Medial knee joint loading increases in those who respond to hyaluronan injection for medial knee osteoarthritis

Medial or Lateral, That Is the Question: A Retrospective Study to Compare Two Injection Techniques in the Treatment of Knee Osteoarthritis Pain with Hyaluronic Acid

Background: Mild-to-moderate knee osteoarthritis (KOA) can be successfully treated using intra-articular hyaluronic acid (IA-HA). The medial infrapatellar (MIP) approach and lateral infrapatellar (LIP) approach are two of the most used techniques for performing IA-HA, but it is still not clear which one is preferable. Objectives: The study aims to find the best knee injection technique between MIP and LIP approaches. Methods: In total, 161 patients were enrolled, divided into two groups (MIP or LIP). Each technique was performed once a week for three weeks. Patients were evaluated using the Numeric Rating Scale (NRS), Knee Injury and Osteoarthritis Outcome Score (KOOS) and Roles and Maudsley Score (RMS) at T0 (before the first injection), T1 (one week after the third injection) and T2 (six months after). Results: NRS, KOOS and RMS showed a statistically significant improvement in both groups at all the detection times, without significant differences. No differences were detected between the groups in terms of systemic effect effusions, while the MIP group presented a mildly higher number of bruises in comparison with the LIP group (p = 0.034). Conclusions: Both the IA-HA techniques are equally effective in measured outcomes. The MIP approach seems to produce some local and transient side effects. So, the choice of the LIP or MIP approach depends on the operator's skill and experience.

Baccharis dracunculifolia DC Consumption Improves Nociceptive and Depressive-like Behavior in Rats with Experimental Osteoarthritis

Osteoarthritis (OA) persistently activates nociceptors, leading to chronic pain, which is often accompanied by the comorbid development of emotional impairments (anxiety and depression), an effect associated with microgliosis. Baccharis dracunculifolia DC (Asteraceae), a Brazilian edible plant, is an important source of active compounds with anti-inflammatory abilities. Thus, we evaluated its ability to reverse OA-induced nociceptive and emotional-like impairments in osteoarthritic ovariectomized female rats using the kaolin/carrageenan (K/C) model. Four weeks after OA induction, mechanical hyperalgesia was confirmed, and the treatment started. Control animals (SHAMs) were treated with phosphate-buffered saline (PBS), while arthritic animals (ARTHs) either received PBS or B. dracunculifolia 50 mg/kg (Bd50) and 100 mg/kg (Bd100), via gavage, daily for five weeks. At the end of the treatment, anxiety-like behavior was assessed using the Open Field Test (OFT), anhedonia was assessed using the Sucrose Preference Test (SPT), and learned helplessness was assessed using the Forced Swimming Test (FST). After occision, microglia were stained with IBA-1 and quantified in brain sections of target areas (prefrontal cortex, amygdala, and periaqueductal grey matter). Treatment with B. dracunculifolia extract reversed OA-induced mechanical hyperalgesia and partly improved depressive-like behavior in OA animals' concomitant to a decrease in the number of M1 microglia. Our findings suggest that B. dracunculifolia extracts can potentially be used in the food industry and for the development of nutraceuticals and functional foods.

Relationship Between Knee Biomechanics and Pain in People With Knee Osteoarthritis: A Systematic Review and Meta-Analysis

OBJECTIVE

Our primary aim was to determine the cross-sectional relationship between knee biomechanics during gait and pain in people with medial knee osteoarthritis. Our secondary aim was to evaluate differences in knee biomechanics between symptomatic and asymptomatic participants with medial knee osteoarthritis.

METHODS

Four online databases were searched from inception to July 2021. Eligible studies included people with medial/nonspecific knee osteoarthritis and a reported relationship between knee biomechanics during gait and pain or biomechanics of symptomatic and asymptomatic participants. Two reviewers independently extracted data and evaluated risk of bias. Random-effects meta-analyses were performed when three or more studies reported the same biomechanical variable for pooling (knee adduction moment [KAM], KAM impulse, varus thrust, and peak knee flexion moment [KFM]).

RESULTS

Forty studies were included. Methodological quality ranged from 4 to 9/10. Forty-seven unique biomechanical variables were reported. For the KAM, there was no correlation with pain for peak values pooled (early stance and overall) (r = 0.00, 95% confidence interval [95% CI]: -0.12, 0.11, k = 16), a small negative correlation for early stance peak alone (r = -0.09, 95% CI -0.18, -0.002, k = 12), and a medium positive correlation for the overall peak during stance (r = 0.30, 95% CI 0.17, 0.42, k = 4). Metaregression identified that body mass index moderated the peak KAM-pain relationship (P < 0.001). KAM impulse had a small positive correlation with pain (r = 0.23, 95% CI 0.04, 0.40, k = 5), and people with varus thrust had 3.84 greater odds of reporting pain compared with people without (95% CI 1.72, 8.53, k = 3). Meta-analyses for the peak KFM and pain correlation and secondary aim were nonsignificant.

