We reviewed a consecutive series of 33 infants who

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1 Function of the upper limb after surgery for obstetric brachial plexus palsy C. E. Dumont, V. Forin, H. Asfazadourian, C. Romana From Hôpital d Enfants Armand Trousseau, Paris, France We reviewed a consecutive series of 33 infants who underwent surgery for obstetric brachial plexus palsy at a mean age of 4.7 months. Of these, 13 with an upper palsy and 20 with a total palsy were treated by nerve reconstruction. Ten were treated by muscle transfer to the shoulder or elbow, and 16 by tendon transfer to the hand. The mean postoperative follow-up was 4 years 8 months. Ten of the 13 children (70%) with an upper palsy regained useful shoulder function and 11 (75%) useful elbow function. Of the 20 children with a total palsy, four (20%) regained useful shoulder function and seven (35%) useful elbow function. Most patients with a total palsy had satisfactory sensation of the hand, but only those with some preoperative hand movement regained satisfactory grasp. The ability to incorporate the palsied arm and hand into a co-ordinated movement pattern correlated with the sensation and prehension of the hand, but not with shoulder and elbow function. J Bone Joint Surg [Br] 2001;83-B: Received 24 May 2000; Accepted after revision 11 January 2001 When spontaneous recovery does not occur following obstetric brachial plexus palsy, the indications for surgery and the timing and type of repair are still controversial. We describe the follow-up of 33 patients undergoing surgical treatment using the criteria and techniques described by Gilbert and Tassin. 1 The results were analysed according to the nerve roots involved and the type of nerve repair which was performed. Special attention was paid to the evaluation of hand function. The combined scores used to assess C. E. Dumont, MD V. Forin, MD H. Asfazadourian, MD C. Romana, MD Service d Orthopédie et de Chirurgie Réparatrice de l Enfant, Hôpital d Enfants Armand Trousseau, 26 Avenue du Dr. Arnold-Netter, Paris Cedex 12, France. Correspondence should be sent to Dr C. E. Dumont at Balgrist, Forchstrasse 340, 8008 Zürich, Switzerland British Editorial Society of Bone and Joint Surgery X/01/ $2.00 function of the upper limb gave new insight into the further management of patients with a total palsy. Patients and Methods Between 1986 and 1993, we treated consecutively 36 patients with obstetric brachial plexus palsy by nerve reconstruction; their mean age was 4.7 months. The decision to operate was based on an assessment of the strength of the biceps and deltoid at the age of three to four months. Absence of contraction in biceps and deltoid was an indication for operation. Of the 36 children, 33 were available for clinical assessment at a mean follow-up of 4 years 8 months (2 years 6 months to 10 years). There were 17 boys and 16 girls with a mean birth weight of 4254 ± 528 g. There were no bilateral lesions. Repair. Metrizamide myelograms were obtained before surgery. Exploration of the brachial plexus was followed by direct electrical stimulation of the nerve roots using a standard nerve stimulator. The muscle contractions were evaluated, and the observed lesions were classified as avulsion, conducting or non-conducting neuroma-in-continuity, or rupture. 2 Neurolysis or resection and reconstruction of the lesions was then performed. Reconstruction involved excision of the lesion and replacement by nerve grafts connecting the residual root to the distal cord or peripheral nerve (intraplexal repair). Extraplexal nerve reconstructions used surrounding nerves as donors. Secondary surgery (muscle and tendon transfers, muscle release, osteotomy) was performed at least 18 months after the primary repair. Physiotherapy involving various forms of active and passive exercises was undertaken by all patients before and after operation. Assessment. Each child was evaluated before surgery by surgeons and occupational therapists. An occupational therapist and an occupational medicine physician, who were not aware of the patient s history, carried out the follow-up examination. The polio scale (0 to 3) was used to grade motor activity before operation and at follow-up. 1 The Toronto grading system 3 (Table I) was used to measure abduction of the shoulder, flexion of the elbow, and flexion/extension of the wrist, fingers and thumb at follow-up. The hand movement score was defined as the mean of the Toronto grade for flexion and extension of the wrist, finger and thumb THE JOURNAL OF BONE AND JOINT SURGERY

