An Evaluation of the Reliability of Manual Landmark Identification on 3D Segmented Wrists.

BACKGROUND: Three-dimensional (3D) preoperative planning is increasingly used in orthopaedic surgery. Two-dimensional (2D) characterization of distal radial deformities remains inaccurate, and 3D planning requires a reliable reference frame at the wrist. We aim to evaluate the reliability of the determination of anatomical points placed manually on 3D models of the radius to determine which of those points allow reliable morphometric measurements. METHODS: Twenty-three radial scans were reconstructed in 3D. Five operators specialized in the upper limb manually positioned 8 anatomical points on each model. One of the operators repeated the operation 6 times. The anatomical points were based on previously published 3D models used for radial inclination and dorsopalmar tilt measurements. The repeatability and reproducibility of the measurements derived using this manual landmarking were calculated using different measurement methods based on the identified points. An error of ≤2° was considered clinically acceptable. RESULTS: This study of intraobserver and interobserver variability of the anatomic points allowed us to determine the least variable and most accurately defined points. The middle of the ulnar border of the radius, the radial styloid, and the midpoint of the ulnar incisura of the radius were the least variable. The palmar and dorsal ends of the ridge delineating the scaphoid and lunate facets were the most variable. Only 1 of the radial inclination measurement methods was clinically acceptable; the others had a repeatability and reproducibility limit of >2°, making those measurements clinically unacceptable. CONCLUSIONS: The use of isolated points seems insufficient for the development of a wrist reference frame, especially for the purpose of measuring dorsopalmar tilt. If one concurs that an error of 2° is unacceptable for all distal radial measurements, then clinicians should avoid using 3D landmarked points, due to their unreliability, except for radial inclination measured using the radial styloid and the midpoint of the ulnar edge of the radius. A characterization of the wrist using 3D shapes that fit the articular surface of the radius should be considered. LEVEL OF EVIDENCE: Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

An artificial intelligence based on a convolutional neural network allows a precise analysis of the alignment of the lower limb.

PURPOSE: The objective of this study was to develop a numeric tool to automate the analysis of deformity from lower limb telemetry and assess its accuracy. Our hypothesis was that artificial intelligence (AI) algorithm would be able to determine mechanical and anatomical angles to within 1°. METHODS: After institutional review board approval, 1175 anonymized patient telemetries were extracted from a database of more than ten thousand telemetries. From this selection, 31 packs of telemetries were composed and sent to 11 orthopaedic surgeons for analysis. Each surgeon had to identify on the telemetries fourteen landmarks allowing determination of the following four angles: hip-knee-ankle angle (HKA), medial proximal tibial angle (MPTA), lateral distal femoral angle (LDFA), and joint line convergence angle (JLCA). An algorithm based on a machine learning process was trained on our database to automatically determine angles. The reliability of the algorithm was evaluated by calculating the difference of determination precision between the surgeons and the algorithm. RESULTS: The analysis time for obtaining 28 points and 8 angles per image was 48 ± 12 s for the algorithm. The average difference between the angles measured by the surgeons and the algorithm was around 1.9° for all the angles of interest: 1.3° for HKA, 1.6° for MPTA, 2.1° for LDFA, and 2.4° for JLCA. Intraclass correlation was greater than 95% for all angles. CONCLUSION: The algorithm showed high accuracy for automated angle measurement, allowing the estimation of limb frontal alignment to the nearest degree.

Sporadic Schwannomatosis: A Systematic Review Following the 2005 Consensus Statement.

AIMS: To identify the frequency of reports of sporadic schwannomatosis, the types of patients affected, and the nerves affected. PATIENTS AND METHODS: We identified all case reports and case series that reported on patients with sporadic schwannomatosis according to established criteria. RESULTS: The initial search yielded 1,597 studies, of which 15 were included. A total of 38 of 55 individuals met the inclusion criteria. The mean age of the patients was 48 years; 41% were male. Thirty-three patients had peripheral nerve tumors, and 17 had spinal tumors. Twelve had tumors in both locations. Tumor distribution was unilateral in 25 of 30 cases (83.3%) and segmental (limited to one limb or five or fewer contiguous segments of the spine) in 28 of 38 cases (73.7%). CONCLUSION: This systematic review quantified the number of individuals who meet the criteria for sporadic schwannomatosis and better described this population to facilitate the classification of neurofibromatosis in regard to the 2005 consensus statement. Unilateral or segmental distribution of nerve tumors are key aspects when dealing with multiple noncutaneous schwannomas without involvement of the vestibular nerve.

[Sprain of the thumb metacarpal-phalangeal with lesion of the ulnar collateral ligament]. / Entorse de l'articulation métacarpo-phalangienne du pouce avec lésion du ligament collatéral ulnaire.

The sprain of the thumb metacarpal-phalangeal joint must be treated in an adapted way in order to avoid chronic laxity. The comparative and bilateral clinical exam is the main element that will allow to detect laxity. In the case of non laxity, a conservative treatment with a splint makes sense. In the case of laxity with Stener effect, a surgical procedure is recommended in order to reintegrate the collateral ligament. In the case of laxity without Stener effect, the choice of treatment is contentious. A US or MRI would be useful if the Stener effect could be underlying. For whichever treatment opted, rehabilitation is to be started as soon as at week 4, in order to reduce risks of stiffness. The return to any sport or training will depend on the sprain stage and on the possibility to wear a rigid splint or not.

L'entorse de l'articulation métacarpo-phalangienne du pouce doit être traitée de manière adaptée pour éviter une laxité chronique. L'examen clinique bilatéral et comparatif est l'élément central pour dépister une laxité. Il doit être précédé d'une radiographie. En cas d'absence de laxité, un traitement conservateur par attelle se justifie. En cas de laxité avec effet Stener, un traitement chirurgical est indispensable pour réinsérer le ligament collatéral. En cas de laxité sans effet Stener, le traitement est controversé. Un US ou une IRM sont utiles en cas de suspicion d'effet Stener pour statuer sur l'état du ligament. Quel que soit le traitement, la rééducation est débutée dès la 4e semaine pour limiter l'enraidissement. Le retour à la pratique sportive dépend du stade de l'entorse et de la possibilité de porter une attelle rigide.