The Application Of Intercostal Nerve Transfer In Obstetric Brachial Plexus Palsy

Objective To study the therapeutic effect of intercostal nerve transfer for restoration of elbow flextion in infants with obstetric brachial plexus palsy.And to assessment the pulmonary function of the children after transfer of the intercostal nerve.Methods Between December 2001 and July 2008,a total of fifty-seven patients with obstetric brachial plexus palsy(OBPP) underwent intercostal nerve(ICN) transfer.The mean patient age at surgery was 6.8 months and mean follow-up period was 2.0 years.33 cases of them were randomly selected to take an examination of pulmonary function(operation group),the mean age was 33.1 months.A control group with 31 patients related to OBPP took the pulmonary function examination at mean 32.9 months.All of the control group have never underwent the nerve transfer of intercostal nerve or phrenic nerve.The function of elbow flexion was evaluated in all cases,which include muscle power and appearance time of elbow flexion.Muscle power was assessed using Kawabata improved British Research Council Muscle Movement Scale grades of M0 to M4.Grade M0 signifies no contraction and M1 a trace of contraction.Grade M2 is used to indicate active flexion more than 90°with gravity eliminated and Grade M3 active flexion more than 90°against gravity.Grade M4 was recorded when there was active movement against gravity and resistance.Appearance time of elbow flexion was indicated by the first time when we observed the elbow flexion(＞M1) after operation. Pulmonary functional parameters including vital capacity max(VCMAX), forced expiratory volume in one second(FEV1),forced expiratory flow 25-75(FEF25-75),airway resistance Rrs5(R5),reactance Xrs5(X5),tidal volume(VT/kg),time taken to reach peak expiratory flow to total expiratory time(TPTEF/TE),volume taken to reach peak expiratory flow to total expiratory volume(VPEF/VE).Those who could collaborate with the examination,checked VCMAX,FEV1,FEF25-27 when they were elder than 4.5 years and the others checked R5 and X5.TPTEF/TE and VPEF/VE were examed in the patients who could not collaborate with the test.We observed daily clinical syndrome in operation group.Results There were 24 patients followed up more than 2.0 years.Fourteen patients were used 4 ICNs,four of them gained biceps muscle power to the level of Grade M4,six patients exhibited Grade M3 and three Grade M2.Mean follow-up period of the 14 patients was 32.3 years.There were 9 patients using 3 ICNs,followed up by 45.6 months.Eight of them gained biceps muscle power to the level of Grade M4 and one Grade M3.We performed 4 ICNs transfer to musculocutaneous nerve(MCN) in four patients and three of them reached M4.There were two patients gained M4 in 10 children who underwent 4 ICNs transfer to the anterior division of the upper trunk(AUT).We observed 54/57 patients gained active elbow flexion at average 7.8 months after surgery.Twelve of them were used 3 ICNs,whose elbow flexion were found out at mean 7.0 months.We transferred 3 ICNs to MCN in seven patients at average 6.6 months old.Mean 7.0 months later,active elbow flexion were observed.Four ICNs were used in 40 patients,their elbow flexion were discovred 7.4 months after surgery.We transferred 4ICNs to MCN in 24 infants at average 10.5 months old.After mean 6.3 months,we observed active elbow flexion.The other 16 patients whose 4 ICNs were transferred to AUT flexed their elbow at average 9.1 months after surgery.In operation group 4 of 33 were examed VCMAX,FEV1,FEF25-27 and 3 of all were checked R5 and X5.We checked TPTEF/TE and VPEF/VE in other 26 patients.In control group 2 of 31 were examed VCMAX,FEV1,FEF25-27 and 2 of all were checked R5 and X5.We checked TPTEF/TE and VPEF/VE in other 27 patients.There were 17 patients in operation group and 17 patients in control group,whose pulmonary fuction were abnormal.The difference are of no statistical significance(X~2test,X~2=0.07&0.13,p＞0.05).All the patients in operation group appeared to have no difficulties in daily living.Conclusions Transfer of intercostal nerve for restoration of elbow flextion in infants with obstetric brachial plexus palsy presented excellent results and did no harm to the pulmonary function of the patients. We should approach the anastomotic stoma to biceps brachii to improve the effect.Using 3 ICNs or 4 ICNs made the result no difference,but if the age of the patient was old,we recommended using more ICNs to gain the better effect.