Lymphedema Severity on Shoulder Joint Function and Muscle Activation Patterns in Breast Cancer Survivors

Study Overview
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Brief Summary
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Breast cancer-related lymphedema (BCRL) is a common complication affecting the upper extremity following breast cancer treatment. This study aims to investigate the relationship between lymphedema severity and shoulder joint function and muscle activation patterns in breast cancer survivors.

Official Title
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The Impact of Lymphedema Severity on Shoulder Joint Function and Muscle Activation Patterns in Breast Cancer Survivors: A Cross-Sectional Study

Conditions
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Breast Cancer, Breast Cancer Female

Intervention / Treatment
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* Other: Lymphedema severity stratification


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Female Adults (18 years or older) Diagnosis of breast cancer-related lymphedema for a minimum of 3 months No current evidence of active cancer Able to provide informed consent Exclusion Criteria: Pre-existing musculoskeletal conditions affecting the upper extremities (e.g. adhesive capsulitis, rotator cuff tear) Previous upper extremity surgery Physical inability to perform the required physical movements and assessments

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Mild lymphedema (stage 1)<br>International Society of Lymphology lymphedema severity stage 1, characterized by swelling with pitting, normal skin and tissue turgor. Participants assigned to this group will have mild swelling and tightness of the arm. | Other: Lymphedema severity stratification<br>* Participants will be stratified into one of three lymphedema severity groups based on the International Society of Lymphology lymphedema severity staging: Mild (stage 1): swelling with pitting; normal skin and tissue turgor Moderate (stage 2): swelling with pitting; dermal thickening; skin changes without distortional warty-overgrowth Severe (stage 3): swelling with non-pitting; warty overgrowth or elephantiasis folds<br>|
| Moderate lymphedema (stage 2)<br>International Society of Lymphology lymphedema severity stage 2, characterized by swelling with pitting as well as skin and tissue changes such as dermal thickening. Participants assigned to this group will have moderate swelling and tightness of the arm as well as skin changes without distortional warty-overgrowth or elephantiasis folds. | Other: Lymphedema severity stratification<br>* Participants will be stratified into one of three lymphedema severity groups based on the International Society of Lymphology lymphedema severity staging: Mild (stage 1): swelling with pitting; normal skin and tissue turgor Moderate (stage 2): swelling with pitting; dermal thickening; skin changes without distortional warty-overgrowth Severe (stage 3): swelling with non-pitting; warty overgrowth or elephantiasis folds<br>|
| Severe lymphedema (stage 3)<br>International Society of Lymphology lymphedema severity stage 3, characterized by swelling with non-pitting, and warty-overgrowth or elephantiasis folds of skin. Participants assigned to this group will have severe swelling and tightness of the arm with warty overgrowth of skin. | Other: Lymphedema severity stratification<br>* Participants will be stratified into one of three lymphedema severity groups based on the International Society of Lymphology lymphedema severity staging: Mild (stage 1): swelling with pitting; normal skin and tissue turgor Moderate (stage 2): swelling with pitting; dermal thickening; skin changes without distortional warty-overgrowth Severe (stage 3): swelling with non-pitting; warty overgrowth or elephantiasis folds<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Shoulder joint mobility | shoulder flexion, abduction, external rotation and extension range of motion measured using a digital inclinometer. | baseline | 
| Muscle activation patterns (Amplitude) | Surface EMG recording of muscle activation patterns (amplitude) of the biceps brachii, anterior/middle/posterior deltoid, pectoralis major and latissimus dorsi during shoulder elevation. Amplitude will be reported in units of microvolts (µV) | baseline | 
| Muscle activation patterns (Timing) | Surface EMG recording of muscle activation patterns (timing) of the biceps brachii, anterior/middle/posterior deltoid, pectoralis major and latissimus dorsi during shoulder elevation. Timing will be reported in units of milliseconds (ms). | baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Shoulder flexors strength | Maximal shoulder flexor abductor strength measured as force production (N) using a handheld dynamometer. The average of 3 trials for each muscle group will be calculated. | baseline | 
| Shoulder abductor strength | Maximal shoulder abductor strength measured as force production (N) using a handheld dynamometer. The average of 3 trials for each muscle group will be calculated. | baseline | 
| Self-reported upper extremity function | The Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, developed by the Institute for Work and Health, is used to measure patient-reported functional outcomes. The DASH questionnaire consists of 30 questions regarding limitations to complete physical activities due to upper extremity pain/impairment. Participants will be asked to respond to each question based on their experiences over the preceding week according to a 5-point Likert scale ranging from 1 (no difficulty) to 5 (unable to do). Responses will be scored out of 5 and averaged to produce a score out of 100 with higher scores representing greater disability. | baseline |