OBJECTIVE:Surgical site complications (SSCs) are the leading cause of unplanned emergency department visits and readmissions following total joint arthroplasty (TJA). The use of closed-incision negative pressure therapy (ciNPT) has shown promise in reducing SSC occurrence. However, no study has evaluated the cost-effectiveness of ciNPT in primary TJA. The purpose of this study was to calculate the break-even absolute risk reduction (ARR) of SSCs, the break-even treatment cost of SSCs, and the break-even cost-of-use for ciNPT, based on existing literature to assess the cost-effectiveness of ciNPT in primary TJA. METHOD:Relevant values for ARR, infection treatment cost and intervention cost were obtained via literature review. A break-even analysis was conducted to investigate the cost-effectiveness of ciNPT use in primary TJA, as well as to derive the ARR, infection treatment cost (Ct) and intervention protocol cost (Cp) values at which ciNPT use becomes cost-effective. RESULTS:The values derived from the literature review were as follows: Cp=$160.76 USD; Ct=$5348.78 USD; ARR=0.0375. The break-even ARR was calculated to be 3.0%, the break-even Cp was calculated to be $200.58 USD, and the break-even Ct was calculated to be $4286.93 USD. The ARR of ciNPT use was greater than the calculated break-even ARR. CONCLUSION:This analysis demonstrated that ciNPT use in primary TJA was cost-effective. By examining the difference between the calculated break-even Cp and the Cp reported in the literature, the cost saved per patient treated with ciNPT can be calculated to be $39.82 USD.

Rotator cuff injuries result in more than 500,000 surgeries annually in the United States, many of which fail. These surgeries typically involve repair of the injured tendon and removal of the subacromial bursa, a synovial-like tissue that sits between the rotator cuff and the acromion. The subacromial bursa has been implicated in rotator cuff pathogenesis and healing. Using proteomic profiling of bursa samples from nine patients with rotator cuff injury, we show that the bursa responds to injury in the underlying tendon. In a rat model of supraspinatus tenotomy, we evaluated the bursa’s effect on the injured supraspinatus tendon, the uninjured infraspinatus tendon, and the underlying humeral head. The bursa protected the intact infraspinatus tendon adjacent to the injured supraspinatus tendon by maintaining its mechanical properties and protected the underlying humeral head by maintaining bone morphometry. The bursa promoted an inflammatory response in injured rat tendon, initiating expression of genes associated with wound healing, including Cox2 and Il6 . These results were confirmed in rat bursa organ cultures. To evaluate the potential of the bursa as a therapeutic target, polymer microspheres loaded with dexamethasone were delivered to the intact bursae of rats after tenotomy. Dexamethasone released from the bursa reduced Il1b expression in injured rat supraspinatus tendon, suggesting that the bursa could be used for drug delivery to reduce inflammation in the healing tendon. Our findings indicate that the subacromial bursa contributes to healing in underlying tissues of the shoulder joint, suggesting that its removal during rotator cuff surgery should be reconsidered.

Despite the relatively high frequency of Achilles ruptures, there is no general consensus on the optimal treatment method. A general trend toward more patients being treated nonoperatively has emerged recently with the advent of functional rehabilitation. However, much of the recent data on this subject has been highly variable. This systematic review focused on Achilles tendon rupture (ATR) treatment outcomes, with a focus on rerupture and complication rates. This systematic review specifically focused on articles regarding ATR treatment that also included rerupture and complication rates. Treatments were divided into three categories: open minimally invasive, open standard, and nonoperative. Bivariate analyses were performed to compare complication and rerupture rates among pairs of treatment options, as well as between early weight bearing versus immobilization. There was significantly higher complications for minimally invasive compared to nonoperative treatment (risk ratio [RR] = 4.4154; p < 0.05), lower complication rates for minimally invasive compared to open treatment (RR = 0.3231; p < 0.05), and higher complications for open standard compared to nonoperative treatment (RR = 5.6350; p < 0.001). There were significantly lower rerupture rates in minimally invasive compared to nonoperative treatment (RR = 0.4085; p < 0.001), a significantly lower rerupture rate in nonoperative treatment compared to open treatment (RR = 0.2282; p < 0.001), and no significant difference in rerupture rates when comparing minimally invasive to open standard treatment. We found that operative treatment is associated with fewer reruptures and more complications than a nonoperative approach. Minimally invasive surgery appears to be associated with a lower rate of complications than open operative treatment.

