Functional assessment of knee joint position sense following anterior cruciate ligament reconstruction

Sensorimotor Dysfunction Following Anterior Cruciate Ligament Reconstruction- an Afferent Perspective: A Scoping Review

Background

Sensorimotor dysfunction is thought to occur following anterior cruciate ligament (ACL) injury which may have implications on future reinjury risk. Dysfunction has been demonstrated within the efferent component of the sensorimotor system. However, no reviews have examined the two main components of the afferent system: the visual and somatosensory systems.

Hypothesis/Purpose

This study aimed to report differences in function (central processing and local processing) within the (1) somatosensory and (2) visual systems between individuals following anterior cruciate ligament reconstruction (ACLR) and healthy controls (between-subject). The study also aimed to report differences in function within the two systems between the two limbs of an individual following ACLR (within-subject).

Study Design

Scoping review.

Methods

A search was conducted in PubMed, SPORTDiscus, CINAHL, Medline and Embase up until September 2021. Level I-IV studies assessing somatosensory and visual systems were included if they compared ACLR limbs to the uninjured contralateral limb (within-subject) or a healthy control limb (between-group). The function of somatosensory and visual systems was assessed across both central processing (processing of information in the central cortex) and local processing (all other assessments outside of central processing of information).

Results

Seventy studies were identified (52 somatosensory, 18 visual). Studies examining somatosensory central processing demonstrated significant differences; 66% of studies exhibited within-subject differences and 100% of the studies exhibited between-group differences. Studies examining local somatosensory processing had mixed findings; 40% of the 'joint position sense (JPS)' and 'threshold to detect motion (TTDM)' studies showed significant within-subject differences (JPS=0.8°-3.8° and TTDPM=0.2°-1.4°) and 42% demonstrated significant between-group differences (JPS=0.4°-5° and TTDPM=0.3°-2.8°). Eighty-three percent of visual central processing studies demonstrated significant dysfunction between-groups with no studies assessing within-subject differences. Fifty percent of the studies examining local visual processing demonstrated a significant between-group difference.

Conclusion

Significant differences in central processing exist within somatosensory and visual systems following ACLR. There is mixed evidence regarding local somatosensory and visual processing. Increased compensation by the visual system and local visual processing dysfunction may occur in conjunction with somatosensory dysfunction.

Known-group validity of passive knee joint position sense: a comparison between individuals with unilateral anterior cruciate ligament reconstruction and healthy controls

BACKGROUND

Knee joint position sense (JPS) might be negatively affected after injuries to the anterior cruciate ligament (ACL). Recent systematic reviews suggest further investigation of psychometric properties, including validity, of knee JPS tests following ACL reconstruction (ACLR). This study investigated the known-group validity by comparing knee JPS errors between individuals who underwent unilateral ACLR and healthy controls.

METHODS

This cross-sectional study involved 36 men, including 19 after ACLR (ACLR group) and 17 healthy controls (control group). In both groups, the absolute error (AE), constant error (CE) and variable error (VE) of passive knee JPS were calculated in the flexion and extension directions, for two target angles (30° and 60° flexion) per direction. Discriminative validity was evaluated by comparing JPS errors between the operated and non-operated knees in the ACLR group. Known-group validity was evaluated by comparing JPS errors between the operated knees in the ACLR group and the asymptomatic non-dominant knees of healthy controls.

RESULTS

Mean AE, CE and VE for all tests were 4.1°, - 2.3° and 3.6° for the operated knees in the ACLR group, 5.5°, - 2.6° and 3.3° for the non-operated knees in the ACLR group and 4.6°, - 2.6° and 3.3° for the non-dominant knees in the control group, respectively, regardless of the test direction and target angle. The operated knees in the ACLR group did not show significantly greater JPS errors compared to the contralateral knees in the ACLR group and to the non-dominant knees in the control group (p ≥ 0.05). On the other hand, the non-operated knees showed significantly greater AE for the 0°-60° flexion test (p = 0.025) and CE for the 0°-30° flexion test (p = 0.024) than the operated knees in the ACLR group. JPS errors did not significantly differ in the operated knees in the ACLR group based on the direction of movement and the target angle. However, the errors were significantly higher when the knee was moved through a greater range compared to that of a lesser range between the starting and target angles.

