Medial and lateral dual plating of native distal femur fractures: a systematic literature review.

Introduction: Lateral locked plating (LLP) development has improved outcomes for distal femur fractures. However, there is still a modest rate of nonunion in fractures treated with LLP alone, with higher nonunion risk in high-energy fractures, intra-articular involvement, poor bone quality, severe comminution, or bone loss. Several recent studies have demonstrated both the safety and the biomechanical advantage of dual medial and lateral plating (DP). The purpose of this study was to evaluate the clinical outcomes of DP for native distal femoral fractures by performing a systematic review of the literature. Methods: Studies reporting clinical outcomes for DP of native distal femur fractures were identified and systematically reviewed. Publications without full-text manuscripts, those solely involving periprosthetic fractures, or fractures other than distal femur fractures were excluded. Fracture type, mean follow-up, open versus closed fracture, number of bone grafting procedures, nonunion, reoperation rates, and complication data were collected. Methodologic study quality was assessed using the Coleman methodology score. Results: The initial electronic review and reverse inclusion protocol identified 1484 publications. After removal of duplicates and abstract review to exclude studies that did not discuss clinical treatment of femur fractures with dual plating, 101 potential manuscripts were identified and manually reviewed. After final review, 12 studies were included in this study. There were 199 fractures with average follow-up time of 13.72 months. Unplanned reoperations and nonunion occurred in 19 (8.5%) and 9 (4.5%) cases, respectively. The most frequently reported complications were superficial infection (n = 6, 3%) and deep infection (n = 5, 2.5%) postoperatively. Other complications included delayed union (n = 6, 3%) not requiring additional surgical treatment and knee stiffness in four patients (2%) necessitating manipulation under anesthesia or lysis of adhesions. The average Coleman score was 50.5 (range 13.5-72), suggesting that included studies were of moderate-to-poor quality. Conclusions: Clinical research interest in DP of distal femoral fractures has markedly increased in the past few decades. The current data suggest that DP of native distal femoral fractures is associated with favorable nonunion and reoperation rates compared with previously published rates associated with LLP alone. In the current review, DP of distal femoral fractures was associated with acceptable rates of complications and generally good functional outcomes. More high-quality, directly comparable research is necessary to validate the conclusions of this review.

Rules of 6 criteria predict dialysis fistula maturation but not all rules are equal.

OBJECTIVE: The Rules of 6 (flow volume >600 mL/min, vein diameter >6 mm, vein depth <6 mm) are widely used to determine when an arteriovenous fistula (AVF) will support dialysis. Thus, we tested the utility of the Rules of 6 in clinical practice. METHODS: We retrospectively reviewed AVFs created at a single center from 2016 to 2019 for patients who had undergone dialysis within the same healthcare system. Clinical records and postoperative ultrasound studies were reviewed for the Rules of 6 criteria. Maturation was defined as use of the AVF with two needles for 75% of the dialysis sessions for a continuous 4-week period, with a mean flow of 300 mL/min or urea clearance (Kt/V) of 1.2. Predictors of maturation were assessed using logistic regression and receiver operating characteristic (ROC) curves. RESULTS: Five surgeons performed 202 AVFs of three types during 2016 to 2019 (radial-cephalic, n = 49; brachial-cephalic, n = 87; brachial-basilic, n = 66). Maturation occurred in 150 AVFs (74%; primary, n = 101 [50%]; assisted, n = 49 [24%]), while 52 (26%) failed to mature. Maturation did not vary by AVF type or patient sex or diabetes status. A higher body mass index was associated with failure to mature (P = .004). Only 16 mature AVFs (11%) met all three Rules of 6 using mean values for flow, diameter, and depth. However, 101 (67%) met all three Rules using the extreme, maximum or minimum, values. On multivariate analysis, each Rule of 6 was independently associated with maturation. If all three Rules were met, the AVF was nearly 10-fold more likely to have matured compared with an AVF satisfying no Rule. The body mass index correlated strongly with the vein depth (P < .001); however, both characteristics independently predicted maturation. The chance of maturation was highest if flow and depth Rules were met (positive predictive value [PPV], 93%); if all three rules were met, the PPV was 92%. The ROC area under curve (AUC) values for meeting flow volume and vein depth Rules together were higher than if all three Rules had been satisfied (0.784 vs 0.754). The PPV for diameter alone (78%) was the lowest of all PPVs for the three Rules and the ROC-AUC was only 0.588. If all three Rules together were not satisfied using extreme values, the negative predictive value was only 47%. CONCLUSIONS: The Rules of 6 predict AVF maturation, especially when using extreme, maximum or minimum, values to satisfy each Rule. Flow volume and vein depth together predict maturation equally as well as meeting all three Rules. Vein diameter seems less important. The Rules of 6 might be too stringent if used exclusively to predict for functional AVF maturation.

Biomechanical and anatomical considerations for dual plating of distal femur fractures: a systematic literature review.

INTRODUCTION: Distal femur fractures are challenging injuries historically associated with high rates of nonunion and varus collapse with operative management. As a result, clinical and research interest in dual plating (DP) of distal femur fractures has seen a dramatic increase in recent years. The purpose of this study was to systematically review the literature regarding vascular anatomy and biomechanics of distal femur fractures treated with DP constructs. MATERIALS AND METHODS: A systematic literature review of two medical databases (PubMed & Scopus) was performed to identify peer-reviewed studies on the anatomy and biomechanics regarding DP of distal femur fractures. A total of 1,001 papers were evaluated and 14 papers met inclusion criteria (6 anatomy and 8 biomechanics). Methodological quality scores were used to assess quality and potential bias in the included studies. RESULTS: In the biomechanical studies, DP constructs demonstrated greater axial and rotational stiffness, as well as less displacement and fewer incidences of failure compared to all other constructs. Vascular studies showed that the femoral artery crosses the mid-shaft femur approximately 16.0-18.8 cm proximal to the adductor tubercle and it is located on average 16.6-31.1 mm from the femoral shaft at this location, suggesting that medial plate application can be achieved safely in the distal femur. The methodological quality of the included studies was good for biomechanical studies (Traa score 79.1; range 53-92.5) and excellent for anatomical studies (QUACs score 81.9; range 69.0-88.5). CONCLUSIONS: Existing biomechanics literature suggests that DP constructs are mechanically stronger than other constructs commonly used in the treatment of distal femur fractures. Furthermore, medial distal femoral anatomy allows for safe application of DP constructs, even in a minimally invasive fashion. Dual plating should be considered for patients with distal femur fractures that have risk factors for instability, varus collapse, or nonunion.