Interventions for treating fractures of the distal femur in adults.

BACKGROUND Fractures of the distal femur (the part of the thigh bone nearest the knee) are a considerable cause of morbidity. Various different surgical and non-surgical treatments have been used in the management of these injuries but the best treatment remains controversial. OBJECTIVES To assess the effects (benefits and harms) of interventions for treating fractures of the distal femur in adults. SEARCH METHODS We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (9 September 2014); the Cochrane Central Register of Controlled Trials (The Cochrane Library, 2014, Issue 8); MEDLINE (1946 to August week 4 2014); EMBASE (1980 to 2014 week 36); World Health Organization (WHO) International Clinical Trials Registry Platform (January 2015); conference proceedings and reference lists without language restrictions. SELECTION CRITERIA Randomised and quasi-randomised controlled clinical trials comparing interventions for treating fractures of the distal femur in adults. Our primary outcomes were patient-reported outcome measures (PROMs) of knee function and adverse events, including re-operations. DATA COLLECTION AND ANALYSIS Two review authors independently selected studies and performed data extraction and risk of bias assessment. We assessed treatment effects using risk ratios (RR) or mean differences (MD) and, where appropriate, we pooled data using a fixed-effect model. MAIN RESULTS We included seven studies that involved a total of 444 adults with distal femur fractures. Each of the included studies was small and assessed to be at substantial risk of bias, with four studies being quasi-randomised and none of the studies using blinding in outcome assessment. All studies provided an incomplete picture of outcome. Based on GRADE criteria, we assessed the quality of the evidence as very low for all reported outcomes, which means we are very uncertain of the reliability of these results.One study compared surgical (dynamic condylar screw (DCS) fixation) and non-surgical (skeletal traction) treatment in 42 older adults (mean age 79 years) with displaced fractures of the distal femur. This study, which did not report on PROMs, provided very low quality evidence of little between-group differences in adverse events such as death (2/20 surgical versus 1/20 non-surgical), re-operation or repeat procedures (1/20 versus 3/20) and other adverse effects including delayed union. However, while none of the findings were statistically significant, there were more complications such as pressure sores (0/20 versus 4/20) associated with prolonged immobilisation in the non-surgical group, who stayed on average one month longer in hospital.The other six studies compared different surgical interventions. Three studies, including 159 participants, compared retrograde intramedullary nail (RIMN) fixation versus DCS or blade-plate fixation (fixed-angle devices). None of these studies reported PROMS relating to function. None of the results for the reported adverse events showed a difference between the two implants. Thus, although there was very low quality evidence of a higher risk of re-operation in the RIMN group, the 95% confidence interval (CI) also included the possibility of a higher risk of re-operation for the fixed-angle device (9/83 RIMN versus 4/96 fixed-angle device; 3 studies: RR 1.85, 95% CI 0.62 to 5.57). There was no clinically important difference between the two groups found in quality of life assessed using the 36-item Short Form in one study (23 fractures). One study (18 participants) provided very low quality evidence of there being little difference in adverse events between RIMN and non-locking plate fixation. One study (53 participants) provided very low quality evidence of a higher risk of re-operation after locking plate fixation compared with a single fixed-angle device (6/28 locking plate versus 1/25 fixed-angle device; RR 5.36, 95% CI 0.69 to 41.50); however, the 95% CI also included the possibility of a higher risk of re-operation for the fixed-angle device. Neither of these trials reported on PROMs.The largest included study, which reported outcomes in 126 participants at one-year follow-up, compared RIMN versus locking plate fixation; both implants are commonly used in current practice. None of the between-group differences in the reported outcomes were statistically significant; thus the CIs crossed the line of no effect. There was very low quality evidence of better patient-reported musculoskeletal function in the RIMN group based on Short Musculoskeletal Function Assessment (0 to 100: best function) scores (e.g. dysfunction index: MD -5.90 favouring RIMN, 95% CI -15.13 to 3.33) as well as quality of life using the EuroQoL-5D Index (0 to 1: best quality of life) (MD 0.10 favouring RIMN, 95% CI -0.01 to 0.21). The CIs for both results included a clinically important effect favouring RIMN but also a clinically insignificant effect in favour of locking plate fixation. AUTHORS' CONCLUSIONS This review highlights the major limitations of the available evidence concerning current treatment interventions for fractures of the distal femur. The currently available evidence is incomplete and insufficient to inform current clinical practice. Priority should be given to a definitive, pragmatic, multicentre randomised controlled clinical trial comparing contemporary treatments such as locked plates and intramedullary nails. At minimum, these should report validated patient-reported functional and quality-of-life outcomes at one and two years. All trials should be reported in full using the CONSORT guidelines.