Conservative treatment of congenital radial head subluxation and non-traumatic elbow locking: A case report.

Congenital radial head subluxation is relatively rare and may be overlooked due to mild symptoms. The diagnosis mainly relies on imaging and history. Observation is an option for those with insignificant symptoms, while surgical intervention, such as ulnar osteotomy or arthroscopy, is often required when dysfunction exists. A 30-year-old man was admitted with congenital radial head dislocation, which was treated with manipulative repositioning. During follow-up, the patient regained the original mobility of the elbow joint and had no recurrence of dislocation. In conclusion, in adults with congenital dislocation of the radial head, we recommend conservative treatment as a first step.

Use of F18 bioglass putty for induced membrane technique in segmental bone defect of the radius in rabbits.

PURPOSE: To evaluate the inductive capacity of F18 bioglass putty on the induced membrane technique in a segmental bone defect of the rabbit's radius. METHODS: Ten female Norfolk at 24 months of age were used. The animals were randomly separated based on postoperative time points: five rabbits at 21 and four at 42 days. A 1-cm segmental bone defect was created in both radii. The bone defects were filled with an F18 bioglass putty. RESULTS: Immediate postoperative radiographic examination revealed the biomaterial occupying the segmental bone defect as a well-defined radiopaque structure with a density close to bone tissue. At 21 and 42 days after surgery, a reduction in radiopacity and volume of the biomaterial was observed, with particle dispersion in the bone defect region. Histologically, the induced membrane was verified in all animals, predominantly composed of fibrocollagenous tissue. In addition, chondroid and osteoid matrices undergoing regeneration, a densely vascularized tissue, and a foreign body type reaction composed of macrophages and multinucleated giant cells were seen. CONCLUSIONS: the F18 bioglass putty caused a foreign body-type inflammatory response with the development of an induced membrane without expansion capacity to perform the second stage of the Masquelet technique.

Osteoid osteoma of the distal radius presenting as an inconspicuous swelling in a young child.

Osteoid osteoma is a benign osteoblastic tumour with a predilection for the lower extremity that rarely affects the forearm. It is commonly seen in adolescents and young adults, and is seldom diagnosed in the paediatric age group. We report a boy in his early childhood who presented with a swelling over the distal forearm, which was incidentally noted by the mother 3 months ago. Plain radiographs showed diffuse sclerosis of the dorsal cortex of the distal radius. CT scan showed a central lucent nidus in the intramedullary region and surrounding sclerosis in the radial metaphysis, confirming the diagnosis of osteoid osteoma. The patient was successfully treated by surgical en bloc resection of the nidus and was asymptomatic at 1-year follow-up. Non-specific symptoms at presentation make it a challenge to diagnose osteoid osteoma in children and it needs to be considered in the differential diagnosis when radiographs show lytic lesions in the bone.

Digital smart internal fixation surgery for coronal process basal fracture with normal joint spaces or radius-shortening: Occult factor of radius-ulna load sharing.

BACKGROUND: Reasonable postoperative humeroradial and humeroulnar joint spaces maybe an important indicator in biomechanical stability of smart internal fixation surgery for coronoid process basal fractures (CPBF). The aim of this study is to compare elbow articular stresses and elbow-forearm stability under smart internal fixations for the CPBF between normal elbow joint spaces and radius-shortening, and to determine the occult factor of radius-ulna load sharing. METHODS: CT images of 70 volunteers with intact elbow joints were retrospectively collected for accurate three-dimensional reconstruction to measure the longitudinal and transverse joint spaces. Two groups of ten finite element (FE) models were established prospectively between normal joint space and radius-shortening with 2.0 mm, including intact elbow joint and forearm, elbow-forearm with CPBF trauma, anterior or posterior double screws-cancellous bone fixation, mini-plate-cancellous bone fixation. Three sets of physiological loads (compression, valgus, varus) were used for FE intelligent calculation, FE model verification, and biomechanical and motion analysis. RESULTS: The stress distribution between coronoid process and radial head, compression displacements and valgus angles of elbow-forearm in the three smart fixation models of the normal joint spaces were close to those of corresponding intact elbow model, but were significantly different from those of preoperative CPBF models and fixed radius-shortening models. The maximum stresses of three smart fixation instrument models of normal joint spaces were significantly smaller than those of the corresponding fixed radius-shortening models. CONCLUSIONS: On the basis of the existing trauma of the elbow-forearm system in clinical practice, which is a dominant factor affecting radius-ulna load sharing, the elbow joint longitudinal space has been found to be the occult factor affecting radius-ulna load sharing. The stability and load sharing of radius and ulna after three kinds of smart fixations of the CPBF is not only related to the anatomical and biomechanical stability principles of smart internal fixations, but also closely related to postoperative elbow joint longitudinal space.

