A Clinical Trial of a Theory of Planned Behavior–Guided Staged Rehabilitation Nursing Program After ACL Reconstruction: Effects on Knee Function and Pain

Objective To evaluate the effects of a theory of planned behavior (TPB)-guided staged rehabilitation nursing program on functional recovery, pain, psychological constructs, adherence, health-related quality of life, and postoperative complications after primary anterior cruciate ligament (ACL) reconstruction. Methods In this single-center randomized controlled trial, 124 patients undergoing primary ACL reconstruction were allocated to a TPB-guided staged rehabilitation nursing group ( n = 62) or a conventional rehabilitation nursing group ( n = 62). All patients received a standard phase-based rehabilitation protocol; only the nursing/behavioral support differed. Primary outcomes were Lysholm and International Knee Documentation Committee (IKDC) subjective scores at 3 and 6 months. Secondary outcomes included pain (visual analogue scale [VAS]), knee range of motion (ROM), TPB-related psychological constructs (attitude, subjective norm, perceived behavioral control, behavioral intention), adherence (≥80% of prescribed exercises), health-related quality of life (36-item short-form health survey [SF-36] physical component summary [PCS]/mental component summary [MCS], EuroQol-5 dimension [EQ-5D]), and postoperative complications. Results Baseline characteristics were comparable. At 6 months, the intervention group showed higher Lysholm (91.2 vs. 83.5) and IKDC (86.7 vs. 79.4) scores (both P < 0.001), lower VAS pain, and greater knee flexion. TPB constructs were significantly higher from 6 weeks onward (all P < 0.001), paralleled by higher adherence at 3 and 6 months (78.6% vs. 55.6%; 71.4% vs. 48.1%). SF-36 PCS/MCS and EQ-5D scores were superior in the intervention group. Complication rates were low and similar between groups. Conclusions TPB-guided staged rehabilitation nursing safely improves psychological determinants, adherence, functional outcomes, pain, ROM, and health-related quality of life after ACL reconstruction.