Background and purpose - Essential for safe and timely hospital discharge, inpatient functional recovery following lower limb arthroplasty is also variable. A previous systematic review reported moderate and conflicting levels of evidence regarding patient-related predictors of inpatient recovery for primary total hip arthroplasty (THA). A systematic review of surgical prognostic factors for inpatient recovery following THA or total knee arthroplasty (TKA) is yet to be undertaken. We identified patient and surgical prognostic factors for inpatient functional recovery following THA and TKA; determined whether inpatient functional recovery varies between these procedures; and established whether validated outcome measures relevant to the patient's functional requirements for hospital discharge are routinely assessed.Patients and methods - Critical Appraisal Skills Programme checklists assessed methodological quality, and a best-evidence synthesis approach determined the levels of evidence supporting individual prognostic factors. PubMed, CINAHL, Embase, Scopus, and PEDro databases were searched from inception to May 2019. Included studies examined patient or surgical prognostic factors and a validated measure of post-operative function within 2 weeks of primary, unilateral THA or TKA.Results - Comorbidity status and preoperative function are supported by a strong level of evidence for TKA. For THA, no strong level of evidence was found for patient-related prognostic factors, and no surgical factors were independently prognostic for either arthroplasty site. Limited evidence supports fast-track protocols in the TKA population.Interpretation - Preoperative screening and optimization is recommended. Assessment of Enhanced Recovery Pathways using validated outcome measures appropriate for the early postoperative period is warranted.