Computed tomographic method for measurement of inclination angles and motion of the sacroiliac joints in German Shepherd Dogs and Greyhounds

Abstract

The small amounts of sacroiliac joint motion detected in this study may buffer high-frequency vibrations during movement of dogs. Differences detected between breeds may be associated with the predisposition of German Shepherd Dogs to develop lumbosacral region signs of pain, although the biological importance of this finding was not determined. Future studies are warranted to compare sacroiliac joint variables between German Shepherd Dogs with and without lumbosacral region signs of pain.

Influence of Radiographic Positioning on Canine Sacroiliac and Lumbosacral Angle Measurements

“…Canine sacroiliac and lumbosacral inclination angles measured on radiographs can potentially be used to correlate joint angulation with degenerative changes of the lumbosacral joint, stifle or tarsal joints. [1][2][3][4][5] The sacroiliac joints are paired synovial and cartilaginous joints separating the wings of the sacrum and ilium that are part of the weight-bearing axis of the pelvic limb and function to transmit forces during locomotion. 3,[6][7][8] In dogs, the sacroiliac joints have crescent-shaped articular surfaces, irregular interlocking projections, depressions and fibrocartilage with sacroiliac ligaments creating increased stability.…”

“…8 The function of the sacroiliac joint requires both rigidity for transmitting forces and flexibility to act as a buffer to motion. 3 Forces transmitted through the sacroiliac joint travel through the coxofemoral joint, acetabulum, ilium, sacrum and lumbar vertebrae. Loads applied to the sacroiliac joint are therefore considered similar to loads applied to the hip joint.…”

“…2,6,7,9 Sacroiliac joint instability and pain can result from intense or repetitive activities. 3,5,9 Continued abnormal motion may then lead to degenerative changes including spondylosis and osteophyte formation, which can reduce overall range of motion and result in clinical problems associated with the compression of neural structures. 1,4 Degenerative changes in sacroiliac joints could also affect the lumbosacral and hip joints due to altered loading of the sacroiliac joints.…”

“…1,4 Degenerative changes in sacroiliac joints could also affect the lumbosacral and hip joints due to altered loading of the sacroiliac joints. 3,10 The inclination angles of the sacroiliac and lumbosacral joints can affect the transmission of forces through joints, which may therefore determine the loading capacity of the joint. 3,9 In dogs, it is not known how changes in sacroiliac joint angles influence hindlimb joint angles or progression of orthopaedic conditions affecting these joints.…”

“…3,10 The inclination angles of the sacroiliac and lumbosacral joints can affect the transmission of forces through joints, which may therefore determine the loading capacity of the joint. 3,9 In dogs, it is not known how changes in sacroiliac joint angles influence hindlimb joint angles or progression of orthopaedic conditions affecting these joints. Measurements of motion of the sacroiliac joint have been performed using several different methods ranging from radiographic studies of dissected pelves (median range of motion, 7°) to tomographic studies of anaesthetized purebred dogs (mean AE SD range of motion, 2.0 AE 1.5°for German shepherd dogs and 1.5 AE 0.7°f or Greyhounds).…”