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Introduction: Diabetes mellitus (DM) impairs fracture healing and is associated with susceptibility to infection, which further inhibits fracture healing. While intermittent parathyroid hormone (1-34) (iPTH) effectively improves fracture healing, it is unknown whether infection-associated impaired fracture healing can be rescued with PTH (teriparatide). Methods: A chronic diet-induced type 2 diabetic mouse model was used to yield mice with decreased glucose tolerance and increased blood glucose levels compared to lean-fed controls. Methicillin-resistant Staphylococcus aureus (MRSA) was inoculated in a surgical tibia fracture model to simulate infected fracture, after which mice were treated with a combination of antibiotics and adjunctive teriparatide treatment. Fracture healing was assessed by Radiographic Union Scale in Tibial Fractures (RUST), micro-computed tomography (mCT), biomechanical testing, and histology. Results: RUST score was significantly poorer in diabetic mice compared to their lean nondiabetic counterparts. There were concomitant reductions in micro-computed tomography (mCT) parameters of callus architecture including bone volume/total volume, trabecular thickness, and total mineral density in type 2 diabetes mellitus (T2DM) mice. Biomechanicaltesting of fractured femora demonstrated diminished torsional rigidity, stiffness, and toughness to max torque. Adjuvant teriparatide treatment with systemic antibiotic therapy improved numerous parameters of bone microarchitecture bone volume, increased connectivity density, and increased trabecular number in both the lean and T2DM group. Despite the observation that poor fracture healing in T2DM mice was further impaired by MRSA infection, adjuvant iPTH treatment significantly improved fracture healing compared to antibiotic treatment alone in infected T2DM fractures. Discussion: Our results suggest that teriparatide may constitute a viable adjuvant therapeutic agent to improve bony union and bone microarchitecture to prevent the development of septic nonunion under diabetic conditions. [ABSTRACT FROM AUTHOR]

Background: The Latarjet procedure is effective for patients with anterior glenohumeral instability with substantial glenoid bone loss due to its triple blocking effect. Indications: Indications include high-risk patients with recurrent anterior glenohumeral instability with any glenoid bone loss or low-risk patients with 15% to 30% glenoid bone loss. Technique Description: An incision is made lateral to the coracoid and the deltopectoral interval is established. The pectoralis minor is released medially off the coracoid and the coracoacromial (CA) ligament is released close to the acromion. The coracoid is cut with a right-angle saw and the inferior coracoid is decorticated with a burr. Two holes are pre-drilled in the coracoid. The subscapularis is split between the upper two-thirds and lower one-third with the arm in external rotation. The capsule is split vertically at the joint line and the humeral head is retracted. The anterior glenoid is decorticated with a burr, and a hole is drilled inferiorly. The depth is measured and added to the depth of the inferior bone block hole. A fully threaded 3.5-mm solid stainless steel screw is placed in the inferior hole. Care is taken to ensure that the lateral border of the bone block is flush with the articular margin. This is repeated for the superior hole. A 1.8-mm knotless suture anchor is placed between the screws. The repair stitch is passed through the capsule and loaded onto the anchor and tensioned. The CA ligament is laid over the capsule and repaired. The subscapularis split is repaired side to side and the wound is closed in layers. Results: High return-to-sport rates, including at the same level of play, have been observed among young competitive athletes with significant glenoid bone loss who underwent a Latarjet, with similarly favorable results in older patients. Ninety-day complication rates have been reported around 9%, 5% of which constituted graft or hardware failures. Discussion/Conclusion: The Latarjet procedure is an effective option for indicated patients with anterior glenohumeral instability and may be enhanced with solid screws, proper anatomic technique, and capsulolabral repair augmentation. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication. [ABSTRACT FROM AUTHOR]

Fracture healing is impaired in the setting of infection, which begets protracted inflammation. The most problematic causative agent of musculoskeletal infection is methicillin‐resistant Staphylococcus aureus (MRSA). We hypothesized that modulation of excessive inflammation combined with cell‐penetrating antibiotic treatments facilitates fracture healing in a murine MRSA‐infected femoral fracture model. Sterile and MRSA‐contaminated open transverse femoral osteotomies were induced in 10‐week‐old male C57BL/6 mice and fixed via intramedullary nailing. In the initial therapeutic cohort, empty, vancomycin (V), rifampin (R), vancomycin‐rifampin (VR), or vancomycin‐rifampin‐trametinib (VRT) hydrogels were applied to the fracture site intraoperatively. Rifampin was included because of its ability to penetrate eukaryotic cells to target intracellular bacteria. Unbiased screening demonstrated ERK activation was upregulated in the setting of MRSA infection. As such, the FDA‐approved mitogen‐activated protein kinase kinase (MEK)1‐pERK1/2 inhibitor trametinib was evaluated as an adjunctive therapeutic agent to selectively mitigate excessive inflammation after infected fracture. Two additional cohorts were created mimicking immediate and delayed postoperative antibiotic administration. Systemic vancomycin or VR was administered for 2 weeks, followed by 2 weeks of VRT hydrogel or oral trametinib therapy. Hematologic, histological, and cytokine analyses were performed using serum and tissue isolates obtained at distinct postoperative intervals. Radiography and micro‐computed tomography (μCT) were employed to assess fracture healing. Pro‐inflammatory cytokine levels remained elevated in MRSA‐infected mice with antibiotic treatment alone, but increasingly normalized with trametinib therapy. Impaired callus formation and malunion were consistently observed in the MRSA‐infected groups and was partially salvaged with systemic antibiotic treatment alone. Mice that received VR alongside adjuvant MEK1‐pERK1/2 inhibition displayed the greatest restoration of bone and osseous union. A combinatorial approach involving adjuvant cell‐penetrating antibiotic treatments alongside mitigation of excessive inflammation enhanced healing of infected fractures. © 2022 American Society for Bone and Mineral Research (ASBMR). [ABSTRACT FROM AUTHOR]

Case: A 7-year-old boy was found to have Ewing sarcoma of the left tibia. The sarcoma was resected, and the defect was reconstructed using a humeral head allograft and intramedullary limb-lengthening nail. Conclusions: Limb-salvage reconstruction in children can be complicated by the sacrifice of epiphyseal plates and limblength discrepancies and thus requires techniques tailored to each case. [ABSTRACT FROM AUTHOR]

Medial quadriceps tendon-femoral ligament (MQTFL) reconstruction for prevention of recurrent patella dislocation is an alternative to medial patellofemoral ligament (MPFL) reconstruction. Because the reconstruction graft attaches to the quadriceps tendon, no patella drill hole is required, thereby eliminating iatrogenic fracture risk. The procedure remains anatomically accurate and early results are comparable to MPFL reconstruction for preventing patella dislocation. The MQTFL reconstruction graft is brought up under the vastus medialis obliquus distal to the patella apex, such that its orientation is directed toward the medial patellofemoral complex (MPFC) midpoint, also known as Tanaka's point. The graft is then secured by looping it around the vastus medialis and rectus femoris tendons, after which optimal graft length is easily established by cycling the knee, after which it is sutured securely into the deep quadriceps tendon precisely at the anatomic midpoint of the MPFC. Anatomic reconstruction of the MQTFL-in which graft orientation is crucial-confers reliable patellofemoral joint stability in the surgical treatment of patients with recurrent patella dislocations., (© 2021 The Authors.)