Effect of a neoprene sleeve on knee joint kinesthesis: influence of different testing procedures

Influence of compression garments on proprioception: A systematic review and meta-analysis

Compression garments (CGs) are commonly used in rehabilitation and sports contexts to enhance performance and speed up recovery. Despite the growing use of CGs in recent decades, there is no unanimous consensus on their overall influence on joint proprioception. In this current meta-analysis, we aim to fill this knowledge gap by assessing the impact of CGs on joint proprioception. We conducted a literature search across seven databases and one registry. Ultimately, we included 27 studies with 671 participants. The meta-analysis revealed that wearing CGs resulted in a significant reduction in absolute error during joint position sensing (Hedges' g: -0.64, p = 0.006) as compared to no CGs. However, further analyses of variables such as constant error (p = 0.308), variable error (p = 0.541) during joint position sense tests, threshold to detect passive motion (p = 0.757), and active movement extent discrimination (p = 0.842) did not show a significant impact of CGs. The review also identified gaps in the reporting of certain outcomes, such as parameters of CGs, reporting of performance, individual-reported outcomes, and lack of placebo comparators. Consequently, this review provides guidelines for future studies that may facilitate evidence-based synthesis and ultimately contribute to a better understanding of the overall influence of CGs on joint proprioception.

Effects of Using a Shoulder/Scapular Brace on the Posture and Muscle Activity of Healthy University Students during Prolonged Typing-A Randomized Controlled Cross-Over Trial

Laptop use appears to contribute to poor working postures and neck pain among university students. Postural braces have the potential to improve upper back/neck posture and therefore might have a role as an ergonomic aid for this population. Therefore, the purpose of this study was to assess the short-term effects of scapular bracing on pain, fatigue, cervicothoracic posture, and the activity of the neck and upper-back muscles in healthy college students. A randomized controlled crossover trial was conducted to evaluate the self-reported pain and fatigue, the amplitude and median frequency of surface electromyography in neck extensors, upper trapezius, and lower trapezius, as well as the neck and shoulder sagittal alignment (measured by inertial sensors and digital photographs) during a 30-min typing task in a sample of young, healthy university students with or without a scapular brace. The brace condition resulted in significantly smaller levels of bilateral trapezius muscle activity (p < 0.01). Rounded shoulder posture was slightly better in the brace condition, but these differences were not significant (p > 0.05). There were no significant immediate differences in pain or fatigue scores, neck alignment, or the electromyographic activity of the other muscles tested between brace and non-brace conditions (all p > 0.05). However, bracing appears to immediately reduce the electromyographic activity of the lower trapezius muscles (p < 0.05). These findings shed some light on the possible advantages of scapular bracing for enhancing laptop ergonomics in this group of individuals. Future studies are warranted to evaluate the effects of different types of braces, the importance of matching the brace to the user, and the short- and long-term effects of brace use on computer posture and muscle activity.

Alternatives to Knee Braces

Knee braces continue to be a widely utilized piece of medical equipment, ranging from simple over the counter sleeves to more complex functional braces, with the ability to provide electrical stimulation to muscle groups. Despite their popularity, alternatives to knee braces exist for patients who find braces to be ineffective, uncomfortable, cumbersome, or overly expensive. While high-quality studies are lacking for modalities such as neoprene sleeves, compression stockings, and kinesiotaping, there is promising evidence that these interventions can confer an element of stability and pain relief for a variety of knee pathologies both with regard to acute and chronic injuries as well as in the postoperative rehabilitation period. While no "holy grail" exists for the ideal brace, or bracing alternative, it is important for providers to be aware of the options available to patients as well as the current evidence for these various modalities, so that the provider can best guide musculoskeletal care.

Hip and Knee Bracing: Categorization, Treatment Algorithm, and Systematic Review

Hip and knee braces or orthoses are often used to provide support after surgery and to prevent or reduce the severity of injuries. The braces are used for stabilization, immobilization, mechanical correction, and rehabilitation. Hip braces consist of stabilization and unloader variations, whereas knee braces are composed of knee sleeves and patellofemoral, prophylactic, unloader, and functional braces. Indications vary widely and depend on the type of brace. Hip braces can treat osteoarthritis to instability after total hip arthroplasty. Knee brace indications range from mild arthralgias to instability and osteoarthritis. Although braces are routinely used clinically, high-level evidence is sparse for their use. With this review, the different types and uses of hip and knee braces have been defined, and their indications exemplified in hopes of spurring future research.

Is patellofemoral pain preventable? A systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

To evaluate the effectiveness of interventions to reduce the risk of incident patellofemoral pain.

DESIGN

Systematic review and meta-analysis, with strength of evidence evaluated separately for each intervention type.

DATA SOURCES

MEDLINE, EMBASE, CINAHL, Web of Science and SPORTDiscus.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomised controlled trials evaluating the effectiveness of interventions to reduce patellofemoral pain risk compared with a control/non-exposed group.

RESULTS

Thirteen trials of mostly military recruits and young athletes analysed six different interventions. There was low certainty evidence from two trials (227 participants) that patellofemoral braces worn during physical activity (compared with no brace) effectively reduced the risk of patellofemoral pain (risk ratio (RR) 0.40, 95% CI 0.22 to 0.73; I2=24.0%). There was low certainty evidence from one trial (320 participants) that running technique retraining to (run softer) reduced patellofemoral pain risk (RR 0.21, 95% CI 0.07 to 0.60). There was low certainty evidence from four trials (3364 participants) that multicomponent (strengthening/neuromuscular) exercise programmes did not significantly reduce the risk of patellofemoral pain (RR 0.49, 95% CI 0.18 to 1.36; I2=64.9%), although broad CIs may reflect exercise dose variations among studies. There was very low certainty evidence from four trials (2314 participants) that foot orthoses (compared with flat inserts/no orthosis) did not significantly reduce the risk of patellofemoral pain (RR 0.63, 95% CI 0.35 to 1.13; I2=0.0%). Static stretching and a running programme that progressed intensity (compared with volume) did not significantly influence patellofemoral pain risk (single studies).

CONCLUSION

There is low-level evidence that patellofemoral braces and running technique retraining can reduce the risk of patellofemoral pain by 60%-79%.