Bone microarchitecture and strength assessment in adults with osteogenesis imperfecta using HR-pQCT: normative comparison and challenges.

Data on bone microarchitecture in osteogenesis imperfecta (OI) are scarce. The aim of this cross-sectional study was to assess bone microarchitecture and strength in a large cohort of adults with OI using high-resolution peripheral quantitative computed tomography (HR-pQCT) and to evaluate challenges of using HR-pQCT in this cohort. Second-generation HR-pQCT scans were obtained at the distal radius and tibia in 118 men and women with Sillence OI type I, III, or IV using an extremity-length-dependent scan protocol. In total, 102 radius and 105 tibia scans of sufficient quality could be obtained, of which 11 radius scans (11%) and 14 tibia scans (13%) had a deviated axial scan angle as compared with axial angle data of 13 young women. In the scans without a deviated axial angle and compared with normative HR-pQCT data, Z-scores at the radius for trabecular bone mineral density (BMD), number, and separation were -1.6 ± 1.3, -2.5 ± 1.4, and -2.7 (IQR: 2.7), respectively. They were -1.4 ± 1.5 and -1.1 ± 1.2 for stiffness and failure load and between ±1 for trabecular thickness and cortical bone parameters. Z-scores were significantly lower for total and trabecular BMD, stiffness, failure load, and cortical area and thickness at the tibia. Additionally, local microarchitectural inhomogeneities were observed, most pronounced being trabecular void volumes. In the scans with a deviated axial angle, the proportion of Z-scores <-4 or >4 was significantly higher for trabecular BMD and separation (radius) or most total and trabecular bone parameters (tibia). To conclude, especially trabecular bone microarchitecture and bone strength were impaired in adults with OI. HR-pQCT may be used without challenges in most adults with OI, but approximately 12% of the scans may have a deviated axial angle in OI due to bone deformities or scan positioning limitations. Furthermore, standard HR-pQCT parameters may not always be reliable due to microarchitectural inhomogeneities nor fully reflect all inhomogeneities.

OI is a rare condition with large clinical heterogeneity. One of the major characteristics associated with OI is the increased fracture risk due to defects in bone structure and material. Data on the defects in bone structure at the micrometer level (i.e. bone microarchitecture) are scarce. Bone microarchitecture can be assessed noninvasively using HR-pQCT, but its use in OI has not extensively been described. Yet, potential challenges may arise related to among others the occurrence of short extremities and skeletal deformities in OI. We assessed bone microarchitecture and strength in 118 adults with OI types I, III, or IV using HR-pQCT with an extremity-length-dependent scan protocol. Additionally, we evaluated potential challenges of using HR-pQCT in this cohort. Our results demonstrated that predominantly trabecular microarchitecture­especially trabecular number and separation­and overall bone strength were impaired in adults with OI as compared with normative data. Furthermore, we observed various microarchitectural inhomogeneities, most pronounced being trabecular void volumes. Regarding applicability, HR-pQCT could be used without challenges in most adults with OI. However, deviations in scan region may potentially influence HR-pQCT parameters, and standard HR-pQCT analyses may not always give accurate results due to microarchitectural inhomogeneities nor fully reflect all microarchitectural inhomogeneities.

In vivo research on 3D-printed composite PLGA and PDLLA-HA absorbable scaffolds for repairing radius defects in rabbits.

