Hip and Knee Proprioception in Elite, Amateur, and Novice Tennis Players

The effect of compression and combined compression-tactile stimulation on lower limb somatosensory acuity

Background

Lower limb somatosensation and proprioception are important for maintaining balance. Research has shown that compression garments or exposure to textured surfaces, can enhance somatosensation however, little is known about the effect of combined compression and texture on somatosensory acuity in the lower limb. This study aimed to assess the effects of combined compression socks with a plantar textured sole, on lower limb somatosensory acuity.

Methods

Thirty participants completed a somatosensory acuity task (active movement extent discrimination apparatus; AMEDA) under three conditions: barefoot (control condition), standard knee-high compression sock (compression sock), and knee-high compression sock with internal rubber nodules situated on the sole (textured-compression sock). Somatosensory acuity was assessed between the different sock conditions for the (i) entire group, (ii) high performers, and (iii) low performers. It was hypothesized that low performers would see gains wearing either sock, but the greatest improvement would be in the textured-compression sock condition.

Results

AMEDA scores were not significantly different between conditions when the entire group was analyzed (p = 0.078). The low performers showed an improvement in somatosensory acuity when wearing the compression sock (p = 0.037) and the textured compression sock (p = 0.024), when compared to barefoot, but there was no difference between the two sock conditions (p > 0.05). The high performers did not show any improvement (p > 0.05 for all).

Conclusion

These findings demonstrate that additional sensory feedback may be beneficial to individuals with lower baseline somatosensory acuity but is unlikely to provide benefit for those with higher somatosensory acuity.

Postural Balance in Young Tennis Players of Varied Competition Levels

The aim of this study was to investigate the effect of young tennis players' expertise on their postural balance (PB) under sensorial conditions with eyes open (EO) and with eyes closed (EC). Our participants were 75 healthy adolescents aged 15-18 years, divided into three groups based on their skill levels: (a) national tennis players (NAT; n = 25), regional tennis players (REG; n =25), and a control group of non-sport practitioners (CG; n = 25). We recorded center of pressure area and mean velocity on a force platform while participants stood in bipedal and unipedal stances in EO and EC conditions for all three groups. Statistical analyses showed that NAT participants swayed less than CG participants in all conditions and less than REG participants in the bipedal stance with EC and in the unipedal stance, both with EO and EC. Thus, tennis practice/experience may have improved PB in this sample, as high-level tennis players had better PB compared to novices, especially in challenging conditions.

Proprioceptive sensitivity to imposed finger deflections

Hand proprioception, the sense of the posture and movements of the wrist and digits, is critical to dexterous manual behavior and to stereognosis, the ability to sense the three-dimensional structure of objects held in the hand. To better understand this sensory modality and its role in hand function, we sought to characterize the acuity with which the postures and movements of finger joints are sensed. To this end, we measured the ability of human subjects to discriminate changes in posture and speed around the three joints of the index finger. In these experiments, we isolated the sensory component by imposing the postures on an otherwise still hand, to complement other studies in which subjects made judgments on actively achieved postures. We found that subjects could reliably sense 12-16% changes in joint angle and 18-32% changes in joint speed. Furthermore, the acuity for posture and speed was comparable across the three joints of the finger. Finally, task performance was unaffected by the presence of a vibratory stimulus, calling into question the role of cutaneous cues in hand proprioception.NEW & NOTEWORTHY Manual dexterity and stereognosis are supported by two exquisite sensory systems, namely touch and proprioception. Here, we measure the sensitivity of hand proprioception and show that humans can sense the posture and movements of the fingers with great accuracy. We also show that application of a skin vibration does not impair sensitivity, suggesting that proprioceptive acuity relies primarily on receptors in the muscles (and possibly tendons) rather than the skin.

