Lateral wedge insoles for medial knee osteoarthritis: effects on lower limb frontal plane biomechanics

Background

Lateral wedges reduce the peak knee adduction moment and are advocated for knee osteoarthritis. However some patients demonstrate adverse biomechanical effects with treatment. Clinical management is hampered by lack of knowledge about their mechanism of effect. We evaluated effects of lateral wedges on frontal plane biomechanics, in order to elucidate mechanisms of effect.

Methods

Seventy three participants with knee osteoarthritis underwent gait analysis with and without 5° lateral wedges. Frontal plane parameters at the foot, knee and hip were evaluated, including peak knee adduction moment, knee adduction angular impulse, center of pressure displacement, ground reaction force, and knee-ground reaction force lever arm.

Findings

Lateral wedges reduced peak knee adduction moment and knee adduction angular impulse (− 5.8% and − 6.3% respectively, both P < 0.001). Although reductions in peak moment were correlated with more lateral center of pressure (r = 0.25, P < 0.05), less varus malalignment (r values 0.25-0.38, P < 0.05), reduced knee-ground reaction force lever arm (r = 0.69, P < 0.01), less hip adduction (r = 0.24, P < 0.05) and a more vertical frontal plane ground reaction force vector (r = 0.67, P < 0.001), only reduction in knee-ground reaction force lever arm was significantly predictive in regression analyses (B = 0.056, adjusted R² = 0.461, P < 0.001).

Interpretation

Lateral wedges significantly reduce peak knee adduction moment and knee adduction angular impulse. It seems a reduced knee-ground reaction force lever arm with lateral wedges is the central mechanism explaining their load-reducing effects. In order to understand why some patients do not respond to treatment, future evaluation of patient characteristics that mediate wedge effects on this lever arm is required.     

Effects of a hip brace on biomechanics and pain in people with femoroacetabular impingement

Objectives

This study evaluates whether hip bracing in patients with femoroacetabular impingement (FAI) (a) immediately reduces range of hip internal rotation, flexion, adduction, and pain during functional tasks; and (b) improves patient-reported outcomes when worn daily over 4 weeks.

Prostaglandin E(2) modulates TTX-R I(Na) in rat colonic sensory neurons

This study was performed to determine the impact of the inflammatory mediator prostaglandin E(2) (PGE(2)) on the biophysical properties of tetrodotoxin resistant voltage-gated Na(+) currents (TTX-R I(Na)) in colonic dorsal root ganglion (DRG) neurons. TTX-R I(Na) was studied in DRG neurons from thoracolumbar (TL: T(13)-L(2)) and lumbosacral (LS: L(6)-S(2)) DRG retrogradely labeled following the injection of DiIC(18) (DiI) into the wall of the descending colon of adult male rats. TTX-R I(Na) in colonic DRG neurons had a high threshold for activation [V(0.5) of conductance-voltage (G-V) curve = -3.1 +/- 1.0 (SE) mV] and steady-state availability (V(0.5) for H-infinity curve = -18.4 +/- 1.4 mV), was slowly inactivating (10.6 +/- 1.4 ms at 0 mV), and recovered rapidly from inactivation (83.5 +/- 5.0% of the current recovered with a time constant of 1.3 +/- 0.1 ms at -80 mV). TTX-R I(Na) was present in every colonic DRG neuron studied (n = 62). PGE(2) induced a rapid (<15 s) increase in TTX-R I(Na) that was associated with a hyperpolarizing shift in the G-V curve (3.4 +/- 0.7 mV), an increase in the rate of inactivation (4.21 +/- 0.7 ms at 0 mV), and no change in steady-state availability. There was no statistically significant difference (P > 0.05) between TL and LS colonic DRG neurons with respect to the biophysical properties of TTX-R I(Na), the current density or the magnitude of PGE(2)-induced changes in the current. However, both the proportion of TL and LS neurons in which TTX-R I(Na) was modulated by PGE(2) (16 of 16 TL neurons and 12 of 14 LS neurons) as well as the magnitude of PGE(2)-induced changes in the current were significantly larger in colonic DRG neurons than in the total population of DRG neurons. These results suggest that changes in nociceptive processing associated with inflammation of the colon does not reflect differences between TL and LS neurons with respect to the properties of TTX-R I(Na), distribution of current, or magnitude of inflammatory mediator-induced changes in the current. However, these results do suggest modulation of TTX-R I(Na) in colonic afferents is an underlying mechanism of hyperalgesia and pain associated with inflammation of the colon and that this current constitutes a novel target for therapeutic relief of visceral inflammatory pain.     

