Background: Patients suffering residual disability after anterior decompression and fusion (ACDF) surgery for cervical disc disease may be prescribed physical activity (PPA) or neck-specific exercises (NSE). Currently, we lack data for the success of either approach. There is also a knowledge-gap concerning the use of internet-based care for chronic neck pain, inclusive of cervical disc disease. The scarcity of these data, and the high proportion of patients with various degrees of incapacity following ACDF, warrants increased efforts to investigate and improve cost-effective rehabilitation.

Objective: To investigate the effectiveness of a structured, internet-based NSE program, versus PPA following ACDF surgery.

Methods: This is a prospective, randomised, experimental, longitudinal multicentre study, that includes 140 patients with residual disability (≥30% on the Neck Disability Index; NDI) following ACDF for radiculopathy due to cervical disc disease. Patient recruitment occurs following attendance at routine clinical appointments, scheduled for 3-months post-surgery. Patients are then randomised to one of two groups (70 patients/group), scheduled for a 3-month treatment of either internet-based NSE or PPA. Questionnaires on background data, pain and discomfort, physical and mental capacity, satisfaction with care, and health and workplace factors are completed, with physical measurements of neck-related function performed by independent test leaders blinded to randomisation. Measurements are performed at inclusion, after the 3-month treatments (end of treatment), and at a 2-year follow-up. Radiography will be completed at the 2-year follow-up. Preoperative data will be collected from the Swedish Spine Registry (Swespine). Data on healthcare consumption, drug use, and sick leave will be requested from the relevant national registers.

The purpose of the study is to investigate whether internet-based, structured NSE, differs from PPA after surgery for cervical disc disease, in relation to function, pain, work capacity, health-related quality of life, satisfaction with care, and cost effectiveness.

The hypothesis is that internet-based NSE will be superior in terms of outcome measures to PPA. This assumption, based on an earlier study of patients with chronic WAD, remains untested for individuals with residual disability following ACDF. The project is expected to lead to improved care, well-being, and patient satisfaction, and, as a result, a reduced societal burden.

Design This is a prospective, randomised, experimental longitudinal multicentre study, with a two-year follow-up. Questionnaires are distributed and physical measurements taken at baseline, at the end of treatment (3 months after enrolment), and after 2 years. Preoperative data is collected from Swespine. Patients are recruited from the surgical unit following regular follow-up visits to the physiotherapist/surgeon at approximately 3 months postoperatively.

Should the study criteria be met, and after the receipt of written and oral informed consent, the patient completes a questionnaire and undergoes physical measurements of neck-related function. The patient is then randomised (computerised block randomisation list compiled by statisticians) to one of two groups for 3 months of treatment with a) internet-based NSE with 3 visits to the physiotherapist or b) PPA with 3 visits to the physiotherapist. In addition, and prior to treatment, patients in both groups are examined by a physiotherapist, in accordance with Swedish law.

The test leader is a physiotherapist at the surgical unit who is not involved in study treatment and is blinded to the randomisation groups. Qualified clinicians will perform X-rays and (potentially) ultrasound registration. Following randomization the results will be put into an opaque envelope that contains the name of the patient and their randomisation group, which is sent to the physiotherapy outpatient care clinic. Questionnaires and tests of physical neck-related function are conducted at baseline (before randomisation), after 3 months (when the treatment ends), and after 2 years. Participant physiotherapists will be provided oral, written, and practical training, and are able to consult project managers at any time. Exercise diaries and the number of care contacts will be recorded for both groups.

Study criteria

Inclusion criteria for each surgical department:

• Record data in Swespine

Inclusion criteria for surgery:

• Cervical disc disease, confirmed by MRI data compatible with clinical findings (neurological examination performed by neck surgeon i.e. neurosurgeon/orthopaedic surgeon) that show nerve root compression in the cervical spine.
• Radiculopathy with pain in one or both arms, with or without sensory and/or motor deficit
• At least 3 months of persistent arm pain

Inclusion criteria for the study:

• ACDF due to cervical disc disease (disc herniation with or without osteophytes, or stenosis caused by osteophytes) in one or two segmental levels
• Age 18-75 years
• Residual disability (approximately) 3 months after surgery (at the re-visit to the surgeon/ physiotherapist at the neurosurgery/ neuroorthopedic clinic) in terms of the Neck Disability Index (NDI ≥30%).
• Access to a computer/tablet/smartphone and the Internet
• Motivated to exercise

Exclusion criteria:

• Myelopathy
• Previous fracture or dislocation of the cervical spine
• Malignancy or benign spinal tumour (e.g. neuromas)
• Spinal infection, ongoing post-operative infection, or previous spondylodiscitis
• Previous cervical spine surgery
• Factors that are contraindicated for study participation or which hinder treatment or follow-up because of systemic disease, physical or mental illness, injury, inconvenience, or postoperative complications.
• Known alcohol/drug abuse
• Lack of ability to write/comprehend/or express oneself in the Swedish language

Intervention Internet-based neck-specific exercise (NSE) Participants will be provided with an explanation and justification for their exercise. Training includes exercises to activate the deep neck muscles (initially daily), continuing with endurance training of the neck and shoulder muscles (3 times/week). Exercise will be tailored to the individual's physical condition, and then scaled up progressively in terms of severity and dose. Participants will undertake three visits to the physiotherapist, where the exercises will be introduced and repeated, in order to establish and control patient comprehension. The exercise is completed with the help of internet support outside of the healthcare system, which can be accessed anywhere, but most probably at home. Photos and videos of the exercises, information, and answers to frequently asked questions are available on the internet-support platform. Patients can contact a physiotherapist by e-mail if necessary. Three visits to the physiotherapist are provided in addition to a mandatory first visit (for new clinical investigations as required by Swedish law). At the end of the treatment period, the patients are encouraged to continue practicing the exercises on their own.

