The Effects of TTNS, TTNS Combined With PHUS, and Conventional Therapy With PHUS in the Treatment of PFC.

Eligibility Criteria

Inclusion criteria

Children aged 4 to 14 years.

Diagnosis of functional constipation (FC) established prior to study enrollment. FC is defined according to the Rome IV diagnostic criteria, in the absence of identifiable organic or anatomical causes (e.g., no endocrine, metabolic, anatomical, or neuromuscular dysfunction). No additional diagnostic testing is required for inclusion.

Ability to complete daily diaries and TTNS sessions, either independently or with caregiver support.

Documented failure of conservative medical treatment following at least three months of therapy.

Exclusion criteria

Malformations of the digestive system or rectal anatomical anomalies (e.g., large intestinal atresia or stenosis, Hirschsprung's disease, congenital anorectal malformations).

Neurological or psychiatric conditions (e.g., cerebral palsy, spina bifida, intellectual disability, anorexia nervosa).

Major cognitive impairments.

Metabolic disorders (e.g., diabetes mellitus, diabetes insipidus, scurvy, phenylketonuria).

Endocrine disorders (e.g., hypothyroidism).

Cardiovascular conditions such as heart disease or arrhythmias, or presence of ventriculoperitoneal shunts or cardiac pacemakers, due to potential electrical interference.

History of thoracic or abdominal surgery.

Presence of dermatological lesions in the area of electrode application.

Presence of active electronic implants.

Inclusion criteria

Children aged 4 to 14 years

Clinical diagnosis of functional constipation (FC), with no identifiable organic or anatomical cause (e.g., endocrine, metabolic, anatomical, or neuromuscular dysfunction)

FC diagnosis established according to Rome IV criteria

No additional tests required to confirm eligibility

Ability to complete daily diaries and TTNS sessions (by participant or caregiver)

Failure of conservative medical treatment (including toilet training and laxatives) after at least three months

Exclusion criteria

Malformations of the digestive system and rectal anatomical anomalies (e.g., large intestinal atresia/stenosis, Hirschsprung's disease, congenital anorectal anomalies)

Neurological or psychiatric disorders (e.g., cerebral palsy, spina bifida, intellectual disability, anorexia nervosa)

Major cognitive impairment

Metabolic conditions (e.g., diabetes mellitus, diabetes insipidus, scurvy, phenylketonuria)

Endocrine disorders (e.g., hypothyroidism)

Cardiac conditions (e.g., heart disease, arrhythmias, presence of pacemaker or ventriculoperitoneal shunt) due to possible interference with electrical stimulation

History of thoracic or abdominal surgery

Presence of skin lesions in the area of electrode application

Presence of active electronic implants