A Real-Time EMG-Based Fixed-Bandwidth Frequency-Domain Embedded System for Robotic Hand.

The signals from electromyography (EMG) have been used for volitional control of robotic assistive devices with the challenges of performance improvement. Currently, the most common method of EMG signal processing for robot control is RMS (root mean square)-based algorithm, but system performance accuracy can be affected by noise or artifacts. This study hypothesized that the frequency bandwidths of noise and artifacts are beyond the main EMG signal frequency bandwidth, hence the fixed-bandwidth frequency-domain signal processing methods can filter off the noise and artifacts only by processing the main frequency bandwidth of EMG signals for robot control. The purpose of this study was to develop a cost-effective embedded system and short-time Fourier transform (STFT) method for an EMG-controlled robotic hand. Healthy volunteers were recruited in this study to identify the optimal myoelectric signal frequency bandwidth of muscle contractions. The STFT embedded system was developed using the STM32 microcontroller unit (MCU). The performance of the STFT embedded system was compared with RMS embedded system. The results showed that the optimal myoelectric signal frequency band responding to muscle contractions was between 60 and 80 Hz. The STFT embedded system was more stable than the RMS embedded system in detecting muscle contraction. Onsite calibration was required for RMS embedded system. The average accuracy of the STFT embedded system is 91.55%. This study presents a novel approach for developing a cost-effective and less complex embedded myoelectric signal processing system for robot control.

The all-inside all-suture technique demonstrated better biomechanical behaviors in meniscus radial tear repair.

PURPOSE: The purpose of this study was to evaluate the effectiveness of three constructs and techniques for repair of radial tears of the meniscus. METHODS: Thirty fresh frozen porcine menisci were divided equally into three groups consisting of (1) inside-out repair group, (2) a commonly used all-inside suture with anchor hybrid repair construct (AISAH) (Meniscal Cinch™), and (3) an all-inside all-suture repair construct (AIAS) (Knee Scorpion™). Radial tears were created and repaired and then the menisci were secured to the materials testing machine. Both cyclic loading and load-to-failure testing were performed. The displacement, stiffness, response to cyclic loading, and mode of failure were recorded and analyzed statistically. RESULTS: The displacement after cyclic loading (DACL) of the Cinch repair construct group was significantly higher than that of the inside-out repair construct group (p = 0.000) and AIAS repair construct (p = 0.000). There was not a statistical difference of DACL between inside-out and AIAS groups (n.s.). The inside-out construct failed at a significantly higher load than the AISAH repair construct (p = 0.000) and AIAS construct (p = 0.006). The AIAS construct failed at a significantly higher load than the AISAH repair construct (p = 0.009). The AIAS had a higher stiffness than AISAH (p = 0.047). The AIAS had a higher load at 3 mm protrusion than AISAH (p = 0.034). CONCLUSION: The AIAS repair construct had better biomechanical behaviors than AISAH construct and inside-out repair technique. Inside-out sutures and AIAS repair construct had similar biomechanical responses to cyclic loading. The AIAS can be used for meniscus tear surgical repair with less damage to peri-meniscus tissues.

Review article: Patient characteristics that act as risk factors for intraoperative complications in hip, knee, and shoulder arthroplasties.

The number of annual THA's, TKA's, and TSA's is set to increase significantly by the year 2030, making it imperative to understand the risks for negative outcomes in these procedures. While research has studied the patient risk factors for perioperative and postoperative complications, there has been relatively little research for intraoperative complications. After a thorough literature review, the most supported finding was that patients with a BMI >30 had significantly more intraoperative blood loss than those with a BMI <30. All other relationships between patient risk factors and intraoperative complications of interest were inadequately studied.

Review article: Current literature on surgical checklists and handoff tools and application for orthopaedic surgery.

Despite the adaptation of checklists for specific surgeries being developed, there remains a lack of an available standard for an orthopaedic-specific checklist. Benefits of implementing checklists include cost-effectiveness as well as the ability to significantly reduce both mortality and complication rates in a variety of healthcare settings. The aim of this review is to analyze the evidence surrounding the effectiveness of checklists as well as recommend for the development of a standard checklist for specific orthopaedic surgeries such as total joint arthroplasty (TJA).

Bundle Payment for Musculoskeletal Care: Current Evidence (Part 1).

In the face of escalating costs and variations in quality of care, bundled payment models for total joint arthroplasty procedures are becoming increasingly common, both through the Centers for Medicare & Medicaid Services and private payer organizations. The effective implementation of these payment models requires cooperation between multiple service providers to ensure economic viability without deterioration in care quality. This article introduces a stepwise model for the financial analysis of bundled contracts for use in negotiations between hospitals and private payer organizations.

