Prakash Jayabalan

Heterotopic Ossification in Civilians With Lower Limb Amputations

OBJECTIVES To report the incidence of symptomatic heterotopic ossification (HO) in a defined civilian amputee population, describe its characteristics, and compare these findings to published data in military amputees. DESIGN Retrospective chart analysis from July 1998 to July 2009. SETTING Ambulatory amputee clinic within a large university medical center. PARTICIPANTS Adults with lower limb amputation (N=158). INTERVENTIONS Not applicable. MAIN OUTCOME MEASURE Patients with symptomatic HO confirmed by radiographs. RESULTS A total of 261 patients were evaluated; 158 met inclusion criteria, with 59% having traumatic etiology, 18% vascular etiology, 22% infection, and 1% tumor. Symptomatic HO was diagnosed in 36 (22.8%) patients, and 94% patients had mild HO on radiographic scoring. Rate of HO in amputations related to trauma was not increased compared with those of other etiologies. Surgical resection of the ectopic bone was required in 4 (11%) patients. CONCLUSIONS HO is seen commonly after civilian lower limb amputation regardless of etiology. The prevalence was less than that observed in previous reports from military populations. This is the first report estimating the prevalence of HO in adult civilian amputees.

The Kinetic Chain Revisited: New Concepts on Throwing Mechanics and Injury

The overhead throwing motion is a complex activity that is achieved through activation of the kinetic chain. The kinetic chain refers to the linkage of multiple segments of the body that allows for transfer of forces and motion. The lower extremities and core provide a base of support, generating energy that is transferred eventually through the throwing arm and hand, resulting in release of the ball. The kinetic chain requires optimal anatomy, physiology, and mechanics and is involved in all 6 phases of overhead throwing: windup, stride, arm cocking, acceleration, deceleration, and follow‐through. Breaks or deficits in the kinetic chain can lead to injury or decreased performance. Through an understanding of the mechanics and pathomechanics seen in each phase of throwing, the clinician can better evaluate and screen for potential kinetic chain deficits in the overhead throwing athlete. The purpose of this article is to review the biomechanics of the overhead throwing motion, the role of the kinetic chain in throwing, and the clinical evaluation and management of abnormal throwing mechanics and related injuries.

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.

Tanezumab in the treatment of chronic musculoskeletal conditions

ABSTRACT Introduction: The management of pain associated with chronic musculoskeletal conditions represents a significant challenge for the clinician. There remains a need for novel medications that have a significant analgesic benefit and are also safe and well tolerated. Both pre-clinical and clinical data have provided evidence of the role of nerve growth factor (NGF) in a multitude of pain eliciting conditions. Therefore, the development of monoclonal antibodies to NGF for chronic painful musculoskeletal conditions has generated interest. Areas covered: This manuscript is a review that examines both the pharmacological properties and clinical studies of tanezumab, the most widely studied antibody to NGF, for management of osteoarthritis (OA) and low back pain. In addition, the safety and tolerability profile and development history of tanezumab are also discussed. Expert opinion: Most studies provide strong support for the ability of tanezumab to provide clinically meaningful pain relief in individuals with these conditions, with longer-term studies suggesting durability of effect. The adverse event profile appears favorable, assuming the risk mitigation strategies are effective at reducing the incidence of joint-related side effects. Further data are being collected to define the optimal dose and dosing strategy in both OA and chronic low back pain.

The influence of continuous versus interval walking exercise on knee joint loading and pain in patients with knee osteoarthritis

OBJECTIVE To evaluate whether knee contact force and knee pain are different between continuous and interval walking exercise in patients with knee osteoarthritis (OA). METHODS Twenty seven patients with unilateral symptomatic knee OA completed two separate walking exercise sessions on a treadmill at 1.3m/s on two different days: 1) a continuous 45min walking exercise session, and 2) three 15min bouts of walking exercise separated by 1h rest periods for a total of 45min of exercise in an interval format. Estimated knee contact forces using the OpenSim software and knee pain were evaluated at baseline (1st minute of walking) and after every 15min between the continuous and interval walking conditions. RESULTS A significant increase from baseline was observed in peak knee contact force during the weight-acceptance phase of gait after 30 and 45min of walking, irrespective of the walking exercise condition. Additionally, whereas continuous walking resulted in an increase in knee pain, interval walking did not lead to increased knee pain. CONCLUSION Walking exercise durations of 30min or greater may lead to undesirable knee joint loading in patients with knee OA, while performing the same volume of exercise in multiple bouts as opposed to one continuous bout may be beneficial for limiting knee pain.

Poster 378: The Effect of Psychosocial and Socioeconomic Factors on Pain Experience in Patients Receiving Corticosteroid Injection in Knee Osteoarthritis

Disclosures: Julia Fram: I Have No Relevant Financial Relationships To Disclose Objective: To describe the prevalence of baseline shoulder pathology among elite wheelchair track athletes and explore acute changes following completion of an endurance event using self-report of pain, physical examination and sonographic evaluation. Design: Observational, cohort study. Setting: 2017 Chicago Marathon. Participants: 14 (7 male and 7 female) U.S. Paralympic wheelchair track athletes. Interventions: Not applicable. Main Outcome Measures: Visual analog scale (VAS) of pain, Wheelchair User’s Shoulder Pain Index (WUSPI), American Shoulder and Elbow Surgeons (ASES), and physical examination. Results: 8 subjects (57%) had experienced shoulder pain since use of a manual wheelchair. Baseline pain scores in non-dominant shoulders significantly correlated with age (r1⁄40.58, P 1⁄4 .03) and length of sport participation (r1⁄40.65, P 1⁄4 .012). Common ultrasound pathology included supraspinatus tendinosis, identified in four subjects, and osteoarthritis of the acromioclavicular joint, found bilaterally in 2 subjects at baseline. Post-competition screening was notable for unchanged pain scores and the development of tenderness to palpation of the biceps tendon in three cases, without sonographic evidence of acute changes to the biceps tendon. Conclusions: There is a notable prevalence of shoulder pain in elite wheelchair track athletes. Shoulder function is crucial to this population’s athletic performance and daily activities. An injury to the shoulder for these athletes does not only mean lost time in training for their sport, but it could potentially mean a loss of independence in their daily life. Describing acute changes in shoulder pathology following a high intensity endurance event is a first step to determining protocols for recovery post-race to help prevent long term shoulder issues for these athletes. Shoulder preservation is extremely important to the overall health and quality of life of these athletes. Level of Evidence: Level IV

