The R³ trial is a multicentre cluster randomized controlled trial evaluating an evidence-based, person-centred rehabilitation pathway for patients undergoing lumbar surgery for radicular pain. The pathway includes structured pre-, peri-, and postoperative rehabilitation, early postoperative mobilization, case management, early return-to-work (RTW) guidance, and patient empowerment. Clusters (hospitals) are randomized to implement the R³ pathway (intervention) or continue usual care (control). The primary aim is to determine whether the R³ pathway reduces time to return to work compared with usual care.

Inclusion Criteria:

• Radicular pain (for ≥ 6 weeks prior to screening), with a clear indication for lumbar spinal surgery ((micro)discectomy, decompression and/or fusion), in accordance with the KCE guidelines (when evidence-based multimodal management has not improved pain or function and radiological findings are consistent with clinical symptoms)
• Employed (working or on sick leave for less than 1 year due to spinal pathology)
• Age 18 - 65 years
• Surgery is scheduled within a timeframe of five days to 2 months after the decision for surgery (4 months for fusion)
• For lumbar fusion surgery, the fusion should be restricted to one or two levels
• Able to provide written informed consent, implying that the participant is both physically and cognitively capable of understanding the study information and signing the consent form independently.

Exclusion Criteria:

Patients are not eligible for the trial in case of any of the following criteria:

• Lumbar surgery performed for malignant disease, spinal fracture, infectious spinal disease
• Insufficient knowledge of Dutch or French language to receive education in the recruiting center and to complete the questionnaires (consistent with the language spoken in the recruiting centre)
• Immediate surgery via emergency admission that precludes prehabilitation
• Revision fusion surgery
• Non-residency in Belgium

De-identified individual participant data (IPD) underlying the primary and secondary outcomes will be shared, including demographic variables, surgical characteristics, pain scores, disability measures, quality-of-life outcomes, work-status variables, and follow-up assessments. No identifying data will be shared. Data will be provided in a fully anonymized format in accordance with GDPR and institutional data protection standards.

IPD and supporting documents will become available 12 months after publication of the primary results of the trial. Data will remain available for a minimum of 5 years after publication. Requests can be submitted at any time within this window. After 5 years, continued availability will depend on data storage capacity and institutional policies.

Access will be granted to qualified researchers with a methodologically sound proposal aimed at scientific replication or secondary analyses related to postoperative rehabilitation or return-to-work after lumbar surgery. Requests must include a study protocol and data management plan. Following review and approval by the study team, data will be shared through a secure institutional platform under a data-sharing agreement. Only fully anonymized datasets and approved supporting documents will be accessible.