Gimme a break: Ultrasound for fractures and dislocations

Point-of-care ultrasound can confirm reduction in shoulder dislocation and distal forearm fracture in real time, often shortening emergency department delays. It works best as an adjunct to radiographs, not a replacement, with the strongest evidence in posterior-approach shoulder scans and post-reduction fracture assessment.

Ultrasound for shoulder dislocation

• Posterior shoulder window: The posterior approach is the key scan for both diagnosis and reduction check, with the probe just below the scapular spine to visualize humeral head alignment against the glenoid.
• Glenohumeral separation sign: A normal shoulder shows the humeral head abutting the glenoid, while a negative glenohumeral separation distance supports dislocation and gives immediate bedside feedback after a reduction attempt.
• High diagnostic accuracy: For shoulder dislocation, pooled data show near-perfect sensitivity and specificity, and ultrasound outperforms physical exam alone for both dislocation and associated proximal humeral fracture.
• Faster reduction workflow: Real-time ultrasound can confirm success without waiting on fluoroscopy and appears to shorten reduction time, especially when the clinical clunk is subtle or body habitus obscures the exam. We get into the image-acquisition nuances in the episode.
• Adjunct rather than substitute: Pre- and post-reduction radiographs still matter because fracture identification changes risk, technique, and documentation, even when bedside ultrasound strongly suggests a successful reduction.

Ultrasound for forearm fractures

• Reduction over diagnosis: For distal radius fractures, ultrasound is most useful for guiding and confirming reduction rather than replacing X-rays as the primary diagnostic study.
• Long-axis fracture view: Scanning the distal forearm in the long axis along the dorsal or volar surface lets you watch cortical alignment in real time during manipulation and immediately reassess the endpoint.
• Certainty after manipulation: Ultrasound reduced clinician uncertainty about adequacy of distal radius reduction and prompted repeat manipulation in about 40% of cases when the initial bedside result looked acceptable.
• Comparable alignment assessment: Across adult and pediatric studies, post-reduction ultrasound appears comparable to X-ray or fluoroscopy for judging adequacy, without clear evidence that it improves long-term surgical or remanipulation outcomes.
• Potential throughput benefit: Even without better orthopedic endpoints, ultrasound may decrease emergency department length of stay by replacing delayed imaging checks at the bedside. That practical tradeoff is worth hearing in the chapter.

Limits and practical scope

• Best-supported use cases: The evidence is strongest for shoulder dislocation and distal forearm fracture reduction, where immediate visualization changes bedside decisions in the emergency department.
• Other dislocation caution: For dislocations outside the shoulder, there is little outcome data showing ultrasound improves confirmation, throughput, or success, so it should remain a quick adjunct rather than a definitive test.
• Helpful in equivocal exams: Ultrasound is especially useful when exam findings are uncertain, such as an obese patient, a quiet reduction without a clear clunk, or a forearm fracture with ambiguous post-reduction alignment.
• Resource-limited advantage: When bedside fluoroscopy is unavailable, especially in pediatric forearm reduction, ultrasound offers a practical real-time alternative for checking alignment without leaving the room.

References:

1. Gottlieb M, et al. Ultrasound for the diagnosis of shoulder dislocation and reduction: A systematic review and meta-analysis. Acad Emerg Med. 2022 Aug;29(8):999-1007. Epub 2022 Feb 27. PMID: 35094451
2. Akyol C, et al. Point-of-care ultrasonography for the management of shoulder dislocation in ED. Am J Emerg Med. 2016 May;34(5):866-70. Epub 2016 Feb 16. PMID: 26935225.
3. Attard Biancardi MA, et al. Diagnostic accuracy of point-of-care ultrasound (PoCUS) for shoulder dislocations and reductions in the emergency department: a diagnostic randomised control trial (RCT). Emerg Med J. 2022 Sep;39(9):655-661. PMID: 34544780.
4. Nema SK, et al. Ultrasound-Guided Manipulation does not Prevent Malalignment Over Landmark-Based Fracture Reduction in Distal Radius Fracture (Colles). J Emerg Trauma Shock. 2023 Apr-Jun;16(2):35-42. Epub 2023 May 25. PMID: 37583377.
5. Smiles JP, et al. Bedside ultrasound in the emergency department for reduction and radial manipulation of distal radial fractures. Emerg Med Australas. 2020 Dec;32(6):1015-1020. Epub 2020 Jun 25. PMID: 32583959.
6. Socransky S, et al. Ultrasound-Assisted Distal Radius Fracture Reduction. Cureus. 2016;8(7):e674. Published 2016 Jul 7. PMID: 27551652
7. Auten JD, et al. Comparison of pediatric post-reduction fluoroscopic- and ultrasound forearm fracture images. Am J Emerg Med. 2019;37(5):832-838. PMID: 30093180
8. Gillon JT, et al. Comparison of ultrasound-guided versus fluoroscopy-guided reduction of forearm fractures in children. Emerg Radiol. 2021;28(2):303-307. PMID: 33030662