CONCLUSION

The ACLR knees did not show greater passive JPS errors than the contralateral or control knees. The direction of movement and target angle did not influence the JPS acuity after ACLR. However, higher JPS errors were evident when the knee was moved through a greater range compared to a lesser range of motion. Further studies investigating the psychometric properties of standardized JPS tests following ACLR are warranted.

Reliability of the active knee joint position sense test and influence of limb dominance and sex

The output of a sensorimotor performance can be measured with the joint position sense (JPS) test. However, investigations of leg dominance, sex and quality measures on this test are limited. Therefore, these potential influencing factors as well as reliability and consistency measures were evaluated for angular reproduction performance and neuromuscular activity during the active knee JPS test in healthy participants. Twenty healthy participants (10 males; 10 females; age 29 ± 8 years; height 165 ± 39 cm; body mass 69 ± 13 kg) performed a seated knee JPS test with a target angle of 50°. Measurements were conducted in two sessions separated by two weeks and consisted of two blocks of continuous angular reproduction (three minutes each block). The difference between reproduced and target angle was identified as angular error measured by an electrogoniometer. During reproduction, the neuromuscular activity of the quadriceps muscle was assessed by surface electromyography. Neuromuscular activity was normalized to submaximal voluntary contraction (subMVC) and displayed per muscle and movement phase. Differences between leg dominance and sex were calculated using Friedman-test (α = 0.05). Reliability measures including intraclass correlation coefficient (ICC), Bland-Altman analysis (bias ± limits of agreement (LoA)) and minimal detectable change (MDC) were analysed. No significant differences between leg dominance and sex were found in angular error and neuromuscular activity. Angular error demonstrated inter-session ICC scores of 0.424 with a bias of 2.4° (± 2.4° LoA) as well as MDC of 6.8° and moderate intra-session ICC (0.723) with a bias of 1.4° (± 1.65° LoA) as well as MDC of 4.7°. Neuromuscular activity for all muscles and movement phases illustrated inter-session ICC ranging from 0.432 to 0.809 with biases between - 2.5 and 13.6% subMVC and MDC from 13.4 to 63.9% subMVC. Intra-session ICC ranged from 0.705 to 0.987 with biases of - 7.7 to 2.4% subMVC and MDC of 2.7 to 46.5% subMVC. Leg dominance and sex seem not to influence angular reproduction performance and neuromuscular activity. Poor to excellent relative reliability paired with an acceptable consistency confirm findings of previous studies. Comparisons to pathological populations should be conducted with caution.

Investigation of Body Awareness and Affecting Factors in Patients with Bariatric Surgery

BACKGROUND

Major weight loss after bariatric surgery (BS) makes the body sensitive to the environment. The factors associated with body awareness are unknown in patients with BS. In this study, we aimed to investigate the body awareness and the affecting factors in patients with BS.

METHODS

Our study included 81 patients who had BS at least 6 months ago and 40 people of the same age and gender who had not. Participants' body awareness was evaluated with the Body Awareness Questionnaire, body compositions with bioelectric impedance device, joint position sensation (JPS) with photography method, physical activity level with International Physical Activity Questionnaire, quality of life with the Short Form-36, depression status with the Beck Depression Inventory, and cognition with the Montreal Cognitive Assessment Scale. Mann-Whitney U and Chi-square tests were used for the comparison of the groups, and Spearman correlation analysis was used for in-group correlation analysis.

RESULTS

Body awareness was found to be higher in patients with BS compared to the control group (p = 0.002). Body awareness had a positive correlation with cognition (r = 0.277, p = 0.012), quality of life sub-scales (r = 0.245-0.374, p < 0.05), the amount of change in total body weight (r = 0.241, p = 0.027), and body mass index (BMI) (r = 0.269, p = 0.032); negative correlation with depression (r =  - 0.409, p = 0.016) and deviation in the JPS (r =  - 0.223, p = 0.046).

