Clinical Efficacy Study of Magnesium-Containing Degradable Polymer Bone Repair Material for Bone-Defect Repair After Extremity Bone Tumor Resection

Overview

This is a single-center prospective randomized open-label non-inferiority clinical trial for adult patients with bone defects after extremity bone tumor resection. This study aims to evaluate the analgesic effect, osteogenic capacity and safety of magnesium-containing degradable polymer bone repair material. Up to 72 eligible patients aged 18-75 years will be enrolled and randomly divided into two groups at a 1:1 ratio. Patients in the experimental group will receive magnesium-containing degradable polymer bone repair material to fill bone defects after tumor removal. Patients in the control group will be implanted with conventional magnesium-free bone repair material. All participants will receive unified surgical anti-infection treatment, pain control, wound management and postoperative rehabilitation.The main study goal is to test whether the pain-relieving effect of the magnesium-containing material is not worse than conventional bone repair material. We will calculate total opioid pain-killer medicine consumption within 3 days, 7 days and 1 month after surgery. Secondary observations include newly-formed bone volume measured by CT three-dimensional reconstruction, surgical site infection rate and local tumor recurrence rate. Patients will complete scheduled follow-up visits at 1-month, 3-month and 6-month after surgery. All unexpected health problems or adverse reactions will be recorded during follow-up.

This investigator-initiated single-center prospective randomized open-label non-inferiority trial plans to recruit 72 adult subjects with bone defects following extremity bone tumor or tumor-like lesion resection. Randomization will be stratified by upper-limb versus lower-limb defect location to balance mechanical load confounding between groups, with 36 subjects allocated to each arm. After standard tumor resection, the experimental group receives implantation of magnesium-containing degradable polymer bone repair material. The control group uses commercially available conventional bone repair material without magnesium. Post-operative standardized care protocols including antibiotic prophylaxis, stepwise analgesia regimen, wound dressing and weight-bearing rehabilitation are identical for both groups. Opioid consumption will be converted to morphine-equivalent dose for primary endpoint analysis, with a pre-specified non-inferiority margin of 9.726 mg morphine equivalent. At 1-, 3- and 6-month follow-ups, thin-slice CT scans are performed for quantitative 3D reconstruction to assess new bone formation volume. Two independent radiology reviewers blinded to group assignment conduct volumetric measurement to reduce assessment bias. Surgical-site infection is defined by combined clinical manifestation, laboratory tests and bacterial culture results. Local tumor recurrence is confirmed by imaging or pathological biopsy. Safety assessments cover material-related adverse reactions, implant-associated complications and surgery-related adverse events.Statistical analyses will test non-inferiority for the primary endpoint. Continuous secondary outcomes will be analyzed using t-test or rank-sum test; categorical variables will adopt Chi-square test or Fisher's exact test. Subgroup analyses for upper-limb and lower-limb subgroups will be performed. Both full-analysis set and per-protocol set will be used for efficacy assessment. This trial follows the Declaration of Helsinki and has obtained institutional ethics committee approval. Written informed consent will be obtained from each participant before enrolment.