Ultrasound and Somatosensory Median Nerve Evaluation in CRPS I

NCT06978608 | Not Yet Recruiting

• 2 other identifiers: Prot.: 0003733 del 2025Rif CEAVC 28194
• Study Type: observational
• Target: 50
• Locations: 0 countries
• Sites: N/A

Brief Summary

Complex regional pain syndrome (CRPS) is a disorder falling within the sphere of neuropathic pain, characterised by a plethora of symptoms. Regional pain out of proportion to the triggering event is the main presentation, accompanied by allodynia, dysesthesia, thermal asymmetry, trophic changes, oedema and stiffness. Recently, preliminary observational studies have found that the management of patients with CRPS, refractory to pharmacological treatment, by carpal tunnel release may be resolving; This suggests that an irritative carpal tunnel syndrome may be masked as CRPS due to non-specific symptoms and negative electrodiagnostic studies (electromyography-EMG). Classical carpal tunnel syndrome (CTS) is a well-defined clinical condition that can be ascertained by EMG. In contrast, irritative carpal tunnel syndrome has symptoms attributable to CRPS with negative EMG that arises after trauma that required surgery or immobilisation. It is unclear how to define the presence of irritative carpal tunnel syndrome in patients diagnosed as CRPS, and thus how to make a correct diagnosis. Nor is the management of these patients defined. The aim of the research is to analyse all patients with typical symptoms for CRPS to investigate the morphological appearance of the median nerve at the level of the carpal tunnel by means of dynamic ultrasound in comparison with the healthy limb. In addition, in order to quantify the function of the median nerve, investigators will analyse patients by means of a sensory conduction velocity study (SNVC), as common EMG examinations are negative in these patients, while it is possible that the quantification of the sensory part of the nerve may be impaired. In addition, the autonomic component will be investigated by studying the Skin Sudomotor Response (SSR).The hypothesis is that some patients, after an injury that required surgery or immobilisation, develop fibrous soft tissue scarring that creates a kind of space-occupying lesion that compresses the median nerve at the level of the carpal tunnel and reduces its sliding under the transverse ligament of the carpus, a structure that is not elastic and therefore unable to adapt to the volumetric increases within it. The other hypothesis is that the fibrosis and post-traumatic oedema, which is structured, directly involves the median nerve sheath, resulting in irritation. Classical CTS develops due to mechanical trauma, high pressure and ischaemic damage affecting the median nerve and develops as a clinical condition of pure nerve suffering, with symptoms referable to a sensory and motor deficit. In CRPS, on the other hand, allodynia, hyperalgesia, sudomotor and vasomotor abnormalities and trophic changes are all symptoms that may be related, but are not specific, to nerve suffering.

Conditions

CRPS (Complex Regional Pain Syndrome) Type I

Keywords

CRPS; MEDIAN NERVE; CARPAL TUNNEL; SENSORY; ULTRASOUND; SOMATOSENSORY

Outcome Measures

Primary Outcomes (1)

• Number of patients with altered gliding and/or presence of adhesion between the median nerve and the flexor tendons and/or transverse carpal ligament in patients affected by CRPS type I

  Ultrasound examination will be done either to the affected and the contralateral side. The median nerve will be studied in terms of gliding of the nerve , adhesions with the flexor tendons and / or the transverse carpal ligament. The presence of hypertrophy will be addressed by measuring the median nerve thickness.

  Up to 12 months. From date of recruitment until the date of clinical improvement, assessed up to 12 months

Secondary Outcomes (1)

• Number of patients with altered sensory nerve conduction velocity study in patients affected by CRPS type I

  Up to 12 months. From date of recruitment until the date of clinical improvement, assessed up to 12 months

Study Arms (1)

Patients with Budapest Criteria positive for CRPS type I, older than 18 years old

Any specific symptoms will be recorded. Patients will undergo ultrasound examination to analyze on both the healthy and diseased side the morphological aspect of the median nerve at the carpal tunnel level, to address gliding in terms of mm, adhesion between the transverse ligament and flexor tendons. The aim will be to try to define specific predictive morphological patterns relative to the clinical appearance. Sensory nerve conduction velocity (SNCV) of the median-nerve will be evaluated to analyze the somatosensory part of the median nerve and understand the potential use of this as a diagnostic tool.

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

The population will be enrolled at the primary care clinic of the hospital, diagnosed as CRPS type I.

You may qualify if:

• patients diagnosed with CRPS assessed at the AOUC's Hand Surgery and Reconstructive Microsurgery SOD
• Patients aged 18 years and over
• Signature of informed consent for participation in the study and processing of related data

You may not qualify if:

• patients suffering from CRPS type II and therefore with known peripheral nerve injury
• Patients under 18 years of age

Sponsors & Collaborators

• Azienda Ospedaliero-Universitaria Careggi: lead

MeSH Terms

Conditions

Complex Regional Pain Syndromes; Median Neuropathy

Condition Hierarchy (Ancestors)

Autonomic Nervous System Diseases; Nervous System Diseases; Peripheral Nervous System Diseases; Neuromuscular Diseases; Mononeuropathies

Central Study Contacts

Chiara Suardi, MD

CONTACT

+39 3381032276; suardic@aou-careggi.toscana.it

Study Design

• Study Type: observational
• Observational Model: CASE ONLY
• Time Perspective: PROSPECTIVE
• Target Duration: 1 Month
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 23, 2025
• First Posted: May 18, 2025
• Study Start: September 1, 2025
• Primary Completion: September 26, 2025
• Study Completion: February 26, 2026
• Last Updated: May 18, 2025

Record last verified: 2025-04

Data Sharing

• IPD Sharing: Will not share