Generation of 5-Strand Hamstring Autograft for Anterior Cruciate Ligament Reconstruction-A Technical Note.

Hamstring tendons are a very commonly used autograft for anterior cruciate ligament (ACL) reconstruction. Given that larger hamstring graft diameter has been shown to positively affect outcomes after ACL reconstruction, several techniques have been developed to optimize this variable. In this technical note, we describe the operative technique for generation of a 5-strand hamstring autograft via tripling of the semitendinosus tendon and doubling of the gracilis tendon, which can serve to maximize graft diameter, especially in patient populations with undersized hamstring tendons at baseline.

Multi-domain biopsychosocial postoperative recovery trajectories associate with patient outcomes following lumbar fusion.

PURPOSE: The purpose of this study is to describe and assess the impact of multi-domain biopsychosocial (BPS) recovery on outcomes following lumbar spine fusion. We hypothesized that discrete patterns of BPS recovery (e.g., clusters) would be identified, and then associated with postoperative outcomes and preoperative patient data. METHODS: Patient-reported outcomes for pain, disability, depression, anxiety, fatigue, and social roles were collected at multiple timepoints for patients undergoing lumbar fusion between baseline and one year. Multivariable latent class mixed models assessed composite recovery as a function of (1) pain, (2) pain and disability, and (3) pain, disability, and additional BPS factors. Patients were assigned to clusters based on their composite recovery trajectories over time. RESULTS: Using all BPS outcomes from 510 patients undergoing lumbar fusion, three multi-domain postoperative recovery clusters were identified: Gradual BPS Responders (11%), Rapid BPS Responders (36%), and Rebound Responders (53%). Modeling recovery from pain alone or pain and disability alone failed to generate meaningful or distinct recovery clusters. BPS recovery clusters were associated with number of levels fused and preoperative opioid use. Postoperative opioid use (p < 0.01) and hospital length of stay (p < 0.01) were associated with BPS recovery clusters even after adjusting for confounding factors. CONCLUSION: This study describes distinct clusters of recovery following lumbar spine fusion derived from multiple BPS factors, which are related to patient-specific preoperative factors and postoperative outcomes. Understanding postoperative recovery trajectories across multiple health domains will advance our understanding of how BPS factors interact with surgical outcomes and could inform personalized care plans.

#OrthoTwitter: Relationship Between Author Twitter Utilization and Academic Impact in Orthopaedic Surgery.

Background #OrthoTwitter has evolved to disseminate findings and engage the public. However, the academic impact of Twitter utilization in orthopaedic surgery is unknown. Questions/purposes The purpose of the study was to evaluate relationships between the author and manuscript Twitter activity and citations. Methods Manuscripts in 17 orthopaedic journals from 2018 were identified. Citations, online mentions, impact factors, and subspecialties were obtained. H-index and Twitter account details for authors were obtained for a subset of manuscripts. Relationships between Twitter activity and citations were evaluated. Results 2,473/4,224 (58.5%) manuscripts were mentioned on Twitter (n=29,958 mentions), with Twitter manuscripts cited more frequently (median 10 vs. 7, p<0.0001). Twitter mentions, impact factors, non-open-access status, and subspecialties were associated with citation counts. Articles mentioned in 10, 100, and 1,000 Tweets were observed to have a 1.1-fold, 1.7-fold, and 245-fold increase in citations. In author-level analyses, 156 (20.0%) first and 216 (27.7%) senior authors had Twitter accounts. Citation count was associated with increasing senior author H-index (ß est=0.13, p<0.05), Twitter mentions (ß est=0.0043, p<0.0001), impact factors (ß est=0.13, p<0.0001), and having a first (ß est=0.20, p<0.05) or senior author (ß est=0.17, p<0.05) on Twitter. Articles published in arthroplasty (ß est=0.49, p<0.05), general interest (ß est=0.55, p<0.01), sports (ß est=0.63, p<0.01), and non-open access journals (ß est=0.41, p<0.001) were cited more. H-index correlated with followers for first (rho=0.31, p<0.0001) and senior authors (rho=0.44, p<0.0001). Conclusion Author Twitter utilization is independently associated with manuscript citations. Authors should be aware of the potential association between social media utilization and traditional academic impact. Understanding the relationship between social media utilization and academic impact is necessary to effectively disseminate research.

Interobserver and Intraobserver Reliability of Classification Systems for Radiographic Complications After Radial Head Arthroplasty.

