Patient-specific psychological characteristics and personality structure affect post-operative outcomes and readiness to return to sport following medial patellofemoral ligament reconstruction.

Purpose: The purpose of this study was to evaluate the influence of patient-specific psychological characteristics and personality structure on the functional outcomes and return to sports (RTS) after isolated medial patellofemoral ligament (MPFL) reconstruction for patellofemoral instability (PFI). Methods: Patients who underwent isolated MPFL reconstruction for PFI between 2017 and 2020 were retrospectively included. Minimum 18 months post-operatively, patient-reported outcome measures, including the Banff Patellofemoral Instability Instrument 2.0 (BPII 2.0), visual analogue scale (VAS) for pain and function, Tegner activity scale (TAS) and Marx activity rating scale (MARS) were evaluated. The MPFL-Return to Sport after Injury (MPFL-RSI) scale was used to determine psychological readiness to RTS. Kinesiophobia was measured using the Tampa Scale of Kinesiophobia (TSK), and the tendency to catastrophize pain was measured using the pain catastrophizing scale (PCS). Self-efficacy was assessed using the General Self-Efficacy Short Scale-3 (GSE-3 scale). Personality structure was classified using a variant of the Big Five Inventory (BFI-10). The Live Orientation Test (LOT-R) was used to measure generalized optimism/pessimism. The primary outcome was the correlation between MPFL-RSI score and BPII 2.0. The data were statistically analyzed using Pearson or Spearman correlation analysis as appropriate. Results: In total, 54 patients (24 ± 8 years, follow-up: 35.8 ± 12.8 months) were included. MPFL-RSI and BPII 2.0 correlated inversely with VAS for pain and function, fear of movement (TSK) and pain catastrophizing (PCS). Both the MPFL-RSI and BPII 2.0 correlated significantly with self-efficacy as well as with each other. The MPFL-RSI correlated inversely with the personality characteristic 'neuroticism' (BFI-10) and positively with sporting activity (MARS). Conclusion: Individual psychological characteristics and personality structure significantly correlate with the functional outcome and psychological readiness to RTS after MPFL reconstruction. Increased self-efficacy, reduced pain catastrophizing and exercise phobia are associated with better post-operative knee function. Preoperative assessment and consideration of these factors may inform tailored prehabilitation. Level of Evidence: Level IV.