Parent-Derived Health State Utilities for Developmental Dysplasia of the Hip.

BACKGROUND: Developmental hip dysplasia (DDH) is a common condition associated with pain, disability and early hip osteoarthritis when untreated. Health utility scores have not previously been defined for a comprehensive set of DDH health states. The purpose of this study was to establish utility scores associated with DDH health states. METHODS: Patients treated for DDH using either Pavlik harness or abduction bracing and closed/open hip reduction between February 2016 and March 2023 were identified. Thirteen vignettes describing health states in the DDH life cycle were developed. Parents of patients were asked to score each state from 0 to 100 using the feeling thermometer. A score of "0" represents the worst state imaginable/death and a score of "100" represents perfect health. Utility scores were calculated and compared between parents of patients treated operatively and nonoperatively. RESULTS: Ninety parents of children with DDH (45 operative, 45 nonoperative) were enrolled. There were 82 (91.1%) female children (median age of 4.9 years at enrollment). Median utility scores ranged from 77.5 [interquartile range (IQR): 70.0 to 90.0] for Pavlik harness and 80.0 (IQR: 60.0 to 86.3) for abduction bracing to 40.0 (IQR: 20.0 to 60.0) for reduction/spica cast and 40.0 (IQR: 20.0 to 50.0) for end-stage hip arthritis. Utility scores were lower in the operative group for Pavlik harness (median 70.0 vs. 80.0, P<0.01), end-stage arthritis (30.0 vs. 40.0, P=0.04), and 1 year after total hip arthroplasty (85.0 vs. 90.0, P=0.03) health states compared with the nonoperative group. There were no differences in other scores. CONCLUSIONS: Thirteen health states related to the life cycle of DDH were collected. Nonoperative interventions for DDH were viewed by parents slightly more favorably than operative treatments or long-term sequelae of untreated DDH. Future studies can assess other potential treatment experiences for patients with DDH or use these scores to perform cost-effectiveness analysis of different screening techniques for DDH. LEVEL OF EVIDENCE: Level III.

Fully automated determination of robotic pedicle screw accuracy and precision utilizing computer vision algorithms.

Historically, pedicle screw accuracy measurements have relied on CT and expert visual assessment of the position of pedicle screws relative to preoperative plans. Proper pedicle screw placement is necessary to avoid complications, cost and morbidity of revision procedures. The aim of this study was to determine accuracy and precision of pedicle screw insertion via a novel computer vision algorithm using preoperative and postoperative computed tomography (CT) scans. Three cadaveric specimens were utilized. Screw placement planning on preoperative CT was performed according to standard clinical practice. Two experienced surgeons performed bilateral T2-L4 instrumentation using robotic-assisted navigation. Postoperative CT scans of the instrumented levels were obtained. Automated segmentation and computer vision techniques were employed to align each preoperative vertebra with its postoperative counterpart and then compare screw positions along all three axes. Registration accuracy was assessed by preoperatively embedding spherical markers (tantalum beads) to measure discrepancies in landmark alignment. Eighty-eight pedicle screws were placed in 3 cadavers' spines. Automated registrations between pre- and postoperative CT achieved sub-voxel accuracy. For the screw tip and tail, the mean three-dimensional errors were 1.67 mm and 1.78 mm, respectively. Mean angular deviation of screw axes from plan was 1.58°. For screw mid-pedicular accuracy, mean absolute error in the medial-lateral and superior-inferior directions were 0.75 mm and 0.60 mm, respectively. This study introduces automated algorithms for determining accuracy and precision of planned pedicle screws. Our accuracy outcomes are comparable or superior to recent robotic-assisted in vivo and cadaver studies. This computerized workflow establishes a standardized protocol for assessing pedicle screw placement accuracy and precision and provides detailed 3D translational and angular accuracy and precision for baseline comparison.

The Longitudinal Effects of Posterior Spinal Fusion with Derotation on Axial Deformity in Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Retrospective case series. OBJECTIVE: To characterize the change in angle of trunk rotation (ATR), axial vertebral rotation (AVR), and body surface rotation (BSR) in patients with adolescent idiopathic scoliosis (AIS) undergoing posterior spinal fusion (PSF) with en-bloc derotation across multiple postoperative visits. SUMMARY OF BACKGROUND DATA: Previous research has documented ATR, AVR, and BSR correction for AIS patients after surgery. However, there is a lack of evidence on the sustainability of this correction over time. METHODS: This was a retrospective study from a single-center prospective surface topographic registry of patients with AIS, age 11-20 at time of surgery, who underwent PSF with en-bloc derotation. Patients with previous spine surgery were excluded. ATR was measured with a scoliometer, AVR through EOS radiographic imaging, and BSR via surface topographic scanning, Data collection occurred at: preoperative, six-week, three-month, six-month, one-year, and two-year postoperative visits. BSR and AVR were tracked at the preoperative apical vertebral level, and the level with maximum deformity, at each respective timepoint. Generalized estimating equations models were used for statistical analysis. Covariates included age, sex, and body mass index. RESULTS: 49 patients (73.4% female, mean age 14.6±2.2 years, mean preoperative coronal curve angle 57.9°±8.5, and 67% major thoracic) were evaluated. ATR correction was significantly improved at all postoperative timepoints and there was no significant loss of correction. AVR Max and AVR Apex were significantly improved at all timepoints but there was a significant loss of correction for AVR Apex between the six-week and one-year visit (P=0.032). BSR Max achieved significant improvement at the three-month visit. BSR Apex was significantly improved at the three-month and one-year visit. CONCLUSION: ATR and AVR demonstrated significant axial plane correction at two-years postoperative in patients undergoing PSF for AIS. BSR did not maintain significant improvement by the two-year visit.

Utilizing robotic-assisted navigation for pelvic instrumentation in pediatric patients with neuromuscular scoliosis: a technical note and case series.

Pelvic fixation is commonly used in correcting pelvic obliquity in pediatric patients with neuromuscular scoliosis and in preserving stability in adult patients with lumbosacral spondylolisthesis or instances of traumatic or osteoporotic fracture. S2-alar-iliac screws are commonly used in this role and have been proposed to reduce implant prominence when compared to traditional pelvic fusion utilizing iliac screws. The aim of this technical note is to describe a technique for robotically navigated placement of S2-alar-iliac screws in pediatric patients with neuromuscular scoliosis, which (a) minimizes the significant exposure needed to identify a bony start point, (b) aids in instrumenting the irregular anatomy often found in patients with neuromuscular scoliosis, and (c) allows for greater precision than traditional open or fluoroscopic techniques. We present five cases that underwent posterior spinal fusion to the pelvis with this technique that demonstrate the safety and efficacy of this procedure.