BACKGROUND: Knee pain is a major cause of disability worldwide, particularly among the elderly. Current treatments, including nonsteroidal anti-inflammatory drugs and analgesics, often lead to adverse effects. Krill oil is being explored as a potential alternative, however its efficacy in managing knee symptoms remains unclear.
METHODS: MEDLINE, Embase, and Cochrane databases were searched until May 2024 for studies comparing krill oil and placebo in knee pain patients. Endpoints included knee pain, stiffness, physical function, and lipid profiles (HDL-C, LDL-C, triglycerides, and total cholesterol). A restricted maximum likelihood random-effects model with standardized mean differences (SMD) and 95% confidence intervals (CI) was used. A trial sequential analysis was conducted to evaluate further research implications.
RESULTS: We included five trials with 700 patients using krill oil for knee pain. Results showed no significant difference between krill oil and placebo for knee pain, knee stiffness, and lipid profiles. However, krill oil demonstrated a significant small effect in improving knee physical function (SMD -0.24, 95% CI [-0.41; -0.08], I2 = 0%).Trial sequential analysis provided certainty that krill oil enhances knee physical function compared to placebo and indicated no improvement in knee pain, but the findings for knee stiffness need to be confirmed by further research.
CONCLUSIONS: This study found that krill oil supplementation did not significantly improve knee pain, stiffness, or lipid profile, although it may help knee physical function. Based on these findings, krill oil supplementation is not yet justified for knee pain.

Knee osteoarthritis (OA) affects millions worldwide, leading to pain and reduced quality of life. Conventional treatments often fail to provide adequate relief, necessitating new therapeutic approaches. This study evaluated the efficacy and safety of genicular artery embolization (GAE) using permanent microspheres in patients with mild-to-moderate knee OA. In this prospective, single-center study, 17 participants underwent GAE. KOOS (Knee injury and Osteoarthritis Outcome Score), WOMAC (The Western Ontario and McMaster Universities Arthritis Index), and IPAQ (International Physical Activity Questionnaire) scores, along with physical performance tests, medication use, and dual-energy X-ray absorptiometry (DEXA) scans, were assessed at baseline and at multiple follow-up points over six months. The primary endpoint, VAS at six months, showed significant improvement (median reduction from 66 mm to 40 mm, p = 0.0004). All pain and function scores, as well as physical performance tests, improved significantly. No clinically relevant changes in medication use or DEXA parameters were observed after six months. Only minor, self-limiting adverse events occurred. This study indicates that GAE is a promising minimally invasive treatment for knee OA, providing significant pain relief and functional improvement. However, further long-term, randomized trials are needed to confirm these findings and establish optimal patient selection criteria.

UNASSIGNED: The reported incidence of posttraumatic knee osteoarthritis (PTOA) after primary anterior cruciate ligament reconstruction (ACLR) varies considerably. Further, there are gaps in identifying which patients are at risk for PTOA after ACLR and whether there are modifiable factors.
UNASSIGNED: To (1) determine the incidence of PTOA in a primary ACLR cohort and (2) identify patient and perioperative factors associated with the development of PTOA after primary ACLR.
UNASSIGNED: Cohort study; Level of evidence, 3.
UNASSIGNED: Data from the Kaiser Permanente ACLR Registry were used to conduct a cohort study. Patients who had undergone primary ACLR without a previous diagnosis of osteoarthritis were identified (2009-2020). The crude incidence of PTOA was calculated using the Aalen-Johansen estimator with a multistate model. The association of patient and operative factors with the development of PTOA after primary ACLR was modeled as a time to event using multistate Cox proportional hazards regression. Models stratified by age (<22 and ≥22 years) were also conducted because of the effect modification of age.
UNASSIGNED: The study sample included 41,976 cases of primary ACLR. The incidence of PTOA was 1.7%, 5.1%, and 13.6% at 2, 5, and 10 year follow-ups, respectively. Risk factors for PTOA that were consistently identified in the overall cohort and age-stratified groups included a body mass index ≥30 versus <30 and an allograft or quadriceps tendon autograft versus a hamstring tendon autograft. Patients presenting with knee pain after ACLR were further identified when considering postoperative factors. Other risk factors for PTOA in the overall cohort included age ≥22 versus <22 years, bone-patellar tendon-bone autograft versus hamstring tendon autograft, hypertension, cartilage injury, meniscal injury, revision after primary ACLR with concomitant meniscal/cartilage surgery, multiligament injury, other activity at the time of injury compared with sport, and tibial tunnel drilling technique rather than the anteromedial portal.
UNASSIGNED: Knee pain after ACLR may be an early sign of PTOA. Surgeons should consider the adverse associations of a higher body mass index and an allograft or quadriceps tendon autograft with the development of PTOA, as these were factors identified with a higher risk, regardless of a patient\'s age at the time of primary ACLR.

