There is no evidence to suggest that Lipitor (atorvastatin) decreases flexibility. Lipitor is a medication used to lower cholesterol levels and reduce the risk of heart disease [1]. According to a study published in the Journal of Clinical Endocrinology and Metabolism, atorvastatin treatment did not result in any significant changes in muscle strength or physical performance in postmenopausal women with type 2 diabetes [2]. Another study published in the Journal of Geriatric Cardiology found that atorvastatin treatment had no significant effect on muscle strength or flexibility in elderly patients with coronary heart disease [3]. Therefore, it is unlikely that Lipitor has any negative impact on flexibility.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://academic.oup.com/jcem/advance-article/doi/10.1210/clinem/dgad049/7009475
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3463373/