Regulatory role of NFAT1 signaling in articular chondrocyte activities and osteoarthritis pathogenesis.

Osteoarthritis (OA), the most common form of joint disease, is characterized clinically by joint pain, stiffness, and deformity. OA is now considered a whole joint disease; however, the breakdown of the articular cartilage remains the major hallmark of the disease. Current treatments targeting OA symptoms have a limited impact on impeding or reversing the OA progression. Understanding the molecular and cellular mechanisms underlying OA development is a critical barrier to progress in OA therapy. Recent studies by the current authors' group and others have revealed that the nuclear factor of activated T cell 1 (NFAT1), a member of the NFAT family of transcription factors, regulates the expression of many anabolic and catabolic genes in articular chondrocytes of adult mice. Mice lacking NFAT1 exhibit normal skeletal development but display OA in both appendicular and spinal facet joints as adults. This review mainly focuses on the recent advances in the regulatory role of NFAT1 transcription factor in the activities of articular chondrocytes and its implication in the pathogenesis of OA.

Retrospective chart review: Weightbearing CT scans and the measurement of the Lisfranc ligamentous complex.

BACKGROUND: Lisfranc Ligamentous Complex (LLC) injuries are commonly misdiagnosed due to their unreliable projection on plain films. Weightbearing CT (WBCT) scans are a relatively new imaging modality that has not yet been utilized to establish widely referenced baseline anatomic positions. METHODS: A retrospective chart review was conducted of patients who had undergone weightbearing CT of the bilateral lower extremities with one-hundred and twelve being included (56 patients). Measurements of the Lisfranc joint were collected by two independent reviewers. Uninjured symmetric anatomy was used to describe a baseline for normal anatomic variation and to evaluate for sex-based or age-related differences. These measurements were then compared against the injured side. RESULTS: In patients without Lisfranc injury, the 1st metatarsal base to 2nd metatarsal base distance (Base M1-M2) was 2.7 + /- 0.7 mm; 2nd metatarsal base to medial cuneiform (M2-C1) was 3.7 + /- 0.7 mm; intercuneiform distance was 1.2 + /- 0.3 mm; and sagittal descent 12.2 + /- 5.4 mm. Patients with injury to LLC had a larger M1-M2 base distance (Δ = 0.5903, p < 0.0001) and M2-C1 interval (Δ = 1.8008, p < 0.0001) compared to uninjured side. Males had significantly higher M2-C1 (p = 0.0031), intercuneiform distance (p = 0.0039), and sagittal descent (p = 0.0008) compared to female patients. No significant differences were found between left versus right side in any of the measurements. Intercuneiform distance (p = 0.0039) was found to significantly decrease as age increased, while sagittal descent significantly increased with increased age (p = 0.0066). CONCLUSION: Weightbearing CT has high utility in identification of Lisfranc injuries particularly when comparing injured and uninjured sides, which may be its greatest utility in defining injuries. This is evident in the excellent diagnostic ability of the M2-C1 measurement. By defining baseline anatomic measurements for Lisfranc complex parameters in our patient population, we provide normal parameters for comparison when evaluating potential subtle injuries. LEVEL OF EVIDENCE: III.

Anomalous Flexor Digitorum Profundus Muscle Bellies as a Cause of Snapping Wrist and Carpal Tunnel Syndrome: A Case Report.

CASE: A 20-year-old right hand dominant woman presented with an audible and painful snapping wrist occurring with finger flexion. This bothersome mechanical finding and concomitant carpal tunnel syndrome (CTS) did not resolve with conservative measures. Dynamic magnetic resonance imaging revealed anomalous flexor digitorum profundus (FDP) muscle bellies as the cause of the mechanical snapping and irritation of the median nerve. Carpal tunnel release and excision of anomalous muscle within the carpal tunnel and distal forearm provided complete resolution of symptoms. CONCLUSION: Anomalous muscle bellies of the FDP is a rare cause of a volar snapping wrist and CTS.

Effect of Tranexamic Acid on Wound Complications and Blood Loss in Total Ankle Arthroplasty.

BACKGROUND: Tranexamic acid (TXA) is a medication that has been shown to decrease blood loss and risk of blood transfusion in total knee and total hip arthroplasty. The purpose of this study was to evaluate the use of TXA in patients undergoing total ankle arthroplasty (TAA). We hypothesized there would be less blood loss and wound complications in patients receiving TXA. METHODS: A retrospective review of 2 patient cohorts operated on by 2 surgeons was performed from 2010 to 2018. We compared a group of TAA patients that did not receive TXA vs a subsequent group that received TXA. Patients received 1g intravenous TXA before the tourniquet was inflated followed by another 1 g after release of the tourniquet. Intraoperative blood loss was recorded and preoperative hemoglobin and hematocrit levels were compared to postoperative levels. Intraoperative and postoperative complications were compared between the 2 groups. A total of 119 patients were included in the study, of whom 55 received TXA. No significant difference existed between the 2 groups in gender, age, body mass index, or Charlson comorbidity index. RESULTS: There was no difference in estimated blood loss, postoperative hemoglobin/hematocrit values or preoperative to postoperative change in hemoglobin/hematocrit values. Additionally, there was no difference in wound complications or overall complication rate between the groups. CONCLUSION: TXA has been shown to be effective in total knee and total hip arthroplasty in decreasing blood loss and transfusion risk. We did not find it to be effective in reducing intraoperative blood loss, perioperative blood loss, or wound complications in TAA. LEVEL OF EVIDENCE: Level III, comparative study.

Surgical Gowning Technique: Are We Contaminated Before We Cut?

OBJECTIVES: To assess possible breaches of sterility during the initial gowning step. DESIGN: Observational study. Twenty-seven gowning events were monitored for contamination during a simulated two-person gowning process in which a surgical technician assists a surgeon in the gowning process at the beginning of a surgical procedure. The lower portion of the technician's gown was coated with resin powder before the gowning process to simulate contamination. SETTING: Single-institution Level 1 trauma center. PARTICIPANTS: Three physicians and 3 tenured surgical technicians. INTERVENTION: Observed contaminated areas represented by ultraviolet resin powder under ultraviolet light on the gown of the surgeon after the two-person gowning step. MAIN OUTCOME MEASUREMENT: Number and surface area of contamination events. RESULTS: There was a 66.67% rate of contamination of the surgeon's gown sleeves while being gowned by a surgical technician. The overall median contamination for the short surgeon was 1.3 cm. For the medium height surgeon, the overall median contamination was 1.4 cm. The tall surgeon had an overall median contamination of 2.9 cm. Of the short, medium, and tall surgeons, the number of contamination events was 6, 5, and 7, respectively. The study suggested that the surgeon's height was a significant source of variation (P = 0.046). CONCLUSION: We present an observational pilot study that suggests that to reduce contamination in the operating room, the two-person method must be highly monitored. This study also proposes that the single-person gowning technique should be used to reduce contamination rate during the gowning process.