STRYDE versus PRECICE magnetic internal lengthening nail for femur lengthening.

INTRODUCTION: Magnetic internal lengthening nails (MILNs) have been used for femoral lengthening to avoid complications associated with external fixation. The titanium version of the MILN (PRECICE®) has been in use since 2011 but had limitations (50-75 lb) in post-operative weight bearing. A new stainless-steel version of the MILN (STRYDE®) allows 150-250 lb of post-operative weight bearing. The aim is to compare the outcomes of using these two different MILNs for both unilateral and bilateral femoral lengthening. METHODS: A single-center, retrospective cohort study was conducted in which patients' records were reviewed from the period from January 2017 to March 2020. A total of 66 femoral lengthening procedures were included in the study and were divided into two groups: STRYDE® group (30 femora) and PRECICE® group (36 femora). Outcomes assessed were the 6-months post-operative Limb Deformity-Scoliosis Research Society (LD-SRS) Score, adjacent joint range of motion (ROM), average distraction rate, bone healing index (BHI), and complications. RESULTS: No statistically significant difference was found between the two groups in regard to the (LD-SRS) score, hip ROM, or knee ROM. Statistically significant differences were found between the two groups in regard to BHI (average of 0.84 months/cm and 0.67 months/cm for STRYDE® and PRECICE®, respectively) and distraction rate (average of 0.6 mm/day and 0.9 mm/day for STRYDE® and PRECICE®, respectively). No mechanical nail complications were reported in the STRYDE® group compared to three events of nail failure in the PRECICE® group. One femur in the PRECICE® group needed BMAC injection for delayed healing compared to four femurs in the STRYDE® group. CONCLUSION: The STRYDE® MILN yields comparable functional results to those of PRECICE® MILN and shows fewer mechanical nail complications. However, STRYDE® MILN requires a slower distraction rate and yields slower healing (larger BHI). LEVEL OF EVIDENCE: Level III, Therapeutic study.

Humerus Lengthening: A Comparison of the Internal Lengthening Nail to External Fixation.

Introduction: Magnetic internal lengthening nails (MILNs) have been used for humeral lengthening to avoid complications associated with external fixation. Purpose/Questions: We compared the 1-year Disabilities of the Arm, Shoulder and Hand (DASH) score, adjacent joint range of motion (ROM), bone healing index (BHI), length achieved, distraction rate, and complications when lengthening the humerus using MILN vs using external fixation. Methods: We conducted a retrospective cohort study of 18 patients (22 humeri) from January 2001 to March 2020 divided into 2 groups, the MILN group (7 patients, 7 humeri) and the mono-lateral fixator group (11 patients, 15 humeri). Results: The MILN group showed larger improvement of DASH scores (average 26.8 and 8 for MILN and fixator groups, respectively), less loss of elbow ROM (average 5° and 7° for MILN and fixator groups, respectively), and shorter time to full recovery of elbow ROM (average 39 days and 122 days for MILN and fixator groups, respectively). In the MILN group, there was slower distraction rate (average 0.66 mm/day and 0.86 mm/day for MILN and fixator groups, respectively), less lengthening achieved (average 5.2 cm and 7 cm for MILN and fixator group, respectively), and a lower lengthening percentage (average 19% and 41% for MILN and fixator group, respectively). Bone healing index (BHI) of 0.94 and 0.99 months/cm for the MILN and the fixator groups were similar. Conclusion: Humeral lengthening using the MILN allowed for early full recovery of joint ROM with comparable functional and radiographic outcomes compared with using external fixators.

Comparison and Validation of Preoperative Planning Techniques for Distal Femoral Osteotomies and Proximal Tibial Osteotomies.

