Review of Exploration Systems Development (ESD) Integrated Hazard Development Process

The Chief Engineer of the Exploration Systems Development (ESD) Office requested that the NASA Engineering and Safety Center (NESC) perform an independent assessment of the ESD's integrated hazard development process. The focus of the assessment was to review the integrated hazard analysis (IHA) process and identify any gaps/improvements in the process (e.g. missed causes, cause tree completeness, missed hazards). This document contains the outcome of the NESC assessment

PLOSONEcomplete data set. (TPLO alignment jig-saw guide)

Raw data collected for two groups of clinically performed TPLOs (a crescent osteotomy of the proximal tibia designed to alter the craniotibial shear force as a result of a cranial cruciate deficient knee). Group 1 (2005-2007): freehand osteotomies with jig only; Group 2 (2013-2015): freehand osteotomies with jig only. Group 1 follows recommendation at that time to place proximal jig pin through center of medial collateral ligament (MCL). Group 2 follows the later recommendation to place the jig pin behind the MCL. The objective of the study is to determine if a saw guide attached to the jig can match the positions of the osteotomy performed by experienced surgeons, and also is it can replicate the ideal osteotomy location. The data file are all measurements obtained from these clinical cases that compares guide-to-osteotomy fit and the appropriateness of the osteotomy based upon current published guidelines. All methods are described in the manuscript

Short-Term Clinical and Radiographical Outcome after Application of Anchored Intervertebral Spacers in Dogs with Disc-Associated Cervical Spondylomyelopathy

Objectives The purpose of this study was to assess the short-term outcome of a new intervertebral anchored fusion device (C-LOX) for the treatment of disc associated cervical spondylomyelopathy (DA-CSM) in dogs, based on clinical and radiographical follow-up data. Materials and Methods To be included in the study, dogs had to be clinically affected by DA-CSM treated with surgical distraction/stabilization using the anchored intervertebral spacer (C-LOX). Neurological signs, as well as diagnostic imaging performed pre-, immediately postoperatively, and after 6 weeks and 3 months were assessed. If available, clinical follow-up after 3 months was documented. Results Thirty-seven cases were enrolled in the study. Outcome at 3 months was available in 25 dogs; improvement of neurological status was documented in 25/25 cases. The most common postoperative complication was screw loosening and/or breakage (n = 22), followed by subsidence (n = 15). Four dogs required revision surgery. Clinical Significance Distraction/stabilization of DA-CSM in dogs with the C-LOX device resulted in short-term clinical improvement in 33/37 treated cases. The high incidence of screw loosening was taken into consideration and modification of the implant with a new locking system and new screw dimensions was required. The C-LOX device seems to be a valuable alternative to more complicated distraction–fusion techniques

Novel TPLO Alignment Jig/Saw Guide Reproduces Freehand and Ideal Osteotomy Positions

<div><p>Objectives</p><p>To evaluate the ability of an alignment jig/saw guide to reproduce appropriate osteotomy positions in the tibial plateau leveling osteotomy (TPLO) in the dog.</p><p>Methods</p><p>Lateral radiographs of 65 clinical TPLO procedures using an alignment jig and freehand osteotomy performed by experienced TPLO surgeons using a 24 mm radial saw blade between Dec 2005–Dec 2007 and Nov 2013–Nov 2015 were reviewed. The freehand osteotomy position was compared to potential osteotomy positions using the alignment jig/saw guide. The proximal and distal jig pin holes on postoperative radiographs were used to align the jig to the bone; saw guide position was selected to most closely match the osteotomy performed. The guide-to-osteotomy fit was categorized by the distance between the actual osteotomy and proposed saw guide osteotomy at its greatest offset (≤1 mm = excellent; ≤2 mm = good; ≤3 mm = satisfactory; >3 mm = poor).</p><p>Results</p><p>Sixty-four of 65 TPLO osteotomies could be matched satisfactorily by the saw guide. Proximal jig pin placement 3–4 mm from the joint surface and pin location in a craniocaudal plane on the proximal tibia were significantly associated with the guide-to-osteotomy fit (<i>P</i> = 0.021 and <i>P</i> = 0.047, respectively).</p><p>Clinical Significance</p><p>The alignment jig/saw guide can be used to reproduce appropriate freehand osteotomy position for TPLO. Furthermore, an ideal osteotomy position centered on the tibial intercondylar tubercles also is possible. Accurate placement of the proximal jig pin is a crucial step for correct positioning of the saw guide in either instance.</p></div

The distribution of frequency for each saw guide position as the best guide-to-osteotomy fit for freehand osteotomies based on group.

<p>The distribution of frequency for each saw guide position as the best guide-to-osteotomy fit for freehand osteotomies based on group.</p

Depiction of the osteotomy options available with each of the twelve positions and ±30° from a baseline of 90° angulation of the proximal jig arm.

<p>Each shaded area is a result of angulating the jig arms in each of the positions selected (ABC/1234).</p