## 4 Discussion
### Associations with AKPS  
The AKPS is a qualitative tool used to capture the perception of pain in those with PFP [49]. Intriguingly, within the PFP group, the AKPS score demonstrated a moderate positive correlation with the impulse (r = 0.58) and RSI (r = 0.50) values associated with the uninjured limbs, whereby approximately 25-34% of the variability in performance could be explained by the AKPS scores alone. More importantly, this indicates that key jumping-based metrics could be well suited to identify dynamic deficits in people with PFP as it may capture the motor control hesitancy of this group during dynamic jumping tasks. A recent systematic review found that RSI relates to improved performance in physical capacities and sport performance tasks, yet its utility across different injuries is under-researched [50]. Isometric strength in the injured limb was also moderately correlated with the AKPS (r = 0.46), implying that 21% of the variability in strength can be explained by the qualitative perceptions of pain captured by the AKPS score. Other studies on different performance variables such as sit to stand, trunk side flexion, and hip mobility also found similar correlations with the AKPS [51]. Therefore, the AKPS can account for a meaningful portion of the performance in objective performance measures and can be used to help with tracking progress in the rehabilitation of PFP. Stated differently, a psychological measure of pain, such as the AKPS score, appears to capture dynamic task variability where pain apprehension may be a limiting factor in task performance. Importantly, the simplicity of both the experimental setup and completion of the AKPS would allow for the more frequent monitoring of the rehabilitation process, which in turn would facilitate more appropriate decision-making processes. Some research has shown that exercise selection for the treatment of PFP is often too simplistic or lacks the appropriate progression for exercise-based therapy to be effective [52]. As such, more regular monitoring could guide practitioners to more valuable and/or appropriate exercise selection based on the performance outcomes.  
Although there were several benefits connected with this study, there were also a few limitations. Participants did not follow a standardised rehabilitation program as they came from different clinical practices and were therefore subject to the guidelines implemented by their resident practitioner. Future studies may control the specific intervention program to determine their effect on the measured parameters. However, by demonstrating the utility of force plates (and the metrics derived from them) across various individualized programs, the present study provides broad applicability and supports the tools' relevance in different clinical contexts. Further, the ratio of males versus females differed between the control and PFP groups, although no other anthropometric differences were apparent. We used force plates to evaluate kinetic and kinematic parameters, which may not necessarily be accessible to practitioners. Therefore, although alternative lower-cost technologies (e.g., Mydump2) can provide similar metrics, it is unclear whether these tools can exhibit similar diagnostic insights, therefore providing an avenue for future research.