Minimally Invasive Treatment of Proximal Humerus Fractures With Locking Compression Plate Improves Shoulder Function in Older Patients: Study Protocol for a Prospective Randomized Controlled Trial

Treatment for proximal humerus fractures emphasizes the restoration of shoulder function. Older patients, because of the loss of bodily functions, face enormous difficulties in fracture healing and shoulder functional recovery after sustaining proximal humerus fractures. As previously reported, open reduction with conventional locking plate fixation achieved fair outcomes in 48 cases of proximal humerus fractures in older patients, with an excellent rate of 85.4% according to the Neer classification system. The investigators' clinical experience, however, has shown that the stability of internal fixation is inadequate and must be enhanced. Consequently, the investigators design a microsurgical implantation using a locking compression plate (LCP) to treat proximal humerus fractures in older patients.

In a search of the Web of Science database, the investigators found a randomized controlled trial reported by Wang et al. in which LCP fixation using microsurgical techniques had better outcomes in 20 cases of proximal humerus fractures in older patients. However, the limitation created by the small sample size had profound effects on the reliability of their study.

No relevant articles were retrieved from the Chinese Clinical Trial Register, and only one similar article was found on ClinicalTrials.gov: "Proximal Humerus Fractures: Randomized Study Between Locking Nails and Locking Plates for Neer 2 and 3 Parts" (identifier: NCT01984112). In this clinical trial, Constant-Murley scores were considered the primary outcome, and the follow-up period was 12 months. Importantly, the inclusion criteria and study arms were distinctly different from those in the investigators' study protocol.

The main principle of minimally invasive techniques in orthopedics is to implant a specific bony plate, which is fixed across a transverse fracture, via small incisions of the periosteum, skin, and muscle. These implantation devices include less invasive stabilization systems, dynamic compression plate systems, and LCP systems. Internal fixation with the LCP system involves two completely different fixation techniques and two opposing osteosynthesis principles, namely conventional plate and bridging plate osteosyntheses characterized by direct anatomical reduction. Because of its special design, the LCP can be used as a dynamic compression plate, as a pure internal fixator using locking head screws, or as both combined, thus providing a variety of therapeutic options for surgeons. Moreover, the LCP has good stability and induces less damage to the periosteum; it is therefore beneficial for bone healing and functional recovery. Given these characteristics, the LCP is likely to have stronger stability than the conventional locking plate for internal fixation of fractures. Therefore, the investigators design a study protocol that compares the LCP and conventional locking plate using minimally invasive techniques for internal fixation of proximal humerus fractures in older patients. The investigators hypothesize that the LCP will be more effective than the conventional locking plate in promoting shoulder function recovery with a higher excellent rate according to the Neer classification system for proximal humerus fractures.

Data collection, management, analysis, and open access