Evaluation of Latissimus Dorsi Muscle During Isometric Exercises in Scoliosis

Scoliosis is a complex three-dimensional deformity of the spine, of uncertain etiology, but multifactorial and mainly involves characteristic changes in the sagittal plane also, changes in the coronal plane, and varying degrees of vertebral rotation in the axial plane. The prevalence of scoliosis in the general population worldwide is 0.93% to 12%. In the last few decades, different factors affecting the prevalence of scoliosis have been identified, such as gender, age, skeletal maturity, body mass index, family history, and ethnicity. Discussions about the causes of scoliosis are still ongoing, whether it is only genetic or due to factors such as exercise and environment. In recent studies, pre-scoliotic changes are also examined. Some risk factors for the development of scoliosis include gender, age, ethnicity, and family history. Since apical rotation, gibbosity, and costa vertebral angle are considered to be associated with rotation in the literature, these parameters have been defined as risk factors for the progression of the curve.

Cobb angle, Risser sign, and chronological age are taken as the basis to determine the progression of scoliosis. The main diagnostic criterion for scoliosis with varying degrees of vertebral axial rotation is spinal curvature greater than or equal to 10° in the coronal plane on a flat anteroposterior X-ray image. The Adam's Test is universally accepted as the primary means of diagnosing scoliosis. The Adam's test shows the rotational component of scoliosis. The onset, progression, and treatment of scoliosis include biomechanical changes and parameters. Structural changes, biomechanical changes, and asymmetries develop between the concave and convex sides. Some studies show that paravertebral muscle asymmetry is caused by the curvature of the spine. Trapeze, LD (latissimus dorsi), and erector spine muscles are examples of paravertebral muscles affected.

The LD is a large, smooth muscle lining the lower posterior rib cage and is one of the paravertebral muscles most commonly affected in scoliosis. LD has shoulder, lumbar spine, and sacroiliac joint connections. Scapula, rib cage, and lumbar region deformities seen in scoliosis can be explained by LD. This may make LD a significant cause of scoliosis. In addition, dynamic and static muscle activation rates of LD should be considered in the diagnosis of scoliosis.

Although guidelines have been established for treatments in the direction of spinal curvature, the choice of treatment type is often subjective and based on clinicians' experience. In the treatment of scoliosis, treatment methods such as physiotherapeutic scoliosis-specific exercise (PSSE), corset, surgery, EMG biofeedback, and neuromuscular training are used. Asymmetry observed in the paraspinal muscles of individuals with scoliosis made us think that we should analyze the LD muscular activations in more detail. The aim of our study is to examine the muscle activation values of the lateral and medial parts of the LD during isometric exercises.

Inclusion criteria

Scoliosis group

• aged 18-35,
• Risser stage >4,
• Cobb angle of 10-35°,
• range of 18 <BMI <25,
• volunteered to participate

Healthy group

• aged 18-35,
• range of 18 <BMI <25,
• volunteered to participate

Exclusion criteria

• with a history of neuromuscular, cardiovascular, pulmonary, vestibular, or rheumatological diseases,
• had previously received any surgical or conservative treatment of the spine,
• exercised regularly