UNASSIGNED: Negative psychological beliefs like fear avoidance and catastrophizing can interfere with exercise engagement in people with knee osteoarthritis (OA). Mindfulness, when integrated with exercise, could potentially address both psychological and physical impairments. Our objectives were to optimize and assess the feasibility of a novel telehealth, group-based mindful exercise intervention for people with knee OA.
UNASSIGNED: We conducted a decentralized randomized controlled trial where participants (n ​= ​40) with symptomatic knee OA were randomized into mindful exercise (n ​= ​21) or exercise-only (n ​= ​19) groups. Both groups received supervised group-based interventions weekly for 8-weeks via Zoom. Primary outcomes were safety, fidelity, and feasibility of the mindful exercise intervention. Participants completed patient-reported outcomes (PRO) for pain, function, and psychological measures at baseline, week-8, and week-14.
UNASSIGNED: Participants were from 21 US states; >90% identified as having White race, 16% were from rural areas, and approximately 40% had an annual income < $50,000. At 8-weeks, mindful exercise and exercise groups had retention rates of 86% (18/21) and 100% (19/19), and attendance was 54% (11.4/21) and 68% (13/19) respectively. There were no adverse events in the mindful exercise group and four in the exercise group related to exacerbation of knee pain. Preliminary findings showed numerically larger improvements in several PROs for the mindful exercise group.
UNASSIGNED: An 8-week telehealth, group-based, mindful exercise intervention was safe for people with knee OA. Our decentralized approach was feasible in terms of recruitment and retention. Further refinement is needed to improve intervention attendance and participant diversity.

UNASSIGNED: Various pathophysiological contexts can be accompanied by weakness, arthrogenic muscle inhibition, and even disability. In this scenario, peripheral nerve stimulation has been studied not only for pain management but also for the improvement of neuromuscular parameters. For this purpose, the use of Transcutaneous Electrical Nerve Stimulation (TENS) has typically been investigated, but recently, the use of ultrasound-guided percutaneous peripheral nerve stimulation (pPNS) has gained popularity. In this regard, electrical stimulation has a predisposition to activate Type II muscle fibers and has been shown to be capable of generating short-term potentiation by increasing calcium sensitivity. However, the evidence of pPNS applied in humans investigating such variables is rather limited.
UNASSIGNED: This pilot study aimed to assess the feasibility of the methodology and explore the potential of pPNS in enhancing hip extension performance in individuals suffering from knee pain, comparing it with TENS.
UNASSIGNED: Twelve participants were divided into pPNS and TENS groups, undergoing pre- and post-intervention assessments of peak concentric power (W), strength (N), execution speed (m/s), and one-repetition maximum (1RM) (kg) estimation. For pPNS, two needles were positioned adjacent to the superior and inferior gluteal nerves under ultrasound guidance. For TENS, electrodes were positioned between the posterosuperior iliac spine and the ischial tuberosity, and halfway between the posterosuperior iliac spine and the greater trochanter. The interventions consisted of 10 stimulations of 10 s at a frequency of 10 Hz with a pulse width of 240 μs, with rest intervals of 10 s between stimulations.
UNASSIGNED: Peripheral nerve stimulation significantly improved concentric power at 30% (p = 0.03) and 50% (p = 0.03) of 1RM, surpassing TENS, which showed minimal changes. No significant strength differences were observed post-intervention in either group.
UNASSIGNED: This work presents evidence where pPNS applied to the gluteal nerves results in an enhanced performance of hip extension at submaximal loads. However, this improvement does not seem to be reflected in short-term changes in the estimation of the 1RM by the force-velocity profile.