Position of compression garment around the knee affects healthy adults' knee joint position sense acuity

Athletes use compression garments (CGs) to improve sport performance, accelerate rehabilitation from knee injuries or to enhance joint position sense (JPS). The position of CGs around the knee may affect knee JPS but the data is inconsistent. The purpose of the present study was to determine the effects of CG position on healthy adults' knee joint position sense acuity. In a counterbalanced, single-blinded study, 16 healthy young adults (8 female, age: 25.5 y) performed an active knee joint position-matching task with and without (CON) a below-knee (BK), above-knee (AK), or whole-knee (WK) CG in a randomized order on the dominant (CompDom) or the non-dominant leg (CompNon-Dom). We also determined the magnitude of tissue compression by measuring anatomical thigh and calf cross sectional area (CSA) in standing using magnetic resonance imaging (MRI). Subjects had less absolute repositioning error (magnitude of error) in BK compared with CON condition. On the other hand, the analysis of the direction of error (constant error) revealed that in each condition subjects tended to underestimate the target position (AK, BK and CON: 75%; WK: 94%). In WK condition there was a significantly larger negative error (-2.7 ± 3.4) as compared with CON (-1.6 ± 3.7) condition. There also was less variable error, in WK compared to BK and CON conditions, indicating less variability in their position sense using a WK CG, regardless of the underestimation. CG reduced thigh CSA by 4.5 cm² or 3% and calf CSA by Δ1.3 cm² or 1%. The position of CG relative to the knee modifies knee JPS. The findings helps us better understand how the application of a WK CG may support athletic activities.

Effects of knee orthoses on kinesthetic awareness and balance in healthy individuals

Introduction

Conflicting evidence exists regarding the effects of knee orthoses on proprioception. One belief is that pressure applied by orthoses heightens kinesthetic awareness and that this affects balance. This study aimed to investigate the effects of two different orthosis designs on kinesthetic awareness and balance in healthy individuals.

Methods

Twenty individuals (13 women) participated in this case series study. Each was tested wearing 1/no orthosis, 2/soft elastic orthosis and 3/non-elastic jointed orthosis. Pressure under orthoses was recorded. Kinesthetic awareness was investigated by testing joint position sense and threshold to detection of passive motion. Balance was tested using a modified sensory organization test.

Results

Non-elastic jointed orthoses applied the greatest pressure to the knee. With non-elastic jointed orthoses, threshold to detection of passive motion was significantly poorer for pooled results (p = 0.02) and when the start position of the knee was 70° (mean threshold = 0.6°, 0.6°, 0.7° for no-orthosis, elastic and jointed-orthoses; p = 0.03). No major differences were observed in JPS or balance and correlation between proprioception and balance was poor.

Conclusions

There may be a limit to the amount of pressure that should be applied to the knee joint by an orthosis. Exceeding this limit may compromise kinesthetic awareness.

An above-knee compression garment does not improve passive knee joint position sense in healthy adults

We determined the effects of wearing an above-knee compression garment (CG) on knee joint position sense. Healthy young adults (n = 24, age = 27.46 ± 4.65 years) performed a passive knee position-matching task on an isokinetic dynamometer with each leg separately. We determined the magnitude of compression by measuring anatomical thigh cross sectional area (CSA) in standing using magnetic resonance imaging. Wearing the CG compressed CSA by 2% (t = 2.91, p = 0.010, Cohen’s d = 0.68). Repeated measures ANOVA (rANOVA) with three repetition factors (condition: CG, no CG; leg: right dominant, left non-dominant; and target angles: 30°, 45°, 60°) revealed an effect of angles (p < 0.001), where the matching of knee joint position was more accurate at 60° compared to 30° and 45° (p < 0.001). However, CG did not reduce passive joint position sense errors. In fact, joint position error was less without CG (p = 0.014). In conclusion, while CG does compress the thigh it does not afford the purported benefits for proprioception as measured by a target-matching task in the present study.

Metatarsal strapping tightness effect to vertical jump performance

The study investigated the effect of metatarsal strapping on vertical jump performance and evaluated the difference in lower limb kinematics and electromyographic signal (EMG) between different strapping force levels. Twelve male callisthenic athletes completed single vertical jump from a squat posture with hands on hips under three conditions as non-strapping (NS), moderate strapping (MS) and high strapping (HS) round metatarsals. Ground reaction force (GRF) was recorded with KISTLER force platform to calculate the vertical jump height. Angles of ankle, knee and hip were measured with VICON motion analysis system and EMG data were recorded with mega6000 system. Data showed that jump height was significantly higher under HS than NS condition. Compared with NS, ankle inversion decreased significantly during take-off and external rotation increased significantly during landing with MS. Significant difference was also found in the muscle activity of tibialis anterior between non-strapping and strapping conditions.

The effect of knee brace and knee sleeve on the proprioception of the knee in young non-professional healthy sportsmen

BACKGROUND

Proprioception has been defined as the capacity to feel the position of a joint in space as sensed by the central nervous system. Prophylactic knee braces are supposed to help in knee injury prevention not just with a mechanical support of the joint but also improving proprioception. The main aim of this study was to determine the effects of a knee brace and a knee sleeve on knee proprioception. The secondary aim was to determine if different starting angles of the knee and different movement directions influence knee proprioception.

METHODS

We tested a group of twenty healthy male sport students without knee injuries. They were tested with the brace, with the sleeve and without support. The threshold of detection of passive knee movement with a starting knee angle of 30° and 60°, both in flexion and extension was determined.

RESULTS

We did not find any statistically significant change in the threshold of detection of passive knee movement wearing the brace or the sleeve compared to the unsupported condition (p=0.462, α=0.05). We found a significantly lower proprioceptive sensitivity starting at the more flexed knee angle (p=0.005, α=0.05) and moving in extension than in the other test situations (p=0.001, α=0.05).

CONCLUSION

Movement direction and starting position appear to influence the threshold of detection of passive knee movement. The results of this study also suggest that knee supports do not influence either positively or negatively knee proprioception of uninjured active subjects.

Mechanisms and risk factors for noncontact ACL injury in age mature athletes who engage in field or court sports: a summary of the literature since 1980

Epidemiological data show that in the last 10 years alone the incidence and rate of anterior cruciate ligament (ACL) injuries have not changed appreciably. Furthermore, many ACL injuries appear to be noncontact in nature and sustained while engaging in some field or court sport. Thus, the need to investigate novel methods and adopt training strategies to prevent ACL injuries is paramount. To do so, however, requires an understanding of the mechanisms and risk factors for the injury. The aim of this review was to investigate the mechanisms and risk factors for noncontact ACL injuries in age mature athletes who compete in field or court sports. A search of the entire MEDLINE database for biomedicine was performed, and an iterative reference check was also conducted. A total of 87 articles disclosed met the eligibility criteria. Articles were grouped into 'themes'; 'anatomical and biomechanical mechanisms and risk factors,' 'intrinsic mechanisms and risk factors,' and 'extrinsic mechanisms and risk factors.' In this review, it is concluded that there are still a number of risk factors and mechanisms for noncontact ACL injury that are not well understood. However, the importance of dynamic knee joint stability is highlighted. It is also suggested that novel methods for preventing ACL injury be investigated and developed.

