Megan H. Cortazzo

The use of platelet-rich plasma for the treatment of osteoarthritis.

Abstract Osteoarthritis (OA) is the most common cause of disability in the United States. With an aging population, its incidence is only likely to rise. Articular cartilage has a poor capacity to heal. The advent of regenerative medicine has heralded a new approach to early treatment of degenerative conditions such as osteoarthritis by focusing on regenerating damaged tissue rather than focusing on replacement. Platelet-rich plasma (PRP) is one such treatment that has received much recent attention and has been used particularly for tendon healing. Recent studies have focused on assessing its use on degenerative conditions such as OA. In this article, we review the evidence for the pathologic basis for the use of PRP in OA and also the clinical outcomes pertaining to its use. Finally, we also consider reasons for the inconsistent clinical success pertaining to its use.

Vitamin K: Fracture Prevention and Beyond

Morbidity and decreased function related to osteoporosis, fracture, cardiovascular disease, stroke, and peripheral vascular disease are encountered by clinicians daily. Although we have seen vast advancement in treatment and management of these conditions, preventative practice has unfortunately served a lesser role in patient care. Increasing the dietary intake of vitamin K may have substantial utility in the prevention of these disease states. Since the discovery of vitamin K in 1935, its primary role was thought to be involved in the synthesis of clotting factors II, VII, IX, and X. Recently, its function in other metabolic pathways has emerged, leading to exploration of its significance beyond coagulation. Vitamin K is essential to bone physiology and prevention of atherosclerosis. It is involved in bone remodeling, cell signaling, apoptosis, arterial calcification, and chemotaxis, and it has anti‐inflammatory effects. Conversely, warfarin, a potent vitamin K inhibitor, has demonstrated adverse effects on bone remodeling and atherosclerosis. Natural forms of vitamin K are available in multiple dietary sources, and some structural forms are more readily available for use in metabolic pathways than are others. With regard to supplementation, the specific form of vitamin K is often not disclosed, and the recommended daily value is potentially less than what is physiologically required. On the basis of a review of the literature, it appears advantageous to encourage patients to eat a diet rich in vitamin K; however, the benefit of vitamin K supplementation alone is yet to be thoroughly conveyed.

Neurologic Outcomes After Low-Volume, Ultrasound-Guided Interscalene Block and Ambulatory Shoulder Surgery.

Background and Objectives Postoperative neurologic symptoms after interscalene block and shoulder surgery have been reported to be relatively frequent. Reports of such symptoms after ultrasound-guided block have been variable. We evaluated 300 patients for neurologic symptoms after low-volume, ultrasound-guided interscalene block and arthroscopic shoulder surgery. Methods Patients underwent ultrasound-guided interscalene block with 16 to 20 mL of 0.5% bupivacaine or a mix of 0.2% bupivacaine/1.2% mepivacaine solution, followed by propofol/ketamine sedation for ambulatory arthroscopic shoulder surgery. Patients were called at 10 days for evaluation of neurologic symptoms, and those with persistent symptoms were called again at 30 days, at which point neurologic evaluation was initiated. Details of patient demographics and block characteristics were collected to assess any association with persistent neurologic symptoms. Results Six of 300 patients reported symptoms at 10 days (2%), with one of these patients having persistent symptoms at 30 days (0.3%). This was significantly lower than rates of neurologic symptoms reported in preultrasound investigations with focused neurologic follow-up and similar to other studies performed in the ultrasound era. There was a modest correlation between the number of needle redirections during the block procedure and the presence of postoperative neurologic symptoms. Conclusions Ultrasound guidance of interscalene block with 16- to 20-mL volumes of local anesthetic solution results in a lower frequency of postoperative neurologic symptoms at 10 and 30 days as compared with investigations in the preultrasound period.

Poster 113: Association of Clinical Characteristics and Response to Lumbar Epidural Steroid Injections in Subjects with Axial Low Back Pain

Disclosures: Stephen Schaaf: I Have No Relevant Financial Relationships To Disclose Objective: Despite the frequency of interventional procedures performed for axial low back pain, selection criteria remain unclear and suboptimal to predict those that will have an improved outcome. The goal of the study was to examine the association of baseline clinical characteristics and pain improvement following lumbar epidural steroid injections (LESI) in individuals with axial low back pain. Design: Prospective Cohort Study Setting: Academic Medical Center. Participants: Subjects (n1⁄448) were eligible if they had primarily axial low back pain without radiating symptoms. Interventions: Patients recruited had already consented for and then underwent a LESI as part of their routine clinical care. Main Outcome Measures: Gender, age, body mass index, race, education, employment status, smoking status, Oswestry Disability Index, Roland Morris Disability, McGill Pain Questionnaire (MPQ), generalized anxiety disorder, Patient Health Questionnaire (PHQ-9), 10m-walking speed, fear avoidance beliefs questionnaire, catastrophizing, cumulative illness rating scale, prior treatments and exercise, treatment expectation, and medications were collected for baseline clinical characteristics. Pain was scored on 0-10 numeric rating scale. Pain score was taken at pre-injection and two-week follow-up. Responders to injection were defined as those who had at least a 50% reduction in their pain score at follow up. Results: At follow up, 17 subjects reported 50% or greater reduction in their pain score. Responders had a significantly lower PHQ total score, MPQ sensitive score, MPQ affective score, MPQ total score, more frequent exercise, and were less unsure about expecting pain relief following the LESI at baseline. No other significant associations were observed. Conclusions: Certain baseline clinical characteristics represent a potential opportunity to improve the clinical ability to predict response to treatment for LESI. A larger sample size with randomized study design to evaluate the ability of baseline clinical characteristics to improve clinical decision making will be needed. Level of Evidence: Level II

Lateral Antebrachial Cutaneous Nerve Entrapment After Shoulder Arthroscopy: A Case Report

The lateral antebrachial cutaneous nerve (LABCN) is a distal sensory branch of the musculocutaneous nerve that innervates the radial aspect of the forearm. Cases of LABCN injury from trauma and chronic compression have been reported. A case of musculocutaneous nerve injury after a biceps tenodesis has also been reported. This case report describes an LABCN injury and forearm pain after a biceps tenodesis procedure. Using a multifaceted diagnostic approach of electrodiagnostics and magnetic resonance neurography, the site of compression was appropriately localized. The patient ultimately achieved relief after a surgical decompression.

Poster 329 Complex Regional Pain Syndrome as a Result of Stingray Envenomation: A Case Report

provements with microsurgical techniques, patients need pain management to restore function. Intramedullary ependymomas typically occur in the cervical region; however, a thoracic ependymoma tends to have a higher morbidity. The neurologic morbidity depends on the preoperative functional status and perhaps early effective pain interventions. A majority of these patients will have proprioceptive dysfunction that also requires intensive physical therapy. This patient has the presence of an intradural neoplasm with a syrinx, which suggests a noninfiltrative lesion and a good prognosis, and may have benefitted from a pain program. Conclusions: Although many people do not develop central pain syndrome after ependymoma resection, to optimize functional outcomes for those who do, a comprehensive approach to pain will help maximize recovery.