ArticlePain reports
"But it feels swollen!": the frequency and clinical characteristics of people with knee osteoarthritis who report subjective knee swelling in the absence of objective swelling.
Article in Pain reports. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 8 papers, 1 of them a synthesis that pooled it.
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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
8 citing papers in PubMed, 1 synthesis or guideline pooled it, 7 citations in OpenAlex.
- Self-reported questionnaires assessing body perception disturbances in adults with chronic non-cancer pain: a scoping review.Frontiers in pain research (Lausanne, Switzerland) · 2025Pooled it
- Identifying clinically relevant subgroups of patients with knee pain flares for ibuprofen treatment: a secondary analysis.Clinical rheumatology · 2025Trial
- Is There a Difference in Factors Affecting Rest Pain and Pain Intensity during Movement at 1 Year Post-total Knee Arthroplasty?Physical therapy research · 2026Article
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- Pain catastrophizing in rheumatic diseases: prevalence, origin, and implications.Rheumatology international · 2024Review
- "My Hand Is Different": Altered Body Perception in Stroke Survivors with Chronic Pain.Brain sciences · 2022Article
Corrections and comments
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Authors and funding
11 authors at 5 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
introductionThere are complex interactions between pain and perceptions of the painful body part in musculoskeletal disorders, and disruption of various body representations in people with chronic pain.
objectivesThe purpose of this study was to investigate how frequently people with knee osteoarthritis (OA) complain of swelling without objective evidence of swelling, and describe the clinical characteristics of this population.
methodsForty-six people with knee OA (68.1 ± 8.8 years) participated in this cross-sectional study. Subjective and objective swelling was evaluated by knee-specific body perception questionnaire and ultrasonography, respectively. Pain intensity, disability, pain-related beliefs, 2-point discrimination threshold, and quadriceps muscle strength were also evaluated.
resultsApproximately 1/3 of participants (n = 15) had subjective feelings of knee swelling in the absence of objective swelling (S only). Fifteen participants had both subjective and objective knee swelling (S + O group) and 16 had neither subjective nor objective knee swelling (No S/O group). Participants in the S only group had similar pain or disability as those in the S + O group but had more severe pain or disability than those with in the No S/O group. Those in the S only group also had larger 2-point discrimination distance threshold at the medial knee (impaired tactile acuity) than those in the S + O group and had more dysfunctional pain catastrophizing and pain-related self-efficacy than both other groups.
conclusionOur results suggest that about 30% of people with knee OA perceive swelling of the knee in the absence of any objective swelling and that this is accompanied by severe pain and functional disability. Considering altered body image of the knee may reveal relevant treatment-based subgroups in people with knee OA.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.