Deltoid Muscle Contribution to Shoulder Function

NCT03881462 | Completed DMC

• 1 other identifier: ID 2019-00135
• Study Type: interventional
• Target: 12
• Locations: 1 country
• Sites: 1

Brief Summary

There is only one study in the literature about the quantitative effect of M. deltoideus on the movement of the shoulder. Here, the author described a 35-80% loss of abduction power after selective blockade of the N. axillaris. Gerber, on the other hand, found a loss of abduction force of 73-86% after blockade of the suprascapular nerve. These results are partly contradictory, which is why the investigators think that further investigation is needed. For many questions in the field of shoulder orthopedics, this knowledge would provide an important additional basis for therapeutical decision-making. For example, in the treatment of rotator cuff ruptures but also in the implantation of both inverse and anatomical shoulder prostheses. Also, statements about different outcome prognoses could be made more precisely. Therefore, the investigators would like to perform muscle strength measurements of the deltoid muscle on 12 healthy volunteers on the dominant arm. Abduction, flexion, external rotation and internal rotation Mm. Infraspinatus, Supraspinatus and Subscapularis are tested respectively. The investigators plan to carry out the measurements three times before and after an-anaesthesiological nerve block of the axillary nerve thus inactivating the deltoid muscle (performed exclusively by an anesthesiologist specialized in regional anesthesia). The success of the nerve block is confirmed by needle electromyographies (EMG) by a neurologist specialized in electrophysiology. Using EMG neurogenic pathologies within the tested muscles are also ruled out. In order to exclude relevant rotator cuff pathologies the investigators will perform shoulder radiography in three planes and sonography of the rotator cuff before conducting the experiment described above.

Conditions

Nerve Injury; Nerve Palsy

Keywords

muscle function; rotator cuff

Outcome Measures

Primary Outcomes (1)

• Muscle strength of the rotator cuff

  Strength of abduction, flexion, external rotation and internal rotation in Mm. infraspinatus, supraspinatus and subscapularis respectively measured in Newton before and after blockade of the N. axillaris.

  6 hours

Secondary Outcomes (1)

• Geometric shoulder data

  15 minutes

Study Arms (1)

Axillary nerve block

EXPERIMENTAL

Axillary nerve block is performed in standardized manner and muscle force is measured before and after the block.

Procedure: Axillary nerve block for artificial deltoid muscle palsy

Interventions

Axillary nerve block for artificial deltoid muscle palsy PROCEDURE

Axillary nerve block block (AXNB): The ultrasound probe is placed transversally in the infraclavicular region with the arm in 90° abduction. The brachial plexus and its cords are identified l lateral to the brachial artery. The posterior cord is identified by ultrasound and is blocked - or, if the axillary nerve visible too - the axillary nerve is selectively blocked when it leaves the posterior cord and lies on the subscapular muscle accompanied by the posterior circumflex humeral artery. Using an in-plane technique, a short bevel connected to a nerve stimulator with the setting 0.5 mA current intensity, 0.1 ms impulse duration and 2 Hz impulse frequency for dual guidance, will be advanced until its tip is positioned near the nerve without eliciting motor contractions. After careful negative (for blood) aspiration local anesthetic will be applied until the targeted neuronal structure is surrounded by the injected fluid.

Axillary nerve block

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• American Society of anesthesiologists (ASA) classification I - II, both sexes
• ≥ 18 years old
• \< 65 years old
• Written informed consent as documented by signature

You may not qualify if:

• Severe coagulopathy or intake of anticoagulants
• History of alcohol abuse or the intake of psychotropic drugs
• Pregnancy
• Infection at the injection site or a systemic infection
• Fever of unknown origin
• Motor or sensory abnormalities in the arm
• Any neuromuscular disorders
• significant arthritis or other shoulder joint problems
• Any co-morbidity that interferes with this study (e.g., stroke, pace maker placement, severe ischemia, cardiac disease, etc.)
• inability to provide informed consent or follow simple instructions during experiment
• contraindications for peripheral regional anaesthesia or local an-esthetics used in the study, e.g., known hypersensitivity or allergy to class of drugs or the investigational product

Sponsors & Collaborators

• Balgrist University Hospital: lead

Study Sites (1)

Balgrist University Hospital

Zurich, 8008, Switzerland

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 15, 2019
• First Posted: March 19, 2019
• Study Start: May 1, 2019
• Primary Completion: July 30, 2019
• Study Completion: September 30, 2019
• Last Updated: January 14, 2020

Record last verified: 2019-08

Data Sharing

• IPD Sharing: Will not share

Locations

CH (1)