 At visit 1, after informed consent and screening for inclusionexclusion criteria, patients will undergo: index joint X-ray, laboratory tests; history, physical examination, index joint pain history, comorbidity and medication history; patient pain assessments, WOMAC and SF-36; and blinded index joint, neurological examination, TST and TUG tests. 50 patients will be randomized to receive either IA BoNTA 100 units or sterile saline in the index joint. FU phone interviews at 2 and 4-weeks will include pain assessments, WOMAC, patients global assessment and adverse effects. Interim visits at 2, 3 and 4-months will be identical to visit 1, but will also include patients and physicians global assessment and there will be no joint injection. End of study visit at 6 months will be identical to interim visits with the addition of index joint X-ray and laboratory tests. 