Intramedullary Screw Fixation of Metacarpal and Phalangeal Fractures.

Metacarpal and phalangeal fractures are the second and third most common hand and wrist fractures seen in the emergency department. There are a multitude of operative fixation methods for metacarpal and phalangeal fractures, including closed reduction percutaneous pinning, open reduction internal fixation, external fixation, and intramedullary screw fixation. Although intramedullary fixation is a relatively new surgical technique, it is gaining in popularity as it allows patients to resume range of motion early in the postoperative period with excellent clinical outcomes.

Staple Fixation in Ulnar-Shortening Osteotomies.

Ulnar-sided wrist pain is commonly caused by the ulnar impaction syndrome. Ulnar-shortening osteotomy is a surgical treatment that is used to address ulnar impaction syndrome that fails conservative management. Unfortunately, hardware irritation and nonunion are well-known complications of this procedure. This case report details the course of two patients with nonunion after ulnar-shortening osteotomy who were treated with a combination of a nitinol compression staple and neutralization plate. Further investigation is required to determine the long-term outcomes and indications for nitinol-staple fixation for nonunion after ulnar-shortening osteotomy.

Comparison of Early versus Late Below Knee Amputation After Trauma With Standardized Prosthetic Care.

Background: High energy, lower extremity trauma is associated with longstanding pain and functional limitations. The clinical decision to proceed with early amputation or limb salvage is often controversial. This study was designed to compare differences in complications, costs, and clinical outcomes of below knee amputation (BKA) performed early after injury or after attempted limb salvage in a hospital with standardized prosthetic care following amputation. Methods: This is a retrospective comparative study of subjects who underwent BKA for a traumatic injury at a single level 1 trauma center and received standardized prosthetic care from a single manufacturer from 1999-2016 with minimum 2-year post-amputation follow up. Outcomes collected included demographics, surgical management, unplanned re-operations, and hospital and prosthetic cost data 2 years from time of injury. Results: Overall, 79 subjects met criteria. Early amputation (EA) was defined by median duration between injury and amputation (6 weeks) with 41 subjects in the EA group and 38 subjects in the late amputation (LA) group. Subjects in the EA group were more likely to have open fractures, high energy mechanism, and less likely to have medical comorbidities. Post-amputation infection was common in both groups (17/41 (42%) vs 17/38 (45%), p=0.77). Subjects undergoing EA were more likely to require unplanned post-amputation revision, 22/41 (54%) versus 10/38 (27%), p=0.017. Hospital costs and prosthetics/orthotics costs from the time of injury to two years following amputation were comparable, with mean hospital EA costs $136,044 versus LA costs $125,065, p=0.38. Mean prosthetics/orthotics costs of EA subjects were $33,252 versus LA costs $37,684, p=0.59. Conclusion: Unplanned post-amputation revision surgeries were more common when BKA was performed early after trauma. Otherwise, outcomes and cost were comparable when amputation was performed early versus late. Level of Evidence: IV.

Novel patient-derived models of desmoplastic small round cell tumor confirm a targetable dependency on ERBB signaling.

Desmoplastic small round cell tumor (DSRCT) is characterized by the t(11;22)(p13;q12) translocation, which fuses the transcriptional regulatory domain of EWSR1 with the DNA-binding domain of WT1, resulting in the oncogenic EWSR1-WT1 fusion protein. The paucity of DSRCT disease models has hampered preclinical therapeutic studies on this aggressive cancer. Here, we developed preclinical disease models and mined DSRCT expression profiles to identify genetic vulnerabilities that could be leveraged for new therapies. We describe four DSRCT cell lines and one patient-derived xenograft model. Transcriptomic, proteomic and biochemical profiling showed evidence of activation of the ERBB pathway. Ectopic expression of EWSR1-WT1 resulted in upregulation of ERRB family ligands. Treatment of DSRCT cell lines with ERBB ligands resulted in activation of EGFR, ERBB2, ERK1/2 and AKT, and stimulation of cell growth. Antagonizing EGFR function with shRNAs, small-molecule inhibitors (afatinib, neratinib) or an anti-EGFR antibody (cetuximab) inhibited proliferation of DSRCT cells. Finally, treatment of mice bearing DSRCT xenografts with a combination of cetuximab and afatinib significantly reduced tumor growth. These data provide a rationale for evaluating EGFR antagonists in patients with DSRCT. This article has an associated First Person interview with the joint first authors of the paper.