Decolonisation for health: A lifelong process of unlearning for Australian white nurse educators

Indigenous nurse scholars across nations colonised by Europeans articulate the need for accomplices (as opposed to mere performative allies) to work alongside them and support their ongoing struggle for health equity and respect and to prioritise and promote culturally safe healthcare. Although cultural safety is now being mandated in nursing codes of practice as a strategy to address racism in healthcare, it is important that white nurse educators have a comprehensive understanding about cultural safety and the pedagogical skills needed to teach it to undergraduate nurses. We open this article with stories of our journeys as two white nurses in becoming accomplices and working alongside Indigenous Peoples, as patients and colleagues. Our lived experience of the inertia of healthcare and education organisations to address systemic and institutional resistance to the practice of cultural safety underpins the intention of this article. We understand that delivering this challenging and complex topic effectively and respectfully is best achieved when Indigenous and white educators work together at the cultural interface. Doing so requires commitment from white nurses and power holders within universities and healthcare institutions. A decolonising approach to nurse education at individual and institutional levels is fundamental to support and grow the work that needs to be done to reduce health inequity and increase cultural safety. White nurse accomplices can play an important role in teaching future nurses the importance of critical reflection and aiming to reduce power imbalances and racism within healthcare environments. Reducing power imbalances in healthcare environments and decolonising nursing practice is the strength of a cultural safety framework.     

New evidence for preserved somatosensory pathways in complete spinal cord injury: A fMRI study

Trauma to the spinal cord rarely results in complete division of the cord with surviving nerves sometimes remaining silent or failing to function normally. The term motor or sensory discomplete has been used to describe this important but unclassified subgroup of complete SCI. Importantly, silent motor or sensory pathways may contribute to aversive symptoms (spasticity, pain) or improved treatment success. To demonstrate more objectively the presence of subclinical preserved somatosensory pathways in clinically complete SCI, a cross‐sectional study using functional MRI (fMRI) was undertaken. The presence of brain activation following innocuous brushing of an insensate region below‐injury (great toe) was analyzed in 23 people (19 males (83%), mean ± SD age 43 ± 13 years) with clinically complete (AIS A) SCI with (n = 13) and without (n = 10) below‐level neuropathic pain and 21 people without SCI or pain (15 males (71%); mean ± SD age 41 ± 14 years). Location appropriate, significant fMRI brain activation was detected in 48% (n = 11/23) of subjects with clinically complete SCI from below‐injury stimulation. No association was found between the presence of subclinical sensory pathways transmitting innocuous mechanical stimuli (dorsal column medical lemniscal) and below‐level neuropathic pain (χ² = 0.034, P = 0.9). The high prevalence of sensory discomplete injuries (～50% complete SCI) strengthens the case to explore inclusion of this category into the international SCI taxonomy (ISNCSCI). This would ensure more widespread inclusion of discomplete SCI in ongoing pain and motor recovery research. Neurophysiological tests such as fMRI may play a role in this process. Hum Brain Mapp 39:588–598, 2018. © 2017 Wiley Periodicals, Inc.     

Cartilage morphology at 2–3 years following anterior cruciate ligament reconstruction with or without concomitant meniscal pathology

Purpose

To examine differences in cartilage morphology between young adults 2–3 years post-anterior cruciate ligament reconstruction (ACLR), with or without meniscal pathology, and control participants.

