Basic Setup: The experiment involves 100 hind legs from 50 rats. This means each rat's pair of hind legs is considered in the study. Injections are given in the left knee, while the right knee is used as a control for comparison. This control method assumes the right knee remains untreated and can thus serve as a baseline or standard for comparing the effects of treatments administered to the left knee. Phosphotungstic acid (PTA) staining is employed to enhance tissue contrast in the imaging. This involves using a 1% PTA solution in 70% ethanol, with the samples being stained for 22 hours prior to scanning. Experimental Groups and Timeline: Collagenase Injection Group: Rats in this group received an injection of collagenase (an enzyme that breaks down collagen) into their left knee. This group is further divided based on when the rats were euthanized (sacrificed) for analysis: -10 days post-injection (N=10) -60 days post-injection (N=10) Sham Injection Group: Rats in this group received a sham injection (saline) into their left knee. This group is also divided based on the euthanasia timeline: -10 days post-injection (N=10) -60 days post-injection (N=10) Naive Group: This group did not receive any injection but was included for comparison. They were also divided based on when they were euthanized: -10 days (N=5) -60 days (N=5) Imaging and Documentation: The knees of the rats were imaged using a Bruker 1272 µCT scanner, which is a type of micro-computed tomography used for detailed imaging. More detailed information about the dataset is provided in a readme file associated with the data.

2024