Camilo Osorio

Articular cartilage phenotypic homeostasis is crucial for life‐long joint function, but the underlying cellular and molecular mechanisms governing chondrocyte stability remain poorly understood. Here, we show that the protein tyrosine phosphatase SHP2 is differentially expressed in articular cartilage (AC) and growth plate cartilage (GPC) and that it negatively regulates cell proliferation and cartilage phenotypic program. Postnatal SHP2 deletion in Prg4 ⁺ AC chondrocytes increased articular cellularity and thickness, whereas SHP2 deletion in Acan ⁺ pan‐chondrocytes caused excessive GPC chondrocyte proliferation and led to joint malformation post‐puberty. These observations were verified in mice and in cultured chondrocytes following treatment with the SHP2 PROTAC inhibitor SHP2D26. Further mechanistic studies indicated that SHP2 negatively regulates SOX9 stability and transcriptional activity by influencing SOX9 phosphorylation and promoting its proteasome degradation. In contrast to published work, SHP2 ablation in chondrocytes did not impact IL‐1‐evoked inflammation responses, and SHP2's negative regulation of SOX9 could be curtailed by genetic or chemical SHP2 inhibition, suggesting that manipulating SHP2 signaling has translational potential for diseases of cartilage dyshomeostasis.

» Adjacent segment disease is characterized by a degenerative process adjacent to a previously fused spine segment, with new onset of clinical symptoms such as radiculopathy, myelopathy, or instability. » Etiology is related to the natural history of the disease process, increased biomechanical stress at adjacent segments, clinical factors specific to the individual patient, intraoperative factors, and malalignment. » Treatment is usually nonoperative, but surgical intervention can be indicated. Decompression and fusion remain the mainstay of operative treatment, and isolated decompression should be considered in specific cases. » Further randomized controlled trials are needed to establish how the treatment should progress, particularly with the development of minimally invasive and endoscopic surgery.

» Lateral decubitus positioning is a nonanatomical position used for multiple orthopaedic procedures to obtain adequate surgical exposure. » Unique ophthalmologic, musculoskeletal, neurovascular, and hemodynamic complications may arise inadvertently from positioning. » Orthopaedic surgeons should be aware of the possible complications that may manifest from placing patients in the lateral decubitus position to adequately prevent and to properly manage them.

Antibiotic bone cement (ABC) is an effective tool for the prophylaxis and treatment of osteomyelitis due to the controlled, sustained release of local antibiotics. ABC has been proven to be effective in the orthopedic fields of arthroplasty and extremity trauma, but the adoption of ABC in spine surgery is limited. The characteristics of ABC make it an optimal solution for treating vertebral osteomyelitis (VO), a serious complication following spine surgery, typically caused by bacterial and sometimes fungal and parasitic pathogens. VO can be devastating, as infection can result in pathogenic biofilms on instrumentation that is dangerous to remove. New techniques, such as kyphoplasty and novel vertebroplasty methods, could amplify the potential of ABC in spine surgery. However, caution should be exercised when using ABC as there is some evidence of toxicity to patients and surgeons, antibiotic allergies, bone cement structural impairment, and possible development of antibiotic resistance. The purpose of this article is to describe the basic science of antibiotic cement utilization and review its usage in spine surgery.

Surgical robots were invented in the 1980s, and since then, robotic-assisted surgery has become commonplace. In the field of spine surgery, robotic assistance is utilized mainly to place pedicle screws, and multiple studies have demonstrated that robots can increase the accuracy of screw placement and reduce radiation exposure to the patient and the surgeon. However, this may be at the cost of longer operative times, complications, and the risk of errors in mapping the patient’s anatomy.