Musculus rhomboideus thoracis
The thoracic rhomboid is a deep muscle connecting the thoracic spine to the scapula. It originates from the spinous processes of T2-T7 via the nuchal ligament and inserts on the medial surface of the scapular cartilage. Its actions are to elevate and stabilize the scapula against the trunk. It is innervated by ventral branches of cervical and thoracic spinal nerves (roughly C6-T1). It is part of the synsarcosis (muscular sling) suspending the trunk between the forelimbs.
Origin: Spinous processes of T2-T7 via the nuchal ligament
Insertion: Medial surface of the scapular cartilage
Action: Elevates and stabilizes the scapula against the trunk
Innervation: Ventral branches of cervical and thoracic spinal nerves (C6-T1)
Isolated injury is uncommon. Relevant in evaluations of scapular stability and after trauma to the withers or cranial thoracic region.
## Overview A saddle with tree points that are too narrow concentrates pressure on the withers, causing bruising, spasm, and pain. Horses flinch when saddled, show restricted forelimb protraction, de
## Overview Forelimb compensation refers to secondary muscle soreness and asymmetry around the withers that develops when a horse alters posture or gait to protect a primary forelimb lameness. The si
Persistent scapular asymmetry or reduced shoulder mobility after trauma should be evaluated. Correct saddle fit helps protect the region.
## Overview A saddle with tree points that are too narrow concentrates pressure on the withers, causing bruising, spasm, and pain. Horses flinch when saddled, show restricted forelimb protraction, develop muscle atrophy at the withers, and have a shortened front stride. ## Causes Saddle tree too narrow for the horse’s withers. ## Diagnosis Palpation, sweat patterns, and professional saddle assessment. ## Treatment Refit or replace the saddle. Allow the tissues to heal. Physiotherapy for muscle spasm. ## Recovery and Prognosis Excellent once pressure is removed. ## Prevention Correct saddle fitting. Signs include: pain on palpation of the wither region; flinching when saddled; restricted forelimb protraction; muscle atrophy at the withers; shortened front stride
## Overview Forelimb compensation refers to secondary muscle soreness and asymmetry around the withers that develops when a horse alters posture or gait to protect a primary forelimb lameness. The signs often resolve once the original lameness is treated. ## Causes Weight redistribution and altered muscle use secondary to foot, tendon, or joint pain in the forelimb. ## Diagnosis Identification of a primary lameness plus unilateral withers or shoulder-girdle soreness that improves after the primary problem is addressed. ## Treatment Treat the primary lameness. Supportive physiotherapy and anti-inflammatories for the secondary muscle pain. ## Recovery and Prognosis Good once the inciting lameness is resolved. ## Prevention Early treatment of forelimb lameness. Signs include: unilateral muscle soreness near the withers; asymmetric wither development; sensitivity that resolves when primary lameness is treated
Isolated injury is uncommon. Relevant in evaluations of scapular stability and after trauma to the withers or cranial thoracic region.
Persistent scapular asymmetry or reduced shoulder mobility after trauma should be evaluated. Correct saddle fit helps protect the region.
See the Thoracic Rhomboid on our interactive 3D horse model. Open 3D Model