Jenny L Zheng, Ying Li, Grant Hogue, Megan Johnson, Jason B Anari, Maia D Regan, Keith D Baldwin 

Spine Deform. 2024 Nov 4. doi: 10.1007/s43390-024-00995-9. Online ahead of print.

Abstract

Introduction: Adolescent idiopathic scoliosis (AIS) is a common diagnosis managed by pediatric orthopedic surgeons with nonoperative radiographic monitoring representing a cornerstone of treatment. Differences in practices and techniques for obtaining radiographic studies contribute to variation, cost of care, and hamper data aggregation. We surveyed several large organizations dedicated to children’s orthopedics or scoliosis care to obtain a consensus for radiographic evaluation of AIS.

Methods: A REDCap-based survey was developed across four institutions and beta-tested by staff and fellows from a single institution. The finalized survey was distributed to members of POSNA, PSSG, and SOSORT, and shared on social media. Participants were asked to rank the importance of various datapoints in radiographic assessment of the spinal deformity, skeletal maturity, and study indications during initial, subsequent, preoperative, and final office visits for AIS. Response rate for the overall group was 26%.

Results: Cobb angle was considered the most important (> 94%) radiographic index across all time points. For positioning, 46% of respondents favored arms bent touching clavicles as the ideal positioning for X-rays, and another 24% favored arms down with palms forward (Table 2). The majority of respondents obtain lateral X-rays at the first visit (99%) and at the preoperative visit (70%). At the preoperative visit, sagittal contour (86%), apex location (85%), and Lenke classification (73%) were considered important factors to record. Flexibility studies are primarily obtained at the preoperative visit (89%) and 81% of respondents prefer bending films as the flexibility technique of choice. Regarding measures of skeletal maturity, Sanders bone age was considered to be the most important by over 70% of respondents across initial, subsequent, preoperative and brace wean visits (Fig. 2). MRIs were obtained routinely by 34% of respondents and only when the patient had a concerning symptom or finding for 67% of respondents.

Conclusions: Despite large variations in radiographic examination of AIS, large areas of agreement were found. It is important to establish standards for positioning patients, evaluating skeletal maturity, and obtaining assessments including lateral views, flexibility studies, and advanced imaging. Establishing common practices for radiographic evaluation of AIS will allow for less variation in care and for critical questions to be answered through registry formation and large multicenter data collection.

Significance: This study establishes current practitioner opinion on the radiographic evaluation of the AIS patient. Minimum data sets are useful for data aggregation and answering research questions in the face of data variability.

Level of evidence: Level V.

Keywords: Adolescent idiopathic scoliosis; Imaging; Nonoperative; Radiography; Survey.

https://pubmed.ncbi.nlm.nih.gov/39495401/

Marlene Dufvenberg, Anastasios Charalampidis, Elias Diarbakerli, Birgitta Öberg , Hans Tropp, Anna Aspberg Ahl, Daphne Wezenberg, Henrik Hedevik, Hans Möller, Paul Gerdhem, Allan Abbott

Acta Ortho. 2024 Sep 13:95:536-544.doi: 10.2340/17453674.2024.41911

Abstract

Background and purpose: The study’s purpose was to develop and internally validate a prognostic survival model exploring baseline variables for adolescent idiopathic scoliosis curve progression.

Methods: A longitudinal prognostic cohort analysis was performed on trial data (n = 135) including girls and boys, Cobb angle 25-40°, aged 9-17 years, remaining growth > 1 year, and previously untreated. Prognostic outcome was defined as curve progression of Cobb angle of > 6° prior to skeletal maturity. 34 candidate prognostic variables were tested. Time-to-event was measured with 6-month intervals. Cox proportional hazards regression survival model (CoxPH) was used for model development and validation in comparison with machine learning models (66.6/33.3 train/test data set). The models were adjusted for treatment exposure.

Results: The final primary prognostic model included 127 patients, predicting progress with acceptable discriminative ability (concordance = 0.79, 95% confidence interval [CI] 0.72-0.86). Significant prognostic risk factors were Risser stage of 0 (HR 4.6, CI 2.1-10.1, P < 0.001), larger major curve Cobb angle (HRstandardized 1.5, CI 1.1-2.0, P = 0.005), and higher score on patient-reported pictorial Spinal Appearance Questionnaire (pSAQ) (HRstandardized 1.4, CI 1.0-1.9, P = 0.04). Treatment exposure, entered as a covariate adjustment, contributed significantly to the final model (HR 3.1, CI 1.5-6.0, P = 0.001). Sensitivity analysis displayed that CoxPH maintained acceptable discriminative ability (AUC 0.79, CI 0.65-0.93) in comparison with machine learning algorithms.

Conclusion: The prognostic model (Risser stage, Cobb angle, pSAQ, and menarche) predicted curve progression of > 6° Cobb angle with acceptable discriminative ability. Adding patient report of the pSAQ may be of clinical importance for the prognosis of curve progression.

https://pubmed.ncbi.nlm.nih.gov/39287215/

Christof Birkenmaier, Louise Levrard , Carolin Melcher , Bernd Wegener, Jens Ricke, Boris M Holzapfel, Andrea Baur-Melnyk , Dirk Mehrens 

Skeletal Radiol. 2024 Aug;53(8):1517-1528.doi: 10.1007/s00256-024-04592-9. Epub 2024 Feb 21.

Abstract

Objective: Distances and angles measured from long-leg radiographs (LLR) are important for surgical decision-making. However, projectional radiography suffers from distortion, potentially generating differences between measurement and true anatomical dimension. These phenomena are not uniform between conventional radiography (CR) digital radiography (DR) and fan-beam technology (EOS). We aimed to identify differences between these modalities in an experimental setup.

