Platelet-rich plasma is widely used for symptomatic knee osteoarthritis, yet the ideal formulation remains debated. This double-blind randomized trial compared leukocyte-rich PRP with leukocyte-poor PRP in patients with mild-to-moderate knee osteoarthritis who received three weekly injections. Both groups improved over follow-up, but the study did not find a meaningful difference between the two preparations in patient-reported outcomes. This is clinically useful because it suggests that the presence or removal of leukocytes alone may not determine whether PRP improves symptoms. The trial also illustrates why the PRP literature can be difficult to interpret: treatment protocols differ in platelet concentration, leukocyte content, injection number and patient selection, making direct comparisons across studies challenging. For clinicians, the practical lesson is to avoid assuming that one commercially marketed PRP formulation is automatically superior. Patients considering PRP should be counselled that symptom improvement is possible, but the evidence does not establish a single optimal preparation or prove consistent structural disease modification. PRP should therefore be integrated into an overall osteoarthritis treatment plan, with attention to diagnosis, severity, functional goals and the evidence supporting other nonoperative options.