CONCLUSION

Some knee gait biomechanics were associated with pain in this cohort. Longitudinal studies are required to determine causality.

Intra-articular Injection of Type I Atelocollagen to Alleviate Knee Pain: A Double-Blind, Randomized Controlled Trial

OBJECTIVE

Collagen disruption is one of the underlying causes of knee pain in patients with osteoarthritis and/or diverse cartilage defects. Atelocollagen is a type of collagen that lacks telopeptides and thus has reduced antigenicity. The intra-articular injection of type I atelocollagen supplements collagen levels in the disrupted articular cartilage. This randomized controlled trial evaluated the effects of the intra-articular injection of atelocollagen for the management of knee pain.

DESIGN

Two hundred patients with osteoarthritis, chondromalacia, or other cartilage defects were randomly assigned to receive a 3-mL intra-articular injection of atelocollagen (BioCollagen group) or saline (Placebo group). Clinical improvement was evaluated over a 24-week period using the 100-mm visual analogue scale (VAS), the Western Ontario and McMaster University Osteoarthritis Index (WOMAC), and the 36-item Short-Form Health Survey (SF-36).

RESULTS

VAS scores were significantly better in the BioCollagen group as compared with the Placebo group at 24 weeks. More patients in the BioCollagen group reported exceeding 20% and 40% VAS improvements. The WOMAC and SF-36 scores were also significantly improved from baseline after the intra-articular injection of atelocollagen; although, the differences between the BioCollagen and Placebo groups were not significant. There were no unexpected or severe adverse events reported for either group.

CONCLUSIONS

The results show that an intra-articular injection of atelocollagen effectively alleviates knee pain, as intended. Therefore, the intra-articular injection of atelocollagen can be considered an alternative solution to controlling knee pain due to osteoarthritis and diverse cartilage defects.

Lower limb kinematics improvement after genicular nerve blockade in patients with knee osteoarthritis: a milestone study using inertial sensors

Background

Genicular nerve blockade is a possible treatment for patients with knee osteoarthritis. Pain relief and improvement in functioning is expected. This procedure could be of major interest for patients in low-income countries where total knee arthroplasty is not available for the population. This study aims at assessing the immediate benefits on pain, gait, and stairs kinematics after a genicular nerve blockade in patients suffering from knee osteoarthritis in Cameroun.

Methods

A prospective study was carried out on 26 subjects in Cameroun. A genicular nerve blockade was performed on 14 women with painful knee osteoarthritis grade 2–4. Lower limb joint angles were recorded with inertial sensors before and 1 h after injection. Patient-reported outcomes of pain and perceived difficulty were collected, as well as 10 m and 6 min walking tests. A reliability analysis of inertial sensors was performed on a sample of 12 healthy subjects by calculating the intraclass correlation coefficient and the standard error of measurement.

Results

Pain and perceived difficulty decreased significantly (p < 0.001). Cadence increased significantly in stairs climbing (upstairs: + 7.7 steps/min; downstairs: + 7.6 steps/min). There was an improvement for hip sagittal range of motion during gait (+ 9.3°) and pelvis transverse range of motion in walking upstairs (− 3.3°). Angular speed range of the knee in the sagittal plane and of the hip in the frontal plane increased significantly in stairs descent (+ 53.7°/s, + 94.5°/s).

Conclusions

This study quantified improvement of gait and stair climbing immediately after a genicular nerve blockade in patients suffering from knee OA in Cameroon. This is the first study objectifying this effect, through wearable sensors.

Trial registration

Pan African Clinical Trial Registry, PACTR202004822698484. Registered 28 March 2020 - Retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-020-03836-8.

The wedge insole for the treatment of knee osteoarthritis: A systematic review protocol

BACKGROUND

Functional limitations and pain are common presenting complaints for people suffering from knee osteoarthritis. Wedge insole can be sued for treatment of knee osteoarthritis. Hence, we conducted a systematic review and meta-analysis to explicit the efficacy of wedge insole in the treatment of knee osteoarthritis.

METHODS

A systematic literature search for studies will be performed in MEDLINE, Embase, the Chinese National Knowledge Infrastructure Database (CNKI), Cochrane Library, Web of Science. The methodological quality of the included studies using the risk bias assessment tool of Cochrane. Funnel plot will be used to assess the reporting bias. And the level of evidence for results are assessed by the GRADE method. Statistical analysis is conducted with Revman 5.3.

RESULTS

This systematic review and meta-analysis will provide a synthesis of evidences for wedge insole on knee osteoarthritis.

CONCLUSION

The conclusion of this study will provide recommendations to assess effectiveness of exercise on knee osteoarthritis, which may further guide clinical practice.

PROSPERO REGISTRATION NUMBER

CRD42018096804.