Scapular bracing and alteration of posture and muscle activity in overhead athletes with poor posture

CONTEXT

Overhead athletes commonly have poor posture. Commercial braces are used to improve posture and function, but few researchers have examined the effects of shoulder or scapular bracing on posture and scapular muscle activity.

OBJECTIVE

To examine whether a scapular stabilization brace acutely alters posture and scapular muscle activity in healthy overhead athletes with forward-head, rounded-shoulder posture (FHRSP).

DESIGN

Randomized controlled clinical trial.

SETTING

Applied biomechanics laboratory.

PATIENTS OR OTHER PARTICIPANTS

Thirty-eight healthy overhead athletes with FHRSP.

INTERVENTION(S)

Participants were assigned randomly to 2 groups: compression shirt with no strap tension (S) and compression shirt with the straps fully tensioned (S + T). Posture was measured using lateral-view photography with retroreflective markers. Electromyography (EMG) of the upper trapezius (UT), middle trapezius (MT), lower trapezius (LT), and serratus anterior (SA) in the dominant upper extremity was measured during 4 exercises (scapular punches, W's, Y's, T's) and 2 glenohumeral motions (forward flexion, shoulder extension). Posture and exercise EMG measurements were taken with and without the brace applied.

MAIN OUTCOME MEASURE(S)

Head and shoulder angles were measured from lateral-view digital photographs. Normalized surface EMG was used to assess mean muscle activation of the UT, MT, LT, and SA.

RESULTS

Application of the brace decreased forward shoulder angle in the S + T condition. Brace application also caused a small increase in LT EMG during forward flexion and Y's and a small decrease in UT and MT EMG during shoulder extension. Brace application in the S + T group decreased UT EMG during W's, whereas UT EMG increased during W's in the S group.

CONCLUSIONS

Application of the scapular brace improved shoulder posture and scapular muscle activity, but EMG changes were highly variable. Use of a scapular brace might improve shoulder posture and muscle activity in overhead athletes with poor posture.

A kinetic and kinematic analysis of the effect of stochastic resonance electrical stimulation and knee sleeve during gait in osteoarthritis of the knee

Extended use of knee sleeves in populations at risk for knee osteoarthritis progression has shown functional and quality of life benefits; however, additional comprehensive kinematic and kinetic analyses are needed to determine possible physical mechanisms of these benefits which may be due to the sleeve's ability to enhance knee proprioception. A novel means of extending these enhancements may be through stochastic resonance stimulation. Our goal was to determine whether the use of a knee sleeve alone or combined with stochastic resonance electrical stimulation improves knee mechanics in knee osteoarthritis. Gait kinetics and kinematics were assessed in subjects with medial knee osteoarthritis when presented with four conditions: control1, no electrical stimulation/sleeve, 75% threshold stimulation/sleeve, and control2. An increase in knee flexion angle throughout stance and a decrease in flexion moment occurring immediately after initial contact were seen in the stimulation/sleeve and sleeve alone conditions; however, these treatment conditions did not affect the knee adduction angle and internal knee abduction moment during weight acceptance. No differences were found between the sleeve alone and the stochastic resonance with sleeve conditions. A knee sleeve can improve sagittal-plane knee kinematics and kinetics, although adding the current configuration of stochastic resonance did not enhance these effects.

Static and dynamic postural control in competitive athletes after anterior cruciate ligament reconstruction and controls

PURPOSE

To evaluate the test-retest reliability and compare the static and dynamic postural control values in competitive athletes following anterior cruciate ligament (ACL) reconstruction and controls.

METHODS

Thirty athletes, 8.4 ± 1.8 months after ACL reconstruction, and thirty healthy matched controls were asked to execute single-leg stance and single-legged drop jump tests onto a force plate. Amplitude and velocity in anteroposterior and mediolateral directions, and mean total velocity were measured for static evaluation. Peak vertical ground reaction force (PVGRF) during landing and takeoff and loading rate were measured for dynamic evaluation. To evaluate test-retest reliability, 15 participants of each group repeated the tests 6-8 days after the first session. Mixed model of analysis of variance was used to determine differences between the involved, uninvolved, and control limbs. The test-retest reliability was measured using intraclass correlation coefficient and standard error of measurement.

RESULTS

Greater postural sway has been observed in the operated leg of ACL-reconstructed athletes compared with the non-operated side (P < 0.01) and the matched limb of the control group (P < 0.01). During landing, PVGRF and loading rate on the uninvolved limb of the athletes who had undergone ACL reconstruction were greater in comparison with those of the control group (P < 0.001). Both static and dynamic postural measures have high test-retest reliability, ranging from 0.73 to 0.88.

CONCLUSIONS

Static and dynamic postural measures are reliable tests to evaluate functional performance of athletes following ACL reconstruction. Eight months postsurgery, competitive athletes still demonstrated postural asymmetries, compared to matched controls, which might result in their susceptibility to future ACL injury.

LEVEL OF EVIDENCE

Prognostic study, case-control, Level III.

Stochastic resonance electrical stimulation to improve proprioception in knee osteoarthritis

Proprioceptive deficits occur with knee osteoarthritis (OA) and improving proprioception may slow joint degeneration by allowing more appropriate joint loading. Stochastic resonance (SR) stimulation improves balance and the sensitivity of specific mechanoreceptors. Our purpose was to evaluate the effects of SR electrical stimulation combined with a knee sleeve on proprioception in subjects with knee OA. Joint position sense (JPS) was measured in 38 subjects with knee OA during four conditions in both a partial weight-bearing (PWB) and non weight-bearing (NWB) task: no electrical stimulation/no sleeve, no electrical stimulation/sleeve, 50 μA-RMS stimulation/sleeve, and 75 μA-RMS stimulation/sleeve. Subjects also reported their knee pain, stiffness, functionality (WOMAC), and instability. Repeated measures ANOVA and Spearman correlations were performed to investigate differences between the conditions and relationships among the outcome measures. JPS during the 75 μA-RMS stimulation/sleeve and sleeve alone conditions was significantly improved compared to the control condition in the PWB task. However, the 75 μA-RMS stimulation/sleeve and the sleeve alone conditions did not differ from each other. A moderate correlation was found between the improvements with the 75 μA-RMS stimulation/sleeve condition compared to the JPS of the control condition in the PWB task. No differences in JPS were found between the four conditions in the NWB task. Significant correlations were found between the control JPS and WOMAC indices (p<0.005). Improved proprioception during the PWB task was achieved with a sleeve alone and in combination with SR stimulation. The observed correlations suggest that subjects with larger proprioceptive deficits may benefit most from these therapies.