Methods

Knee MRI was performed on 130 participants aged 18–40 years (62 with isolated ACLR, 38 with combined ACLR and meniscal pathology, and 30 healthy controls). Cartilage defects, cartilage volume and bone marrow lesions (BMLs) were assessed from MRI using validated methods.

Results

Cartilage defects were more prevalent in the isolated ACLR (69 %) and combined group (84 %) than in controls (10 %, P < 0.001). Furthermore, the combined group showed higher prevalence of cartilage defects on medial femoral condyle (OR 4.7, 95 % CI 1.3–16.6) and patella (OR 7.8, 95 % CI 1.5–40.7) than the isolated ACLR group. Cartilage volume was lower in both ACLR groups compared with controls (medial tibia, lateral tibia and patella, P < 0.05), whilst prevalence of BMLs was higher on lateral tibia (P < 0.001), with no significant differences between the two ACLR groups for either measure.

Conclusions

Cartilage morphology was worse in ACLR patients compared with healthy controls. ACLR patients with associated meniscal pathology have a higher prevalence of cartilage defects than ACLR patients without meniscal pathology. The findings suggest that concomitant meniscal pathology may lead to a greater risk of future OA than isolated ACLR.

Level of evidence

III.

     

The relationship between patellofemoral and tibiofemoral morphology and gait biomechanics following arthroscopic partial medial meniscectomy

Purpose

To examine the relationship between tibiofemoral and patellofemoral joint articular cartilage and subchondral bone in the medial and gait biomechanics following partial medial meniscectomy.

Methods

For this cross-sectional study, 122 patients aged 30–55 years, without evidence of knee osteoarthritis at arthroscopic partial medial meniscectomy, underwent gait analysis and MRI on the operated knee once for each sub-cohort of 3 months, 2 years, or 4 years post-surgery. Cartilage volume, cartilage defects, and bone size were assessed from the MRI using validated methods. The 1st peak in the knee adduction moment, knee adduction moment impulse, 1st peak in the knee flexion moment, knee extension range of motion, and the heel strike transient from the vertical ground reaction force trace were identified from the gait data.

Results

Increased knee stance phase range of motion was associated with decreased patella cartilage volume (B = ?17.9 (95 % CI ?35.4, ?0.4) p = 0.045) while knee adduction moment impulse was associated with increased medial tibial plateau area (B = 7.7 (95 % CI 0.9, 13.3) p = 0.025). A number of other variables approached significance.

Conclusions

Knee joint biomechanics exhibited by persons who had undergone arthroscopic partial meniscectomy gait may go some way to explaining the morphological degeneration observed at the patellofemoral and tibiofemoral compartments of the knee as patients progress from surgery.

Level of evidence

III.     

Ortner's syndrome: - case series and literature review

More than a century ago, Ortner described a case of cardiovocal syndrome wherein he attributed a case of left vocal fold immobility to compression of the recurrent laryngeal nerve by a dilated left atrium in a patient with mitral valve stenosis. Since then, the term Ortner's syndrome has come to encompass any nonmalignant, cardiac, intrathoracic process that results in embarrassment of either recurrent laryngeal nerve-usually by stretching, pulling, or compression; and causes vocal fold paralysis. Not surprisingly, the left recurrent laryngeal nerve, with its longer course around the aortic arch, is more frequently involved than the right nerve, which passes around the subclavian artery.ObjectivesTo discuss the pathogenesis of hoarseness resulting from cardiovascular disorders involving the recurrent laryngeal nerve along with the findings of literature review.Materials and methodsThis paper reports a series of four cases of Ortner's syndrome occurring due to different causes.DesignCase study.ResultOrtner's syndrome could be a cause of hoarseness of voice in patients with cardiovascular diseases.ConclusionAlthough hoarseness of voice is frequently encountered in the Otolaryngology outpatient department, cardiovascular- related hoarseness is an unusual presentation. Indirect laryngoscopy should be routinely performed in all cases of heart disease.