PURPOSE: Although several classifications are used to assess radiographs following radial head arthroplasty (RHA), including the Popovic classification for radiolucency, the Chanlalit classification for stress shielding (SS), the Brooker classification for heterotopic ossification (HO), and the Broberg-Morrey classification for radiocapitellar arthritis, little is known about the reliability of these classification systems. The purpose of this study was to determine the interobserver and intraobserver reliability of these classifications. METHODS: Six orthopedic surgeons at various levels of training reviewed elbow radiographs of 20 patients who underwent RHA and classified them according to the Popovic, Chanlalit, Brooker, and Broberg-Morrey classifications for radiolucency, SS, HO, and RHA, respectively. Four weeks after initial review, radiographic reviews were repeated. Reliability was measured using the Fleiss kappa and the intraclass correlation coefficient. Agreement was interpreted as none (<0), slight (0.01-0.2), fair (0.21-0.4), moderate (0.41-0.6), substantial (0.61-0.8), and almost perfect (0.81-1) based on agreement among attending surgeons. RESULTS: Among fellowship-trained attending surgeons, interobserver reliability was slight for SS (Chanlalit) and the categorical interpretation of radiolucency (Popovic), fair for radiocapitellar arthritis (Broberg-Morrey) and HO (Brooker), and substantial for the ordinal interpretation of radiolucency (Popovic). Residents had a higher interobserver reliability than attending physicians when using the Brooker classification. Mean intraobserver reliability was fair for SS (Chanlalit) and the categorical interpretation of radiolucency (Popovic), moderate for HO (Brooker) and radiocapitellar arthritis (Broberg-Morrey), and almost perfect for the ordinal interpretation of radiolucency (Popovic). Trainees had higher intraobserver reliability than attending surgeons using the SS (Chanlalit) classification. CONCLUSIONS: The number of Popovic zones is reliable for communication between physicians, but caution should be taken with the Brooker, Chanlalit, Broberg-Morrey, and categorical interpretation of the Popovic classifications. All the classifications had better intraobserver than interobserver reliability. CLINICAL RELEVANCE: Reliability of classification systems for radiographic complications after RHA is less than substantial except the number of zones of radiolucency; therefore, caution is required when drawing conclusions based on these classifications.

Incidence of Venous Thromboembolism After Hip Arthroscopy Is Low With or Without Prophylaxis but Risk Factors Include Oral Contraceptive Use, Obesity, and Malignancy.

PURPOSE: To determine the incidence of and risk factors for symptomatic venous thromboembolism (VTE) after hip arthroscopy (HA) and thromboprophylaxis prescription utilization for this procedure. METHODS: The PearlDiver Mariner database was queried using Current Procedural Terminology codes to identify adult patients (aged ≥ 18 years) who underwent HA between 2010 and 2020. Patient demographic information, including age, oral contraceptive use, and medical comorbidities, as well as perioperative thromboprophylaxis utilization, was recorded using International Classification of Diseases codes and National Drug Codes. The incidence of postoperative VTE within 90 days was determined. Multivariate logistic regression was used to identify predictors of perioperative thromboprophylaxis utilization and risk factors for VTE. RESULTS: The queried records identified 60,181 patients who met the inclusion criteria. Of these patients, 367 (0.6%) experienced VTE, including deep venous thrombosis (0.5%) and/or pulmonary embolism (0.2%). Approximately 2.1% of patients used thromboprophylaxis, including aspirin (1.1%), low-molecular-weight heparin (0.9%), and oral factor Xa inhibitors (0.1%). Oral contraceptive pill use (adjusted odds ratio [aOR], 2.16; 95% confidence interval [CI], 1.34-3.46), obesity (aOR, 1.37; 95% CI, 1.05-1.79), and a history of malignancy (aOR, 1.69; 95% CI, 1.12-2.54) were associated with increased odds of experiencing VTE. Perioperative thromboprophylaxis (aOR, 0.52; 95% CI, 0.19-1.39) was not significantly associated with decreased odds of experiencing VTE. However, obesity (aOR, 1.17; 95% CI, 1.00-1.38) and hypertension (aOR, 1.17; 95% CI, 1.02-1.36) were associated with increased odds of thromboprophylaxis prescription utilization. CONCLUSIONS: Although the overall risk of symptomatic VTE after HA remains low, oral contraceptive use, obesity, and a history of malignancy are associated with increased odds of thromboembolic events within 90 days. Routine thromboprophylaxis after HA may not be indicated in all patients but can be considered based on patient-specific risk factors. LEVEL OF EVIDENCE: Level III, retrospective prognostic comparative trial.