OBJECTIVES: Despite being an important research topic in oral biomaterials, few studies have demonstrated the differences between poly(d,l-lactide-co-glycolide)/hydroxyapatite (PLGA/HA) and poly(d,l-lactic acid)/hydroxyapatite (PDLLA/HA). In this study, PLGA/HA and PDLLA/HA scaffolds were prepared using three-dimensional (3D) printing technology and implanted into radius defects in rabbits to assess their effects on bone regeneration. METHODS: In this study, 6 mm × 4 mm bone defects were generated in the bilateral radii of rabbits. 3D-printed PLGA/HA and PDLLA/HA scaffolds were implanted into the defects. X-ray imaging, micro-computed tomography, and hematoxylin-eosin staining were performed to observe the degradation of the materials, the presence of new bone, and bone remodeling in the bone defect area. RESULTS: The PLGA/HA scaffolds displayed complete degradation at 20 weeks, whereas PDLLA/HA scaffolds exhibited incomplete degradation. Active osteoblasts were detected in both groups. The formation of new bone, bone marrow cavity reconstruction, and cortical bone remodeling were better in the PLGA/HA group than in the PDLLA/HA group. CONCLUSIONS: PLGA/HA scaffolds performed better than PDLLA/HA scaffolds in repairing bone defects, making the former scaffolds more suitable as bone substitutes at the same high molecular weight.

Measurement of Radiological Parameters of Distal Radius Fracture Using the Ulnar Axis Compared with the Radial Axis.

Background: The long axis of the radius is a standard reference for measuring radiological parameters in distal radius fractures. However, in patients with severe comminution and anatomical variation with distal radius bowing, it is challenging to assess using the long axis of the radius. The long axis of the ulna can be used as an alternative reference. The aim of this study is to assess the reliability and level of agreement using the long axis of the ulna as an alternative reference in comparison to the long axis of the radius. Methods: Posteroanterior (PA) radiography of the wrist in patients with acute distal radius fractures was evaluated in two rounds by four observers. Radial height, radial inclination and ulnar variance were measured using radial and ulnar long axis as references. The intraobserver and interobserver reliability of the measurements with two reference axes was assessed using intraclass correlation coefficient (ICC). The level of agreement was determined using the Bland-Altman plot. Results: In total, 59 patients who underwent PA radiography of the wrist were included in this study. All parameters exhibited good agreement between the two methods, with a mean difference of nearly zero (radial height = -0.03 mm, radial inclination = -0.14° and ulnar variance = 0.03 mm). The limits of agreement in radial height (-2.87, 2.82 mm) and ulnar variance (-0.81, 0.87 mm) were narrow. However, for the radial inclination, it was wider (-6.21, 5.94°). Intraobserver reliability between the long axis of radius and ulna (ICC = 0.85-0.99 and 0.84-0.98, respectively) was good to excellent. The interobserver reliability of each parameter was excellent (ICC = 0.94-0.97). Conclusions: The ulnar long axis can be used as an alternative reference for measuring radial height, radial inclination and ulnar variance in PA radiography of the wrist in acute distal radius fracture, particularly if the radial long axis is distorted. Level of Evidence: Level III (Diagnostic).

Fracture risk based on high-resolution peripheral quantitative computed tomography measures does not vary with age in older adults-the bone microarchitecture international consortium prospective cohort study.

Fracture risk increases with lower areal bone mineral density (aBMD); however, aBMD-related estimate of risk may decrease with age. This may depend on technical limitations of 2-dimensional (2D) dual energy X-ray absorptiometry (DXA) which are reduced with 3D high-resolution peripheral quantitative computed tomography (HR-pQCT). Our aim was to examine whether the predictive utility of HR-pQCT measures with fracture varies with age. We analyzed associations of HR-pQCT measures at the distal radius and distal tibia with two outcomes: incident fractures and major osteoporotic fractures. We censored follow-up time at first fracture, death, last contact or 8 years after baseline. We estimated hazard ratios (HR) and 95%CI for the association between bone traits and fracture incidence across age quintiles. Among 6835 men and women (ages 40-96) with at least one valid baseline HR-pQCT scan who were followed prospectively for a median of 48.3 months, 681 sustained fractures. After adjustment for confounders, bone parameters at both the radius and tibia were associated with higher fracture risk. The estimated HRs for fracture did not vary significantly across age quintiles for any HR-pQCT parameter measured at either the radius or tibia. In this large cohort, the homogeneity of the associations between the HR-pQCT measures and fracture risk across age groups persisted for all fractures and for major osteoporotic fractures. The patterns were similar regardless of the HR-pQCT measure, the type of fracture, or the statistical models. The stability of the associations between HR-pQCT measures and fracture over a broad age range shows that bone deficits or low volumetric density remain major determinants of fracture risk regardless of age group. The lower risk for fractures across measures of aBMD in older adults in other studies may be related to factors which interfere with DXA but not with HR-pQCT measures.