Preoperative planning is important for accurate intraoperative execution in many surgical fields. Planning for distal femoral osteotomies (DFOs) and proximal tibial osteotomies (PTOs) consists of choosing the level of the osteotomy, measuring the angle of the osteotomy based on hip-knee-ankle alignment, and choosing a proper osteotomy wedge size. Medical imaging IT solutions company Sectra has implemented a new osteotomy tool in their radiographic system that is simpler than the accepted standard of modified center of rotation of angulation (mCORA) technique, yet unvalidated. In this study, we aim to compare the Sectra osteotomy tool versus the mCORA technique to measure the osteotomy angles as well as wedge sizes in both DFOs and PTOs to validate this new tool.We enrolled n = 30 consecutive patients with DFOs and n = 30 PTOs from the last year. The Pearson correlation coefficient (PCC) along with descriptive statistics was used to evaluate for similarity between the two techniques. We also compared interobserver and intraobserver reliability using intraclass correlation coefficients (ICC).The PCC for osteotomy angles in DFOs and PTOs were both 0.998 (p < 0.001 for both). For wedge sizes, the PCC in DFOs was 0.993 and 0.980 in PTOs (p < 0.001 for both). ICCs were high for both interobserver measurements in osteotomy angles and wedge sizes (range: 0.989-0.999) as well as intraobserver measurements (0.994-0.999).The Sectra osteotomy tool is a validated tool for preoperative measurements of DFOs and PTOs. It is reliable and simpler than the current practice of the mCORA technique. We suggest future studies to analyze this Sectra osteotomy tool in other settings as to incorporate it into widespread clinical use.

A Staged Approach to Combined Extra-articular Limb Deformity Correction and Total Ankle Arthroplasty for End-Stage Ankle Arthritis.

BACKGROUND: Patients presenting with end-stage ankle osteoarthritis (OA) in the setting of a concomitant extra-articular limb deformity pose a challenging problem that has not yet been described in the literature. We describe a case series of patients treated with external and internal fixation techniques followed by total ankle arthroplasty (TAA) in a staged approach to treat this complex presentation. METHODS: Eight patients with limb deformity and end-stage ankle OA who underwent staged deformity correction and TAA from 2016 to 2019 at our institution were retrospectively identified. Average age was 58.5 (range, 49-68) years, with an average follow-up of 2.6 (range, 0.8-4.2) years. All patients underwent limb reconstruction with either tibial osteotomy with a circular frame (n=6) or intramedullary nail (n=2). Limb deformities consisted of the following: posttraumatic tibial malunion (2), limb length discrepancy (1), acquired tibial deformity (1), genu varum (2), or genu valgum (2). Radiographic parameters were assessed pre- and postoperatively on 51-inch standing and ankle radiographs: limb length discrepancy (LLD), genu varum/valgum deformity, recurvatum deformity, mechanical axis deviation, medial proximal tibial angle, lateral distal tibial angle, anterior distal tibial angle, and tibiotalar alignment. Pre- and postoperative patient-reported outcomes were assessed using 2 metrics, the Limb Deformity-Scoliosis Research Society (LD-SRS) and Patient-Reported Outcomes Measurement Information System (PROMIS) scores (Physical Function, Pain Intensity, Pain Interference, Global Physical Function, and Global Mental Function). RESULTS: Following staged limb deformity correction and TAA, all patients achieved correction of LLD and angular deformities of the lower limb, along with restoration of normal alignment of the ankle joint. There was significant mean improvement in all patient-reported LD-SRS and PROMIS domains, except for LD-SRS mental health. LD-SRS function improved from 2.6 (±0.7) to 4.6 (±0.2), P = .008; pain improved from 2.9 (±0.9) to 4.8 (±0.2), P = .012; self-image improved from 2.9 (±0.4) to 4.7 (±0.3), P < .001; and total LD-SRS improved from 3.3 (±0.4) to 4.8 (±0.2), P = .002. Average satisfaction was 4.9 (±0.3). PROMIS physical function improved from 32.3 (±6.8) to 51.3 (±5.3), P = .008; pain interference improved from 66.0 (±9.1) to 41.3 (±6.2), P = .004; pain intensity improved from 60.0 (±13.3) to 33.1 (±5.3), P = .007; global physical health improved from 39.3 (±6.8) to 60.7 (±5.1), P = .002; global mental health improved from 54.8 (±5.9) to 65.6 (±2.8), P = .007. There was one incidence of pin site infection and one reoperation. CONCLUSION: Deformity correction with either external frame or intramedullary nail fixation followed by TAA in a staged approach was a viable surgical option in the treatment of end-stage ankle OA with concurrent extra-articular limb deformity. This unique approach was capable of achieving deformity correction with improved patient-reported outcomes, minimal complications, and good patient satisfaction. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Patients With Lower Limb Deformity Report Worse Quality of Life Than Control Subjects Regardless of Degree of Deformity.

