Proprioceptive Deficits Research Articles

Neuromuscular training improves knee proprioception in athletes with a history of anterior cruciate ligament reconstruction: A randomized controlled trial

BackgroundAthletes exhibit deficits in knee proprioception following anterior cruciate ligament reconstruction. Neuromuscular training programs improve knee proprioception in uninjured athletes; however, the effects on knee proprioception in athletes who have undergone anterior cruciate ligament reconstruction is not well understood. The purpose of this study was to examine the effects of a neuromuscular training program on knee proprioception in athletes who have returned to sport following anterior cruciate ligament reconstruction. MethodsTwenty-four male athletes, who had undergone anterior cruciate ligament reconstruction within the previous 6–12 months and returned to sport, participated in this randomized controlled trial. Athletes were randomly allocated to an experimental group (n = 12) that took part in an 8-week neuromuscular training program or a control group (n = 12) that simply continued their typical training routine. Knee position sense was assessed at baseline and after the 8-week period (post-testing). One-way analysis of covariance, with baseline performance included as a covariate, was used to compare knee position sense errors for the reconstructed limbs of the experimental and control groups at the post-testing time point. FindingsKnee position sense errors decreased by 51.7% for the experimental group and only 4.4% for the control group over the 8-week period. As a result, the experimental group demonstrated lower knee position sense errors, compared to the control group, at the post-testing time point (P < .001). InterpretationAthletes with a history of anterior cruciate ligament reconstruction may benefit from participation in a neuromuscular training program, even after completing post-operative rehabilitation.

Innovative methods measure the neural correlates of proprioception in multiple sclerosis.

The authors of the recently published article "Position sense deficits at the lower limbs in early multiple sclerosis: clinical and neural correlates" (Iandolo R, Bommarito G, Falcitano L, Schiavi S, Piaggio N, Mancardi GL, Casadio M, Inglese M. Neurorehabil Neural Repair 34: 260-270, 2020) provide strong evidence for the neural correlates leading to deficits in proprioception in multiple sclerosis. We believe their findings and innovative methodology show promise for how proprioception is measured in this and other clinical populations. We also suggest that further work should investigate the role of the corpus callosum in proprioceptive balance control.

Pilot Study to Measure Deficits in Proprioception in Children With Somatodyspraxia.

Given the importance of proprioception in motor coordination, the identification of sensory deficits contributing to motor challenges is crucial for appropriate intervention; however, objective proprioceptive tests are not currently available in pediatric clinical practice. To pilot test methods for assessing proprioception in children. Children with somatodyspraxia were predicted to have reduced proprioceptive awareness compared with age-matched control children. Observational study. Individual clinic. Ten children identified as having somatodyspraxia and 10 typically developing children, ages 6-8 yr. Spatial awareness and force perception were assessed by having the children match arm positions and grip and pinch forces using electronic dynamometers. All children were able to complete the proprioceptive assessments. Of those identified as having somatodyspraxia, 90% showed deficits in at least one area of proprioception. Children with somatodyspraxia performed more poorly on spatial awareness and force perception tests than typically developing children (p < .05). Children with dyspraxia have difficulties with spatial awareness and force perception, confirming a somatosensory contribution to dyspraxia. This article presents a framework and methods to measure proprioception in children. These methods will allow occupational therapy practitioners to quantify the proprioceptive deficits common in children with dyspraxia.

Limited Support for Trunk and Hip Deficits as Risk Factors for Athletic Knee Injuries: A Systematic Review With Meta-analysis and Best-Evidence Synthesis.