Physical Activity and Worsening of Radiographic Findings in Persons With or at Higher Risk of Knee Osteoarthritis

The benefits of physical activity among persons with or at higher risk for knee osteoarthritis are well established. However, activity levels in this population are low, in part due to concern that activity will damage the knee joint. We hypothesized that sedentary and moderate‐vigorous physical activity are each associated with greater risk of radiographic worsening of knee OA.

Rehabilitation Strategies for the Athletic Individual with Early Knee Osteoarthritis.

Knee osteoarthritis (OA) is a major cause of disability in the United States. The condition has most commonly been associated with elderly sedentary individuals; however, it also can affect those who participate in regular athletic activities. The diagnosis and management of these individuals can be challenging because of both their higher level of physical activity and their overall athletic goals. Treatment requires an appropriate exercise regimen, rehabilitation program, and education of both the athlete and the coach. The focus of our article is to provide an up-to-date overview of the evaluation and management of the athletic individual who presents with symptomatic early knee OA, in particular, the nonsurgical rehabilitation treatment options available to the practitioner and the evidence to support these recommendations.

The Influence of Continuous Versus Interval Walking Exercise on Joint Loading and Serum Biomarker Profile in Patients with Knee Osteoarthritis

Disclosures: E. Kraus: I Have No Relevant Financial Relationships To Disclose. Objective: Bone stress injuries (BSIs) are a common overuse injury. The purpose of our study was to characterize the incidence and distribution of BSI in collegiate middle and long-distance runners at two NCAA Division I programs. Design: Male and female middle and long-distance runners were included in a retrospective chart review over three years (2010-2013). Data were obtained from physician visits and pre-participation evaluation screening. All running-related BSI were diagnosed by a physician and confirmed with x-ray and/or magnetic resonance imaging. Overall BSI incidence rate and incidence by person-years was determined and distribution stratified by age, sex, and skeletal site using mixed effects Poisson regression models. Setting: Stanford Hospital and Clinics, UCLA Medical Center. Results or Clinical Course: One hundred thirty three runners were evaluated (57 females, 76 males). The overall BSI incidence rate was 20% (35% for females, 10% for males). The overall BSI incidence per person-years was 0.25. 72% of females and 63% of males were at age nineteen or younger when they sustained their first BSI. The most common location for BSI was tibia (31.3%) followed by sacrum (16.4%), metatarsal (13.4%), femoral shaft (8.9%), femoral neck, navicular, fibula (each 7.4%), and other (8%). 37.7% of females sustained a BSI at a trabecular site (femoral neck, sacrum, calcaneus, manubrium). Conclusion: Twenty percent of collegiate distance runners sustained one or more BSI per year, with a higher incidence in females compared to males. Over half of males and females sustained BSIs at age nineteen or younger. The high percent of BSI at trabecular sites in female distance runners is concerning for inadequate nutrition and impaired bone health in this population and needs further study. These findings highlight the need for identifying risk factors for developing BSIs in collegiate runners with the ultimate goal of implementing management and prevention programs early in their collegiate training for widespread use by physicians, coaches and trainers. The authors would like to thank Sitaram Vangala, M.S., and David Elashoff, PhD for their help with the statistical analysis, and the UCLA Clinical Translational Science Institute and Research Laboratory (#UL1TR000124) for helping fund this study.

The Development of Gastroparesis in a Patient with Guillain-Barre Syndrome: A Case Report

Interventions: Not applicable. Main Outcome Measures: Recovery to grade IV or above at the point when patients require no more than supervision with the easiest self-care tasks (eating, grooming, and bowel and bladder management) but up to total assistance for the most demanding task (stair climbing). Results or Clinical Course: Physical grade IV was reached by 34% of those initially below it. Seven independent predictors were assigned the following points: age (<70 years1⁄42; 70-79 years1⁄41; >79 years1⁄40), time between initial and final grade assessment (1 to 2 days1⁄40; 3 to 7 days1⁄44; 8 or more days1⁄45), absence of renal failure1⁄41, no receipt of non-oral feeding1⁄43, admission physical grade (I1⁄40; II1⁄43; III1⁄44), admission cognitive stage (I or II1⁄40; III1⁄42; IV or V1⁄43; VI or VII1⁄44), and the type of rehabilitation services received (consultative1⁄40; comprehensive1⁄44). The proportions of patients recovered to physical grade IV in the 1st (score 9), 2nd (score1⁄410-12), 3rd (score1⁄413-15), and 4th (score>15) score quartiles were 2.72%, 11.38%, 28.96%, and 60.34%, respectively. The area under the receiver operating curve was 0.84 and 0.83 for the point system in the derivation and validation cohorts, respectively. Conclusions: Clinicians can forecast likelihood of recovery to or above the physical grade IV benchmark. At the first point when physical assistance with bowel and bladder management is no longer required, this benchmark represents a particularly meaningful recovery target.