Correlation between Humpback Deformity and Presence or Absence of Avascular Necrosis and Nonunion in Patients with Scaphoid Waist Fractures

Syed Abidi; Michael Shepel; David Sauder; Prosanta Mondal; Haron Obaid

doi:10.1055/a-2498-0984

Journal of Wrist Surgery, Table of Contents

J Wrist Surg
DOI: 10.1055/a-2498-0984

Scientific Article

Correlation between Humpback Deformity and Presence or Absence of Avascular Necrosis and Nonunion in Patients with Scaphoid Waist Fractures

Authors

Syed Abidi

¹Department of Medical Imaging, Royal University Hospital, Faculty of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
Michael Shepel

¹Department of Medical Imaging, Royal University Hospital, Faculty of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
David Sauder

²Division of Orthopaedic Surgery, Department of Surgery, Royal University Hospital, University of Saskatchewan, Faculty of Medicine, Saskatoon, Saskatchewan, Canada
Prosanta Mondal

³Department of Medical Imaging, Clinical Research Support Unit, Faculty of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
Haron Obaid

¹Department of Medical Imaging, Royal University Hospital, Faculty of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada

Abstract

Background Scaphoid fractures often lead to nonunion and avascular necrosis (AVN). This study investigates the association between humpback deformity (volar angulation malalignment in scaphoid waist fractures) and these complications.

Materials and Methods A retrospective review of radiographs/computed tomography scans from patients with acute scaphoid waist fractures was performed. Union/nonunion status and AVN presence or absence were evaluated based on follow-up radiographs. Humpback deformity was identified using a height-to-length ratio (H/L) > 0.65. Images were assessed by consensus by two musculoskeletal radiologists. Statistical analysis included chi-square/Fisher's exact tests, t-tests, and logistic regression.

Results A total of 84 patients (mean age: 30.4 years) with a mean follow-up for 447.7 days were included. Nonunion occurred in 31%, AVN in 9.5%, and humpback deformity in 54.8%. The nonunion cohort (26 patients) had a higher prevalence of humpback deformity (45.7%). In the AVN cohort (8 patients), 15.2% had a humpback deformity. The humpback cohort (54 patients) showed 46.3% nonunion and 15.2% AVN. Significant association was found between humpback deformity and nonunion (p = 0.001), but not between humpback deformity and AVN (p = 0.067). Logistic regression indicated humpback deformity as a significant predictor of nonunion (p = 0.002).

Conclusion The study revealed a significant association between humpback deformity and nonunion in scaphoid fractures. Although no significant association was found between humpback deformity and AVN, the AVN cohort showed a trend toward higher rates of humpback deformity suggesting that humpback deformity may occur in the context of scaphoid AVN.

Keywords

humpback - scaphoid - fracture - nonunion - avascular necrosis

Full Text

References

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