A positive 3-phase bone scan can be seen in the early postoperative state, periprosthetic fracture, aseptic prosthetic loosening, and periprosthetic infection. Postoperative change and fracture healing tend to decrease over time. Fracture confirmation can also be identified with anatomic imaging (eg, radiographs, CT with metal artifact reduction techniques). SPECT/CT also has the potential to differentiate symptomatic from asymptomatic scapular notching associated with reverse shoulder prostheses [30]. Normal uncomplicated postoperative change tends to decrease over time and up to 2 years or longer after surgery [21,22], whereas aseptic loosening generally tends to progress. The specificity of bone scans for periprosthetic complications increases in older prostheses once the postoperative remodeling has stabilized. Bone Scan Shoulder Tc-99m single-phase bone scan imaging is a sensitive modality for the diagnosis of loosening in the setting of normal radiographs but remains low in specificity because the imaging findings can overlap with other abnormalities such as postoperative bone remodeling, periprosthetic fracture, and infection [30]. Normal uncomplicated increased periprosthetic uptake related to postoperative bone remodeling tends to decrease over time and up 2 years or longer after surgery [21,30], whereas aseptic loosening generally tends to progress. The specificity of bone scans for periprosthetic fracture, loosening, or infection increases in older prostheses once the postoperative remodeling has stabilized. CT Shoulder CT plays an important role in the imaging evaluation of a patient with potential loosening that may be missed or incompletely evaluated with radiographs [10,47]. CT provides a better means of evaluating the hardware components and surrounding bone stock [48]. CT can also assess changes in component alignment over time [49].
Imaging After Shoulder Arthroplasty PCAs. A positive 3-phase bone scan can be seen in the early postoperative state, periprosthetic fracture, aseptic prosthetic loosening, and periprosthetic infection. Postoperative change and fracture healing tend to decrease over time. Fracture confirmation can also be identified with anatomic imaging (eg, radiographs, CT with metal artifact reduction techniques). SPECT/CT also has the potential to differentiate symptomatic from asymptomatic scapular notching associated with reverse shoulder prostheses [30]. Normal uncomplicated postoperative change tends to decrease over time and up to 2 years or longer after surgery [21,22], whereas aseptic loosening generally tends to progress. The specificity of bone scans for periprosthetic complications increases in older prostheses once the postoperative remodeling has stabilized. Bone Scan Shoulder Tc-99m single-phase bone scan imaging is a sensitive modality for the diagnosis of loosening in the setting of normal radiographs but remains low in specificity because the imaging findings can overlap with other abnormalities such as postoperative bone remodeling, periprosthetic fracture, and infection [30]. Normal uncomplicated increased periprosthetic uptake related to postoperative bone remodeling tends to decrease over time and up 2 years or longer after surgery [21,30], whereas aseptic loosening generally tends to progress. The specificity of bone scans for periprosthetic fracture, loosening, or infection increases in older prostheses once the postoperative remodeling has stabilized. CT Shoulder CT plays an important role in the imaging evaluation of a patient with potential loosening that may be missed or incompletely evaluated with radiographs [10,47]. CT provides a better means of evaluating the hardware components and surrounding bone stock [48]. CT can also assess changes in component alignment over time [49].