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Background: Because of the unique theoretical surgical risks, including osteonecrosis, acute iatrogenic slipped capital femoral epiphysis, and epiphyseal injury, the optimal treatment strategy for femoroacetabular impingement (FAI) in growing adolescents has yet to be established. The aim of this study was to compare the clinical outcomes of primary arthroscopic treatment of FAI in growing adolescents with a matched adult group.Methods: Patients with FAI who underwent arthroscopic treatment with a minimum follow-up of 2 years were included.Patients with previous ipsilateral hip surgery, an Outerbridge grade of ‡3, a preoperative Tönnis grade of ‡2, or evidence of dysplasia (lateral center-edge angle of <25°) were excluded. Eligible patients who were £19 years old and whose proximal femoral physis had not yet closed were matched to adult (20 to 40-year-old) counterparts in a 1:1 ratio by sex, body mass index, and time of surgery. For the adolescents, cam resection was performed with a physeal-sparing approach. Outcome scores, including the modified Harris hip score (mHHS), Hip Outcome Score-Activities of Daily Living (HOS-ADL), and HOS-Sports-Specific Subscale (HOS-SSS), were prospectively collected.Results: Of the 196 eligible adolescents, 157 (80%) were pair-matched to adult controls, with a median postoperative follow-up of 8.9 and 6.6 years, respectively. Fourteen (9%) of the adolescents required revision hip arthroscopy compared with 18 adults (11%) (p = 0.46). No patient in the adolescent group had conversion to a total hip arthroplasty (THA), while 3 in the adult group had a THA (p = 0.25). For adolescents without subsequent hip surgery, the median mHHS improved from 59 preoperatively to 96 postoperatively; the HOS-ADL, from 71 to 98; and the HOS-SSS, from 44 to 94 (p < 0.001), which were significantly higher postoperative scores than those of the matched adults (p < 0.05) despite similar or inferior baseline scores. No complications were found during the office visit or at the final follow-up.Conclusions: Hip arthroscopy performed with a physeal-sparing approach for FAI in growing adolescents is safe and effective and yields superior clinical outcomes compared with those in a matched adult group.Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.F emoroacetabular impingement (FAI) is characterized by abnormal contact between the femur and acetabulum because of anomalous osseous pathology occurring at the femoral head-neck junction or acetabular rim 1,2 , which can damage the intra-articular structures of the hip and eventually lead to osteoarthritis 3 . FAI has been shown to develop during the accelerated growth phase of development [4][5][6][7][8] . A cam deformity can be more likely to develop when adolescents with open physes engage in sports that require repetitive high impact loading, hip flexion, and internal rotation (e.g., ice hockey, basketball, and soccer) 9,10 . Wyles et al. 11 found that cam deformities and limited hip range ...

As a profession, historical records administration has grown significantly in the past two decades. The growing size of the profession has precipitated a demand for better archival education and training programs. The session addressed the recently approved SAA guidelines for archival education programs and the prospects for the certification of archivists, the accreditation of archival programs, and the function of short term archival institutes. TRUDY H. PETERSON:The men and women who organized our profession some forty years ago gave us many things: a literature, an ethos, a sense of community, and an ever widening recognition of professional fundamentals. Yet these founders never clearly defined the role of the archivist nor what skills were needed to be an archivist. Those who worried about definitions were at pains to distinguish the archivist from the librarian, the curator, the records manager, and the academic historian. And although the need for archival education was recognized immediately, archival principles and techniques were taught in a wide variety of settings, from Ernst Posner's famous American University courses to institutes, short courses, workshops, and various types of in-house training.With a profession that has grown in size and vigor over the past forty years without a standard for archival education, why then should we adopt one? The answer is that the profession has two fundamental responsibilities that it cannot adequately meet so long as the current anarchic situation continues. The first is the responsibility to protect the general public from incompetent or unscrupulous practitioners. The profession has an obligation to regulate itself-to assure that a person formally designated as an archivist meets certain specified standards agreed upon by the profession, and that archival training programs provide certain fundamental information and experience and maintain conditions under which the achievement of basic professional knowledge can be reasonably expected. The second responsibility is to assist members of the profession in securing employment commensurate with professional status. Assurance of employment equity for the profession seems, at first glance, a selfish and mercenary reason to tinker with the current status of archival training. But its importance stems from a singular fact about archives: they are almost universally part of a larger bureaucracy. Most archivists have had neither specialized diplomas nor adequate equivalents of such, and so have faced the bureaucracy empty-handed. While by no means a complete solution, a standardization of archival training could help us meet these responsibilities.A program of institutional and personal archival certification is the logical first step. Two types of archival education could be certified. Type A would include courses and practicums given for academic credit as part of a program of academic

Laser-based remote sensing is undergoing a remarkable advance due to novel technologies developed at MIT Lincoln Laboratory. We have conducted recent experiments that have demonstrated the utility of detecting and imaging low-density aerosol clouds. The Mobile Active Imaging LIDAR (MAIL) system uses a Lincoln Laboratory-developed microchip laser to transmit short pulses at 14-16 kHz Pulse Repetition Frequency (PRF), and a Lincoln Laboratory-developed 32x32 Geiger-mode Avalanche-Photodiode Detector (GmAPD) array for singlephoton counting and ranging. The microchip laser is a frequency-doubled passively Q-Switched Nd:YAG laser providing an average transmitted power of less than 64 milli-Watts. When the avalanche photo-diodes are operated in the Geiger-mode, they are reverse-biased above the breakdown voltage for a time that corresponds to the effective range-gate or range-window of interest. The time-of-flight, and therefore range, is determined from the measured laser transmit time and the digital time value from each pixel. The optical intensity of the received pulse is not measured because the GmAPD is saturated by the electron avalanche. Instead, the reflectivity of the scene, or relative density of aerosols in this case, is determined from the temporally and/or spatially analyzed detection statistics.There are several advantages to sensor architectures that use direct detection and arrays of photon-counting detectors. Perhaps the most significant advantage is a reduced requirement for power-aperture product of more than an order of magnitude. In this paper, we describe the LIDAR sensor system used in MAIL, and our experimental results showing system sensitivity, and temporal and spatially resolved releases of aerosol clouds within a controlled chamber.