Risk factors for loss of reduction following locked plate fixation of proximal humerus fractures in older adults

Brittany E Haws; Steven A Samborski; Steven Karnyski; Gillian Soles; John T Gorczyca; Gregg T Nicandri; Ilya Voloshin; John P Ketz

doi:10.1016/j.injury.2022.11.043

Risk factors for loss of reduction following locked plate fixation of proximal humerus fractures in older adults

Injury. 2023 Feb;54(2):567-572. doi: 10.1016/j.injury.2022.11.043. Epub 2022 Nov 17.

Authors

Brittany E Haws¹, Steven A Samborski², Steven Karnyski², Gillian Soles³, John T Gorczyca², Gregg T Nicandri², Ilya Voloshin², John P Ketz²

Affiliations

¹ University of Rochester Medical Center, Department of Orthopaedics, 601 Elmwood Avenue, Box 665, Rochester, NY 14642, USA. Electronic address: brittany_haws@urmc.rochester.edu.
² University of Rochester Medical Center, Department of Orthopaedics, 601 Elmwood Avenue, Box 665, Rochester, NY 14642, USA.
³ University of California, Davis, Department of Orthopaedic Surgery, Sacramento, CA, USA.

PMID: 36424218
DOI: 10.1016/j.injury.2022.11.043

Abstract

Purpose: To identify characteristics associated with loss of reduction following open reduction and locked plate fixation (ORIF) of proximal humerus fractures in older adults and determine if loss of reduction affects patient reported outcomes (PROs), range of motion (ROM), and complication rates during the first postoperative year.

Methods: Patients >55 years old who underwent proximal humerus ORIF were reviewed. Patient and fracture characteristics were recorded. Fixation characteristics were measured on the initial postoperative AP radiograph including humeral head height (HHH) relative to the greater tuberosity (GT), head shaft angle (HSA), screw-calcar distance, and screw tip-joint surface distance. Loss of reduction was defined as GT displacement >5 mm or HSA displacement >10° on final follow up radiographs. Patient, fracture, and fixation characteristics were tested for association with loss of reduction. Outcomes including ROM, visual analog scale pain and PROMIS scores, and complication/reoperation rates during the first postoperative year were compared between those with or without loss of reduction.

Results: A total of 79 patients were identified, 23 (29.1%) of which had a loss of reduction. Calcar comminution (relative risk [RR]=2.5, 95% Confidence Interval [CI]=1.3-5.0, p<0.01), HHH <5 mm above GT (RR=2.0, CI=1.0-3.9, p = 0.048), and screw-calcar distance ≥12 mm (RR=2.1, CI=1.1-4.1, p = 0.03) were risk factors for loss of reduction. Upon multivariate analysis, calcar comminution was determined to be an independent risk factor for loss of reduction (RR=2.4, CI=1.2-4.7, p = 0.01). Loss of reduction led to higher complication (44% vs 13%, p<0.01) and reoperation rates (30% vs 7%, p<0.01), and decreased achievement of satisfactory ROM (>90° active forward flexion, 57% vs 82%, p = 0.02) compared to maintained reduction, but similar PROs.

Conclusions: Calcar comminution, decreased HHH, and increased screw-calcar distance are risk factors for loss of reduction following ORIF of proximal humerus fractures. These morphologic and technical factors are important considerations for prolonged reduction maintenance.

Keywords: Calcar screw; Comminution; Complications; Loss of reduction; ORIF; Proximal humerus fracture; Radiographic parameters; Range of motion.

MeSH terms

Aged
Bone Plates
Fracture Fixation, Internal / adverse effects
Fractures, Comminuted* / surgery
Humans
Humeral Fractures* / surgery
Humeral Head
Humerus / surgery
Plastic Surgery Procedures*
Retrospective Studies
Risk Factors
Shoulder Fractures* / diagnostic imaging
Shoulder Fractures* / etiology
Shoulder Fractures* / surgery
Treatment Outcome