Bundle Payment for Musculoskeletal Care: Current Evidence (Part 2).

In an effort to rein in expenditures and improve quality of care, the Centers for Medicare and Medicaid Services (CMS) has initiated bundled reimbursement programs for total joint arthroplasty (TJA) procedures. The success of CMS's bundled payment models has prompted some private insurers to collaborate with provider organizations to institute similar bundled contracts for TJA. The authors review the experiences of orthopedic groups in the implementation of bundled payments for primary and revision TJA through both public and private payers. The authors also discuss the potential benefits, risks, and barriers groups may encounter under this novel payment model.

Applications of Tissue Engineering in Joint Arthroplasty: Current Concepts Update.

Research in tissue engineering has undoubtedly achieved significant milestones in recent years. Although it is being applied in several disciplines, tissue engineering's application is particularly advanced in orthopedic surgery and in degenerative joint diseases. The literature is full of remarkable findings and trials using tissue engineering in articular cartilage disease. With the vast and expanding knowledge, and with the variety of techniques available at hand, the authors aimed to review the current concepts and advances in the use of cell sources in articular cartilage tissue engineering.

Reimbursement Based on Value in Knee Surgery: What You Need to Know about the Medicare Access and Children's Health Insurance Program Reauthorization Act of 2015.

Health care cost is consuming a large portion of the nation's gross domestic product while placing added economic burdens on physicians and their patients. With total joint replacement being one of the early-targeted procedures in the evolving health care environment, knee surgeons will benefit from developing a critical knowledge on health care reforms and their financial implications. The Medicare Access and Children's Health Insurance Program Reauthorization Act represents a cohesive movement toward value-based payment reform and contains several unchartered rulings that require detailed attention by knee surgeons. In this article, we provide a contextual framework of health care legislation that has led to the formation of the current health policy, and present a comprehensive summary and update on the Merit-Based Incentive Payment Systems and Alternative Payment Models reimbursement models.

Reliability of a New Clinical Instrument for Measuring Internal and External Glenohumeral Rotation.

BACKGROUND: The shoulder plays a critical role in many overhead athletic activities. Several studies have shown alterations in shoulder range of motion (ROM) in the dominant shoulder of overhead athletes and correlation with significantly increased risk of injury to the shoulder and elbow. The purpose of this study was to measure isolated glenohumeral joint internal/external rotation (IR/ER) to determine inter- and intraobserver reliability of a new clinical device. HYPOTHESIS: (1) Inter- and intraobserver reliability would exceed 90% for measures of glenohumeral joint IR, ER, and total arc of motion; (2) the dominant arm would exhibit significantly increased ER, significantly decreased IR, and no difference in total arc of motion compared with the nondominant shoulder; and (3) a significant difference exists in total arc between male and female patients. STUDY DESIGN: Case series. LEVEL OF EVIDENCE: Level 4. METHODS: Thirty-seven subjects (mean age, 23 years; range, 13-54 years) were tested by 2 orthopaedic surgeons. A single test consisted of 1 arc of motion from neutral to external rotation to internal rotation and back to neutral within preset torque limits. Each examiner performed 3 tests on the dominant and nondominant shoulders. Each examiner completed 2 installations. RESULTS: Testing reliability demonstrated that neither trial, installation, nor observer were significant sources of variation. The maximum standard deviation was 1.3° for total arc of motion and less than 2° for most other measurements. Dominant arm ER was significantly greater than nondominant arm ER (P = 0.02), and dominant arm IR was significantly less than nondominant arm IR (P = 0.00). Mean total rotation was 162°, with no significant differences in total rotation between dominant and nondominant arms (P = 0.34). Mean total arc of motion was 45° greater in female subjects. Differences in total arc of motion between male and female subjects was statistically significant (P < 0.00). CONCLUSION: This simple, clinical device allows for both inter- and intraobserver reliability measurements of glenohumeral internal and external rotation.

Baker's Cyst: Diagnostic and Surgical Considerations.