Reliability of hip joint position sense tests using a clinically applicable measurement tool in elderly participants with unilateral hip osteoarthritis

Hip joint proprioception is vital in maintaining posture and stability in elderly individuals. Examining hip joint position sense (JPS) using reliable tools is important in contemporary clinical practice. The objective of this study is to evaluate the intra-rater and inter-rater reliability of hip JPS tests using a clinically applicable measurement tool in elderly individuals with unilateral hip osteoarthritis (OA). Sixty-two individuals (mean age = 67.5 years) diagnosed with unilateral hip OA participated in this study. The JPS tests were evaluated using a digital inclinometer in hip flexion and abduction directions. The absolute difference between target and reproduced angle (repositioning error) in degrees was taken to measure JPS accuracy. The intraclass correlation coefficient (ICC (2.k), was used to assess the reliability. The Intra rater-reliability for hip JPS tests showed very good agreement in the lying position (hip flexion-ICC = 0.88–0.92; standard error of measurement (SEM) = 0.06–0.07, hip abduction-ICC = 0.89–0.91; SEM = 0.06–0.07) and good agreement in the standing position (hip flexion-ICC = 0.69–0.72; SEM = 0.07, hip abduction-ICC = 0.66–0.69; SEM = 0.06–0.08). Likewise, inter-rater reliability for hip JPS tests demonstrated very good agreement in the lying position (hip flexion-ICC = 0.87–0.89; SEM = 0.06–0.07, hip abduction-ICC = 0.87–0.91; SEM = 0.07) and good agreement in the standing position (hip flexion-ICC = 0.64–0.66; SEM = 0.08, hip abduction-ICC = 0.60–0.72; SEM = 0.06–0.09). The results support the use of hip JPS tests in clinical practice and should be incorporated in assessing and managing elderly participants with hip OA.

Lower limb joint position sense and prospective hamstring injury

BACKGROUND

The hamstrings remain the most injured muscle group within the Australian Football League (AFL).

OBJECTIVE

To investigate preseason measures of hip and knee joint position sense (JPS) and prospective hamstring injury in AFL players.

DESIGN

Prospective cohort study.

METHODS

A total of 116 AFL players were recruited for this study. JPS was assessed with 3-D sensors using mono-articular hip (45° flexion and 0°) and knee (90° and 45° flexion) joint reproduction tests conducted in the preseason. Hamstring injury data were collected prospectively in the following AFL season. Wilcoxon-signed rank tests were used to assess between the subsequently injured and uninjured limbs. Mann-Whitney U tests were used to assess between group differences and odds ratio (OR) were used to predict players at risk of hamstring injury.

RESULTS

Eight players with JPS data sustained a season hamstring injury and 108 players did not. JPS was not significantly different between the subsequently injured and uninjured limbs (all P values > 0.05). No significant differences for any JPS measure were found between the subsequently injured and uninjured players (all p's > 0.05). ORs did not achieve significance for AE (2.7, p = 0.21) or for RMSE (OR = 1.9, p = 0.44).

CONCLUSION

Lower limb JPS measures were not predictive of hamstring injury in AFL players.

Balance dynamics are related to age and levels of expertise. Application in young and adult tennis players

In tennis, coaches consider balance fundamental for the acquisition of skilled motor performance. However, the potential relationship between balance and tennis expertise and performance has not been explored yet. Therefore, this study assessed the relationship between balance and tennis performance using linear and non-linear parameters through 1) the comparison of tennis players of different ages and levels of expertise, and 2) analyzing the relationship between balance and tennis serving speed and accuracy. One hundred and six recreational and expert male tennis players took part in the study (age range 10-35 years old). Temporal dynamics of postural control during a balance task on an unstable surface were analyzed through the mean velocity and the detrended fluctuation analysis (DFAV) of center of pressure (COP). Tennis serve performance was quantified by measuring accuracy and speed. Traditional variables measuring balance performance only showed differences according to age but not to sport performance. COP showed a reduction of auto-correlated variability (reflected by DFAV) with age but mainly in expert players. COP dynamics was the only balance parameter discriminating sport expertise and it was related to age. Balance dynamics exhibited by expert tennis players DFAV results support the idea that, along the years, sport experience induces balance adaptations characterized by a higher ability to perform postural adjustments. These results also reinforce the use of non-linear analysis to reveal subtle balance adaptations produced by sport practice. Finally, the lack of correlations suggests that balance, measured with scattering variables, in a non-specific task is not a main determinant of sport performance in tennis serve.

Effects of functional movement screen training in high-school baseball players: A randomized controlled clinical trial

BACKGROUND

In recent years, the functional movement screen (FMS) and FMS training have attracted attention as a means of preventing injury, but no studies have examined the effect of such training in high-school baseball players. The aim of this study was to clarify the effect of FMS training on FMS score, physical function and baseball performance in high-school baseball players.