Gait analysis following single-shot hyaluronic acid supplementation: a pilot randomized double-blinded controlled trial

Objectives

Viscosupplementation with new-generation, polyol-containing, cross-linked hyaluronic acid (HA) gels reduces joint inflammation in patients with knee osteoarthritis. Gait analysis is a complementary outcome measure to standard patient-reported scores and physical measures for testing the effect of HA injection. This three-arm, prospective, randomized, controlled, double-blind, feasibility pilot study investigated which gait parameters are more sensitive following a single bolus injection of polyol-containing HA for knee osteoarthritis.

Methods

Twenty-two patients with Ahlbäck grade II-III knee osteoarthritis were randomly allocated into three groups: (1) HA + mannitol (n = 9), (2) HA + sorbitol (n = 5), and (3) saline placebo (n = 8). Patients were assessed by blinded observers prior to injection and at 4 weeks post-injection (4W). Outcome measures included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee Society score (KSS), EuroQol in five-dimensions (EQ-5D), VAS pain, and VAS stiffness. Gait was assessed over 30 m using a portable inertial-based data logger (Physilog®).

Results

Differences between 4W and baseline were statistically significant for the mannitol-containing viscosupplement, with a median increase of 0.076 m/s on gait speed (p = 0.039), 0.055 m on stride length (p = 0.027), and 15 points on the KSS (p = 0.047). In contrast, the HA + sorbitol and saline groups demonstrated no significant changes from baseline to 4W in any gait parameters or self-reported outcome measures (all p > 0.3). The observed increase in gait speed is approximately 13% greater than the mean difference between healthy subjects and those with knee osteoarthritis, is clinically important, and thus is a sensitive gait parameter.

Conclusions

This study demonstrated gait speed and stride length are the most relevant gait parameters to investigate when assessing the effect of polyol-containing HA viscosupplementation. This study supports the need for a larger, randomized, controlled, clinical trial to assess the effect of a single-bolus HA injection versus multiple injections in people with knee osteoarthritis using both gait performance and self-reported parameters of knee function.

Trial registration

This study was retrospectively registered at clinicaltrials.gov on August 20, 2018, and assigned #NCT03636971.

Level of evidence

I.

Is the Wedged Insole an Effective Treatment Option When Compared with a Flat (Placebo) Insole: A Systematic Review and Meta-Analysis

BACKGROUND

Using the lateral wedge insole is a conservative management strategy for knee osteoarthritis. The theoretical basis for this intervention is to correct femorotibial angle, thereby reducing pain and optimising function.

OBJECTIVE

This systematic review evaluates the evidence on the effectiveness of wedge insole compared with flat insole for the treatment of knee osteoarthritis.

METHODS

A systematic review was performed, searching published (MEDLINE, EMBASE, CNKI, Cochrane Library, and Web of Science) and unpublished literature from their inception to April 2018. Randomized controlled trials (RCTs) that compared the use of wedge insole with a flat insole were included. Risk of bias and clinical relevance were assessed, and outcomes were analysed through meta-analysis.

RESULT

From a total of 413 citations, 8 studies adhered to the a priori eligibility criteria. The WOMAC pain was shown to be statistically nonsignificant change with the use of wedge insole (SMD=0.07), and low heterogeneity (I2=22%) and a 95% CI that crossed zero (95% CI: -0.09 to 0.24). The 5 independent trials were not significant in improving pain score (SMD = -0.02, 95% CI: -0.19 to 0.16). This review also revealed no significance in improving Lequesne index (SMD = -0.27, 95% CI: -0.72 to 0.19). The meta-analysis from the 2 independent trials was significant in improving femorotibial angle (SMD = -0.41, 95% CI: -0.73 to -0.09). In conclusion, this meta-analysis suggested that lateral wedge insoles can improve femorotibial angle but are of no benefit with pain and functions in knee osteoarthritis.

Knee Frontal-Plane Biomechanics in Adults With or Without Bone Marrow Edema-Like Lesions After Anterior Cruciate Ligament Injury

CONTEXT

  Lateral subchondral bone bruises (BBs) occur frequently with anterior cruciate ligament (ACL) injuries. These BBs are associated with pain during weight bearing, leading individuals to increase medial tibiofemoral loading to alleviate pain laterally. Increased medial tibiofemoral loading may precipitate the development or progression of posttraumatic osteoarthritis; however, no in vivo biomechanical data exist to confirm that lateral BBs increase medial tibiofemoral loading as measured by the external knee-adduction moment (KAM).

OBJECTIVE

  To determine whether lateral BBs after ACL injury increase the external KAM during walking.

DESIGN

  Descriptive laboratory study.

SETTING

  University research laboratory.

PATIENTS OR OTHER PARTICIPANTS

  Eleven volunteers with an ACL injury (age = 20.36 ± 4.03 years, height = 177.60 ± 8.59 cm, mass = 79.70 ± 16.33 kg), 12 with an ACL injury and a lateral BB (ACL + BB; age = 19.25 ± 5.58 years, height = 170.71 ± 9.40 cm, mass = 66.79 ± 11.91 kg), and 12 healthy controls (age = 19.67 ± 5.19 years, height = 173.29 ± 11.58 cm, mass = 67.07 ± 11.25 kg) participated.

