CAS Common Chemistry in 2021: Expanding Access to Trusted Chemical Information for the Scientific Community.

CAS Common Chemistry (https://commonchemistry.cas.org/) is an open web resource that provides access to reliable chemical substance information for the scientific community. Having served millions of visitors since its creation in 2009, the resource was extensively updated in 2021 with significant enhancements. The underlying dataset was expanded from 8000 to 500,000 chemical substances and includes additional associated information, such as basic properties and computer-readable chemical structure information. New use cases are supported with enhanced search capabilities and an integrated application programming interface. Reusable licensing of the content is provided through a Creative Commons Attribution-Non-Commercial (CC-BY-NC 4.0) license allowing other public resources to integrate the data into their systems. This paper provides an overview of the enhancements to data and functionality, discusses the benefits of the contribution to the chemistry community, and summarizes recent progress in leveraging this resource to strengthen other information sources.

Intraoperative Subluxation of the Ulnar Nerve: Use of a Triceps Sling Reconstruction Technique.

PURPOSE: To determine whether the triceps sling reconstruction technique is a safe and effective treatment of intraoperative ulnar nerve subluxation after in situ decompression. METHODS: Twelve patients who underwent a triceps sling reconstruction for intraoperative ulnar nerve subluxation after in situ release were retrospectively reviewed. The triceps sling technique consists of harvesting a small, distally based strip of triceps tendon and suturing the proximal end of the strip to the posterior aspect of the released Osborne ligament. Thus, a sling is created between the medial epicondyle and the olecranon, preventing the nerve from subluxating. Patients were clinically evaluated before and after surgery. Visual analog scale pain scores, static 2-point discrimination, strength, and Disabilities of the Arm, Shoulder, and Hand score were assessed. RESULTS: At a mean follow-up of 31 months (range, 24-38 months), there was a significant improvement in mean visual analog pain scores from 8.6 to 0.2. Static 2-point discrimination was improved from a mean of 9.1 mm before surgery to 5.7 mm afterward. Strength improved by a mean of 33% and 30% with grip and pinch, respectively. Mean Disabilities of the Arm, Shoulder, and Hand score improved from 45.9 to 3.7. No subluxation of the ulnar nerve was noted after surgery. No other complications were noted. No reoperations were required during the follow-up period. CONCLUSIONS: Triceps sling reconstruction is a safe treatment in patients with intraoperative ulnar nerve subluxation after in situ decompression. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Fracture related ulnar and sciatic nerve transections: a report of two cases and literature review.

INTRODUCTION: Case reports, case series, and case control studies have looked at the incidence of complete nerve transection in the setting of fracture and the need for surgical exploration dating back to the 1920s. We present two cases of nerve laceration accompanying traumatic fracture with a thorough review of the literature. METHODS: We used the following search terms: "ulnar nerve" OR "sciatic nerve" AND "laceration" OR "transection" AND "fracture." Results were reviewed and included for discussion if they specifically reported ulnar or sciatic nerve laceration accompanying traumatic fracture. RESULTS: Our search yielded 15 papers reporting a total of 10 ulnar nerve lacerations and nine sciatic nerve lacerations. We present two additional cases. The first is a patient with a humerus fracture and complete ulnar nerve transection. The second case is a patient who suffered a femur fracture and complete transection of the sciatic nerve. CONCLUSION: Nerve laceration accompanying traumatic fracture is rare. We review the reported cases of nerve laceration and present two cases treated at our institution. Though uncommon, nerve laceration should be considered in the setting of traumatic fracture with neurological injury, particularly open fractures.

Effects of Medial Displacement Calcaneal Osteotomy and Calcaneal Z Osteotomy on Subtalar Joint Pressures: A Cadaveric Flatfoot Model.

Medial displacement calcaneal osteotomies have been shown to be successful in the surgical management of adult acquired flatfoot, in particular, stage 2 deformity. Classically, the medial displacement calcaneal osteotomy technique has been performed. However, a calcaneal Z osteotomy has been more recently described and applied in the surgical management of flatfoot deformity. Although the potential advantages of the calcaneal Z technique have been reported, data on its effect on the subtalar joint are lacking. A validated flatfoot model was induced in 8 cadaveric feet that had been randomly assigned to either medial displacement calcaneal osteotomy (n = 4) or calcaneal Z osteotomy (n = 4). The feet were loaded through the tibia with a constant ground reaction force of 400 N, with a simultaneous increase in the Achilles tendon force to 300 or 500 N. The subtalar joint pressures were recorded before and after osteotomy. We did not detect any statistically significant differences between the 2 techniques in terms of their effects on subtalar joint pressure.

PROMIS Measures in Patients with Ganglion Cysts: Who Chooses Surgical Excision Over Non-Operative Management?

