It depends almost entirely on grade and symptoms. Grade 1 with no symptoms: no. Grade 4: yes. Grade 2 and 3 are decided by how often the dog is lame, whether it is progressing, and the dog's age, with surgery favoured in young dogs with frequent symptoms and monitoring favoured in older dogs with occasional skips.
Ask how often the kneecap is actually out, and what it is costing the dog. A dog that skips twice a week and is otherwise flying is a different proposition from a dog that will not jump on the couch anymore. Owners are the only witnesses to this, which means your observations, ideally a week of notes or some video, are real diagnostic data. Bring them to any opinion, including ours.
One more honest note: an unstable kneecap changes the mechanics of the whole knee, and a proportion of higher grade patella dogs go on to rupture their cruciate ligament. That link is part of the case for fixing significant luxations in young dogs, and part of why "wait and see" should be an active plan with reviews, not a shrug.
The grade, the imaging and the quote reviewed independently. From $250.
Muscle strength helps symptoms, and physiotherapy is a genuinely useful part of managing low grades. But no exercise or brace changes the bone anatomy that lets the kneecap slip. For structural problems, the structural fix is surgery; everything else is management.
Monitor deliberately: weight in the healthy range, note any skipping, review at each vet visit. Doing nothing on purpose with reviews is fine. Discovering at age eight that the knee quietly became grade 3 is what we are trying to avoid.
An independent written opinion on the diagnosis, the technique and the quote. From $250.