There are millions of orthopedic surgeries and dental implantation procedures performed every year globally. Most of them involve machining of bones and cartilage. However, theoretical and analytical study on bone machining is lagging behind its practice and implementation. This study views bone machining as a machining process with bovine bone as the workpiece material. Turning process which makes the basis of the actually used drilling process was experimented. The focus is on evaluating the effects of three machining parameters, that is, cutting speed, feed, and depth of cut, to machining responses, that is, cutting forces and surface roughness resulted by the turning process. Response surface methodology was used to quantify the relation between the machining parameters and the machining responses. The turning process was done at various cutting speeds (29-156 m/min), depths of cut (0.03 -0.37 mm), and feeds (0.023-0.11 mm/rev). Empirical models of the resulted cutting force and surface roughness as the functions of cutting speed, depth of cut, and feed were developed. Observation using the developed empirical models found that within the range of machining parameters evaluated, the most influential machining parameter to the cutting force is depth of cut, followed by feed and cutting speed. The lowest cutting force was obtained at the lowest cutting speed, lowest depth of cut, and highest feed setting. For surface roughness, feed is the most significant machining condition, followed by cutting speed, and with depth of cut showed no effect. The finest surface finish was obtained at the lowest cutting speed and feed setting.
Radial tunnel syndrome refers to pain on the lateral aspect of the forearm as a result of compression of the posterior interosseous nerve within a tunnel with specific anatomical boundaries. Diagnosis of the condition is difficult because of its close association with lateral epicondylitis, which warrants different methods of treatment. Based on a cadaveric study, a new clinical test, the Rule-of-Nine test, is proposed to improve the diagnostic accuracy in radial tunnel syndrome. The test involves constructing 9 equal squares on the anterior aspect of the forearm and noting those squares where tenderness can be elicited.
Orthopaedic procedures especially dynamic hip screw (DHS) fixation, interlocking nailing (ILN) of the tibia and femur require fluoroscopic assistance. Frequent exposure to radiation is a major concern to members of the orthopaedic surgical team. This study was undertaken to measure shallow (skin) dose to the operating team personnel and deep (whole body) dose to the surgeon during such procedures in view to provide guidelines to the operating team members regarding the number of procedures allowable for them to perform or assist annually. Skin dose for the operating personnel and whole body dose for the operating surgeon during 25 procedures; ten cases of DHS, seven and six cases of ILN of the tibia and femur respectively, was measured using Thermoluminescent Dosimeter (TLD) chips. The shallow radiation dose for theatre personnel ranged from 0.19 mSy to 0.61 per case while the deep dose for the surgeon was 0.28, 0.55 and 0.81 mSy for seven cases of tibial ILN, ten cases of DHS and six cases of femur ILN respectively. The surgeon has the highest radiation exposure than other theatre personnel and the whole body exposure for DHS was higher than that of for ILN. However, the estimated cumulative dose was still far below the permissible annual dose limit.
Cervical spondylotic myelopathy (CSM) represents a spectrum of pathologies with progressive compression of the spinal cord. The clinical signs and symptoms play a key role in diagnosis. The characteristic hand myelopathy signs are of significant clinical importance. The aim of this descriptive study was to report a relatively easy to elicit new hand myelopathy sign. The basis for this is finger and wrist flexor disinhibition, which is used for the spinal specificity of cord compression at or above the C5/6 level.