The Montefiore Einstein Approach to Brachial Plexus Birth Injury

Abstract

Introduction

Brachial plexus birth injury (BPBI) is a heterogeneous condition with variable recovery and potential for lifelong functional impairment.

Problem

Despite advances in care, substantial variability persists in evaluation, timing of intervention, and reconstructive strategy across institutions. Increasing evidence supports surveillance-based, multidisciplinary models that emphasize recovery trajectory, early identification of secondary deformity, and integration of surgical and rehabilitative care.

Solution

We describe the Montefiore Einstein approach to BPBI, a prospective, surveillance-driven, multidisciplinary care model spanning infancy through adolescence. This framework integrates serial clinical assessment, selective adjunctive diagnostics, structured nonoperative management, biologically informed microsurgical reconstruction, and surgeon-coordinated rehabilitation. Key components include early enrollment into a longitudinal surveillance pathway, standardized use of the Active Movement Scale, routine ultrasound screening for glenohumeral dysplasia, trajectory-based surgical decision-making, and combined proximal and distal nerve reconstruction strategies.

Conclusion

BPBI should be conceptualized as a longitudinal condition requiring surveillance-driven, multidisciplinary care. The Montefiore Einstein approach provides a reproducible framework that integrates serial clinical evaluation, biologically informed reconstruction, and coordinated rehabilitation to optimize functional outcomes across the lifespan.

Introduction

Brachial plexus birth injury (BPBI) is a heterogeneous condition with a highly variable natural history and the potential for substantial lifelong functional morbidity. Although many infants experience spontaneous neurologic recovery, up to 30% develop persistent weakness, contracture, joint deformity, or sensory deficits that compromise upper-limb function and quality of life.^1-6 Optimal outcomes depend on early recognition of recovery trajectory, timely intervention, and coordinated multidisciplinary care.

Despite decades of investigation, significant variability persists in the evaluation of BPBI, timing of intervention, and reconstructive strategy across institutions. Increasing evidence supports surveillance-based models that emphasize serial clinical examination, early identification of secondary deformity, biologically informed reconstruction, and surgeon–therapist coordination rather than rigid age-based algorithms.^7-11 These models conceptualize BPBI as a longitudinal disease process rather than a discrete diagnostic or surgical event.

The purpose of this manuscript is to describe the Montefiore Einstein approach to BPBI: a surveillance-driven, multidisciplinary, and collaborative surgeon–therapist–integrated model spanning infancy through adolescence that integrates diagnostic strategy, nonoperative management, microsurgical reconstruction, and structured rehabilitation.

Program Infrastructure & Multidisciplinary Surveillance

The Montefiore Einstein BPBI program is built on a proactive, longitudinal, multidisciplinary surveillance system that spans neonatal evaluation through early childhood and adolescence. Infants diagnosed at birth enter a coordinated pathway designed to foster continuity-of-care and minimize missed windows of opportunity for intervention or care fragmentation.^11,12

Neonates with shoulder dystocia and/or suspected BPBI are enrolled into a prospective surveillance pathway at birth and are automatically referred to our specialized clinic for initial evaluation following discharge. Patients with persistent injuries are followed prospectively through infancy, childhood, and adolescence. Care is coordinated by a multidisciplinary team consisting of pediatric hand and peripheral nerve surgeons, occupational and physical therapists with BPBI specialization, rehabilitation specialists, and ancillary providers. This group systematically tracks motor milestone trajectories, secondary sequelae such as glenohumeral dysplasia (GHD), and response to therapeutic interventions. This model draws on our previous work demonstrating the feasibility and benefits of early, longitudinal engagement.^3,8,11

Our surveillance system emphasizes early referral, facilitating early identification of neurologic plateau, evolving contracture, and joint dysplasia, enabling timely escalation of care. Families are engaged as partners through education and shared decision-making, promoting continuity and transparency across the lifespan. In these respects, our infrastructure parallels national protocols such as the Helsinki BPBI program, while emphasizing deeper integration of surveillance data into surgical planning and postoperative rehabilitation. ⁹

