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Obstetric brachial palsy following breech delivery is a typical group: upper lesions predominating with a great number of upper root avulsions and phrenic nerve lesions. In some cases spontaneous nerve recovery is insufficient and further treatment is considered in the first months of the infant's life. The results of surgical treatment of 61 cases of upper brachial plexus lesions after vaginal breech delivery who did not recover sufficiently are reported. In this group the following nerve transfers were applied: 51 accessory, 28 medial pectoral, 2 hypoglossal nerve transfers, and in 2 cases transfer of intercostals; in some cases the transfers were part of an extended brachial plexus reconstruction. Generally, the results of both primary and possibly secondary operations in this series were rewarding: 53% good and 20% fair. In both these groups most patients are able to position and use their more or less normal hand such that they can function normally, without serious impairment according to the international classification.
In the past 25 years we have treated more than 1000 patients with birth-related brachial plexus palsy, of whom about 40% needed primary surgery. During follow-up at a later date some of these patients also required secondary surgery; some of the patients who had not needed primary nerve surgery also underwent secondary surgery later. The incidence of this injury in the present series does not differ significantly from other reported figures, but because of the current obstetric approach in The Netherlands the number of vaginal breech deliveries in our series is high. Thus, it would seem to be of interest to report on this injury in particular.
Up to January 2000 we had treated 62 patients who had undergone primary surgery in whom the palsy occurred after breech delivery; one of these followed cesarean section delivery of a breech presentation. Breech delivery is complicated. Brachial plexus lesions occur at a higher rate than in patients who are born after vertex presentation. In 62 patients, primary (nerve) surgery was performed. Although bilateral brachial plexus palsy had occurred in 14 patients (22%), bilateral primary surgery was necessary in only 2 of these. Thus, we performed primary surgery in 62 patients, in 2 cases bilaterally (=total of 64 sides) (see also Table Table1).1). We report the results of surgical treatment of 61 cases of upper brachial plexus lesions; three complete lesions were not included because of the small number, and in the latter cases the results of gain in hand function have until now been disappointing. In one child the follow-up period was just over 2 years and distal results could not yet be evaluated as recovery of hand function can take many years to develop.
The birth weight of the neonates in this series (see Table Table1)1) contrasts with that of our cases of brachial plexus palsy after vertex presentation,1 the latter cases being almost invariably macrosomic neonates.
In all children, a functional disturbance of the arm was noted directly after birth, although in some the cause was initially suspected to be a fracture. In fact, a local hematoma pointed to the site of the trauma in nine cases (14%). In seven cases the clavicle was fractured (11%), in three cases the humerus (4%), and one child had a fracture of the femur.
In 95% of the cases (n=61) there was paralysis of the upper roots only, in 44 cases (68%) of C5 and C6, and in 17 (27%) of C5, C6, and C7. In these babies the arm is internally rotated and pronated, and there is no active abduction or elbow flexion. If C7 is also damaged (the extensor muscles are paralyzed) the elbow may lie slightly flexed and waiter's tip position of the hand is pronounced.2 In 15 of these babies hemiphrenic nerve palsy was present (see later). Pectoralis major, finger, and thumb flexors are usually active, but muscle atrophy often develops early (Fig. 1). Fourteen babies had bilateral lesions (phrenic nerve lesion and especially bilateral lesions are typical in breech) (Fig. 2). Distal sensation and vasomotor control are usually unaffected. An almost complete palsy of upper and lower roots was present in only three cases. Horner's sign was present; their phrenic nerve was normal.
In one of these (which followed cesarean section delivery of a breech presentation), isolated early recovery of suprascapular function had occurred.
Phrenic hemiparalysis was present in 15 neonates (26%). Most pediatric surgeons consider surgical treatment (plication of the diaphragm) to be necessary only in neonates who have respiratory difficulties. This proved to be the case in seven patients, and in six plication was performed before brachial plexus surgery. One patient, who was refused plication before plexus surgery, developed serious respiratory difficulties directly after the operation. We assumed this was due to the impact of prolonged surgery and to being immobilized in a cast. We are convinced that the indication for plication must not be too strict. In some children hemiphrenic plication may later prove to be a disadvantage; during thoracotomy required for plication, section of the latissimus dorsi may render this muscle unsuitable for later latissimus dorsi transfer. Currently, the indication for phrenic plication has been widened because of the less invasive endoscopic technique now available. The added advantage is that no harm is done to the latissimus dorsi muscle.