CONCLUSION

Body awareness of patients with BS was found to be high after surgery. Body awareness in patients with BS is associated with the amount of weight loss and BMI, depression, cognition, JPS, and health-related quality of life.

Effect of an Anterior Cruciate Ligament Rupture on Knee Proprioception Within 2 Years After Conservative and Operative Treatment: A Systematic Review with Meta-Analysis

BACKGROUND

The anterior cruciate ligament (ACL) plays a major role in knee proprioception and is thus responsible for maintaining knee joint stability and functionality. The available evidence suggests that ACL reconstruction diminishes somatosensory feedback and proprioceptive functioning, which are vital for adequate joint positioning and movement control.

OBJECTIVE

The aim of this systematic review and meta-analysis was to investigate the effect of an ACL rupture on knee proprioception after arthroscopic ACL repair surgery or conservative treatment.

METHODS

A systematic review with meta-analysis was conducted according to the Preferred Reporting Guidelines for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The literature search was performed in the following databases from inception to 10th October 2020: PubMed, Web of Science, SPORTDiscus, Cochrane Library and Scopus. Randomized and non-randomized studies that evaluated proprioception using the joint position sense (JPS) and threshold to detection of passive motion (TTDPM) techniques at 15°-30° knee flexion with an external healthy control group in a time period between 6 and 24 months post injury or operation were included in the analysis.

RESULTS

In total, 4857 studies were identified, from which 11 were included in the final quantitative analysis. The results demonstrated that proprioception after arthroscopic ACL repair surgery was significantly lower than in the healthy control group (JPS: standardized mean difference [SMD] 0.57, 95% confidence interval [CI] 0.27-0.87, p < 0.01, n = 6 studies; TTDPM: SMD 0.77, 95% CI 0.20-1.34, p < 0.01, n = 4 studies). There were no significant differences in proprioception between the conservative treatment group and the healthy control group (JPS: SMD 0.57, 95% CI - 0.69 to 1.84, p = 0.37, n = 4 studies; TTDPM: SMD 0.82, 95% CI - 0.02 to 1.65, p = 0.05, n = 2 studies), although measures for TTDPM were close to statistical significance.

CONCLUSION

The findings of the present systematic review and meta-analysis revealed that knee proprioception is persistently compromised 6-24 months following surgical treatment of ACL tears compared with healthy controls. The reduced kinesthetic awareness after ACL surgery is of high relevance for optimizing individual treatment plans in these patients. As the current literature is still scarce about the exact underlying mechanisms, further research is needed.

TRIAL REGISTRATION

The present systematic review was registered in PROSPERO (CRD42021198617).

Safety and Effectiveness of a Perturbation-based Neuromuscular Training Program on Dynamic Balance in Adolescent Females: A Randomized Controlled Trial

BACKGROUND

Adolescent females are at much greater risk for ACL injury than their male counterparts when participating in the same sports. Preventative and pre-operative rehabilitation neuromuscular (NM) exercise programs are often recommended to improve knee function and reduce injury rates. The effectiveness of perturbation-based NM training program has been established in an adult population but has yet to be investigated in the at-risk adolescent female population.

PURPOSE

To determine the effectiveness of a perturbation-based NM exercise program in a group of physically active adolescent females.

STUDY DESIGN

Prospective randomized trial.

METHODS

Twenty-four healthy and an exploratory group of 10 ACL-injured females (ages 12-18) were equally randomized into a perturbation-based NM training or control group and evaluated before and after a five-week intervention period. The primary outcome of dynamic balance was measured using the Y-Balance test (YBT); secondary outcome measures included lower limb strength, proprioception, and flexibility.

RESULTS

The perturbation-based NM training intervention was safely completed by all participants but had no significant effect on YBT scoring, lower limb strength, proprioception or flexibility in either the healthy or ACL-injured groups.

