Journal of Bone & Joint Surgery - American Volume:
1Cedars-Sinai Orthopaedic Center, Los Angeles, California
Inngul C, Blomfeldt R, Ponzer S, Enocson A. Cemented versus uncemented arthroplasty in patients with a displaced fracture of the femoral neck: a randomised controlled trial. Bone Joint J. 2015 Nov;97-B(11):1475-80.
In patients >65 years of age with a displaced femoral neck fracture, should a cemented or uncemented femoral stem be used?
Randomized (allocation concealed), unblinded, controlled trial with 4 and 12 months of follow-up.
A large Swedish trauma center.
141 patients >65 years of age (mean age, 81 years; 70% women) who presented within 48 hours after acute displaced fracture of the femoral neck due to low-energy trauma and had total hip arthroplasty (65 to 79 years of age) or hemiarthroplasty (HA) (≥80 years of age). The exclusion criteria were severe cognitive dysfunction, alcohol or drug abuse, rheumatoid arthritis, osteoarthritis, residence in an institution, or inability to walk independently.
Cemented Exeter stem with gentamicin bone cement (n = 67) or uncemented hydroxyapatite Bimetric stem (n = 74). All procedures were done by experienced orthopaedic surgeons with use of a direct lateral approach; spinal anesthesia was the preferred method. Patients who were 65 to 79 years of age underwent total hip arthroplasty with use of a 32-mm head and a cemented cross-linked polyethylene Marathon cup, and patients who were ≥80 years of age underwent HA with a unipolar head. All patients received perioperative cloxacillin and postoperative low-molecular-weight heparin for 30 days. All patients could bear weight immediately.
Main outcome measures:
Primary outcomes were health-related quality life (EuroQol-5D) and function (Short Musculoskeletal Function Assessment [SMFA] and Harris hip score [HHS]). Secondary outcomes were surgical complications and mortality.
The cemented stem group had better quality of life at 4 and 12 months (p ≤ 0.001), better HHS scores at 4 months (78 vs. 71; p = 0.004) but not at 12 months, better SMFA dysfunction scores at 4 and 12 months (p ≤ 0.007), and better SMFA bother scores at 12 months (p = 0.007). No patient in the cemented stem group and 9 patients in the uncemented stem group had an intraoperative femoral fracture. The groups did not differ in terms of mortality at 4 or 12 months.
In patients >65 years of age with a displaced femoral neck fracture, treatment with a cemented femoral stem resulted in better quality of life and hip function at 4 and 12 months compared with treatment with an uncemented stem.
Source of funding:
For correspondence: Dr. C. Inngul, Department of Clinical Science and Education, Södersjukhuset, Stockholm, Sweden. E-mail address: email@example.com
The trial by Inngul and colleagues supports the use of a cemented femoral stem for the treatment of a displaced femoral neck fracture. The trial was small; although originally designed as 2 separate trials (one focusing on total hip arthroplasty in patients 65 to 79 years of age and one focusing on HA in patients ≥80 years of age), the 2 trials were pooled because of slow recruitment. One might argue that a healthy, independent 66-year-old patient is very different from an 86-year-old patient who lives with caregiver support.
Because of slow recruitment, the authors combined the 2 trials to regain power to detect differences in outcomes. However, confidence intervals were not provided for the effect estimates. Although there was no significant difference in mortality at 4 or 12 months, 1 intraoperative death occurred in the cemented stem group; thus, the finding of no difference may be due to a type-2 error. There were 9 femoral fractures in the uncemented stem group, but no details were provided about the ages of the patients in whom the fractures occurred. Were all of these patients >80 years of age? Mean blood loss was not significantly different between the cemented and uncemented stem groups, but the standard deviations (SDs) were almost as large as the means (297 ± 202 mL and 341 ± 259 mL, respectively). No information was provided about mean intraoperative blood loss in the total hip arthroplasty and HA groups. In addition, the authors did not comment on the discrepancy in the proportion of patients with a Dorr type-C femur (61% in the cemented stem group and 24% in the uncemented stem group, based on available radiographs). This imbalance is unusual in a randomized trial but may have been due to the small sample size.
The trial was well designed, but a larger sample would have provided more definitive evidence and allowed for a meaningful analysis of patients by age group (<80 and ≥80 years of age) and by treatment (total hip arthroplasty and HA).
Disclosure: The author indicated that no external funding was received for any aspect of this work. The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article.