INTERVENTION(S)

  We recorded peak KAM during 3 walking trials (1.1 ± 0.6 m/s) in which participants walked over a force platform located in the field of view of a motion-capture system.

MAIN OUTCOME MEASURE(S)

  Peak KAM was calculated during the first half of stance using standard inverse-dynamics analysis, averaged across trials, and examined via 1-way analysis of variance. Knee pain and function were determined from the International Knee Documentation Committee Subjective Knee Evaluation Form and compared among groups via the Kruskal-Wallis test.

RESULTS

  Peak KAM did not differ among groups (ACL injury = 0.14 ± 0.07 Nm·kg^-1·m^-1, ACL + BB = 0.21 ± 0.08 Nm·kg^-1·m^-1, control = 0.20 ± 0.08 Nm·kg^-1·m^-1; F_2,35 = 3.243, P = .052). Knee-pain frequency and severity were greater in the ACL-injury (frequency = 2.55 ± 1.81, severity = 3.36 ± 1.75; both P < .001) and ACL + BB (frequency = 3.58 ± 2.81, severity = 4.08 ± 3.20; both P < .001) groups than in the control group (frequency = 0.00 ± 0.00, severity = 0.00 ± 0.00). Knee function was greater in the control group (100.00 ± 0.00) than in the ACL-injury (59.35 ± 17.31; P < .001) and ACL + BB (46.46 ± 25.85; P < .001) groups.

CONCLUSIONS

  The ACL + BB groups did not walk with a greater external KAM than the ACL-injury or control groups. Thus, lateral tibiofemoral BB did not influence knee frontal-plane loading after ACL injury.

The effect of instruction in analgesic use compared with neuromuscular exercise on knee-joint load in patients with knee osteoarthritis: a randomized, single-blind, controlled trial

OBJECTIVE

To investigate the effect of a neuro-muscular exercise (NEMEX) therapy program compared with instructions in optimized analgesics and anti-inflammatory drug use (PHARMA), on measures of knee-joint load in people with mild to moderate knee osteoarthritis (OA). We hypothesized that knee joint loading during walking would be reduced by NEMEX and potentially increased by PHARMA.

DESIGN

Single-blind, randomized controlled trial (RCT) comparing NEMEX therapy twice a week with PHARMA. Participants with mild-to-moderate medial tibiofemoral knee OA were randomly allocated (1:1) to one of two 8-week treatments. Primary outcome was change in knee load during walking (Knee Index, a composite score from all three planes based on 3D movement analysis) after 8 weeks of intervention. Secondary outcomes were frontal plane peak knee adduction moment (KAM), Knee Injury and Osteoarthritis Outcome Scores (KOOS) and functional performance tests.

RESULTS

Ninety three participants (57% women, 58 ± 8 years with a body mass index [BMI] of 27 ± 4 kg/m² (mean ± standard deviation [SD])) were randomized to NEMEX group (n = 47) or PHARMA (n = 46); data from 44 (94%) and 41 (89%) participants respectively, were available at follow-up. 49% of the participants in NEMEX and only 7% in PHARMA demonstrated good compliance. We found no difference in the primary outcome as evaluated by the Knee Index -0.07 [-0.17; 0.04] Nm/%BW HT. Secondary outcomes largely supported this finding.

CONCLUSIONS

We found no difference in the primary outcome; knee joint load change during walking from a NEMEX program vs information on the recommended use of analgesics and anti-inflammatory drugs. ClinicalTrials.gov Identifier: NCT01638962 (July 3, 2012). Ethical Committee: S-20110153.

Wedged Insoles and Gait in Patients with Knee Osteoarthritis: A Biomechanical Review

The study of gait biomechanics in individuals with knee osteoarthritis has become widespread, especially in regards to the knee adduction moment-a variable commonly believed to be associated with knee osteoarthritis progression. Unfortunately, this variable is often studied clinically without considering how it is derived, or what it means in a mechanical context. The use of footwear for knee osteoarthritis management has received much attention as well. However, in many cases, footwear is studied without regard for the mechanical effects they actually induce on the patient. Therefore, this review aims to summarize the current state of knowledge in regards to knee osteoarthritis gait and footwear biomechanics, by taking a step back to review the foundations of these two research areas. First, an overview of the calculation of the knee adduction moment is provided, along with mechanical considerations. Then, this is used to discuss current evidence for wedged insoles and highlight knowledge gaps. The intent was to place this mechanical information in a clinically-oriented framework for approachability by scientists, engineers and clinicians alike. Based on this discussion, areas for future investigation are proposed.