Prunes preserve cortical density and estimated strength of the tibia in a 12-month randomized controlled trial in postmenopausal women: The Prune Study.

Non-pharmacological therapies, such as whole-food interventions, are gaining interest as potential approaches to prevent and/or treat low bone mineral density (BMD) in postmenopausal women. Previously, prune consumption preserved two-dimensional BMD at the total hip. Here we demonstrate that prune consumption preserved three-dimensional BMD and estimated strength at the tibia. PURPOSE: Dietary consumption of prunes has favorable impacts on areal bone mineral density (aBMD); however, more research is necessary to understand the influence on volumetric BMD (vBMD), bone geometry, and estimated bone strength. METHODS: This investigation was a single center, parallel arm 12-month randomized controlled trial (RCT; NCT02822378) to evaluate the effects of 50 g and 100 g of prunes vs. a Control group on vBMD, bone geometry, and estimated strength of the radius and tibia via peripheral quantitative computed tomography (pQCT) in postmenopausal women. Women (age 62.1 ± 5.0yrs) were randomized into Control (n = 78), 50 g Prune (n = 79), or 100 g Prune (n = 78) groups. General linear mixed effects (LME) modeling was used to assess changes over time and percent change from baseline was compared between groups. RESULTS: The most notable effects were observed at the 14% diaphyseal tibia in the Pooled (50 g + 100 g) Prune group, in which group × time interactions were observed for cortical vBMD (p = 0.012) and estimated bone strength (SSI; p = 0.024); all of which decreased in the Control vs. no change in the Pooled Prune group from baseline to 12 months/post. CONCLUSION: Prune consumption for 12 months preserved cortical bone structure and estimated bone strength at the weight-bearing tibia in postmenopausal women.

Does simultaneous comminuted fracture of both radial ends represent a distinct fracture pattern?

BACKGROUND: Although isolated distal radius and radial head fractures are common injuries, simultaneous ipsilateral fractures are uncommon. They can range from simple undisplaced fractures at either end to severely comminuted ipsilateral proximal and distal radial fractures. Few cases have been reported with concomitant comminuted distal radius and radial head fractures, and no treatment guidelines are available. Decisions are often based on personal recommendations. The purpose of our study is to increase awareness of this injury pattern and to discuss the mechanism of injury, treatment approach, and functional outcome. METHODS: Skeletally mature patients with comminuted simultaneous ipsilateral fractures of the distal and proximal radius from 2016 to 2021 were identified and studied retrospectively. Demographic information, mechanism of injury, treatment approach, and complication rate were analyzed. Radiographic assessment for inadequacy or loss of reduction and radiographic parameters of the distal radius, including radial inclination, radial length, and palmar inclination, was performed immediately postoperatively and at the final follow-up. Clinical outcomes were determined by calculating the Visual Analog Scale (VAS) score, measuring the range of motion in both joints, and using the Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) score at the final follow-up. RESULTS: A total of 11 patients met the inclusion criteria. All had ipsilateral Mason III radial head fractures and type C (according to the Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification) intra-articular distal radius fracture. On-table radial head reconstruction and fixation with a proximal radius plate were used for radial head fractures, and osteosynthesis with an anatomic volar locking plate was used for distal radius fractures. The mean follow-up duration was 32 months (range 12-65 months). At the final follow-up, osseous union of both the radial head and distal radius was observed in all patients. The mean VAS score was 1.5 (range 0-7) at rest and 3.9 (range 0-9) with activities, while the mean QuickDASH score was 32 (range 12-65). No significant complications were recorded. CONCLUSION: Simultaneous comminuted fractures of the ipsilateral distal radius and radial head represent a distinct injury pattern, most likely resulting from high-energy trauma, such as falling from a height onto an outstretched hand. Greater emphasis should be placed on clinical examination and radiological imaging of the elbow in cases of wrist injuries and vice versa. Treatment involving on-table reconstruction of the radial head and open reduction and internal fixation with a volar plate can lead to good radiological and functional outcomes.

Radial nerve palsy in the newborn combined with congenital radial head dislocation: Case report and literature review.