Influence of magnetic knee wraps on joint proprioception in individuals with osteoarthritis: a randomized controlled pilot trial

Objective: To determine the effects of magnetic knee wraps (MKWs) on joint position sense (JPS) in individuals with mild-to-moderate knee osteoarthritis.

Design: Randomized, double-blind, placebo-controlled pilot trial.

Setting: Rehabilitation clinic of a tertiary hospital.

Subjects: Fifty volunteers with mild-to-moderate knee osteoarthritis participated and 33 (66%) completed the trial; only one (2%) withdrew due to study-related adverse effects.

Interventions: Knee wraps with a static magnetic field (35 mT) were compared with control knee wraps for 12 weeks.

Main measures: The main outcome measure was JPS at first, fourth, and twelfth week while applying of the knee wrap, quantified as the ability to replicate target knee joint angles. The secondary outcome was the Comprehensive Osteoarthritis Test (COAT) total score.

Results: In the intention-to-treat analysis with an alpha-level of 0.05, 12-week application of the MKWs did not significantly reduce the mean absolute error (MAE) of JPS ( n = 18; P = 0.627); contrarily, the MAE was found to decrease significantly after wearing the sham MKWs ( n = 20; P = 0.01). The COAT total score gradually improved in both groups ( P < 0.05). When comparing the improvement of MAE and COAT total score at each follow-up between two groups, no significant differences were found; the maximal difference in the improvement of MAE between two groups was noted at week 12 (mean difference: 1.2°; 95% confidence interval −0.4 to 2.9; P = 0.144). In the per-protocol analysis, the study group showed better improvement in the COAT total score at week 12 ( P = 0.033).

Conclusion: The 35-mT MKWs could not significantly influence knee JPS in individuals with mild-to-moderate knee osteoarthritis.

Does bracing influence brain activity during knee movement: an fMRI study

Studies have shown that proprioceptive inputs during active and passive arm movements are processed in the primary and secondary somatosensory cortex and supplementary motor area of the brain. At which level of the central nervous system proprioceptive signals coming from the knee are regulated remains to be elucidated. In order to investigate whether there is a detectable difference in brain activity when various proprioceptive inputs are exerted at the knee, functional magnetic resonance imaging (fMRI) was used. fMRI in 13 healthy, right leg-dominant female volunteers compared brain activation during flexion-extension movements of the right knee under three different conditions: with application of a tight knee brace, with application of a moderate tight knee sleeve, and without application of a brace or sleeve. Brain activation was detected in the primary sensorimotor cortex (left and right paracentral lobule) and in the left superior parietal lobule of the brain. There was a significantly higher level of brain activation with the application of the brace and sleeve, respectively, compared to the condition without a brace or sleeve. A significantly higher cortical activation was also seen when comparing the braced condition with the condition when a sleeve was applied. The results suggest that peripheral proprioceptive input to the knee joint by means of a brace or sleeve seems to influence brain activity during knee movement. The results of this study also show that the intensity of brain activation during knee movement can be influenced by the intensity of proprioceptive stimulation at the joint.

Efficacy of 2 non-weight-bearing interventions, proprioception training versus strength training, for patients with knee osteoarthritis: a randomized clinical trial

STUDY DESIGN

Randomized clinical trial.

OBJECTIVE

To investigate the clinical and functional efficacy of 2 different non-weight-bearing exercise regimens, proprioceptive training (PrT) versus strength training (ST), for patients with knee osteoarthritis (OA).

BACKGROUND

Both strength and proprioceptive training are important interventions for individuals with knee OA. The benefits of weight-bearing exercises are generally recognized in the clinical setting. However, exercising in a standing or weight-bearing position may aggravate symptoms in patients with knee OA.

METHODS AND MEASURES

One hundred eight patients were randomly assigned to the PrT, ST, or no exercise (control) group for an 8-week intervention. Both the PrT and ST interventions consisted of non-weight-bearing exercises. Western Ontario and McMaster Universities Osteoarthritis Index-pain (WOMAC-pain) and -function scores, walking time on 3 different terrains, knee strength, and absolute knee reposition error were assessed before and after intervention. Data were analyzed using mixed-model ANOVAs.

RESULTS

Both PrT and ST significantly improved WOMAC-pain and -function score after intervention (P<.008). The improvement secondary to ST in the WOMAC-function scores (17.2 points) and for knee extension strength (10.3-14.9 Nm) was greater than the minimally clinically important difference for these measurements. The PrT group demonstrated greater improvement in walking time on a spongy surface and knee reposition error than the other 2 groups. No improvements were apparent in the control group.

CONCLUSION

Both types of non-weight-bearing exercises (PrT and ST) significantly improved outcomes in this study. PrT led to greater improvements in proprioceptive function, while ST resulted in a greater increase in knee extensor muscle strength.

The effects of a neoprene knee sleeve on subjects with a poor versus good joint position sense subjected to an isokinetic fatigue protocol

OBJECTIVES

It has been shown that muscle fatigue has a negative influence on proprioception. Several studies already have demonstrated improvement of proprioception by using knee sleeves.

HYPOTHESIS

Neoprene knee sleeves have different effects on the joint position sense in locally fatigued subjects with good or poor proprioceptive acuity.

DESIGN

A true experimental design with random assignment to intervention and control limbs.

SETTING

Military hospital, department of physical medicine and rehabilitation.

PARTICIPANTS

Sixty-four healthy subjects.

INTERVENTIONS

All subjects underwent four consecutive assessments of the same active joint-repositioning test under different conditions (braced, nonbraced, fatigued, and nonfatigued).

MAIN OUTCOME MEASUREMENTS

A three-way analysis of variance with repeated-measures design was conducted to investigate the effects of side (braced versus control side), assessment sequence (one to four), and proprioceptive acuity ("good" versus "poor"), and their interactive effect on the joint position sense.

RESULTS

Post hoc analysis revealed that only subjects with "poor" proprioceptive acuity benefit from the braced condition before the isokinetic fatigue protocol (P < 0.001). In contrast, all subjects benefit from the braced condition after the fatigue test.

CONCLUSIONS

Bracing is helpful in individuals with a poor baseline proprioceptive acuity in both fatigued and nonfatigued states. Subjects with a good joint position sense benefit from bracing only when in a fatigued state. The present findings suggest a rationale for using neoprene knee sleeves as a preventative measure or treatment in subjects and patients to enhance proprioceptive acuity in a fatigued state. Classification into "poor" and "good" proprioceptive acuity is only relevant in the nonfatigued condition.