Effectiveness of intra-articular injections of sodium bicarbonate and calcium gluconate in the treatment of osteoarthritis of the knee: a randomized double-blind clinical trial

Background

A novel therapeutic management of osteoarthritis (OA) of the knee was assessed. The study aimed to evaluate the effect of monthly sodium bicarbonate with a single (SBCG1) or double dose (SBCG2) of calcium gluconate injections on OA of the knee; as well as the efficacy and safety of both SBCG interventions in the long term.

Methods

A double-blind parallel-group clinical trial with 74 knee OA patients was performed during 12 months, both SBCG interventions were followed-up for another 6mo after intervention. The outcome variables were the Western Ontario-McMaster University Osteoarthritis Index (WOMAC), the Lequesne’s functional index and joint-space width changes from serial radiographs.

Results

After 12 months, group SBCG1 decreased −14.8 (95% CI:-14.2, −17.0) and group SBCG2 decreased −14.6 (−16.9, −12.4) in the global WOMAC score, the mean changes represent 80% and 82% lessened pain, respectively. In the Lequesne Functional Index scale, SBCG1 decreased −11.9 (−10.4, −14.2) and SBCG2 decreased -11.9 (−13.8, −10.0), representing 66 and 69% of improvement. Both mean scores were maintained after intervention discontinued. SBCG2 improved the knees’ joint space width more than SBCG1 at 3 and 18 months. Both SBCG interventions were well tolerated after 12 months of treatment

Conclusion

A solution of sodium bicarbonate and calcium gluconate is effective on reducing the symptoms associated with OA. Its beneficial effect is maintained for one year of continuous monthly administration and at least for 6 months after the administration is discontinued. When the dose of calcium gluconate is increased, it prevents further narrowing of joint-space.

Trial registration

Clinicaltrials.gov NCT00977444 September 11, 2009.

Asymmetries and relationships between dynamic loading, muscle strength, and proprioceptive acuity at the knees in symptomatic unilateral hip osteoarthritis

Introduction

High joint loading, knee muscle weakness, and poor proprioceptive acuity are important factors that have been linked to knee osteoarthritis (OA). We previously reported that those with unilateral hip OA and bilateral asymptomatic knees are more predisposed to develop progressive OA in the contralateral knee relative to the ipsilateral knee. In the present study, we evaluate asymmetries in muscle strength and proprioception between the limbs and also evaluate relationships between these factors and joint loading that may be associated with the asymmetric evolution of OA in this group.

Methods

Sixty-two participants with symptomatic unilateral hip OA and asymptomatic knees were evaluated for muscle strength, joint position sense and dynamic joint loads at the knees. Muscle strength and proprioception were compared between limbs and correlations between these factors and dynamic joint loading were evaluated. Subgroup analyses were also performed in only those participants that fulfilled criteria for severe hip OA.

Results

Quadriceps muscle strength was 15% greater, and in the severe subgroup, proprioceptive acuity was 25% worse at the contralateral compared to ipsilateral knee of participants with unilateral hip OA (P <0.05). In addition, at the affected limb, there was an association between decreased proprioceptive acuity and higher knee loading (Spearman’s rho = 0.377, P = 0.007) and between decreased proprioceptive acuity and decreased muscle strength (Spearman’s rho = −0.328, P = 0.016).

Conclusions

This study demonstrated asymmetries in muscle strength and proprioception between the limbs in a unilateral hip OA population. Early alterations in these factors suggest their possible role in the future development of OA at the contralateral ‘OA-predisposed knee’ in this group. Furthermore, the significant association observed between proprioception, loading, and muscle strength at the affected hip limb suggests that these factors may be interrelated.

The effect on knee-joint load of instruction in analgesic use compared with neuromuscular exercise in patients with knee osteoarthritis: study protocol for a randomized, single-blind, controlled trial (the EXERPHARMA trial)

BACKGROUND

Knee osteoarthritis (OA) is a mechanically driven disease, and it is suggested that medial tibiofemoral knee-joint load increases with pharmacologic pain relief, indicating that pharmacologic pain relief may be positively associated with disease progression. Treatment modalities that can both relieve pain and reduce knee-joint load would be preferable. The knee-joint load is influenced by functional alignment of the trunk, pelvis, and lower-limb segments with respect to the knee, as well as the ground-reaction force generated during movement. Neuromuscular exercise can influence knee load and decrease knee pain. It includes exercises to improve balance, muscle activation, functional alignment, and functional knee stability. The primary objective of this randomized controlled trial (RCT) is to investigate the efficacy of a NEuroMuscular EXercise (NEMEX) therapy program, compared with optimized analgesics and antiinflammatory drug use, on the measures of knee-joint load in people with mild to moderate medial tibiofemoral knee osteoarthritis.