Infant Brachial Plexus Exam & Diagnostic Framework

The initial encounter begins with an open-ended caregiver storytelling. In our experience, this improves accuracy and establishes trust. While this process often elicits maternal guilt, it also provides a forum to acknowledge and address the guilt directly. If key elements are not volunteered, we ask specifically about maternal health issues (e.g., gestational diabetes, preeclampsia), induction of labor and instrumented delivery. Because many families do not understand the term “shoulder dystocia,” we ask whether the baby was “stuck” during delivery. We also inquire about cesarean delivery and the child’s hospital course. Concomitant central neurological issues including hypoxic-ischemic encephalopathy must be identified, as these conditions strongly influence prognosis for the child as a whole and necessitate early involvement of developmental pediatrics.^13,14

The foundation of the Montefiore approach is a structured, serial infant brachial plexus examination that emphasizes recovery trajectory rather than static, time-point assessment. BPBI recovery is a dynamic process that includes neuropraxic resolution, axonal regeneration, and motor reorganization. Early and repeated clinical examination by clinicians experienced in BPBI remains the most reliable determinant of prognosis and candidacy for intervention.

In this model, the physical examination—not imaging or neurodiagnostics alone—drives initial management decisions. Serial examination events are anchored on volitional motor milestones that reflect nerve physiology and maturation, including antigravity elbow flexion and shoulder external rotation, wrist and finger motion, and scapulothoracic mechanics. The Active Movement Scale (AMS) is the most appropriate metric for evaluation of infants and young children (despite its coarseness), and patients are scored by multidisciplinary consensus at clinic and therapy visits.^15-18 These outcomes correlate with long-term limb use; thus, children are conceptualized along a continuum of recovery rather than dichotomized as operative vs nonoperative.

Consistent with neuropraxic recovery, some children achieve AMS scores of 7 for all movements of the upper extremity within 8 weeks of birth; these patients’ injuries are considered transient. Finally, we assess biceps recovery at 3 months (with supinated elbow flexion and MRC testing). Supinated elbow flexion AMS ≥4 is strongly predictive of favorable outcome in upper-trunk predominant patterns. Failure of this recovery threshold by 3 months is a classic indication for escalation of care due to the persistence of shoulder dysfunction in this population.^19,20

Advanced imaging and electrodiagnostic studies are used selectively as adjuncts rather than screening tests. Magnetic Resonance Imaging (MRI) is limited by anesthesia requirements and imperfect correlation with functional outcomes and is therefore reserved for patients with suspected global injury.^10,21 MRI may be useful in distinguishing between preganglionic avulsions and extraforaminal ruptures, but commonly the examinations are insufficient to reveal meaningful structural details of the anterior and posterior rootlets and the spinal root lesions at the level of the foramen. Thus, until MRI sensitivity improves, we reserve it for global cases. ²² In global cases and four-root cases (“T1 hands”), MRI informs operative planning, particularly when contralateral C7 nerve root transfer is being considered. In older children, we have found that electrodiagnostic studies can be useful adjuncts in the evaluation of nerves that can be used as donors, such as the spinal accessory nerve, medial pectoral nerve, ulnar nerve, or intercostal nerves. Radiographs are obtained selectively when clavicle or humerus fracture is suspected.

Beginning at 6 weeks, we perform serial, point-of-care, screening ultrasound of the shoulder to evaluate the glenohumeral joint for posterior subluxation or changes in morphology of the humeral head: the sequelae known as glenohumeral dysplasia (GHD) (Figure 1). Patients may become dysplastic due to abnormal neural signal to surrounding musculature and the bone itself, resulting in unbalanced forces of contraction and compression about the joint.^1,4 Using the technique described by Grissom and Harcke, ultrasound enables visualization of the cartilaginous humeral head relative to the glenoid and allows a dynamic assessment in internal and external rotation. ²³ We measure the alpha angle, between the dorsal scapular line and a line tangent to the posterior humeral head (Figure 2). In our experience, ultrasound does not reliably characterize glenoid morphology after 12 months; at that point, MRI is obtained to guide decision-making. We also routinely evaluate diaphragm function with point-of-care ultrasound to assess phrenic nerve integrity, especially in cases where intercostal nerve transfers may be useful. Notably, in the presence of phrenic nerve palsy, while we rarely employ intercostal nerve transfer, when doing so, we will advocate for early tracheostomy.

Figure 1.

Example of point of care glenohumeral ultrasound to evaluate for glenohumeral dysplasia

Figure 2.