Extensor Mechanism Reconstruction Using Achilles Tendon Allograft With Suture Tape Augmentation.

The management of chronic extensor mechanism injuries represents a significant challenge for orthopaedic surgeons, with numerous options for graft choice and fixation construct, but no clear consensus on which technique achieves optimal outcomes. Although there is little published data regarding outcomes of different fixation methods, small case series have demonstrated modest success using Achilles tendon bone block allografts and transverse patellar screw fixation. In this technical note, we describe a surgical technique for the treatment of a chronic inferior pole patella fracture, with extensor mechanism reconstruction using an Achilles tendon allograft with suture tape augmentation. Our technique describes the use of vertical cannulated screws in the patella for passing tape augmentation sutures, increased construct security by suturing of the Achilles graft directly to the quadriceps tendon, and the use of a post screw in the proximal tibia for suture tape augmentation.

Management of Displaced Midshaft Clavicle Fractures in Pediatrics and Adolescents: Operative vs Nonoperative Treatment.

The purpose of the current review is to describe the management of displaced midshaft clavicle fractures in pediatric and adolescent patients. Midshaft clavicle fractures are relatively common in pediatric and adolescent patients. They most commonly occur from direct trauma and are often related to sports participation in adolescents. Recent literature in the management of adult midshaft clavicle fractures has supported operative management due to improved functional outcomes, decreased time to union, leading to early return to activity. A similar trend of increasing frequency in operative management has been seen in pediatric and adolescent patients with no consensus in the literature on optimal management. Nonoperative treatment consists of with a brief period of sling immobilization followed by range of motion. Operative management may be considered for open fractures, fractures with significant neurovascular compromise and soft tissue complications. Studies have shown comparable mid- to long-term functional and patient-reported outcomes after operative and nonoperative management of midshaft clavicle fractures in pediatric patients.

Perioperative Thromboprophylaxis Is Associated With Lower Risk of Venous Thromboembolism After Knee Arthroscopy.

PURPOSE: To determine the rate of symptomatic venous thromboembolism (VTE) among patients undergoing arthroscopic knee procedures, risk factors associated with postoperative VTE, and current perioperative thromboprophylaxis prescription patterns associated with this population in the United States. METHODS: Medical records for patients ≥18 years of age were queried from the Mariner database using Current Procedural Terminology codes for knee arthroscopy performed in the United States from 2010 to 2020 in this cross-sectional study. Patients who received thromboprophylaxis and those diagnosed with VTE, including deep-vein thrombosis or pulmonary embolism, within 90 days of surgery were identified using International Classification of Diseases and National Drug Codes. Two multivariable logistic regression models were used to identify VTE risk factors and likelihood of perioperative thromboprophylaxis. Covariates included procedure type, age, oral contraceptive pill (OCP) use, and medical comorbidities. RESULTS: A total of 718,289 patients met inclusion criteria and 7,618 patients (1.06%) experienced VTE, including deep-vein thrombosis (n = 6,394, 0.9%) and/or pulmonary embolism (n = 2,211, 0.3%). A total of 10,769 patients (1.5%) filled perioperative thromboprophylaxis, including aspirin (n = 5,353, 0.7%), low-molecular-weight heparin (n = 4,563, 0.6%), and oral factor Xa inhibitors (n = 947, 0.1%). Perioperative thromboprophylaxis was associated with decreased odds of experiencing VTE (adjusted odds ratio [aOR] 0.65, 95% confidence interval [CI] 0.51-0.80). Procedure types categorized as moderate-to-greater risk were associated with increased odds of VTE (aOR 1.42, 95% CI 1.34-1.50). OCP use (aOR 1.63, 95% CI 1.38-1.91), obesity (aOR 1.17, 95% CI 1.11-1.24), renal disease (aOR 1.33, 95% CI 1.18-1.50) and congestive heart failure (aOR 1.30, 95% CI 1.13-1.50) were associated with increased odds of VTE. CONCLUSIONS: While the overall rate of symptomatic VTE following knee arthroscopy remains low, procedure types that are more complex and generally require restrictive rehabilitation protocols, OCP use, obesity, renal disease, and congestive heart failure are associated with increased odds of postoperative VTE. Conversely, the use of perioperative thromboprophylaxis is associated with significantly lower VTE risk. LEVEL OF EVIDENCE: III, retrospective comparative prognostic trial.