Radiological involvement of cervical dural sac and root sleeves was frequent in this series. A myelogram showing normal roots and root sleeves was found in only six patients. In one patient we refrained from myelography because of the child's clinical condition. Thus, the myelogram was abnormal in 54 patients. Traumatic arachnoid cysts (meningoceles), derived from torn root sleeves, often bilateral, almost seemed to be the rule in obstetric brachial plexus lesions following breech delivery. Rarely the cyst reached outside the foraminal canal. In most cases arachnoid cysts were present on the upper roots only. Although myelography was performed in all but one case, the results in our early cases did not allow us to decide on the presence or absence of intradural rootlets. The improvement in the quality of computed tomography–myelography allows a more reliable assessment.
The interpretation of the neurophysiological findings in neonates with brachial plexus lesions is different from that in adults, possibly because of anatomical differences (Vredeveld et al3). As mentioned previously, brachial plexus lesions following breech delivery include a significant proportion of intradural root lesions, whether total or partial avulsions. In adult cases the presence or absence of sensory nerve action potentials (SNAPs) differentiates between root lesions and extraforaminal lesions. In neonates, SNAPs are often difficult to measure because of the small size of fingers and hands and lack of cooperation. Also, they require the use of special electrodes.
If biceps function had not returned by the age of 3 months, we followed Gilbert and Tassin's4 criterion to operate supplemented by Clarke's criteria.5 Gilbert concluded that if babies had not developed normal deltoid or biceps function by the age of 3 months, they could not expect a good outcome, and thus considered this to be the indication for surgical intervention. Another indication was evidence of a severe lesion, such as Horner's syndrome, persisting hypotonic paralysis, persisting hemiphrenic paralysis, or severe sensory disturbances. Terzis and Papakonstantinou6 recommend surgery to take place, earlier than 3 months for global palsy cases and at 3 months for upper (Erb's type) lesions, for best functional results. The neurophysiological and radiological findings may add to the indication to operate, but the decision is mostly made on clinical grounds because the radiological findings are sometimes difficult to interpret and neurophysiological changes may present a rosier picture than justified by the patient's final result.2,5,7,8
Most patients were operated before reaching 6 months of age (Table 1). Fourteen patients were older than 6 months at the time of operation. In two patients who underwent bilateral surgery, the second operation was performed within 1 month of the first, well before the age of 6 months.
The surgical findings were grouped as shown in Table Table2.2. We scored definite avulsion when there were one or several exteriorized root ganglia. In the extreme case the ganglion was without any contact with the foramen, but sometimes the motor and sensory roots had some anatomical connection with the foramen although the ganglion was clearly visible. When we found one or several soft pale roots that could be traced up to the foramen, without a neuroma and without presentation of the ganglion, and which did not respond to stimulation, we scored probable avulsion (avulsion in situ), especially when this was supported by the radiological findings. When we found a neuroma and in particular when the roots responded to stimulation we scored no avulsion; in eight patients there was no avulsion of any root. In eight other patients we found definite or probable avulsion of one or more roots in combination with a neuroma of another root or trunk (Fig. 3).
Table Table33 shows the types of primary interventions. It is obvious that more than one type of intervention was often performed in one patient. Intraplexal reconstructions required resection of the neuroma and interposition by free nerve transplants.
