Bade M, et al. - The purpose of this study was to analyze the association between performance on a clinical quadriceps activation battery (QAB) with activation measured by doublet interpolation and recovery of quadriceps strength and functional performance following total knee arthroplasty (TKA). The results suggested that poor performance on the QAB early after total knee arthroplasty is related to poor quadriceps activation and poor recovery in the early postoperative period. Patients in the LOW quadriceps activation battery (QAB) group took 3 months to recover to the same level as the HIGH QAB group. Moreover, the quadriceps activation battery may be useful in distinguishing individuals who need specific interventions to target activation deficits or different care pathways in the early postoperative period to speed recovery after TKA.