2 FUNCTION OF THE UPPER LIMB AFTER SURGERY FOR OBSTETRIC BRACHIAL PLEXUS PALSY 895 Table I. The Toronto grading system Observation Gravity eliminated No contraction 0 Contraction, no movement 1 Movement < 1/2 range 2 Movement > 1/2 range 3 Full movement 4 Against gravity Movement < 1/2 range 5 Movement > 1/2 range 6 Full movement 7 Muscle grade Useful function 5 of a joint was defined as a Toronto grade of 6 or 7. Shoulder function was also evaluated by the classification of Mallet 6 from II to IV (Table II). The sensation of the hand was determined by a score combining thermal discrimination, and recognition of smooth, rough, hard, soft, sharp and round objects. The maximum score for one hand was eight. The score of the paralysed hand was given as a percentage of the normal side with 100% indicating that the hands were equally sensitive. Prehension was scored in the same manner. The following grips were assessed: spherical, thenar grasp, palmar grasp, tridigit, distal key pinch, lateral key pinch, and ungual. Finally, a bimanual score was used to evaluate the incorporation of the palsied hand into bimanual activities of daily life independently of the ability to grasp. This score refers to movements learned early in childhood, such as catching a ball, moving the hands horizontally round each other, rolling both hands vertically like puppets, all of which reflect acquisition of co-ordination patterns for the upper limb. Each movement was graded 1 when the activity used both hands symmetrically, 0.5 when the hands were used asymmetrically, and 0 when the palsied hand was not spontaneously incorporated in the movement. The maximum score combining the three movements was 3. Statistical analysis. The results are expressed as the mean ±SD. The ratio of roots suitable for repair was calculated as the number of roots grafted or treated by neurolysis divided by the number of roots injured. Correlation coefficients among the measured parameters were evaluated using the Kruskal-Wallis ranking test or the Spearman ranking test. Results Overall. In the 33 children available for follow-up the plexus lesion was on the right in 21 and on the left in 12. Preoperative evaluation showed that 13 had sustained an upper palsy and 20 a total palsy. Tables III and IV give the intraoperative findings and surgery performed in both groups. Transfer of latissimus dorsi was the usual form of secondary surgery used to provide abduction and external rotation of the shoulder, except in one patient (case 4) in whom transfer of teres major was used. Bipolar transfer of latissimus dorsi was used to restore elbow flexion, except in two patients (cases 4 and 26) in whom transfer of pectoralis minor was used. At follow-up, the results of tests when the children were unco-operative were discarded and recorded in Tables III and IV as not determined. Complications occurred in two patients. One (case 25) had a superficial wound infection which was successfully treated by debridement. In the other (case 27), nonunion of the clavicle occurred after a transclavicular approach. A complete rupture of the proximal graft was found during surgery to repair the clavicle. No further nerve reconstruction has been undertaken. Upper palsy group (C5-C6 and C5-C6-C7 lesions). There were 13 patients in this group (Table III). The most common finding was a neuroma of the superior trunk with no muscle response to electrical stimulation of the nerve root. Both C5 and C6 roots were involved in all patients while C7 was also affected in five. Avulsion of a single root was seen in two and of all the injured roots in two. Intraplexal nerve repair was considered to be suitable in 65% of the roots. Four of the five patients with a C5-C7 lesion had weak extension of the wrist (grade < 2) before surgery. All gained useful extension either by neurolysis or nerve reconstruction. Five patients required secondary transfers to the shoulder or elbow. At follow-up, the Toronto grade for abduction of the shoulder showed useful function in ten (70%) and flexion of the elbow in 11 (75%) of the 13 patients. The sensation and movement of the hand and the prehension and bimanual score were almost normal at the last follow-up. Total palsy group. There were 20 patients in this group (Table IV). Avulsions of C5 or C6 were less common than in the other roots. Intraplexal repair was considered to be Table II. Functional assessment according to the classification of Mallet 6 Shoulder assessment II III IV Active shoulder abduction (degrees) to 90 > 90 Active shoulder external rotation (degrees) 0 20 > 20 (with shoulder in adduction) Hand to head Impossible Difficult Easy Hand to back Impossible S1 T12 Hand to mouth Trumpet sign* = + Trumpet sign = ± Trumpet sign = 0 * shoulder abduction to lower gravity against a weak biceps. VOL. 83-B, NO. 6, AUGUST 2001