Accessory nerve transfer was performed in 51 surgical cases, mainly to the suprascapular nerve (n=46). In four cases the nerve was connected to the site of entry of the spinal nerve C6 to the upper trunk, and in one case of complete avulsion of C6 the accessory nerve was connected to its motor root and sensory nerves from the cervical plexus to its sensory root. Accessory nerve transfer to the suprascapular nerve was combined with transfer of medial pectoral nerves to the musculocutaneous nerve in 20 cases, in one patient motor nerves from the cervical plexus were added to the neurotization, and in one pectoral nerves were also sutured to the axillary nerve. In one patient a secondary nerve operation was performed requiring the suture of intercostal nerves to the musculocutaneous nerve because of failure of the primary transfer to the musculocutaneous nerve. Also, pectoral nerves were used especially for neurotizing the musculocutaneous nerve.9 The hypoglossal nerve was used to neurotize the anterior division of the upper trunk twice to obtain elbow flexion and enhance median nerve function.10 Intercostal nerve transfer was performed twice as mentioned previously, in one case as a secondary procedure. We have added transfer of the cutaneous branch of the musculocutaneous nerve as a means of neurotizing the brachioradialis muscle in one patient, who had undergone a pectoral-musculocutaneous transfer, and this was found to be successful at follow-up.
When a root was regarded as a probable avulsion, our usual attitude was to leave the root in place, to allow spontaneous recovery to occur, because of the possible presence of partial avulsion. In these instances we still often performed nerve transfers for shoulder control and elbow flexion at the time of the first exploration. Gilbert4 found some kind of spontaneous recovery in 50% of the cases with probable avulsion following breech delivery, ranging from recovery of one muscle to full recovery, supporting the presence of partial avulsion in these cases. If recovery did not take place, he performed a secondary intraplexal neurotization after 1 year.
Table Table44 depicts the number and type of secondary surgical procedures. In many patients, secondary surgery was not necessary because a good result was achieved; in others more than one procedure was performed successively. Although subscapular lengthening and shortening of the coracoid were noted in this table, these procedures are not strictly speaking secondary interventions. Also, re-Steindler should be omitted for similar reasons, so that in fact 18 secondary surgical interventions were performed in 11 patients, and in 48 patients no secondary operations as such were necessary. Secondary surgery was mainly performed earlier in this series, possibly because neurotization for shoulder control and elbow flexion has become standard in the last few years. In 10 cases, one procedure was performed; in 6, two procedures; and in 2, three or more. Remarkably, in this series subscapular release was required in only four cases and it is notable that joint contractures rarely occur in obstetric palsy following breech delivery, especially in the presence of complete or partial avulsion.
For the assessment of postoperative results we used the Mallet scale,11 (fig. 4) an assessment of global movement of the extremity that looks at patterns of movement that may be either functional or maladaptive. This scale is practical for use in children aged 3 to 4 years, who can perform voluntary movements reliably on command, scoring shoulder functions as well as elbow flexion, but can also be applied in younger children by an experienced examiner. This scale is particularly useful for assessing results of obstetric brachial plexus palsy following breech delivery as in these cases total lesions rarely occur and upper lesions are predominant; in the present series this was 95% (n=61). We used the original five-point scale, score 1 representing no apparent function and score 5 normal function, although a three-point scale may be more practical, taking the original score 2 as score 1 and 4 as 3. In our experience, recovery of shoulder and other proximal muscle reinnervation is largely complete 2 years after nerve surgery. Thus, we report only cases that have a minimum follow-up of 2 years. Only in the case of secondary surgery will the functions possibly have changed at later follow-up.
The results of scoring according to the Mallet scale are shown in Table Table5.5. Because completely normal function (grade 5) was not scored in any instance, grade 4 was the maximum score. We may conclude that grade 4 scores were given in only slightly more than half the cases (58%). In the earlier cases, secondary procedures were performed more frequently; the Mallet scores of these are shown in Table Table6.6. The results of the cases in which only primary surgery was performed (Table 7) contrast favorably with the results for these cases.
Accessory nerves were used in 51 cases (80%); in 46 the nerve was connected to the suprascapular nerve. In these patients shoulder abduction of 30 to 90 degrees (Mallet 3) was found in 18 cases and abduction of more than 90 degrees (Mallet 4) in 25. Active external rotation of the shoulder 0 to 20 degrees (Mallet 3) was present in five of these cases and external rotation of more than 20 degrees (Mallet 4) in 32. This illustrates the effectiveness of accessory-suprascapular nerve transfer.