METHOD/DESIGN

One hundred men and women with mild to moderate medial knee osteoarthritis will be recruited from general medical practices and randomly allocated (1:1) to one of two 8-week treatments, either (a) NEMEX therapy twice a week or (b) information on the recommended use of analgesics and antiinflammatory drugs (acetaminophen and oral NSAIDs) via a pamphlet and video materials. The primary outcome is change in knee load during walking (the Knee Index, a composite score of the first external peak total reaction moment on the knee joint from all three planes based on 3D movement analysis) after 8 weeks of intervention. Secondary outcomes include changes in the external peak knee-adduction moment and impulse and functional performance measures, in addition to changes in self-reported pain, function, health status, and quality of life.

DISCUSSION

These findings will help determine whether 8 weeks of neuromuscular exercise is superior to optimized use of analgesics and antiinflammatory drugs regarding knee-joint load, pain and physical function in people with mild to moderate knee osteoarthritis.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01638962 (July 3, 2012).

Potential interaction of experimental knee pain and laterally wedged insoles for knee off-loading during walking

BACKGROUND

Laterally wedged insoles are one of the gait modifications potentially slowing down progression of medial knee osteoarthritis. Clinical studies have, however, found large individual differences in the biomechanical effect and an insufficient pain reduction. To clarify if and how pain mediates mechanical changes during gait the current study investigated how acute experimental knee pain changes the mechanical effect of laterally wedged insoles in healthy subjects during walking.

METHODS

3D gait analysis was carried out for twelve healthy individuals. The study followed a cross-over design and data were collected with both a neutral and a 10-degree laterally wedged insole with experimental pain induced by hypertonic and isotonic saline injections into the infrapatellar fat pad. Peak knee adduction moment was the primary outcome. A repeated ANOVA (analysis of variance) was used to evaluate the relationship between the factors wedge, condition and test number.

FINDINGS

Wedges significantly reduced peak knee adduction moment but experimental knee pain did only marginally affect its magnitude in either condition. While frontal plane mechanics were relatively unaffected by pain, the sagittal plane knee extension moment increased with laterally wedging (P=0.008), whereas late knee flexion moment was reduced by experimental knee pain (P=0.04).

INTERPRETATION

The effect of laterally wedged insoles in attenuating knee adduction moment during walking is independent of experimental knee pain. The present study provides evidence that subjects with experimental knee pain reduce knee loading by reducing extension moment, whereas lateral wedges have the opposite effect and increase the extension moment.

Early knee osteoarthritis management should first address mechanical joint overload

Early knee osteoarthritis poses a therapeutic dilemma to the musculoskeletal clinician. Despite the recent interest in arthroscopic and injectable regenerative therapies intended to repair or restore a focal target such as cartilage, meniscus, or subchondral bone, none have been shown to slow disease progression. A likely cause of these disappointing treatment outcomes is the failure to address chronic and excessive loading of the knee joint. A growing body of evidence suggests that first-line therapies for early knee osteoarthritis should emphasize unloading the knee joint since any potential therapeutic benefit of regenerative therapies will likely be attenuated by excessive mechanical demand at the knee joint. Minimally invasive medical devices such as patient-specific interpositional implants and extracapsular joint unloading implants are currently in development to address this clinical need.

Quality of life in patients with knee osteoarthritis: a commentary on nonsurgical and surgical treatments

Knee osteoarthritis (OA) has a significant negative impact on health-related quality of life (HRQoL). Identification of therapies that improve HRQoL in patients with knee OA may mitigate the clinical, economic, and social burden of this disease. The purpose of this commentary is to report the impact of knee OA on HRQoL, describe the change in HRQoL attributable to common knee OA interventions, and summarize findings from clinical trials of a promising therapy. Nonsurgical therapies do not reliably modify HRQoL in knee OA patients given their general inability to alleviate physical manifestations of OA. Surgical knee OA interventions generally result in good to excellent patient outcomes. However, there are significant barriers to considering surgery, which limits clinical utility. Therapies that most effectively control OA-related pain with a low risk: benefit ratio will likely have the greatest benefit on HRQoL with greater rates of patient adoption. Initial clinical trial findings suggest that less invasive joint unloading implants hold promise in bridging the therapeutic gap between nonsurgical and surgical treatments for the knee OA patient.

The KineSpring(®) Knee Implant System: an implantable joint-unloading prosthesis for treatment of medial knee osteoarthritis

Symptomatic medial compartment knee osteoarthritis (OA) is the leading cause of musculoskeletal pain and disability in adults. Therapies intended to unload the medial knee compartment have yielded unsatisfactory results due to low patient compliance with conservative treatments and high complication rates with surgical options. There is no widely available joint-unloading treatment for medial knee OA that offers clinically important symptom alleviation, low complication risk, and high patient acceptance. The KineSpring^® Knee Implant System (Moximed, Inc, Hayward, CA, USA) is a first-of-its-kind, implantable, extra-articular, extra-capsular prosthesis intended to alleviate knee OA-related symptoms by reducing medial knee compartment loading while overcoming the limitations of traditional joint-unloading therapies. Preclinical and clinical studies have demonstrated excellent prosthesis durability, substantial reductions in medial compartment and total joint loads, and clinically important improvements in OA-related pain and function. The purpose of this report is to describe the KineSpring System, including implant characteristics, principles of operation, indications for use, patient selection criteria, surgical technique, postoperative care, preclinical testing, and clinical experience. The KineSpring System has potential to bridge the gap between ineffective conservative treatments and irreversible surgical interventions for medial compartment knee OA.