Materials and methods: A hemiskeleton was stabilized using an external fixator in neutral, valgus and varus knee alignment. Ten images were acquired for each alignment and each modality: one CR setup, two different DR systems, and an EOS. A total of 1680 measurements were acquired and analyzed.

Results: We observed great differences for dimensions and angles between the 4 modalities. Femoral head diameter measurements varied in the range of > 5 mm depending on the modality, with EOS being the closest to the true anatomical dimension. With functional leg length, a difference of 8.7% was observed between CR and EOS and with the EOS system being precise in the vertical dimension on physical-technical grounds, this demonstrates significant projectional magnification with CR-LLR. The horizontal distance between the medial malleoli varied by 20 mm between CR and DR, equating to 21% of the mean.

Conclusions: Projectional distortion resulting in variations approaching 21% of the mean indicate, that our confidence on measurements from standing LLR may not be justified. It appears likely that among the tested equipment, EOS-generated images are closest to the true anatomical situation most of the time.

Keywords: Cone-beam; Conventional radiography; Digital radiography; Distortion; EOS; Fan-beam; Lower extremity; Projectional distortion; Slot-scanner; Valgus; Varus.

https://pubmed.ncbi.nlm.nih.gov/38378861/

Frances K W Wan, Alex T H Mak, Claire W Y Chung, Joanne Y

EEE Trans Neural Syst Rehabil Eng. 2024:32:2106-2113. doi: 10.1109/TNSRE.2024.3398029 Epub 2024 Jun 7

Abstract

Forward sagittal alignment affects physical performance, is associated with pain and impacts the health-related quality of life of the elderly. Interventions that help seniors to improve sagittal balance are needed to inhibit the progression of pain and disability.

A motion-sensing video game (active game) is developed in this study to monitor sitting and standing postures in real-time and facilitate the postural learning process by using optical sensors to measure body movement and a video game to provide visual feedback.
Ten female subjects (mean age: 60.0 ± 5.2 years old; mean BMI: 21.4 ± 1.9) with adult degenerative scoliosis (mean major Cobb’s angle: 38.1° ± 22.7°) participate in a 6-week postural training programme with three one-hour postural training sessions a week.
Eleven body alignment measurements of their perceived “ideal” sitting and standing postures are obtained before and after each training session to evaluate the effectiveness of postural learning with the game.
The participants learn to sit and stand with increased sagittal alignment with a raised chest and more retracted head position. The forward shift of their head and upper body is significantly reduced after each training session.
Although this immediate effect only partially sustained after the 6-week program, the participants learned to adjust their shoulder and pelvis level for a better lateral alignment in standing.
The proposed postural training system, which is presented as a gameplay with real-time visual feedback, can effectively help players to improve their postures.
This pilot feasibility study explores the development and initial assessment of a motion-based video game designed for postural training in older adults with adult degenerative scoliosis, and demonstrates the usability and benefits of active gameplay in motor training.

https://pubmed.ncbi.nlm.nih.gov/38717877/

Jasper W van der Graaf, Miranda L van Hooff, Bram van Ginneken, Merel Huisman, Matthieu Rutten, Dominique Lamers, Nikolas Lessmann, Marinus de Kleuver 
Eur Radiol 2024 Feb 21.doi: 10.1007/s00330-024-10616-8

Abstract

Objectives: Severity of degenerative scoliosis (DS) is assessed by measuring the Cobb angle on anteroposterior radiographs. However, MRI images are often available to study the degenerative spine. This retrospective study aims to develop and evaluate the reliability of a novel automatic method that measures coronal Cobb angles on lumbar MRI in DS patients.

Materials and methods: Vertebrae and intervertebral discs were automatically segmented using a 3D AI algorithm, trained on 447 lumbar MRI series. The segmentations were used to calculate all possible angles between the vertebral endplates, with the largest being the Cobb angle. The results were validated with 50 high-resolution sagittal lumbar MRI scans of DS patients, in which three experienced readers measured the Cobb angle. Reliability was determined using the intraclass correlation coefficient (ICC).

Results: The ICCs between the readers ranged from 0.90 (95% CI 0.83-0.94) to 0.93 (95% CI 0.88-0.96). The ICC between the maximum angle found by the algorithm and the average manually measured Cobb angles was 0.83 (95% CI 0.71-0.90). In 9 out of the 50 cases (18%), all readers agreed on both vertebral levels for Cobb angle measurement. When using the algorithm to extract the angles at the vertebral levels chosen by the readers, the ICCs ranged from 0.92 (95% CI 0.87-0.96) to 0.97 (95% CI 0.94-0.98).

Conclusion: The Cobb angle can be accurately measured on MRI using the newly developed algorithm in patients with DS. The readers failed to consistently choose the same vertebral level for Cobb angle measurement, whereas the automatic approach ensures the maximum angle is consistently measured.

Clinical relevance statement: Our AI-based algorithm offers reliable Cobb angle measurement on routine MRI for degenerative scoliosis patients, potentially reducing the reliance on conventional radiographs, ensuring consistent assessments, and therefore improving patient care.

Key points: • While often available, MRI images are rarely utilized to determine the severity of degenerative scoliosis. • The presented MRI Cobb angle algorithm is more reliable than humans in patients with degenerative scoliosis. • Radiographic imaging for Cobb angle measurements is mitigated when lumbar MRI images are available.

Keywords: Cobb angle; Deep learning; Magnetic resonance imaging; Scoliosis; Spine.

https://pubmed.ncbi.nlm.nih.gov/38383922/