CONTEXT: Popliteal synovial cysts, also known as Baker's cysts, are commonly found in association with intra-articular knee disorders, such as osteoarthritis and meniscus tears. Histologically, the cyst walls resemble synovial tissue with fibrosis evident, and there may be chronic nonspecific inflammation present. Osteocartilaginous loose bodies may also be found within the cyst, even if they are not seen in the knee joint. Baker's cysts can be a source of posterior knee pain that persists despite surgical treatment of the intra-articular lesion, and they are routinely discovered on magnetic resonance imaging scans of the symptomatic knee. Symptoms related to a popliteal cyst origin are infrequent and may be related to size. EVIDENCE ACQUISITION: A PubMed search was conducted with keywords related to the history, diagnosis, and treatment of Baker's cysts-namely, Baker's cyst, popliteal cyst, diagnosis, treatment, formation of popliteal cyst, surgical indications, and complications. Bibliographies from these references were also reviewed to identify related and pertinent literature. STUDY DESIGN: Clinical review. LEVEL OF EVIDENCE: Level 4. RESULTS: Baker's cysts are commonly found associated with intra-articular knee disorders. Proper diagnosis, examination, and treatment are paramount in alleviating the pain and discomfort associated with Baker's cysts. CONCLUSION: A capsular opening to the semimembranosus-medial head gastrocnemius bursa is a commonly found normal anatomic variant. It is thought that this can lead to the formation of a popliteal cyst in the presence of chronic knee effusions as a result of intra-articular pathology. Management of symptomatic popliteal cysts is conservative. The intra-articular pathology should be first addressed by arthroscopy. If surgical excision later becomes necessary, a limited posteromedial approach is often employed. Other treatments, such as arthroscopic debridement and closure of the valvular mechanism, are not well studied and cannot yet be recommended.

Biomechanical evaluation of parasagittal occipital plating: screw load sharing analysis.

STUDY DESIGN: Biomechanical evaluation of occipitocervical instrumentation techniques. OBJECTIVE: Compare methods of occipital instrumentation by quantifying load sharing of occipital screws and measuring motion across instrumented occipitocervical spines. SUMMARY OF BACKGROUND DATA: Newer occipitocervical plate/screw systems that attach to longitudinal rods have been developed to improve fixation. These devices place screws in the center of occipital bone or off-midline. Midline plates offer screw purchase in thicker bone. Off-midline systems may increase the effective moment arm for torsional and lateral bending control. Measurement of screw loads within occipital plates is useful for determining optimal plate configuration. METHODS: Ten cadaveric specimens (occiput-C4) were tested in flexion/extension (FE), lateral bending (LAT), and axial rotation (ROT) over +/-3 Nm pure moment. After intact testing, 4 occipitocervical fixation constructs were tested using washer load cells to assess loading across screws used to fix the plates to the occiput. Parasagittal occipital plates were positioned either convex or concave side facing medially. Each plate was first fixed using 3 screws (rostral, middle, caudal), then with the caudal screw eliminated (simulated failure). Range of motion (ROM) and peak screw loads are reported. RESULTS: ROM decreased from intact to any of the 4 fusion plate configurations in FE, LAT, and ROT (P << 0.05), but not between plate configurations. Screw load significantly decreased from medially convex to medially concave configurations in LAT, but no significant changes were observed in FE or ROT. With caudal screws removed, middle screws peak loads significantly increased in FE and LAT (P < 0.05), but not ROT. CONCLUSION: Occipital screw placement off-midline improves screw loads under lateral bending forces on occipitocervical constructs, though loads for FE and ROT are unchanged. As screws pullout, the loads may be redistributed, resulting in increased screw pullout forces above. Despite the improvement in screw loads for laterally based plates during lateral bending, overall ROM across the occipitocervical junction is unchanged.

Peri-epiphyseal and Overuse Injuries in Adolescent Athletes.

CONTEXT: Overuse injuries of the musculoskeletal system in immature athletes are commonly seen in medical practice. EVIDENCE ACQUISITION: An analysis of published clinical, outcome, and biomechanical studies of adolescent epiphyseal and overuse injuries was performed through 2008 to increase recognition and provide treatment recommendations. RESULTS: Adolescent athletes can sustain physeal and bony stress injuries. Recovery and return to play occur more swiftly if such injuries are diagnosed early and immobilized until the patient is pain-free, typically about 4 weeks for apophyseal and epiphyseal overuse injuries. Certain epiphyseal injuries have prolonged symptoms with delayed treatment, including those involving the bones in the hand, elbow, and foot. If such injuries are missed, prolonged healing and significant restrictions in athletic pursuits may occur. CONCLUSION: Some of these injuries are common to all weightbearing sports and are therefore widely recognized. Several are common in gymnastics but are rarely seen in other athletes. Early recognition and treatment of these conditions lead to quicker recovery and so may prevent season-ending, even career-ending, events from occurring.