Risk Factors of Failure in 228 Periprosthetic Distal Femur Fractures: A Multicenter Study.

OBJECTIVES: To identify risk factors of reoperation to promote union or to address deep surgical-site infection (DSSI) in periprosthetic distal femur fractures treated with lateral distal femoral locking plates (LDFLPs). DESIGN: Multicenter retrospective cohort study. SETTING: Ten level-I trauma centers. PATIENT SELECTION CRITERIA: Patients with Orthopaedic Trauma Association/Association of Osteosynthesis (OTA/AO) 33A or 33C periprosthetic distal femur fractures who underwent surgical fixation between January 2012 and December 2019 exclusively using LDFLPs were eligible for inclusion. Patients with pathologic fractures or with follow-up less than 3 months without an outcome event (unplanned reoperation to promote union or for deep surgical infection) before this time point were excluded. Fracture fixation constructs used medial plates, intramedullary nails, or hybrid fixation constructs were excluded from analysis. OUTCOME MEASURES AND COMPARISONS: To examine the influence of patient demographics, injury characteristics, and features of the fracture fixation construct on the occurrence of unplanned reoperation to promote union or to address a DSSI. RESULTS: There was an 8.3% rate (19/228) of unplanned reoperation to promote union. Predictive factors for the need for reoperation to promote union included increasing body mass index (odds ratio [OR] = 1.09; 95% confidence interval [CI]: 1.02-1.16; P = 0.01), increasing number of screws in the distal fracture segment (OR = 1.73; 95% CI: 1.06-2.95; P = 0.03), and decreasing proportion of proximal segment screws that are locking (OR = 0.17; 95% CI: 0.03-0.70; P = 0.02) There was a 4.8% rate (11/228) of reoperation to address DSSI. There were no statistically significant predictive factors identified as risk factors of the need for reoperation to address DSSI ( P > 0.05). CONCLUSIONS: 8.3% of periprosthetic distal femur fractures treated at 10 centers with LDFLPs underwent unplanned reoperation to promote union. Increasing patient body mass index and increasing number of screws in the distal fracture segment were found to be predictive factors, whereas increased locking screws in the proximal segment were found to be protective. 4.8% of patients in this cohort underwent reoperation to address DSSI. LEVEL OF EVIDENCE: Level III. See Instructions for Authors for a complete description of levels of evidence.

Worse Quality of Life Associated With Hyperextension Varus Tibial Plateau Fracture Pattern.

OBJECTIVES: Compare patient-reported outcome measures between hyperextension varus tibial plateau (HEVTP) fracture patterns to non-HEVTP fracture patterns. DESIGN: Retrospective study. SETTING: Single academic Level 1 Trauma Center. PATIENT SELECTION CRITERIA: All patients who underwent fixation of a tibial plateau fracture from 2016 to 2021 were collected. Exclusion criteria included inaccurate Current Procedural Terminology code, ipsilateral compartment syndrome, bilateral fractures, incomplete medical records, or follow-up <10 months. OUTCOME MEASURES AND COMPARISONS: In patients who underwent fixation of a tibial plateau fracture, compare Patient-Reported Outcomes Measurement Information System-Physical Function, PROMIS Preference, and Knee Injury and Osteoarthritis Outcome Score (KOOS) between patients with a HEVTP pattern with those without. RESULTS: Two-hundred and seven patients were included, of which 17 (8%) had HEVTP fractures. Compared with non-HEVTP fracture patterns, patients with HEVTP injuries were younger (42.6 vs. 51.0, P = 0.025), more commonly male (71% vs. 44%, P = 0.033), and had higher body mass index (32.8 vs. 28.0, P = 0.05). HEVTP fractures had significantly more ligamentous knee (29% vs. 6%, P = 0.007) and vascular (12% vs. 1%, P = 0.035) injuries. Patient-Reported Outcomes Measurement Information System-Physical Function scores were similar between groups; however, PROMIS-Preference (0.37 vs. 0.51, P = 0.017) was significantly lower in HEVTP fractures. KOOS pain, activities of daily living, and quality-of-life scores were statistically lower in HEVTP fractures, but only KOOS quality-of-life was clinically relevant (41.7 vs. 59.3, P = 0.004). CONCLUSIONS: The HEVTP fracture pattern, whether unicondylar or bicondylar, was associated with a higher rate of ligamentous and vascular injuries compared with non-HEVTP fracture patterns. They were also associated with worse health-related quality of life at midterm follow-up. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Technical Factors Contributing to Nonunion in Supracondylar Distal Femur Fractures Treated With Lateral Locked Plating: A Risk-Stratified Analysis.

OBJECTIVE: To identify technical factors associated with nonunion after operative treatment with lateral locked plating. DESIGN: Retrospective cohort study. SETTING: Ten Level I trauma centers. PATIENT SELECTION CRITERIA: Adult patients with supracondylar distal femur fractures (OTA/AO type 33A or C) treated with lateral locked plating from 2010 through 2019. OUTCOME MEASURES AND COMPARISONS: Surgery for nonunion stratified by risk for nonunion. RESULTS: The cohort included 615 patients with supracondylar distal femur fractures. The median patient age was 61 years old (interquartile range: 46 -72years) and 375 (61%) were female. Observed were nonunion rates of 2% in a low risk of nonunion group (n = 129), 4% in a medium-risk group (n = 333), and 14% in a high-risk group (n = 153). Varus malreduction with an anatomic lateral distal femoral angle greater than 84 degrees, was associated with double the odds of nonunion compared to those without such varus [odds ratio, 2.1; 95% confidence interval (CI), 1.1-4.2; P = 0.03]. Malreduction by medial translation of the articular block increased the odds of nonunion, with 30% increased odds per 4 mm of medial translation (95% CI, 1.0-1.6; P = 0.03). Working length increased the odds of nonunion in the medium risk group, with an 18% increase in nonunion per 10-mm increase in working length (95% CI, 1.0-1.4; P = 0.01). Increased proximal screw density was protective against nonunion (odds ratio, 0.71; 95% CI, 0.53-0.92; P = 0.02) but yielded lower mRUST scores with each 0.1 increase in screw density associated with a 0.4-point lower mRUST (95% CI, -0.55 to -0.15; P < 0.001). Lateral plate length and type of plate material were not associated with nonunion. ( P > 0.05). CONCLUSIONS: Malreduction is a surgeon-controlled variable associated with nonunion after lateral locked plating of supracondylar distal femur fractures. Longer working lengths were associated with nonunion, suggesting that bridge plating may be less likely to succeed for longer fractures. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.