To determine whether neuromuscular deficits in trunk and hip-related function are risk factors for athletic knee injuries. Etiology systematic review with meta-analysis. Six online databases (MEDLINE, Web of Science, Embase, CINAHL, Scopus, and SPORTDiscus) were searched up to April 2019. Studies assessing trunk and hip neuromuscular function as risk factors for knee injuries in healthy athletic populations were included. Outcomes were synthesized quantitatively using meta-analysis of odds ratios, and qualitatively using best-evidence synthesis. Twenty-one studies met the inclusion criteria. There was very low-certainty evidence that greater hip external rotation strength protected against knee injuries (odds ratio = 0.78; 95% confidence interval: 0.70, 0.87; P<.05). There was limited evidence that deficits in trunk proprioception and neuromuscular control, and the combination of excessive knee valgus and ipsilateral trunk angle when landing unilaterally from a jump, may be risk factors for knee injuries. Most variables of trunk and hip function were not risk factors for injuries. Further research is required to confirm whether hip external rotation strength, trunk proprioception and neuromuscular control, and the combination of knee valgus angle and ipsilateral trunk control are risk factors for future knee injuries. J Orthop Sports Phys Ther 2020;50(9):476-489. Epub 1 Aug 2020. doi:10.2519/jospt.2020.9705.

Effect of Foot Strengthening Exercises in Osteoarthritis Knee

Background: Knee osteoarthritis is one of the leading cause of global disability. Patients with degenerative knee osteoarthritis clinically complain of pain, decreased muscle strength, joint instability, joint stiffness and proprioceptive deficits, all of which lead to a decrease in or loss of function. Foot pain is highly disabling, functional abilities and increases the risk of falls. Method: This was an experimental study with total of 33 subjects who had knee osteoarthritis with foot disability. Subjects of both genders with age group of 40 – 65 years fulfilling the inclusion and exclusion criteria participated. The outcome measure used was womac scale, for pain Visual analogue scale (VAS). Result:Statistical analysis of VAS, WOMAC and range of motion (ROM) were found to be extremely significant with a P value of &lt;0.0001. Conclusion: This study concluded that foot strengthening exercises were effective. It is proved from this study that foot strengthening exercises has significant effect on pain, range of motion and functional status of OA knee.

Effect of Chronic Ankle Sprain on Pain, Range of Motion, Proprioception, and Balance among Athletes.

Background: Ankle sprains are common among physically active individuals, especially among athletes. Majority of those who suffer ankle sprains have residual symptoms including pain, episodes of giving way, compromised proprioception and neuromuscular control, and re-injury leading to chronic ankle instability. The aim of this study was to see the effect of chronic ankle sprain on pain, range of motion, proprioception, and, static and dynamic balance among athletes. Methods: A total of 80 athletes, aged 18 to 25 years, involved in track-and-field sports were invited to participate in this study. They were divided in two groups. Athletes with history of grade 1 or 2 ankle sprain on either side requiring medical care who reported at least three episodes of ankle giving way in past 12 months were included in group A. An equal number of healthy athletes without any history of ankle sprain or injury in the lower limbs in the past one year matched by sex, age, height, weight, and limb dominance, were included in group B (control). Outcome measures: Participant’s pain, range of motion, proprioception and balance (static and dynamic) was measured using visual analog scale, half circle goniometer, degree of foot position sense, single leg stance time and Y-balance test respectively. Results: Although there were no differences in the active ankle joint range of motion (p > 0.05) in comparison to the control group, athletes with chronic ankle sprain reported mild pain and statistically significant (p < 0.05) deficits in foot proprioception, static and dynamic balance. Conclusions: Deficits in foot proprioception, static and dynamic balance even one year after the ankle sprain could be the reason for limitations in the dynamic defense system of the joint that predisposes to recurrent injury and instability. It is essential to understand the normal clinical course and risk factors for athletes who sustain sprain before devising a long term comprehensive rehabilitation program that focuses on mechanical and functional insufficiencies in order to improve their functional performance and prevent the risk of recurrent sprain.

Interrogating cortical representations in elite athletes with persistent posterior thigh pain – New targets for intervention?

