index.qmd

# Report {.unnumbered}

## Prepared for {.unnumbered}

This report was made to help doctors, physical therapists, or any clinician who works with ACLR patients during recovery. Our focus was to offer insight into how flexion and extension strength progress over time after surgery.

## Problem Statement

The knee has two primary functions: flexion and extension. Both these strengths can be measured isokinetically or isometrically, and at varying degrees. Isokinetic strength is a measurement of how strong the movement of the patient’s limb is, while isometric strength is a measure of how strong the patient’s limb is without movement. The variables we used utilize the average limb symmetry index (LSI) by dividing the strength of the uninvolved limb by the strength of the involved limb. This accounts for external factors contributing to the strength differences between patients. After injury, and even after surgery, both these strengths have decreased in the affected limb. Rehabilitation aims to get a patient’s knee strength back to where they were before surgery. To explore the successes and failures of rehab, we asked the following questions:
Do flexion strength and extension strength progress differently during recovery?
How might strength tests relate to more holistic measures of recovery, such as ACL-RSI?

## Analysis

Based on our visuals, we can see some clear trends in flexion and extension strength over recovery time. Our first graph shows the relationship between isokinetic flexion and extension strength, five to seven months post-operation, over a range of ages. From the graph, we concluded that regardless of the patient’s age, their flexion strength at this stage in recovery is better than their extension strength. We can even see that flexion strength is generally around a value of 100, which means that the involved limb is operating at the same strength as the uninvolved limb. 

![Strength vs Age](strengthreg.jpg)

In our second graph, we looked at the trends in isokinetic and isometric LSI flexion and extension strengths during early and late recovery. A gap between flexion and extension strength LSI exists in early recovery, and still exists 13 to 24 months after surgery. This trend exists for both isokinetic and isometric data. Even though both kinds of knee strength improve, doctors ought to try and close the gap between them.

![Spaghetti Plot](spaghetti.jpg)

In our third graph, we looked at a couple of patients’ journeys through recovery by plotting their strength against psychological readiness. We concluded that recovery is not linear and requires a balance between physical readiness and mental confidence. When comparing the two graphs, we noticed that flexion strength seems to be more consistent with an upward trend in relation to the RSI score across patients, suggesting a more consistent relationship between flexion strength and confidence, indicating a gap between flexion and extension strength rehab programs. 

![Connected Scatter](connected.jpg)

## Conclusion

Physical therapists should pay special attention to extension strength during rehab, as patients tend to have weaker extension than flexion. In addition to strength, nonlinear patterns between strength and psychological improvement underline the need for a holistic recovery approach.