Association of Insurance Status With Treatment Delays for Pediatric and Adolescent Patients Undergoing Surgery for Patellar Instability.

Background: Health care disparities have been highlighted in pediatric sports medicine, but the association between insurance status and delayed care for patients undergoing surgery for patellar instability has not been defined. Purpose: To determine whether there is an association between insurance status and delays in care in pediatric and adolescent patients undergoing surgery for patellar instability. Study Design: Cohort study; Level of evidence, 3. Methods: This was a retrospective case series at a safety-net tertiary referral center of pediatric and adolescent patients undergoing surgical treatment for patellar instability. Insurance status was classified as public or private. We calculated the times from injury to clinical evaluation, injury to magnetic resonance imaging (MRI), injury to surgery, clinical evaluation to MRI, and clinical evaluation to surgery. Comparisons were made between insurance groups. Results: Included were 78 patients (38 public, 40 private insurance) who underwent surgery for patellar instability. The public insurance group was older (P = .019), with a lower proportion of White patients (15.8% vs 52.5%; P = .0005), higher proportion with Hispanic ethnicity (55.3% vs 15.0%; P = .0001), and higher proportion of Spanish-speaking patients (21.1% vs 2.5%; P = .007). Publicly insured patients had longer times from initial injury to clinical evaluation (466 vs 77 days; P = .002), MRI (466 vs 82 days; P = .003), and surgery (695 vs 153 days; P = .0003), as well as a longer time from clinical evaluation to surgery (226 vs 73 days; P = .002). Multivariable models confirmed insurance status as an independent predictor in each of the identified delays. Conclusion: Significant delays were seen for pediatric and adolescent patients with patellar instability and public insurance (approximately 6 times longer to clinical evaluation, more than 5.5 times longer to obtain MRI, and 4.5 times longer to surgery) relative to injured patients with private insurance. Even after adjusting for delays to clinical evaluation, publicly insured patients had a delay from clinic to surgery that was triple that of privately insured patients.

Point-of-care motion capture and biomechanical assessment improve clinical utility of dynamic balance testing for lower extremity osteoarthritis.

Musculoskeletal conditions impede patient biomechanical function. However, clinicians rely on subjective functional assessments with poor test characteristics for biomechanical outcomes because more advanced assessments are impractical in the ambulatory care setting. Using markerless motion capture (MMC) in clinic to record time-series joint position data, we implemented a spatiotemporal assessment of patient kinematics during lower extremity functional testing to evaluate whether kinematic models could identify disease states beyond conventional clinical scoring. 213 trials of the star excursion balance test (SEBT) were recorded by 36 subjects during routine ambulatory clinic visits using both MMC technology and conventional clinician scoring. Conventional clinical scoring failed to distinguish patients with symptomatic lower extremity osteoarthritis (OA) from healthy controls in each component of the assessment. However, principal component analysis of shape models generated from MMC recordings revealed significant differences in subject posture between the OA and control cohorts for six of the eight components. Additionally, time-series models of subject posture change over time revealed distinct movement patterns and reduced overall postural change in the OA cohort compared to the controls. Finally, a novel metric quantifying postural control was derived from subject specific kinematic models and was shown to distinguish OA (1.69), asymptomatic postoperative (1.27), and control (1.23) cohorts (p = 0.0025) and to correlate with patient-reported OA symptom severity (R = -0.72, p = 0.018). Time series motion data have superior discriminative validity and clinical utility than conventional functional assessments in the case of the SEBT. Novel spatiotemporal assessment approaches can enable routine in-clinic collection of objective patient-specific biomechanical data for clinical decision-making and monitoring recovery.

Patient outcomes and costs after isolated flexor tendon repairs of the hand.