CONCLUSIONS

Perturbation-based NM training is safe, but may offer little preventative benefit for healthy or pre-operative rehabilitation benefit for ACL-injured adolescent females. Future research should examine whether the effectiveness of perturbation-based NM training is influenced by the length of the training intervention, training intensity, or when it is combined with other forms of prophylactic or pre-surgical rehabilitation frequently used with at-risk adolescent females who regularly participate in sport.

LEVEL OF EVIDENCE

Level 3.

Properties of Knee Joint Position Sense Tests for Anterior Cruciate Ligament Injury: A Systematic Review and Meta-analysis

Background:

Knee proprioception is believed to be deficient after anterior cruciate ligament (ACL) injury. Tests of joint position sense (JPS) are commonly used to assess knee proprioception, but their psychometric properties (PMPs) are largely unknown.

Purpose:

To evaluate the PMPs (reliability, validity, and responsiveness) of existing knee JPS tests targeting individuals with ACL injury.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

PubMed, Allied and Complementary Medicine, CINAHL, SPORTDiscus, Web of Science, Scopus, CENTRAL, and ProQuest databases were searched to identify studies that assessed PMPs of knee JPS tests in individuals with ACL injury. The risk of bias for each included study was assessed and rated at the outcome level for each knee JPS test. Overall quality and levels of evidence for each PMP were rated according to established criteria. Meta-analyses with mean differences were conducted using random effects models when adequate data were available.

Results:

Included were 80 studies covering 119 versions of knee JPS tests. Meta-analyses indicated sufficient quality for known-groups and discriminative validity (ACL-injured knees vs knees of asymptomatic controls and contralateral noninjured knees, respectively), owing to significantly greater absolute errors for ACL-injured knees based on a strong level of evidence. A meta-analysis showed insufficient quality for responsiveness, which was attributed to a lack of significant change over time after diverse interventions with a moderate level of evidence. Statistical heterogeneity (I² > 40%) was evident in the majority of meta-analyses. All remaining PMPs (reliability, measurement error, criterion validity, convergent validity, and other PMPs related to responsiveness) were assessed qualitatively, and they failed to achieve a sufficient quality rating. This was a result of either the study outcomes not agreeing with the statistical cutoff values/hypotheses or the level of evidence being rated as conflicting/unknown or based on only a single study.

Conclusion:

Knee JPS tests appear to have sufficient validity in differentiating ACL-injured knees from asymptomatic knees. Further evidence of high methodologic quality is required to ascertain the reliability, responsiveness, and other types of validity assessed here. We recommend investigations that compare the modifiable methodologic components of knee JPS tests on their PMPs to develop standardized evidence-based tests.

Development of supine and standing knee joint position sense tests

OBJECTIVES

We aimed to assess the test-retest reliability of a supine and standing knee joint position sense (JPS) test, respectively, and whether they discriminate knees with anterior cruciate ligament (ACL) injury from asymptomatic knees.

DESIGN

Repeated measures and cross-sectional.

SETTING

Research laboratory.

PARTICIPANTS

For test-retest reliability, 24 persons with asymptomatic knees. For discriminative analysis: 1) ACLR - 18 persons on average 23 months after unilateral ACL reconstruction, 2) CTRL - 23 less-active persons, and 3) ATHL - 21 activity level-matched athletes.

MAIN OUTCOME MEASURES

Absolute error (AE) and variable error (VE).

RESULTS

Test-retest reliability was generally highest for AE of the standing test (ICC 0.64-0.91). Errors were less for the standing compared to the supine test across groups. CTRL had greater knee JPS AE (P = 0.005) and VE (P = 0.040) than ACLR. ACLR knees showed greater VE compared to the contralateral non-injured knees for both tests (P = 0.032), albeit with a small effect size (η_p² = 0.244).

CONCLUSIONS

Our standing test was more reliable and elicited lesser errors than our supine test. Less-active controls, rather than ACLR, produced significantly greater errors. Activity level may be a more predominant factor than ACLR for knee JPS ∼2 years post-reconstruction.