INTRODUCTION: The purpose of this study was to determine how Limb Deformity Modified Scoliosis Research Society (LD-SRS) scores differ between patients with different types and degrees of limb deformity compared with control subjects. METHODS: Patients who were >17 years and scheduled for reconstructive surgery for limb lengthening or angular deformity with internal and/or external fixation and healthy control subjects were prospectively enrolled. Patients completed the LD-SRS preoperatively. Mechanical axis deviation (MAD) and leg length discrepancy (LLD) were recorded preoperatively. Participants were stratified into five groups based on their diagnosis. ANOVA was used to test for associations between LD-SRS scores and diagnosis as well as mechanical axis deviation. RESULTS: Patients with LLD, angular deformity, or combined LLD and angular deformity reported significantly worse scores than control subjects in LD-SRS Function/Activity, Pain, Self-Image/Appearance, and total score (P < 0.001 for all). Patients with short stature reported significantly worse LD-SRS Self-Image/Appearance (P < 0.001) and total score compared with control subjects (P = 0.015). There was a significant correlation between LLD and LD-SRS Self-Image/Appearance in the LLD and angular deformity group (r = -0.359, P = 0.043). DISCUSSION: Although LD-SRS scores were worse in patients with limb deformity compared to controls, LD-SRS scores were not related to the degree of deformity in most patients, indicating that patient self-perception may be a construct unrelated to objective radiographic or clinical findings.

Spatial Distribution of Collections Yielding Marine Natural Products.

The societal benefits of coral reef ecosystems include shoreline protection, habitat provision for reef fish, tourism, and recreation. Rarely considered in valuation of reefs is the considerable contribution of marine natural products (MNPs) to both human health and the economy. To better understand the relation of MNP discovery with the characteristics and condition of coral reef ecosystems, we initiated a study to track the collection location and taxonomic identity of organisms that have provided pharmacological products. We reviewed collection information and associated data from 298 pharmacological products originating from marine biota during the past 47 years. The products were developed from 232 different marine species representing 15 phyla, and the 1296 collections of these specimens occurred across 69 countries and seven continents. Our evaluation of the collection data was hampered by sundry observational and reporting issues, including imprecise location descriptions and omission of collection dates. Nonetheless, the study provides an important synopsis and appraisal of years of study and exploration by the marine natural product community. Understanding and quantifying the benefits of MNP discovery will depend upon improved reporting of collections, including accurate taxonomic identification, collection dates, and locations.

Controlling for exogenous environmental variables when using data envelopment analysis for regional environmental assessments.

Researchers are increasingly using data envelopment analysis (DEA) to examine the efficiency of environmental policies and resource allocations. An assumption of the basic DEA model is that decisionmakers operate within homogeneous environments. But, this assumption is not valid when environmental performance is influenced by variables beyond managerial control. Understanding the influence of these variables is important to distinguish between characterizing environmental conditions and identifying opportunities to improve environmental performance. While environmental assessments often focus on characterizing conditions, the point of using DEA is to identify opportunities to improve environmental performance and thereby prevent (or rectify) an inefficient allocation of resources. We examine the role of exogenous variables such as climate, hydrology, and topography in producing environmental impacts such as deposition, runoff, invasive species, and forest fragmentation within the United States Mid-Atlantic region. We apply a four-stage procedure to adjust environmental impacts in a DEA model that seeks to minimize environmental impacts while obtaining given levels of socioeconomic outcomes. The approach creates a performance index that bundles multiple indicators while adjusting for variables that are outside management control, offering numerous advantages for environmental assessment.