Rotator cuff injuries result in over 500,000 surgeries performed annually, an alarmingly high number of which fail. These procedures typically involve repair of the injured tendon and removal of the subacromial bursa. However, recent identification of a resident population of mesenchymal stem cells and inflammatory responsiveness of the bursa to tendinopathy indicate an unexplored biological role of the bursa in the context of rotator cuff disease. Therefore, we aimed to understand the clinical relevance of bursa-tendon crosstalk, characterize the biologic role of the bursa within the shoulder, and test the therapeutic potential for targeting the bursa. Proteomic profiling of patient bursa and tendon samples demonstrated that the bursa is activated by tendon injury. Using a rat to model rotator cuff injury and repair, tenotomy-activated bursa protected the intact tendon adjacent to the injured tendon and maintained the morphology of the underlying bone. The bursa also promoted an early inflammatory response in the injured tendon, initiating key players in wound healing. In vivo results were supported by targeted organ culture studies of the bursa. To examine the potential to therapeutically target the bursa, dexamethasone was delivered to the bursa, prompting a shift in cellular signaling towards resolution of inflammation in the healing tendon. In conclusion, contrary to current clinical practice, the bursa should be retained to the greatest extent possible and provides a new therapeutically target for improving tendon healing outcomes.One Sentence Summary:The subacromial bursa is activated by rotator cuff injury and regulates the paracrine environment of the shoulder to maintain the properties of the underlying tendon and bone.

BACKGROUND:Rotator cuff repair is a common orthopaedic procedure, yet the rate of failure to heal after surgery is high. Repair site rupture is due to poor tendon-to-bone healing and lack of regeneration of the native fibrocartilaginous enthesis. During development, the enthesis is formed and mineralized by a pool of progenitors activated by hedgehog signaling. Furthermore, hedgehog signaling drives regenerative enthesis healing in young animals, in contrast to older animals, in which enthesis injuries heal via fibrovascular scar and without participation of hedgehog signaling. HYPOTHESIS:Hedgehog activation improves tendon-to-bone healing in an animal model of rotator cuff repair. STUDY DESIGN:Controlled laboratory study. METHODS:A total of 78 adult Sprague-Dawley rats were used. Supraspinatus tendon injury and repair were completed bilaterally, with microsphere-encapsulated hedgehog agonist administered to right shoulders and control microspheres administered to left shoulders. Animals were sacrificed after 3, 14, 28, or 56 days. Gene expression and histological, biomechanical, and bone morphometric analyses were conducted. RESULTS:At 3 days, hedgehog signaling pathway genes Gli1 (1.70; P = .029) and Smo (2.06; P = .0173), as well as Runx2 (1.69; P = .0386), a transcription factor of osteogenesis, were upregulated in treated relative to control repairs. At 14 days, transcription factors of tenogenesis, Scx (4.00; P = .041), and chondrogenesis, Sox9 (2.95; P = .010), and mineralized fibrocartilage genes Col2 (3.18; P = .031) and Colx (1.85; P = .006), were upregulated in treated relative to control repairs. Treatment promoted fibrocartilage formation at the healing interface by 28 days, with improvements in tendon-bone maturity, organization, and continuity. Treatment led to improved biomechanical properties. The material property strength (2.43 vs 1.89 N/m2; P = .046) and the structural property work to failure (29.01 vs 18.09 mJ; P = .030) were increased in treated relative to control repairs at 28 days and 56 days, respectively. Treatment had a marginal effect on bone morphometry underlying the repair. Trabecular thickness (0.08 vs 0.07 mm; P = .035) was increased at 28 days. CONCLUSION:Hedgehog agonist treatment activated hedgehog signaling at the tendon-to-bone repair site and prompted increased mineralized fibrocartilage production. This extracellular matrix production and mineralization resulted in improved biomechanical properties, demonstrating the therapeutic potential of hedgehog agonism for improving tendon-to-bone healing after rotator cuff repair. CLINICAL RELEVANCE:This study demonstrates the therapeutic potential of hedgehog agonist treatment for improving tendon-to-bone healing after rotator cuff injury and repair.

