Postless Hip Distraction Systems Decrease the Amount of Traction Force Needed to Obtain Adequate Hip Distraction Versus a Conventional Post Hip Distractor.

PURPOSE: To directly compare hip distraction distance and traction force data for hip arthroscopy performed using a post-basedsystem versus a postless system. METHODS: Adult patients undergoing primary hip arthroscopy for femoroacetabular impingement were prospectively enrolled. Before March 26, 2019, arthroscopy was performed using a post-based system. After this date, the senior author converted to using a postless system. Intraoperative traction force and fluoroscopic distraction distance were measured to calculate hip stiffness coefficients at holding traction (k-hold) and maximal traction (k-max). We used multivariable regression analysis to determine whether postless arthroscopy was predictive of lower stiffness coefficients when controlling for other relevant patient-specific factors. RESULTS: Hip arthroscopy was performed with a post-based system in 105 patients and with a postless system in 51. Mean holding traction force (67.5 ± 14.0 kilograms-force [kgf] vs 55.8 ± 15.3 kgf) and mean maximum traction force (96.0 ± 16.6 kgf vs 69.9 ± 14.1 kgf) were significantly lower in the postless group. On multivariable analysis, postless traction was an independent predictor of decreased k-hold (ß = -31.4; 95% confidence interval, -61.2 to -1.6) and decreased k-max (ß = -90.4; 95% confidence interval, -127.8 to -53.1). Male sex, Beighton score of 0, and poor hamstring flexibility were also predictors of increased k-hold and k-max in the multivariable model. CONCLUSIONS: Postless traction systems decrease the amount of traction force required for adequate hip distraction for both maximal and holding traction forces when compared with post-based systems. Postless traction systems may help further reduce distraction-type neurologic injuries and pain after hip arthroscopy by lowering the traction force required to safely distract the hip. LEVEL OF EVIDENCE: Level III, prospective cohort-historical control comparative study.

The Prevalence of Metabolic and Endocrine Disturbances on Fracture Nonunion.

OBJECTIVE: This study aims to determine the prevalence of metabolic disturbance in all fracture nonunion cases and identify the most common endocrine abnormalities seen using a simple screening algorithm. METHODS: A retrospective review study was performed evaluating patients who underwent operative intervention for nonunion from January 2010 to December 2018 at 2 level-1 trauma centers. Preoperative laboratory values were recorded for a 9-test "nonunion panel." A metabolic or endocrine abnormality, specifically an abnormality in the thyroid or parathyroid axis, was evaluated. RESULTS: 42% of patients had an undiagnosed metabolic laboratory abnormality. When multiple tests were used, the rate of metabolic dysfunction was between 60% and 75%, depending on the definition of vitamin D insufficiency vs deficiency used. CONCLUSION: Results indicate a relatively high prevalence of metabolic disturbance in patients with nonunion and suggest metabolic screening for all nonunion patients not only those without a mechanical or infectious cause. LEVEL OF EVIDENCE: IV, retrospective case series.