ObjectivesHamstring injuries in athletes can lead to significant time away from competition as a result of persistent posterior thigh pain. These cases are often difficult to treat as the state of the tissues alone cannot explain symptoms. In non-athletic populations with persistent pain, disruptions to tactile, proprioceptive, and spatial cortical representations exist, which has led to promising brain-based treatments. Here, we explored whether athletes with persistent posterior thigh pain also display impairments in these cortical representations. DesignCross-sectional study. MethodsFourteen male professional athletes with persistent posterior thigh pain (‘Patients’) and 14 pain-free age, sport, body mass index and level-matched controls (‘Controls’) participated. The tactile cortical representation was assessed using two-point discrimination (TPD) threshold and accuracy of tactile localisation; the proprioceptive cortical representation was assessed using a left/right judgement task; spatial processing was assessed using an auditory detection task. ResultsTPD thresholds were similar for Patients and Controls (p=0.70). Patients were less accurate at localising tactile stimuli delivered to their affected leg, slower to make left/right judgements when the lower limb image corresponded to the side of their affected leg, and less accurate at detecting auditory stimuli delivered near their affected leg, when compared to their healthy leg or to the leg of Controls (p<0.01 for all). ConclusionsLeg-specific tactile, proprioceptive, and spatial processing deficits exist in athletes with persistent posterior thigh pain. That these processing deficits exist despite rehabilitation and normal tissue healing time suggests they may play a role in the persistence of posterior thigh pain.

Accuracy of selected neurological clinical tests in diagnosing MRI-detectable forebrain lesion in dogs.

This retrospective case study aims to evaluate the accuracy of menace response, response to nasal stimulation and proprioceptive placing in diagnosing forebrain lesion in dogs. A total of 145 client-owned dogs investigated by magnetic resonance imaging study of the brain between December 2017 and June 2019 were evaluated. Seventy-one dogs with no magnetic resonance imaging-detectable intracranial and significant cerebrospinal fluid abnormality or recent history of seizure (<48 h) served as controls. Binary regression analysis was performed to determine the sensitivity, specificity and likelihood ratios of each selected test. Older age at presentation was a significant risk factor for the presence of a forebrain lesion. Menace (62.5%) and proprioceptive deficits (40.5%) were common findings in all dogs. They were also significantly associated with the presence of forebrain abnormality. Moreover, they were more sensitive (77.3% and 82.2%, respectively) and specific (50.0% and 62.5%, respectively) when applied to dogs aged 6 years or older. Nonetheless, all of these tests' likelihood ratios, and thus reliability are poor. These neurological tests are commonly employed for diagnosing forebrain disease in dogs, yet are not highly accurate in diagnosing forebrain abnormality. Clinicians should interpret these clinical test results along with the patient history when designing a diagnostic plan.

Acuity of goal-directed arm movements and movement control; evaluation of differences between patients with persistent neck/shoulder pain and healthy controls

Background The main aim was to examine whether patients with persistent upper quadrant pain have higher end-point variability in goal directed pointing movements than pain-free controls when the pointing task is performed in total darkness and under full vision. An additional aim was to study associations between the magnitude of end-point variability and a clinical movement control test battery and self-rated functioning among patients. Methods Seventeen patients and 17 age- and gender-matched pain-free controls performed a pointing task that evaluated end-point variability of repetitive shoulder movements in horizontal adduction and abduction with full vision, and abduction with no visual information, completed a movement control test battery of neck and shoulder control tests and answered questionnaires. Results Patients had higher end point variability for horizontal abduction when performed with no visual information. For horizontal adduction the variability was higher, but only when it was controlled for movement time. No significant correlations were found between end-point variability and self-rated functioning, nor between end-point variability and neuromuscular control of the glenohumeral joint. Conclusions This study provides preliminary evidence that patients with persistent neck/shoulder pain can partly compensate proprioceptive deficits in goal-directed arm movement when visual feedback is present.

Effects Of Stroboscopic Vision On Postural Control In Individuals With And Without Chronic Ankle Instability

