Comparison of Risk Factors and Postoperative Outcomes in Syndesmosis Injuries with Various Ankle Fracture Types.

There is a lack of understanding of risk factors and postoperative outcomes of syndesmotic injuries with singular versus multipart fractures. A retrospective analysis was done between 2008 and 2016, utilizing the American College of Surgeons National Surgical Improvement Program database. Patients with open reduction and internal fixation of isolated lateral malleolus fractures, bimalleolar fractures, or trimalleolar fractures were identified. A total of 2045 patients underwent syndesmotic fixation. Subjects with bimalleolar or trimalleolar fractures were more likely than those with unimalleolar fractures to be Caucasian (odds ratio [OR] = 1.5 and 1.9), female (OR = 1.8 and 2.9), aged > 65 years (OR = 1.6 and 1.9), or have American Society of Anesthesiologists (ASA) classification III (OR =1.5 and 1.4) (all, P ≤ 0.028). Patients with a unimalleolar fracture were more likely than those with a bimalleolar or trimalleolar fracture to be male (OR = 1.8 and 2.9), African American (OR = 1.5 and 1.8), aged < 30 years (OR = 1.4 and 1.8), or present with an ASA I classification (OR = 1.6 and 2.0) (all, P ≤ 0.004). Subjects with bimalleolar or trimalleolar fractures were more likely than those with unimalleolar fractures to have lengthier hospital stays (OR = 1.8 and 2.1), while patients with trimalleolar fractures were more likely than those with unimalleolar fractures to have hypoalbuminemia (OR = 2.3), develop a complication (OR = 2.2) or an open wound (OR = 1.9), or to be readmitted (OR = 2.2) (all, P ≤ 0.036). In this study, comorbidity rates and adverse postoperative outcomes significantly increased as the number-part fractures increased in syndesmotic fixation patients. Risk factors also varied across fracture severity.

Ankle Fracture Epidemiology in the United States: Patient-Related Trends and Mechanisms of Injury.

Current nationwide epidemiological data regarding ankle fractures are scarce. Such information is important towards better quantifying the mortality associated with such injuries, financial impact, as well as the implementation of preventative measures. This study evaluated the epidemiology of ankle fractures that occurred during a 5-year period. Specifically, we evaluated demographics, mechanism of injury, and disposition. The National Electronic Injury Surveillance System was queried to identify all patients with ankle fractures that presented to US hospital emergency departments between 2012 and 2016. Census data were used to determine the incidence rates of ankle fractures in terms of age, sex, and race. There was an estimated total of 673,214 ankle fractures that occurred during this period, with an incidence rate of 4.22/10,000 person-years. The mean age of patients with an ankle fracture was 37 ± 22.86 (SD) years; 23.5% of ankle fractures occurred in patients aged 10 to 19 years (7.56/10,000 person-years). In addition, 44% of ankle fractures occurred in men (3.81/10,000 person-years), whereas 56% occurred in women (4.63/10,000 person-years). Data on race/ethnicity were available for 71% of the subjects, with incidence rates of 2.85/10,000 person-years for whites, 3.01/10,000 person-years for blacks, and 4.08/10,000 person-years for others. The most common mechanism of injury was falls (54.83%), followed by sports (20.76%), exercise (16.84%), jumping (4.42%), trauma (2.84%), and other (0.30%). For disposition, 81.84% of patients were treated and released, 1.43% were transferred, 16.01% were admitted, 0.59% were held for observation, and 0.13% left against medical advice. The highest incidence of ankle fractures in men occurred in the 10-to-19-years age group, but women were more commonly affected in all other age groups.

Evaluating success rate and comparing complications of operative techniques used to treat chronic syndesmosis injuries.

PURPOSE: To assess the success rate and complications of the surgical interventions used to manage chronic syndesmosis injuries. METHODS: Multiple online databases were queried to identify studies reporting operative intervention for chronic syndesmosis injuries. RESULTS: Modalities of operative fixation include suture-button fixation, arthroscopy and debridement, as well as arthrodesis. The use of operative treatment is effective; however, more direct comparison studies are necessary to evaluate the efficacy of each treatment. CONCLUSION: Various operative procedures have been used for the management of chronic syndesmotic injuries but further prospective studies are necessary to determine the type of treatment that should be indicated.

Rotational Deformity of the First Ray Precludes Accurate Distal Metatarsal Articular Angle Measurement in Hallux Valgus.

The routine workup of hallux valgus includes measurements of the distal metatarsal articular angle (DMAA). However, this angle may not be a reliable measurement when rotational deformities occur. Eight matched cadaveric feet were evaluated radiographically using fluoroscopy. The intermetatarsal angle (IMA), hallux valgus angle, and DMAA were evaluated as a baseline. Then, we assessed whether axial rotation of 15°, 30°, 45°, and 60° affected the accuracy of the IMA and the DMAA significantly. Statistical evaluation was performed using Student's t tests and analysis of variance. The IMA remained stable for each anterior-posterior image despite rotation of the distal segment, with a mean difference of less than 2.5°. However, the DMAA was not constant, having different angles of rotation through the osteotomy site. We were able to demonstrate that measurement of the DMAA varies significantly with rotation of the distal first metatarsal. Using the DMAA to assess first metatarsophalangeal joint congruency should be done cautiously because it may estimate unreliably and inaccurately the 3D deformity often encountered in pathologic hallux valgus.

