Evaluating the Readability of Patient Education Materials for Anterior Vertebral Body Tethering, Distraction-Based Methods, and Posterior Spinal Fusion for the Treatment of Pediatric Spinal Deformity.

BACKGROUND: The Internet is an important source of information for patients, but its effectiveness relies on the readability of its content. Patient education materials (PEMs) should be written at or below a sixth-grade reading level as outlined by agencies such as the American Medical Association. This study assessed PEMs' readability for the novel anterior vertebral body tethering (AVBT), distraction-based methods, and posterior spinal fusion (PSF) in treating pediatric spinal deformity. METHODS: An online search identified PEMs using the terms "anterior vertebral body tethering," "growing rods scoliosis," and "posterior spinal fusion pediatric scoliosis." We selected the first 20 general medical websites (GMWs) and 10 academic health institution websites (AHIWs) discussing each treatment (90 websites total). Readability tests for each webpage were conducted using Readability Studio software. Reading grade levels (RGLs), which correspond to the US grade at which one is expected to comprehend the text, were calculated for sources and independent t tests compared with RGLs between treatment types. RESULTS: The mean RGL was 12.1 ± 2.0. No articles were below a sixth-grade reading level, with only 2.2% at the sixth-grade reading level. AVBT articles had a higher RGL than distraction-based methods (12.7 ± 1.6 vs 11.9 ± 1.9, P = 0.082) and PSF (12.7 ± 1.6 vs 11.6 ± 2.3, P = 0.032). Materials for distraction-based methods and PSF were comparable (11.9 ± 1.9 vs 11.6 ± 2.3, P = 0.566). Among GMWs, AVBT materials had a higher RGL than distraction-based methods (12.9 ± 1.4 vs 12.1 ± 1.8, P = 0.133) and PSF (12.9 ± 1.4 vs 11.4 ± 2.4, P = 0.016). CLINICAL RELEVANCE: Patients' health literacy is important for shared decision-making. Assessing the readability of scoliosis treatment PEMs guides physicians when sharing resources and discussing treatment with patients. CONCLUSION: Both GMWs and AHIWs exceed recommended RGLs, which may limit patient and parent understanding. Within GMWs, AVBT materials are written at a higher RGL than other treatments, which may hinder informed decision-making and patient outcomes. Efforts should be made to create online resources at the appropriate RGL. At the very least, patients and parents may be directed toward AHIWs; RGLs are more consistent.

Femur Strength is Similar Before and After Iatrogenic Fracture During Total Hip Arthroplasty: A Biomechanical Analysis.

Background: The purpose of this study was to compare the biomechanical strength of femurs before an iatrogenic periprosthetic fracture vs after an initial fracture with supporting cerclage fixation during cementless total hip arthroplasty. Material and methods: Nineteen composite femurs and 5 matched pairs of cadaveric femurs were implanted with a single-wedge or dual-wedge tapered femoral stem and tested for ultimate load to failure producing a periprosthetic fracture. Following initial fracture, each femur was cerclaged with Vitallium cables and retested for ultimate load to failure. The mean force eliciting iatrogenic fracture before cabling and that after cabling were compared with a two-sided paired Student's t-test. Results: All composite femurs developed periprosthetic fractures with an average length extension from the calcar of 75.17 mm. For the 19 composite femurs, the mean ultimate load to failure before cabling and that after cabling were not significantly different (2422.95 N vs 2505.14 N, P = .678). For the 10 cadaveric femurs, the mean ultimate load to failure for the initial fracture vs that after cabling was statistically comparable (5828.62 N vs 7002.63 N, P = .126). Subanalysis of the 5 cadaveric femurs with a double-wedge stem revealed a significantly higher mean load to failure following cabling (5007.38 N vs 7811.17 N, P = .011). Conclusion: Biomechanical strength was similar for femurs that sustained an initial iatrogenic periprosthetic fracture and the same femurs cabled with cerclage wires after being fractured. These data may assist in operative decision-making for treating iatrogenic fractures during total hip arthroplasty.

Addition of the Sartorius Tendon Improves Biomechanics of a Four-Strand Hamstring Anterior Cruciate Ligament Autograft.

PURPOSE: The purpose of this study was to quantify and compare the biomechanical properties and change in graft size when adding the sartorius tendon as a fifth strand to a four-strand ST-G hamstring autograft. Additionally, the sartorius tendon was tested individually to quantify its independent biomechanical properties. METHODS: Four-strand and five-strand hamstring tendon grafts were harvested from matched cadaveric knees (mean age: 81.6 ± 9.8). These matched grafts were biomechanically tested using a MTS servohydraulic test system at a rate of testing representative of physiologic tears. The mean diameter, cross-sectional area, and ultimate load to failure were quantified and compared with a one-sided, paired Student's t-test. A P < .05 was considered statistically significant. RESULTS: The mean diameter of the five-strand graft was significantly larger than the four-strand graft (9.30 ± .84 mm vs 8.10 ± .42 mm; P = .002). The average ultimate load to failure of the five-strand graft was 65.3% higher than the four-strand graft (2984.05 ± 1085.11 N vs. 1805.03 ± 557.69 N; P = .009) and added 14.8% to the diameter of the four strand ST-G autograft. CONCLUSIONS: The addition of the sartorius tendon to a four-strand hamstring autograft significantly increased ultimate load to failure by 65%, graft cross-sectional area by 32%, and graft diameter by 15% compared to a traditional four-strand ST-G autograft. This information can be helpful to surgeons who wish to improve the strength of a four-strand ST-G autograft and for undersized grafts as an alternative to allograft supplementation. CLINICAL RELEVANCE: The addition of the sartorius to the four-strand ST-G hamstring autograft significantly increases the ultimate load to failure and overall graft diameter, which can be particularly helpful in undersized autografts as an alternative to allograft supplementation.

Variability of Cutting and Thermal Dynamics Between New and Used Acetabular Reamers During Total Hip Arthroplasty.

BACKGROUND: Aseptic loosening of the acetabular component remains one of the leading causes of early failure of total hip arthroplasty. Poor apposition of bone onto the implant surface can be due to inaccurate reaming and osteonecrosis of the acetabular bone due to the heat generated while reaming. METHODS: New and used acetabular reamers were tested on an MTS system using a clinically relevant force of 87.6 N. A thermal profile and depth achieved by the reamers were analyzed and compared between the 2 cohorts. Heat generated and force required for the community used reamers to achieve the same depth as the new reamers were subsequently analyzed. RESULTS: The new reamers achieved a depth 3.4 mm deeper than the community reamers (P < .001). The new reamers generated 4.1°C less heat than the community reamers (P = .007) under the same force and time. When programmed to ream to the average depth of the new reamers, the community reamers generated 16.8°C more heat (P = .002) and required forces 95-318% greater than the 87.6 N force used by the new reamers. CONCLUSIONS: Community use of reamers will cause variations in depth of penetration and increased temperatures at a clinically generated force vs new reamers. When community reamers were forced to the same depths the new reamers achieved, a significantly greater amount of heat was generated, and an increased amount of time was needed, both of which are known risk factors for osteonecrosis.