A patellar cutting guide is particularly useful in a method of minimally invasive knee arthroplasty in which an incision is made along the medial or lateral aspect of a patient's knee, exposing the knee joint. The patellar cutting guide includes a clamp configured to be located exterior to the knee over the anterior portion of the patella, a stop having at least one portion configured to extend through an incision to a location posterior to the patella, and a cutting guide defining a cutting slot. The clamp may have outwardly extending spikes for passage through the tissue overlying the patella and into engagement with the patella. The stop is movable relative to the clamp and/or cutting guide. In one embodiment, the cutting guide is offset laterally and posteriorly relative to the clamp so that the slot is aligned with a medially or laterally-formed incision in the knee.