Vertebral Artery Variations at the Craniovertebral Junction in “Sandwich” Atlantoaxial Dislocation Patients

Objective: To summarize the vertebral artery (VA) pattern of 96 “sandwich” atlantoaxial dislocation (AAD) patients and to describe the strategies of reducing the injury of VA during surgery.Methods: From 2009 to 2020, we retrospectively reviewed the 3-dimensional computed tomography angiography data of 96 AAD patients combined with atlas occipitalization and C2–3 fusion, which were diagnosed as “sandwich” AAD and 96 patients as control group patients who were without atlas occipitalization, C2–3 fusion and any other cervical bone deformity at our institution. The variations of each side of VA were described in 3 different parts (C0–1, C1–2, and C2–3) according to the characteristics of the 3-part pathological structures in “sandwich” subgroup.Results: One hundred ninety-two sides of VAs in every group of patients were analyzed and every VA was described separately at 3 different level regions. There were different variations in these 3 different regions: 4 variations in the upper fusion region, 5 variations in the sandwiched region, and 6 variations in the lower fusion region in sandwich AAD patients. And the rate of VA deformity in sandwich AAD patients was much higher and more types of VA variations existed.Conclusion: In “sandwich” AAD patients, deformities of vertebral arteries in craniovertebral junction are more common, and the same VA may have deformities at different levels that severely affect surgical procedures. Therefore, preoperative imaging examination of VA for “sandwich” AAD patients is vital of guiding surgeons to avoid injury of VA during surgery.

Bone Deformity due to Rickets and Osteomalacia in Children and Adolescents

Rickets is a worldwide bone disease that is associated with disorders of calcium and phosphate homeostasis and can lead to short stature and joint deformities. Osteomalacia is a major metabolic bone disease that results from a chronic and severe deficiency of vitamin D or phosphate from any cause after growth has stopped. A deficiency of vitamin D or phosphate leads to defective bone mineralization and generalized or localized vague bone pain in various parts of the skeleton and / or proximal muscle weakness. Rickets and osteomalacia are two different clinical diseases with impaired bone mineralization. Rickets occurs throughout the growing skeleton in infants and children, while osteomalacia occurs in adults after fusion of the growth plates. Rickets and osteomalacia are increasingly common in Saudi Arabia, with vitamin D deficiency being the most common etiological cause. Early skeletal deformities can occur in infants, such as soft, thin skull bones, a condition known as craniotabes. In adults, as a result of demineralization, the bones become less rigid (soft bone) with pathological fractures. The diagnosis of both diseases is based on the medical history and physical examination, radiological characteristics, and biochemical tests. Management depends on the underlying etiology.

A Neglected Case of Wilson’s Disease Presenting as Symptomatic Urolithiasis and Proteinuria

We report a short-statured, 39-year-old male presenting with recurrent kidney stones, history of refractory rickets, and bone deformity. He had been consuming multiple doses of calcium supplements and multiple courses of vitamin D over past 30 years beforeprior to reporting in our clinic without any significant laboratory or clinical improvement. The patient was diagnosed as having Fanconi’s syndrome attributable to Wilson’s disease. This patient highlighted that in case of resistant rickets, a high index of uncertainty must be invoked for Wilson’s disease. Appropriate timely recognition of this entity results in prompt ministrations and prevention of disability. We also presented and discussed reviews on Wilson’s disease from literature.

METABOLIC AND ORTHOPEDIC ASPECT OF X-LINKED VITAMIN D-RESISTANT HYPOPHOSPHATEMIC RICKETS

INTRODUCTION: - The X-linked vitamin D-resistant hypophosphatemic rickets (VDXLR) is a metabolic disorder. Medication treatment consists of oral phosphate substitution and supplementation of active vitamin D compounds. Our study aimed to review our patients with VDXLR, focusing on those undergoing surgery, mainly lengthening procedures. The main parameters of interest were growth, height, the axis of the lower limbs, pain, and degenerative arthropathy. METHODS: - Twelve patients with VDXLR were followed at our institution. Eight patients underwent surgical correction, and three of them in combination with bone lengthening. The corrections were executed at the end of growth in the patients. Clinical end points were height, leg axis, and pain. RESULTS: - Single bilateral surgical correction was performed in six patients; one patient had three and ve corrections. Bone lengthening was performed in three patients. At the last follow-up, the height of seven operated patients was within normal range. In addition, the leg axis was normalized in six patients with mild genua vara in two. Bone healing was excellent, and no surgical complications. There was no one radiological evidence of degenerative arthropathy. CONCLUSIONS: - In case of bone deformity, surgery can safely be performed, independent of age or bone maturation. All patients were happy with the outcomes of axial corrective surgery and bone lengthening, and in the majority. Only one corrective intervention was needed.