Example of alpha angle (yellow angle). Measured between the dorsal scapular line (green dotted line) and the tangent line (green dashed line) to the humeral head. The ossific nucleus is noted with a red arrow

Electrodiagnostic studies are used selectively, as early EMG has limited prognostic value in infants and does not outperform serial physical examination.^24-26 Routine electrodiagnostic studies are therefore unnecessary in most infants. Available evidence suggests that electrodiagnostic studies can be overly optimistic regarding recovery and may delay treatment; additionally, infants cannot reliably comply with the examination and frequently require sedation, further limiting applicability.

Nonoperative Management Pathway

Nonoperative management within the Montefiore model is active, structured, and time sensitive. We employ an extensive regional network of specialized pediatric hand therapists located on-site and in vetted satellite clinics. The brachial plexus surgeons and senior therapists, who specialize in BPBI, jointly select a therapy site for patients based on geographic convenience, schedule the initial appointment, and maintain continuous, closed-loop communication. Therapists follow a standardized protocol with real-time senior plexus therapist oversight to ensure consistent, coordinated management of all patients. This model has been demonstrated to be significantly superior to a decentralized model with less strict oversight. ⁸ All infants receive early therapy focused on range of motion, strengthening, sensory stimulation, and caregiver-directed home exercise. The goals are to preserve passive motion, stimulate volitional activation, prevent secondary deformity, and support cortical integration of emerging function in time with developmental milestones.

Glenohumeral dysplasia is abnormal and results in instability, ineffective shoulder movements and scapulothoracic compensation. As such, we are aggressive in our management. If GHD is identified, occupational therapy is prescribed and supination–external rotation (SupER) orthoses are utilized for 22 h per day to preserve glenohumeral joint alignment and mitigate progression (Figure 3).^27,28 Many patients improve with combined therapy and splinting, resulting in gradual discontinuation of the brace. ²⁸ Patients who do not improve with splinting and fail to neurologically recover are indicated for open reduction of their shoulder concurrent with plexus reconstruction, discussed below. In select cases, onabotulinum toxin type A injections may improve recovery by addressing antagonistic internal rotation dominance; these injections are typically combined with spica casting or an orthosis to maintain closed reduction.

Figure 3.

Example of a child in a supination-external rotation (SupER) orthosis, designed to preserve glenohumeral joint alignment and mitigate progression of glenohumeral dysplasia

Crucially, nonoperative care is not indefinite. Clinical data are reviewed continuously in biweekly multidisciplinary meetings to identify children unlikely to achieve meaningful spontaneous recovery, ensuring that therapeutic observation does not delay indicated reconstruction.

Indications & Timing for Microsurgical Reconstruction

Surgical intervention is pursued after failure of appropriate nonoperative treatment, guided by recovery trajectory and biologic potential. Timing of surgical decision-making remains among the most controversial aspects of BPBI care. For upper trunk–predominant injuries, available evidence supports a decision window less than 6 months, when spontaneous recovery can be reliably assessed and surgical benefit remains high.^6,10,29 Delayed surgery (>18 months) may diminish regenerative potential and contribute to secondary complications.

In contrast, children with global plexus or flail limbs have minimal likelihood of meaningful spontaneous recovery, and early exploration is strongly indicated.^6,29-31 Historical delays intended to improve anesthetic safety are increasingly obsolete; some authors now advocate nerve reconstruction as early as 8 weeks in global injuries, reflecting improvements in modern pediatric anesthesia and perioperative care.

Age alone does not preclude nerve reconstruction. Children presenting beyond traditional windows of 18 months remain candidates for nerve transfer when target muscles remain trophic and donor nerves are available. Growing evidence supports “late” nerve transfers, including spinal accessory nerve to infraspinatus motor branch transfer, to restore meaningful function even in older children and adolescents. ³²

The Montefiore Einstein protocol currently recommends surgical exploration in the following settings.

In C5-C6 palsy, infants present with loss of shoulder abduction and external rotation, elbow flexion, and forearm supination. If there is no biceps-mediated antigravity elbow flexion at 3 months, we proceed with surgery. Because functional elbow flexion requires an AMS score of 6 or greater, if scores plateau at ≤5 by 9 months, surgery is also indicated. Similarly, if shoulder function lacks antigravity function at 6 months, surgery is indicated.