Chronic ankle instability (CAI) patients have consistently displayed postural control deficits. Previous research postulated that CAI patients rely more on the utilization of visual feedback than controls to compensate for the proprioceptive deficits after lateral ankle sprains. However, little is known about how reduced visual feedback would alter dynamic postural control in CAI patients relative to controls and copers. PURPOSE: To identify the effect of visual feedback disruption via stroboscopic glasses on dynamic postural control among groups of CAI, coper, and control. METHODS: 20 CAI (10M, 10F, 23.6±3.9 yr, 174.5±11.8 cm, 76.3±17.5 kg), 20 coper (10M, 10F, 22.2±1.4 yr, 176.4±10.2 cm, 69.3±10.9 kg), and 20 control (10M, 10F, 22.6±2.7 yr, 174.4±7.2 cm, 80.0±24.4 kg) subjects were categorized according to the Foot and Ankle Ability Measure (FAAM) and Modified Ankle Instability Index (MAII) questionnaires. Each subject performed three trials of a single-leg-hop stabilization test with eyes open (EO) and stroboscopic vision (SV). Force data (200 Hz) were collected using an in-ground force plate to calculate the dynamic postural stability index (DPSI) and directional stability indices (medial/lateral, anterior/posterior, vertical). Two-way repeated ANOVAs (group × condition) were used to examine the differences between condition (EO, SV) and group (CAI, coper, control). RESULTS: Visual condition main effect was driven by differences between EO and SV during dynamic postural control (p<0.001). Only CAI patients displayed altered DPSI scores between EO and SV (p=0.005). However, no differences were observed in copers (p=0.31) and controls (p=0.99). Regardless of visual condition, CAI patients displayed dynamic postural control deficits relative to controls (p=0.003) but no differences between CAI patients and copers (p=0.45). For the directional stability indices, each group displayed no differences between visual conditions. CONCLUSION: CAI patients rely more on visual feedback during dynamic postural control than copers and controls. However, they may have decreased ability to compensate for the disrupted visual feedback during dynamic movement. Stroboscopic glasses could be effective visual-disruption devices during dynamic movement tasks regardless of lateral ankle sprain history.

Multi-Ligament Knee Injuries in Elite Athletes: return to play rates, timing, and complications

Objectives:Historically, combined ligament injuries of the knee have been considered career ending for elite athletes. The objective of this paper was to provide a reference when counseling athletes and medical staffs in regards to outcomes following combined ligament knee injuries in elite athletes.Methods:A retrospective assessment of all elite athletes (professionals or amateurs at a national level) who had sustained a combined ligament knee injury in the period February 2001 to December 2015 was performed. Cases with a minimum of 2 ligaments needing surgery were included (of note, all medial collateral ligament (MCL) injuries were grade 3). The minimum follow up was 2 years. The outcomes recorded were: return to play or not, level of play returned to, time to return to play, and complications. This data was available in 100% of cases.Results:109 procedures were performed in 108 elite athletes. The mean age was 24.3 years old. Sports represented were: soccer (60 athletes), rugby (38 athletes), Judo (3 athletes), gymnastics (3 athletes), basketball (1 athlete), cricket (1 athletes), netball (1 athlete), and skiing (1 athlete). The distribution of injuries, rate of return to play and average return time can be seen in Figure 1. 40 of the 109 (36.7%) knees operated on underwent a minimum of one more surgical procedure during this period. The most common was manipulation under anesthesia (16 out of 109), followed by arthroscopic meniscectomy (9 out of 109). 2 out of 109 knees required revision ligament reconstruction.Conclusion:This study focuses on the ability to return to play, the level of play possible, and how long recovery takes, the factors most important to elite athletes. This study is unique and provides a reference point for future work, as well as being valuable to athletes and their medical and coaching teams.With such a large experience of these challenging injuries the senior author has learned key lessons. The only injuries that must have acute surgery (within first 2-3 weeks) are: those with a vascular lesion (rare in sport); irreducible dislocation (usually ‘button-holed’ medial femoral condyle); PLC structure injuries; and uncontrollable grade 3 PCL. With modern bracing much of the soft tissue envelope will heal- especially MCL tears of all grades and PCL grade 1 and 2. Early surgery, especially when it involves the MCL, has a high chance of stiffness requiring surgical intervention. The majority of injuries can be braced and safely dealt with when acute inflammation has resolved and motion is restored. Some injuries are best treated with staged surgery, specifically when the PLC is involved. Even in experienced hands, these cases often require subsequent procedures. It is critical to educate the patient and the team’s staff about this possibility at the onset of treatment. In addition, while the average return to play times range from 7-25 months, it takes at least 2-3 years to return to peak form due to the proprioceptive deficit sustained with these injuries. While these injuries can be career ending in elite sport, this case series shows that with modern treatment strategies and techniques, good results can be achieved in a high number of cases.Table 1. Injury Number Return to sport Return to same levelAve time taken (months)ACL + MCL3631 (86%)29 (81%)10.2ACL + PLC3933 (85%)26 (67%)12.9ACL + MCL + PLC43215ACL + PCL33212.3PCL + MCL44317.5PCL + PLC109 (90%)9 (90%)14.9MCL + PLC1114Bicruciate + MCL41113Bicruciate + PLC55318.2ACL/PCL/MCL/PLC33222PLC = Posterolateral corner