How to manage pes cavus in children and adolescents?

Pes cavus in its different forms is not a pathological entity, but rather the manifestation of multiple diseases. Cavovarus, a form of cavus foot, should never be considered a physiological deformity. A neurological condition should always be excluded. The evolution of pes cavovarus is unpredictable because of the large number of conditions involved in its aetiology, as well as their variable degree of expression. About 66% of cavovarus feet are the result of subtle neurological diseases, which only become evident later in life. Although surgery may not change quality of life, recent studies suggest that it may improve foot posture and reduce walking instability. The aim of treatment is to preserve a painless, plantigrade, mobile foot. Management consists of correcting bone deformity while preserving movement, and the wise use of rebalancing techniques. Arthrodesis should only be a salvage procedure. Cite this article: EFORT Open Rev 2021;6:510-517. DOI: 10.1302/2058-5241.6.210021

Zebrafish mafbb Mutants Display Osteoclast Over-Activation and Bone Deformity Resembling Osteolysis in MCTO Patients

Multicentric carpotarsal osteolysis (MCTO) is a rare skeletal dysplasia with osteolysis at the carpal and tarsal bones. Heterozygous missense mutations in the transcription factor MAFB are found in patients with MCTO. MAFB is reported to negatively regulate osteoclastogenesis in vitro. However, the in vivo function of MAFB and its relation to MCTO remains unknown. In this study, we generated zebrafish MAFB homolog mafbb mutant utilizing CRISPR/Cas9 technology. Mafbb deficient zebrafish demonstrated enhanced osteoclast cell differentiation and abnormal cartilage and bone development resembling MCTO patients. It is known that osteoclasts are hematopoietic cells derived from macrophages. Loss of mafbb caused selective expansion of definitive macrophages and myeloid cells, supporting that mafbb restricts myeloid differentiation in vivo. We also demonstrate that MAFB MCTO mutations failed to rescue the defective osteoclastogenesis in mafbb−/− embryos, but did not affect osteoclast cells in wild type embryos. The mechanism of MCTO mutations is likely haploinsufficiency. Zebrafish mafbb mutant provides a useful model to study the function of MAFB in osteoclastogenesis and the related MCTO disease.

Tomographic Analysis of Positioning of Reverse Baseplates Positioning

Objective To verify whether reverse baseplate positioning without the support of intraoperative three-dimensional technology is within the acceptable parameters in the literature and whether glenoid bone deformity (GBD) compromises this positioning. Methods Sixty-nine reverse shoulder arthroplasties were evaluated with volumetric computed tomography (CT). Two radiologists performed blinded CT scan analysis and evaluated baseplate position within 2mm of the inferior glenoid; the inclination and version of the baseplate in relation to the Friedman line; and upper and lower screw and baseplate metallic peg end point positionings. The patients were divided according to the presence of GBD for statistical analyses. Results The two radiologists concurred reasonably in their interpretations of the following analyzed parameters: baseplate position within 2mm of the inferior glenoid rim (97.1% and 95.7%), baseplate inclination (82.6% and 81.2%), baseplate version (69.6% and 56.5%), the upper screw reaching the base of the coracoid process (71% and 79.7%), the inferior screw remaining inside the scapula (88.4% and 84.1%), and the metallic peg of the baseplate considered intraosseous (88.4% and 72.5%). Conclusion Reverse baseplate positioning without intraoperative three-dimensional technology is within the acceptable parameters of the literature, except for baseplate version and upper screw position. GBD did not interfere with baseplate positioning in reverse shoulder arthroplasty.