Differential Plantaris‐Achilles Tendon Motion: A Sonographic and Cadaveric Investigation

Abstract

IV.

Sonographically Guided Plantaris Tendon Release: A Cadaveric Validation Study

“…The PT was identified at the junction of the distal musculotendinous junction of the medial gastrocnemius and soleus muscles as a small, ovoid structure with a tendinous echotexture and a cross‐sectional area of 3‐6 mm 2 . As necessary, sonographic visualization of the PT was facilitated by (1) tilting the transducer to elicit differential anisotropy; (2) scanning the PT more proximally to increase the contrast between the hyperechoic, tendinous PT and the surrounding hypoechoic gastrocnemius and soleus muscles; and/or (3) detecting differential PT‐AT motion during passive ankle dorsiflexion–plantarflexion (Figure ) .…”

“…In this manner, the hook knife transected the PT, the release being indicated by an abrupt loss of resistance and sonographic visualization of a hypoechoic space between the PT and AT. The transected region of the PT was consistently more conspicuous during passive ankle dorsiflexion–plantarflexion (Figure ) . The hook knife was then withdrawn under direct sonographic guidance.…”

“…The plantaris tendon (PT) increasingly has been implicated in the pathogenesis or perpetuation of symptoms in a significant subset of patients presenting with Achilles tendon (AT) pain syndromes, including Achilles tendinopathy . The PT typically lies directly adjacent to the AT, and previous studies have confirmed that the PT and AT possess different biomechanical properties and exhibit differential motion during plantarflexion–dorsiflexion . Consequently, repetitive compressive or shear forces at the PT‐AT interface may pathologically alter the peritendinous tissues within the PT‐AT interface as well as the tendons themselves .…”

“…Previously, PT release and PT removal have been performed in the context of a traditional open surgery . However, the ability to identify the PT, the PT‐AT interface, and the regional neurovascular structures using ultrasound (US) suggests that sonographically guided PT release and sonographically guided PT removal are technically feasible . In theory, compared with sonographically guided PT removal, sonographically guided PT release would be easier to perform and should provide equivalent reduction in PT tension and compressive and shear forces within the PT‐AT interface.…”

The Plantaris Muscle Tendon and Its Relationship with the Achilles Tendinopathy

“…In its initial course, the tendon is located between the gastrocnemius muscle (GM) and soleus muscle (SM) [ 2 – 4 ], and upon leaving this section, in its distal course, the plantaris tendon is typically inserted into the calcaneal tendon [ 1 ]. Despite this classical schema, the course of the PM tendon, and especially its insertion, is characterized by high morphological variability [ 2 , 5 – 9 ]. The plantaris muscle can be double [ 1 , 10 ], and, in rare cases, it can be absent [ 3 , 11 – 13 ].…”