Proximal Olecranon Free Flap for Cystic Scaphoid Nonunion: An Anatomical Feasibility Study

Area of Science:

• Orthopedic surgery
• Microsurgery
• Bone grafting techniques

Background:

• Scaphoid nonunion treatment is complex, often requiring vascularized bone grafts.
• Traditional donor sites like the iliac crest and medial femoral condyle have significant drawbacks.
• Investigating alternative vascularized bone sources is crucial for improving patient outcomes.

Purpose of the Study:

• To evaluate the feasibility of using a proximal olecranon osseous free flap for scaphoid nonunion.
• To assess the anatomical characteristics and graft quality of the olecranon flap.
• To determine the proximity of the olecranon flap pedicle to the radial artery for potential in-situ utilization.

Main Methods:

• Harvesting ten proximal olecranon free flaps from cadaveric specimens.
• Measuring pedicle length, diameter, and documenting perforator count and bone graft quality.
• Performing a volar approach to the scaphoid to measure the distance to the radial artery.

Main Results:

• The posterior ulnar recurrent artery (PURA) was consistently identified.
• Median pedicle length was 65 mm, with 1-2 perforators and a median diameter of 2 mm.
• Bone graft quality was predominantly good or moderate; the mean shortest distance from scaphoid to radial artery was 10 mm.

Conclusions:

• The proximal olecranon free flap is a suitable alternative for vascularized bone grafting in scaphoid nonunion.
• This technique avoids the morbidity associated with harvesting bone from separate limbs.
• The olecranon flap presents a promising option for complex fracture repair.