Somatosensory Function Influences Aberrant Gait Biomechanics Following Anterior Cruciate Ligament Reconstruction

Osteoarthritis is common following anterior cruciate ligament reconstruction (ALCR), and aberrant gait biomechanics are considered a primary contributor. Somatosensory dysfunction potentially alters gait biomechanics, but this association is unclear. Therefore, the purposes of this investigation were to compare somatosensory function between limbs and evaluate associations between somatosensory function and gait biomechanics linked to osteoarthritis development in individuals with ALCR. Seventy-three volunteers with ALCR participated. Gait biomechanics (peak vertical ground reaction force magnitude and loading rate, peak internal knee extension and valgus moments, peak knee flexion and varus angles, and quadriceps/hamstrings co-activation) were assessed as subjects walked at their preferred speed. The somatosensory function was assessed via joint position sense error (knee flexion) and vibratory perception threshold (femoral epicondyles, malleoli, and first metatarsal). Though somatosensory function did not differ between the ACLR and contralateral limbs, poorer joint position sense in the ACLR limb was associated with lower loading rates and internal knee extension moments, and greater co-activation. Poorer vibratory perception at the medial and lateral malleoli and first metatarsal head in the ACLR limb was associated with lower loading rates, greater internal knee valgus moments and varus angles, and greater co-activation. Poorer vibratory perception at the medial malleolus and first metatarsal head in the contralateral limb was associated with greater peak knee varus angles and internal knee valgus moments. These results suggest that future research evaluating rehabilitation approaches for improving somatosensory function is warranted as a potential approach for restoring normal gait biomechanics and reducing osteoarthritis risk. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:620-628, 2020.

Evaluation of functional rehabilitation physiotherapy protocol in the postoperative patients with anterior cruciate ligament reconstruction through clinical prognosis: an observational prospective study

Background

The aim of the study was to evaluate the evolution of patients subject to physical treatment based on guidelines of functional rehabilitation after surgery anterior cruciate ligament reconstruction.

Methods

This is a prospective study of 177 patients with anterior cruciate ligament injury, who underwent surgery and physical therapy guideline conducted in an orthopedic clinic in São Paulo, southeastern Brazil. The clinical evolution of patients was made according to Lysholm and IKDC questionnaire on the 1st day after surgery with 30, 90 and 180 days of treatment.

Results

There was statistically significant increase in the gross values of Lysholm and IKDC questionnaires during the treatment (p < 0.001), which indicates progressive gain of function. According to the scores obtained from the IKDC, it can be observed that in stage 1 the average progress was 53.5 %, falling to 50 % in stage 2, and 26.1 % in stage 3. As to Lysholm score, it started with 87.7 %, falling to 62.6 % in the second stage and 7 % in the third stage, both statistically significant (p < 0.001). The rehabilitation-oriented functional objectives priority is to quickly get the exercises to gain breadth, strength and proprioception, optimizing and improving the integration of the athlete back to sport.

Conclusion

Synthesizing the gradual gain of function and according to clinical outcomes assessed by IKDC and Lysholm, the functional guideline presented may be considered an alternative for rehabilitation of patients in postoperative anterior cruciate ligament.

Strength does not influence knee function in the ACL-deficient knee but is a correlate of knee function in the and ACL-reconstructed knee

PURPOSE

Knee function, whether anterior cruciate ligament (ACL)-deficient or ACL-reconstructed, is related to many conditions, and no single biomechanical variable can be used to definitively assess knee performance. The purpose of this study was to investigate the relationship between extension and flexion muscle strength and knee function in patients prior and following ACL reconstruction.

METHODS

44 ACL-deficient patients with a mean age of 26.6 years were tested between 3 and 6 months following an acute injury and 2 years following ACL reconstruction. All reconstructed patients underwent surgical reconstruction within 6 months of ACL injury using bone-patellar tendon and interference screws. The Cincinnati knee rating system was used to assess knee function. Muscle strength was assessed with the Biodex™ Dynamometer. Isokinetic concentric and eccentric flexion and extension peak torque (Nm/kg) was tested at three different speeds: 60°/s, 120°/s and 180°/s. Isometric strength was tested in 30° and 60° of knee flexion. Both the involved and non-involved legs were tested to calculate symmetry indices.