A dietary fatty acid counteracts neuronal mechanical sensitization

PIEZO2 is the essential transduction channel for touch discrimination, vibration, and proprioception. Mice and humans lacking Piezo2 experience severe mechanosensory and proprioceptive deficits and fail to develop tactile allodynia. Bradykinin, a proalgesic agent released during inflammation, potentiates PIEZO2 activity. Molecules that decrease PIEZO2 function could reduce heightened touch responses during inflammation. Here, we find that the dietary fatty acid margaric acid (MA) decreases PIEZO2 function in a dose-dependent manner. Chimera analyses demonstrate that the PIEZO2 beam is a key region tuning MA-mediated channel inhibition. MA reduces neuronal action potential firing elicited by mechanical stimuli in mice and rat neurons and counteracts PIEZO2 sensitization by bradykinin. Finally, we demonstrate that this saturated fatty acid decreases PIEZO2 currents in touch neurons derived from human induced pluripotent stem cells. Our findings report on a natural product that inhibits PIEZO2 function and counteracts neuronal mechanical sensitization and reveal a key region for channel inhibition.

Propriocepção do joelho em indivíduos submetidos à menistectomia parcial e à sutura meniscal: estudo observacional

INTRODUÇÃO: Os meniscos desempenham um papel fundamental na articulação, além de gerar estabilidade e congruência articular, influenciam na propriocepção do joelho. Lesões nesta estrutura muitas vezes só podem ser reparadas cirurgicamente, pelo fraco suprimento sanguíneo local, acarretando uma regeneração insatisfatória. A hipótese desse estudo é que possa existir menores déficits proprioceptivos em pacientes submetidos à sutura meniscal quando comparados aos submetidos à menistectomia parcial, devido a conservação da estrutura que tem importância proprioceptiva. OBJETIVO: Avaliar o déficit proprioceptivo do joelho em pacientes submetidos à menistectomia parcial e à sutura meniscal. METODOLOGIA: Estudo observacional transversal realizado na clínica de ortopedia e reumatologia da UNISA, em São Paulo. Participantes foram divididos em dois grupos. No Grupo I, indivíduos submetidos à menistectomia parcial, enquanto no Grupo II, a submetidos à sutura meniscal, sendo recrutados indivíduos de até 4 semanas de pós-operatório. Aprovado pelo comitê de ética seguido pelo CAAE 94144218.0.0000.0081. Para coleta dos dados foram realizados três testes: teste de senso de posicionamento ativo e passivo e teste de cinestesia. RESULTADOS: Participaram deste estudo uma amostra por conveniência de oito indivíduos (Grupo I, n=4 e Grupo 2, n=4), de ambos os gêneros, com média de idade de 33,4 anos (±11 anos). Os sujeitos do grupo I apresentaram maior déficit de proprioceptivo em comparação com o grupo II, nos testes realizados. Teste ativo do grupo I: 15°= 11,9° ±6,1; 30°= 11,6° ±5,0; 45°= 9,4° ±3,5 e do grupo II, 15°= 7,6° ±3,9; 30°= 6,9° ±2,8. Teste de Cinestesia: Grupo I 132ms ±51,5 vs Grupo II 96ms ±28,8). CONCLUSÃO: Os meniscos demonstraram ser estruturas influentes para a propriocepção do joelho, apresentando maiores déficits em indivíduos que retiraram a estrutura.