Background: Ganglion cysts are common soft tissue masses of the hand and wrist. It is unclear why some patients pursue surgical excision and others do not. The objective of this study is to compare Patient-Reported Outcomes Measurement Information Systems (PROMIS) scores between patients with ganglion cysts undergoing surgical versus non-surgical treatment. Methods: Patients presenting to a tertiary, academic hand clinic diagnosed with a wrist ganglion cyst, based on clinical exam, were identified. PROMIS Physical Function (PF), Pain Interference (PI), and Depression scores at the time of diagnosis were reviewed. Data were then stratified according to surgical or non-surgical intervention, with subgroup analysis of dorsal versus volar ganglions and patients that chose to trial cyst aspiration. All results were compared utilizing the appropriate statistical methods. Results: Of 757 ganglion cyst patients, 264 underwent surgical excision and 493 were treated non-surgically. No difference was noted in PROMIS PF or Depression scores. However, the surgical cohort reported significantly increased preoperative PI scores (Table 2). A higher percentage of patients treated non-surgically received an aspiration attempt compared to those who ultimately received surgery (Table 3). Finally, patients with volar ganglion cysts had significantly increased PI and depression scores, as well as lower PF scores (Table 4). Conclusions: Presenting PROMIS PI may indicate an increased tendency to pursue surgical treatments and aid in the identification of ganglion cyst patients who are more likely to pursue surgical excision. Further research should focus on correlating absolute differences in PROMIS values with clinical significance.

Hand and Wrist Tendinopathies.

Tendinopathies in the hand and wrist are common in athletes. This article reviews some of the common hand and wrist conditions, such as trigger digits, first dorsal compartment tendonitis, and extensor carpi ulnaris tendonitis. In addition, it reviews less commonly seen tendon conditions of the flexor carpi radialis and ulnaris, intersection syndrome, and extensor pollicis entrapment conditions. Diagnosis, nonoperative and operative treatment, and postoperative recommendations and return to play are also discussed.

Biomechanical Stability of Volar Plate Only Versus Addition of Dorsal Ulnar Pin Plate: A Dorsal Ulnar Fragment, C-3-Type, Distal Radius, Cadaver Fracture Model.

OBJECTIVE: To determine if the addition of a dorsal ulnar pin plate provides improved stability characteristics in the management of intra-articular distal radius fractures with an associated dorsal ulnar fragment. METHODS: OTA/AO type C3 fractures, with a dorsal ulnar fragment of one-third or one-half the width of the distal radius, were simulated in 9 matched pairs of fresh-frozen cadaveric arms randomized between fixed-angle volar plate only versus volar plate with addition of a dorsal ulnar pin plate. Prepared specimens were mounted in a custom load frame and loaded in extension with stepwise cyclic load increase. Dorsal plane interfragmentary displacements were compared between the 2 fixation constructs at 50-N and 100-N cyclic load. RESULTS: The addition of the dorsal ulnar pin plate significantly reduced interfragmentary displacements for the dorsal ulnar fragment at the 50 N load application, resulting in mean interfragmentary displacements of -0.1 ± 0.2 mm in comparison to -0.3 ± 0.2 mm with the volar plate-only construct. No other interfragmentary displacement comparisons were significant. No differences were found comparing the one-third and one-half size fragments. CONCLUSIONS: The addition of a dorsal ulnar pin plate improved stability characteristics with respect to the dorsal ulnar fragment. CLINICAL RELEVANCE: The addition of the dorsal ulnar pin plate, although statistically significant, improved displacement by less than 0.3 mm on average and thus may not prove to be important in clinical scenarios.

Treatment of Distal Interphalangeal Ganglion Cysts by Volar Corticosteroid Injection.

BACKGROUND: Various options exist for operative and nonoperative treatment of symptomatic distal interphalangeal (DIP) ganglion cysts. We describe the technique and efficacy of a novel treatment of DIP ganglion cysts using a volar, transtendon, intra-articular injection of corticosteroid. METHODS: This was a single center, retrospective study (2010-2015) of 21 patients who received a volar, intra-articular corticosteroid injection for treatment of DIP ganglion cysts. The patients were contacted via mailing with a short survey. For those potential study participants who did not respond to the mailing or were not seen in follow-up, contact was made via telephone. The primary study outcome was resolution of the cyst; secondary outcomes included pain and postinjection complications. RESULTS: A total of 21 patients (14 female; 7 male) with 23 DIP ganglion cysts were treated in this study. The dominant hand was involved in 56.5% cases. Twelve (52.2%) resolved or had near complete resolution following injection at an average follow-up of 20 months. CONCLUSIONS: For patients with DIP ganglion cysts, this newly described technique of volar, transtendon, intra-articular injection of corticosteroid provides a safe and effective treatment. This technique allows for ease and consistency of needle placement for intra-articular corticosteroid delivery while minimizing the potential soft tissue and infection concerns described with other techniques.