RESULTS

The mean Cincinnati score in the ACL-deficient patient was 62.0 ± 14.5 (range 36-84) and increased to 89.3 ± 9.5 (range 61-100) in the ACL-reconstructed patient. Significant relationships between knee function and muscle strength in the ACL-deficient group were observed for knee symmetry indices (r = 0.38-0.50, p = 0.0001-0.05). In the ACL-reconstructed group significant relationships between knee functionality were observed for isometric and isokinetic peak torque of the involved limb (r = 0.46-0.71, p = 0.0001-0.007).

CONCLUSION

The findings of this study suggest that neither extension nor flexion peak torque were correlates of knee function in the ACL-deficient knee. However, leg symmetry indices were correlated to knee function. In the ACL-reconstructed knee, knee symmetry indices were not related to knee function but extension and flexion isokinetic concentric and isometric peak torque were.

Short-term effects of radiofrequency shrinkage treatment for anterior cruciate ligament relaxation on proprioception

OBJECTIVE

Radiofrequency (RF) shrinkage is used in anterior cruciate ligament (ACL) reconstruction. The present study investigated the therapeutic effects of RF on ACL relaxation and the probable influencing factors.

METHODS

Patients with ACL relaxation were included. Participants were randomly divided into two groups: a treatment group, in which patients were treated with RF shrinkage (RF group); a control group, in which patients received conventional surgical treatment. Thermal shrinkage was performed on ACL using an ArthroCare® CAPSure® wand. Lysholm scores, proprioceptive testing and Tegner activity scores were evaluated before and after treatment (at 6 and 12 months).

RESULTS

A total of 38 patients were included. The mean ± SD Lysholm score of those in the RF group at 12 months' post-treatment was significantly higher than in controls. The angle of deviation of the knee joint in RF group was significantly larger than in the control group at 6 months' post-treatment.

CONCLUSIONS

RF shrinkage treatment for ACL laxity could improve knee scores, and may affect proprioception and recovery of activity after surgery.

A systematic review to determine the reliability of knee joint position sense assessment measures

BACKGROUND

The assessment of joint position sense (JPS) is the most widely used measurement of knee proprioceptive capability within the literature. However, it remains unclear what the most reliable method is to assess this. The purpose of this study was to determine the intra- and inter-rater reliability of the various methods used to assess knee JPS.

METHODS

A systematic review of published and unpublished literature sources was conducted up to June 2012. All studies principally assessing the reliability (intra- or inter-rater) or reproducibility of a JPS of the knee were included. The methodological quality of each study was reviewed using the Critical Appraisal Skills Programme tool.

RESULTS

A total of 18 studies were eligible, assessing the reliability of JPS with 456 knees. The reliability of four methods of JPS has been recorded: position replication using a model, image recorded angulation, electrogoniometry and dynamometry/angular motion chair. Intra-rater reliability was good for the assessment of JPS using photographs and digital images, and replicating knee position using a paper model, this was good but variable when electrogoniometry was used, and moderate but variable when assessed using dynamometry/angle motion chairs. The assessment of JPS by image recorded angulation, electrogoniometry and dynamometry/angular motion chair has demonstrated good inter-rater reliability.

CONCLUSIONS

Whilst JPS methods appear to have variable reliability, the four assessment methods should be further assessed with pathological populations such as those following patellar dislocation or anterior cruciate ligament rupture. This will better facilitate the generalisability of JPS assessment methods to inform clinical practice.

Dynamic-position-sense impairment's independence of perceived knee function in women with ACL reconstruction

CONTEXT

There is conflicting evidence in the literature regarding whether women with anterior cruciate ligament reconstruction (ACLR) demonstrate impaired proprioception. This study examined dynamic-position-sense accuracy and central-nervous-system (CNS) processing time between those with and without long-term ACLR.

