Total knee arthroplasty for distal femoral fractures in osteoporotic bone: a systematic literature review

Purpose
Distal femoral fractures in the elderly are associated with high morbidity and mortality and their incidence is increasing with an ageing population. Management of these fractures has evolved over recent decades and there is now an accepted recognition of the important role that acute arthroplasty may have in treatment of these fractures. Our purpose was to systematically review the evidence available in the literature for arthroplasty as a treatment option for distal femoral fractures.

Methods
This systematic review was conducted in accordance with the PRISMA reporting guidelines. We searched CENTRAL, MEDLINE, EMBASE, and Science Citation Index Expanded (until October 2018) for studies and case series. Furthermore, clinical trial registries were searched for ongoing studies. We included all studies or case series that described total knee arthroplasty for distal femoral fractures irrespective of language, publication status, sample size, or follow-up period due to limited studies available in the literature. Exclusion criteria included single patient case reports, isolated tibia fractures, and periprosthetic fractures. Two authors independently identified trials for inclusion and independently extracted the data. Outcome measures included mortality, peri-operative complications (excluding mortality), anaesthetic time, blood loss, time to mobilisation, length of hospital stay, functional scores, radiological loosening, and revision rate.

Results
Fourteen papers were included for subsequent quantitative and qualitative synthesis incorporating a total of 181 patients. The highest level of evidence identified was a single cohort study (level III), the remaining 13 papers consisted of multi- or single-centre case series (level IV). The mean mortality rate was 3.34% (range 0–10) at 30 days and 18.4% (range 0–42) at 1 year. The mean revision rate was 3.43% (range 0–25) at 1 year. The mean time to mobilisation was 3.90 days (range 2.5–6) with a mean time to discharge from the acute ward being 16.6 days (range 8–33).

Conclusions
Although there is limited evidence in the literature available, our review suggests that there is a role for acute knee arthroplasty in distal femoral fractures. This mode of treatment has satisfactory mortality and revision rates, and may result in faster time to mobilisation and discharge. There is a need for a higher level of evidence to delineate this issue further.