Hedgehog (Hh) signaling has been widely acknowledged to play essential roles in many developmental processes, including endochondral ossification and growth plate maintenance. Furthermore, a rising number of studies have shown that Hh signaling is necessary for tendon enthesis development. Specifically, the well-tuned regulation of Hh signaling during development drives the formation of a mineral gradient across the tendon enthesis fibrocartilage. However, aberrant Hh signaling can also lead to pathologic heterotopic ossification in tendon or osteophyte formation at the enthesis. Therefore, the therapeutic potential of Hh signaling modulation for treating tendon and enthesis diseases remains uncertain. For example, increased Hh signaling may enhance tendon-to-bone healing by promoting the formation of mineralized fibrocartilage at the healing interface, but pathologic heterotopic ossification may also be triggered in the adjacent tendon. Further work is needed to elucidate the distinct functions of Hh signaling in the tendon and enthesis to support the development of therapies that target the pathway.

PURPOSE:The purpose of this study was to evaluate the effect of intraoperative scrub nurse handoffs on surgical times for arthroscopically-assisted anterior cruciate ligament (ACL) reconstructions and hip arthroscopies.METHODS:A retrospective chart review was done at a major, urban academic medical center for all patients who underwent arthroscopically-assisted ACL reconstructions and hip arthroscopies for femoroacetabular impingement syndrome between May 2014 and May 2020. All ACL reconstructions were performed by 1 of 6 sports medicine fellowship-trained surgeons, and all hip arthroscopies were performed by a single surgeon. Operative times, number of scrub nurse handoffs, surgeon, patient demographics, and procedure-specific information were recorded. The association between patient characteristics and the number of handoffs, as well as the association between patient characteristics and operative times, stratified by scrub nurse handoffs, were calculated. A multivariable linear regression was performed to assess the association between intra-operative handoffs and operative times.RESULTS:Eight hundred twenty ACL reconstructions and 269 hip arthroscopies were identified. Multivariable linear regression demonstrated increasing intraoperative scrub nurse handoffs were associated with increased operative times for all patients. For ACL reconstructions, when including all possible covariates, 1 scrub nurse handoff increased operative times by 21.1 minutes (95% confidence interval [CI]: 15.36 to 26.89; P < .001), and 2+ handoffs increased operative times by 34.2 minutes (95% CI: 26.28 to 42.15; P < .001). For hip arthroscopies, 1 scrub nurse handoff increased operative times by 7.0 minutes (95% CI: 0.31 to 13.74; P = .04).CONCLUSION:Although a causal link cannot be made, intraoperative scrub nurse handoffs were associated with statistically significant increase in operative times for both ACL reconstructions and hip arthroscopies.LEVEL OF EVIDENCE:Level III, retrospective cohort study.

Calcium flowing through voltage-dependent calcium channels into cardiomyocytes mediates excitation-contraction coupling, controls action-potential duration and automaticity in nodal cells, and regulates gene expression. Proper surface targeting and basal and hormonal regulation of calcium channels are vital for normal cardiac physiology. In this review, we discuss the roles of voltage-gated calcium channels in the heart and the mechanisms by which these channels are regulated by physiological signaling pathways in health and disease.