UNASSIGNED: The relationship between psychosocial factors and bodily pain in people with knee osteoarthritis (KOA) is unclear.
UNASSIGNED: To examine whether widespread pain was associated with poorer self-efficacy, more anxiety, depression, and kinesiophobia in people with KOA.
UNASSIGNED: This was a cross-sectional study based on data from Good Life with osteoArthritis in Denmark (GLA:D®). The association between widespread pain (multiple pain sites) and self-efficacy (Arthritis Self-Efficacy Scale), anxiety and depression (item from the EQ-5D-5 L), and kinesiophobia (yes/no) was examined using multiple linear tobit or logistic regression models.
UNASSIGNED: Among 19,323 participants, 10% had no widespread pain, 37% had 2 pain sites, 26% had 3-4 pain sites, and 27% had ≥5 pain sites. Widespread pain was associated with poorer self-efficacy (-0.9 to -8.3 points), and the association was stronger with increasing number of pain sites (p-value <.001). Significant increasing odds ratios (ORs) were observed for having anxiety or depression with 3-4 pain sites (OR 1.29, 95% CI 1.12; 1.49) and ≥5 pain sites (OR 1.80, 95% CI 1.56; 2.07). Having 2 and 3-4 pain sites were associated with lower odds of kinesiophobia compared to having no widespread pain.
UNASSIGNED: Widespread pain was associated with lower self-efficacy and more anxiety and depression but also lower kinesiophobia in people with KOA.

OBJECTIVE: Knee pain, specifically patellofemoral pain (PFP), may lead to limitations in physical activity and social participation. Identifying knee pain that is attributed to PFP is not an easy job for healthcare professionals. To overcome this issue, The Survey Instrument for Natural History, Aetiology and Prevalence of Patellofemoral Pain (SNAPPS), which is a self-reporting questionnaire instrument, was designed to identify PFP in many languages. However, the Arabic version of the SNAPPS is not validated yet. This study was performed to assess the validity and reliability of the Arabic version of the SNAPPS (A-SNAPPS).
METHODS: A cross-sectional study was conducted to achieve the study goals. To assess reliability, 38 participants were asked to complete the A-SNAPPS two times on the same day with a 30 min break in between. Convergent validity of the A-SNAPPS was assessed by exploring the correlations of the SNAPPS total score with the visual analogue scale (VAS) scores, including VAS for usual pain, VAS for worst pain, and VAS for pain during activities such as jumping, running, ascending and descending stairs, and squatting.
RESULTS: The validity test findings suggested that SNAPPS has a strong correlation with the VAS during ascending and descending stairs (r = 0.71) and moderate correlations during jumping (r = 0.54) and squatting (r = 0.57). The test-retest reliability ICC was 0.92, indicating a very strong test-retest reliability of the A-SNAPPS.
CONCLUSIONS: The A-SNAPPS was cross-culturally adapted and validated, demonstrating very strong reliability.

