Angiogenesis is a key component of bone repair. New blood vessels bring oxygen and nutrients to the highly metabolically active regenerating callus and serve as a route for inflammatory cells and cartilage and bone precursor cells to reach the injury site. Angiogenesis is regulated by a variety of growth factors, notably vascular endothelial growth factor (VEGF), which are produced by inflammatory cells and stromal cells to induce blood vessel in-growth. A variety of studies with transgenic and gene-targeted mice have demonstrated the importance of angiogenesis in fracture healing, and have provided insights into regulatory processes governing fracture angiogenesis. Indeed, in animal models enhancing angiogenesis promotes bone regeneration, suggesting that modifying fracture vascularization could be a viable therapeutic approach for accelerated/improved bone regeneration clinically.

Our study showed altered healing capacity in a relevant animal model of geriatric fracture healing. The understanding that callus expansion and bone volume are decreased with aging can help guide the development of targeted therapeutics for these difficult to heal fractures.

Based on best available evidence, knee arthrodesis should be strongly considered as the treatment of choice for patients who have persistent infected TKA after a failed two-stage reimplantation procedure. We recognize that particular circumstances such as severe bone loss can preclude or limit the applicability of fusion as an option and that individual clinical circumstances must always dictate the best treatment, but where arthrodesis is practical, our model supports it as the best approach.

The rotator cuff assists in shoulder movement and provides dynamic stability to the glenohumeral joint. Specifically, the anterior–posterior (AP) force balance, provided by the subscapularis anteriorly and the infraspinatus and teres minor posteriorly, is critical for joint stability and concentric rotation of the humeral head on the glenoid. However, limited understanding exists of the consequences associated with disruption of the AP force balance (due to tears of both the supraspinatus and infraspinatus tendons) on joint function and joint damage. We investigated the effect of disrupting the APforce balance on joint function and joint damage in an overuse rat model. Twenty-eight rats underwent 4 weeks of overuse to produce a tendinopathic condition and were then randomized into two surgical groups: Detachment of the supraspinatus only or detachment of the supraspinatus and infraspinatus tendons. Rats were then gradually returned to their overuse protocol. Quantitative ambulatory measures including medial/lateral, propulsion, braking, and vertical forces were significantly different between groups. Additionally, cartilage and adjacent tendon properties were significantly altered. These results identify joint imbalance as a mechanical mechanism for joint damage and demonstrate the importance of preserving rotator cuff balance when treating active cuff tear patients.

Background Interest in outpatient total hip arthroplasty (THA) and total knee arthroplasty (TKA) has increased recently as part of value-based care and early recovery protocols. Outpatient pathways require significant paradigm shifts, are not used widely, and are mostly implemented at outpatient surgery centers or orthopedic specialty hospitals. In this article, we report on the outcomes of implementation of an outpatient arthroplasty protocol at a tertiary care academic medical center. Methods We performed a retrospective review on a series of 105 consecutive patients who underwent THA or TKA following our newly implemented outpatient arthroplasty protocol. We compared these patients to a group of inpatient arthroplasty patients from the same time period. Results Eighty-three of 105 (79%) patients were successfully discharged home on the day of surgery. Successful same-day discharge was predicted by early ambulation ( P = .01), TKA over THA ( P = .04), and shorter duration of surgery ( P = .01). General anesthesia correlated with better early ambulation distances ( P = .03) and a lower incidence of urinary retention ( P = .049). The outpatient readmission and complication rates were 0.95% and 1.9%, respectively, whereas the matched inpatient rates were 3.7% and 2.9%, respectively. Conclusions Outpatient THA and TKA in a well-selected patient is feasible in an academic multidisciplinary tertiary care hospital, with complication rates approximating inpatient surgery. The findings reported here can be used to further optimize outpatient arthroplasty protocols.

BackgroundTotal joint arthroplasty (TJA) remains the highest expenditure in the Centers for Medicare and Medicaid Services (CMS) budget. One model to control cost is the Comprehensive Care for Joint Replacement (CJR) model. There has been no published literature to date examining the efficacy of CJR on value-based outcomes. The purpose of this study was to determine the efficacy and sustainability of a multidisciplinary care redesign for total joint arthroplasty under the CJR paradigm at an academic tertiary care center.MethodsWe implemented a system-wide care redesign, affecting all patients who underwent a total hip or total knee arthroplasty at our academic medical center. The main study outcomes were cost (to CMS), discharge destination, complications and readmissions, and length of stay (LOS); these were measured using the 2017 initial CJR reconciliation report, as well as our institutional database.ResultsThe study included 1536 patients (41% Medicare). Per-episode cost to CMS declined by 19.5% to 11% below the CMS-designated national target. Home discharge increased from 62% to 87%. CMS readmissions declined from 15% to 6%; major complications decreased from 2.3% to 1.9%; and LOS declined from 3.6 to 2.1 days.ConclusionsA mandatory episode-based bundled-payment program can induce favorable changes to value-based metrics, improving quality and outcomes for health-care consumers. Quality and value were improved in this study, evidenced by lower 90-day episode cost, more home discharges, lower readmissions and complications, and shorter LOS. This approach has implications not just for CMS, but for private payers, corporate health programs, and fixed-budget health-care models.

Purpose: Cytochrome P450 2D6 ( CYP2D6) genotype-guided opioid prescribing is limited. The purpose of this type 2 hybrid implementation-effectiveness trial was to evaluate the feasibility of clinically implementing CYP2D6-guided post-surgical pain management and determine that such an approach did not worsen pain control. Methods: Adults undergoing total joint arthroplasty were randomized 2:1 to genotype-guided or usual pain management. For participants in the genotype-guided arm with a CYP2D6 poor (PM), intermediate (IM), or ultra-rapid metabolizer (UM) phenotype, recommendations were to avoid hydrocodone, tramadol, codeine, and oxycodone. The primary endpoints were feasibility metrics and opioid use; pain intensity was a secondary endpoint. Effectiveness outcomes were collected 2-weeks post-surgery. Results: Of 282 patients approached, 260 (92%) agreed to participate. In the genotype-guided arm, 20% had a high-risk (IM/PM/UM) phenotype, of whom 72% received an alternative opioid versus 0% of usual care participants (p<0.001). In an exploratory analysis, there was less opioid consumption (200 [104-280] vs. 230 [133-350] morphine milligram equivalents; p=0.047) and similar pain intensity (2.6 ± 0.8 vs. 2.5 ± 0.7; p=0.638) in the genotype-guided vs. usual care arm, respectively. Conclusion: Implementing CYP2D6 to guide post-operative pain management is feasible and may lead to lower opioid use without compromising pain control.

Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.