Lubricin is an important boundary lubricant and chondroprotective glycoprotein in synovial fluid. Both increased and decreased synovial fluid lubricin concentrations have been reported in experimental post-traumatic osteoarthritis (PTOA) animal models and in naturally occurring joint injuries in humans and animals, with no consensus about how lubricin is altered in different species or injury types. Increased synovial fluid lubricin has been observed following intra-articular fracture in humans and horses and in human late-stage osteoarthritis; however, it is unknown how synovial lubricin is affected by knee-destabilizing injuries in large animals. Spontaneous rupture of cranial cruciate ligament (RCCL), the anterior cruciate ligament equivalent in quadrupeds, is a common injury in dogs often accompanied by OA. Here, clinical records, radiographs, and synovial fluid samples from 30 dogs that sustained RCCL and 9 clinically healthy dogs were analyzed. Synovial fluid lubricin concentrations were nearly 16-fold greater in RCCL joints as compared to control joints, while IL-2, IL-6, IL-8, and TNF-α concentrations did not differ between groups. Synovial fluid lubricin concentrations were correlated with the presence of radiographic OA and were elevated in three animals sustaining RCCL injury prior to the radiographic manifestation of OA, indicating that lubricin may be a potential biomarker for early joint injury.
- Award ID(s):
- 1719875
- NSF-PAR ID:
- 10325586
- Date Published:
- Journal Name:
- Veterinary and Comparative Orthopaedics and Traumatology
- Volume:
- 35
- Issue:
- 02
- ISSN:
- 0932-0814
- Page Range / eLocation ID:
- 090 to 095
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Lateral ankle sprains are a common musculoskeletal injury. The anterior talofibular ligament (ATFL) is the primary ligament involved and is assessed via an anterior drawer test. Clinically assessing joint laxity has been a subjective task. Evaluating both magnitude of translation and quality of the endfeel has presented challenges. Until recently, a reliable and valid arthrometer to test joints other than the knee has not been available. The Mobil-Aider arthrometer has undergone bench testing for validity, reliability testing in healthy persons, and most recently the testing of participants for pathology. A summary of these studies is available in the Online Supplement . The goal of this study was to determine the ability of the arthrometer to objectively identify the anterior translation of the ankle and the relationship to the clinical diagnosis. The participant was evaluated by a physician and magnitude of ankle sprain was determined. An arthrometer was used to perform an anterior drawer test (uninjured before injured, 3 measures each) in the prone position. Both clinicians were blinded to the data of the other. There were 30 participants, 10 per group (uninjured, 1° sprain, 2° sprain). Mann-Whitney U testing found significant differences between the control and grade 1 ankle sprain groups ( P < .001), the control and grade 2 ankle sprain groups ( P < .001), and the grade 1 and grade 2 ankle sprain groups ( P = .004). There was ± 0.31 mm difference in anterior translation between healthy ankles, whereas there was 1.11 mm and 2.16 mm difference between ankles in grade 1 and grade 2 sprains, respectively. The anterior drawer test is the gold standard for clinical ATFL testing, but the subjective nature of this test poses challenges. Technology is available to assess ankle joint laxity and enhance the objectivity of patient assessment and throughout the recovery process. An arthrometer is a valuable tool in quantifying orthopaedic examination.
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INTRODUCTION: In practice, the use of a whip stitch versus a locking stitch in anterior cruciate ligament (ACL) graft preparation is based on surgeon preference. Those who prefer efficiency and shorter stitch time typically choose a whip stitch, while those who require improved biomechanical properties select a locking stitch, the gold standard of which is the Krackow method. The purpose of this study was to evaluate a novel suture needle design that can be used to perform two commonly used stitch methods, a whip stitch, and a locking stitch, by comparing the speed of graft preparation and biomechanical properties. It was hypothesized that adding a locking mechanism to the whip stitch would improve biomechanical performance but would also require more time to complete due to additional steps required for the locking technique. 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