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Again, the most important aspect of image interpretation is to use a systematic and exhaustive approach. The old adage, “More lesions are missed from not looking than from not knowing,” is nowhere more true than in radiology. If possible, a quiet area with good quality view boxes should be set aside for radiographic interpretation; and distractions should be excluded. Similarly, a quiet room away from the bustle of the clinic should be used for performing ultrasound examinations. The effect of bias on interpretation in general practice, where the person evaluating the radiographs is also the attending clinician, is hard to avoid. It is important to be aware that the possibility of bias exists and attempt to exclude preconceived ideas about a particular case. When possible, seeking a second opinion from a colleague is valuable. Last, the observer should always ask, “What have I missed?” and review all findings before making a final decision. The skeleton is in many ways ideally suited to radiographic examination. Bone readily absorbs x-radiation, resulting in images with very good contrast. The skeleton is limited, however, in range of responses to an insult, either producing more bone, removing bone, or a mixture of both. Therefore, when evaluating skeletal structures, careful attention to fine detail is essential. Many diseases appear similar radiographically; but subtle differences and features, such as lesion distribution, nonskeletal lesions, and signalment, are helpful in refining a diagnosis. It is beneficial in musculoskeletal radiology to consider both generic changes and specific diseases. A useful analogy when exploring the radiographic diagnosis of skeletal disease is to think of osteoclasts and osteoblasts as demolition workers and builders and bone as the building site. Acute, active, and aggressive lesions—much like a building in the early stages of construction—appear quite untidy and disorganized. Chronic, inactive, and nonaggressive lesions appear well organized and orderly—like a finished building project. Radiographic Quality Radiographs can be obtained to evaluate the skeleton by different techniques, depending upon the personal preference of the reviewer. A technique using high kilovolt peak, kV(p), and low milliampere, mA, settings produces relatively gray images with limited inherent contrast, which can be tolerated as there is generally good contrast between bones and soft tissue. Bone structures appear well penetrated, and internal structures are clearly visible. A disadvantage is that soft tissues appear gray and dark. When using this kind of technique, it is essential to evaluate relatively dark areas of the image with a hot light.

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