3 896 C. E. DUMONT, V. FORIN, H. ASFAZADOURIAN, C. ROMANA Table III. Surgery and follow-up in the group with upper palsy. Nerve repairs are indicated as donor nerve-recipient nerve Final follow-up Surgery Shoulder Elbow Mallet 6 Hand movement Hand abduction flexion score score sensitivity Prehension Bimanual Case Nerve lesions* Nerve repair Secondary surgery (max = 7) (max = 7) (max = 4) (max = 7) score (%) score (%) score (%) 1 NIC of the ST C5 SSN, C5/C6 LC Muscle transfer to the shoulder 2 NIC of the ST C5 SSN, C6 LC ND NIC of the ST C5 SSN, C6 MCN RA of C6, NIC C6 SSN, C5 LC Subscapularis release, of the ST and muscle transfers to the shoulder and elbow 5 NIC of the ST C5 SSN, C5/C6 LC Muscle transfer to the shoulder 6 RA of C5 and C6 AN SSN, UN MCN NIC of the ST AN SSN, ST neurolysis 8 NIC of the ST C5 SSN, C5/C6 LC ND ND ND 9 RA of C5, C6 AN SSN, UN MCN Muscle transfer to and C7 the elbow 10 NIC of the ST, C5 SSN, RA of C7 C5/C6 LC,C5/C6 PC 11 NIC of the ST C5 SSN, C5/C6 LC, Muscle transfer to and MT MT neurolysis the shoulder 12 NIC of the ST AN SSN, C6 LC, and MT C6/C7 PC 13 RA of C6, NIC of AN SSN, C5 LC, ND ND ND the ST and MT MT neurolysis * NIC, neuroma-in-continuity; RA, root avulsion; ST, superior trunk; MT, middle trunk C5 to T1, cervical root; LC, lateral cord; SSN, suprascapular nerve; MCN, musculocutaneous nerve; AN, accessory nerve; UN, ulnar nerve; PC, posterior cord; MT, middle trunk one bundle of the UN is connected to the MCN to regain flexion of the elbow 31 not determined suitable in 49%. Ten patients required one or more secondary muscle transfers to regain movement of the shoulder, elbow or hand. Forearm muscles which had been initially weak with varying degrees of reinnervation were the only ones available for transfer to the wrist or hand. At followup, the Toronto grade for abduction of the shoulder showed useful function (grade 6 or 7) in four (20%) and similar flexion of the elbow in seven (35%) of the 20 patients. Two subgroups of patients were defined according to their preoperative hand function. Group A contained three patients in whom there had been some motor function before surgery, and group B patients with a totally palsied hand. Despite the lack of significant muscle gain after operation, all group-a patients showed a much improved mean hand movement and prehension score than those in group B, simply because there had been some preservation of hand function before operation. None of the patients in group B regained useful movement of the wrist, fingers or thumbs after primary or secondary surgery. Hand function was severely impaired because of lack of active extension of the wrist and thumb despite secondary transfers. Sensation of the hand was well preserved in both groups. The bimanual score for the total palsy group correlated with the mean hand motion score (p < 0.05), the sensitivity score (p < 0.05) and the prehension score (p < 0.05), but not with the Mallet classification or the Toronto grade for abduction of the shoulder and flexion of the elbow. The better the hand function, the better was the pattern of bimanual co-ordination. Discussion The characteristics of the patients were similar to those of previous studies of children suffering from brachial plexus palsy at birth. 2,3,7,8 The criteria of Gilbert and Tassin 1 were used to decide whether to advise surgery. Delayed recovery of muscle strength has a poor prognosis in birth palsy 3,9,10 and therefore our aim was to achieve primary repair as soon as possible after the examination carried out at three to four months of age. The surgical techniques used for the primary repair and secondary reconstruction of the paralysed upper limb have been previously described We used combined scores for the assessment of hand movement, sensation, prehension and bimanual function, because there are no agreed standard methods of evaluation of hands in children. Other methods were too specific or not reproducible and were unsatisfactory for a study of children of different ages and with varying degrees of disability Upper palsy patients (Fig. 1). Surgery to improve abduction and external rotation of the shoulder, flexion of the elbow, and extension of the wrist was performed when necessary. Our patients had a variety of nerve lesions, THE JOURNAL OF BONE AND JOINT SURGERY

