Kevin A. Hildebrand

Update: This article was updated on September 4, 2024 because of a previous error, which was discovered after the preliminary version of the article was posted online. In the Note listing the members of the Wrist and Elbow Research Group of Canada, the text that had read “Thomas T. Goetz, MD, FRCSC” now reads “Thomas J. Goetz, MD, FRCSC”. Background: The primary goal after open reduction and internal fixation of an established scaphoid nonunion is to achieve union. Low-intensity pulsed ultrasound (LIPUS) has been reported to increase the rate of union and to decrease the time to union for multiple fractures and nonunions in clinical and animal models. The evidence for LIPUS in the treatment of scaphoid nonunion, however, is sparse. The aim of this study was to assess whether active LIPUS (relative to sham LIPUS) accelerates the time to union following surgery for scaphoid nonunion. Methods: Adults with a scaphoid nonunion indicated for surgery were recruited for a multicenter, prospective, double-blinded randomized controlled trial. After surgery, patients self-administered activated or sham LIPUS units beginning at their first postoperative visit. The primary outcome was the time to union on serial computed tomography (CT) scans starting 6 to 8 weeks postoperatively. Secondary outcomes included patient-reported outcome measures, range of motion, and grip strength. Results: A total of 142 subjects completed the study (69 in the active LIPUS group and 73 in the sham group). The average age was 27 years, and the cohort was 88% male. There was no difference in time to union (p = 0.854; hazard ratio, 0.965; 95% confidence interval, 0.663 to 1.405). Likewise, there were no differences between the active LIPUS and sham groups with respect to any of the secondary outcomes, except for wrist flexion at baseline (p = 0.008) and at final follow-up (p = 0.043). Conclusions: Treatment with LIPUS had no effect on reducing time to union in patients who underwent surgical fixation of established scaphoid nonunions. Level of Evidence: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Background: We investigated the impact of workflow times on the outcomes of patients treated with endovascular thrombectomy (EVT) in the late time window.Methods: Individual patients’ data who underwent EVT in the late time window (onset to imaging >6 hours) were pooled from seven registries and randomized clinical trials. Multiple time intervals were analyzed. Mixed-effects logistic regression was used to estimate the likelihood of functional independence at 90 days (modified Rankin Scale 0–2). Mixed-effects negative binomial regression was used to evaluate the relationship between patient characteristics and workflow time intervals.Results: 608 patients were included. The median age was 70 years (IQR: 58–71), 307 (50.5%) were female, and 310 (53.2%) had wake-up strokes. Successful reperfusion was achieved in 493 (81.2%) patients, and 262 (44.9%) achieved 90-day mRS 0–2. The estimated odds of functional independence decreased by 13% for every 30 minute delay from emergency department (ED) arrival to imaging time and by 7% from ED arrival to the end of EVT in the entire cohort. Also, the estimated odds of functional independence decreased by 33% for every 30 minute delay in the interval from arterial puncture to end of EVT, 16% in the interval from arrival in ED to end of EVT and 6% in the interval from stroke onset to end of EVT among patients who had a wake-up stroke.Conclusion: Faster workflow from ED arrival to end of EVT is associated with improved functional independence among stroke patients treated in the late window.

