Changes in Cervical Posture, Cervical Function, and Neck Pain After Sleeve Gastrectomy

Evaluation of Cervical Posture, Cervical Function, and Neck Pain After Laparoscopic Sleeve Gastrectomy: A Prospective Study

Obesity may contribute to neck pain, altered cervical posture, and impaired cervical function through increased mechanical loading, changes in body alignment, and reduced muscle performance. Although laparoscopic sleeve gastrectomy can produce substantial weight loss, its effects on cervical posture and neck-related function have not been studied comprehensively.

This prospective, single-center study will include approximately 25 adults who are already scheduled to undergo laparoscopic sleeve gastrectomy as part of their routine clinical care. The decision to perform surgery and the surgical procedure itself will not be assigned or modified by the study. Participants will be evaluated before surgery and at 3, 6, and 12 months after surgery.

Study assessments will include neck-related disability, neck pain intensity, quality of life, cervical range of motion, cervical muscle strength and endurance, and cervical joint position sense. Existing preoperative lateral cervical radiographs will be reviewed, and a lateral cervical radiograph will be obtained at the 12-month follow-up to assess cervical spinal alignment.

The primary outcome will be the change in Neck Disability Index scores across the scheduled study assessments. The study aims to determine whether weight loss following laparoscopic sleeve gastrectomy is associated with changes in cervical posture, neck pain, and cervical function.

Obesity may affect the cervical spine through increased mechanical loading, anterior displacement of the body's center of gravity, postural adaptations, systemic inflammation, and impaired cervical muscle function. Although improvements in low back pain and other musculoskeletal symptoms have been reported following bariatric surgery, prospective evidence regarding cervical posture, neck pain, and cervical function after laparoscopic sleeve gastrectomy remains limited.

This is a prospective, single-center study involving adults with obesity who have been scheduled to undergo laparoscopic sleeve gastrectomy based on routine clinical indications. The decision to perform surgery will be made independently of the research protocol. The study will not alter the surgical procedure or assign any experimental drug, treatment, or device.

Approximately 25 participants will be enrolled, with the aim of obtaining at least 20 participants who complete the study follow-up. Assessments will be performed before surgery and at 3, 6, and 12 months after surgery.

Neck-related disability will be assessed using the Neck Disability Index. Neck pain intensity will be measured using a Visual Analog Scale or Numerical Rating Scale, and health-related quality of life will be evaluated using the 12-Item Short Form Health Survey. Cervical range of motion will be measured with an inclinometer. Isometric cervical muscle strength will be assessed using a MicroFET3 handheld dynamometer. Cervical muscle endurance will be evaluated using the craniocervical flexion test with a pressure biofeedback stabilizer, together with cervical flexor and extensor endurance tests. Cervical proprioception will be assessed using a laser-based joint position error test.

Only participants with an existing lateral cervical radiograph obtained before study enrollment for a reason unrelated to the research will be eligible. No additional preoperative cervical radiograph will be obtained solely for the study. At the 12-month follow-up, one lateral cervical radiograph will be obtained to assess cervical sagittal alignment. The C2-C7 Cobb lordosis angle and C2-C7 sagittal vertical axis will be measured using standardized digital measurement methods by the same radiologist.

The primary analysis will evaluate changes in Neck Disability Index scores across the scheduled study visits. Secondary analyses will evaluate changes in neck pain intensity, cervical range of motion, cervical muscle strength, cervical muscle endurance, proprioception, quality of life, and radiographic cervical alignment. Associations between the amount of weight loss and changes in cervical pain, posture, and function will also be explored.

Inclusion Criteria:

• Adults aged 18 to 65 years
• Obesity with a clinical indication for bariatric surgery
• Scheduled to undergo laparoscopic sleeve gastrectomy at Haydarpasa Numune Training and Research Hospital
• Availability of a previously obtained lateral cervical radiograph in the hospital information system or national electronic health record
• Willingness and ability to attend the preoperative and 3-, 6-, and 12-month follow-up assessments
• Provision of written informed consent

Exclusion Criteria:

• Previous cervical spine surgery
• Acute cervical trauma, cervical fracture, or severe cervical deformity
• Diagnosed inflammatory rheumatic disease, such as rheumatoid arthritis or ankylosing spondylitis
• History of a neurological disorder, such as multiple sclerosis, myopathy, or peripheral neuropathy
• Malignancy or advanced systemic disease, such as advanced heart failure or renal failure
• Pregnancy or breastfeeding
• Inability to attend the scheduled follow-up visits