Midterm Outcomes and Predictors of Clinical Success With the KineSpring Knee Implant System

The purpose of this study was to (1) evaluate joint pain and function in knee osteoarthritis (OA) patients treated with a joint-sparing, extracapsular implant and (2) identify patient characteristics that influenced clinical outcomes. This study included 99 patients with symptomatic medial knee OA refractory to conservative care who were treated with the KineSpring Knee Implant System and followed for a mean of 17 months (range, 1.5 to 48 months). All devices were successfully implanted and activated with no intraoperative complications. Statistically significant mean improvements of 56%, 50%, and 38% were observed for Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain, Function, and Stiffness scales, respectively (all P < 0.001). Regardless of gender, age group, body mass index classification, or disease severity, all WOMAC domain scores significantly improved during the postoperative follow-up period. WOMAC clinical success rates were 77.8% for Pain, 77.8% for Function, and 68.7% for Stiffness. Neither gender, age group, body mass index classification, nor disease severity predicted clinical success in any WOMAC domain. In conclusion, the KineSpring System yields clinically meaningful improvements in joint pain and function in patients with medial knee OA. Additionally, unlike joint-altering procedures such as knee arthroplasty or high tibial osteotomy, patient characteristics had little association with postoperative clinical outcomes.

Gait deviations in individuals with inflammatory joint diseases and osteoarthritis and the usage of three-dimensional gait analysis

This chapter describes three-dimensional gait analysis and common gait deviations in adults with rheumatoid arthritis (RA) and osteoarthritis (OA). Furthermore, we describe changes in gait deviations following surgical and non-surgical interventions. Gait analysis is used to define gait deviations and to evaluate varying surgical approaches, types of surgeries and non-pharmacologic interventions. Most studies examine gait in adults with knee OA. Limitations of existing studies include small samples, poor selection of controls, sample heterogenecity, lack of baseline gait assessments and inconsistency in measurement. Across studies, time and distance parameters are generally used to provide a global measure of gait deviations. Individuals with RA and OA in the lower extremities exhibit reduced walking speed/cadence and decreased motion and moments in relation to healthy subjects. Future research should include larger sample sizes, the use of proper controls, pre- and post-assessments and identify gait abnormalities early in the disease process to minimise long-term consequences.

Conservative management of symptomatic knee osteoarthritis: a flawed strategy?

Conservative management of medial compartment knee osteoarthritis (OA) is a misleading term used to describe the application of medical, orthotic, and/or rehabilitative therapies exclusive of surgical interventions. The implication of this nomenclature is that these therapies offer satisfactory symptom relief, alter disease progression, and have limited side effects. Unfortunately, conservative therapeutic options possesses few, if any, characteristics of an ideal treatment, namely one that significantly alleviates pain, improves knee function, and reduces medial compartmental loading without adverse side effects. As uncompensated mechanical loading is a primary culprit in the development and progression of knee OA, we propose that the therapeutic perspective of conservative treatment should shift from pharmacological treatments, which have no influence on joint loading, minimal potential to alter joint function, substantial associated risks, and significant financial costs, towards minimally invasive load absorbing therapeutic interventions. A safe and effective minimally invasive medical device specifically engineered for symptomatic relief of medial knee OA by limiting joint contact forces has the potential to reduce the clinical and economic knee OA burden. This review characterizes the current standard of care recommendations for conservative management of medial compartment knee OA with respect to treatment efficacy, risk profile, and economic burden.

Is there a dose response for valgus unloader brace usage on knee pain, function, and muscle strength?

OBJECTIVE

To examine whether there was a dose response for valgus unloader brace wear on knee pain, function, and muscle strength in participants with medial compartment knee osteoarthritis.

DESIGN

In this single-group study, participants with medial compartment knee osteoarthritis were followed for approximately 6 months.

SETTING

Recruitment was conducted in the general community, and testing was performed at a university laboratory.

PARTICIPANTS

A convenience sample of patients (N=32) who were prescribed a valgus unloader brace agreed to participate, met the inclusion criteria, and completed the baseline data collection. Twenty-four participants (20 men, 4 women) completed baseline and follow-up collections.

INTERVENTION

Participants wore their valgus unloader brace as needed.

MAIN OUTCOME MEASURES

Knee extensor, flexor, and plantar flexor strength was tested at baseline and follow-up. Participants filled out Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Medical Outcomes Study 36-Item Short-Form Health Survey questionnaires to assess pain and function. Self-selected walking velocity and stride length were objective measures of function. Brace usage (dose) and activity (step count) were recorded at least 4 days/week for the study duration.