There is also a nuanced population within the C5-C6 cohort. A sizable number of infants sustain Sunderland grade 1-2 C5 and/or C6 injuries, and most recover. ³³ Nevertheless, careful longitudinal examination is essential because partial recovery may be unrecognized. These infants may benefit from neurolysis and selective end-to-side transfers guided by intraoperative stimulation, including SAN-SSN end-to-side or MPN-AxN end-to-side, particularly because they remain at risk for GHD and require ongoing monitoring.^34-36 Therefore, we continue monitoring these infants for neurologic recovery. If this is not achieved by 1 year, surgery is indicated, as neurolysis can sometimes upgrade an infant from an AMS 6 to 7.

In C5-C6-C7 palsy, infants present similarly as above. C7 injury is difficult to ascertain. The child may or may not have deficits in radial nerve functions. However, presence of triceps function, wrist extension, and finger extension does not exclude a C7 injury, as C8 may innervate these movements (Figure 4). Importantly loss of C7 contribution may reduce elbow flexion strength through effects on brachioradialis function and the Steindler effect. In addition to the aforementioned surgical indications, failure of antigravity wrist extension or triceps function by 6 months is an indication for surgical intervention.

Figure 4.

A revised motor innervation of the brachial plexus representing the extent of C8 and T1 innervation

In C5-C8 preservation of T1 allows retention or recovery of finger and thumb flexion as well as weak wrist extension in some cases (Figure 4).^37,38 Alternatively, lack of elbow and finger extension confirms C8 injury. These children should undergo surgery at the earliest opportunity—often as early as 8 weeks and ideally before 12 weeks. True C5-T1 global palsies are uncommon, but when present they warrant the same early timing.

Finally, ultrasound-confirmed GHD that worsens despite Sup-ER orthosis treatment is an independent trigger to escalate to surgical care. In these cases, we perform an open reduction with coracoidectomy, subscapularis lengthening, and anterior capsulotomy. We do not perform a posterior axillary approach release, as it does not address subscapularis tightness or bony impingement from the coracoid.

Monthly reassessment by the multidisciplinary team is essential to identify indications for surgical intervention.

Surgical Strategy: The Montefiore Einstein Philosophy

Microsurgical reconstruction within the Montefiore approach is guided by four core principles: (1) prioritize restoration of major functional axes; (2) preserve and restore biologic pathways for supporting muscles and sensation; (3) exploit preserved donor nerve biology in BPBI; and (4) integrate surgery with surgeon-coordinated rehabilitation.

Although careful preoperative assessment and intraoperative exploration remain the most reliable foundations for planning, we incorporate intraoperative electrical nerve stimulation as a real-time adjunct to guide decision-making. Low-threshold stimulation correlates with favorable recovery and helps determine whether neurolysis alone is sufficient or whether nerve grafting and/or nerve transfer is required. ³⁶ Intraoperative findings frequently serve as the most crucial determinant of brachial plexus reconstruction strategy.

Our intraoperative algorithm proceeds as follows. Neurolysis is performed of all conducting neuromas. After neurolysis, nerve stimulation is performed at 0.5 mA using a handheld stimulator. If the corresponding muscle moves against gravity intraoperatively (consistent with MRC >2), no further surgery is recommended. If the muscle does not move against gravity, stimulation is repeated at 2 mA. Generally, we perform an end-to-side nerve transfer if antigravity movement is observed at this threshold (Figure 5). If there remains no antigravity movement at 2 mA, an end-to-end nerve transfer is performed in combination with neuroma excision and grafting. The medial antebrachial cutaneous nerve is a favored graft donor in many cases as the entire upper limb is already in the surgical field, making it easier to harvest than a more distant site such as the sural nerve in the lower limb (Figure 6). ³⁹ Peripheral nerve allograft is not utilized within our paradigm. Available evidence demonstrates variable outcomes, and concerns persist regarding regeneration distance and long-term durability in growing children.^40-42

Figure 5.

End-to-side nerve transfer of the spinal accessory to suprascapular nerve

Figure 6.

Cabled autografting in the brachial plexus utilizing multiple cables of medial antebrachial cutaneous nerves

In our practice, distal nerve transfers do not replace proximal reconstruction; rather, both are used when indicated. When viable rootlets exist, neuroma resection and autologous grafting are performed in concert with extraplexal transfers to increase axonal load, reinnervate supporting musculature, and preserve sensory pathways. Functional limb use depends not only on major movers but also on balanced stabilization, synergistic muscle activity, and protective sensation. Exclusive reliance on distal transfers risks neglecting these important contributors to outcome. Conversely, distal transfers provide reliable restoration of major functional axes—elbow flexion, shoulder external rotation, shoulder abduction and wrist extension—by shortening regeneration distance, leveraging healthy donor axons, and facilitating predictable cortical integration. Concomitant grafting supports minor muscles and sensory recovery. We consider sensory recovery to be of utmost importance. Restoration of protective sensation enhances safety, facilitates object manipulation, decreases neuropathic pain, and supports cortical reintegration.^10,43,44 When feasible, sensory pathways are reconstructed through grafting or, if necessary, targeted transfers performed alongside motor reconstruction.