4 FUNCTION OF THE UPPER LIMB AFTER SURGERY FOR OBSTETRIC BRACHIAL PLEXUS PALSY 897 Table IV. Surgery and follow-up in the group with total palsy. Nerve repairs are indicated as donor nerve-recipient nerve Final follow-up Hand Surgery Shoulder Elbow Mallet 6 movement Hand abduction flexion score score sensitivity Prehension Bimanual Case Nerve lesions* Nerve repair Secondary surgery (max = 7) (max = 7) (max = 4) (max = 7) score (%) score (%) score (%) Group A 14 NR of the ST, C7 LC, C5 and C6 Subscapularis release, and NIC of the MC, not used because of muscle transfer to RA of C8 extensive fibrosis the shoulder 15 NR of the ST, C5 SSN, C5/C6 LC, NIC of the MC, MT neurolysis RA of C8 16 NIC of C5/ST, AN MCN, C5/ST Tendon transfer to the wrist RA of C6 to C8 neurolysis Group B 17 NIC of C5/ST, AN SSN, C5 MCN, Tendon transfer to the wrist RA of C6 and C7, IT neurolysis NIC of the IT 18 NIC of C5/ST C5 SSN, C5 LC Subscapularis release, muscle transfer to the elbow, and tendon transfers to the wrist and thumb 19 NIC of C5/ST, C5 SSN, AN MCN IC MN ND NIC of C5/ST, C5 MCN, C5 LC IC MN, forearm osteotomy NR of the ST and AN MCN, C5 SSN, Tendon transfers to the wrist, MT, NIC of the IT C6/C7 PC, IT neurolysis fingers and thumb 22 NIC of C5/ST, AN SSN, C5 LC NR of the ST and AN SSN, IT neurolysis IC MCN, muscle transfer to MT, NIC of the IT the shoulder and tendon transfer to the wrist 24 NR of C5/ST, RA AN MCN, C5 SSN, Tendon transfer to the wrist of C6 to C8, T1/IT neurolysis NIC of T1/IT 25 NIC of the ST, AN SSN, C5 MC, ND RA of C7 to T1 C6 MN 26 RA of C5 to C8, AN SSN, T1/IT Muscle transfer to the elbow, NIC of T1/IT neurolysis and tendon transfers to the wrist, fingers and thumb 27 NIC of the ST, C5/C6 LC, C6 SSN, Surgery for clavicle nonunion, RA of C7 and C8, C8/IT neurolysis rupture of proximal nerve graft NIC of T1/IT 28 NIC of C5/ST, C5/ST neurolysis Subscapularis release, forearm RA of C6 and C7, AN MCN, IT neurolysis osteotomy, tendon transfer NIC of the IT to fingers 29 RA of C5 and C6, AN SSN, C7 LC NIC of the MT IT neurolysis and IT 30 NIC of the ST C5/C6 LC, C7 SSN and MT, RA of C8 and T1 31 NIC of the ST, C5 SSN, C6 LC, MT and IT MT/IT neurolysis 32 NIC of the ST, C5 SSN, C6 LC ND ND ND RA of C7 to T1 33 NIC of the ST, C5 SSN, C6 LC/PC, Muscle transfer to the elbow ND MT and IT C7/C8 PC/MC and tendon transfer to the thumb * NR, nerve rupture; ST, superior trunk; NIC, neuroma-in-continuity; MC, medial cord; RA, root avulsion; IT, inferior trunk; MT, middle trunk LC, lateral cord; SSN, suprascapular nerve; AN, accessory nerve; MCN, musculocutaneous nerve; PC, posterior cord; MN, median nerve not determined VOL. 83-B, NO. 6, AUGUST 2001

5 898 C. E. DUMONT, V. FORIN, H. ASFAZADOURIAN, C. ROMANA Fig. 1 Operative findings for the 13 children with an upper palsy. The corresponding case numbers are indicated for each pattern of nerve lesion. Neuromas are indicated by a black hairline and a foramen filled in black corresponds to an avulsed root. including non-conducting neuroma-in-continuity and root avulsions, requiring plexo-plexal nerve reconstructions, and occasionally extraplexal nerve reconstructions. Most regained useful function of the shoulder and elbow. Five of 13 (38%) benefited from secondary muscle transfer procedures. Their shoulder and elbow function was only slightly worse than that reported by Clarke et al 5 for neurolysis of a conducting neuroma-in-continuity, and comparable to that of other nerve reconstructions in Erb s palsy, even although the assessment criteria were very different. 