Muscle Function After Childbirth

Carroll University

Status: Enrolling

Conditions: Force Steadiness; Muscle Fatigue; Muscle Weakness; Postpartum; Nulligravid

Treatments: Diagnostic Test: Active Straight Leg Raise Test; Other: Active Straight Leg Raise Fatigue Task; Diagnostic Test: Ultrasound imaging of abdominal wall; Other: Lower Extremity Strength Testing

Study type: Interventional

Funder types: Other

Identifiers

NCT05073224

2019-0275

A536130 (Other Identifier)

Protocol Version 6/9/2020 (Other Identifier)

Details and patient eligibility

About

This study will evaluate lower extremity and trunk neuromuscular control in 78 nulligravid and postpartum women. Participants will attend two experimental sessions, approximately 1 week apart, to assess neuromuscular function. Physical activity levels will also be assessed.

Full description

Stability of the lumbar spine and pelvis is essential to nearly all activities of daily living, and is achieved primarily by muscular stabilization. Recent studies have shown that postpartum women are more fatigable than nulligravid women during fatiguing tasks with the lumbopelvic stabilizing muscles (23%) and the trunk flexor muscles (52%) at six months postpartum. Postpartum women also demonstrate impaired control of force with the trunk flexor muscles; however, it is unknown if force control during a fatiguing task of the lumbopelvic stabilizing muscles is impaired in postpartum women.

This study has 3 purposes: (1) To quantify limb steadiness during fatiguing exercise of the lumbopelvic stabilizing muscles among nulligravid women and postpartum women; (2) to quantify muscle activity in the trunk, test limb and contralateral limb to provide insight into motor control; and (3) to identify possible factors (inter-recti distance (IRD), physical activity, pain, biopsychosocial factors) that contribute to neuromuscular function (fatigability and force control).

This is a novel, translational study that, for the first time, will quantify lower extremity force control in postpartum women. As this has not been studied before, to the best of the investigators' knowledge, this proposal will be a pilot study to establish means to utilize in power analyses for future studies of larger magnitude. Furthermore, neuromuscular function is not typically assessed clinically in postpartum women, and no tests exist to easily assess fatigability of the lumbopelvic stabilizing muscles in clinic settings. This study will also provide further data to highlight the ASLR Fatigue Task as a possible clinical examination tool and outcome measure to assess fatigability of the lumbopelvic stabilizing muscles.

Enrollment: 78 estimated patients

Sex: Female

Ages: 20 to 35 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Post-partum
• Primiparous (this is their first child)

Exclusion criteria

• multiple gestation
• prescription anti-inflammatory/pain medications that are taken daily
• significant orthopedic conditions that would contraindicate performance of the fatigue task (such as fractures, severe scoliosis, etc)
• cardiovascular & pulmonary disease
• neuromuscular health conditions (such as diabetes, neuropathy, multiple sclerosis, stroke, seizures, etc)
• history of previous abdominal surgery (with the exception of Cesarean delivery)

Nulligravid Women (Controls)

• Women from the surrounding community will also be recruited to serve as controls
• Nulligravid women will meet the same inclusion/exclusion criteria as the postpartum women, with the exception of never having been pregnant

Trial design

Primary purpose: Basic Science

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

---

78 participants in 2 patient groups

Postpartum

Experimental group

Description:

Participants who are six months postpartum will complete 2 experimental sessions, separated by 7-10 days. Participants will complete multiple questionnaires, maximal voluntary contractions of the lower extremity muscles, clinical tests of lumbopelvic neuromuscular control/posterior pelvic pain provocation, and fatiguing lower extremity/trunk muscle exercise. Ultrasound imaging will be performed to measure inter-recti distance. Wireless Electromyography (EMG) sensors will be used to record EMG and limb steadiness (via Inertial Measurement Units (IMU). Physical activity will be measured by questionnaire and accelerometer.

Treatment:

Other: Lower Extremity Strength Testing

Diagnostic Test: Ultrasound imaging of abdominal wall

Other: Active Straight Leg Raise Fatigue Task

Diagnostic Test: Active Straight Leg Raise Test

Nulligravid

Active Comparator group

Description:

Participants who have never been pregnant will complete 2 experimental sessions, separated by 7-10 days. Participants will complete multiple questionnaires, maximal voluntary contractions of the lower extremity muscles, clinical tests of lumbopelvic neuromuscular control/posterior pelvic pain provocation, and fatiguing lower extremity/trunk muscle exercise. Ultrasound imaging will be performed to measure inter-recti distance. Wireless EMG sensors will be used to record EMG and limb steadiness (via IMUs). Physical activity will be measured by questionnaire and accelerometer.

Treatment:

Other: Lower Extremity Strength Testing

Diagnostic Test: Ultrasound imaging of abdominal wall

Other: Active Straight Leg Raise Fatigue Task

Diagnostic Test: Active Straight Leg Raise Test