Background: Improvements in surgical fixation to repair distal biceps tendon ruptures have not fully translated to earlier postoperative mobilization; it is unknown whether earlier mobilization affords earlier functional return to work. This parallel-arm randomized controlled trial compared the impact of early mobilization versus 6 weeks of postoperative immobilization following distal biceps tendon repair. Methods: One hundred and one male participants with a distal biceps tendon rupture that was amenable to a primary repair with use of a cortical button were randomized to early mobilization (self-weaning from sling and performance of active range of motion as tolerated during first 6 weeks) (n = 49) or 6 weeks of immobilization (splinting for 6 weeks with no active range of motion) (n = 52). Follow-up assessments were performed by a blinded assessor at 2 and 6 weeks and at 3, 6, and 12 months. At 12 months, distal biceps tendon integrity was verified with ultrasound. The primary outcome was return to work. Secondary outcomes were pain, range of motion, strength, shortened Disabilities of the Arm, Shoulder and Hand questionnaire (QuickDASH) score, and tendon integrity. Intention-to-treat analysis was performed. A linear mixed model for repeated measures was used to compare pain, range of motion, strength, and QuickDASH between the groups over time; return to work was assessed with use of independent t tests. Results: The groups were similar preoperatively (p ≥ 0.16). The average age (and standard deviation) was 44.7 ± 8.6 years. Eighty-three participants (82%) were followed to 12 months. There were no differences between the groups in terms of return to work (p ≥ 0.83). Participants in the early mobilization group had significantly more passive forearm supination (p = 0.04), with passive forearm pronation (p = 0.06) and active extension and supination (p = 0.09) trending toward significantly greater range of motion in the early mobilization group relative to the immobilization group. Participants in the early mobilization group had significantly better QuickDASH scores over time than those in the immobilization group (p = 0.02). There were no differences between the groups in terms of pain (p ≥ 0.45), active range of motion (p ≥ 0.09), or strength (p ≥ 0.70). Two participants (2.0%, 1 in each group) had full-thickness tears on ultrasound at 12 months (p = 0.61). Compliance was not significantly different between the groups (p = 0.16). Conclusions: Early motion after distal biceps tendon repair with cortical button fixation is well tolerated and does not appear to be associated with adverse outcomes. No clinically important group differences were seen. Level of Evidence: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Background: Posttraumatic joint contracture is a debilitating complication following an acute fracture or intra-articular injury that can lead to loss of motion and an inability to complete activities of daily living. In prior studies using an established in vivo model, we found that ketotifen fumarate (KF), a mast cell stabilizer, was associated with a significant reduction in the severity of posttraumatic joint contracture. Our primary research question in the current study was to determine whether a dose-response relationship exists between KF and posttraumatic joint contracture reduction. Methods: A standardized operative method to create posttraumatic joint contracture in a knee was performed on skeletally mature New Zealand White rabbits. The animals were randomly assigned to 1 of 5 groups (n = 10 per group): a nonoperative control group, an operative control group, or 1 of 3 experimental KF groups (0.01 mg/kg [the KF 0.01 group], 0.1 mg/kg [KF 0.1], or 5.0 mg/kg [KF 5.0]). Flexion contractures were measured following 8 weeks of knee immobilization using a hydraulic material-testing machine. The posterior knee joint capsules were then harvested for quantification of myofibroblast and mast cell numbers with immunohistochemistry analysis. Results: Forty-five rabbits were used in the final analysis. Contracture severity was significantly reduced in the KF 0.1 group (p = 0.016) and the KF 5.0 group (p = 0.001) compared with the operative control group. When converted to a percent response, posttraumatic joint contracture reduction was 13%, 45%, and 63% for the KF 0.01, KF 0.1, and KF 5.0 groups, respectively. A half-maximal effective concentration (EC₅₀) for KF of 0.22 mg/kg was established. There was also a decrease in myofibroblasts, mast cells, and substance P-containing nerve fiber counts with increasing doses of KF. Conclusions: Using a preclinical, rabbit in vivo model of posttraumatic joint contracture, increasing doses of KF were associated with decreasing biomechanical estimates of knee posttraumatic joint contracture as well as decreasing numbers of myofibroblasts, mast cells, and substance P-containing nerve fibers. Clinical Relevance: KF has been used safely in humans for more than 40 years and, to our knowledge, is the first and only agent ready to be potentially translated into an effective treatment for posttraumatic joint contracture.

Post-traumatic contractures are a frequent complication of elbow fractures or dislocations. Periarticular structures such as ligaments, muscle-tendon units, and the joint capsule undergo a fibrotic reaction in response to the injury. While operative approaches are commonly used to address post-traumatic contractures, the results of these procedures infrequently provide restoration of full range of motion (ROM). Nonsurgical methods offer the potential to prevent the development of post-traumatic contractures following injury, or to be an adjunct to an operation to restore full motion following operative release of established post-traumatic contractures. Using animal models of post-traumatic contractures, several authors have reported on nonsurgical methods to alter collagen, inhibit proliferation of (myo)fibroblasts, or modify hyaluronic acid, inflammation or growth factors. Three small, nonrandomized clinical trials have examined nonsurgical adjunct approaches to prevent contractures after fracture-dislocations or recurrence of contractures after operative releases of established contractures. A review of these articles is followed by a discussion of approaches and platforms to advance the understanding of the pathological processes, identify candidate agents, proof of principle in animal models, clinical trials for efficacy and safety, and adoption into clinical practice.