RESULTS

Positive relationships existed between brace wear usage and percent change in step count (r=.59, P=.006) and percent change in hamstrings strength (r=.37, P=.072). At follow-up, there was significant improvement in hamstrings strength (P=.013), and trends toward improvements in WOMAC pain (P=.059) and WOMAC function (P=.089).

CONCLUSIONS

Our results indicate that greater brace use may positively affect physical activity level, but there was minimal effect of brace wear dosage on lower-limb muscle strength. Only knee flexion showed a positive relationship. Our finding of no decreased muscle strength indicates that increased brace use over a 6-month period does not result in muscle impairment.

Lateral wedge insoles for medial knee osteoarthritis: 12 month randomised controlled trial

OBJECTIVE

To assess the effect of lateral wedge insoles compared with flat control insoles on improving symptoms and slowing structural disease progression in medial knee osteoarthritis.

DESIGN

Randomised controlled trial.

SETTING

Community in Melbourne, Australia.

PARTICIPANTS

200 people aged 50 or more with clinical and radiographic diagnosis of mild to moderately severe medial knee osteoarthritis.

INTERVENTIONS

Full length 5 degree lateral wedged insoles or flat control insoles worn inside the shoes daily for 12 months.

MAIN OUTCOME MEASURES

Primary symptomatic outcome was change in overall knee pain (past week) measured on an 11 point numerical rating scale. Primary structural outcome was change in volume of medial tibial cartilage from magnetic resonance imaging scans. Secondary clinical outcomes included changes in measures of pain, function, stiffness, and health related quality of life. Secondary structural outcomes included progression of medial cartilage defects and bone marrow lesions.

RESULTS

Between group differences did not differ significantly for the primary outcomes of change in overall pain (-0.3 points, 95% confidence intervals -1.0 to 0.3) and change in medial tibial cartilage volume (-0.4 mm(3), 95% confidence interval -15.4 to 14.6), and confidence intervals did not include minimal clinically important differences. None of the changes in secondary outcomes showed differences between groups.

CONCLUSION

Lateral wedge insoles worn for 12 months provided no symptomatic or structural benefits compared with flat control insoles. Trial registration Australian New Zealand Clinical Trials Registry ACTR12605000503628 and ClinicalTrials.gov NCT00415259.

The KineSpring load absorber implant: rationale, design and biomechanical characterization

Osteoarthritis (OA) of the knee is the leading cause of disability in the adult population. Although a number of treatments for knee OA are available, none effectively prevent OA progression. Currently, a wide therapeutic gap exists for patients who have unsuccessfully exhausted conservative OA treatments but who are hesitant or ineligible to undergo invasive surgery. The KineSpring device is a novel, joint preserving, minimally invasive implant that reduces medial compartment loading without significantly impacting the loading of the lateral compartment. This article describes the rationale for and the design of the KineSpring device and summarizes results of initial biomechanical testing in an OA cadaver model.

Clinical and economic consequences of the treatment gap in knee osteoarthritis management

Osteoarthritis affects 27 million American adults of all ages and is a leading cause of disability in middle-aged and older adults. Initial management of knee osteoarthritis symptoms utilizes conservative care although long-term efficacy is poor. Arthroplasty and high tibial osteotomy may be considered for patients with severe pain or disability. We hypothesize that a distinct treatment gap exists for the patient with symptomatic knee osteoarthritis who is unresponsive to conservative care (including simple surgical treatments) yet refuses to undergo or is not an appropriate candidate for more invasive surgical procedures. This treatment gap represents a protracted period in which the patient experiences debilitating pain, reduced quality of life, and a significant financial burden. Approximately 3.6 million Americans linger in the knee osteoarthritis treatment gap and this number will grow to about 5 million people by 2025. The typical knee osteoarthritis treatment gap extends 20 years although the younger osteoarthritis patient is faced with the treatment gap throughout the majority of their adult life. There is great need for a safe, effective, and cost effective treatment option for patients with moderate to severe osteoarthritis that enjoys high patient acceptance.

Gait analysis of knee arthritis treated with hyaluronic acid

Self-reported studies have demonstrated efficacy of hyaluronic acid (HA) therapy. Gait analysis may objectively demonstrate changes associated with HA therapy. Fifty-three consecutive patients with unilateral osteoarthritis (OA) of the knee were evaluated with a validated and sensitive gait laboratory previously used for gonarthrosis. Two 100-meter walks were performed before and after HA therapy. Nineteen parameters were measured. In addition, the subjective response to treatment was correlated with changes in gait parameters. Single-limb support time, velocity, fatigability, and swing phase were not improved. Only double-limb support time was found to be significantly different (P = .04). The remaining gait variables were not changed. Separately, the subset of patients that achieved greater than 70% subjective pain relief had no objective improvements in gait parameters. Hyaluronic acid therapy may result in a placebo effect for the treatment of gonarthrosis.