BACKGROUND: Acute flexor tendon injuries are challenging injuries for patients, surgeons, and therapists alike. There is ongoing debate about the optimal timing and amount of therapy after these injuries. PURPOSE: We sought to investigate the relationship between hand therapy utilization and reoperation rates after flexor tendon repair and quantify reoperation rates and costs associated with flexor tendon repair. We hypothesize there will be an inverse relationship between the number of hand therapy visits and later reoperation rates and a positive correlation between reoperation rates and total cost of care. STUDY DESIGN: A retrospective cohort study of patients undergoing primary flexor tendon repair was pursued. METHODS: A commercially available database was utilized to access insurance claims data for 20.9 million patients in the US from 2007 to 2015. Patients undergoing primary flexor tendon repair were included and followed for one year. Patients with fractures, vascular injuries, or digit replantation were excluded. We studied post-operative rehabilitation utilization, reoperation rates, and costs. Chi-Square tests and multivariable logistic regressions were used to assess the relationship between therapy utilization and reoperation rates and costs. RESULTS: The one-year reoperation rate was 11.4 percent at a median time of 100.0 days amongst 1,129 patients undergoing primary tendon repair. In multivariable analysis, age between 30 and 59, male sex, and utilization of over 21 therapy sessions were associated with increased odds of reoperation. Mean insurance reimbursement one year following primary flexor repair was $14,533 per patient but $27,870 if patients went on to reoperation. CONCLUSION: Continued therapy utilization after primary flexor tendon repair is an independent predictor of reoperation need. These findings may help surgeons counsel patients who require a large number of visits after flexor tendon repair on when to revisit surgical options.

Opioid Use following Open versus Endoscopic Carpal Tunnel Release: A Population Study.

Open (OCTR) and endoscopic carpal tunnel release (ECTR) are both effective treatments for carpal tunnel syndrome, with similar outcomes and complication rates. Given the opioid epidemic, it is important to consider how surgical modality impacts narcotic use. We compared narcotic use after OCTR and ECTR to identify trends and risk factors for prolonged postoperative use. METHODS: We utilized the PearlDiver database to identify patients who underwent OCTR and ECTR between 2008 and 2015. Patients with opioid use were analyzed for trends. Early refills, prolonged postoperative opioid use, and new persistent opioid use were defined by time periods relating to the date of surgery. Age, gender, Charlson comorbidity index (CCI), and surgery type (open versus endoscopic) were analyzed as predictors for opioid use. RESULTS: A total of 29,583 patients were included: 4125 (14%) ECTR and 25,458 (86%) OCTR. Significantly more OCTR patients filled perioperative prescriptions (62% versus 60%), and the OCTR group filled higher quantities of perioperative opioids (411 OME versus 379 OME). Patients in the OCTR group were also significantly more likely to obtain early refills and to have prolonged postoperative use. There was no difference in the rate of new persistent use. CONCLUSIONS: Compared with ECTR, patients who underwent OCTR filled higher quantities of opioids in the perioperative period, were more likely to obtain early refills, and were more likely to have prolonged postoperative use. These findings suggest either a lower opioid requirement after ECTR or a lower perceived requirement reflected in the difference in prescribing habits between techniques.

Predictors of a change in patient willingness to have Total knee arthroplasty: Insights from the osteoarthritis initiative.

BACKGROUND: While many factors have been shown to influence patient willingness to have total joint arthroplasty, factors associated with changes in patient willingness to have arthroplasty have not been studied. The objective of this research is to identify predictors of change in patient willingness to have total knee arthroplasty (TKA). METHODS: Patient willingness to have TKA as well as questionnaire, clinical, and radiographic data, were obtained from the Osteoarthritis Initiative (OAI) for individuals with, or at high risk for developing knee OA. Mixed effects ordinal logistic regressions were employed to assess the relationships between 40 predictors and change in willingness to have surgery. Predictors significant in univariate models were included in a multivariable analysis. RESULTS: Three thousand three hundred and ninety-four OAI patients were included in our analysis. Between baseline and follow-up, 462 (13.6%) became more willing and 533 (15.7%) became less willing to have TKA. After controlling for demographic factors in multivariable analysis, patients with higher income and expected difficulty with postoperative walking were more likely to increase their willingness to have TKA. General health, race, and knee injections within the past six months approached significance with regard to increasing willingness to have TKA over time. CONCLUSION: Income and expectations of difficulty walking postoperatively were significantly associated with changes in patient willingness to have TKA independent of age, sex, health coverage, employment, marriage status, and knee pain. Understanding factors influencing patient willingness to have surgery may be instrumental in counseling and addressing the mismatch of OA disease burden to surgical utilization.

Wide-Awake Local Anesthesia for Minor Hand Surgery Associated With Lower Opioid Prescriptions, Morbidity, and Costs: A Nationwide Database Study.

