RESUMO
BACKGROUND: In general, atlantoaxial dislocation is rare due to the stability of the C1-C2 complex. Traumatic atlantoaxial dislocations are usually anterior and accompanied by odontoid fractures. Posterior atlantoaxial dislocations are rare, and complete posterior dislocation without associated fracture is even more rare. A case of early recurrence of posterior atlantoaxial dislocation without fracture being in therapy of first closed reduction and then open reduction has not been previously reported. CASE SUMMARY: A 45-year-old female presented with traumatic posterior atlantoaxial dislocation (TPAD) of C1-C2 without associated fractures, and Frankel Grade B spinal cord function. She was successfully managed by immediate closed reduction under skull traction. Unexpectedly, 17 d later, re-dislocation was discovered. On day 28, closed reduction was performed as before but failed. Then, open reduction and posterior internal fixation with autologous iliac bone grafts was performed. By 6 mo after surgery, atlantoaxial joint fusion was achieved, and neurological function had recovered to Frankel Grade E. At 12 mo follow-up, she had lost only 15° of cervical rotation, and atlantoaxial complex instability in joint flexing and extending were no longer observed under fluoroscopy. CONCLUSION: Early assessment of transverse ligament is critical for TPAD without fracture avoiding re-dislocation after closed reduction.
RESUMO
Nearly all previous studies in posterior tibial slope (PTS) and anterior cruciate ligament (ACL) injuries ignored age-related changes, and the published data are inconsistent. The objective of this study was to reveal age-related changes of PTS and its roles in ACL injury. Data for 2618 lower limbs were included initially based on the availability of lateral radiographs and a suitable femoro-tibial angle. The final 1431 subjects were analyzed according to age, gender, side, and injury status. Student's t-tests, one-way analysis of variance, and curve fitting were used to analyze data. The PTS in males was greater than that in females in the 0-9 and 30-39-year-old groups, but this pattern reversed in the 40-49, 60-69, 70-79, and 80-89-year-old groups. The PTS was greater on the left side than on the right side in the 0-9, 10-19, 50-59, 60-69, and 80-89-year-old groups. The curve fitting for PTS demonstrated a trend of first decreasing and then increasing with aging. The PTS values differed significantly between knees with an ACL injury and those without in the 20-29, 30-39, and 40-49-year-old groups but not in the 50-59-year-old group. The PTS follows a trend of first decreasing and then increasing, and its role in ACL injury changes with advancing age. The higher PTS is only unrelated to the risk of ACL injury in age groups with a lower mean PTS value.
