Sir—We read with interest the article by Yli-Kynyy et al. (2014) on the use of cemented versus cementless hemiarthroplasty in the treatment of femoral neck fractures. However, we would like to know some aspects of the study which would be of help to orthopedic surgeons.
The authors found an increased mortality rate directly related to the use of cemented hemiarthroplasty and fat embolus syndrome in their study. However, the mortality after hip fracture is multifactorial including operative delay (Ratcliff et al. Citation2008). In the present study the time of the fracture event and start of the surgical intervention were not presented.
The second point is that hip fracture is associated with a substantial increase in mortality with co-existing chronic renal failure (Karaeminogulları et al. Citation2007). We found no information about the co-existence of renal disease.
Teero Yli-Kyyny
Department of Orthopedics, Traumatology and Hand Surgery, Kuopio University Hospital and University of Eastern Finland, Kuopio, Finland
Correspondence: [email protected]
Sir—We appreciate your interest towards our article about the hip hemiarthroplasty (Yli-Kynyy et al. 2014). It is true that mortality during the first 4 days after hip fracture surgery was higher among patients treated with cemented hemiarthroplasty. It is also true that we suggested the cement implantation syndrome as a possible cause for this. However, we would like to stress that we did not suggest it to be the only cause for the difference noted.
The postoperative mortality of hip fracture patients is higher when the delay to operation is longer (Bottle and Aylin Citation2006). However, it is less clear whether a direct relationship exists after adjustment for patients’ comorbidities (Sund 2006) In other words, it is likely that patients with more serious health issues (and at higher risk of death) are more likely to be delayed. It also has been found out in another study from the PERFECT database that operative delay itself may not be an independent predictor of postoperative mortality (Sund and Liski Citation2005).
As we did not report analyses that had been adjusted for the operative delay or chronic renal failure in our article, we will do it here. Prevalence of chronic renal failure was 7.8% among uncemented and 6.3% among cemented patients (p < 0.001). We also found out, as expected, that prolonged operative delay was associated with higher mortality. However, it did not affect the mortality difference between cemented and uncemented hemiarthroplasty. Similarly, the inclusion of renal disease as a covariate did not affect the difference in mortality between cemented and uncemented hemiarthroplasty.
In other words, our conclusions remain the same after these additional adjustments.
- Bottle A, Aylin P. Mortality associated with delay in operation after hip fracture: observational study. BMJ 2006; 332: 947-51.
- Karaeminogulları O, Demirörs E, Sahin O, et al.Analysis of outcomes for surgically treated hip fractures in patients undergoing chronic hemodialysis. J Bone Joint Surg (Am) 2007; 89 (2): 324-31.
- Ratcliff TA, Henderson WG, Stoner JT, et al. Patient risk factors, operative care, and outcomes among older community-dwelling male veterans with hip fracture. J Bone Joint Surg (Am) 2008; 90 (1): 34-42.
- Sund R. A rapid response to the article of Bottle A and Aylin P. ”Mortality associated with delay in operation after hip fracture: observational study”. BMJ Epub only. original article published in BMJ 2006; 332: 947-51.
- Sund R, Liski A. Quality effects of operative delay on mortality in hip fracture treatment. Qual Saf Health Care 2005; 14: 371-7.
- Yli-Kyyny T, Sund R, Heinänen M, Venesmaa P, Kröger H. Cemented or uncemented hemiarthroplasty for the treatment of femoral neck fractures? A Finnish database study of 25,174 patients. Acta Orthop 2014; 85: 49-53.