Purpose: We sought to investigate the perioperative opioid prescription patterns, complication rates, and costs associated with wide-awake local anesthesia (WALA) techniques using a nationwide insurance claims-based database. Methods: We used the PearlDiver Humana administrative claims database to identify opioid-naive adult patients who underwent a carpal tunnel release, trigger finger release, or de Quervain release between 2007 and 2015. Patients were divided into WALA and standard anesthesia groups by the presence or absence of anesthesia Current Procedural Terminology codes. We evaluated for differences in perioperative opioid prescribing patterns, rates of opioid refills, and insurance reimbursement. The incidence of surgical complications and medical complications within 30 days of surgery were determined by International Classification of Diseases, Ninth Revision codes. Adjusted odds ratios were calculated with multivariable logistic regression models to identify factors associated with filling or refilling opioid prescriptions and complication rates. Results: There were 6,285 patients in the WALA group and 28,657 in the standard anesthesia group. The WALA patients were prescribed significantly lower quantities of opioids than were standard anesthesia patients across all 3 procedures. After controlling for type of surgery, gender, and comorbidities in a multivariate model, WALA patients were less likely to fill an initial opioid prescription during the perioperative period but were equally likely to obtain a refill. The WALA patients had lower odds of developing both surgical and medical complications compared with standard anesthesia patients. Moreover, WALA was associated with significantly lower costs for all procedures. Conclusions: Wide-awake local anesthesia technique is an increasingly common and viable option for minor hand surgery. It is a cost-effective and safe technique for simple hand surgical procedures and can be a strategy to minimize postoperative opioid use. Type of study/level of evidence: Prognostic II.

Scientific Quality of Health-Related Articles in Specialty Cannabis and General Newspapers in San Francisco.

Recreational cannabis is being legalized in states across the USA. The public relies on popular media for health information about cannabis. We assessed the accuracy of reporting on health effects of cannabis use in GreenState, a specialty publication on cannabis published by the San Francisco Chronicle and the main newspaper using the Index of Scientific Quality for Health Related News Reports. Results were compared using t-tests. Seventeen GreenState articles and four San Francisco Chronicle articles were identified for analysis. Health articles in GreenState scored 2.9 (±1.1 [SD]) Global, with the highest scoring category Applicability (4.5 ± 0.4) and the lowest Precision (2.4 ± 1.0) on a scale of 1-5. In contrast, the San Francisco Chronicle articles received a Global rating of 4.6 (±0.2), ranging from Applicability (5.0 ± 0) to Benefits (3.8 ± 0.9). Articles in the San Francisco Chronicle scored significantly higher in all categories but Benefits which was not significantly different for the San Francisco Chronicle compared with GreenState (3.8 vs. 3.6, p = 0.77). The public, clinicians, and policymakers need to be aware of this pattern and treat information in publications like GreenState with an appropriate level of skepticism until the quality of reporting improves to general journalistic standards.

Automated fabrication of photopatterned gelatin hydrogels for organ-on-chips applications.

Organ-on-chip platforms aim to improve preclinical models for organ-level responses to novel drug compounds. Heart-on-a-chip assays in particular require tissue engineering techniques that rely on labor-intensive photolithographic fabrication or resolution-limited 3D printing of micropatterned substrates, which limits turnover and flexibility of prototyping. We present a rapid and automated method for large scale on-demand micropatterning of gelatin hydrogels for organ-on-chip applications using a novel biocompatible laser-etching approach. Fast and automated micropatterning is achieved via photosensitization of gelatin using riboflavin-5'phosphate followed by UV laser-mediated photoablation of the gel surface in user-defined patterns only limited by the resolution of the 15 µm wide laser focal point. Using this photopatterning approach, we generated microscale surface groove and pillar structures with feature dimensions on the order of 10-30 µm. The standard deviation of feature height was 0.3 µm, demonstrating robustness and reproducibility. Importantly, the UV-patterning process is non-destructive and does not alter gelatin micromechanical properties. Furthermore, as a quality control step, UV-patterned heart chip substrates were seeded with rat or human cardiac myocytes, and we verified that the resulting cardiac tissues achieved structural organization, contractile function, and long-term viability comparable to manually patterned gelatin substrates. Start-to-finish, UV-patterning shortened the time required to design and manufacture micropatterned gelatin substrates for heart-on-chip applications by up to 60% compared to traditional lithography-based approaches, providing an important technological advance enroute to automated and continuous manufacturing of organ-on-chips.