OBJECTIVE: To investigate the impact of genicular artery embolization (GAE) on synovitis in knee osteoarthritis (OA) using contrast-enhanced magnetic resonance (MR) imaging, and to assess its predictive role in pain response.
METHODS: A single-center retrospective analysis was conducted using contrast-enhanced MR imaging on 33 patients treated with GAE for knee OA between December 2022 and March 2023. MR assessments before the procedure and at 3-months after embolization were utilized in a semiquantitative scoring system for synovitis severity and distribution analysis. Pain and function through Western Ontario and McMaster Universities Osteoarthritis Index and visual analog scale scores were also assessed.
RESULTS: Significant synovitis reduction was noted after GAE, particularly in parapatellar and periligamentous areas. Synovial contrast enhancement scores significantly decreased from 5.1 (SD ± 2.0) to 2.9 (SD ± 2.0) at 3 months (P < .001), with a moderate negative correlation between synovial enhancement scores and pain levels (P = .005).
CONCLUSIONS: GAE significantly reduced synovitis in knee OA, evidenced by contrast-enhanced MR imaging. The correlation between preprocedural synovial contrast enhancement scores and pain relief after the procedure, although promising, requires careful interpretation because of the complex factors affecting pain in knee OA.

Background: Knee osteoarthritis is the most prevalent type of osteoarthritis. Patients frequently encounter pain triggered by movement that evolves into impaired joint function. Needing persistent rest or having night-time pain signifies advanced disease. Qualitative research is considered the most effective method for comprehending patients\' needs and contexts. Methods: This study employed a qualitative research design, allowing the researchers to acquire insights into the patients\' beliefs and values, and the contextual factors influencing the formation and expression of these beliefs and values. Results: A cohort of nine patients awaiting total knee replacement (TKR) surgery was included and they were interviewed until data saturation was achieved. The results of the phenomenological analysis resulted in the identification of three themes: \"The existence of pain impedes the capacity to participate in daily life activities\"; \"TKR induced fears and uncertainties regarding the progression of the disease\"; \"Severe nighttime pain compromising sleep quality\". Conclusions: This study analyzes the experiences of people awaiting TKR surgery, emphasizing the importance of addressing their unique needs to improve preoperative education and rehabilitation. In this way, patients\' recovery during the postoperative phase can be improved.

BACKGROUND: This retrospective medium-term follow-up study compares the outcomes of medial fixed-bearing unicompartmental knee arthroplasty (mUKA) using a cemented metal-backed (MB) or an all-polyethylene (AP) tibial component.
METHODS: The database of our institution was mined for primary mUKA patients implanted with an MB or an AP tibial component (the MB-UKA and AP-UKA groups, respectively) from 2015 to 2018. We compared patient demographics, patient-reported outcome measures (PROMs), and motion analysis data obtained with the Riablo™ system (CoRehab, Trento, Italy). We conducted propensity-score-matching (PSM) analysis (1:1) using multiple variables.
RESULTS: PSM analysis yielded 77 pairs of MB-UKA and AP-UKA patients. At 5 years, the physical component summary (PCS) score was 52.4 ± 8.3 in MB-UKA and 48.2 ± 8.3 in AP-UKA patients (p < 0.001). The Forgotten Joint Score (FJS-12) was 82.9 ± 18.8 in MB-UKAs and 73.4 ± 22.5 in AP-UKAs (p = 0.015). Tibial pain was reported by 7.8% of the MB-UKA and 35.1% of the AP-UKA patients (p < 0.001). Static postural sway was, respectively, 3.9 ± 2.1 cm and 5.4 ± 2.3 (p = 0.0002), and gait symmetry was, respectively, 92.7% ± 3.7 cm and 90.4% ± 5.4 cm (p = 0.006). Patient satisfaction was 9.2 ± 0.8 in the MB-UKA and 8.3 ± 2.0 in the AP-UKA group (p < 0.003).
CONCLUSIONS: MB-UKA patients experienced significantly better 5-year static sway and gait symmetry outcomes than AP-UKA patients. Although the PROMs of the two groups overlapped, MB-UKA patients had a lower incidence of tibial pain, better FJS-12 and PCS scores, and were more satisfied.