Assessment of 99mTc-NTP 15-5 Uptake on Cartilage, a New Proteoglycan Tracer

Inclusion Criteria:

Inclusion criteria specific to group 1:

\- Patient with painful unilateral osteoarthritis of the knee as femorotibial pattern defined by a radiographic score of 0/1 from Kellgren / Lawrence and an average WOMAC score\> or equal to 4 and by minor disorders at MRI (MOCART 2.0 score\> 70).

Inclusion criteria specific to group 2:

* Patient with non-metastatic breast cancer, hormone receptor positive, HER2 negative, with indication for adjuvant therapy with aromatase inhibitor; treatment not yet started.
* Age \<60 years

Common inclusion criteria:

* Patient with at least 31 healthy joints (based on clinical assessment)
* signed written informed consent.
* Affiliation to a health insurance scheme.
* For women of childbearing age : negative serum pregnancy test at inclusion (less than 7 days prior injection of 99mTc-NTP 15-5).
* Willing and able to comply with study visits, treatment, exams and the protocol.

Exclusion Criteria:

* Patients \<18 years of age.
* Pregnant or lactating patient.
* BMI\> 30
* History of known allergy to excipients contained in the solution of 99mTc-NTP 15-5
* Chronic inflammatory rheumatism (rheumatoid arthritis, spondyloarthropathy, psoriatic arthritis, etc.) diffuse arthritis (at least 3 joints affected), autoimmune connectivitis, fibromyalgia.
* Known chronic joint pathology: osteoarthritis affecting at least 3 joints, autoimmune disease, inflammatory rheumatism (except unilateral knee arthritis).
* Persons deprived of their liberty, under guardianship / curatorship, or safeguard of justice.
* Treatment with NSAIDs or cessation of less than 48 h.
* Inability to comply with medical requirement / follow-up of the trial for geographic, family, social or psychological reasons. These conditions should be discussed with the patient before registration in the study.