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This study compared the effect of undifferentiated adipose-derived stem cells (ADSCs) vs tacrolimus (FK506) in peripheral nerve regeneration in a rat sciatic nerve complete transection model. Forty Wistar rats were equally distributed in four groups. In the SHAM surgery group, the sciatic nerve was exposed and no further intervention was done. In the conduit-alone group (the SLN group), a 10-mm nerve gap was created and bridged with a fibrin conduit filled in with normal saline. In the FK506 group, the fibrin conduit was injected with soluble FK506. In the ADSC group, the conduit was impregnated with undifferentiated ADSCs. Nerve regeneration was assessed by means of walking track analysis, electromyography, and neurohistomorphometry. Clinically and microscopically, nerve regeneration was achieved in all groups at 12 weeks. Walking track analysis confirmed functional recovery in the FK506 and ADSC groups, but there was no difference between them. Recovery in function was also achieved in the SLN group, but it was inferior (P<.05). Electromyography demonstrated superior nerve regeneration in the FK506 and ADSC groups compared with the SLN group (P<.05), with no difference between the FK506 and ADSC groups. Similarly, histology showed no difference between the FK506 and ADSC groups, although both outperformed the SLN group (P<.05). No complications were observed. Successful peripheral nerve regeneration can be accomplished after a 10-mm nerve defect treated with nerve conduits. Superior nerve regeneration may be expected when the conduits are loaded with undifferentiated ADSCs or FK506, with similar outcomes for ADSCs and FK506. [Orthopedics. 2023;46(6):e353–e361.] [ABSTRACT FROM AUTHOR]

Scientific misconduct (fraud) in medical writing is an important and not infrequent problem for the scientific community. Although noteworthy examples of fraud surface occasionally in the media, detection of fraud in medical publishing is generally not as straightforward as one might think. National bodies on ethics in science, strict selection criteria, a robust peer-review process, careful statistical validation, and anti-plagiarism and image-fraud detection software contribute to the production of high-quality manuscripts. This article reviews the various types of fraud in medical writing, discusses the related literature, and describes tools journals implement to unmask fraud. [Orthopedics. 2018; 41(2):e176–e183]. [ABSTRACT FROM AUTHOR]

The authors reviewed the files of all patients with chordomas who were admitted and treated at their institutions from 1975 to 2012. Patients were categorized by early local recurrence and metastasis. Aggressive clinical behavior was defined as local recurrence and metastasis within 24 months of diagnosis and adequate treatment (wide en bloc resection with microscopically negative tumor margins). According to these criteria, 13 patients (14.3%) had aggressive chordomas, including 7 men and 6 women, with mean age of 54 years (range, 37-65 years) at diagnosis and treatment. All patients had preoperative tumor biopsy, followed by resection with partial (7 patients) or total sacrectomy (6 patients). In all cases, biopsy and histologic analysis of resected tumor specimens showed conventional chordomas. Resection margins were wide (grossly negative) in 6 patients and wide contaminated in 7 patients. Mean maximum tumor diameter was 11.8 cm (range, 5-21 cm). Mean follow-up was 43 months (range, 8-131 months). Rates of local recurrence, metastasis, and death were evaluated. At the last follow-up, all patients had local recurrence at a mean of 13 months (range, 5-22 months). Histologic examination of recurrent tumors showed a dedifferentiated chordoma with a fibrosarcoma component in 2 patients and no histologic change in the remaining patients. In addition, 8 patients had metastases at a mean of 13 months (range, 4-24 months) and died of their disease. All histologic findings of metastatic lesions were similar to those of primary tumors. Early diagnosis of aggressive tumors requires close follow-up of patients with chordomas. Metastasis is common, with resultant poor survival. [Orthopedics. 2017; 40(2):e248-e254.]. [ABSTRACT FROM AUTHOR]

Peripheral nerve injury can have a potentially devastating impact on a patient's quality of life, resulting in severe disability with substantial social and personal cost. Refined microsurgical techniques, advances in peripheral nerve topography, and a better understanding of the pathophysiology and molecular basis of nerve injury have all led to a decisive leap forward in the field of translational neurophysiology. Nerve repair, nerve grafting, and nerve transfers have improved significantly with consistently better functional outcomes. Direct nerve repair with epineural microsutures is still the surgical treatment of choice when a tension-free coaptation in a well-vascularized bed can be achieved. In the presence of a significant gap (>2-3 cm) between the proximal and distal nerve stumps, primary end-to-end nerve repair often is not possible; in these cases, nerve grafting is the treatment of choice. Indications for nerve transfer include brachial plexus injuries, especially avulsion type, with long distance from target motor end plates, delayed presentation, segmental loss of nerve function, and broad zone of injury with dense scarring. Current experimental research in peripheral nerve regeneration aims to accelerate the process of regeneration using pharmacologic agents, bioengineering of sophisticated nerve conduits, pluripotent stem cells, and gene therapy. Several small molecules, peptides, hormones, neurotoxins, and growth factors have been studied to improve and accelerate nerve repair and regeneration by reducing neuronal death and promoting axonal outgrowth. Targeting specific steps in molecular pathways also allows for purposeful pharmacologic intervention, potentially leading to a better functional recovery after nerve injury. This article summarizes the principles of nerve repair and the current concepts of peripheral nerve regeneration research, as well as future perspectives. [Orthopedics. 2017; 40(1):e141-e156.]. [ABSTRACT FROM AUTHOR]

Pertrochanteric fractures in elderly patients represent a major health issue. The available surgical options are fixation with extramedullary devices, intramedullary nailing, and arthroplasty. Intramedullary nailing for hip fractures has become more popular in recent years. Advantages of intramedullary nailing for hip fracture fixation include a more efficient load transfer due to the proximity of the implant to the medial calcar, less implant strain and shorter lever arm because of its closer positioning to the mechanical axis of the femur, significantly less soft tissue disruption and periosteal stripping of the femoral cortex, shorter operative time and hospital stay, fewer blood transfusions, better postoperative walking ability, and lower rates of leg-length discrepancy. Compromise of the posteromedial cortex and/or the lateral cortex, a subtrochanteric extension of the fracture, and a reversed obliquity fracture pattern represent signs of fracture instability, warranting the use of intramedullary nailing. However, the use of intramedullary nailing, with its unique set of clinical implications, has introduced a new set of complications. The reported complications include malalignment, cutout, infection, false drilling, wrong lag screw length and drill bit breakage during the interlocking procedure, external or internal malrotation (≥20°) of the femoral diaphysis, elongation of the femur (2 cm), impaired bone healing, periprosthetic fracture distal to the tip of the nail, fracture collapse, implant failure, lag screw intrapelvic migration, neurovascular injury, secondary varus deviation, complications after implant removal, trochanteric pain, and refracture. Many of these complications are related to technical mistakes. This article reviews intramedullary nailing for the treatment of pertrochanteric femoral fractures, with an emphasis on complications. [ABSTRACT FROM AUTHOR]