RATIONALE: Radial nerve palsy in the newborn and congenital radial head dislocation (CRHD) are both rare disorders, and early diagnosis is challenging. We reported a case of an infant with concurrent presence of these 2 diseases and provide a comprehensive review of the relevant literature. The purpose of the study is to share diagnostic and treatment experiences and provide potentially valuable insights. PATIENT CONCERNS: A newborn has both radial nerve palsy and CRHD, characterized by limited wrist and fingers extension but normal flexion, normal shoulder and elbow movement on the affected side, characteristic skin lesions around the elbow, and an "audible click" at the radial head. The patient achieved significant improvement solely through physical therapy and observation. DIAGNOSES: The patient was diagnosed with radial nerve palsy in the newborn combined with CRHD. INTERVENTIONS: The patient received regular physical therapy including joint function training, low-frequency pulse electrical therapy, acupuncture, paraffin treatment, as well as overnight splint immobilization. OUTCOMES: The child could actively extend the wrist to a neutral position and extend all fingers. LESSONS: If a neonate exhibits limited extension in the wrist and fingers, but normal flexion, along with normal shoulder and elbow movement, and is accompanied by skin lesions around the elbow, there should be a high suspicion of radial nerve palsy in the newborn.

Is There a Correlation between the Radiological and Clinical Outcome after Core Decompression of the Radius for Kienböck Disease?

Background: Despite the good clinical results in the treatment of Kienböck disease with distal radius core decompression, a radiological progression to a certain degree in the long-term follow-up is possible. Is there a negative correlation between the clinical improvement of the patients and the radiological progression? Methods: We retrospectively reviewed the radiological and clinical results of 24 patients (mean age: 38 years; 10 women) treated with core decompression for Kienböck disease. The mean follow-up was 10 years. Results: A radiologic progression in the Lichtman classification was seen in nine patients. The Spearman correlation did not show any correlation between this radiological progression and the clinical outcome. Namely -0.06 between Mayo and Lichtman classification and 0.16 between VAS and Lichtman classification. Conclusions: We found that the clinical outcomes do not deteriorate despite a radiological progression of patients treated with core decompression for Kienböck disease Level of Evidence: Level IV (Therapeutic).

Automatic Segmentation and Radiologic Measurement of Distal Radius Fractures Using Deep Learning.

Background: Recently, deep learning techniques have been used in medical imaging studies. We present an algorithm that measures radiologic parameters of distal radius fractures using a deep learning technique and compares the predicted parameters with those measured by an orthopedic hand surgeon. Methods: We collected anteroposterior (AP) and lateral X-ray images of 634 wrists in 624 patients with distal radius fractures treated conservatively with a follow-up of at least 2 months. We allocated 507 AP and 507 lateral images to the training set (80% of the images were used to train the model, and 20% were utilized for validation) and 127 AP and 127 lateral images to the test set. The margins of the radius and ulna were annotated for ground truth, and the scaphoid in the lateral views was annotated in the box configuration to determine the volar side of the images. Radius segmentation was performed using attention U-Net, and the volar/dorsal side was identified using a detection and classification model based on RetinaNet. The proposed algorithm measures the radial inclination, dorsal or volar tilt, and radial height by index axes and points from the segmented radius and ulna. Results: The segmentation model for the radius exhibited an accuracy of 99.98% and a Dice similarity coefficient (DSC) of 98.07% for AP images, and an accuracy of 99.75% and a DSC of 94.84% for lateral images. The segmentation model for the ulna showed an accuracy of 99.84% and a DSC of 96.48%. Based on the comparison of the radial inclinations measured by the algorithm and the manual method, the Pearson correlation coefficient was 0.952, and the intraclass correlation coefficient was 0.975. For dorsal/volar tilt, the correlation coefficient was 0.940, and the intraclass correlation coefficient was 0.968. For radial height, it was 0.768 and 0.868, respectively. Conclusions: The deep learning-based algorithm demonstrated excellent segmentation of the distal radius and ulna in AP and lateral radiographs of the wrist with distal radius fractures and afforded automatic measurements of radiologic parameters.

Comparison of corticocancellous bone graft from the anterolateral metaphysis of the distal radius versus iliac crest for the treatment of unstable scaphoid nonunion with humpback deformity.