A Novel Technique for the Treatment of Jersey Fingers.

The avulsion of the flexor digitorum profundus from its insertion, or "jersey finger," is a relatively common injury. Numerous modifications have been made to the classification and treatment of this injury since its initial description. We describe a novel variation of the surgical management of jersey finger.

Vascularized Spare Parts Reconstruction of Hand Gunshot Injury.

Reconstruction of extensive traumatic bone and soft tissue deficits in the hand often presents a significant challenge. We present a case of a gunshot wound managed with a resourceful "vascularized spare parts" reconstruction in which a single compromised digit provided two separate vascularized tissue transfers. A rarely reported pedicled phalanx restored osseous stability, a digital fillet flap achieved soft tissue coverage, and the flexor tendons reanimated the hand. An excellent functional and cosmetic result was obtained and the patient was able to return to manual labor within six months of injury.

Surgical Efficiency of Anterior Cruciate Ligament Reconstruction in Outpatient Surgical Center Versus Hospital Operating Room.

Anterior cruciate ligament (ACL) reconstructions are complex orthopedic procedures in which a proficient team is of vital importance. Outpatient surgical centers (OSCs) often provide orthopedic-specific teams; however, hospital operating rooms (ORs) commonly rotate staff. The purpose of this study was to compare the efficiency of pediatric ACL reconstructions between a surgical center and a hospital OR owned and directed by a single institution. Cases examined involved pediatric patients, aged 12 to 18 years (mean age, 15.9±1.5 years), who underwent ACL reconstructions by a single orthopedic surgeon from 2009 to 2014. Procedural efficiency was defined as shorter total OR time, less total staff, and fewer support staff changes. Total OR time was also broken into 3 distinct time periods: in-room to incision time, total procedure time, and stop time to out-of-room time. A total of 49 ACL reconstructions were performed in healthy athletes, with 28 surgeries at the OSC (mean age, 15.7±1.3 years) and 21 surgeries in the hospital OR (mean age, 16.1±1.8 years). Overall efficiency was higher at the OSC, with total OR time improved by 30 minutes on average (P=.0001) with less total staff (P=.0002). Surgical technician and nursing changes occurred 6 and 2.5 times more often in the hospital OR, respectively. Procedural efficiency was greater at the OSC. The provision of consistent and experienced orthopedicspecific teams allows for improvement in OR efficiency, cost, and value. [Orthopedics. 2017; 40(5):297-302.].

Acute and Chronic Low Back Pain.

Low back pain is an extremely common presenting complaint that occurs in upward of 80% of persons. Treatment of an acute episode of back pain includes relative rest, activity modification, nonsteroidal anti-inflammatories, and physical therapy. Patient education is also imperative, as these patients are at risk for further future episodes of back pain. Chronic back pain (>6 months' duration) develops in a small percentage of patients. Clinicians' ability to diagnose the exact pathologic source of these symptoms is severely limited, making a cure unlikely. Treatment of these patients should be supportive, the goal being to improve pain and function.

Acute and chronic low back pain.

Low back pain is an extremely common presenting complaint that occurs in upward of 80% of persons. Treatment of an acute episode of back pain includes relative rest, activity modification, nonsteroidal anti-inflammatories, and physical therapy. Patient education is also imperative, as these patients are at risk for further future episodes of back pain. Chronic back pain (>6 months' duration) develops in a small percentage of patients. Clinicians' ability to diagnose the exact pathologic source of these symptoms is severely limited, making a cure unlikely. Treatment of these patients should be supportive, the goal being to improve pain and function.

Conceptualizing cancer drugs as classifiers.

Cancer and healthy cells have distinct distributions of molecular properties and thus respond differently to drugs. Cancer drugs ideally kill cancer cells while limiting harm to healthy cells. However, the inherent variance among cells in both cancer and healthy cell populations increases the difficulty of selective drug action. Here we formalize a classification framework based on the idea that an ideal cancer drug should maximally discriminate between cancer and healthy cells. More specifically, this discrimination should be performed on the basis of measurable cell markers. We divide the problem into three parts which we explore with examples. First, molecular markers should discriminate cancer cells from healthy cells at the single-cell level. Second, the effects of drugs should be statistically predicted by these molecular markers. Third, drugs should be optimized for classification performance. We find that expression levels of a handful of genes suffice to discriminate well between individual cells in cancer and healthy tissue. We also find that gene expression predicts the efficacy of some cancer drugs, suggesting that these cancer drugs act as suboptimal classifiers using gene profiles. Finally, we formulate a framework that defines an optimal drug, and predicts drug cocktails that may target cancer more accurately than the individual drugs alone. Conceptualizing cancer drugs as solving a discrimination problem in the high-dimensional space of molecular markers promises to inform the design of new cancer drugs and drug cocktails.