METHODS

Subjects in this randomized controlled clinical trial were high-school male baseball players assigned to either an FMS training group (intervention group) or a control group. The intervention group performed FMS training 4 times per week for 12 weeks. FMS ability, physical function, and baseball performance were measured prior to the intervention, 8, 12, and 24 weeks after the intervention in the subjects' school environment.

RESULTS

A total of 71 baseball players aged 15 to 17 years were recruited and assigned to either an intervention group (n = 37) or control group (n = 34). There was no significant difference in the characteristics of participants between the 2 groups. Most FMS scores improved to 12 weeks after continued training. In the intervention group compared with the control group, deep squat, hurdle step, inline lunge, active straight leg raise, trunk stability push-up and rotary stability FMS score, total FMS score and eyes closed single leg stance time significantly increased after 8 weeks of training. While hurdle step, inline lunge, active straight leg raise, trunk stability push-up, total FMS score, and eyes closed single leg stance time significantly increased, pitching ball speed significantly decreased at the end of the 12 week training period. Eyes closed single leg stance time and feeling of fatigue significantly improved 12 weeks after training. The number of subjects who scored less than 14 for the total FMS score in the intervention group compared with control group were significantly less after 8 and 12 weeks of FMS training.

CONCLUSION

FMS training for 8 weeks contributes to improving FMS scores for high-school baseball players, but FMS scores go down if FMS training is not continued.

TRIAL REGISTRATION

University Hospital Medical Information Network Center, Tokyo, Japan: UMIN000027553. Registered on May 30, 2017.

Low Rate of Return to Preinjury Tegner Activity Level Among Recreational Athletes: Results at 1 Year After Primary ACL Reconstruction

Background

There is limited information about the functional recovery and rate of return to preinjury levels of sports among recreational athletes after anterior cruciate ligament reconstruction (ACLR).

Purpose

To investigate the recovery of quadriceps or hamstring strength, assess functional performance, and determine the rate of return to preinjury sports levels among recreational athletes at 1 year after ACLR.

Study Design

Cohort study; Level of evidence, 3.

Methods

A total of 91 recreational-level athletes who underwent anatomic single-bundle ACLR were enrolled. We evaluated the limb symmetry index (LSI) of the quadriceps and hamstring peak torque strength at 60°, in addition to hop test performance (single-leg, triple, crossover, and 6-m timed), patient-reported outcomes, and pre- versus postoperative Tegner activity levels. Outcomes were compared between younger (age <25 years) and older patients (age ≥25 years).

Results

There were 48 patients in the younger group and 43 patients in the older group. At 1-year follow-up, the overall LSIs for quadriceps strength and hamstring strength were 77% and 86%, respectively, and the LSIs of the hop tests were 79% for single-leg, 81% for triple, 84% for crossover, and 85% for 6-m timed hop. Overall, only 24% patients returned to their preinjury Tegner level, and only 8% of patients met the criteria for return to pivoting, cutting, and jumping sports. At 1-year follow-up, the younger group showed significantly more quadriceps strength than the older group (85% vs 64%; P = .0001), better single, triple, crossover, and 6-m timed hop test results (85% vs 69%, P = .003; 84% vs 75%, P = .046; 91% vs. 74%, P < .001; and 91% vs 76%, P = .003, respectively), higher Lysholm score (87 vs 74; P < 0.001) and International Knee Document Committee score (82 vs 66; P < .001), and a higher rate of return to preinjury Tegner level (35% vs 12%; P = .009).

Conclusion

Only 24% of patients returned to the preinjury Tegner level at 1 year after ACLR (35% younger group vs 12% older group; P = .009). This information might be helpful in setting realistic expectations for recreational athletes after surgery.

Upper limb proprioception and fine motor function in young pianists

BACKGROUND

This study investigated if intensive piano training may be associated with improved motor and somatosensory function. We systematically examined upper limb proprioception, which is known to play an essential role in skill movements, and motor function in young pianists.

METHOD

Forty-four typically developing children who either regularly played piano for more than six years (N = 16) or had no experience playing musical instruments (N = 28) participated. Elbow and wrist joint proprioceptive acuity was assessed using a manipulandum. The wrist/elbow was passively flexed to a target with participants actively trying to match the just experienced target position. Motor function was assessed using the Movement Assessment Battery for Children (MABC-2).