We preferentially avoid repositioning the infant. Spinal accessory nerve to suprascapular nerve (SAN-SSN) transfer is performed through an extended anterior supraclavicular approach to permit distal decompression Figure 7).^45,46 Axillary nerve (AxN) reconstruction is performed to its anterior branch using either an anterior triceps-to-AxN nerve transfer or medial pectoral nerve (MPN)-to-AxN transfer (Figure 8).^47-49 In the absence of triceps function, alternative donors include ulnar fascicle, intercostal nerves, or thoracodorsal nerve.^50-52

Figure 7.

An anterior, supraclavicular spinal accessory to suprascapular nerve transfer performed through an extended anterior approach that permits distal decompression in infants

Figure 8.

An example of a medial pectoral nerve to axillary nerve transfers through an infraclavicular approach to the brachial plexus

For elbow flexion, we utilize the single fascicular (“Oberlin”) nerve transfer (Figure 9).^12,53-55 We prefer ulnar fascicular donor selection, but our decision is informed by the concept of the “median nerve hand.” In many C5-C8 patterns, median nerve–innervated muscles (e.g., flexor carpi radialis, flexor digitorum superficialis, anterior interosseous nerve–innervated muscles) remain functional because of preserved T1 contributions; these donors are therefore reliable for transfers such as fascicular elbow flexion reconstruction and anterior interosseous nerve (AIN)-to-extensor carpi radialis brevis (ECRB) nerve transfer for wrist extension (Figure 10).^38,56,57

Figure 9.

A single fascicular (“Oberlin”) nerve transfer utilizing a flexor carpi ulnaris (FCU) fascicle of the ulnar nerve to the musculocutaneous nerve branch to the biceps muscle

Figure 10.

An example of an anterior interosseous (AIN)-to-extensor carpai radialis brevis (ECRB) nerve transfer to reconstruct wrist extension

Scapular winging is often underappreciated; when serratus denervation is suspected, we consider transfer of T2 to the long thoracic nerve. Correction of scapulothoracic abnormal motion is a critical goal of both surgery to return neural signals from the plexus as well as occupational therapy directed at proper neural and biomechanic activation of the muscles that move the upper extremity.

Contralateral C7 transfer is reserved for select injuries with limited ipsilateral donor options and is individualized based on injury pattern, donor availability, and functional priorities. ⁵⁸ When employed, we use a prespinal approach and commonly direct contralateral C7 toward restoration of hand and wrist function via the median nerve, as we believe contralateral C7 is most reliable when directed to a single target (Figure 11).^59-61

Figure 11.

An intraoperative image of a transfers contralateral C7 nerve in the pre-spinal route in the prevertebral space, posterior to the esophagus and anterior to the longus colli. The longus colli protect the vertebral artery. The anterior division (AD) and the posterior division (PD) of the C7 nerve root have been labeled

Surgical Strategy: Specific Injury Patterns

In C5-C6 palsy, infants present with loss of shoulder abduction and external rotation, elbow flexion, and forearm supination. When operative treatment is indicated, we combine proximal neuroma excision and grafting (when viable) with distal transfers that restore major movers. C5 and C6 are grafted to the upper trunk. Distal transfers commonly include SAN-SSN, an anterior triceps-to-AxN transfer, and a single fascicular “Oberlin” nerve transfer. When elbow extension is weak, we use MPN-AxN rather than triceps-to-AxN.^12,49

In C5-C6-C7 palsy, infants present as previously discussed; severity is variable. Lower trunk function is preserved, so ulnar and median-innervated muscles typically remain reasonably strong and recover. Variation in innervation is common; in some cases, triceps is affected and requires ICN-to-triceps transfer. Wrist extension is often preserved by C8, but if it fails to recover, we perform AIN-ECRB transfer. ⁵⁷ Accordingly, we triage based on examination and intraoperative findings and use a combined strategy of distal transfers (SAN-SSN, MPN-AxN, Oberlin, ICN-Triceps, AIN-ECRB) and grafting of all viable roots. When C7 injury is severe enough to compromise long thoracic nerve function, we add T2-to-long thoracic nerve transfer.

