Paget's disease (PD) is the second most common bone disorder after osteoporosis. It is a benign bone dystrophy characterized by a focal increase in bone remodeling associated with morphological and functional abnormalities of osteoclasts. We conducted a retrospective study of 40 cases of MP in the internal medicine department of CHU Hédi Chaker, Sfax, over a 16-year period. Our series included 22 women (55%) and 18 men (45%) with an average age of 69.7 + 9.7 years (52 and 86 years). Pain was present in 33 patients (82.5%). It was mechanical (24 cases), inflammatory (4 cases) and permanent (5 cases). It affected the lumbar spine in 18 cases (45%), the dorsal spine in 4 cases (10%), the cervical spine in 10 cases (25%), the hip in 19 cases (45%), the shoulder in 15 cases (38%) and the knee in 10 cases (25%). Deformities were noted in 5 cases (12.5%): characteristic curvature of the left leg in 1 case, of the right leg in 2 cases and of the right arm in 2 cases. An increase in skull volume was noted in one patient.