Patellar tendon reflex as a predictor of improving motor paralysis in complete paralysis due to cervical cord injury.

STUDY DESIGN: A retrospective study. OBJECTIVE: We have encountered several cases of complete sensorimotor paralysis in which patellar tendon reflex (PTR) was demonstrated approximately 3 days after injury and improvement of motor paralysis was subsequently achieved. We considered that PTR apparent in the early stage after injury may offer an index to predict improvements in motor paralysis. MATERIALS AND METHODS: A total of 142 patients assessed as ASIA Impairment Scale A on admission from 1979 to 1998 were included in the study. The patients who demonstrated PTR within 72 h after injury were classified as the PTR(+) group and those who did not constituted the PTR(-) group. With regard to the method of motor paralysis assessment at about 6 months after injury, patients assessed as ASIA Impairment Scale A or B (that is, complete motor paralysis) were classified as 'Non-recovered', whereas those assessed as ASIA Impairment Scale C, D or E (that is, showing obvious improvement of motor paralysis) were considered as 'Recovered'. RESULTS: A significant difference was noted between groups, with the Recovered group including 16 of the 17 PTR(+) patients (94.1%) and 11 of the 115 PTR(-) patients (9.6%) (P<0.0001). CONCLUSION: The results obtained indicate that motor paralysis recovery could be expected at a very high rate among patients demonstrating PTR within 72 h of injury. As all physicians should be familiar with the PTR, this seems to represent a simple and highly useful sign to predict improvements in motor paralysis during the acute stage of cervical cord injury.