“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

Abstract

Introduction: There 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. Objectives: The 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. Methods: Forty-six people with knee OA (68.1 6 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.Results: Approximately 1/3 of participants (n 5 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 1 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 1 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 1 O group and had more dysfunctional pain catastrophizing and pain-related self-efficacy than both other groups. Conclusion: Our 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.

“My Hand Is Different”: Altered Body Perception in Stroke Survivors with Chronic Pain

“…Further, the frequency of altered body perception of the hand, and strength of the association were greater when the region included the hand. This finding of altered body percept in a stroke population with chronic pain is consistent with other chronic pain populations such as knee osteoarthritis (where 30% of people reported perceived swelling of the knee in the absence of any objective swelling [ 46 ]) and complex regional pain syndrome (>50% report disturbances in body perception of the affected region [ 47 , 48 ]). To the authors’ knowledge, this is the first time that the concept of altered body perception in individuals with stroke has been explored in relation to chronic pain.…”

Pain catastrophizing in rheumatic diseases: prevalence, origin, and implications

“…Pain catastrophizing is a dynamic trait that may vary over time in individuals with OA, particularly intensifying during periods of heightened pain [ 113 ]. Information regarding the locations and patterns of pain is also crucial: higher levels of pain catastrophizing were observed in cases of a diffuse type of knee pain [ 114 ] Furthermore, in some individuals with knee OA, there are reports of perceived swelling in the knee without clear evidence, also potentially indicating elevated levels of pain catastrophizing [ 115 ].…”

How do Trained and Prospective Physiotherapists and Radiologic Technologists Face Knee Joint Effusion Profession-Specifically and Interdisciplinary?-A Cross-Sectional Study

“…Additionally, a recent study investigated the association between subjective and objective swelling in patients with knee OA, showing that some people with knee pain experience subjective knee swelling without any ultrasonography detected objective swelling [27].…”