BACKGROUND: Corticocancellous bone grafting from the iliac crest is acceptable treatment for unstable scaphoid nonunion with a viable proximal pole. However, harvesting graft from the iliac crest is associated with donor site morbidity and the requirement of general anesthesia. Thus, bone grafting from the anterolateral metaphysis of the distal radius (DR) can be a treatment option. However, no study has compared the clinical effect between the two grafting techniques. METHODS: From 2014 to 2019, patients with unstable scaphoid nonunion with humpback deformity underwent corticocancellous bone grafting from the anterolateral metaphysis of the DR (group DR) or iliac crest (group IC). Humpback deformity was determined by evaluating the scapholunate angle (SLA) ≥ 60°, intrascaphoid angle (ISA) ≥ 45°, and radiolunate angle (RLA) ≥ 15° from preoperative radiographs and computed tomography scans. The SLA, ISA, and RLA served to gauge carpal alignment. The operative time, grip strength, active range of motion (ROM), the Modified Mayo Wrist score (MMWS), and Disabilities of Arm, Shoulder, and Hand (DASH) score were assessed postoperatively. RESULTS: Thirty-eight patients qualified for the study (group DR, 15; group IC, 23). Union rates did not differ by patient subset (group DR, 100%; group IC, 95.7%; P = .827), and grip strength, ROM, MWS, and DASH score were similar between groups at the last follow-up. The operative time (minutes) was significantly shorter in group DR (median, 98; quartiles, 80, 114) than in group IC (median, 125; quartiles, 105, 150, P < .001). The ISA, RLA, and SLA improved postoperatively in both groups (P < 0.001). The degree of restoring carpal alignment, as evaluated by SLA, showed superior correction capability in group DR (median, 25.3% quartiles, 21.1, 35.3, P < 0.05). Donor site complications were not significantly different between the groups. CONCLUSIONS: Corticocancellous bone graft from the anterolateral metaphysis of the DR for unstable scaphoid nonunion is associated with a shorter operation time and comparable results with that from the iliac crest in regard to union, restoration of carpal alignment, and wrist function. LEVEL OF EVIDENCE: Level III.

3D-assisted corrective osteotomies of the distal radius: a comparison of pre-contoured conventional implants versus patient-specific implants.

PURPOSE: There is a debate whether corrective osteotomies of the distal radius should be performed using a 3D work-up with pre-contoured conventional implants (i.e., of-the-shelf) or patient-specific implants (i.e., custom-made). This study aims to assess the postoperative accuracy of 3D-assisted correction osteotomy of the distal radius using either implant. METHODS: Twenty corrective osteotomies of the distal radius were planned using 3D technologies and performed on Thiel embalmed human cadavers. Our workflow consisted of virtual surgical planning and 3D printed guides for osteotomy and repositioning. Subsequently, left radii were fixated with patient-specific implants, and right radii were fixated with pre-contoured conventional implants. The accuracy of the corrections was assessed through measurement of rotation, dorsal and radial angulation and translations with postoperative CT scans in comparison to their preoperative virtual plan. RESULTS: Twenty corrective osteotomies were executed according to their plan. The median differences between the preoperative plan and postoperative results were 2.6° (IQR: 1.6-3.9°) for rotation, 1.4° (IQR: 0.6-2.9°) for dorsal angulation, 4.7° (IQR: 2.9-5.7°) for radial angulation, and 2.4 mm (IQR: 1.3-2.9 mm) for translation of the distal radius, thus sufficient for application in clinical practice. There was no significant difference in accuracy of correction when comparing pre-contoured conventional implants with patient-specific implants. CONCLUSION: 3D-assisted corrective osteotomy of the distal radius with either pre-contoured conventional implants or patient-specific implants results in accurate corrections. The choice of implant type should not solely depend on accuracy of the correction, but also be based on other considerations like the availability of resources and the preoperative assessment of implant fitting.

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.

Radiographic evaluation of radial flexion osteotomy effect on static scapholunate instability: a preliminary cadaveric study.