RESULTS

First, children in the pianist group exhibited significantly lower position sense bias (systematic error) at both the elbow and wrist when compared to controls. Position sense precision (random error) was not different between groups. Second, the piano group exhibited enhanced fine motor function as shown by higher manual dexterity MABC-2 scores. Performance in other motor domains (aiming and catching or balance) was not improved in young pianists. Third, a lower position sense bias was correlated with a higher level of manual dexterity.

CONCLUSION

This study documents that children who regularly play the piano have superior upper limb position sense acuity. Specifically, smaller position sense bias, i.e., less systematic error. Superior upper position sense acuity in young pianists is associated with higher fine motor functions.

Inter-task transfer of prism adaptation depends on exposed task mastery

The sensorimotor system sets up plastic alterations to face new demands. Terms such as adaptation and learning are broadly used to describe a variety of processes underlying this aptitude. The mechanisms whereby transformations acquired to face a perturbation generalize to other situations or stay context-dependent remain weakly understood. Here, we compared the performance of hand pointing vs throwing to visual targets while facing an optical shift of the visual field (prismatic deviation). We found that the transfer of compensations was conditioned by the task performed during exposure to the perturbation: compensations transferred from pointing to throwing but not at all from throwing to pointing. Additionally, expertise on the task performed during exposure had a marked influence on the amount of transfer to the non-exposed task: throwing experts (dart players) remarkably transferred compensations to the pointing task. Our results reveal that different processes underlying these distinct transfer properties may be at work to face a given perturbation. Their solicitation depends on mastery for the exposed task, which is responsible for different patterns of inter-task transfer. An important implication is that transfer properties, and not only after-effects, should be included as a criterion for adaptation. At the theoretical level, we suggest that tasks may need to be mastered before they can be subjected to adaptation, which has new implications for the distinction between learning and adaptation.

DIFFERENCES IN KNEE SENSORIMOTOR CONTROL BY PHYSICAL ACTIVITY LEVEL AND SEX

Objective:

The aim of this study was to compare the differences in knee sensorimotor control between healthy men and women by measuring the joint position sense (JPS), sensation of muscle tension (steadiness), and onset of muscle activation (OMA).

Methods:

Twenty-four healthy women and 27 healthy men were tested. Knee sensorimotor control was assessed using the JPS test with electrogoniometers in 3 different ranges of motion, sensation of muscle tension using the isometric steadiness technique, and OMA against a mechanical perturbation. Each assessment was compared by sex, physical activity level, and right or left lower limb.

Results:

The men obtained better values in the JPS test between 90º and 60º and between 30º and 0º than the women. The subjects with higher levels of physical activity also showed better values, between 90º and 60º and between 30º and 0º. The best results for steadiness were found in the women and the subjects with higher levels of physical activity. In the OMA test, no significant differences were found in the studied variables.

Conclusion:

The results suggest that higher levels of physical activity may determine better sensorimotor control. Men have better articular sensation, and women have better muscle strength control. Level of evidence III, Cross sectional study.

Heritability of proprioceptive senses

Heritability studies using the twin model have provided the basis to disentangle genetic and environmental factors that contribute to several complex human traits. However, the relative importance of these factors to individual differences in proprioception is largely unknown despite the fact that proprioceptive senses are of great importance, allowing us to respond to stimuli stemming from the space around us and react to altering circumstances. Hence, a total of 44 healthy male twins (11 MZ and 11 DZ pairs), 19-28 yr old, were examined for movement, position, and force sense at the elbow joint, and their heritability estimates were computed. Results showed that genetic factors explained 1) 72 and 76% of the total variance of movement sense at the start and the end of the movement, respectively, 2) 60 to 77% of the total variance of position sense, depending on the angle of elbow flexion and whether forearm positioning was active or passive, and 3) 73 and 70% of the total variance of the force sense at 90 and 60° of elbow flexion, respectively. It is concluded that proprioception assessed by these conscious sensations is to a substantial degree genetically dependent, with heritability indexes ranging from 0.60 to 0.77, depending on the task. NEW & NOTEWORTHY Proprioceptive acuity varies among people, but it is not known how much of this variability is due to differences in their genes. This study is the first to report that proprioception, expressed as movement sense, position sense, and force sense, is substantially heritable, and it is conceivable that this may have implications for motor learning and control, neural development, and neurorehabilitation.