In C5-C8 patterns (“T1/median hands”), lack of elbow and finger extension confirms C8 injury, but preserved T1 allows recovery of finger and thumb flexion, producing a “median hand” phenotype. ⁵⁷ These children require MRI to assess the number of root avulsions. We continue the combined transfer-and-grafting paradigm with increased use of extraplexal transfers, typically including SAN-SSN, ICN-Triceps, ICN-Musculocutaneous nerve (MCN), and AIN-ECRB, and we often add T2-to-long thoracic transfer to support scapular mechanics as noted. Grafting is performed from non-avulsed roots.

We generally address avulsions differently with increasing severity. When there is one avulsion (often C7), we graft C8 anatomically to the lower trunk, graft C5 to the posterior division of the upper trunk, transfer SAN-SSN, graft C6 to C7, and transfer ICN-MCN (Figure 12). With two avulsions (C7 and C8), the strategy is similar, but C6 is directed to C8 and C7 is left alone. With three avulsions, we believe that the next best available root is the contralateral C7.^60,61 In that setting, C5 is grafted to the posterior division of the upper trunk, the contralateral C7 is grafted to the middle trunk, and we perform SAN-SSN, and ICN-MCN transfers. In four-root avulsions with one remaining root (often C5), that root is grafted to the upper trunk divisions, contralateral C7 is transferred to the median nerve for hand reconstruction (as evidence demonstrates that contralateral C7 does best with single targets), and extraplexal SAN-SSN and ICN-MCN are performed. ⁵⁹ Multiple secondary reconstructions are anticipated.

Figure 12.

Intraoperative image of transfer of three intercoastal nerves to the musculocutaneous nerve

True C5-T1 global palsies are uncommon. When a five-root avulsion occurs without viable roots for grafting, we rely on extraplexal reconstruction: SAN-SSN, contralateral C7 to the median nerve, and ICN-MCN. In this setting, SSN supports shoulder abduction in addition to external rotation while the contralateral C7 is used to restore extrinsic hand function. We should underscore that the limited abduction obtained from SSN is acceptable, as external rotation is a much more important motion for functional independence. Additionally, we often graft C4 to C6-8 for sensory reconstruction, and we counsel families that multiple secondary reconstructions will be necessary.

Synkinesis may occur following nerve transfers. However, children demonstrate greater cortical plasticity and capacity for independent motor control than adults, an advantage that supports the use of nerve transfers and reinforces the importance of donor-activation–focused rehabilitation. ¹²

This framework provides structure without rigidity. Final reconstructive plans are refined intraoperatively based on stimulation findings, tissue quality, and donor availability. Creativity and biological reasoning remain central.

Postoperative Therapy & Rehabilitation

Postoperative rehabilitation is viewed as an extension of the reconstructive strategy rather than an adjunct. Therapy protocols are developed collaboratively by surgeons and specialized pediatric hand therapists to ensure that rehabilitation goals align directly with the operative plan and anticipated patterns of reinnervation. Postoperative and nonoperative rehabilitation strategies emphasize surgeon–therapist co-design, with protocols such as the Donor Activation Focused Rehabilitation Approach (DAFRA) and selective use of constraint-induced movement therapy (CIMT) linking motor re-education directly to reconstructive intent (Figure 13).

Figure 13.

Demonstration of the use of contraint-induced movement therapy (CIMT) to facilitate motor re-eduation after nerve transfer reconstruction

Rehabilitation emphasizes donor activation, motor re-education, and cortical integration using play-based therapeutic intervention. Milestone-based protocols such as DAFRA are employed after nerve transfers to reinforce donor–recipient coupling and promote volitional control as reinnervation occurs. ¹² Progression is guided by serial examination and functional recovery rather than rigid timelines, allowing adaptation to individual neurologic trajectories. CIMT is incorporated to address developmental disregard and to enhance purposeful use of the affected limb once sufficient motor activation is present. ⁶² CIMT is used judiciously and paired with active motor training to avoid premature constraint that may frustrate early recovery.

