with walking speed as well, with the highest effect size for the 6-min walking test. In conclusion, in the clinically relevant population of elderly outpatients, walking speed and its interpretation depends on the assessment method, which therefore cannot be used interchangeably in clinical practice.

Blood pressure associates with standing balance in elderly outpatients.

OBJECTIVES: Assessment of the association of blood pressure measurements in supine and standing position after a postural change, as a proxy for blood pressure regulation, with standing balance in a clinically relevant cohort of elderly, is of special interest as blood pressure may be important to identify patients at risk of having impaired standing balance in routine geriatric assessment. MATERIALS AND METHODS: In a cross-sectional cohort study, 197 community-dwelling elderly referred to a geriatric outpatient clinic of a middle-sized teaching hospital were included. Blood pressure was measured intermittently (n = 197) and continuously (subsample, n = 58) before and after a controlled postural change from supine to standing position. The ability to maintain standing balance was assessed during ten seconds of side-by-side, semi-tandem and tandem stance, with both eyes open and eyes closed. Self-reported impaired standing balance and history of falls were recorded by questionnaires. Logistic regression analyses were used to examine the association between blood pressure and 1) the ability to maintain standing balance; 2) self-reported impaired standing balance; and 3) history of falls, adjusted for age and sex. RESULTS: Blood pressure decrease after postural change, measured continuously, was associated with reduced ability to maintain standing balance in semi-tandem stance with eyes closed and with increased self-reported impaired standing balance and falls. Presence of orthostatic hypotension was associated with reduced ability to maintain standing balance in semi-tandem stance with eyes closed for both intermittent and continuous measurements and with increased self-reported impaired standing balance for continuous measurements. CONCLUSION: Continuous blood pressure measurements are of additional value to identify patients at risk of having impaired standing balance and may therefore be useful in routine geriatric care.

Age-related differences in quality of standing balance using a composite score.

BACKGROUND: Age-related differences in standing balance are not detected by testing the ability to maintain balance. Quality of standing balance might be more sensitive to detect age-related differences. OBJECTIVE: To study age-related differences in quality of standing balance, center of pressure (CoP) movement was evaluated using a wide range of CoP parameters in several standing conditions in healthy young and old participants. METHODS: In 35 healthy young (18-30 years) and 75 healthy old (70-80 years) participants, CoP movement was assessed in eight standing conditions on a force plate, including side-by-side, one-leg, semi-tandem and tandem stance, both with eyes open and eyes closed. Direction-specific CoP composite scores were calculated from standardized single CoP parameters (mean amplitude, amplitude variability, mean velocity, velocity variability and range) in anterior-posterior (AP) and medial-lateral (ML) direction. Linear regression analysis was used to detect age-related differences in single CoP parameters and composite scores - adjusted for gender, height and weight. RESULTS: Overall, single CoP parameters were higher in old compared to young participants, but no single CoP parameter consistently demonstrated the largest effect size for all standing conditions. Age-related differences were demonstrated for CoP composite scores in AP direction (tandem eyes open; semi-tandem eyes closed; p < 0.001). CoP composite scores in ML direction were consistently higher for all standing conditions in old compared to young participants (p < 0.001). CONCLUSION: CoP composite scores in ML direction were the most consistent parameters to detect age-related differences in quality of standing balance in healthy participants and might be of clinical value to detect subtle changes in quality of standing balance.

Impaired standing balance in elderly: a new engineering method helps to unravel causes and effects.

Deteriorated balance control is the most frequent cause of falls and injuries in the elderly. Balance control comprises a complex interplay of several underlying systems (ie, the sensory systems, the motor system, and the nervous system). Available clinical balance tests determine the patient's ability to maintain standing balance under defined test conditions and aim to describe the current state of this ability. However, these tests do not reveal which of the underlying systems is deteriorated and to what extent, so that the relation between cause and effect often remains unclear. Especially detection of early-stage balance control deterioration is difficult, because the balance control system is redundant and elderly may use compensation strategies. This article describes a new method that is able to identify causal relationships in deteriorated balance control, called CLSIT (Closed Loop System Identification Technique). Identification of impaired balance with CLSIT is a base for development of tailored interventions and compensation strategies to reduce the often serious consequences of deteriorated balance control in the elderly.

Muscle strength rather than muscle mass is associated with standing balance in elderly outpatients.

OBJECTIVES: Assessment of the association of muscle characteristics with standing balance is of special interest, as muscles are a target for potential intervention (ie, by strength training). DESIGN: Cross-sectional study. SETTING: Geriatric outpatient clinic. PARTICIPANTS: The study included 197 community-dwelling elderly outpatients (78 men, 119 women; mean age 82 years). MEASUREMENTS: Muscle characteristics included handgrip and knee extension strength, appendicular lean mass divided by height squared (ALM/height(2)), and lean mass as percentage of body mass. Two aspects of standing balance were assessed: the ability to maintain balance, and the quality of balance measured by Center of Pressure (CoP) movement during 10 seconds of side-by-side, semitandem, and tandem stance, with both eyes open and eyes closed. Logistic and linear regression models were adjusted for age, and additionally for height, body mass, cognitive function, and multimorbidity. RESULTS: Handgrip and knee extension strength, adjusted for age, were positively related to the ability to maintain balance with eyes open in side-by-side (P = .011; P = .043), semitandem (P = .005; P = .021), and tandem stance (P = .012; P = .014), and with eyes closed in side-by-side (P = .004; P = .004) and semitandem stance (not significant; P = .046). Additional adjustments affected the results only slightly. ALM/height(2) and lean mass percentage were not associated with the ability to maintain standing balance, except for an association between ALM/height(2) and tandem stance with eyes open (P = .033) that disappeared after additional adjustments. Muscle characteristics were not associated with CoP movement. CONCLUSION: Muscle strength rather than muscle mass was positively associated with the ability to maintain standing balance in elderly outpatients. Assessment of CoP movement was not of additional value.