Role of Central Intramedullary Fibular Strut Autograft Augmented Fixation in Proximal Humerus Fractures for Calcar...

Proximal humerus fractures with medial calcar disruption present a surgical challenge. Screw cut-out and varus collapse are common complications following fixation. Augmentation of fixation using intramedullary fibular autograft with medialization along the calcar adequately restores the medial column, which is a well-described technique in the literature. We undertook this study to evaluate the results of central intramedullary placement of fibular autograft without medialization.

We conducted this prospective study with 15 patients over 2 years with a minimum follow-up of 1 year. The inclusion criteria included all patients greater than 18 years of age with a fracture of the proximal humerus but with medial calcar disruption (>2 mm cortical discontinuity in anteroposterior or axillary views, or absence of continuity between calcar and proximal fragment in comminuted fracture) patterns. All the patients were operated upon using deltopectoral approach with a proximal humerus locking plate with central placement of intramedullary fibular strut autograft without medialization. The patients were followed up at six weeks, three months, six months, and one year. At each follow-up, X-rays were done and the shoulder range of motion was assessed. Disabilities of Arm, Shoulder and Hand (DASH) score and Visual Analog Score (VAS) were also recorded.

All fractures had united by (mean) 6.5 months. None of the patients reported with avascular necrosis, screw cut-out, or varus collapse at the final follow-up. One patient had a deep infection which required debridement, plate removal, but the fibular graft was retained. There were no fibular autograft donor-site complications. Humeral head height and humerus neck shaft angle were well maintained (p < 0.05). The DASH and VAS scores decreased significantly (p < 0.05) over serial follow-ups. The DASH (Mean±Standard Deviation) score was 27.27±5.80 and the VAS score was 1.33±0.98 at the final follow-up (1 year) (p < 0.05). There were significant improvements (p < 0.05) in the shoulder range of motion at the final follow-up (Mean±Standard Deviation) flexion 138.6±11.7 degrees, extension 40.3±7.7 degrees, abduction 135.3±9.7 degrees, adduction 38.4±5.7 degrees, internal rotation 50.6±9.5 degrees and external rotation 42.0±6.9 degrees.

We admit the limitations of our study, namely small sample size, lack of control group (locking plate alone or locking plate with medialized fibular graft), and lack of biomechanical data, but we can conclude that central intramedullary placement provides satisfactory medial support in this small series to maintain a valgus reduction. Larger comparative studies are required before asserting equivalence with medialized graft placement.