Orthotic management is integrated throughout the postoperative course to support joint alignment, prevent secondary contracture, and protect developing reconstructions. SupER orthoses and positioning strategies are applied when indicated to mitigate GHD and shoulder imbalance. ²⁸ These devices are continued in the postoperative period after open reduction in the operating room. Importantly, orthoses are used to support recovery rather than to mask neurologic return. Therapeutic taping techniques are also used, particularly for scapular dyskinesia, as both facilitative and supportive adjuncts tailored to the individual intervention plan.

As aforementioned, close communication between surgeons and therapists in our multidisciplinary model supports early identification of delayed activation, maladaptive movement patterns, and evolving joint pathology, enabling timely modification of therapy, additional interventions, or surgical reconsideration when needed. ⁸

Management of Older Children & Adolescents: A Brief Commentary

The Montefiore Einstein approach recognizes BPBI as a lifelong condition, and care does not conclude after infancy or early childhood. Older children and adolescents may present with residual weakness, contracture, joint deformity, or functional limitations despite prior nonoperative or operative management. These patients require individualized evaluation that accounts for remaining muscle trophism, joint integrity, and functional goals.

Contrary to traditional paradigms that restrict nerve reconstruction to early infancy, growing evidence supports the use of late nerve transfers in select older children and adolescents. Muscles affected by BPBI may remain trophic despite prolonged dysfunction, allowing meaningful reinnervation when appropriate donor nerves are available. Late spinal accessory nerve transfers to the infraspinatus have demonstrated reliable restoration of active external rotation even several years after birth injury, challenging rigid age-based exclusions. ³² In older children, electrodiagnostic studies can provide valuable adjunctive information regarding muscle viability and donor nerve availability, as children in this age group can more reliably cooperate with testing. These studies may help identify candidates for late nerve transfer procedures.

As children mature, functional evaluation also evolves. Children older than 3 years can reliably follow commands, allowing the use of the Mallet scoring system to assess shoulder function. The original Mallet classification evaluated global shoulder performance through five functional tasks: global shoulder abduction, global shoulder external rotation, hand-to-neck activity, hand-to-spine motion, and hand-to-mouth capability. In our practice, we follow the previously published Philadelphia Shriners modification of the Mallet classification, which adds the hand-to-navel task. ⁶³ This modification addresses an important limitation of the original system. Hand-to-spine motion requires shoulder extension in addition to internal rotation and therefore may underestimate internal rotation capacity in children who lack shoulder extension. Many children with BPBI cannot reach their spine despite having adequate internal rotation, making the hand-to-spine maneuver an unreliable gauge of internal rotation in this population.

Contracture management is an important aspect of care in older children. Elbow flexion contractures are common in BPBI and are thought to arise from relative shortening of the biceps muscle compared with the growing humerus. Surgical lengthening of the biceps has been described but carries the risk of weakening an already compromised elbow flexor mechanism. ⁶⁴ For this reason, we preferentially manage elbow flexion contractures nonoperatively. Serial casting or orthotic management may be helpful in preventing progression of elbow flexion contracture. ⁶⁵ When orthoses are used to maintain elbow extension and stretch the biceps muscle, positioning the forearm in pronation improves the effectiveness of the stretch.

In adolescents, reconstructive strategies often include a combination of late nerve transfers, tendon transfers, osteotomies, and soft-tissue balancing procedures. ⁴ Surgical planning prioritizes restoration of functional arcs that improve activities of daily living, positioning of the hand in space, and participation in age-appropriate activities. Whenever feasible, biologic reconstruction is favored over purely mechanical solutions to preserve adaptive potential.

Tendon transfers play an important role in the management of persistent deficits. Limited literature supports tendon transfer procedures in children younger than 2 years, and most centers reserve these procedures for patients between 2 and 5 years of age. Transfer of the latissimus dorsi and teres major muscles is commonly performed during this period to restore active external rotation. In our practice, this transfer is performed through an axillary incision. Both tendons are released and transferred as a conjoint tendon to the greater tuberosity of the humerus. Fixation is achieved using permanent sutures placed in a transosseous fashion through the greater tuberosity, providing secure attachment of the transferred tendons. However, we have now adopted the more extensive soft-tissue balancing and tendon transfers of adolescents into the younger population and frequently perform them in concert with late nerve transfers. ⁴

Forearm deformity is another frequent late manifestation of BPBI. The most common pattern in patients with global injuries is a supination contracture of the forearm. Recovery of the upper trunk-innervated supinator muscles, including the biceps and supinator, combined with deficient recovery of the pronator muscles creates an imbalance that results in a sustained supinated posture of the forearm. Passively correctible deformities may be treated with biceps rerouting, which converts the biceps tendon from a supinator into a pronator. In contrast, fixed deformities are typically managed with a one-bone forearm procedure in which the distal radius is fused to the proximal ulna in a functional position of forearm rotation.