22,23 None of these children developed significant impairment of co-ordination patterns in the upper limb. Total palsy patients (Fig. 2). Root avulsions were very common in patients with a total palsy. Extraplexal nerve reconstructions were therefore frequently required, and were the treatment of choice. The aim of nerve reconstruction was to provide useful shoulder and elbow function, as well as adequate sensation of the hand. Nerve connection to the deltoid was rarely performed because insufficient donor nerves were available. This may partly explain the inferior outcome in abduction of the shoulder in patients with a total palsy compared with those with an upper palsy. Also, despite similar rates of nerve reconstruction to the biceps, useful flexion of the elbow was regained much more frequently by patients with an upper palsy than by those with a total palsy. We therefore assume that the differences in shoulder and elbow function in the two groups are not only due to the number of roots injured and the feasibility of repair, but also to differences in the success rates of nerve repair in both groups as observed by Laurent and Lee. 9 Neurolysis of the lower roots did not greatly improve muscle strengths of the wrist or hand in our patients with a total palsy, as has been reported by Clarke et al. 5 Some irreparable lesions such as intraforaminal avulsions, partial avulsions, and mixed injuries, 24 were probably treated by reconstruction or neurolysis because the real extent of the nerve lesion had been underestimated before and during surgery. Preoperative CT combined with myelography and the measurement of intraoperative evoked potentials would undoubtedly improve the diagnosis of these lesions, although none of these methods is completely reliable for detecting root avulsion or mixed injuries. 25 All forms of surgery were comparable in providing sensation to the hand. No reconstruction of the superior trunk, lateral cord, or median nerve was better at providing prehension. Most children lacked active extension of the THE JOURNAL OF BONE AND JOINT SURGERY

6 FUNCTION OF THE UPPER LIMB AFTER SURGERY FOR OBSTETRIC BRACHIAL PLEXUS PALSY 899 Fig. 2 Operative findings for the 20 children with a total palsy. The corresponding case numbers are indicated for each pattern of nerve lesion. Neuromas are indicated by a black hairline and a foramen filled in black corresponds to an avulsed root. Three patients had no neuroma or avulsion of T1 and all had partial muscle function in the hand before surgery. wrist and thumb, resulting in impaired grasp, particularly when extrinsic flexion was active. Unfortunately, tendon transfers to restore extension of the wrist, finger or thumb failed, probably because the muscles transferred were only partly reinnervated. There was a strong correlation between hand movement, sensation and prehension, and the incorporation of the palsied hand into bimanual activities. This indicates that reasonable hand function is required to incorporate the palsied hand into bimanual activities. Hand sensation is especially crucial, because insensitivity from birth may result in the limb being ignored, and selfmutilation may occur. Satisfactory shoulder and elbow function alone did not lead to the incorporation of the limb into bimanual activities when there was insufficient sensation in the hand, as reported by Masse. 26 By contrast, our patients with upper palsy developed almost normal coordination patterns, although some experienced impairment of shoulder or elbow function. This underlines the importance of the hand in the development of patterns of coordination in infants and toddlers Psychological disorders resulting from impaired patterns of co-ordination and perception of body scale may partly explain the high level of behavioural problems recently observed in children with obstetric brachial plexus palsy. 4 Restoration of hand function is therefore important and must form part of the surgical strategy in children with a total palsy. Elective nerve connections to the shoulder and elbow of patients with a total palsy have been abandoned in our practice. Neurolysis of the lower root is only considered in cases in which the preoperative muscle power in the hand is grade two or more, suggesting that T1 is intact. In other patients, we now favour nerve reconstruction to the medial and posterior cord. This strategy requires accurate preoperative evaluation of the shoulder muscles, especially latissimus dorsi and pectoralis minor, because they can, when sufficiently strong, be used for transfer to the shoulder and elbow, thus avoiding nerve reconstructions to these sites. 30 VOL. 83-B, NO. 6, AUGUST 2001