In this series, where upper lesions are predominant, the medial pectoral nerve, a branch of the lower trunk, was to be regarded as a good alternative for neurotizing the musculocutaneous nerve9; hence intercostals were rarely used. Good recovery of biceps developed in 19 of 22 cases of such neurotization. Biceps function also occurred in two patients in whom the hypoglossal nerve was used for neurotization.
Table Table88 shows the distribution of Mallet sum scores. When scores of 18 or more are regarded as a good result, as in 34 cases (53%), a fair result of between 14 and 18 was present in 13 cases (20%). When patients are not able to position their good hand in a good working position this must be regarded as a poor result, and generally this is the case when the score is less than 15, as found in 14 cases (21%). The inability to rotate the shoulder externally is a major component in this group.
Our finding of the predominance of an upper brachial plexus lesion with a great number of myelographic abnormalities following breech delivery can be regarded as typical of this group. This finding is confirmed by earlier reports.12
In this series, at primary surgery, we aimed at recovery of external rotation of the shoulder by neurotization of the suprascapular nerve in a large number of cases. The figures show that we were successful in a great number. Also, the rate of recovery of shoulder abduction was significant. There exists variability in the subjective appreciation of the functional result between the medical profession on the one hand and the parents and the patients on the other. The functional result is positively estimated with greater enthusiasm by patients and parents than the medical profession may conclude from the Mallet scale.
The need for intercostal nerve transfer is not as great in most cases as in the present series because of the successful use of the almost invariably well functioning medial pectoral nerves, although intercostals can provide a good alternative. In this series intercostal nerves were used only twice. Also, because of the great number of phrenic nerve palsy cases we refrained from the use of intercostals as in these cases intercostal nerve harvesting may increase the danger of respiratory difficulties.
The good results following accessory nerve transfer and pectoral nerve transfer support our attitude that this technique is a particularly useful method in cases of brachial plexus palsy following breech delivery. This is in agreement with an earlier report evaluating 119 cases of accessory nerve to suprascapular nerve transfer in obstetric birth palsy following both cephalic and breech presentation.13 Because of these good results we do not think it justified to use other often more complicated techniques to improve shoulder function in obstetric birth palsy following breech delivery.
In conclusion, we consider the application of restrictive nerve transfers in patients with an upper brachial plexus palsy following breech delivery important and effective in the presence of possible root avulsion. Thus, accessory to suprascapular nerve transfer and medial pectoral nerve to musculocutaneous nerve transfer are effective and useful for this kind of lesion.
Certainly, when ruptures and neuromas are present, intraplexal reconstruction with sural nerve transplants is the first choice. We no longer consider hypoglossal nerve transfer to be a good option; this will be the subject of a future publication. Malessy et al14 have also advised against this transfer; although reinnervation of target muscles is the result, functional results, especially in adults, are negligible.
We report the results of surgical treatment of 61 cases of upper brachial plexus lesions after vaginal breech delivery; three complete lesions were not included because of the small number, and in the latter cases the results of gain in hand function have until now been disappointing. In one child the follow-up period was just over 2 years, and distal results could not yet be evaluated as recovery of hand function can take many years to develop.
Obstetric brachial palsy following breech delivery is a typical group: upper lesions predominating with a great number of upper root avulsions and phrenic nerve lesions. For this group nerve transfers were suited: 51 accessory, 28 medial pectoral, 2 hypoglossal nerve transfers, and in 2 cases transfer of intercostals; in some cases the transfers were part of an extended brachial plexus reconstruction.
Generally, the results of both primary and possibly secondary operations in this series were rewarding: 53% good and 20% fair. In both these groups most patients are able to position and use their more or less normal hand such that they can function normally, without serious impairment according to the international classification. In the group that we classified as a poor result, the inability to rotate the shoulder externally is a major component; many children were still able to function fairly well by compensating, making the number of cases judged by parents to be satisfying even greater.