Restoration of wrist extension represents another reconstructive challenge in children with C5-C7 involvement. When nerve reconstruction such as AIN–ECRB transfer is not feasible or when recovery remains incomplete, tendon transfer may be indicated. The pronator teres, commonly used for wrist extension transfers, is often weakened in these patients and therefore unavailable as a donor. Our preferred donor is the flexor digitorum superficialis (FDS) to the ring and middle fingers, performed as a Boyes transfer typically around 5-6 years of age. The FDS tendons provide adequate strength and excursion, and finger flexion is synergistic with wrist extension. We utilize a modification of the technique taught by the Philadelphia Shriners group in person communication to minimize unwanted supination forces. In this modification, one FDS tendon is routed from volar to dorsal through the interosseous membrane, while the second tendon is routed around the radial border of the wrist. This configuration introduces a slight pronation force in addition to wrist extension. In contrast, the original Boyes technique described routing both tendons through the interosseous membrane, which may generate an unwanted supination force. In patients who already lack adequate pronation, this can exacerbate the tendency toward supination contracture.

For shoulder deformity, we generally avoid humeral derotational osteotomies when possible. Instead, we prioritize soft-tissue balancing procedures and shoulder reanimation strategies as noted above that restore active motion and improve joint mechanics, addressing the underlying muscular imbalance rather than simply repositioning the limb.

In rare circumstances in which neither nerve transfers nor tendon transfers are feasible and functional deficits remain substantial, free functional muscle transfer may be considered. In these settings, free gracilis muscle transfer may provide restoration of key functions such as elbow flexion or finger flexion when local donor options are exhausted.

Postoperative rehabilitation in older children mirrors the principles applied in infancy, with continued emphasis on motor re-education, donor activation, and functional integration. Adolescents often demonstrate strong motivation and cognitive engagement, which can be leveraged to facilitate relearning and optimize outcomes.

By maintaining longitudinal surveillance and remaining open to intervention beyond early childhood, the Montefiore model seeks to address unmet functional needs across the lifespan rather than accepting residual deficits as inevitable.

Discussion: How We do it

The Montefiore Einstein approach aligns with contemporary institutional protocols (Miami, Helsinki, Philadelphia Shriners) while emphasizing deeper integration of surveillance, complementary distal and proximal reconstruction, anterior-only strategies, and surgeon-directed rehabilitation.^9-11,63 Rather than proposing a single operative algorithm, our model emphasizes longitudinal clinical assessment, early identification of recovery trajectories, integration of nonoperative and operative strategies, and close alignment between surgeons and therapists across the lifespan.

Several high-quality protocols provide context. The Miami and Helsinki programs outline structured pathways for early referral, serial examination, and coordinated multidisciplinary care.^7,9 The Philadelphia Shriners group provides a comprehensive contemporary overview of history, examination, selective imaging, and electrodiagnostics. ⁶³ We replicate many of these core elements, particularly standardized infant examination, avoidance of routine infant MRI, judicious radiographs when fracture is suspected, and selective electrodiagnostic testing.

Where the Montefiore Einstein approach differs is in degree of integration and biologic emphasis. Prospective surveillance, rather than episodic referral, is foundational, enabling earlier recognition of plateaued recovery, evolving GHD, and functional imbalance. We also emphasize the complementary role of distal transfers and proximal reconstruction, the deliberate avoidance of infant repositioning through anterior strategies when feasible, and a surgeon-directed rehabilitation model that treats therapy as integral to reconstruction rather than downstream care. The principles described are reproducible and align with a growing body of evidence supporting surveillance-based, multidisciplinary BPBI care.

Conclusion

BPBI requires surveillance-driven, multidisciplinary, and biologically informed care. The Montefiore Einstein approach integrates serial clinical examination, structured nonoperative management, complementary nerve transfers and grafting, and multidisciplinary-coordinated rehabilitation to optimize functional recovery across the lifespan.