OBJECTIVE

To compare proprioception of knee movement in women with ACLR and healthy controls.

DESIGN

Cross-sectional.

SETTING

Human neuromuscular performance laboratory.

PARTICIPANTS

11 women (age 22.64 ± 2.4 y) with ACLR (1.6-5.8 y postsurgery) and 20 women without (age 24.05 ± 1.4 y).

INTERVENTIONS

The authors evaluated subjects using 3 methods to assess position sense. During knee flexion at pseudorandomly selected speeds (40°, 60°, 80°, 90°, and 100°/s), subjects indicated with their index finger when their knee reached a predetermined target angle (50°). Accuracy was calculated as an error score. CNS processing time was computed using the time to detect movement and the minimum time of angle indication. Passive and active joint-position sense were also determined at a slow velocity (3°/s) from various knee-joint starting angles.

MAIN OUTCOME MEASUREMENTS

Absolute and constant error of target angle, indication accuracy, CNS processing time, and perceived function.

RESULTS

Both subject groups showed similar levels of error during dynamic-position-sense testing, despite continued differences in perceived knee function. Estimated CNS processing time was 260 ms for both groups. Joint-position sense during slow active or passive movement did not differ between cohorts.

CONCLUSIONS

Control and ACLR subjects demonstrated similar dynamic, passive, and active joint-position-sense error and CNS processing speed even though ACLR subjects reported greater impairment of function. The impairment of proprioception is independent of post-ACLR perception of function.

Effects of cold water immersion on knee joint position sense in healthy volunteers

The purpose of this study was to determine the effects of cryotherapy, in the form of cold water immersion, on knee joint position sense. Fourteen healthy volunteers, with no previous knee injury or pre-existing clinical condition, participated in this randomized cross-over trial. The intervention consisted of a 30-min immersion, to the level of the umbilicus, in either cold (14 ± 1 °C) or tepid water (28 ± 1 °C). Approximately one week later, in a randomized fashion, the volunteers completed the remaining immersion. Active ipsilateral limb repositioning sense of the right knee was measured, using weight-bearing and non-weight-bearing assessments, employing video-recorded 3D motion analysis. These assessments were conducted immediately before and after a cold and tepid water immersion. No significant differences were found between treatments for the absolute (P = 0.29), relative (P = 0.21) or variable error (P = 0.86). The average effect size of the outcome measures was modest (range -0.49 to 0.9) and all the associated 95% confidence intervals for these effect sizes crossed zero. These results indicate that there is no evidence of an enhanced risk of injury, following a return to sporting activity, after cold water immersion.

Effects of joint effusion on proprioception in patients with knee osteoarthritis: a single-blind, randomized controlled clinical trial

OBJECTIVE

To assess the effects of joint effusion on proprioceptive status in patients with knee osteoarthritis (OA).

DESIGN

A single-blind, randomized, controlled clinical trial in 40 female subjects aged 50 years and over with painful knee OA. All subjects were randomly assigned to either the control or experimental group. A volume of 20 mL of normal saline was injected into the knee joint cavity of subjects in the experimental group under ultrasonographic guidance. Proprioceptive acuity was assessed by active repositioning of the lower limb using an electrogoniometer to measure knee joint position sense (JPS) under both non-weight-bearing (NWB) and weight-bearing (WB) conditions twice, with a 20-min rest interval. The experimental group performed the task twice (Test 1 and Test 2) before and within 5 min after joint infusion. The control group also performed Test 1 and Test 2 without joint infusion. The outcome of interest was the absolute angular error (AAE), ignoring the direction of the error, between the randomized target angle and the patient's reproduced angle of JPS values.

RESULTS

Compared with the control group, JPS was significantly compromised in the experimental group in the NWB test after joint infusion (P=0.025). However, no significant differences in the angular error were observed between Test 1 and Test 2 in the control group for the NWB or WB test or in the experimental group for the WB test after infusion (P>0.05).