Head and neck position sense

Traumatic minor cervical strains are common place in high-impact sports (e.g. tackling) and premature degenerative changes have been documented in sports people exposed to recurrent impact trauma (e.g. scrummaging in rugby) or repetitive forces (e.g. Formula 1 racing drivers, jockeys). While proprioceptive exercises have been an integral part of rehabilitation of injuries in the lower limb, they have not featured as prominently in the treatment of cervical injuries. However, head and neck position sense (HNPS) testing and re-training may have relevance in the management of minor sports-related neck injuries, and play a role in reducing the incidence of ongoing pain and problems with function. For efficacious programmes to be developed and tested, fundamental principles associated with proprioception in the cervical spine should be considered. Hence, this article highlights the importance of anatomical structures in the cervical spine responsible for position sense, and how their interaction with the CNS affects our ability to plan and execute effective purposeful movements. This article includes a review of studies examining position sense in subjects with and without pathology and describes the effects of rehabilitation programmes that have sought to improve position sense. In respect to the receptors providing proprioceptive information for the CNS, the high densities and complex arrays of spindles found in cervical muscles suggest that these receptors play a key role. There is some evidence suggesting that ensemble encoding of discharge patterns from muscle spindles is relayed to the CNS and that a pattern recognition system is used to establish joint position and movement. Sensory information from neck proprioceptive receptors is processed in tandem with information from the vestibular system. There are extensive anatomical connections between neck proprioceptive inputs and vestibular inputs. If positional information from the vestibular system is inaccurate or fails to be appropriately integrated in the CNS, errors in head position may occur, resulting in an inaccurate reference for HNPS, and conversely if neck proprioceptive information is inaccurate, then control of head position may be affected. The cerebellum and cortex also play a role in control of head position, providing feed-forward and modulatory influences depending on the task requirements. Position-matching tasks have been the most popular means of testing position sense in the cervical spine. These allow the appreciation of absolute, constant and variable errors in positioning and have been shown to be reliable. The results of such tests indicate that errors are relatively low (2-5 degrees). It is apparent that error is not consistently affected by age, a finding similar to studies undertaken in peripheral joints. Furthermore, the range of motion in which subjects are tested does not consistently affect accuracy in a predictable manner. However, it is evident that impairments in position sense are observed in individuals who have experienced whiplash-type injuries and individuals with chronic head and neck pain of non-traumatic origin (e.g. cervical spondylosis). While researchers advocate comprehensive retraining protocols, which include eye and neck motion targeting tasks and coordination exercises, as well as co-contraction exercises to reduce such impairments, some studies show that more general exercises and manipulation may be of benefit. Overall, there is limited information concerning the efficacy of treatment programmes.

A randomized controlled trial comparing the effectiveness of functional knee brace and neoprene sleeve use after anterior cruciate ligament reconstruction

BACKGROUND

Despite a lack of evidence for their effectiveness, functional knee braces are commonly prescribed to patients after anterior cruciate ligament (ACL) reconstruction.

PURPOSE

This trial was conducted to compare postoperative outcomes in patients using an ACL functional knee brace and patients using a neoprene knee sleeve.

HYPOTHESIS

Patients using a brace will have superior outcomes than those using a sleeve.

STUDY DESIGN

Randomized controlled clinical trial; Level of evidence, 1.

METHODS

One hundred fifty patients were randomized to receive a brace (n = 76) or neoprene sleeve (n = 74) at their 6-week postoperative visit after primary ACL reconstruction with hamstring autograft. Patients were assessed preoperatively, then 6 weeks and 6, 12, and 24 months postoperatively. Outcome measures included disease-specific quality of life (Anterior Cruciate Ligament-Quality of Life [ACL-QOL] Questionnaire), anterior tibial translation (KT-1000 arthrometer side-to-side difference), the single-limb forward hop test (limb symmetry index), and Tegner Activity Scale. Outcomes at 1 and 2 years were compared after adjusting for baseline scores. Subjective ratings of how patients felt while using the brace/sleeve were also collected for descriptive purposes using a questionnaire. Four a priori directional subgroup hypotheses were evaluated using tests for interactions.

RESULTS

There were no significant differences between brace (n = 62) and sleeve (n = 65) groups for any of the outcomes at 1- and 2-year follow-ups. Adjusted mean differences at 2 years were as follows: -0.94 (95% confidence interval [CI], -7.52 to 5.64) for the ACL-QOL Questionnaire, -0.10 mm (95% CI, -0.99 to 0.81) for KT-1000 arthrometer side-to-side difference, -0.87% (95% CI, -8.89 to 7.12) for hop limb symmetry index, and -0.05 (95% CI, -0.72 to 0.62) for the Tegner Activity Scale. Subjective ratings of confidence in the knee provided by the brace/sleeve were higher for the brace group than the sleeve group. Subgroup findings were minimal. Adverse events were few and similar between groups.

CONCLUSIONS

A functional knee brace does not result in superior outcomes compared with a neoprene sleeve after ACL reconstruction. Current evidence does not support the recommendation of using an ACL functional knee brace after ACL reconstruction.

Efficacy of a target-matching foot-stepping exercise on proprioception and function in patients with knee osteoarthritis

STUDY DESIGN

A randomized clinical trial design.

OBJECTIVE

To investigate the efficacy of high, repetitive, target-matching foot-stepping exercise (TMFSE) performed in a sitting position on proprioception, functional score, and walking velocity for patients with knee osteoarthritis (OA).

BACKGROUND

Researchers have suggested that exercises to address knee OA should include proprioceptive training. However, most patients cannot tolerate conventional proprioceptive training performed in a standing position.

METHODS AND MEASURES

Forty-nine subjects (mean age +/- SD, 63.3 +/- 8.1) with knee OA were randomly assigned to the exercise or no intervention groups. The exercise group practiced TMFSE in sitting, 3 sessions weekly for 6 weeks. All subjects underwent assessments of knee reposition error, functional incapacity score, and walking velocity prior to and after intervention.

RESULTS

The TMFSE significantly improved reposition error from a mean +/- SD of 3.0 degrees +/- 1.6 degrees to 1.5 degrees +/- 0.6 degree, walking velocity on ground level from 44.1 +/- 2.9 to 38.6 +/- 2.5 sec for 60 meters, time to complete a stairs task from 34.2 +/- 2.1 to 26.5 +/- 2.3 seconds, time to complete a figure-of-eight from 51.3 +/- 6.7 to 29.1 +/- 3.6 seconds, and score on a functional incapacity scale from 12.0 +/- 3.1 to 4.9 +/- 1.7, in subjects with knee OA after 6-week intervention (P <.0125). In contrast, the control group showed no change in any of the measured tests.