Eighty-three per cent of elite athletes return to preinjury sport after anterior cruciate ligament reconstruction: a systematic review with meta-analysis of return to sport rates, graft rupture rates and performance outcomes

Objectives

The primary objective was to calculate the rate of return to sport (RTS) following anterior cruciate ligament (ACL) reconstruction in elite athletes. Secondary objectives were to estimate the time taken to RTS, calculate rates of ACL graft rupture, evaluate postsurgical athletic performance and identify determinants of RTS.

Design

Pooled RTS and graft rupture rates were calculated using random effects proportion meta-analysis. Time to RTS, performance data and determinants of RTS were synthesised descriptively.

Data sources

MEDLINE, EMBASE, AMED, CINAHL, AMI, PEDro, SPORTDiscus and The Cochrane Library were searched from inception to 19 January 2016. Hand searching of 10 sports medicine journals and reference checking were also performed.

Eligibility criteria for selecting studies

Studies were included if they reported the ratio of elite athletes who returned to their preinjury level of sport following ACL reconstruction. Twenty-four studies were included.

Results

The pooled RTS rate was 83% (95% CI 77% to 88%). The mean time to RTS ranged from 6 to 13 months. The pooled graft rupture rate was 5.2% (95% CI 2.8% to 8.3%). Six out of nine studies that included a noninjured control group found no significant deterioration in athletic performance following ACL reconstruction. Indicators of greater athletic skill or value to the team were associated with RTS.

Summary and conclusions

Eighty-three per cent of elite athletes returned to sport following ACL reconstruction, while 5.2% sustained a graft rupture. Most athletes who returned to sport performed comparably with matched, uninjured controls. This information may assist in guiding expectations of athletes and clinicians following ACL reconstruction.

Assessing proprioception: A critical review of methods

To control movement, the brain has to integrate proprioceptive information from a variety of mechanoreceptors. The role of proprioception in daily activities, exercise, and sports has been extensively investigated, using different techniques, yet the proprioceptive mechanisms underlying human movement control are still unclear. In the current work we have reviewed understanding of proprioception and the three testing methods: threshold to detection of passive motion, joint position reproduction, and active movement extent discrimination, all of which have been used for assessing proprioception. The origin of the methods, the different testing apparatus, and the procedures and protocols used in each approach are compared and discussed. Recommendations are made for choosing an appropriate technique when assessing proprioceptive mechanisms in different contexts.

Reproducibility of a knee and hip proprioception test in healthy older adults

BACKGROUND

Proprioception can be assessed by measuring joint position sense (JPS). Most studies have focused on JPS of the knee joint while literature for other joints especially for hip JPS is scarce. Although some studies have evaluated proprioception of the knee joint, the reproducibility of methods has rarely been investigated.

AIMS

To estimate intrasession reliability and agreement of an active-active JPS test for hip flexion/abduction and knee flexion in healthy older adults.

METHODS

Nineteen healthy older adults participated in this study. The proprioception of the hip (flexion and abduction) and knee (flexion) were assessed in both legs using the "active-active" reproduction technique. Intraclass correlation coefficient (ICC), standard error of measurement (SEM), and limits of agreement (LOA) were estimated for relative angular error (RE), absolute angular error (AE), and variable angular error (VE).

RESULTS

Reliability of our JPS test was substantial to almost perfect for the RE for both joints and legs (ICC values ranging from 0.75 to 0.93). We also found that the ICC values for AE were substantial for knee flexion and hip abduction of the left and right leg. The ICC results of VE showed poor reliability for hip and knee joints. SEM and LOA values for hip abduction were generally lower than for hip and knee flexion, indicating lower measurement error or more precise scores for the proprioception test of hip abduction.

CONCLUSION(S)

Proprioceptive acuity of the knee and hip joints in healthy older adults can be reliably assessed with an active-active procedure in a standing position with respect to relative and absolute error.

