A standardized fluoroscopic method for profiling humeral rotational alignment during intramedullary nailing

Area of Science:

• Orthopedic surgery
• Radiology
• Anatomy

Background:

• Intraoperative assessment of humeral rotation during intramedullary nailing is challenging due to limited available methods.
• Accurate humeral rotation is crucial for optimal functional outcomes after fracture fixation.

Purpose of the Study:

• To propose and validate a standardized fluoroscopic sequence for assessing and restoring humeral rotation during intramedullary nailing.
• To utilize humeral bony anatomy and contralateral limb reference for rotational profiling.

Main Methods:

• A standardized fluoroscopic sequence involving Grashey view of the proximal humerus and lateral view of the elbow was developed.
• Eight paired cadaveric specimens were used to acquire images and compute a corrective index based on angular differences.
• The method was tested by inducing a proximal humerus fracture and setting rotation during intramedullary fixation.

Main Results:

• No statistically significant difference was found between contralateral corrective indices (P = .190).
• High contralateral agreement (rho = 0.957, P = .0002) was observed, with absolute differences ranging from 1° to 8°.
• The contralateral extremity can effectively serve as a template for rotational profiling.

Conclusions:

• The proposed fluoroscopic sequence offers a standardized and reliable method for restoring native humeral rotation.
• The contralateral limb can be used as a valuable reference during intramedullary fixation procedures.