CONCLUSION

TMFSE in sitting appears to be an option for exercise in patients with mild to moderate knee OA. This may be an especially attractive option for patients who may have pain with weight-bearing exercises. A longitudinal study with a larger sample size is needed to confirm the potential use of TMFSE for patients with knee OA.

The effect of neoprene shorts on leg proprioception in Australian football players

Our purpose was to assess the effect of wearing close-fitting neoprene shorts on swinging leg movement discrimination (MD) scores in elite level Australian Football players. Twenty players had their swinging leg MD assessed using the active movement extent discrimination apparatus (AMEDA), once wearing close-fitting neoprene and once wearing loose-fitting running shorts. Subjects were randomly allocated to one of the shorts conditions prior to repeating the test in the other condition. The AMEDA was used to assess the accuracy at which subjects judge the extent of a standing backward swinging leg movement corresponding to the late swing early stance phase of running. Each subject performed 40 movements made to one of five randomly set physical limits, and without the aid of vision made a judgment as to the perceived limit position. From the accuracy of these judgments, a movement discrimination (MD) score was calculated for each subject under each condition. Subjects were grouped as having low or high neuromuscular control, or ability to use proprioception when controlling active movements without vision, based on their loose-shorts MD score. Analysis was performed on the MD scores obtained for each limb from subjects in the two groups, under the two shorts-wearing conditions. There was no main effect of wearing close-fitting shorts when the cohort was treated as a whole. A significant interaction effect was obtained (F=17.027, p=0.0006) whereby the mean MD score of the low neuromuscular control ability group was improved when wearing neoprene shorts but was reduced for the high ability group. Wearing close-fitting neoprene shorts has a beneficial effect on leg swing judgment accuracy in subjects with low neuromuscular control ability. Conversely, leg swing judgment accuracy for subjects with high ability was reduced by wearing neoprene shorts.

Current evidence and clinical applications of therapeutic knee braces

Braces are commonly used for the management of musculoskeletal injuries. With improvements in design and application, the knee brace has gained recognition by many as a treatment and prevention modality. However, there exist many different categories of knee braces, leading to confusion among many end users. The theoretical basis of the mechanism of action of the unloader, prophylactic, patellofemoral, and functional knee braces are explained in this review. This article also provides an update on the various knee braces in terms of the clinical efficacy and appropriate prescription recommendations.

Does arthroplasty type influence knee joint proprioception? A longitudinal prospective study comparing total and unicompartmental arthroplasty

Proprioception was assessed after knee replacement to compare total (TKA) to unicompartmental (UKA) knee arthroplasty. Thirty-four patients were recruited; seventeen patients underwent TKA and seventeen patients underwent UKA. The patient's age was similar in both groups. Two measures of proprioception, joint position sense (JPS) and postural sway (PS) were measured. Function was assessed using the Oxford Knee Score (OKS). Measurements were taken pre-operatively and 6 months post-operatively on both the operated and contralateral leg. Pre-operatively, no differences in JPS or PS were found between groups or between limbs in either group. Post-operatively, both groups had significant improvement of JPS in the operated limb only (20% increase). The improvement in JPS was similar in both groups. PS also improved significantly in both groups although the improvement of PS in the UKA group was twice that for the TKA group. The OKS improved by a similar amount in both groups. Both UKA and TKA result in a significant improvement in proprioception. Dynamic aspects of proprioception improve more after UKA than TKA, which may explain, in part, why UKA patients have superior functional outcome to that of TKA patients.

The Effect of a Neoprene Sleeve on Knee Joint Position Sense

The aims of the study were, first, to assess the effect of a neoprene knee brace on prop rioceptive acuity of normal subjects and, second, to assess the relationships between a variety of tests of proprioceptive acuity. Twenty healthy, physically active subjects had absolute error scores measured while carrying out three different established tests of proprioceptive ability (active tracking, active reproduction, and perceived angle tests) under two conditions, either with or without the presence of a neoprene sleeve. The neoprene sleeve significanltly improved the degree of error scores in all tests. For the active tracking, test accuracy was improved by 28% (p = 0.004), the angle reproduction test showed a 23% increase in accuracy (p = 0.029), and the accurancy of the perceived angle test improved by 27% (p = 0.035). The relationship between magnitude of error scores between the test all showed nonsignificant low correlation. The findings of this study support the previous literature, which indicates that the application of a knee sleeve improves proprioceptive acuity. The study also indicates that when testing proprioceptive acuity, a test battery should be used because of the limited correlatiotn between any of the tests used.

The effects of a 3-week use of lumbosacral orthoses on proprioception in the lumbar spine

STUDY DESIGN

Longitudinal, repeated-measures, factorial design. The trunk axial rotation repositioning error was the dependent variable, while the orthoses, test mode (passive versus active), and the testing session were the independent variables.

OBJECTIVES

To verify whether lumbosacral orthoses (LSOs) affect proprioception in the lumbar spine and whether these effects change over a 3-week period during which the LSO is consistently worn.

BACKGROUND

To date, there is no compelling evidence that lumbar orthoses support the spine. One hypothesis advanced by several authors is that they may enhance position sense (proprioception) in the lumbar spine.

METHODS AND MEASURES

Fourteen subjects without low back pain wore lumbosacral orthoses 3 hours a day for 3 weeks. Spine proprioception was tested in a seated posture in 3 sessions (days 0, 7, and 21).

RESULTS

A significant 3-way interaction was found between the effects of the orthoses, session, and test mode (P = .03). The ratio of passive to active average error indicated that after 3 weeks of wearing LSO, proprioception in the passive test worsened in relation to the active test with the LSO. In contrast, proprioception in the passive test improved in relation to the active test when performed without the LSO.

CONCLUSIONS

The LSO did affect proprioception in the lumbar spine. These effects most likely changed over time due to sensorimotor adaptation. However, no overall proprioceptive benefits could be ascertained from healthy subjects wearing the LSO.

Head and neck position sense in whiplash patients and healthy individuals and the effect of the cranio-cervical flexion action

BACKGROUND

Whiplash may damage structures within the neck that can affect position sense. Deep neck flexor muscle retraining may improve position sense. The current study compared range of motion and position sense in whiplash and control subjects and investigated the effects of a muscle training session on position sense.

METHODS

Twenty-three subjects with whiplash were compared with a matched control group. Range of motion and neck position sense measures were recorded using the 3-Space Fastrak. Measures of function were also assessed in the whiplash group. Subjects were then randomised into experimental and control groups and the former group received a training session to activate the deep neck flexor and scapular stabilising muscles (the cranio-cervical flexion action) during head and neck movements. After training, position sense measures were re-evaluated.