Assessing Proprioception: A Systematic Review of Possibilities

Proprioception is a vital aspect of motor control and when degraded or lost can have a profound impact on function in diverse clinical populations. This systematic review aimed to identify clinically related tools to measure proprioceptive acuity, to classify the construct(s) underpinning the tools, and to report on the clinimetric properties of the tools. We searched key databases with the pertinent search terms, and from an initial list of 935 articles, we identified 57 of relevance. These articles described 32 different tools or methods to quantify proprioception. There was wide variation in methods, the joints able to be tested, and the populations sampled. The predominant construct was active or passive joint position detection, followed by passive motion detection and motion direction discrimination. The clinimetric properties were mostly poorly evaluated or reported. The Rivermead Assessment of Somatosensory Perception was generally considered to be a valid and reliable tool but with low precision; other tools with higher precision are potentially not clinically feasible. Clinicians and clinical researchers can use the summary tables to make more informed decisions about which tool to use to match their predominant requirements. Further discussion and research is needed to produce measures of proprioception that have improved validity and utility.

Level of competitive success achieved by elite athletes and multi-joint proprioceptive ability

OBJECTIVES

Proprioceptive ability has been suggested to underpin elite sports performance. Accordingly, this study examined the relationship between an athlete's proprioceptive ability, competition level achieved, and years of sport-specific training.

DESIGN

Cross-sectional study.

METHODS

One hundred elite athletes, at competition levels ranging from regional to international, in aerobic gymnastics, swimming, sports dancing, badminton and soccer, were assessed for proprioceptive acuity at the ankle, knee, spine, shoulder, and finger joints. An active movement extent discrimination test was conducted at each joint, to measure ability to discriminate small differences in movements made to physical stops.

RESULTS

Multiple regression analysis showed that 30% of the variance in the sport competition level an athlete achieved could be accounted for by an equation that included: ankle movement discrimination score, years of sport-specific training, and shoulder and spinal movement discrimination scores (p<0.001). Mean proprioceptive acuity score over these three predictor joints was significantly correlated with sport competition level achieved (r=0.48, p<0.001), highlighting the importance of proprioceptive ability in underpinning elite sports performance. Years of sport-specific training correlated with an athlete's sport competition level achieved (r=0.29, p=0.004), however, proprioceptive acuity was not correlated with years of sport-specific training, whether averaged over joints or considered singly for each joint tested (all r≤0.13, p≥0.217).

CONCLUSIONS

Proprioceptive acuity is significantly associated with the performance level achieved by sports elites. The amount of improvement in proprioceptive acuity associated with sport-specific training may be constrained by biologically determined factors.

Effect of anterior cruciate ligament injury and reconstruction on proprioceptive acuity of knee rotation in the transverse plane

BACKGROUND

Studies assessing proprioceptive acuity in anterior cruciate ligament (ACL)-deficient knees have only considered proprioception for knee movements in the sagittal plane rather than in the transverse plane (ie, rotation), despite the fact that the ACL plays a critical role in knee rotational stability and that the ACL is injured almost exclusively with a rotation mechanism. Therefore a test of proprioception is needed that involves movements similar to the mechanism of injury, in this case, rotation.

PURPOSE

To determine whether proprioceptive acuity in rotation changes after ACL injury and reconstruction, and to examine differences in proprioceptive acuity, range, laxity, and activity level among injured knees, contralateral knees, and healthy controls.

DESIGN

Cohort study; Level of evidence, 2.

METHODS

Proprioceptive acuity for active knee rotation movements, passive rotation range of motion, anterior knee laxity, and knee function were measured in 20 consecutive participants with unilateral ACL rupture and 20 matched controls. Reconstruction was performed using a single-incision technique with a 4-strand hamstring tendon autograft. Thirty participants (15 control and 15 ACL reconstructed) were retested at 3 months, and 14 with ACL reconstruction were tested at 6 months.

RESULTS

A deficit was found in preoperative knee rotation proprioception compared with healthy controls (P = .031). Three months after reconstruction, there was a significant improvement (P = .049) in proprioceptive acuity, single-plane anterior laxity (P = .01), and self-reported knee function (P = .001). At 3 months after reconstruction, proprioceptive acuity of the ACL-reconstructed knee was correlated with reported activity level (r = .63; P = .021).

