Interfascial ultrasound-guided infiltration of the lower trapezius and spinal extensor muscles

Ultrasound-guided interfascial injections between the lower trapezius and spinal extensor muscles aim to provide symptomatic relief for patients with chronic myofascial pain. As we discussed in previous articles, these injections can be performed with local anesthetics and corticosteroids in cases of persistent pain that does not improve with conservative measures or in combination with rehabilitation.

Ultrasound-guided injections of an interfascial space release potential adhesions between the muscles in question. By using a local anesthetic, it blocks the nerves and nerve endings that circulate in this interfascial plane, providing symptomatic relief from chronic pain and improving inflammation and muscle function.

Again, we must remember the importance of the connective tissue that covers and limits the muscles (fascia), through which the nerves, blood vessels, and small nerve endings responsible for pain circulate.

El empleo de la ecografía nos dota de un arma eficaz, segura y precisa para evitar aquellas estructuras nobles que no han de ser lesionadas en el procedimiento médico. En la figura 1 observamos la importancia de los puntos gatillo del músculo trapecio inferior y el patrón del dolor referido según el punto gatillo observado.

Figure 1: Trigger points (X) and referred pain of the lower trapezius muscle.
 

The importance of the lower trapezius in scapular mobility is undeniable, as it is involved in elevating the shoulder, assisting the serratus anterior, and controlling arm drop during descent.

Ultrasound-guided interfascial injections at the lower trapezius-extensor level of the spine can reduce inflammation and pain, and improve muscle function, and indirectly improve scapular mobility impairment caused by pain.

Ultrasound-guided interfascial injections of the lower trapezius and rectus spinae (see Figure 2) are indicated for chronic myofascial pain that may be the cause of reduced scapular superior rotation and secondary loss of shoulder function. Inhibition of the lower trapezius is often related to scapular dyskinesis, which in turn can be a precursor to shoulder pain.

Chronic pain in both muscles can be due to postural causes, overload, overuse, repetitive movements, physical exertion, or myofascial injury.

Figure 2: Needle access to the interfascial space between the lower trapezius and erector spinae (white line).

Both muscles are common sources of acute and chronic pain in clinical practice. The first line of treatment is physical therapy with stretching combined with myofascial release techniques, deep gliding massages with friction, etc.

Patients who fail to improve with various rehabilitation treatments are candidates for interfascial ultrasound-guided injections.