FINDINGS

Results showed significant reductions (P < 0.05) in active range of motion in the whiplash group when compared to the healthy group. No significant differences (P > 0.05) between whiplash and healthy groups in position matching accuracy were observed. Functional outcome scores indicated the whiplash group to be mildly disabled. No effect on error scores was observed when position-matching tasks were performed with and without the cranio-cervical flexion action. Correlations between functional measures or range of motion, and position sense were not significant.

INTERPRETATION

There was no evidence of position sense impairment in the mildly disabled whiplash subjects. The performance of the cranio-cervical flexion action had no effect on position sense, and hence clinical improvements observed from using this action may be more associated with mechanical stabilisation.

Effect of positioning and bracing on passive position sense of shoulder joint

OBJECTIVE

To examine the effects of positioning and sleeve type bracing on passive position sense of shoulder joints of healthy untrained subjects.

METHOD

A cross over study was carried out on 26 subjects (13 male, 13 female) with a proprioception measurement device. The selected method of testing was passive reproduction of a target angle. Both shoulder joints of all the subjects were evaluated with and without a compressive neoprene sleeve type of brace at two different start positions (45 degrees internal rotation, 75 degrees external rotation) with an angular rotational movement at a constant speed of 0.5 degrees /s. The angular displacements from the target angles at the end of the reproduction tests were recorded as position sense deficit scores.

RESULTS

The overall mean (SD) deficit score (0.99 (0.06)) was significantly (p<0.001) lower with the brace than without, and the overall mean deficit score was significantly (p<0.001) higher at the 45 degrees internal rotation start position than at the 75 degrees external rotation start position. However, there was no significant (p>0.05) interaction between brace application and start position.

CONCLUSION

Terminal limits of range of motion facilitate the position sense of shoulder joints. Compressive brace application improves the passive positioning sense possibly by stimulating cutaneous mechanoreceptors.

Dynamic upper limb proprioception in multidirectional shoulder instability

The ability of subjects with multidirectional shoulder instability to use proprioception to complete a series of upper limb repositioning tasks was investigated. Twelve subjects with multidirectional instability and 12 control subjects were blindfolded and instructed to use proprioception to reproduce a self-selected target position as accurately as possible. Subjects completed 10 repetitions for each limb using three distinct upper limb movements: overhead reaching, scapular plane pointing, and humeral external rotation with abduction. A three-dimensional video motion analysis system tracked limb position and determined spatial hand position error. Subjects with multidirectional shoulder instability showed significantly greater hand position error than control subjects. No hand position error differences were found between the symptomatic and the asymptomatic limbs of subjects in the instability group. Inter-repetition error for subjects in both groups improved significantly during the first three movement cycles. These results suggest that after movement initiation, dynamic proprioception was a factor in improving hand position accuracy in both groups, but to a lesser degree in subjects with multidirectional instability. Consequently, subjects with multidirectional instability may have a reduced capacity to use proprioception to refine and control the motor output of the upper limb.

The effect of a simulated knee joint effusion on postural control in healthy subjects

OBJECTIVE

To determine the effects of a simulated knee joint effusion on center of pressure (COP) path and mean power frequency (MPF) during standing.

DESIGN

Quasi-experimental design.

SETTING

Sports injury research laboratory in a university setting.

PARTICIPANTS

Twenty healthy volunteers, 10 of whom (age, 20.1+/-2.4y; height, 168.0+/-8.1cm; weight, 70.4+/-13.3kg) were assigned to an effusion group and 10 of whom (age, 25+/-3.8y; height, 169.4+/-8.9cm; weight, 74.7+/-7.7kg) were assigned to a control group.

INTERVENTIONS

COP data were collected before and after a 60-mL injection of sterile saline into the knee joint space.

MAIN OUTCOME MEASURES

COP path and mediolateral and anteroposterior MPF.

RESULTS

COP path decreased after the effusion (pre-effusion mean, 92.2+/-21.9cm; posteffusion mean, 77.27+/-23.0cm). No change was found within the control group for COP path (P>.05). No differences were detected before or after joint effusion when the MPF was examined (P>.05).

CONCLUSIONS

Possible explanations for the improved postural control after the effusion include additional somatosensory feedback, an augmented neural drive to the soleus, and/or increased capsular tension.

Kinesthesia at the knee: the effect of osteoarthritis and bandage application

OBJECTIVE

To investigate whether osteoarthritis (OA) of the knee or bandaging of the knee affects movement detection.

METHODS

Movement detection levels were determined in 10 women aged > 65 years with moderate to severe knee OA and 10 healthy women matched for age, body mass index, and activity levels. Movements were imposed at 0.5 degrees /second, 1.0 degrees /second, and 2.5 degrees /second. Additionally, detection levels were compared with and without the knee bandaged at a single velocity, (0.5 degrees /second).

RESULTS

Controls perceived significantly smaller movements than OA subjects at all test velocities (P < 0.01). However, the bandage did not affect movement detection (P > 0.05).

CONCLUSIONS

Detection of movement at the knee was impaired in subjects with severe knee OA, and a bandage did not improve detection. Thus, considering previous findings that position sense is impaired, a generalized proprioceptive deficit appears to be associated with OA. This deficit could result from loss of receptors, altered muscle function, or the consequent joint instability.

Characteristics of Shoulder-Position Sense: Effects of Mode of Movement, Scapular Support, and Arm Orientation

Context:

Although the repositioning test is widely used to evaluate proprioception, the effects of several test-associated variables on the test outcome are not known.

Objective:

To determine the effects of mode of movement, scapular support, and arm orientation on shoulder-position sense.

Participants:

49 healthy, randomly selected men.

Methods:

The repositioning test was conducted in 4 settings in which mode of movement, scapular support, and arm orientation were manipulated differently.

Main Outcome Measure:

Position-sense acuity was quantified as repositioning accuracy and consistency.

Results:

Active limb movement significantly enhanced repositioning accuracy and consistency compared with passive movement. Repositioning consistency was significantly better when the scapula was supported than when it was not. Arm orientation had no significant effect on repositioning accuracy and consistency.

Conclusion:

The protocol for evaluating or rehabilitating shoulder proprioception should include active limb movement with the scapula unsupported to ensure that it refects a patient’s proprioceptive demand during functional activities.