Weight-Bearing CT Scan After Tibial Pilon Fracture Demonstrates Significant Early Joint-Space Narrowing.

BACKGROUND: Posttraumatic osteoarthritis (PTOA) is a common and early sequela of tibial pilon fractures resulting in substantial long-term disability. New approaches are needed to objectively and reliably quantify early disease progression in order to critically assess the impact of interventions aimed at preventing or mitigating PTOA. Weight-bearing computed tomography (WBCT) scans provide a means for measuring joint space while the ankle is in a loaded, functional position. We assessed the interrater and intrarater reliability of a standardized, regional method to quantify joint-space loss following tibial pilon fracture compared with the uninjured contralateral ankle. METHODS: We prospectively enrolled 20 patients with intra-articular tibial pilon fractures that were surgically treated at 1 of 2 level-I trauma centers. Six months after injury, bilateral ankle WBCT scans were obtained. Joint space was measured by 4 reviewers at 9 discrete regions of the tibiotalar articulation on sagittal images. Measurements were repeated by reviewers 2 weeks later. To characterize the measurement method, interrater correlation coefficient estimates and test-retest reproducibility were calculated. RESULTS: The mean tibiotalar joint space was 21% less in the injured ankles compared with the contralateral uninjured ankles (p < 0.0001). The middle-lateral and middle-central regions of the joint demonstrated the greatest decrease in joint space between injured and uninured ankles. The interrater correlation coefficient of the measurement technique was 0.88, and the test-retest reproducibility was 0.80, indicating good reliability and reproducibility of the method. CONCLUSIONS: We developed a simple, standardized, and reliable technique to quantify tibiotalar joint space following tibial pilon fracture on WBCT. Significant loss of joint space is seen 6 months after the injury. This tool can be used to longitudinally quantify loss of joint space following pilon fracture and assess the impact of interventions to reduce PTOA.

Subsequent Pain or Injury After Foot and Ankle Surgery in Patients Receiving Workers' Compensation.

BACKGROUND: Workers' compensation (WC) has been associated with poor outcomes following a variety of injuries and surgeries, but rates of subsequent pain or injury (SPI) following surgery have not been studied. The purpose of this study was to investigate the rates, locations, and risk factors of SPI in WC patients and non-WC patients who underwent the same surgeries. METHODS: With institutional review board approval, records from foot or ankle surgery performed by author P.P. from 2009 to 2015 were obtained. A retrospective chart review was performed on all WC and non-WC patients with at least 1 Current Procedural Terminology code of interest. SPI was defined as a new injury at a different anatomical location occurring 2 months to 2 years after the index surgery. Chi-square and 2-tailed t tests were used to compare risk factors and rates of SPI in both groups. RESULTS: The WC population had higher rates of SPI than the non-WC population. Specifically, 13 of 56 WC patients (23.2%) vs 12 of 165 non-WC patients (7.3%) reported SPI (P = .001). The hip, knee, and contralateral foot and ankle were common areas of SPI in both groups. Legal representation and increased age were risk factors for SPI in the WC population. Specifically, 10 of 13 WC patients with SPI had legal representation vs 16 of 43 WC patients without SPI (P = .02). Female sex was a risk factor for SPI in the non-WC population. CONCLUSIONS: WC patients had higher rates of subsequent pain or injury than non-WC patients. Legal representation was a risk factor for SPI in the WC population. LEVEL OF EVIDENCE: Level III, comparative series.

Force transmission at cell-cell and cell-matrix adhesions.

All cells are subjected to mechanical forces throughout their lifetimes. These forces are sensed by cell surface adhesion receptors and trigger robust actin cytoskeletal rearrangements and growth of the associated adhesion complex to counter the applied force. In this review, we discuss how integrins and cadherins sense force and transmit these forces into the cell interior. We focus on the complement of proteins each adhesion complex recruits to bear the force and the signal transduction pathways activated to allow the cell to tune its contractility. A discussion of the similarities, differences, and crosstalk between cadherin- and integrin-mediated force transmission is also presented.