Proprioception deficiency in articular cartilage lesions of the knee

ABSTRACTPurposeThe purpose of this study is to investigate the proprioceptive function of patients with isolated articular cartilage lesions of the knee as compared to normal controls.MethodsThe Cartilage group consisted of eight subjects with radiologically and arthroscopically confirmed, isolated, unilateral, articular cartilage lesions of the knee (Outerbridge grade III or IV). They were compared to 50 normal controls. Knee proprioception was assessed by dynamic postural stabilometry using the Biodex Balance SD System. Patient-reported outcome measures (PROMs) were used to evaluate all subjects.ResultsProprioception of the injured knee of the Cartilage group was significantly poorer compared to that of the control group (p < 0.001). A significant proprioceptive deficit also was observed when the uninjured knees of the Cartilage group were compared to those in the Control group (p = 0.003). There was no significant proprioceptive difference between the injured and the contra-lateral uninjured knee of the Cartilage group (p = 0.116). A significant correlation was found between the proprioception measurements of the injured and uninjured knee of the Cartilage group (r = 0.76, p = 0.030). A significant difference was observed in all PROMs (p < 0.001) between the Cartilage and Control groups.ConclusionsPatients with isolated articular cartilage lesions of the knee had a significant proprioceptive deficit as compared to normal controls. The deficiency was profound and even affected the proprioceptive function of the contra-lateral uninjured knee. This study has shown that articular cartilage lesions have a major influence on knee proprioception. However, it remains uncertain as to whether a proprioceptive deficit leads to osteoarthritis or is a consequence of it.

Utilizing the somatosensory system via vibratory stimulation to mitigate knee pain during walking: Randomized clinical trial

BackgroundPain and proprioception deficits are often associated with knee pathologies and resultant quadriceps muscle inhibition. There is a need for new approaches to mitigate active knee pain and restore muscle function during walking. Activating properties of the somatosensory system with common pain and sensory pathways offers a novel opportunity to enhance quadriceps function during walking. Research questionConduct a controlled clinical trial that investigates the effects of applying intermittent vibrational cutaneous stimulation during walking on knee pain and symptoms and their correlations to gait parameters. MethodsThis longitudinal controlled cross-over clinical study included thirty-two patients randomly and blindly assigned to active Treatment A and passive Treatment B for 4 weeks with a 2-week washout period between treatments. ResultsSubjects when wearing active Treatment A for 4 weeks had significant (p = 0.04) improvement in patient reported outcomes, while they had no significant differences with passive Treatment B (p > 0.7) compared to the no treatment condition. For Treatment A, subjects with low knee flexion moment and knee flexion angle in no-treatment condition exhibited the greatest increase in knee flexion moment/angle in the active treatment condition (R > 0.57, p < 0.001). These changes in gait measures were correlated significantly to changes in pain. SignificanceThis clinical trial indicates that knee pain can be reduced, and gait improved in a manner that enhances quadriceps function by applying intermittent cutaneous stimulation during gait in patients following knee injury or disease. The correlation between decreased pain and improved gait suggests that rehabilitation and exercise therapy may benefit from this treatment.

Quantitative assessment of proprioceptive dysfunction in cancer survivors post oxaliplatin-containing chemotherapy.

e24071 Background: Oxaliplatin (OX) is commonly used for gastrointestinal cancers but can cause chronic neurotoxicity with long-term motor impairments (e.g. dexterity loss, poor balance, and falls). These impairments are often attributed to OX-induced sensory neuropathy that disrupts touch, vibration, and proprioception in distal limbs. However, some cancer survivors report motor impairments even in the absence of sensory neuropathy. Recent animal studies suggest OX induces global signaling dysfunction in muscle proprioceptors that may account for the motor impairments in the absence of sensory neuropathy. However, this mechanism has yet to be investigated in cancer survivors. We hypothesize that cancer survivors will display impaired proprioceptive function compared to age-matched healthy controls using quantitative techniques that are more sensitive than current clinical measures. Methods: We assessed use of proprioception for controlling upper extremity position, force, and posture using target reaching, force matching, and postural stability tasks, respectively. A haptic robot quantified motor performance in all tasks, performed with and without visual feedback to disambiguate proprioceptive from vision. The dominant hand and wrist were fixed in an orthosis emphasizing elbow and shoulder use since these joints are less likely to have sensory neuropathy. Self-reported symptoms and functional limitations were measured with the QLQ-CIPN20 questionnaire. Accuracy and trial-to-trial variability for each task were compared between cancer survivors and controls using linear mixed effect models. Results: Thirteen cancer survivors (0 – 20 months post OX-treatment) and 7 controls completed the study. Without visual feedback, cancer survivors had significantly decreased accuracy (p &lt; 0.001) and increased trial-to-trial variability (p &lt; 0.05) in all tasks compared to controls. Deficits in force matching were correlated with self-reported motor dysfunction on the QLQ-CIPN20 (r = 0.87, p &lt; 0.001). Conclusions: Proprioceptive deficits occur in cancer survivors who received OX-treatment and are associated with motor dysfunction. This identified mechanism of motor impairment may present opportunities for targeted interventions.