The role of weightbearing in the clinical assessment of knee joint position sense

Knee joint position sense was assessed by active tests with active limb matching responses in supine lying and in unilateral weightbearing (WB) stance using (re)positioning of the whole limb whilst focusing on the knee, and in supine lying using (re)positioning confined to the knee. Following five tests at approximately 45 degrees knee flexion in all three test conditions, position sense was found to be significantly more accurate and reliable following the WB procedure. Possible explanations are, first, that during WB the subjects were more able to assist identification of the test positions using cues obtained during movement of the knee to and from these positions. Second, a larger volume of proprioceptive afferent information may have been derived from sources outside the examined knee, and even outside the examined limb. Whilst WB joint position sense assessments are more functional, the obtained results may not characterise the capacity of the proprioceptors in and around the examined (knee) joint. Since the WB and NWB results were not correlated, one procedure cannot be used to predict results from the others. Also, predominantly unilateral WB stance is often impractical for subjects with limited balance or WB pain.

[Knee orthosis. First part : evaluation of physiological properties based on a review of the literature]

INTRODUCTION

The aim of this work was to proceed to a literature review to determine the physiological justifications underlying knee orthosis use in medical practice.

METHOD

An analysis of the international literature relating to the years 1980-2000 was carried out with the Medline data bank. We added extra articles focusing on the validity of the protocols used in the different evaluations.

RESULTS

Five hundred and twelve articles were selected and 46 articles of experimental validation were retained. The experimental protocols are divided into in vitro studies and clinical studies carried out in both healthy subject and patients. Only the in vitro experimental data allowed to reach strain values simulating traumatisms of the articular structures. They allowed to define the interest and limits of the orthosis according to articular physiology. Measurements carried out in vivo were effective to characterize the parameters of stability and proprioception and to discriminate between the orthosis. These studies correspond to experimental situations with related constraints that remain far below lesional constraints, focusing on their clinical validity.

CONCLUSION

This work point out many studies focusing on the physiological characterization of the knee orthosis. This evaluation of the orthosis through a single methodology remains difficult and justifies confrontation with clinical trials data.

The effects of joint angle and reliability on knee proprioception

PURPOSE

The purpose of this study was to examine the reliability and effects of knee angle on the detection and subsequent response to passive knee movement.

METHODS

Twenty college-aged male and 20 female volunteers were evaluated for proprioception by a newly developed perturbation test. Subjects were in a prone position on an isokinetic chair with their right lower leg attached to a freely moving resistance adapter. The knee was placed in a starting position of 15, 30, or 60 degrees of flexion. While relaxed, the knee was dropped into extension, and the subjects were instructed to "catch their leg" when movement was perceived. Five trials were completed at each angle, in a random order. An electrogoniometer was secured to the lateral portion of the knee in order to measure angular displacement after perturbation in two specific phases: detection (displacement from leg release to movement cessation) and response (displacement from movement cessation to peak knee flexion). A three-factor ANOVA (two repeated factors (knee angle and proprioception phase) and one between factor (gender)) was performed on the average and standard deviation of the five trials for significant main effects and interactions.

RESULTS

The results demonstrated a significant phase by angle interaction, and no gender effect. It was shown that at a more extended knee joint position (15 degrees), significantly less knee movement occurred before perception, followed by a greater response, than in a more flexed position (30 and 60 degrees).

CONCLUSION

The major findings of this study suggest that the detection of passive knee movement, and the subsequent voluntary response, may be dependent on joint angle. Considerations of the present method for proprioception assessment are warranted to enhance test-retest reliability.

Knee bracing after ACL reconstruction: effects on postural control and proprioception

PURPOSE

To evaluate the effects an anterior cruciate ligament (ACL) brace has on various measures of knee proprioception and postural control.

METHODS

Thirty subjects (mean age 27 +/- 11 yr) having undergone unilateral ACL reconstruction were tested with and without wearing their own custom-fit brace on their involved limb. Proprioception was assessed using joint angle replication tests completed on an isokinetic dynamometer. Postural control was assessed using a series of single-limb standing balance tests completed on a force platform. The balance tests included: 1) standing on the stable platform with eyes open, 2) standing on a foam mat placed over the platform with eyes open, 3) standing on the platform with eyes closed, and 4) standing on the platform after landing from a maximal single-limb forward hop.

RESULTS

The brace provided a small but statistically significant improvement in proprioception (mean reduction in error scores between target and reproduced angles = 0.64 +/- 1.4 degrees, P = 0.02). For the postural control tests, there was a significant brace condition by test situation interaction (P = 0.02), with the brace providing a small but statistically significant improvement during the test completed on the stable platform with eyes open (mean reduction in center of pressure path length = 4.2 +/- 8.4 cm, P = 0.02) but not during the other more challenging test situations. Additional post hoc analyses indicated that the relationship between knee proprioception and postural control measures were low and not significant (r = 0.003 to 0.19, P > 0.32), consistent with the suggestion that changes in knee proprioception can occur in the absence of substantial changes in postural control. Also, standing balance tests that challenged the somatosensory contribution to postural control (i.e., those completed on foam, or with eyes closed) were significantly related to single-limb forward hop distances (r = -0.4, P < 0.05), whereas performance during the proprioception test was not (r = 0.1, P > 0.50).

CONCLUSIONS

In general, bracing appears to improve performance during tasks characterized by relatively limited somatosensory input but not during tasks characterized by increased somatosenory input. The small magnitude of the improvements, coupled with their apparent lack of carry over to more difficult and functionally relevant tasks, questions the clinical benefit of the present effects of bracing.

Knee bracing for medial compartment osteoarthritis: effects on proprioception and postural control

OBJECTIVE

To evaluate the effects of a functional knee brace specifically designed for patients with varus gonarthrosis on measures of proprioception and postural control.

SUBJECTS

Fourteen men and six women (aged 59+/-9 yr) with measurable varus alignment and osteoarthritis of the knee medial compartment.

METHODS

Proprioception was assessed in the sitting position using an isokinetic dynamometer and was quantified as the ability to replicate target knee-joint angles. Postural control was assessed with a force platform using tests of single-limb standing balance performed, while the patient was standing on a stable surface and standing on foam, and was quantified as the total length of the path of the centre of pressure. All tests were performed with and without the patient's own custom-fit valgus brace.

RESULTS

Proprioception was significantly improved following application of the brace [mean difference=0.7 degrees, 95% confidence interval (CI)=0.2 to 1.1 degrees ). Postural control was not significantly affected by the use of the brace during the stable surface test (mean difference=2.6 cm, 95% CI=-4.3 to 9.5 cm) or the foam surface test (mean difference=0.9 cm, 95% CI=-7.5 to 9.4 cm).

CONCLUSION

Although enhanced proprioception may be partially responsible for reported improvements with the use of a brace, the present findings call into question the functional importance of the small changes observed.