# Ultrasound-Guided Procedures in Common Tendinopathies at the Elbow: From Image to Needle
## 3 Common Elbow Pathologies
### Distal Biceps Tendingupathy
#### 3.3.2 US Scanning and Guided Injection  
The assessment of the DBT using US imaging can be technically challenging given its oblique course. There are different ultrasound approaches to assess the DBT. It is beneficial to examine the patient lying supine with his or her upper limb extended along the trunk. The patient is asked to actively supine the forearm while the examination bed provides a suitable resistance. The transducer is first placed in the transverse plane. When the DBT is identified lateral to the brachial artery, the probe is turned 90\({}^{\circ}\) to visualize the tendon in its long axis (Figures 9a,b and 10a). To reduce the unsolicited anisotropic artifact given by the tendon's oblique course, the examiner should perform a \"heel-toe\" maneuver with the probe to obtain the optimal image to assess the DBT. Rotating the transducer towards the pronator teres muscle, the lacertus fibrosus insertion will appear, attaching to the superficial fascia of the muscle mentioned before. To visualize the insertion of the DBT on the radial tuberosity, the elbow is flexed, the forearm is fully pronated, and the wrist flexed to \"cobra position\" (Figure 9c). The transducer is placed in the transverse aspect of the forearm, at the radial head. The \"cobra position\" is convenient for injection at the tendon insertion. The normal DBT image demonstrates homogenous fibrillar hyperechoic eachroture. The DBT tendinopathy goes along with tendon hypoechogenicity, thickening and sometimes also calcifications and increased vascularity. When the tendon is torn and retracted, the recoiled stump may demonstrate the shadowing artifact (Figure 10b) [76]. Furthermore, bicipitoradial bursitis can also be revealed in some patients presenting with anterior elbow pain. Figure 8: Insertion of biceps brachii. The cadaveric specimen shows an anteromedial aspect of the right elbow joint (all specimens were in the same position). (**a,b**) Lacertus fibrosus (bicipital sponeurosis) fans out in the forearm’s fascia and covers the brachial artery. (**c,d**) The proper tendon of the biceps continues to the radial tuberosity. Its position is changing during pronation (**c**) and supination (**d**). Notably, during the supination, the bicipital tendon is moving anteriorly and superficially. (**e**) Area of insertion of the biceps tendon on radial tuberosity—proximally is situated tendon springs off from the long head (LH) and more distally inserting tendon from the short head (SH). Black arrow: medial epicondyle, black arrowhead: bicipital tendon, white asterisk: lateral cutaneous nerve of forearm, black asterisk: median cubital vein, white arrowhead: brachial artery, Bi: biceps brachii muscle, Br: brachialis muscle, BrR: brachioradialis muscle, CFT: common flexor tendon, LF: lacertus fibrosus (aponeurosis of the biceps brachii), PT: pronator teres muscle, RT: radial tuberosity. There is very little evidence regarding distal bicipital tendinopathy interventions and injections. [PERSON] et al. [77] performed a prospective cohort study on 12 patients injecting PRP with US guidance. The study showed significant improvement in pain and functional outcome at 47 months follow up. [PERSON] et al. [78] concluded on a cohort of six patients that a US-guided PRP injection was an effective (regarding improving pain and performance scores) and a safe procedure, but further investigation involving RCT is needed. For the DBT injection, the patient can be positioned supine with the forearm in the \"cobra position\" to access the tendon footprint avoiding the vulnerable adjacent neurovascular structures (Figure 10c) [79]. Potentially vulnerable structures when injecting the DBT are the brachial artery and median nerve, which follow the LF. The course of the lateral cutaneous nerve of the forearm [80] and the median cubital vein should be taken into account laterally from the DBT. As such, the \"cobra position\" provides a potentially safer alternative to injection in the anterior side of the elbow.