7 900 C. E. DUMONT, V. FORIN, H. ASFAZADOURIAN, C. ROMANA We thank Sophie Chabran and Jean-Pierre Salasc for their contribution to the functional evaluation of the children. No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. References 1. Gilbert A, Tassin J. Réparation chirurgicale du plexus brachial dans la paralysie obstétricale. Chirurgie 1984;100: Terzis J, Liberson W, Levine R. Obstetric brachial plexus palsy. Hand Clinics 1986;2: Michelow B, Clarke HM, Curtis CG, et al. The natural history of obstetrical brachial plexus palsy. Plast Reconstr Surg 1994;93: Bellew M, Kay SPJ, Webb F, Ward A. Developmental and behavioural outcome in obstetric brachial plexus palsy. J Hand Surg [Br] 2000;25-B: Clarke HM, Al-Qattan MM, Curtis CG, Zuker RM. Obstetrical brachial plexus palsy: results following neurolysis of conducting neuromas-in-continuity. Plast Reconstr Surg 1996;97: Mallet J. Paralysie obstétricale du plexus brachial: traitement des séquelles: primauté du traitement de l épaule: méthode d expression des résultats. Rev Chir Orthop 1972;58(Suppl 1): Slooff A. Obstetric brachial plexus lesions and their neurological treatment. Clin Neurol Neurosurg 1993;95: Terzis JK, Papakonstantinou KC. Management of obstetric brachial plexus palsy. Hand Clin 1999;15: Laurent JP, Lee RT. Birth-related upper brachial plexus injuries in infants: operative and nonoperative approaches. J Child Neurol 1994;9: Waters PM. Comparison of the natural history, the outcome of microsurgical repair, and the outcome of operative reconstruction in brachial plexus birth palsy. J Bone Joint Surg [Am] 1999;81-A: Hentz VR. Microneural reconstruction of the brachial plexus. In: Green D, ed. Operative hand surgery. Vol. 2, New York: Churchill Livingstone, 1993: Zancolli EA, Zancolli ER Jr. Palliative surgical procedures in sequelae of obstetrical palsy. In: Tubina R, ed. The Hand. Vol. 4, Philadelphia: Saunders, 1993: Doi K. Obstetric and traumatic pediatric palsy. In: Peimer A, ed. Surgery of the hand and upper extremity. Vol. 2, New York: McGraw- Hill, 1995: Kopp CB. Fine motor abilities of infants. Dev Med Child Neurol 1974;16: Cope EB, Antony JH. Normal values for the two-point discrimination test. Pediatr Neurol 1992;8: Thibault A, Forget R, Lambert J. Evaluation of cutaneous and proprioceptive sensation in children: a reliability study. Dev Med Child Neurol 1994;36: Yekutiel M, Jariwala M, Stretch P. Sensory deficit in the hands of children with cerebral palsy: a new look at assessment and prevalence. Dev Med Child Neurol 1994;36: Beckung E, Uvebrant P. Motor and sensory impairments in children with intractable epilepsy. Epilepsia 1993;34: Van Heest A, House J, Putnam M. Sensibility deficiencies in the hands of children with spastic hemiplegia. J Hand Surg [Am] 1993;18-A: Largo RH, Howard JA. Developmental progression in play behaviour of children between nine and thirty months. I: Spontaneous play and imitation. Dev Med Child Neurol 1979;21: Sundholm LK, Eliasson AC, Forssberg H. Obstetric brachial plexus injuries: assessment and functional outcome at age 5 years. Dev Med Child Neurol 1998;40: Gilbert A, Brockman R, Carlioz H. Surgical treatment of brachial plexus palsy. Clin Orthop 1991;264: Laurent JP, Lee R, Shenaq S, et al. Neurosurgical correction of upper brachial plexus birth injuries. J Neurosurg 1993;79: Mackinnon S. Surgical management of the peripheral nerve gap. Clin Plast Surg 1989;16: Hashimoto T, Mitomo M, Hirabuki N, et al. Nerve root avulsion of birth palsy: comparison of myelography with CT-myelography and somatosensory evoked potential. Radiology 1991;178: Masse P. Obstetrical paralysis of the brachial plexus. II Therapeutics: treatment sequelae surgical possibilities for the elbow and the hand. Rev Chir Orthop Reparatrice Appar Mot 1972;58(Suppl 1): Konczak J, Borutta M, Topka H, Dichgans J. The development of goal-directed reaching in infants: hand trajectory formation and joint torque control. Exp Brain Res 1995;106: Newell KM, McDonald PV, Baillargeon R. Body scale and infant grip configurations. Dev Psychobiol 1993;26: Touwen BC. The neurological development of prehension: a developmental neurologist s view. Int J Psychophysiol 1995;19: Suenaga N, Minami A, Kaneda K. Long-term results of multiple muscle transfer to reconstruct shoulder function in patients with birth palsy: eleven-year follow-up. J Pediatr orthop 1999;19: Oberlin C, Béal D, Leechavengongs S, et al. Nerve transfer to biceps muscle using a part of ulnar nerve for C5-C6 avulsion of the brachial plexus: anatomical study and report of four cases. J Hand Surg [Am] 1994;19-A: THE JOURNAL OF BONE AND JOINT SURGERY