The anatomic total shoulder arthroplasty (TSA) is indicated when both sides of the scapulo-humeral joint are worn out, and when the rotator cuff remains intact and with no sign of motricity defficiency. The TSA requires a good glenoid bone stock, and will be contra-indicated whenever there pre-exist a permanent instability in the joint. The UNIC anatomic system is characterized by: Compatible with all and any humeral base: primary, fracture or revision, cemented or cementless Oval humeral heads available in 5 combinations of diameter/thickness Efficient multi-position Head offset management based on twin crossed ratchets and twin taper modulus Optionnal 6° angled modulus to fine tune for increased varus/valgus or ante/retroversion Identical mismatch through the range unabling match of all heads with all sizes of glenoid Low 2mm mismatch reduces sheer stresses on the glenoid component