The pain that does not end with surgery: A new study led by researchers from Assuta Medical Centers, in collaboration with Ben-Gurion University, points to new factors that may explain why many women suffer from pain, restricted movement, and impaired arm function following breast cancer surgery. According to the findings, upper limb morbidity does not depend solely on the type of surgery or the extent of surgical intervention, but is also influenced by sleep quality, emotional distress, underlying medical conditions, and treatments given to the patient.
The study, published in the scientific journal The Breast, included data analysis of 1,602 women who underwent breast cancer surgery. The women were examined over a period of up to 36 months following surgery. Researchers combined data from three prospective cohort studies conducted in Israel in 2023 and 2024.
The data showed that 61% of women included in the study suffered from some form of upper limb morbidity after surgery. Morbidity included arm pain, restricted range of motion, functional impairment, or lymphedema – a condition in which lymphatic fluid accumulates in tissues, causing swelling, heaviness, and potential mobility impairment.
Researchers examined a wide range of factors that may affect the risk of arm morbidity following treatment. Alongside known medical factors, including chemotherapy, radiation therapy, underlying conditions, and post-surgical complications, emotional and behavioral factors were found to make a particularly significant contribution.
Sleep and emotional health play a key role in recovery
One of the most prominent findings was the link between insomnia and upper limb morbidity. Women who suffered from insomnia faced nearly three times higher risk of developing pain, restricted movement, functional impairment, or lymphedema after treatment. Emotional distress was also found to be an independent factor that increased risk, even after researchers controlled for other medical and surgical factors.
Exposure to chemotherapy, underlying medical conditions, and post-surgical complications were also linked to increased risk. Conversely, after controlling for numerous variables, factors previously considered particularly central – such as surgery type, extent of lymph node surgery, or breast reconstruction – were found to have a more limited independent association with morbidity compared to broader factors such as sleep disorders, emotional distress, and comorbidities.
The findings challenge the notion that arm impairment following breast cancer treatment is primarily a direct result of surgery, lymph node removal, or radiation. According to the study, the recovery process is more complex and is influenced by a combination of the patient's medical condition, treatments received, mental health, sleep quality, and resources available during the recovery period.
Advanced machine learning models were also used as part of the study. Researchers found that the models improved the ability to predict which women are at risk for upper limb morbidity compared to the basic screening tool. The use of these models may enable more precise risk assessment in early post-surgery stages in the future.
The practical significance of the findings is that assessing a woman's condition following breast cancer surgery should be broader and not based solely on the type of surgery or oncological treatment. Gathering information on sleep quality, emotional distress, functional level, physical activity, and underlying health conditions may help medical teams identify earlier those women who require close rehabilitation follow-up, physiotherapy, or personalized intervention.
Prof. Merav Ben-David, head of the Oncology Department at Assuta Medical Centers, said: "A wide variety of surgeries to cure breast cancer are performed at Assuta Ramat Hachayal. The women operated on undergo a variety of treatments and return to full lives with complete recovery, which is why it is important to us to maintain excellent quality of life going forward."
According to her: "The ability to predict who will need fast rehabilitation and physiotherapy after surgery in order to return to normal activity is essential and enables women to maintain a high level of functioning." She added that attention from the treating medical team regarding sleep disturbances, lack of personal and family resources, and comorbidities may improve multidisciplinary care for women following breast cancer surgery.