Difficulties in recruiting and implementing the study design due to missing ressources.

The goal of this clinical trial is to prospectively evaluate the potential benefits of injections with Augmented Reality enhanced Ulrasound versus standard Ultrasound or fluoroscopy participants where assigend for fluoroscopic joint injections oder for Ultrasound guided injection.

The main question[s] it aims to answer are:

• The primary objective is to evaluate the duration of the different interventions
• the count of needle passes
• assess the reduction of radiation exposure using AR US rather than fluoroscopic guidance for joint injections

Patients assigned for standard Ultrasound or fluoroscopic joint injection are informed about the trial. Participants are randomly assigned to the study or control intervention. 1:1 randomization is used.

In both groups, data on duration of the intervention, count of needle passes, correctness of injection location and radiation exposure will be collected. The outcome measures will be compared between the groups.

Inclusion Criteria:

• - Patients 18 to 99 years of age
• Patients assigned for fluoroscopic guided injections (including MR arthrographies)
• Patients assigned for US guided injections (including MR arthrographies)

Exclusion Criteria:

• - Patients who are not willing to be part of the study
• Contraindication against fluoroscopic guided injection
• Women who are pregnant or breast feeding (Pregnancy assessment is part of the routine prior to fluoroscopic joint injections. No pregnancy test will be done for this study.)

The assignment into the study groups is going to be performed by 1:1 randomization using randomisation cards which are drawn by author-ised study staff.