Prescribed physical activity (PPA) The training consists of general, physical, land-based activity (3 times/week). The aim is to find a physical activity outside of the care unit that suits the individual, based on their specific needs and problems. The goal is that the individual should increase their overall level of physical activity, and that that activity is performed as part of a self-care/wellness routine. This may involve activities that can be performed at home, such as walking according to a set schedule, home exercises given by a physiotherapist (not neck-specific training), and aerobic classes etc. To increase compliance, a simple motivational interview is performed before the PPA schedule is provided, which can occur during the same session or at a separate visit, should the physiotherapist and patient prefer. Patients are advised to contact the physiotherapist should their prescribed activity fail to work so that another activity can be identified. Three visits to the physiotherapist are provided in addition to a mandatory first visit (for new clinical investigations as required by Swedish law), with the patient encouraged to continue practicing on their own at the end of the treatment period.

Sample size calculation and statistics Seventy participants per group (i.e. a total of 140 patients) are required. Sample size calculations (conducted by statisticians) are based on the primary outcome measure of Neck Disability Index (NDI). In order to detect a clinically relevant improvement of 10 NDI points, 70 participants per group are needed (assuming 80% power, and a level of significance of 5%). This calculation is based on group differences recorded in previous studies. These include a study in which individuals with chronic whiplash-associated injuries were offered training, as well as a study investigating the benefits of surgery over and above physical therapy for cervical disc disease.

As we lack any studies on rehabilitation for patients with disability after ACDF, this calculation remains hypothetical and our sample size may need to be adjusted after the first 30 people (15/group) have completed the 3-month follow-up. This number can also be adjusted in the event of participants dropping-out, such that at least 70 individuals per group complete the intervention. Data will be analysed using an intention-to-treat approach. Alternative analyses (sub-group analyses) will be carried out where the degree of implementation of treatment (compliance) is taken into account, as well as sex, dizziness, headaches, neurological findings, and the number of segmental levels operated on. Analyses will be performed using parametric or non-parametric statistics, depending on the type of data, in consultation with statisticians as appropriate.

Ultrasound registrations, electromyography, Magnetic Resonance Imaging and kinesthesia may be done on a sub-group of participants to investigate neck muscle structure and function. Interviews may be done on a sub-group of individuals regarding their function, experiences and opinions.

Ethical considerations This study was approved by the Regional Ethical Review Board in Linköping Ref: 2016 / 283-31. The scientists are independent with no commercial ties. Patients are recruited after providing informed consent. Patient data are presented at the group level such that no connection to any individual can be made. All data are anonymised when reported, and subject to the Official Secrets Health Acts. The test leaders are independent and blinded for randomisation. Exercises, both general and neck-specific, have been used extensively in clinical practice and we anticipate no harm from their implementation other than a risk of muscle soreness. Any important harms or unintended effects in each group will be collected by the test leaders. All questionnaires and test materials are encoded by the research group, with code lists stored in locked, fireproof file cabinets, housed at the university in a room with controlled (card-based) access. Only individuals in receipt of a unique website address posted by the researchers can access the program; patients can neither communicate with each other nor with caregivers via the program.

Inclusion Criteria:

Inclusion criteria for each surgical department:

• Record data in Swespine

Inclusion criteria for surgery:

• Cervical disc disease, confirmed by MRI data compatible with clinical findings (neurological examination performed by neck surgeon i.e. neurosurgeon/orthopaedic surgeon) that show nerve root compression in the cervical spine.
• Radiculopathy with pain in one or both arms, with or without sensory and/or motor deficit
• At least 3 months of persistent arm pain

Inclusion criteria for the study:

• ACDF due to cervical disc disease (disc herniation with or without osteophytes, or stenosis caused by osteophytes) in one or two segmental levels
• Aged 18-75 years
• Residual disability (approximately) 3 months after surgery (at the re-visit to the surgeon/ physiotherapist at the neurosurgery/ neuroorthopedic clinic) in terms of the Neck Disability Index (NDI ≥30%).
• Access to a computer/tablet/smartphone and the Internet
• Motivated to exercise

Exclusion Criteria:

Exclusion criteria:

• Myelopathy
• Previous fracture or dislocation of the cervical spine
• Malignancy or benign spinal tumour (e.g. neuromas)
• Spinal infection, ongoing post-operative infection, or previous spondylodiscitis
• Previous cervical spine surgery
• Factors that are contraindicated for study participation or which hinder treatment or follow-up because of systemic disease, physical or mental illness, injury, inconvenience, or postoperative complications.
• Known alcohol/drug abuse
• Lack of ability to write/comprehend/or express oneself in the Swedish language

Single Blind (Outcomes Assessor)