The anatomo-clinical picture of the pathological embodiment over someone else's body part after stroke

Recently, a monothematic delusion of body ownership due to brain damage (i.e., the embodiment of someone else's body part within the patient's sensorimotor system) has been extensively investigated. Here we aimed at defining in-depth the clinical features and the neural correlates of the delusion. Ninety-six stroke patients in a sub-acute or chronic phase of the illness were assessed with a full ad-hoc protocol to evaluate the embodiment of an alien arm under different conditions. A sub-group of seventy-five hemiplegic patients was also evaluated for the embodiment of the movements of the alien arm. Fifty-five patients were studied to identify the neural bases of the delusion by means of voxel-based lesion-symptom mapping approach. Our results show that, in forty percent of the whole sample, simply viewing the alien arm triggered the delusion, but only if it was a real human arm and that was seen from a 1st person perspective in an anatomically-correct position. In the hemiplegic sub-group, the presence of the embodiment of the alien arm was always accompanied by the embodiment of its passive and active movements. Furthermore, the delusion was significantly associated to primary proprioceptive deficits and to damages of the corona radiata and the superior longitudinal fasciculus. To conclude, we show that the pathological embodiment of an alien arm is well-characterized by recurrent and specific features and might be explained as a disconnection deficit, mainly involving white matter tracts. The proposed exhaustive protocol can be successfully employed to assess stroke-induced disorders of body awareness, unveiling even their more undetectable or covert clinical forms.

Impact of Prolonged Tablet Computer Usage with Head Forward and Neck Flexion Posture on Pain Intensity, Cervical Joint Position Sense and Balance Control in Mechanical Neck Pain Subjects

The prolonged head forward and neck flexion posture associated with tablet computer use is a known risk factor for neck pain. Neck pain related dysfunction may cause proprioceptive errors and deficits in balance control. Thus, this study aimed to investigate the impact of prolonged tablet computer use with head forward and neck flexion posture on the pain intensity, cervical position sense and balance control in mechanical neck pain patients. The prolonged head forward and neck flexion posture associated with tablet computer use is a known risk factor for neck pain. Neck pain related dysfunction may cause proprioceptive errors and deficits in balance control. Thus, this study aimed to investigate the impact of prolonged tablet computer use with head forward and neck flexion posture on the pain intensity, cervical position sense and balance control in mechanical neck pain patients.The prolonged head forward and neck flexion posture associated with tablet computer use is a known risk factor for neck pain. Neck pain related dysfunction may cause proprioceptive errors and deficits in balance control. Thus, this study aimed to investigate the impact of prolonged tablet computer use with head forward and neck flexion posture on the pain intensity, cervical position sense and balance control in mechanical neck pain patients. Twenty subjects with mechanical neck pain (24.1 ± 3.4 years) and 20 healthy controls (23.7 ± 3.3 years) were recruited from a university environment. A neck pain inducing protocol simulating prolonged tablet computer usage with neck flexion posture was performed by the mechanical neck pain subjects until the point of moderate pain. The neck pain related scores, cervical range of motion and neck tissue hardness were evaluated in both the healthy controls and the neck pain subjects before the neck pain inducing protocol. Differences in the cervical joint position sense, neck tissue hardness and static standing balance performance of the healthy controls and mechanical neck pain subjects were investigated after the neck pain inducing protocol. The mechanical neck pain subjects demonstrated a lower cervical range of motion and a harder neck tissue status than the control subjects. The pain intensity reported by the neck pain subjects after the neck pain inducing protocol was similar to that experienced by the subjects in previous pain attacks. Significant differences in the absolute neck joint positioning error were observed between the mechanical neck pain group and the control group. Prolonged tablet computer use with head forward and neck flexion posture did not significantly increase the joint positioning error in the mechanical neck pain group. However, prolonged tablet computer use with head forward and neck flexion posture resulted in a poorer static standing balance performance in the subjects with mechanical neck pain than in the healthy controls. The subjects with mechanical neck pain exhibited a decreased cervical range of motion, a harder neck tissue status and greater neck joint position errors than the healthy controls. In addition, prolonged tablet computer use with head forward and neck flexion posture reproduced the neck pain severity and reduced the balance control ability of the mechanical neck pain subjects.

