Anterior Cervical Surgery For The Treatment Of Hirayama Disease

Objective: To assess the clinical and radiological outcomes of anterior cervical surgery for the treatment of Hirayama disease and to evaluate the clinical significance and value of this operation.Methods: A retrospective study was conducted on 19 patients who suffered from Hirayama disease received anterior cervical surgery between July 2008 and December 2015.All the patients were definitively diagnosed by the neurological specialists in our hospital after the motor neuron diseases excluded.After a least six months of conservative treatment,the disease was ineffective and progressed continuously.Among them,13 patients underwent anterior cervical fixation,while the other 6 patients received anterior cervical discectomy fusion.The clinical outcomes including tremor,cold paralysis,muscle strength and atrophy were recorded.The radiological outcomes including the cervical lordosis,the segmental and overall range of cervical flexed motion,angle mobility of C3/4 to C6/7 the cross-sectional area of spinal cord at C4-C7 level on MRI scan were measured before and last follow-up time.Results: All the patients were followed up for 33 to 122 months with an average of 72.5 ± 30.6 months.Tremor in 6 of 14 patients and cold paralysis in all 8 patients were resolved after operation.And 14 of the 19 patients showed improved muscle strength,however,no considerable improvement in muscle atrophy was noted in any of them.Compared measurements before operation with those at the latest follow up,the cervical lordosis [(2.70 ± 4.61)mm versus(6.41 ± 4.39)mm,P < 0.001] varied a statistical significance,the overall range of cervical flexed motion [(33.10±10.60)° versus(13.55± 6.69)°,P<0.001],and segmental range of C5/6 [(12.52± 7.13)° versus(7.04± 3.75)°,P<0.05],C6/7 [(9.01° ± 5.01)° versus(5.73 ± 2.74)°,P<0.05],statistically decreased.Postoperative angle mobility of C3/4 to C6/7 was significantly decreased(P < 0.001).At the last follow-up,the neutral magnetic resonance imaging revealed that the transverse area of spinal cord of C6(P<0.05)and C7(P<0.05)were significantly increased compared with that before surgery,and transverse area of spinal cord of C4 and C5 were not statistically significant(P>0.05).Conclusion: Anterior cervical surgery may provide clinical efficacy as well as imaging improvements.This operation has clinical significance and value in terms of control of the progression of this disease.