While many patients develop dysphagia during or immediately following a medical condition, patients with head and neck cancer (HNC) often develop dysphagia due to late-effect complications months or years after radiation treatment (XRT). Patients post-radiation may swallow adequately immediately following their cancer treatment but then slowly start to complain that they can’t eat their usual diet. This change is often due to increasing scar-like tissue called fibrosis in the radiated area.
It is helpful to understand how and why fibrosis develops. Normal wound healing is governed by a system of cell-signaling mediators that instruct cells to fix damage by making new tissue, which often results in a scar. When the wound is repaired, scar tissue formation stops. For some patients the system that regulates wound healing is damaged during radiation treatment. Since the checks and balances of this system no longer function properly, the cells continue to make scar tissue long-term resulting in increasing stiffness and loss of range of motion (ROM) over time. (Langmore 2010)
Post-radiation fibrosis is likely why dysphagia following XRT is generally characterized by reduced movement throughout the swallowing mechanism (Kotz 2004).
There are 2 primary factors that cause dysfunction with this population:
- The fibrosis results in tethering of swallowing structures such as the hyolaryngeal complex which must elevate, protract and approximate to protect the airway
- The fibrosis restricts movement of muscles which results in disuse atrophy. Muscles must move to stay strong and to get strong, and the slow accumulation of fibrotic tissue causes increasing weakness as there is less movement and subsequently less use of the muscles.
Traditional therapy is ineffective
A recent study published in Head & Neck evaluated the efficacy of swallowing therapy with head and neck cancer patients with and without neuromuscular electrical stimulation (NMES). Therapy consisted of the effortful swallow, the Mendelsohn maneuver, and the super supraglottic swallow which are well-supported in the literature as effective swallowing treatments. The authors concluded that swallowing exercise, regardless of the application of NMES, did not make a statistically significant improvement in functioning with HNC patients.
The authors write “For patients with head and neck cancer with moderate to severe dysphagia caused by radiation therapy, current behavioral therapies are of limited help in reversing long-term dysphagia”, and “…once post irradiation dysphagia is well established, current interventions are limited in reversing the decline in swallow function” (Langmore 2016).
To be effective, swallowing maneuvers such as the effortful swallow, the Mendelsohn, and the super supraglottic swallow are dependent upon a patient’s ability to move their swallowing structures and muscles during the exercise. Since decreased range of motion of the swallowing mechanism is often the primary impairment with HNC patients, it is logical to conclude that the stiffness is what prevents swallowing intervention with this population from being effective.
How can we treat this condition?
The key to successful dysphagia rehabilitation is to address the underlying impairments that are causing the dysfunctions. In an effort to target the impairment of stiffness with HNC patients, myofascial release and manual therapy have become increasingly used components of swallowing treatment.
Myofascial release (MFR) involves a low load, long duration stretch to the myofascial complex to mobilize adhesive tissue to restore optimal length, decrease pain, break up adhesions, and improve function. Fascia is the connective tissue that surrounds muscles, nerves, and organs, and it tightens and hardens over time in response to trauma (such as radiation treatment) (Kelly 2008). Manual therapy (MT) involves skilled passive movement of joints and soft tissue to restore range of motion.
As shown in the chart linked below, MFR/MT can be used to treat multiple aspects of the swallow. Several muscles that cannot be reached directly can be targeted indirectly by stretching the attachment points of those muscles.
MFR/MT Target Area
What evidence do we have for MFR/MT in dysphagia treatment?
Thus far, there has been limited research about the use of MFR/MT in dysphagia treatment. Evidence has primarily consisted of anecdotal reports of positive outcomes from clinicians and patients, but evidence in the form of research trials is emerging.
In 2016, Krisciunas et al investigated the impact of a manual therapy program for HNC patients during radiation treatment. The outcome measures were pain before, during, and after manual therapy and subjective range of motion (ROM) measurements. All the patient felt that MT lessened their pain, and none experienced an increase in pain. ROM improvements were positive but inconsistent. The authors noted that “No change or slight increases in mobility are promising as it is commonly thought that tissue and joint movement decreases in most patients undergoing radiation”. The authors further concluded that “[manual therapy] …. has the potential to reduce localized pain and to mitigate contractile tensions, inflammation, and hypoxia, all of which are implicated in aberrant wound healing, long-term fibrosis, and dysphagia” “…as there are no proven practices or rehabilitative behavioral or pharmacologic interventions capable of mitigating these long-term fibrosis sequel, the potential effect of manual therapy is of great interest”.
In 2017, Lewin et al at MD Anderson Cancer Center researched the potential benefit of an adjunct manual therapy program for patients with a history of HNC an average of 8 years post XRT. All patients improved their cervical ROM and reported functional gains in swallowing, airway, voice, and patient perception.
Where do we go from here?
Myofascial release and manual therapy are promising modalities to help restore range of motion in the swallowing mechanism after HNC treatment to allow for more effective dysphagia treatment. While more details are still needed about the most effective protocol and techniques, expected outcomes, and the potential long-term benefits, there is optimism in the dysphagia field that MFR/MT may be the key element that increases the effectiveness of swallowing therapy with this population.
References
- Kelly J. Myofascial Release and Other Manual Techniques in Dysphagia Management. CIAO Seminars. Continuing education course. January 2008. www.ciaoseminars.com
- Krisciunas GP, Golan H, Marinko LN, Pearson W, Jalisi S, Langmore SE. (2016). A novel manual therapy programme during radiation therapy for head and neck cancer – our clinical experience with five patients. Clin Otolaryngol. Aug; 41(4):425-31
- Kotz T, Costello R, Li Y, Posner M. (2004) Swallowing Dysfunction After Chemoradiation for Advanced Squamous Cell Carcinoma of the Head and Neck. Head and Neck; 26:365-372.
- Langmore SE, Krisciunas GP. (2010) Dysphagia After Radiotherapy for Head and Neck Cancer: Etiology, Clinical Presentation, and Efficacy of Current Treatments. Perspectives on Swallowing and Swallowing Disorders (Dysphagia). June; 19:32-38.
- Langmore, Susan E., et al. (2016) Efficacy of electrical stimulation and exercise for dysphagia in patients with head and neck cancer: A randomized clinical trial.” Head & Neck Apr; 38 Suppl 1:E1221-31
- Lewin J, Woodall H, Porsche C, Barrow M, Hutcheson K. (2017) Integration of Manual Therapy Into a Speech and Swallowing Rehabilitation Program for Head and Neck Cancer. MD Anderson Cancer Center, unpublished.