Functional and biomechanical outcomes after using biofeedback for retraining symmetrical movement patterns after total knee arthroplasty: a case report

Abstract

Study design: Case report.

Background: Rehabilitation that includes progressive quadriceps strengthening after total knee arthroplasty (TKA) leads to superior outcomes. Though patients with TKA show marked functional improvement after outpatient physical therapy, they continue to adopt movement asymmetries characterized by reduced knee excursion on the operated limb and excessive loading on the contralateral limb. The purpose of this case report was to describe the functional and biomechanical improvements in a patient who, after TKA, participated in a novel physical therapy protocol that included retraining of symmetrical movement patterns.

Case description: A 57-year-old female with unilateral knee osteoarthritis was evaluated prior to TKA and at 3 and 10 weeks after surgery. Postoperative rehabilitation included progressive quadriceps strengthening and movement retraining that consisted of visual, verbal, and tactile feedback to promote symmetrical weight bearing during strengthening exercises and functional activities. Outcomes were compared to a historical cohort of patients with TKA.

Outcomes: Prior to TKA, the patient scored below average on all functional measures and walked with knee biomechanics that were abnormal and asymmetrical. After symmetry retraining, her knee motion and moments were restored to normal levels. The patient also walked with greater magnitude and more symmetrical knee excursion compared to a cohort of similar patients.

Discussion: This case report describes the use of a novel rehabilitation protocol intended to improve walking biomechanics and functional outcomes after TKA. Restoration of symmetrical movement patterns could improve long-term outcomes of TKA. Further research is needed to evaluate the effectiveness and implementation of similar rehabilitation strategies in a wide range of patients after TKA.

Level of evidence: Therapy, level 4.

FIGURE 1

The SymSlide provides visual feedback on weight distribution during closed-chain knee exercises (A). To increase resistance on the SymSlide, the angle of inclination of the sled portion can be increased. In this case, the patient is putting more force through the right foot, as demonstrated by the ball drifting toward the right side of the target area (B).

FIGURE 2

The patient is provided with visual feedback on weight distribution between limbs during sit-to-stand functional retraining exercises (A). In this case, the patient’s weight is shifted over her right limb during the movement (B).

FIGURE 3

The patient who participated in biofeedback retraining (case) showed improvement in knee kinetics during stance (top) and knee flexion excursion during loading response (bottom). Her values after biofeedback retraining were greater than the comparative group of 4 individuals with total knee arthroplasty who were treated with a progressive strengthening program (historical cohort). Abbreviations: IC, initial contact; TO, toe-off.