CONCLUSIONS

This study showed that joint effusion impairs proprioceptive function in osteoarthritic knee joints.

Proprioception in anterior cruciate ligament deficient knees and its relevance in anterior cruciate ligament reconstruction

Injury to the anterior cruciate ligament (ACL) not only causes mechanical instability but also leads to a functional deficit in the form of diminished proprioception of the knee joint. "Functional" recovery is often incomplete even after "anatomic" arthroscopic ACL reconstruction, as some patients with a clinically satisfactory repair and good ligament tension continue to complain of a feeling of instability and giving way, although the knee does not sublux on clinical testing. Factors that may play a role could be proprioceptive elements, as the intact ACL has been shown to have significant receptors. Significant data have come to light demonstrating proprioceptive differences between normal and injured knees, and often between injured and reconstructed knees. ACL remnants have been shown to have proprioceptive fibers that could enhance functional recovery if they adhere to or grow into the reconstructed ligament. Conventionally the torn remnants are shaved off from the knee before graft insertion; modern surgical techniques, with remnant sparing methods have shown better outcomes and functional recovery, and this could be an avenue for future research and development. This article analyzes and reviews our understanding of the sensory element of ACL deficiency, with specific reference to proprioception as an important component of functional knee stability. The types of mechanoreceptors, their distribution and presence in ACL remnants is reviewed, and suggestions are made to minimize soft tissue shaving during ACL reconstruction to ensure a better functional outcome in the reconstructed knee.

Proprioceptive acuity assessment via joint position matching: from basic science to general practice

Over the past several decades, studies of use-dependent plasticity have demonstrated a critical role for proprioceptive feedback in the reorganization, and subsequent recovery, of neuromotor systems. As such, an increasing emphasis has been placed on tests of proprioceptive acuity in both the clinic and the laboratory. One test that has garnered particular interest is joint position matching, whereby individuals must replicate a reference joint angle in the absence of vision (ie, using proprioceptive information). On the surface, this test might seem straightforward in nature. However, the present perspective article informs therapists and researchers alike of multiple insights gained from a recent series of position matching studies by the author and colleagues. In particular, 5 factors are outlined that can assist clinicians in developing well-informed opinions regarding the outcomes of tests of position matching abilities. This information should allow for enhanced diagnosis of proprioceptive deficits within clinical settings in the future.

Foot position tends to be sensed as more medial than the actual foot position

Participants placed different parts of their foot as close as possible to a target line without stepping onto it while wearing modified goggles that obscured their view of their feet. Once they felt that their foot was appropriately placed, the distance between their foot and the target line was measured. Participants tended to step 20-30 mm over the target line when asked to place the most lateral part of their foot near the target line and tended to place their foot 20-30 mm away from the target line when asked to place the most medial part of their foot near the target line. These results indicate that the placed feet shifted more laterally than sensed, which may explain unexpected tripping during walking.

Mood and attitude predict pain outcomes following arthroscopic knee surgery

BACKGROUND

Decreased pain represents a clinically important outcome following arthroscopic knee surgery. However, little is known about preoperative mood and attitudinal factors and their potential relationship with pain outcomes.

PURPOSE

This prospective, longitudinal study investigated the influence of preoperative depression, stress, and optimism on pain severity and interference with functioning, controlling for relevant demographic and clinical factors 1 year postoperatively.

METHODS

Participants (N = 180, mean age = 48.2 years) completed scales assessing pain severity and interference both preoperatively and postoperatively. Demographics, depression, stress, optimism, and body mass index were assessed preoperatively. Physicians assessed extent of knee osteoarthritis during surgery.

RESULTS

Hierarchical regression analyses controlling for relevant demographic and clinical variables revealed that optimism and stress were significant predictors of pain severity at 1 year but not pain interference. Extent of osteoarthritis predicted pain interference.

CONCLUSIONS

These findings support that optimism and stress are important predictors of patient-rated pain severity. They do not, however, predict the extent to which pain interferes with daily functioning.