CONCLUSION

Knee rotation proprioception is reduced in ACL-deficient participants compared with healthy controls. Three to 6 months after reconstruction, rotation proprioceptive acuity, laxity, and function were improved. While these findings are consistent with a return to previous activity level 6 months after reconstruction, the extent of graft maturation and restoration of kinematics should also inform the decision about return to sport.

The effects of sensorimotor training on knee proprioception and function for patients with knee osteoarthritis: a preliminary report

Objective: To investigate the effects of a sensorimotor training programme in osteoarthritic patients.

Design: Randomized, single-blind, controlled trial.

Setting: Kinesiology laboratory at School of Physical Therapy.

Participants: A total of 60 patients were randomly assigned to the training group and the control group. Only 29 patients (training group, 15; control group, 14) completed the study.

Intervention: The training group underwent a sensorimotor training programme using a sling suspension system complemented by a routine physical therapy. The control group underwent a routine physical therapy.

Main measures: Active joint repositioning, functional testings, and self-reported function with the Western Ontario & McMaster Universities Arthritis Index before and after the eight-week intervention.

Results: There were significant differences between the two groups with respect to the improvement in proprioception as measured by active joint repositioning (the changes in the absolute error were 1.9± 1.7°, training group versus 0.1 ± 2.8°, control group (P<0.05), and in self-reported functional difficulty (33.2 ±35.1, training group versus 8.0± 10.2, control group; P<0.05)). There was no significant difference between the two groups in other outcomes.

Conclusion: A sensorimotor training using a sling suspension system improved the patients' proprioception in the knee joints and their self-reported function. Thus, these exercises may serve as an exercise programme for patients with knee osteoarthritis.

Relationship between hip strength and frontal plane posture of the knee during a forward lunge

OBJECTIVE

Excessive frontal plane knee movement during forward lunge movements might be associated with the occurrence of knee injuries in tennis. Here, we attempt to determine whether hip muscle strength is related to the frontal plane motion of the knee during a functional lunge movement.

DESIGN

A correlational study.

PARTICIPANTS

A total of 84 healthy subjects (76 men, 8 women), with no history of knee or lower leg complaints.

INTERVENTIONS

Muscle strength of six hip muscle groups was measured using a handheld dynamometer. Subjects were videotaped during a forward lunge and peak knee valgus or varus angles were determined using a digital video analysis software program.

MAIN OUTCOME MEASUREMENTS

A correlation was examined between hip muscle strength and the amount of frontal plane movement of the knee during a forward lunge.

RESULTS

There were no significant differences in hip muscle strength between the valgus group and the varus group during the forward lunge movement. No significant correlation was found between the strength of the assessed hip muscles and the amount of movement into valgus/varus. In the varus group a moderate positive correlation was found between the External Rotation/Internal Rotation force ratio and the amount of knee varus during the forward lunge movement (r = 0.31, p = 0.03).

CONCLUSIONS

The findings suggest that in healthy subjects hip muscle strength is not correlated to the amount of valgus/varus movement of the knee during a forward lunge. This suggests that other factors (eg, proprioception, core hip stability) might be more important in controlling knee movement during this tennis-specific movement.

Sensory-specific balance training in older adults: effect on position, movement, and velocity sense at the ankle

BACKGROUND AND PURPOSE

Age-related changes in proprioception contribute to impairments in postural control and increased fall risk in older adults. The purpose of this randomized controlled trial was to examine the effects of balance exercises on proprioception.

SUBJECTS

The participants were 36 older people and 24 younger people who were healthy.

METHODS

Older participants were randomly assigned to a balance exercise group (n=17) or a falls prevention education group (n=19). Baseline, postintervention, and 8-week follow-up measurements of 3 proprioceptive measures (threshold to perception of passive movement, passive joint position sense, and velocity discrimination) were obtained at the ankle. For comparative purposes, younger participants underwent a one-time assessment of the 3 proprioceptive measures.

RESULTS

Postintervention improvements in velocity discrimination were found in the balance exercise group when compared with values at baseline and in the falls prevention education group. Age-related differences found at baseline were reduced in the balance exercise group after intervention. Improvements were not maintained at the 8-week follow-up. Threshold to perception of passive movement and passive joint position sense did not change as a function of the exercise intervention.

DISCUSSION AND CONCLUSION

The results suggest that short-term improvements in velocity sense, but not movement and position sense, may be achieved following a balance exercise intervention.