Cement technique correlates with tuberosity healing in hemiarthroplasty for proximal humeral fracture

Abstract

Background: Tuberosity healing correlates with clinical outcomes after hemiarthroplasty for 4-part proximal humeral fractures (4PHFs). We seek to examine variables that affect tuberosity healing.

Methods: This was a retrospective comparative study. At 1 year postoperatively, patients who underwent hemiarthroplasty for 4PHFs were divided into 2 groups: those with anatomically healed tuberosities and those with tuberosity nonunion. The primary variables included time between injury and surgery, prosthesis fenestration, cement mantle classification, and both vertical and horizontal tuberosity reduction. Secondary demographic factors included age, gender, osteoporosis status, diabetes status, and smoking status.

Results: There were 84 individuals who met the inclusion criteria: 37 (44%) had anatomically healed tuberosities, and 47 (56%) did not. Individuals with anatomic healing had cement near or under the tuberosities 32% of the time, whereas individuals with nonunion or resorption had cement near the tuberosities 66% of the time (P = .002). There was no association between tuberosity healing and fenestration of the humeral stem (P = .84). Anatomic reduction between tuberosities was associated with healing (P <.001), whereas greater tuberosity-to-head height was not (P = .25). There were no significant differences in age, osteoporosis status, smoking status, diabetes status, or time to surgery between groups. Male patients had nearly double the rate of healing (P = .03).

Discussion and conclusion: The classification and effect of cement technique on tuberosity healing have not previously been described. We suggest limiting cementation to a minimum of 5 mm below the level of the tuberosity fracture. The ideal candidate for hemiarthroplasty for a 4PHF is a male patient with anatomic tuberosity reduction and limited use of cement.

Keywords: Proximal humeral fracture; bone cement; fracture healing; hemiarthroplasty; patient comorbidities; surgical technique.