The purpose of this study was twofold: (i) to test whether the level of quadriceps femoris strength asymmetry, lower limb extensor power asymmetry, residual knee pain, and/or balance confidence explain the level of inter‐limb joint mechanical asymmetry during a high‐demand, decline walking, task at both 3 and 6 months following TKA and (ii) to compare the postoperative recovery on inter‐limb joint mechanical and clinical outcomes over time. Level of evidence: Although quadriceps femoris strength asymmetry does improve after surgery from preoperatively levels, deficits continue to be observed years following surgery.3 It is uncertain if restoration of the surgical limb strength ever reaches that of the contralateral limb or the strength of healthy‐matched peers.52 Our findings showed significant quadriceps femoris strength improvement in both the surgical and non‐surgical limbs over time, however, the residual inter‐limb asymmetry remained. The three maximal trials were averaged for a single composite score of maximal torque output (Nm) for each limb. Trajectory data were recorded using a 10‐camera motion analysis system (Vicon, Oxford Metrics Ltd., London, UK) at a sampling rate of 200 Hz and analog data were collected on a dual‐belt treadmill instrumented with two force platforms (Bertec Corp; Columbus, OH) at a sampling rate of 1,000 Hz. Motion analysis and clinical measures were collected at both 3 (mean, 3.3 ± 0.2) and 6 (mean, 6.2 ± 0.3) months following surgery. No other variable showed significant change between 3 and 6 months. Quadriceps/hamstrings co-activation increases early after total knee arthroplasty. eCollection 2018.
Total knee arthroplasty: muscle impairments, functional limitations, and recommended rehabilitation approaches. We chose valid and reliable metrics for pain and balance confidence that did not reveal substantive residual deficits during testing. Preoperative quadriceps weakness preferentially predicts postoperative aberrant movement patterns during high-demand mobility following total knee arthroplasty. You have to lock your knee during walking and rely on your other leg to get in and out of a car. Get the latest research from NIH: https://www.nih.gov/coronavirus.
Quadriceps femoris strength index as an individual predictor had a medium to large effect of explaining inter‐limb MT (Cohen's f2 = 0.16) and MK (Cohen's f2 = 0.27) asymmetry above and beyond what the other predictors explained in the model. Journal of athletic training. Christensen JC, Mizner RL, Foreman KB, Marcus RL, Pelt CE, LaStayo PC. A warm‐up session of two submaximal (50% and 75%) and one maximal (100%) contractions were performed, prior to collecting three maximal isometric contractions. ( Log Out / Imagine being not only weak but unable to even contract the muscle. These data speak to the need for further research to help optimize postoperative mobility recovery and setting appropriate expectations preoperatively. For example, inadequate motor retraining during the recovery period could be an important rehabilitative component currently underutilized in this patient population. How common targets of postoperative care, such as muscle weakness, lower limb extension power, residual knee pain, and poor balance confidence can influence asymmetrical limb loading remains unclear. One identified risk factor for ACL tear is weak hamstrings relative to the quadriceps2, while quadriceps weakness is a risk factor for anterior knee pain3. Compensatory strategies observed prior to surgery have been shown to be retained up to 18 months following surgery.53 Quadriceps femoris deficits are apparent at 4–6 months and persist 1–3 years following surgery, suggesting rehabilitation strategies in this area need to be amplified.3 Underutilization of the surgical limb with daily and recreational activities could be preventing adequate stimuli needed to maximize muscle tissue for optimal strength recovery.