INTRODUCTION: The optimal treatment of chronic scapholunate instability has yet to be established. Scapholunate ligament grafts are still far from being the ideal solution. We conducted an experimental study to evaluate whether flexion-opening wedge osteotomy of the distal radius improves misalignment and avoids rotatory subluxation of the scaphoid in a cadaveric model of static scapholunate dissociative instability. MATERIALS AND METHODS: Radiographic studies were performed on 15 cryopreserved specimens after recreating a model of scapholunate instability by division of the scapholunate interosseous ligament (SLIL) and secondary stabilizers, taking radiographs at baseline, after the instability model, and after distal radius osteotomy. Static and dynamic (under controlled tendon traction) anteroposterior and lateral views were obtained to measure the length (in mm) of the carpal scaphoid and scapholunate interval, scapholunate angle, radio-lunate angle, and palmar tilt of the distal joint surface of the radius and to measure the dorsal scaphoid translation by the concentric circles method. The Wilcoxon test was used for statistical comparisons. RESULTS: The scapholunate interval was significantly decreased after osteotomy in all static anteroposterior views and in all lateral views under tendon traction. Dorsal scaphoid translation was significantly reduced in static lateral view in extension and in dynamic lateral view under 5-pound flexor carpi radialis tendon tension controlled by a digital dynamometer. CONCLUSIONS: Flexion-addition osteotomy of the distal radius appears to improve carpal alignment parameters in a cadaveric model of static scapholunate instability, achieving similar values to those obtained before instability.

The effect of forearm rotation on the bone mineral density measurements of the distal radius.

INTRODUCTION: Forearm dual-energy X-ray absorptiometry (DXA) is often performed in clinics where central DXA is unavailable. Accurate bone mineral density (BMD) measurement is crucial for clinical assessment. Forearm rotation can affect BMD measurements, but this effect remains uncertain. Thus, we aimed to conduct a simulation study using CT images to clarify the effect of forearm rotation on BMD measurements. MATERIALS AND METHODS: Forearm CT images of 60 women were analyzed. BMD was measured at the total, ultra-distal (UD), mid-distal (MD), and distal 33% radius regions with the radius located at the neutral position using digitally reconstructed radiographs generated from CT images. Then, the rotation was altered from - 30° to 30° (supination set as positive) with a one-degree increment, and the percent BMD changes from the neutral position were quantified for all regions at each angle for each patient. RESULTS: The maximum mean BMD changes were 5.8%, 7.0%, 6.2%, and 7.2% for the total, UD, MD, and distal 33% radius regions, respectively. The analysis of the absolute values of the percent BMD changes from the neutral position showed that BMD changes of all patients remained within 2% when the rotation was between - 5° and 7° for the total region, between - 3° and 2° for the UD region, between - 4° and 3° for the MD region, and between - 3° and 1° for the distal 33% radius region. CONCLUSION: Subtle rotational changes affected the BMD measurement of each region. The results showed the importance of forearm positioning when measuring the distal radius BMD.

The Vitamin D Metabolite Ratio Is Associated With Volumetric Bone Density in Older Men.

CONTEXT: Serum 25-hydroxyvitamin D (25(OH)D) is the current marker of vitamin D adequacy, but its relationship with bone health has been inconsistent. The ratio of 24,25-dihydroxyvitamin D3 to 25(OH)D3 (vitamin D metabolite ratio or VMR) is a marker of vitamin D that has been associated with longitudinal changes in bone mineral density (BMD) and fracture risk. OBJECTIVE: High-resolution peripheral quantitative computed tomography (HR-pQCT) provides information on bone health beyond standard dual-energy x-ray absorptiometry, in that it measures volumetric BMD (vBMD) as well bone strength. The relationship of the VMR with vBMD and bone strength remains unknown. METHODS: We evaluated the associations of the VMR and 25(OH)D3 with vBMD and bone strength in the distal radius and tibia, assessed by HR-pQCT in 545 older men participating in the Osteoporotic Fractures in Men (MrOS) Study. Primary outcomes were vBMD and estimated failure load (EFL, a marker of bone strength) at the distal radius and tibia. RESULTS: The mean age was 84 ± 4 years, 88.3% were White, and 32% had an estimated glomerular filtration rate <60 mL/min/1.73 m2. In adjusted models, each twofold higher VMR was associated with a 9% (3%, 16%) higher total vBMD and a 13% (5%, 21%) higher EFL at the distal radius. Results were similar at the distal tibia. 25(OH)D3 concentrations were not associated with any of the studied outcomes. CONCLUSION: Among older men, a higher VMR was associated with greater vBMD and bone strength while 25(OH)D3 was not. The VMR may serve as a valuable marker of skeletal health in older men.