Strength of Syndesmosis Fixation: Two TightRope versus One TightRope with Plate-and-Screw Construct.

Injuries involving the distal tibiofibular syndesmosis can lead to critical destabilization of the ankle mortise. Although specific indications for operative fixation remain unclear, accurate reduction of the syndesmosis has been correlated with the best functional outcomes. The purpose of this study was to evaluate the maximum torque and rotation to failure after fixation with a novel construct. Seven pairs (14 ankles) of embalmed cadaveric lower legs, disarticulated at the knee, were obtained. Each pair was randomly assigned to receive either two TightRopes (Arthrex) or a plate-and-screw construct with one TightRope. All samples were mechanically tested in torsion to determine peak torque, torsional stiffness, and the maximum rotation angle at which failure occurred. Differences between the groups were compared using paired Student's t test. The maximum torque to failure after fixation was not significantly different between the two TightRopes (28.8 N*m; range, 7.3-49.7 N*m) and the one TightRope group (29.5 N*m; range, 9.2-44.9 N*m; p = 0.92). The maximum rotation to fracture after fixation was not significantly different between the two TightRopes (33.3 degrees; range, 21.6-57.0 degrees) and one TightRope group (38.6 degrees; range, 23.0-73.9 degrees). All specimens failed with the fracture of the fibula at the level of the inferior syndesmotic screw. The similar load to failure of the two TightRope and the one TightRope and plate-and-screw plate suggested similar stiffness between the two constructs. The addition of the plate may improve distribution of forces at the level of syndesmosis, reducing stress risers and decreasing the risk of failure, as demonstrated by a lower rotation to failure of the one TightRope with plate-and-screw construct. In addition, this construct is not likely to not be associated with any substantial cost increase. Further clinical studies may further elucidate the role of plate and/or TightRope augmentation to syndesmosis fixation.

A Biomechanical Comparison of Different Tendon Repair Techniques.

Previous studies have examined multiple suture techniques for the repair of ruptured tendons. In this study, we investigated how the two- and four-stranded Krackow suture weave techniques compared with a novel Krackow/Bunnell suture technique. Our hypothesis was that the Krackow/Bunnell suture would have greater strength compared with the two- and four-stranded Krackow suture in terms of resistance to pullout from the muscle tendon. Thirty fresh bovine Achilles tendons were assigned randomly to three groups: (1) two-stranded Krackow, (2) fourstranded Krackow, and (3) the Krackow/Bunnell combination. After suture placement, all specimens were subjected to initial cyclic loading (0-200 N for 200 cycles) and then the tension to failure force defined as the pullout through the muscle tendon was evaluated. Significantly greater deformation before suture failure was seen in the Krackow/Bunnell group compared with the four-stranded Krackow construct (36.2 vs. 28.7 mm, p = 0.009), as well as greater energy required to rupture the suture (4635 vs. 3346 N/mm; p = 0.016). There was no significant difference with regard to the force to failure between the two groups (four-stranded Krackow vs. Krackow/Bunnell). The two-stranded Krackow was found to be inferior to both the four-stranded Krakow and the Krakow/Bunnell techniques with regard to load to failure. We have found that the Krackow/Bunnell suture technique is at least comparable to, if not superior to, the four-stranded Krackow technique with regard to deformation before suture failure and energy required to rupture the tendon. Therefore, the Krackow/Bunnell technique may be an optimal construct if the surgeon is concerned about suture pullout through the tendon; however, future studies evaluating this technique in the clinical setting are required before making any final conclusions for patient use.

Biomechanical evaluation of varying the number of loops in a repair of a physiological model of Achilles tendon rupture.

BACKGROUND: Numerous suturing techniques have been described to treat Achilles tendon ruptures. No prior studies have evaluated frayed tendon ends on construct strength and whether this allows for less extensile exposure. METHODS: Forty bovine Achilles tendons were divided into groups: 1 control and 4 experimental. Experimental groups were sectioned with ends frayed longitudinally in 2 mm intervals for 2 cm with no fraying for the control group. Four-stand Krackow sutures were used for repairs with 3 loops in the control group, 2 loops in frayed section for experimental groups, and varying numbers of loops (1-4) in healthy tendon. Samples were tested in loading cells at 100 N and 190 N for 1000 cycles. Gap width and maximum load failure were measured. RESULTS: Gapping was <5 mm in controls at 100 N-190 N, significantly lower than experimentals. Greatest gapping occurred in groups with 1-2 loops in healthy tendon (10.9-13.9 mm). Most early catastrophic failures (5/8) occurred in groups with 1-2 loops in healthy tendon. Two failures at 100 N occurred in 1-loop healthy tendons. The least failures occurred in controls (2/8), at 190 N. CONCLUSION: Suture loops incorporated into frayed tendon portions predisposed repairs to significantly greater gapping and lower maximal failure forces than 4-strand Krackow repairs in unfrayed tendons. CLINICAL RELEVANCE: We cannot recommend attempting more limited exposures with sutures in frayed tendon as this may lead to early repair failure. We provided a physiologic model utilizing frayed tendon ends that resembles in vivo Achilles tendon rupture.