I have studied your case with diligence.
As per your history there is possibility of mono articular arthritis.
mono articular Rheumatoid arthritis
may involve large joints and early morning stiffness
in joints, does she have such complain?Ankylosing spondylitis
typically involve spine and hips with other large joint also. There is reduced chest function in this disease.
Harmone imbalance like hypothyroidism
also leads to similar complain.so check your thyroid profile.
Hope this answers your query. If you have additional questions or follow up queries then please do not hesitate in writing to us. I will be happy to answer your queries.
Wishing you good health.