Self‐Reported Knee Instability Before and After Total Knee Replacement Surgery

Abstract

Objective. To determine the prevalence and burden of pain and activity limitations associated with retaining presurgery self-reported knee instability 6 months after total knee replacement (TKR) surgery and to identify early potentially modifiable risk factors for retaining knee instability in the operated knee after TKR surgery. Methods. A secondary analysis was performed using measures obtained from 390 participants undergoing primary unilateral TKR and participating in a randomized clinical trial. Self-reported knee instability was measured using 2 items from the Activities of Daily Living Scale of the Knee Outcome Survey. Outcome measures were knee pain (range 0-20) and physical function (range 0-68) on the Western Ontario and McMaster Universities Arthritis Index (WOMAC), stairclimb power, 50-foot walk time, knee range of motion, and isometric knee flexion and extension strength. Results. In this study, 72% of participants reported knee instability just prior to surgery, with 32% retaining instability in the operated knee 6 months after surgery. Participants retaining operated knee instability had significantly more knee pain and activity limitations 6 months after surgery, with mean 6 SD WOMAC scores of 4.8 6 3.7 and 17.5 6 11.1, respectively, compared to participants without knee instability, with 2.9 6 3.1 and 9.8 6 9.2. The multivariable predictor model for retained knee instability included a high comorbidity score (>6), low stair-climb power (<150 watts), more pain in the operated knee (>7 of 20), and younger age (<60 years). Conclusion. Self-reported knee instability is highly prevalent before and after TKR surgery and is associated with a considerable burden of pain and activity limitation in the operated knee. Increasing lower extremity muscle power may reduce the risk of retaining knee instability after TKR surgery.

Self‐reported knee instability associated with pain, activity limitations, and poorer quality of life before and 1 year after total knee arthroplasty in patients with knee osteoarthritis

“…The percentages of patients reporting knee joint instability pre‐ and postoperatively, as well as the percentage of patients with retained knee instability were in accordance with previous studies . Preoperatively, patients with knee instability had more pain and more activity limitations as compared with those with no instability, which corresponds to previous studies . Our study found similar results for patients reporting knee instability 1 year postoperatively.…”

“…These results are in line with the study of Fleeton et al, a randomized controlled trial where a selected patient population was used that excluded the worst patients (e.g., patients aged 75 and over, those who had previously undergone lower limb surgery, or those with severe comorbidities) . In addition, one group of patients received an intensive postoperative exercise programme that potentially influenced the perception of knee joint instability . This is different from our study, in which both young and old patients could have undergone uncontrolled interventions: A situation typical of clinical care.…”

“…The differences in postoperative pain and activity limitations between those with and without knee joint instability exceeded the minimal clinically important difference (range between 8 and 10 for both subscales) and are therefore clinically significant . These results are in line with the study of Fleeton et al, a randomized controlled trial where a selected patient population was used that excluded the worst patients (e.g., patients aged 75 and over, those who had previously undergone lower limb surgery, or those with severe comorbidities) . In addition, one group of patients received an intensive postoperative exercise programme that potentially influenced the perception of knee joint instability .…”

A machine learning approach using gait parameters to cluster TKA subjects into stable and unstable joints for discovery analysis

“…Across all individuals who have undergone TKA, quadriceps and hamstring weaknesses often prevail after surgery [ 29 - 32 ] and patients have a 30 to close to 50% deficit compared with age-matched healthy controls [ 29 ]. Only a single study provides insight on the neuromuscular function specific to individuals with unstable knees following TKA, suggesting that they have significantly less extensor strength than stable subjects six-weeks post-surgery [ 1 ]. While the methodologies of our own study do not include information specifically on muscle strength, individuals with unstable knees following TKA exhibited a significantly lower rectus-femoris-to-biceps-femoris coactivity ratio during late stance and swing possible hinting to lower extensor strength, highly suggestive of a neuromuscular adaptation.…”

Construction and validation of chronic pain prediction model after total knee arthroplasty

“…Some studies have also shown that instability of the knee joint after TKA surgery can increase knee pain and movement limitations for six months after the surgery. 27 This may be due to poor rehabilitation that may lead to muscle strength decline and joint stiffness that affect patient’s quality life, and increase pain perception. 28 Additionally, postoperative complications may also lead to low HSS scores.…”