The soleus muscle
Last reviewed: 20.11.2021
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The soleus muscle is m. Soleus
Is the main flexor of the foot, and also helps supination of the foot.
Beginning: head and posterior surface Fibula, Tibia, Arcus tendineus m. Solei
Attachment: Tuber calcanei
Innervation: spinal nerves L4-S2 - sacral plexus - n. Tibialis
Palpation:
- The trigger zone is localized 2-3 cm distal to the end of the muscle abdomen of the gastrocnemius muscle and slightly medial to the midline.
- Trigger zone is formed on the lateral surface of the calyx more proximally than in point (a) (a rarer variant).
- The trigger zone is slightly proximal and lateral than in (a) (an even more rare option)
Trigger zone soleus muscle can be detected using planar palpation, and the distal trigger zones also by means of a pincer. The patient either kneels on a chair, or lies on his side. The knee should be bent so that the soleus muscle relaxes. In the first and third cases, the trigger zones can be examined in the patient's position on the side with the back to the investigator; the injured shin lies on the table. The pain from these trigger zones is located deep beneath the aponeurosis of the Achilles tendon. The compaction sites are palpated with the help of a pincer-like palpation: the muscle is held between the thumb and the rest, and then rolled between them. These compaction areas can easily be missed when inept palpation. The researcher must penetrate the fingers distally from the gastrocnemius muscle and from behind the underlying tibial and fibular bones, raise the muscle and examine its back surface, rolling the muscle fibers under the fingers, while the thumb should remain in place. Or palpation is carried out with the thumb, and the remaining fingers are held in place. The medial and lateral sides of the muscle may require separate studies.
In the second case, the trigger zones usually exist together with the more distal trigger zones of the soleus muscle. It is important to investigate the area of localization of trigger zones by plane palpation against the underlying bone, with the knee should be bent by 90 °, so that the soleus muscle is relaxed. This reduces the likelihood that trigger zones of the soleus muscle will accept trigger zones of the more superficial gastrocnemius muscle. Only the trigger zones of the gastrocnemius muscle increase its sensitivity to palpation when the angle of flexion of the knee changes in the direction of extension. When studying in the position of kneeling with a slight extension of the foot, the researcher can obtain an additional stretch of soleus muscle, which increases the sensitivity of its trigger zones.
Reflected pain: trigger zones cause pain:
- on the posterior surface and on the plantar part of the heel, as well as in the distal part of the Achilles tendon;
- diffuse pain in the upper half of the calf;
- deep pain in the ipsilateral sacroiliac joint in a region of about 2.5 cm in diameter, less commonly, less intense pain at the site of its localization and above the posterior and plantar surface of the heel.