Comparison of proprioception between osteoarthritic and age-matched unaffected knees: a systematic review and meta-analysis.

Theoretically, proprioceptive acuity could decrease in patients with knee osteoarthritis. However, there have been conflicting results in terms of proprioceptive deficit in osteoarthritic knees. The purpose of this systematic review and meta-analysis was to compare knee proprioception between osteoarthritic and healthy control knees. Studies comparing proprioception in osteoarthritic and healthy knees of age-matched control group using thresholds to detect passive motion (TTDPM) or joint position sense (JPS) tests were identified. JPS was assessed by measuring the reproduction of passive positioning (RPP) or active positioning (RAP) of the knees. Seventeen studies were finally included in this meta-analysis. The pooled results of the analyses of the TTDPM for both 30° and 45° knee flexion showed that the mean angle of error was 0.83° greater (95% confidence interval: 0.44 to 1.23°; p < 0.001) in the osteoarthritic knees than in control knees. The pooled data of the RAP and RPP also showed that the mean angle of error was 1.89° greater in the osteoarthritic knees than in the control group. The mean difference in the angle of error between the osteoarthritic knees and control group was 1.06° greater in the JPS test than in the TTDPM (p < 0.001). The knee proprioceptive acuity of the patients with knee osteoarthritis was poorer than that of the patients with unaffected knees in the age-matched control group both in terms of the TTDPM and JPS; clinical relevance of these deficits needs to be clarified in further studies. Meta-analysis, Level II.

C1 Hemilaminectomy for Resection of Foramen Magnum Meningioma: 2-Dimensional Operative Video.

We present a case of a sizeable foramen magnum meningioma that was resected through a C1 hemilaminectomy in prone (concorde) position. The patient is a 51-year-old woman with a 3-month history of progressive paresthesia of the upper and lower extremities, followed by gait disturbance, and hand apraxia. There was no complaint of nuchal pain.On magnetic resonance imaging (MRI) a briskly enhancing extra-axial, intradural craniospinal lesion, extending from the basion of the lower clivus, over the tectorial membrane to the middle of the axis' body was discovered. There was significant transposition and compression of the medulla and corresponding focal hyperintensity on T2-weighted imaging.On physical examination, the patient was ambulatory independently, notwithstanding a pronounced spinal ataxia. There were deficits in sensation and proprioception, as well as urinary retention, but preserved function of the lower cranial nerves.In view of the profound transposition of the medulla, utilization of the corridor created by the tumor seemed feasible and we felt that a limited C1 hemilaminectomy would provide sufficient microsurgical access thus obviating a more extensive and invasive approach to the craniocervical junction.A gross-total resection was achieved; histopathology confirmed a World Health Organization (WHO) grade I angiomatous meningioma with a low-proliferation index. The patient was discharged home 3 days after surgery and her spinal ataxia resolved completely within 3 months of out-patient rehabilitation. At 3-year follow-up, there was no indication of residual or recurrence. The link to the video can be found at: https://youtu.be/WyShbfr-xi0 .